SOP Coal Loss Accounting Qualitative (Part II)

CTC VISION & MISSIONCTC ACTS AS A CATALYST, BY PROVIDING GROUP WIDE

TECHNOLOGICAL SERVICES IN SUPPORT OF UNIT’SEFFORTS FOR :

• TECHNICAL PROBLEM SOLVING• COST REDUCTION

• SHARING KNOWLEDGE AND EXPERIENCE

MSD VISION & MISSIONVISION

TO BE THE PREFERRED SOLUTIONPROVIDER FOR ACHIEVING COMMERCIAL

EXCELLENCE ACROSS THEADITYA BIRLA GROUP

MISSION

CREATE VALUE BY INSTITUTIONALISINGSYSTEMS, INTRODUCING BEST PRACTICES

AND REALISING GROUP SYNERGY

SOP Coal Loss Accounting : Qualitative (Part-II) has been developed on the foundation of following group values –

INTEGRITY

We define Integrity as honesty in every action. Each one of the Coal Management team should act and take decisionsin a manner that are fair, honest and following the highest standards of professionalism. ‘Integrity’ should be thecornerstone for all the dealings, be it with customers, employees, suppliers, partners, shareholders, the communities orthe government.

COMMITMENT

On the foundation of Integrity, Commitment should be seen as “Doing whatever it takes to deliver as promised”. Eachone of the Coal Management team should take ownership for their work, teams and the part of the organization theyare responsible for. Through this value they shall build an even sharper results oriented culture that is high on reliabilityand accountability. Their commitment is likely to make them a formidable leader and competitor in every market thatthey are in.

PASSION

Passion is defined as a missionary zeal arising out of an emotional engagement with work, which inspires each one togive his or her best. Each one of the Coal Management team are expected to be energetic and enthusiastic in the pursuitof their goals and objectives. They should recruit and actively encourage employees with a ‘Fire in the belly’. With thisValue, they would build a culture of innovation and break-through thinking leading to superior customer satisfactionand Value creation.

SEAMLESSNESS

Seamlessness is understood as thinking and working together across functional silos, hierarchy levels, across businesslines and geographies. Each one of the Coal Management team shall demonstrate high level of teamwork throughsharing and collaborative efforts and garner the synergy benefits from working together. Before they can truly benefitfrom a borderless world, they need to build a borderless organization. They should visualize free flow of knowledgeand information across the Group.

SPEED

Speed is looked upon as responding to internal and external customers with a sense of urgency. They should continuouslyseek to crash timelines and ensure expeditious completion of their tasks. Each one of the Coal Management teamshould aim on time service to the present and future needs of their customers.

GROUP VALUES

l Integrity l Commitment l Passion l Seamlessness l Speed

ACKNOWLEDGEMENTS

We would like to give special thanks to our group members, who have given their continued

support and proactive suggestions/ discussions which has gone a long way in making and

finalizing this SOP.

We would like to put on record our deep appreciation for the valuableinputs received during visit to the following units:

l Shri NK Sharma – Renusagar Power Division

l Shri R K Gupta – Renusagar Power Division

l Shri V N Srivastava – Awarpur Cement Works

l Shri Dinesh Randad – Awarpur Cement Works

l Shri R S Lawrence – Awarpur Cement Works

l Shri Sunil Kothari – Rajashree Cement

l N K Dwivedi – Rajashree Cement

l Shri B N Agarwal – Harihar Polyfirbres

l Shri Rajendra Jain – SFD Nagda

l Shri SK Dhanuka - SFD Nagda

l Hindalco – Renusagar Power Division

l Awarpur Cement Works

l Rajashree Cement

l SFD Nagda

STANDARD OPERATING PROCEDUREON

COAL LOSS ACCOUNTINGQUALITATIVE

(Part II)

MANAGEMENT SERVICES DIVISION&

CENTRAL TECHNICAL CENTREMarch 2007

SOP-Coal Loss Accounting : Qualitative, (Part-II)

Management Services Division & Central Technical Centre 1

TABLE OF CONTENTS

1. Coal Quality Overview ....................................................................................................................... 3

1.1 Grades of Coal ................................................................................................................ 5

1.2 Coal Contents ................................................................................................................. 6

1.3 Coal Quality Control Parameters ................................................................................... 7

1.4 Proximate Analysis ........................................................................................................ 8

1.5 Ultimate Analysis ........................................................................................................... 10

1.6 Grindabilty ..................................................................................................................... 12

1.7 Use of Coal in Power Generation .................................................................................. 12

1.8 Use of Coal in Cement Industries ................................................................................. 13

1.9 Effect of Coal Quality on Power Plant Performance .................................................... 13

1.9.1 Common problems due to poor and inconsistent quality of coal ................................... 13

1.9.2 Benefits of washed coals ................................................................................................ 14

1.0 A Coal quality analysis flow diagram .......................................................................................... 15

1.0 B Testing standards for coal and coke ......................................................................................... 15

1.0 C Coal sampling flow diagram – Hindalco, Renusagar ............................................................... 16

1.0 D Coal sampling flow diagram – Grasim, Rajashree Cement ...................................................... 17

1.0 E Coal sampling flow diagram – Awarpur Cement Works ........................................................... 18

2. Coal Sampling .................................................................................................................................... 19

2.1 General Principles of Sampling .................................................................................................... 19

2.2 General Procedures for Establishing a Sampling Scheme ............................................................ 20

2.3 Design of Sampling Scheme .......................................................................................................... 21

2.4 Joint Sampling ............................................................................................................................... 21

2.5 Auto Sampling .............................................................................................................................. 22

2.6 Dust Suppression System ............................................................................................................. 23

3. Procedure for Determination of Moisture ............................................................................................ 24

4. Procedure for Determination of Fixed Carbon Percentage in Coal ..................................................... 25

5. Procedure for Determination of Volatile Matter in Coal ..................................................................... 26

6. Procedure for Determination of Ash Content in Coal .......................................................................... 28

7. Procedure for Determination of Calorific Value .................................................................................. 30

SOP-COAL LOSS ACCOUNTING : QUALITATIVE, (PART-II)


Management Services Division & Central Technical Centre2

8. Procedure for Determination Hardgrove Grindabilty Index of Coal ................................................... 36

9. Procedure for Sampling and Fineness Test of Pulverized Coal .......................................................... 38

10. Procedure of Sampling Coal from Trucks During Unloading ............................................................. 45

11. Procedure for Collection, Preparation and Analysis of Samples from Railway Wagons OutsidePlant ..................................................................................................................................................... 47

12. Coal Quality Testing Equipments ....................................................................................................... 52

13. Procedure for Determination of Boiler Efficiency .............................................................................. 60

14. Glossary -Coal ..................................................................................................................................... 68

Annexure -1 Technological Development in Coal Testing equipments ............................................... 73

Annexure – 2: Daily Coal Quality Reporting Format ......................................................................... 87

Annexure – 3 : Monthly Coal Analysis Report ................................................................................... 88

1. Overview of Coal Mining ................................................................................................................ 89

2. Handling of Coal at Mines .............................................................................................................. 91

3. Loading of Coal on Truck or Rake At Mines .............................................................................. 96

4. Loading or Discharge of Coal from Vessel ................................................................................... 102

5. Transit of Coal .................................................................................................................................. 108

6. Stock Verification .............................................................................................................................. 110

Annexure – 1: Risk Assessment Procedure .................................................................................. 113

TABLE OF CONTENTS

SOP-COAL LOSS ACCOUNTING : QUANTITATIVEMINE TO FACTORY



1. COAL QUALITY - OVERVIEW

Coal becomes greater in value and rank as it ages and therefore loses its undesirable components as

time passes. The amount of carbon increases from about 65 percent to 96 percent with time, between

the stages of Peat to Lignite as shown in fig.1 Hydrogen decreases from five percent to two percent.

Oxygen can decrease from amounts of up to 30 percent to traces as low as one percent. Sulphur’s

component changes from a low trace to as much as four percent in the sub-bituminous and bituminous

stages back to small traces again. Moisture decreases as well through the stages of formation from 70

percent to five percent.

Fig.1 VARIOUS STAGES OF COAL FORMATION

Coal quality is evaluated by composition of carbon, moisture, volatile matter and ash etc. This

composition ultimately determine the value of coal.

• Moisture is a component that costs money to transport as well as it consumes energy. It is

therefore seen as a negative quality. Moisture should be as minimum as possible.

• Ash is viewed negatively as it is the product of inflammable materials. It not only lowers

the quality of coal but also increase the transportation and handling cost.

• Carbon is main component of coal .It acts as a main heat generator during burning. It

should be as maximum as possible.



• Volatile matter is the component that will generate the heat when coal is burnt and therefore is

the positive component. High volatile matter content indicates easy ignition of fuel.

Based on fixed carbon and moisture contents, coal can be broadly classified into two catagories as

shown in Fig. 2

A Typical Proximate analysis of various coals is shown in graph.

c o n t e n t s

T y p i c a l proximate a n a l y s i s o f v a r i o u s c o a l s ( I n p e r c e n t a g e )

6 0

5 0

4 0

3 0

2 0

1 0

0M o i s t u r e A s h V o l a t i l e m a t t e r F i x e d c a r b o n

P e

r c

e n

t a

g e

69.4 8.5

38.6

1417

20.7

29.8

23.3

34.7

46.851.3

I n d i a n C o a l

Indonesian Coal

South African Coal

Fig. 2



Elements which are found in coal include carbon, hydrogen, sulphur, nitrogen, and oxygen.

1.1 Grades of Coal

The common coal used in Indian industry is bituminous and sub-bituminous coal. The gradation

of Indian coal is based on its calorific value.

The quality of coal is specified by notified agencies by useful heat value (UHV) is as follows:

Normally D, E and F coal grades are available to Power Sector.

The formula for calculation of UHV is as follows

UHV = 8900 - 138(A + M) kcal/kg

Where

UHV = Useful heat value

A = % Ash

M = % Moisture in coal determined under standard conditions of 60% RH & 40°C basis

Grade Calorific Value range- (KCal / Kg)

A Exceeding 6200

B Exceeding 5600 but not exceeding 6200

C Exceeding 4940 but not exceeding 5600

D Exceeding 4200 but not exceeding 4940

E Exceeding 3360 but not exceeding 4200

F Exceeding 2400 but not exceeding 3360

G Exceeding 1300 but not exceeding 2400



1.2 Coal Contents :

The typical raw coal components, presently being used by the power stations is given below:

1. Ash Content: 30% to 55%, generally around 45%.

2. Moisture content: 4% to 21% except in rainy season when it goes higher in some cases.

3. Sulphur content: 0.2% to 1.0%

4. Gross Calorific Value: 3000 K Cal/kg. to 5000 K Cal/kg. (3500 K Cal/kg.)

5. Volatile matter: 18% to 25 %

6. Fixed Carbon 20% to 38%

Elemental analysis, moisture content, and grades of typical Indian coals

Coal C% H % S% N2% O2% Ash% Moisture GCV UHVGrade % (Kcal/Kg) (cal/gm)

D 30-33 2.1-2.4 0.4-.6 0.7-.8 NA 25-27 7-8 4999-5555 4332-4760

E 37.9 2.4 0.53 0.8 6% 30.4 7.5 4529.0 3670.0

F1 41.87 3.33 0.56 0.94 6% 34.07 7.8 4137.0 3122.0

F2 44.47 3.37 0.35 0.99 6% 36.3 8.4 3833.0 2731.0

Sulphur

Moisture

VolatileMatter

Ash

Fixed carbon

0 20 40 60 80 100

Minimum Maximum

0.2

1.0

4 2130 55

18 2520 38



1.3 Coal quality control parameters :

The quality of coal is primarily measured by how well it burns, how much heat it gives out in

the process, and how much ash it leaves behind afterwards. These characteristics depend on

how much of the coal is fuel (i.e. carbon and hydrogen) and how much of it is non-combustible

components like water and mineral impurities. As a first step following components are analyzed

by measuring the change in weight of a sample heated and ultimately burnt to yield.

Moisture : The water given off by heating to 105ºC in nitrogen (to prevent any

burning).

Volatile Matter : Gases and vapours formed by decomposition of the coal by heating in

nitrogen to 900ºC. These gases contain virtually all of the coal’s hydrogen

and the carbon which combines with it (e.g. as methane, CH4).

Fixed carbon : Fixed carbon is the carbon left over after the volatiles have been driven

off, determined from the change in weight when the devolatised sample

is burnt in air.

Ash : Ash is the incombustible residue; mostly from mineral impurities in the

coal. The ash content is the most important measure of coal quality.

Calorific Value : The Calorific Value (energy content) of the coal is measured by burning

a small sample in a calorimeter. The energy released is usually measured

in mega joules per kilogram (MJ/kg), or giga joules per tone (GJ/t), which

are the same. The fuel energy of any coal is about 32 MJ/kg; this is reduced

according to the content of water and mineral impurities. The Calorific

Value is the most important measure of coal value.

Calorific Value is a complex function of the elemental composition of the coal. Calorific

value is mostly determined by experimental measurements.

A close estimate can be made with the Dulong formula

GCV = (144.4 * %[C]) + (610.2 * % [H])-(65.9 * % [O]) +(0.39 * %[O]2)

Where C = Carbon, H = Hydrogen O = Oxygen

Calorific value (CV) is given in Kcal/kg or Btu/lb. Values of the elements C, H, and O, are

calculated on a dry ash-free coal



1.4 Proximate analysis

Proximate analysis is the simpler of the tests and is used to determine the moisture, ash,

volatile matter and fixed carbon content.

Determines (on an as-received basis)

Fixed carbon (solid fuel left after the

volatile matter is driven off).

Moisture content

Volatile matter (gases released when

coal is heated).

Ash (impurities consisting of silica, iron,

alumina and other incombustible matter)

Significance of various parameters in proximate analysis

a. Fixed carbon

Fixed carbon is the solid fuel left in the furnace after volatile matter is distilled off. It consists

mostly of carbon but also contains some hydrogen, oxygen, sulphur and nitrogen not driven

off with the gases. Fixed carbon gives a rough estimate of heat value of coal.

b. Volatile Matter

Volatile matters are the methane, hydrocarbons, hydrogen and carbon monoxide, and

incombustible gases like carbon dioxide and nitrogen found in coal. Thus the volatile matter

is an index of the gaseous fuel present. Typical range of volatile matter is 20 to 35%

Volatile matter

Proportionately increases flame length and helps in easier ignition of coal

Sets minimum limit on the furnace height and volume.

Influences secondary air requirement and distribution aspects.

Influences secondary oil support

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c. Ash content

Ash is an impurity that will not burn. Typical range is 15 to 40%

Ash

Reduces handling and burning capacity

Increases handling cost

Affects combustion efficiency and boiler efficiency

Causes clinkering and slagging

d. Moisture content

Moisture in coal decreases the heat content per kg of coal. Typical range is 6 to 14%.

Moisture

Increases heat loss, due to evaporation and superheating of vapour

Helps, to a limit, in binding process

Aids radiation heat transfer

e. Sulphur content

Typical range is 0.5 to 0.7 %

Sulphur

Affects clinkering and slagging tendencies

Corrodes chimney and other equipment such as air heaters and economizers

Limits exit flue gas temperature



Fixed Carbon

MoistureProximateAnalysis

Volatilematter

Ash

1.5 Ultimate analysis

Ultimate analysis is used to determine the elemental composition in terms of Carbon,

Hydrogen, Sulphur, Nitrogen and Oxygen by difference.

Determines the amount of :

Carbon

Hydrogen

Oxygen

Nitrogen

Sulphur

The ultimate analysis includes the various elemental chemical constituents such as Carbon,

Hydrogen, Oxygen, Nitrogen and Sulphur.

It is useful in determining the quantity of air required for combustion and the volume and

composition of combustion gases. This information is required for the calculation of flame

temperature and the flue gas duct design.

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Note: The above equation is valid for coal containing greater than 15% moisture content

The percentages can be reported by weight in a variety of different ways:

As sampled (as received) - exactly as the sample came to the lab

Dry - based on the air dried sample (not completely dried)

Dry, Ash free - based on the air dried sample with ash removed

Dry, Mineral Matter Free (DMMF) - based on the air dried sample with all mineral (inorganic)

matter removed

Mineral matter is not directly measured but may be obtained by one of a number of empirical

formulae based on the ultimate and proximate analysis. Further empirical relationships are

also possible between carbon, hydrogen, oxygen and CV.

Relation between Ultimate analysis and proximate analysis

% C = 0.97C+ 0.7( VM-0.1A)-M (0.6-0.01M)

% H = 0.036C + 0.086 ( VM-0.1 x A)-0.035M2 (1-0.02M)

% N = 2.10-0.020VM

C = % of fixed carbon

Where A = % of ash

VM = % of Volatile matter

M = % of Moisture

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1.6 Grindability

This is particularly important if a coal is to be burnt in the pulverized state. In this case,

significant work must be done in order to reduce the coal down to particles of sufficient size

for combustion. The Hard grove grindability index is calculated by applying a standard amount

of work on a sample of coal and determining the increase in surface area. The value, G is

based on the fraction of coal of initially sieved with a size 16 mesh, passing through mesh size

30 after a standard mill. The value ranges between 20 and 100 for most coals. The easiest to

grind being the bright, bituminous coals.

Hard grove grindability Index measurement (HGI)

With this technique the hardness of coal can be determined. The sample is first ground and

sieved to a specific size, and ground in the HGI equipment under special conditions.

The grindability value obtained is compared with a calibration curve based on international

standard tests. The hardness gives information about the energy consumption when grinding

coal. A low HGI value indicates a hard coal, which will require more energy for grinding, than

a coal of high HGI value.

1.7 Use of coal in Power Generation

In our group units like Hindalco, Renusagar power division, Grasim Nagda, coal is mainly

used for power generation.



1.8 Use of coal in Cement Industries

In Rajashree Cement, Awarpur Cement, Aditya Cement and Vikram Cement coal is used for

cement making along with power generation.

Coal quality is a vital factor in determining plant efficiency. It not only affects the overall

profit margin but also contributes to other significant problems, if quality of coal is poor.

1.9.1 Common problems of power plants due to poor and inconsistent raw coal

quality are listed below:

Damage to conveyor belts and crusher elements

Frequent choking of chutes and feeders

Reduced pulverizing capacity of the mills

Higher erosion of grinding elements

Reduced availability of mills due to higher outages

Reduced flame stability requiring additional oil support

Typical Flow Diagram of Clinker Production

1.9 Effect of coal quality on power plant performance



Slagging and fouling of the water walls

Faster erosion at the coal burners and flue gas path

Increased requirement of land for dumping of ash and ash handling equipment

Reduced Plant Load Factor (PLF) as well as reduced station thermal efficiency

Higher emissions and related environmental impacts.

Several other operational problems may also arise due to poor and inconsistent

quality of coal.

1.9.2 Benefits of washed coals:

Some of the well recognized benefits arising from combustion of washed coal in thermal

power stations are :

Reduction in:

Emissions into the atmosphere

Ash handling and disposal costs

Requirement of oil support

Load on transportation system

Operating and maintenance costs in existing plants

Capital cost of new plants

Increase in:

Thermal efficiency

Plant availability

Plant output



Sl. No Description Testing Standards Contents

1.0 Proximate analysis Moisture

Volatile MatterIS : 1350 Part I 1984 Fixed Carbon

Ash

2.0 Ultimate analysisIS : 1350 Part IV

Carbon

Hydrogen

IS : 1350 Part IVNitrogen

Oxygen

IS : 1350 Part III Sulphur

3.0 Calorific Value IS : 1350 Part II Calorific Value

4.0 Hardgrove Grindabilty Index IS : 4433 1979 Hard grove Grindability Index

5.0 Sieve analysis ASTM D 197 Determination of fineness of coal

6.0 Abrasion Index IS : 9949 1986 Determination of abrasiveness of coal

1.0 B TESTING STANDARDS FOR COAL AND COKE

Testing standards :

1.0 A COAL QUALITY ANALYSIS FLOW DIAGRAM

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HINDALCO - RENUSAGAR POWER DIVISION :

1.0 C FLOW DIAGRAM OF COAL SAMPLING, QUALITY CHECK POINTS

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1.0 D RAJASHREE CEMENT - COAL SAMPLING AND ANALYSIS FLOWDIAGRAM

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1.0E AWARPUR CEMENT WORKS: FLOW DIAGRAM OF COAL SAMPLING,QUALITY CHECK POINTS

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2. COAL SAMPLING

Coal is a highly heterogeneous substance in terms of the inorganic and organic constituents and

exhibits wide variability with respect to size and chemical composition of the particles. An estimation

of the true value of the desired parameters of a bulk material, to a certain degree of confidence,

through analysis on a few grams of test sample is definitely a daunting problem. The basic purpose

of collecting and preparing a sample of coal is to obtain a test sample which when analyzed will give

the test results representative of the lot sampled.

In order that the sample represents the lot from which it is taken, it is collected by taking a definite

number of increments distributed throughout the whole volume of coal.

The procedure for sampling will, however, differ with the purpose and method of sampling. Samples

may be required for technical evaluation, process control, and quality control or for commercial

transactions. For quality assessment of coals from new sources, samples are to be drawn from

in-situ coal seams, either as rectangular blocks or pillars cut from full seam height, or from seam

channels or from borehole cores.

To check the quality of coal consignments, it is desirable to get the sample from conveyor belts. The

reference method of ‘stopped belt’ sampling is often implemented to standardize the mechanical

automatic sampling system.

Quality monitoring of coal is an important activity for any commercial transactions between the

consumers and the producers.

The sampling procedure will depend mainly on the nature of sample collection i.e. by mechanical

or manual means, from moving belt or from stationary lots like wagons, stockpiles, etc. Normally

any sampling scheme is supposed to confirm to relevant national or international standards. However,

due to cost and time constraints, very often some changes are made in the method of sampling

jointly by the seller and the purchaser. It is a known fact that about 80% of the total variances

involved at the different stages of sample collection, preparation and analysis comes from errors

during its collection only.

2.1 General principles of Sampling

The main requirements for coal sampling are,

All particles of coal in the lot to be sampled are accessible to the sampling equipment and

each individual particle shall have an equal probability of being selected and included in

the sample.



The dimension of the sampling device used should be sufficient to allow the largest particle

to pass freely into it.

The first stage of sampling known as primary increments is the collection of an adequate

number of coal portions from positions distributed over the entire lot to take care of the

variability of the coal. The primary increments are then combined into a sample, as taken

or after reducing the mass of the sample to a manageable size. From this gross sample, the

required number and types of test samples are prepared by a series of processes jointly

known as sample preparation.

The minimum mass of the gross sample should be sufficient to enable particles to be

present in the same proportions as in the lot of coal from which it is taken.

To ensure that the result obtained has the required precision, the following issues are to

be considered.

Variability of coal

Number of samples from a lot

Number of increments comprising each sample

Mass of sample relative to the nominal top size

The ideal method of sampling is the stopped belt method, which is considered free of bias. As

implementation of such method will affect the continuity of plant operations, it is not always

practicable for routine sampling. However, any mechanical sampling device needs to be checked

for bias by comparing with the results from stopped belt reference method

2.2 General procedure for establishing a sampling scheme

1 Decide the purpose for which the samples are taken e.g. plant performance evaluation,

process control, commercial transactions etc.

2 Identify the quality parameters to be determined, i.e. general analysis, total moisture, size

analysis, washability, etc.

3 Catagorize the size of coal in three parts i) small [0-2”] ii) large coal [2 - 6”] iii) Run of

mine coal [0-9”]

4 Define the lot .



4 Define the precision required

5 Decide whether continuous or intermittent sampling is required

6 Determine the number of sub-lots and the number of increments per sub lot to achieve the

required precision.

7 Determine or estimate the nominal top size of the coal

8 Determine the minimum mass per increment and the minimum mass of the total sample

9 Decide on the method of combining the different increments to produce the gross sample

10 Decide on drawing common or separate samples, for general analysis and moisture

2.3 Design of sampling scheme

Sampling scheme has to be designed based on the purpose of sampling and after ascertaining

at what stage of coal handling operation the sample is required.

Division of lots: A lot may be sampled as a whole or a series of sub lots. Each sub lot will

constitute one sample.

Basis of sampling: It can be either time basis or mass basis. In time basis the sampling

interval is defined in minutes/seconds and mass is proportional to the flow rate, whereas

in mass basis the interval is defined in tonne and the mass of increments is uniform.

Accuracy: In all methods of sampling, sample preparation and analysis, errors may be

introduced at every stage and the measured value may differ from the true value of the

parameter. As the true value is not exactly known it is difficult to assess the accuracy of

the results, but an estimation of accuracy of the results can always be made.

Decide required accuracy precision for each parameter of a lot and then the number of

sub-lots, number and mass of increment are to be estimated.

2.4 Joint sampling

Normally, joint sampling is carried out at the loading end by the representatives of the producer

and the customer, following a methodology mutually agreed upon by both parties. Depending

on the agreement, the loading point results can be taken exclusively for commercial transactions.

In some cases the mean value of the results of joint sampling at both the loading and unloading



ends is considered. The variance values in the quality parameters are often defined, beyond

which several bonus/penalty clauses are imposed. What needs to be stressed is whether the

variance value identified is compatible with the sampling scheme. More clearly, whether the

variation in the value lies within the precision limit that can be achieved through the

implementation of a particular sampling scheme. This requires periodic testing, which

unfortunately is rarely practiced in India.

It is a common experience that in spite of joint sampling, there often exist wide discrepancies

in the results at the two different ends. There may be multiple reasons for this:-

Procedures agreed for sampling and sample preparation are not followed at the two ends.

In case of manual sampling human discretion becomes a significant factor

Deviation from the procedures identified in the agreement

The level of accuracy required / agreed upon remained undefined, while designing the

sampling scheme.

2.5 Auto Sampling:

To get a correct assessment of the quality parameters, it is recommended that

sampling should be done through auto mechanical sampling systems. Immediate

steps need to be taken to bring the existing Auto mechanical sampling system in

working conditions, followed by testing of bias. The system should be studied for a

prolonged period to identify its limitations and constraints.

PRIMARY SAMPLERSAMPLING SYSTEMS FOR CRUSHED COAL (-) 20mm



2.6 Dust Suppression system:

The Dust Suppression System is meant to suppress the

coal dust generated during transfer of coal at feed/

discharge points of conveyors in various transfer points.

There are several existing methods of controlling dust

but many are ineffective, costly and have detrimental

effects on plant and machinery. An effective system for

the control of fugitive dust in industry should meet the

following objectives.

1. Must be efficient to meet Health and

Safety requirements.

2. It should be practical and simple in operation.

3. Have low initial cost.

4. Have low operating costs.

5. No adverse effects on product quality or plant and machinery should be created.

At Rajashree Cement Works, dust suppression system is installed at Wagon tippler area.

This system is designed in-house by plant team and effectively working as a means to

suppress the coal dust at the time of unloading as well as feeding to the respective units.

Water spray is being done on the reclaimer belt having material sensors to prevent escaping

the fine dust of coal.

System consists of high pressure water pump, water storage tanks to store sufficient amount

of water for a day operation and high pressure jet nozzles to spray water in mist form.

Salient features of the system installed at Rajashree Cement :

1. System prevents to escape the fine coal particles in the atmosphere, mixes coal particles

with water mist and collect in coal bunker. Thus substantial amount of fine coal is

recovered.

2. System uses recycled water of treatment plant. There is no additional requirement of

fresh water.

3. Clean and Environment friendly atmosphere.



3. PROCEDURE FOR DETERMINATION OF MOISTURE

3.1 Purpose

To know the moisture content of coal, crushed to pass through 212 micron IS sieve.

3.2 Scope

This method is applicable to all types of coals.

3.3 Reference

IS -1350 (Part -1) 1984

3.4 Definition

It is the moisture in coal which has been air dried under the laboratory atmosphere

condition prior to analysis and determined as a part of proximate analysis of coal.

3.5 Procedure

For detailed Procedure please refer to SOP- Coal Loss Accounting



4. PROCEDURE FOR DETERMINATION OF FIXED CARBON PERCENTAGE IN COAL

4.1 Purpose

To know the carbon content of coal chemically bounded in coal besides the carbon which is

associated with volatile matter.

4.2 Scope


4.3 Reference

IS -1350 (Part -1) 1984

4.4 Definition

Fixed carbon (percent) is the figure obtained by subtracting from 100 the sum of the percentage

moisture, volatile matter and ash of the coal.

4.5 Procedure

4.5.1 The coal sample shall be ground to pass through 212 micron sieve for laboratory analysis.

4.5.2 The percentage of moisture in coal sample shall be determined.

4.5.3 The percentage of ash in coal sample shall be determined.

4.5.4 The percentage of volatile matter in coal sample shall be determined.

4.5.5 The percentage of fixed carbon shall be calculated as follows:

% Fixed Carbon = 100 - (Moisture %+Ash %+Volatile matter %)



5. PROCEDURE OF DETERMINATION OF VOLATILE MATTER IN COAL

5.1 Purpose

For assessment the use for which coal is suitable and for classification also.

5.2 Scope


5.3 Reference

IS -1350 (Part -1) 1984

5.4 Definition

The Volatile matter is the loss in mass less than due to moisture, when heated under standard

conditions.

5.0 Procedure

5.5.1 The volatile matter determination crucible shall be put (with lid and plunger) in stand

5.5.2 The crucible with stand shall be placed in furnace at a temperature of 900 ± 10º C for

7 minutes.

5.5.3 The crucible with stand shall be removed from the furnace and cooled first on a metal

and then in desicator for 20 minutes.

5.5.4 The crucible (with lid and plunger ) shall be weighed and 1 gm of coal sample (ground

to pass 212 micron IS sieve) shall be weighed in crucible.

5.5.5 The coal sample shall be pressed with plunger and the crucible shall be covered with

lid.

5.5.6 The crucible shall be put in stand.



5.5.7 The crucible with stand shall be placed in furnace at a temperature of 900 ± 10º C for

7 minutes.

5.5.8 The crucible shall be removed, cooled and weighed as mentioned in clause 5.5.4

5.5.9 The volatile matter of the coal sample shall be calculated as given below :

Calculation

% Volatile matter ( )

( )2 3

02 1

100 M -MV= -M

M -M

Where M0= % moisture content in the sample

M1 = Mass in gm of empty crucible with lid and plunger

M2 = Mass in gm of crucible with lid and plunger plus mass of coal sample before heating

M3 = Mass in gm of crucible with lid and plunger plus mass of coal sample after heating



6. PROCEDURE OF DETERMINATION OF ASH CONTENT IN COAL

6.1 Purpose

To check the quality of coal and to calculate useful heat value (UHV) of coal for grade

specification

6.2 Scope

This method is applicable to all types of coal.

6.3 Reference

IS -1350 (Part -1) 1984

6.4 Definition

Ash is the organic residue left when the powdered sample of coal has been incinerated in air in

open dish until it no longer change in weight at 815 ± 10º C.

6.5 Procedure

6.5.1 The air dried laboratory coal sample shall be thoroughly mixed and ground to pass

212 micron IS sieve

6.5.2 A clean dry empty ash determination silica crucible shall be weighed.

6.5.3 Approximately 1 gm of coal shall be weighed.

6.5.4 The coal shall be spread on the crucible so that it does not exceed 0.15 gm/cm2

6.5.5 The uncovered dish shall be inserted into the muffle furnace at room temperature.

6.5.6 The temperature shall be raised to 500º C in 30 minutes and to 815 ± 10º C in 30 to

60 minutes and shall be maintained at this temperature for 60 minutes.

6.5.7 The crucible shall be removed from furnace and shall be allowed to cool first on a cold

metal plate for 10 minutes and finally in a desicator.



6.5.8 It shall be weighed after 20 minutes.

6.5.9 It shall be reignited at the same temperature until the change in mass of ash shall be

less than 0.001 gm.

6.5.10 The ash shall be brushed and the empty crucible shall be reweighed.

6.5.11 The mass of ash shall be obtained by difference.

6.5.12 The percentage of ash content shall be calculated as given herein under :

Calculation

Ash % by mass = 100X (M3 – M

4)/ (M

2 – M

1)

Where,

M1

is the mass in gm of crucible

M2

is the mass in gm of crucible +mass in gm of coal sample

M3 is the mass in gm of crucible and ash

M4 is the mass in gm of crucible after brushing out the ash and on reweighing



7. PROCEDURE OF DETERMINATION OF CALORIFIC VALUE

7.1 Purpose

To check the quality of coal and to calculate calorific value of coal.

7.2 Scope

This standard prescribes the methods of test for coal and coke relating to the determination of

calorific value

7.3 Terminology

a. Gross calorific value –

Number of heat units liberated when a unit mass of fuel is burnt at constant volume in oxygen

saturated with water vapour, the original material and final products being at approximately

25 0C. The residual products are taken as carbon dioxide, sulphur dioxide, nitrogen and water;

the residual water other than that originally present at vapour, being in the liquid state

To convert gross calorific value to net calorific value.

NCV = GCV -53 * H

Where

NCV = Net calorific value in Kcal/kg

GCV = Gross calorific value in Kcal/kg

H = Percentage of hydrogen present in the coal sample, including hydrogen of moisture and

of water constitution

b. Net Calorific value

Number of heat units liberated when a unit mass of the fuel is burnt at constant volume in

oxygen saturated with water vapour, the original and final materials being at approximately

250 C. The residual products are taken as carbon dioxide, sulphur dioxide, nitrogen and water

vapour.



7.4 Sampling –

7.4.1 Methods of sampling -As per IS: 436(Part 1)-1964 for coal and IS: 436(Part II)-1965

for Coke

7.4.2 Preparation of samples for test

7.4.2.0 General: It is expected that methods of sampling prescribed in IS:

436(Part 1)-1964 for coal and IS: 436(Part II)-1965 shall have been followed

in the preparation of samples sent to laboratory.

7.4.2.1 The samples prepared in accordance with IS: 436(Part 1)-1964 for coal and

IS: 436(Part II)-1965 shall be in sealed containers and shall consist of the

following:

A) Analysis sample of about 300 g of air dried coal or coke, ground to pass

212 micron IS sieve (see IS -460-1962)

B) Special moisture sample of 1 kg of coal or 2.5 kg of coke, crushed to pass

12.5 mm square- mesh screen (see IS: 460- 1992) to be sent in duplicate.

7.4.2.2 Where air –drying has been adopted in the preparation of the samples, the

percentage loss of moisture in this operation shall be required to be recorded

on the label together with the method of sampling used.

7.4.2.3 Samples received in the laboratory, if already ground to pass 212 micron IS

sieve, shall be re- sieved to verify that all the material passes the sieve, and

then air – dried for 24 hours and mixed and bottled as above.

7.5 Calorific value of coal and coke

7.5.0 General – Two methods have been described to determine the calorific value of coal

and coke. They are: (a) making use of calorimetric bomb immersed in a static or

isothermal water jacket. (b) Making use of calorimeter bomb immersed in an adiabatic

jacket.

7.5.0.1 The calorific value as determined in these methods is the gross calorific value

of coal and coke at constant volume expressed in calories per gram.



7.5.0.2 Temperature dependence of calorific value –the calorific value of coal and

coke decreases with increase of temperature. The magnitude of dependence

varies between 0.1 and 0.3 cal/g0C, the lower value being for anthracites;

correction for variation in temperature of determination is, therefore, usually

negligible.

7.5.1 Principle – The coal or coke is burned in a bomb calorimeter of known heat capacity.

The principal observation is that of a temperature rise which, when corrected for the

errors of the thermometer and multiplied by the effective heat capacity at the mean

temperature of the chief period, gives the heat release. Further, allowance is necessary

for

a) Cooling loss

b) Heat gain due to heat released by the ignition system

c) Heat of formation of sulphuric and nitric acids from sulphur dioxide and

nitrogen.

7.5.2 Apparatus: Details are as per IS 1350(Part II) -1970

7.5.2.1 Combustion bomb

7.5.2.2 Calorimeter vessel

7.5.2.3 Water jacket

7.5.2.4 Stirring arrangement

7.5.2.5 Thermometer

7.5.2.6 Thermometer viewer

7.5.2.7 Crucible

7.5.2.8 Ignition circuit5.2.9 Timer

7.5.2.9 Pressure regulator and pressure gauge

7.5.3 Reagents : Details are as per IS 1350(Part II) -1970



7.5.4 Isothermal calorimeter Method

7.5.4.1.0 Coal used for the determination of calorific value is the analysis sample

ground to pass through 212 micron IS sieve. The sample is exposed in a

thin layer for the minimum time necessary for the moisture content to

reach equilibrium with the laboratory atmosphere.

7.5.4.1.1 Weigh the crucible to the nearest 0.1 mg and introduce into it in sufficient

quantity of the samples to cause a temperature rise of 2 0 to 3 0 C. Weigh

the crucible and contents to determine the weight of sample taken. Also

determine the moisture of the sample at the same time.

7.5.4.1.2 Connect a piece of firing wire rigidly across the terminals of the bomb.

Tie a known weight of cotton to the firing wire and arrange the ends of the

cotton so that they touch the sample.

7.5.4.1.3 Put 1 ml of distilled water in the bomb. Assemble the bomb and charge it

slowly with oxygen to a pressure of (30 atm) without displacing the original

air. Put sufficient water in the calorimeter vessel to cover the flat upper

surface of the bomb cap. This quantity of water should be the same, within

1 g, as that used in determining the mean effective heat capacity. The

temperature of the water shall be about 2.50C lower than that of water

jacket.

7.5.4.1.4 Transfer the calorimeter vessel to the water jacket; lower the bomb into

the calorimeter vessel and check that the bomb is gas tight. If gas escapes

from the bomb, discard the test.

7.5.4.1.5 Assemble, start up the apparatus and keep the stirrer and the circulation

arrangements in continuous operation throughout the determination. Use

a constant rate of stirring. After an interval of not less than ten minutes,

read the temperature to .0010C and continue the readings for five minutes,

that is, the preliminary period, at equal intervals of not more than one

minute, tapping the thermometer lightly during 10 seconds prior to each

reading. If, over a period of five minutes, the average deviation is less

than 0.000 72 0C per minute, close the battery circuit momentarily to fire

the charge and continue to those of the preliminary period. If the rate of



change of temperature is not constant within this limit, extend the

preliminary period until it is constant.

7.5.4.1.6 In the chief period, which extends from the instant of firing until the time

after which the rate of change of temperature again becomes constant,

take the earlier readings to the nearest 0.010C. Resume the readings to this

precision as soon as possible. Determine the rate of change in the after

period (which follows the chief period) by taking readings at 1 minute

intervals for at least five, preferably ten minutes.

7.5.4.1.7 Remove the bomb from the calorimeter vessel, release the pressure and

dismantle the bomb. Examine the bomb interior and discard the test if

unburnt sample or sooty deposits are found.

7.5.4.1.8 Wash the contents of the bomb into a beaker with distilled water. Wash

the underside of the bomb cap and the outside of the crucible with the

distilled water; add the washings to the beaker. Dilute to approximately

100 ml and boil to expel carbon dioxide. While still hot, titrate with standard

barium oxide solution using phenopthalein solution as indicator. Add 20

ml of sodium carbonate, warm, filter and wash the precipitate with distilled

water. When cold, titrate the filtrate with the hydrochloric acid solution,

using the methyl orange solution as indicator, ignoring the phenopthalein

color change.

7.5.4.2 Corrections –The followings corrections are made to the experimental observations.

7.5.4.2.1 Thermometer corrections

7.5.4.2.2 Cooling correction

a) The Regnault- Pfaundler( R-P) correction

b) Whitaker correction

7.5.4.2.3 Heat of ignition – the heat release from the cotton and firing wire is restricted

from the total heat release. The heat release from the cotton is calculated

from the weight, after drying at 1050C, of a known length of cotton thread,

and using the calorific value of a cellulose (4180 cal/g). Determine the weight

of a piece of wire equal in length to the distance between the poles of the



bomb, and calculate the heat release by allowing 335cal/g for nickel-

chromium wire, or 100 cal/g for platinum wire.

7.5.4.2.4 Heat of formation of acids – The heat gain due to the formation of sulphuric

acid and nitric acid is subtracted from the total heat released. These

corrections amount to 3.6cal/ml of 0.1 N sulphuric acid and 1.43 cal/ml of

0.1 N nitric acid present in the bomb washing and calculated as follows:

Sulphuric acid correction = 3.6 (a + b – 20) cal; and

Nitric acid correction =1.43 (20-a) cal;

Where

a = vol in ml of 0.1 N hydrochloric acid used

b = vol in ml of 0.1 N barium hydroxide used

7.5.4.2.5 Correction for unburnt carbon

If unburnt carbon is suspected, its heat equivalent, on the basis of 1 mg of

carbon equals 8 calories shall be added to the determined heat release.

Unburned carbon is determined as the loss in weight on ignition of the residue

from the crucible.

7.5.4.3 Calculation – as per IS 1350(Part II) -1970



8. PROCEDURE FOR DETERMINATION OF HARDGROVE GRINDABILITY INDEX OF COAL

8.1 Purpose

To know the properties like hardness, strength and to estimate the coal behavior with respect

to coalmill/pulverizer.

8.2 Scope

This method is applicable to all types of coals except brown coal and lignite..

8.3 Reference

IS – 4433 -1979

8.4 Definition

A prepared sample of coal is ground in a standard laboratory mill under defined conditions.

Hardgrove grindability index is calculated by the standard formula as per IS standards.

8.5 Sampling

Sample collection and preparation shall be in accordance with IS 436 (Part 1/ Sec 1) 1964

Except initial crushing shall be to 4.75 mm instead of 10 mm. Final coal sample of about 1kg

may be obtained by sample divider of suitable size and capacity.

8.6 Procedure

8.6.1 Before test grindability machine should be thoroughly cleaned and space the balls as

evenly as possible around the grinding bowl.

8.6.2 Sample of about 50± 0.01 gm prepared as per IS 436 (Part 1/ Sec 1) 1964 shall be

distributed evenly in grinding bowl surface is smoothened. Fasten the bowl and

assemble the top grinding ring and preset the counter and automatic stopping device

so that machine can operate for 60±0.25 revolutions.



8.6.3 Now switch on the apparatus

8.6.4 When rotation is stopped switch off machine and dismantle the bowl.

8.6.5 Empty the grinding balls and ground coal on protective sieve. Also brush any coal

from the bowl and the balls into the protective sieve setting them aside.

8.6.6 Brush any coal and dust from the inside and underside of the protective sieve into 75

micron sieve and set it aside.

8.6.7 Replace the cover on the 75 micron sieve. Shake the assembled pan, 75 micron sieve

and cover for 10 minutes. Carefully brush any coal dust from the underside of 75

micron sieve into the pan. Repeat this application for two more times for a period of 5

minutes each. Clean the underside of 75 micron sieve after each repetition.

8.6.8 Weigh separately to the nearest 0.01 gm of the coal retained on the 75 micron sieve and

the coal passing the 75 micron sieve. If the sum of these masses differs by more than

0.3 gm from the initial mass of 50± 0.01 gm, the test shall be rejected.

8.6.9 Calculations

8.6.9.1 Hard Grove grindability index can be calculated using the formula

HGI = 13 + 6.93 M

Where

M = mass of the test sample passing through 75 micron sieve after grinding.

In practice M is obtained by deducting from 50 gm of mass of ground sample

retained on 75 micron sieve.

In IS 4433 -1979 a standard table to ascertain the value of HGI from the

experimental values of mass of the coal particles over 75 microns is also

provided



9. PROCEDURE OF SAMPLING AND FINENESS TEST OF PULVERIZED COAL

9.1 Purpose

This Test method covers the determination of the fineness by sieve analysis of coal sampled

from a dry pulverizing operation.

9.2 Scope

This method is applicable to dry pulverized coal and not applicable to products of wet milling

or to fines that have clustered into an agglomerated mass.

9.3 Reference

ASTM D 197 -87

9.4 Definition

This test provides a means for assisting in the evaluation of pulverizers and Pulverizers system

in terms of fineness specifications.

9.5 Sampling, storage system

9.5.1 In the pulverized coal storage system, the coal after pulverized is conveyed into bins.

9.5.1.1 Collection of gross sample – Collect not less than ten increments of

representative pulverized coal preferably as it is being discharged from the

collector. This is best accomplished by collecting increments of not less than

50 g at regular intervals by means of scoop, dipper or a device capable of

removing increment from a specific location within the stream of pulverized

coal.

9.5.1.2 Preparation of the laboratory sample – A small riffle (sample divider) can be

used for mixing and dividing the sample by splitting. Mix the gross sample

by splitting and recombining the halves a minimum of two times. Divide the

sample amount by successive riffle splitting operations on one half of the

sample until the sample is divided to approximately 500 g for the laboratory

sample.



9.5.1.3 As an alternative to riffle mixing and splitting, the sample can be prepared as

follows: Place the gross sample on a sheet of rubber, plastic, or paper and

mix it by raising first one corner of the cloth and then the other so as to roll

the coal over and over at least 20 times. After mixing, divide the sample;

continue the operations of mixing and dividing until the sample is divided

sufficiently so that all of one of the divisions weighs approximately 500 g.

This shall constitute the laboratory sample.

9.6 Sampling, Direct feed system

9.6.1 In the direct feed system, the coal is pulverized and delivered to the furnace in

an air stream. It is difficult to obtain representative samples, as it is necessary

to sample the coal from a moving stream of coal –air mixture inside the pipe

between the pulverizer and furnace. It is preferable to collect such samples

from vertical pipes, as horizontal pipes a greater amount of segregation may

take place.

9.6.2 Apparatus for sample collection : It is very difficult to collect a representative

sample of solids from a moving coal air system, it is essential that an equipment

and sampling procedures are uniformly consistent to assure valid and

reproducible results. Recommended equipment and sampling arrangement are

shown in fig 1, 2 and 3



9.6.2.1 In figure recommended arrangement for sampling pulverized coal in a direct

fired system using a dustless sampling connection with an aspirator and a

cyclone collector. In collecting the sample, turn on the compressed air to the

dustless connection and adjust to give a balanced pressure at the connection.

Insert the sampling tip into the dustless connection with the tip facing directly

into the coal – air stream. Readjust the compressed air to give a balanced

pressure with the nozzle inserted. Traverse the fuel transport line across the

entire diameter of the pipe by moving at a uniform rate with the tip facing

directly into the coal – air stream. The aspirating air on the cyclone collector

may or may not be used, depending on the static pressure in the fuel transport

line.

9.6.2.2 Fig. 3 shows detailed dimension of a recommended sampling tip. The area

of the tip shown in is 12.7 mm by 24.1 mm or 306 mm2). which is the

projected area of the tip facing the coal –air stream.

9.6.3 Collection of gross sample as per ASTM D 197

9.7 Fineness Test

9. 7.1 Drying sample - Air dry the entire laboratory sample in a drying oven at 10 to 15º

above the room temperature. Continue the drying until the loss in weight is not more

than 0.1% /hour



9. 7.2 Dividing the sample – After air drying, divide the sample amount to 50 to 100 gm.

9.7.3 Sieve Test

9.7.3.1 Select the proper sieve sizes for the test and thoroughly clean each by carefully

brushing and tapping to assure that no solid particles from previous tests are trapped

in the meshes. Nest the sieves together with the coarsest mesh at the top and in

descending order with the finest mesh in the bottom of the nest to receive the undersize.

Place 45 to 55 g of coal weighed to 0.05 g on the top sieve and cover with a fitted

cover to prevent loss.

9.7.3.2 Place the assembled set into the sieving machine and make the necessary

adjustments for the sieving operation. Adjust the timer for a 10 minute period and start

the machine

9.7.3.3 At the end of sieving period, remove the stack, slip off the receiver pan, and

carefully brush into the pan receiver any particles that have adhered to the bottom

surface of the bottom sieve. Carefully transfer all of the pan contents into another

receptacle and return the clean pan receiver to the bottom of stacker sieves. Retain the

transferred fines for weighing

9.7.3.4 Return the stacked sieves to the sieving machine, set the timer for a 5 minute

period and start the machine. At the end of this interval, remove the stack and repeat

the procedure. However, this time collect the fines from the pan receiver and those

brushed from the under- surface of the sieve and weigh. When the collected fines from

the 5 minute sieving weigh less than 0.5 g, consider the sieving operation complete. If

the fine weigh in excess of 0.5g, reassemble the stack and repeat the sieving operation

at 2 minute intervals until less than 0.2 g of fines are collected for a 2 minute interval.

9.7.3.5 Combine the fines collected in all of the operations and weigh on a balance

sensitive to 0.01 g. Disassemble the sieves beginning with the largest. Material that

can be brushed from the bottom of a sieve shall be considered to be part of the sample

that has passed through that sieve. This material can be brushed directly onto the next

finer sieve. Material that is lodged in the sieve shall be considered a portion of the

sample that was retained on the sieve.



9.7.3.6 Weigh and record the amount of material collected from each sieve surface,

including the undersize material.

9.8 Calculations:

9.8.1 Calculate the fineness from the weights of the residues on the sieves, including the

undersize from the finest sieve, and express as percentage of weight of the original

sample. A difference between the original sample portion and cumulative sieve weight

is considered to be due to loss (or gain) of the undersize material and is so calculated.

If the loss is greater than 1% for coals having 75% or less undersize or is greater than

2% for coals having more than 75% undersize, discard the results and repeat the

determination.

9.9 Report:

The fineness test shall be reported as follows:

Retained on USA Passing Percentage %

Standard USA Standard

No 8 (2.36 mm) ———-

No 16 (2.36 mm) No 8 (2.36 mm)

No 30 (2.36 mm) No 16 (2.36 mm)

No 50 (2.36 mm) No 30 (2.36 mm)

No 100 (2.36 mm) No 50 (2.36 mm)

No 200 (2.36 mm) No 100 (2.36 mm)

No 325 (2.36 mm) No 200 (2.36 mm)

——- No 325 (2.36 mm)

9.10 Fineness test by hand sieving

9.10.1 For field testing or similar operations where a sieving machine is not available. The

test can be performed by a hand –sieving operation. The object of hand sieving

operation is to duplicate as nearly as possible the details of test as performed by

mechanical sieving.



This can be accomplished as below.

9.10.2 Prepare the sieves and the sample amount with the exception of placing the nest of

sieves into a sieving machine.

9.10.3 Instead, hold the nest of sieves with both hands and move back and forth in a slightly

circular orbit while resting on a ¼ inch (6.4 mm) plate (suggested dimensions 4 by

12 inch (100 X 300 mm)). With each movement, the stack is permitted to move over

the plate edge and tap the table surface. The above described manual movement is

designed to stimulate the rotation and tapping of machine sieving.



10. PROCEDURE OF SAMPLING OF COAL FROM TRUCKS DURING UNLOADING

10.1 Purpose

To know the quality parameters of coal transported by trucks.

10.2 Scope

This method is applicable for sampling of coal from trucks during unloading. Head of the

department shall ensure that the specified jobs are being carried out and corrective actions

are taken wherever required.

10.3 Reference

IS -436 (Part -1/ Sec 1) 1964

10.4 Definition

It is a sampling of coal to check the quality of coal during unloading in yard by trucks.

10.5 Environment and safety measures

10.5.1 Ensure use of nose mask and goggles during collection and preparation of coal

samples. Ensure proper ventilation by switching on exhaust fan.

10.5.2 Clean the work area, sampling plate, pastel and Mortar.

10.5.3 Mix the coal sample after several coning and quartering to make it homogenous.

10.5.4 After crushing the coal sample, make powder and pass through 212 micron sieve.

10.6 Procedure

10.6.1 For the purpose of sampling a lot shall be divided into sub-lots in conformity with

IS -436 (Part -1/ Sec 1) 1964

10.6.2 The gross sample from sub-lots shall be collected by suitable hand shovel in

conformity with IS – 436 (Part -1/ Sec 1) 1964



10.6.3 The total gross sample for a day shall be mixed together and shall be broken

manually to less than 5 cm and then reduced to 1/4th of original gross sample by

coning and quartering.

10.6.4 The reduced sample obtained shall be crushed to pass through 12.5 mm by jaw

crusher. About 1 kg of coal sample shall be collected for determination of moisture

and shall be kept in sealed container.

10.6.5 The crushed gross sample shall be again crushed to 3.35 mm by mill and reduced

to 2 kg by coning and quartering.

10.6.6 About 300 gm of so reduced coal shall be ground to pass through 212 microns IS

sieve for laboratory analysis.

10.6.7 The analysis shall be carried out for the determination of the following:

Moisture %

Ash %

Volatile Matter %

Fixed Carbon %

Gross Calorific value K Cal /kg



11. PROCEDURE FOR COLLECTION, PREPARATION AND ANALYSIS OF

SAMPLES FROM RAILWAY WAGONS OUTSIDE PLANT

11.1 Purpose

To know the quality (Moisture, ash, GCV) for fixation of prices.

11.2 Scope

This method is applicable for sampling of coal from railway wagon. It is also applicable to

imported coal transported through wagons.

11.3 Reference

IS – 436 Part -1/ Sec -1 of 1964 and as upgraded in Nov 1996

11.4 Definition

Since it is not possible to check every piece of coal in a consignment, laboratory tests are

carried out on a sample which represents the bulk of coal from which it was drawn.

11.5 Responsibility : Concerned Quality Department person

11.6 Procedure

A Collection of sample

(IS – 436 Part -1/ Sec -1 of 1964 and as upgraded in Nov 1996)

11.6.1 Making Sub- Lots

11.6.1.1 Average number of wagons in one rack ( lot) : 58

11.6.1.2 Average weight (MT) per rake (lot) : > 3000

11.6.1.3 No. of sub- lot shall be made as per IS standard : 6

(Clause 0.3.4.1 and 3.1)



11.6.1.4 No. of wagon in each lot

Sub-lot one (01) : 10 wagons (1 to 10 from power)

Sub-lot two (02) : 10 wagons (11 to 20 from power)

Sub-lot three (03) : 9 wagons (21 to 29 from power)

Sub-lot four (04) : 10 wagons (30 to 39 from power)

Sub-lot five (05) : 10 wagons (40 to 49 from power)

Sub-lot six (06) : 9 wagons (50 to 58 from power)

Note: If the wagons are more than 58 in nos. those will be added in sub – lot no.6

11.6.1.5 From each sub –lot 25% of wagon shall be selected i.e. 3 wagons from

each sub-lot.(As per clause 4.2.1 A)

11.6.2 Methods of Random Selection of Wagons

11.6.2.1 Random selection of wagons as per Appendix –A (clause 4.2.1 and 7.2)

shall be done.

11.6.2.2 Table no. 5 “Random Sample table” (as per clause A.2.1) shall be used.

11.6.2.3 Since no. of wagons are less than 100, 1st set of random nos. shall be

used.

(Random sample nos. for this purpose are reproduced and enclosed for

reference)

11.6.2.4 Random selection of wagons shall be done as follows :

i) For Sub-lot 1

Any no. between 1 and 10 shall be selected

Selected no. shall be located in the table.

Another two nos. shall be selected by moving left or right or

moving upwards /downwards and selecting nos. less than 10

All these selected nos. shall be arranged in a sequence.

This nos. shall become the wagon nos. from which the samples

shall be collected.



ii) For Sub- lot 2




moving upwards/downwards and selecting nos.between

11 and 20.



shall be collected.

iii) For Sub- lot 3




moving upwards /downwards and selecting nos. between

21 and 29.



shall be collected.

iv) For Sub- lot 4





30 and 39.





shall be collected.

v) For Sub- lot 5





40 and 49.



shall be collected.

vi) For Sub- lot 6





50 and 58.



shall be collected.

11.6.3 Methods of Sample collection

11.6.3.1 Samples shall be collected all through the process of unloading of coal.

11.6.3.2 Weight of each increment (kg) Approx. : 07 kg.

11.6.3.3 No. of increments (about 7 kg each) from each wagon : 16



11.6.3.4 Quantity of coal samples shall be collected from each wagon :

(16 x 7) kg = 112 (approx.)

11.6.3.5 These collections shall be filled in two bags of about 50 kg each (approx.)

11.6.3.6 Each bag shall be selected with proper sealing arrangement.

11.6.3.7 Sealing shall be done in presence of authorized person from chemical

Lab., Coal quality, Technical services department (whenever deputed)

and representative of Supplier /Clearing agent (If available on site)

11.6.3.8 Each bag shall be tagged for identification indicating the sub-lot no. and

wagon number from which the sample has been collected.

11.6.3.9 Quantity of coal sample shall be collected from each sub-lot (16x 7x3):

336 kg (approx.)

11.6.3.10 Quantity of coal sample shall be collected from each lot and rake

(16x 7x3x6) kg comprising between (35 to 40 bags) : < 2000(approx)

11.6.3.11 All collected sample bags (35 to 40 nos.) shall be shifted to Coal Testing

Laboratory at plant.

B Sample preparation (IS 436 part I Sec -1 1964)

1.0 All the bags (35 to 40 nos.) shall be unsealed and opened at Coal Testing

Laboratory under the supervision of authorized persons (Whenever deputed)

and the representative of supplier / clearing agent (If available)

2.0 All the collected samples shall be poured in one heap.

3.0 Sample preparation shall be done as per (IS 436 part I Sec -1 1964)



12. COAL QUALITY TESTING EQUIPMENTS

BOMB CALORIMETER

With Digital Beckman thermometer for finding out the Calorific value of

Coal, coke, etc. Complete with 25 essential accessories with factory

test certificate for Bomb. Also available With Printer Models. Also

available additional accessories like Oxygen empty Gas cylinder with

factory and Ministry of Explosive certificates, Two stage pressure regulator

for inlet and out going pressure.

JUNKER’S GAS CALORIMETER

The Calorimeter, pressure governor, non-recording Gas Flow meter in which calorific value is ascertained

from the rise of temperature imparted to a measured quantity of gas. Range 1000-26000 Kcal/m2, 120 –

300 BThu/C.ft. Consists of calorimeter, pressure governor, and non-recording 1-litre flow meter and is

supplied with 2 litres and 50 ml measuring jars, 3 Thermometers and flexible tubing.

JAW CRUSHER – LAB MODEL

For speeding up crushing of aggregates, ores, minerals, coal, coke, ceramic and other similar materials.

Jaw size: 100 * 150 mm, max. size of feed : 50 mm (approx.), Product discharge size : 5 mm to 15 mm,

capacity 100 to 200 kg (Based upon material). Complete with 3 HP motor, starter, V-belt, pulley drive and

mounting for 440V, 50 Hz AC mains.

HARDGROOVE GRINDABILITY TESTER

As per IS: 4433/1967. It is a miniature pulveriser employing the ball bearing principles of grinding. Supplied

with automatic revolution counter, weights and built-in reduction gear. Wired for 240V, single phase, 50

Hz. AC mains.

ROLL CRUSHER – LABORATORY MODEL

For crushing different ore samples and minerals. Roll size: dia 200 mm and length of rolls 100 mm. Feed

size 8 mm, product size 1 to 2 mm. For 440 V, 50 Hz, 3 phase AC.

MINERAL JIG – LABORATORY MODEL

Stroke length is variable between 0” to ¾” at 400 rpm approx. size of screen compartment 4” * 6”,



complete with a mild steel stand structure driven by ½” HP 200 V AC motor and one 8 mesh screen and

one trash screen for the screen box along with starter.

BALL MILL – LABORATORY MODEL

Internal dia. 18 * 18 long, opening of 150 mm width and 350 mm long (approx.) speed of rotation is 56 ±

2 RPM. 12 Nos. of 1 ¼” dia. Steel balls are supplied with the unit. For 440 V, 50 Hz AC, 3 phase operation.

PULVERISER – LABORATORY MODEL (6” MINI MILL)

Designed for powdering lab model Rotor with beaters mounted on shaft direct coupled with 1 HP 3 phase,

440V, 50 Hz AC. With screen and cotton bag. Designed for powdering lab coal samples to 72/100 mesh.

PROXIMATE ANALYSER

For coal and coke as per IS: 1350. Consists of carbon & Hydrogen Analyzer, Volatile matter determining

furnace, Ash determination furnace, Moisture determination Oven.

MUFFLE FURNACE – HIGH TEMPERATURE – ELECTRIC

With Digital temperature indicating-cum-controller, thermocouple, air break magnetic contactor, fuses.

Maximum temperature up to 1400°C and regular recommended temp. not to exceed 1300°C. Available in

various sizes.

Vibrating Screen

Shaker Screens

Rota Screen

Electromagnetic Screens

Vibratory Feeder (Electromagnetic type)

Magnetic separators (Electromagnetic type)

Magnetic separators (Permanent magnet type)

Magnetic Drum

Magnetic pulley



6200 Automatic Isoperibol Calorimeter

To determine the calorific value of coal

Model 6200 is a microprocessor controlled isoperibol oxygen bomb calorimeter which is widely used for

both routine and occasional calorific tests. It uses the time-tested Parr 1108 oxygen bomb and oval bucket

in a compact calorimeter, producing reliable results with good repeatability, but differing from the 1271

and 6300 Models in that the bomb and bucket both must be removed from the calorimeter and refilled

manually for each test, thereby requiring more of the operator’s time than the automatic and semi-automatic

models.

All sensors, controls and jacketing in the 6200 Calorimeter are built into a single, compact cabinet to

provide a self-contained operating unit consisting of:

A temperature-controlled water jacket with a built-in circulating system and an electric heater.

An 1108 oxygen bomb with an oval bucket which fits into the insulating water jacket.

A built-in semi-automatic system for charging the bomb with oxygen.

A high precision electronic thermometer.



A bright, color, touch screen display for data entry and operation control.

Special communication ports for printer, computer and network (LAN) connections.

Removable compact flash memory card slot for simple program updates and test report archiving.

Touch Screen

Precise Electronic Thermometry

Temperatures are measured with a high precision electronic thermometer using a specially designed

thermistor sensor sealed in a stainless steel probe which is fixed in the calorimeter cover. Measurements

are taken with 0.0001° resolution over a 20° to 40°C working range, with all readings shown in Celsius.

Effective Thermal Jacketing

Outstanding thermal jacketing is provided by a circulating water system driven by a built-in, high capacity

pump which maintains a continuous forced flow around the sides and bottom of the bucket chamber and

through the cover as well. The jacket temperature is held constant for isoperibol operation and no water

additions or waiting periods are required at the end of a run. A sealed immersion heater and a built-in heat

exchanger, both operated by the calorimeter controller, provide precise jacket temperature control.

A Reliable Oxygen Bomb

The Parr 1108 Oxygen Bomb furnished with the calorimeter will safely burn samples liberating up to

8000 calories per charge, using oxygen charging pressures up to 40 atm. An alternate 1108CL bomb with

superior resistance to chlorine and halogen acids is recommended for tests involving waste material and

chlorinated samples.



A Built-In Oxygen Filling System

To speed and simplify the bomb filling operation, the 6200 Calorimeter has a semi-automatic system for

charging the bomb with oxygen. Oxygen from a 1A commercial cylinder is connected to a microprocessor

controlled solenoid installed in the calorimeter. To fill the bomb, the operator simply slips the filling hose

connector onto the bomb inlet valve and pushes the touch screen to start the filling sequence. Filling then

proceeds automatically at a controlled rate to a pre-set pressure. Built- in safety provisions will prevent an

accidental overcharge.

Automatic Standardization

The 6200 Calorimeter will automatically generate its energy equivalent (EE) value from a series of

standardization tests, calculating a mean value from either (a) all standardization tests, or (b) from the last

10 operator designated tests for each bomb/bucket combination. The user can enter the maximum standard

deviation he will accept and the calorimeter will advise him if his tests fail to meet this criteria. Energy

equivalent values for up to four bomb/bucket combinations can be stored in the computer.

Many User Options

Although specific procedures are recommended, various options are available to the user:

Program parameters can be adjusted to accommodate unusual sample sizes and precision

requirements.

The calorimeter can be programmed to accommodate any titrant concentrations selected by the user.

Calorific values can be reported in any of several measurement units.

The calorimeter program can be adjusted to compensate for the subtle differences in the way acid

correction values are handled in ASTM, BS, DIN and ISO methods.

Program controls can be protected from inadvertent changes.

A bomb usage tally can be maintained to notify the user when each bomb should be serviced.

Multiple Language Options

Parr Model 6200 can be set to provide the programming options, operating menus, reports and error

messages in the following choice of languages: English, French, and German.



Automatic Data Transfer

The calorimeter is equipped with RS232C communication ports for reporting to a printer and receiving

sample weights from an analytical balance. Transferring results to a laboratory computer is accomplished

using an Ethernet connection using standard network protocols.

Compatible Modular Design

The 6200 Calorimeter is fully compatible with existing 1108 Parr Bombs and closed-circuit water handling

systems making it easy to fit the instrument into an existing laboratory set-up. A modular design, with the

controller electronics assembled in a removable chassis, simplifies maintenance.

Accessories for the 6200 Calorimeter

1757 Printer

1757 Printer

Operating results and operator messages are displayed clearly on the touch screen for review and action.

Many users who connect their calorimeter to a computer will choose to print their results from their

computer and will not need a dedicated printer for their calorimeter. For users who prefer to have a

dedicated printer at the calorimeter, Parr offers the compact model 1757 Printer. The printer port can be

configured to work with many other printers with serial communications that the user may choose. The

1757 printer is a compact, dot matrix printer setup for 40- character/line reports. It is the default printer for

the 6200 calorimeter. It is housed in a separate 5.5 inches wide, 9 inches deep and 7 inches high. It

operates from its own power supply.

6510 Water Handling System

For users who wish to operate their 6200 Calorimeter on a closed loop system, the 6510 Water Handling

System incorporates a precision pipette for measuring and delivering the water for the calorimeter bucket

at the same fixed temperature for each test. This water handling system incorporates a built-in, compact,



solid-state water chiller. As a result, no external water chiller is required. It also provides cooling water to

the jacket of the 6200 calorimeter, if required.

1563 Water Handling System

The 1563 Water Handling System is designed to work with a separate water cooler. The Parr 1552 Cooler

is recommended for this purpose. The 1563 Water Handling System incorporates a precision pipette for

measuring and delivering the water for the calorimeter bucket at the same fixed temperature for each test.

This unit is capable of supporting and supplying temperature controlled water for up to two calorimeters.

Extra Bomb and Bucket

An extra A391DD Calorimetric Bucket and 1108 Oxygen Bomb will greatly improve the throughput of

the 6200 Calorimeter as they permit the next test to be prepared in advance.

Coal Abrasion Index tester

Coal handling material suffers abrasive wear losses due to abrasion

characteristic of coal. Resistance to coal abrasive wear at ambient and

elevated temperature can be found with the help of this equipment

Application

This tester can be used to assess the relative abrasive wear resistance

characteristic of material to help selection of right type of material of

construction for mixing, crushing, grinding and burning equipment.

Standard

BIS 9949-1986

Features

Auto shut off after preset revolutions.

Easy to clean chamber.

Dust confinement.

Optional heating of chamber for high temperature tests.



Specifications

Parameter Unit Min Max Remarks

Test Speed RPM 0 1500 Variable

Revolution Counter 1 9999 Presetable in steps of one

Temperature oC Ambient 400oC Optional

Power V/HZ/PH/KVA 415/50/3/3 Other voltages on request

Contact Details:

Ducom Instruments Pvt. Ltd.

477/A, 4th Phase,

Peenya Industrial Area,

Bangalore-560058., India.

Phone: +91 80 4152 5162

Fax: +91 80 4152 5162

Email: [email protected] or [email protected]



13. PROCEDURE FOR DETERMINATION OF BOILER EFFICIENCY

13.1 Overview

The performance of boiler, like efficiency and evaporation ratio reduces with time due to poor

combustion, heat transfer, surface fouling and poor operation and maintenance practices. Even

for a new boiler, reasons such as deteriorating fuel (like coal) quality, water quality etc. can

result in poor boiler performance.

A boiler efficiency test helps us to find out the deviation of boiler efficiency from the design

efficiency.

Any observed abnormal deviations could therefore be investigated to pinpoint the problem

area for necessary corrective action.

13.2 Purpose:

The main purpose of evaluation of boiler efficiency

is to determine the current efficiency level and to

compare it with design efficiency. It is an indicator

of day to day variation in boiler efficiency with

respect to design value.

13.3 Reference standards: IS 8753, Indian standardsfor boiler efficiency testing.

13.4 Boiler Efficiency

Thermal efficiency of boiler is defined as the percentage of heat input that is effectively utilized

to generate steam. There are two methods of assessing the boiler efficiency by using coal as

fuel.

13.4.1 Direct Method

In this method energy gain of the working fluid (water and steam) is compared with the energy

content of the boiler fuel (coal, oil etc)

13.4.2 Indirect Method

In this method efficiency calculation is based on the difference between the losses and the

energy input of boiler fuel.



13.5 Direct Method

This is also known as “Input-output method”. This is due to the fact that it requires only the

useful output (steam) and the heat input (i.e. coal) for evaluating the efficiency.

Fig.1 Heat balance diagram by direct method

The efficiency can be evaluated by using the formula

Boiler efficiency = (Heat output / Heat input) ×100

Following are the parameters to be monitored to evaluate the boiler efficiency by Direct method.

Sl.No. Parameters to be monitored Unit

1 Quantity of steam generated per hour Kg/hr

2 Quantity of fuel used per hour ( for coal) Kg/hr

3 Working pressure kg/cm2(g)

4 superheat temperature ,if any OC

5 Temperature of feed water OC

6 Type of fuel and gross calorific value of the fuel (coal) kCal/kg of fuel

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Boiler efficiency (ηηηηη) = Qx (hg -hf) /q x GCV

Where,

Q= Quantity of steam generated per hour in Kg/hr

hg =Enthalpy of saturated steam in kCal/kg of steam

hf= Enthalpy of feed water in kCal/kg of water

q = Quantity of fuel used per hour (for coal) in Kg/hr

GCV = Gross calorific value of coal (kCal/kg of coal)

Note: Boiler may not generate 100% saturated dry steam and there may be some amount of

wetness in the steam.

It is very important to measure accurate flow of coal or any solid fuel. The measurement

must be based on mass, which means that bulky apparatus must be set up on the boilerhouse floor. Samples must be taken and bagged throughout the test, the bags sealed and

sent to laboratory for analysis and calorific value determination. In latest practices

problem of weighment is alleviated by direct mounting the hoppers over the boilers on

calibrated load cells.

Advantages and disadvantages of direct method

Advantages:

It is very simple and quick method for boiler efficiency evaluation and plant person can

easily evaluate the efficiency on daily basis.

It requires very few parameters to find out boiler efficiency and calculation is also very

simple.

It requires only few instruments for monitoring.

It gives a fair idea of boiler efficiency

Disadvantages:

It does not shows the reason for low efficiency

It does not calculate various losses which are accountable for various efficiency levels.



13.6 Indirect method

Indirect method is also called as “heat loss” method. The efficiency of boiler can be arrived

at by subtracting various heat loss fractions from 100.

The standard do not include blow down loss in the efficiency determination process.

Fig. 2 Heat balance diagram by indirect method

Main losses which occurs in the boiler are tabulated below

Sl. No Types of losses

1 Loss of heat due to dry flue gas

2 Loss of heat due to moisture in fuel

3 Loss of heat due to moisture in combustion air

4 Loss of heat due to combustion of hydrogen

5 Loss of heat due to radiation

6 Loss of heat due to unburnt

Table No 1

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In the above, loss due to moisture (Sl.no 2) in fuel and loss due to combustion of hydrogen

(Sl.no 4) are dependent on the fuel

Losses (Sl.no 2 and 4) can not be controlled by the boiler design.

Data required for evaluation of boiler efficiency using direct method as tabulated below

Sl. No Description

1 Ultimate analysis of coal

2 Percentage of oxygen or CO2 in the flue gas

3 Flue gas temperature in OC ( Tf)

4 Ambient temperature in OC (Ta)

5 Humidity of air in kg/kg of dry air

6 Gross calorific value of fuel( coal) in kCal/kg

7 Percentage combustible in ash ( in case of solid fuel like coal)

8 Gross calorific value of ash in kCal/kg (in case of solid fuel like coal)

Procedure for boiler efficiency evaluation:

First of all we have to calculate the amount of theoretical air requirement for the combustion

of fuel

This may be calculated by following equation:

Theoretical air requirement

= [(11.6 x C) + {34.8 X ( H2

- O2/8)} + ( 4.35 x S )] /100 kg/kg of fuel

Where,

C = carbon %

H = Hydrogen %

0 = Oxygen %

S = Sulphur %

Excess Air supplied (EA) can be calculated as:



EA = 02 %/( 21-O2 %) x 100

Actual mass of air supplied/ kg of fuel (AAS) = {1+ EA/100} x Theoretical air Calculation of

various losses as shown in table no 2

1. Percentage heat loss due to dry flue gas

= {m x Cp x ( T

f-T

a) x 100 } / GCV of fuel

Where,

m = mass of dry flue gas in kg/kg of fuel

m = combustion products from fuel: CO2 + SO2 + nitrogen in fuel + Nitrogen in the

actual mass of air supplied + O2 in flue gas. ( H2O / water vapour in the flue gas

should not be considered.

Cp = Specific heat of flue gas ( 0.23 kCal/kg OC)

Tf

=

Flue gas temperature in OC

Ta = Ambient temperature in OC

GCV = Gross calorific value of fuel

2. Percentage heat loss due to evaporation of water formed due to H2 in Fuel

= [9 x H2 x {584 + Cp ( Tf-Ta)} / GCV of fuel] x 100

Where,

H2 = kg of hydrogen in 1 kg of fuel

Cp

= Specific heat of superheated steam ( 0.45 kCal/kg OC)

3. Percentage heat loss due to evaporation of moisture present in fuel

= [ M x {584 + Cp ( T

f-T

a)} / GCV of fuel] x 100

Where,

M = kg of moisture in 1 kg of fuel

Cp


584 is the latent heat corresponding to the partial pressure of water vapour

4. Percentage heat loss due to moisture present in air

= {AAS x humidity factor x Cp ( T

f-T

a) / GCV of fuel} x 100



Where,

Cp


5. Percentage heat loss due to unburnt in fly ash

= {(Total ash collected per kg of fuel burnt x GCV of fly ash) / GCV of fuel} x 100

6. Percentage heat loss due to unburnt in bottom ash

= {(Total ash collected per kg of fuel burnt x GCV of bottom ash)/ GCV of fuel} x 100

7. Percentage heat loss due to radiation and unaccounted loss

The other heat losses from a boiler consist of the loss of heat by radiation and convection

from the boiler into the surrounding boiler house.

Normally surface loss and other unaccounted losses are assumed based on the type and

size of the boiler as given below:

For Industrial fire tube boiler/ packaged boiler = 1.5 to 2 %

For Industrial water tube boiler = 2 to 3 %

For power plant boilers = 0.4 to 1%



Heat Balance :

After calculation of various losses mentioned above, a simple heat balance would give

the efficiency of boiler.

The efficiency is the difference between the energy input to the boiler and the heat losses

calculated.

Boiler heat balance:

Input/output parameter kCal/ kg of fuel %

Heat input in fuel = 100

Various heat losses in boiler

1. Loss of heat in dry flue gas =

2. Loss due to hydrogen in fuel =

3. Loss due to moisture in fuel =

4. Loss due to moisture in air =

5. Loss due to unburnt in fly ash =

6. Loss due to unburnt in bottom ash =

7. heat loss due to radiation and unaccounted loss =

Total losses =

Efficiency of Boiler (ç) = 100-(1+2+3+4+5+6+7)



14. GLOSSARY- COAL

Anthracite

A hard, compact coal characterized by high luster and low sulphur content. Anthracite is comprised

of less volatile matter than bituminous coal, which provides for its nearly non-luminous flame, with

highest carbon content (86% to 98%) and thus highest heat value (nearly 15,000 BTUs-per-pound);

Bituminous

Type of coal with carbon content from 45% to 86% and heat value of 10,500 to 15,500 BTUs-per-

pound; used primarily to generate electricity and make coke for steel.

Bitumen

A hard, black, combustible substance formed from decomposed vegetable matter subjected to

pressure, temperature, and moisture for millions of years. Varying conditions of formation result in

diverse coal chemistries and heat contents. Bituminous coal is one of several phases in an evolutionary

development process which includes (from least developed to most developed): peat, lignite

(sometimes called brown coal), sub bituminous, bituminous, anthracite (sometimes called hard coal)

and graphite. A mixture containing hydrocarbons — often produced by the processing of coal or oil

— used in asphalt or tar for road surfacing or waterproofing.

Coke

A hard, dry substance containing carbon that’s produced by heating bituminous coal to a very high

temperature in the absence of air

Lignite

Type of coal with lowest carbon content (25% to 35%) and a heat value of only 4,000 to 8,300

BTUs-per-pound; called “brown coal;” used mainly for electric power generation.

Peat

partially carbonized vegetable material.



Sub bituminous

Type of coal with 35% to 45% carbon content and heat value of 8,300 to 13,000 BTUs-per-pound;

generally has lower sulfur content than other types, and so is cleaner-burning.

Ash

The non-combustible and inorganic component of coal remaining after complete burning. Ash yields

no heating value.

Ash Fusion Temperatures

a. Initial Deformation Temperature

Temperature at which the top of the ash cone begins to round.

b. Softening Temperature

Temperature at which the ash cone fuses into a spherical lump.

c. Fluid Temperature

Temperature at which the ash cone spreads out over the base as a flat layer.

2,600 degrees F – A high ash fusion temperature.

2,100 degrees F – The lowest approximate ash fusion temperature of coals.

1,950 degrees F – The ash fusion temperature of several coals.

1,850 degrees F – The approximate ash fusion temperature of coals.

ASTM

American Society for Testing and Materials. The ASTM provides a system for classifying coal as

well as other testing parameters..

BTU

British thermal unit the amount of heat required to raise the temperature of one pound of water one

degree Fahrenheit under normal conditions.



BTU (as received)

indicates the heating value of coal at the location of consumption.

BTU (dry basis)

The method of fuel analysis where the moisture is eliminated and the other constituents are

recalculated to total 100 percent.

Clean Coal Technology

Because of environmental pollution concerns from the burning of coal, increased efforts are being

made to develop better emission control or reduction technologies. These technologies apply to

cleaning impurities from the coal itself, improving the effectiveness of the burning process, and/or

improving the pollutant recovery systems for the escaping products of combustion.

Coke (coal)

In general, coke is made from bituminous coal (or blends of bituminous coal) from which the volatile

constituents are driven off by baking in an oven at temperatures as high as 2,000 degrees Fahrenheit,

so that the fixed carbon and ash are fused together. Coke is hard and porous and has a gray, sub-

metallic luster. It is used both as a fuel and for chemical reactions in smelting iron ore in a blast

furnace in making pig iron and steel. Coke has a heating value of 13,000 to 14,000 BTU/pound.

Dried Coal

Moisture, an inherent component of coal, requires heat for its evaporation and release in the products

of combustion. Surface moisture in cold climates increases handling problems. Normal atmospheric

drying of coal is accelerated by passing hot combustion gases over or through beds of coal to be

dried (usually metallurgical coal).

Grindability Index

Indicates the ease of pulverizing a coal in comparison to a reference coal. This index is helpful in

estimating mill capacity. The two most common methods for determining this index are the Hard

grove Grindability Method and Ball Mill Grindability Method. Coals with a low index are more

difficult to pulverize. On a one to 100 scale, the lower the value the harder the coal.



Megawatt (MW)

A watt is a unit of electric power; the output capability of electric generating plants, companies and

systems is usually expressed in terms of megawatts (millions of watts). One watt = 3.4 BTU/hr. One

kilowatt = 1.3 horsepower..

Proximate Analysis

A percentage measurement of the physical properties of coal including moisture, volatile matter,

fixed carbon and ash. Proximate analysis is usually accompanied by a statement of sulphur content,

BTUs per pound, ash fusion temperature and grindability, expressed in percentages by weight.

Sulphur

A non-metallic chemical element comprising varying degrees of coal’s composition. Sulphur burns

off when coal is heated but promotes clinkering, slagging and corrosion. Coals with high sulphur

contents are susceptible to spontaneous combustion in storage piles. Sulphur present in stack emissions

is regulated by clean air standards.

Sulphur Classifications

Pyritic

The only inherent form of sulphur in coal which can be removed by washing.

Organic

Inherent and generally cannot be removed from coal.

Sulphates

Oxidation products, present on the surface of fresh coal in small amounts. Sulphates can be

removed conveniently through standard cleaning processes.

Ultimate Analysis

Chemical properties of coal represented in percentage of weight. Included are carbon, hydrogen,

sulphur, oxygen and nitrogen.



Volatile Matter

Portion of coal which is driven off in a gaseous form when the coal is heated. Volatility is classified

as follows:

Composition by Weight

high volatile over 31%

medium volatile 22% to 31%

low volatile under 22%

Fixed carbon — The solid combustible residue left after the moisture and volatile matter have been

driven off by heating. In the proximate analysis, it is calculated by subtracting the sum of moisture,

ash and volatile matter from 100 percent.

Fly ash — The fine particles of ash that are carried through the various passes in the furnace by the

products of combustion and are usually collected in the last pass of boiler by a precipitator or dust

collector.

Moisture —

Free moisture (or surface moisture) — The portion of total moisture that comes from external

sources such as rain or snow.

Inherent moisture (or bed moisture) — Moisture that exists as an integral part of the coal

seam prior to mining.

Total moisture — Moisture that is determined as the loss in weight of a coal sample in an air

atmosphere under rigidly controlled conditions of time, temperature and air flow. . . .

Rank — A classification of coal that indicates the degree of coalification or alteration from lignite

to anthracite.

Spontaneous combustion — An ignition caused by the accumulation of heat generated by the slow

oxidation of coal in an air supply sufficient to support oxidation but insufficient to dissipate the

heat. An example of where this can occur is a storage pile. The tendency of a coal to spontaneously

combust or self-heat increases with increasing amounts of sulfur and moisture.



ANNEXURE -1

TECHNOLOGICAL DEVELOPMENT INCOAL TESTING EQUIPMENTS



Indi

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May

June

July

Aug

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Sept

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Oct

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Nov

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Dec

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STANDARD OPERATING PROCEDUREON

COAL LOSS ACCOUNTINGQUANTITATIVE(Mine To Factory)

MANAGEMENT SERVICES DIVISIONMarch 2007

1. Overview of Coal Mining ......................................................................................................... 89

2. Handling of Coal at Mines ........................................................................................................ 91

3. Loading of Coal on Truck or Rake At Mines ........................................................................ 96

4. Loading or Discharge of Coal from Vessel ............................................................................. 102

5. Transit of Coal ............................................................................................................................ 108

6. Stock Verification ........................................................................................................................ 110

Annexure – 1: Risk Assessment Procedure ............................................................................ 113

SOP-COAL LOSS ACCOUNTING : QUANTITATIVEMINE TO FACTORY

TABLE OF CONTENTS

SOP-Coal Loss Accounting: Quantitative, (Mine to Factory)

Management Services Division 89

1. OVERVIEW OF COAL MINING

The choice of mining method is largely determined by the geology of the coal deposit. Underground mining

currently accounts for about 60% of world coal production, although in several important coal producing

countries surface mining is more common.

1.1 UNDERGROUND MINING

There are two main methods of underground mining: ‘room & pillar’ and longwall mining.

In room-&-pillar mining, coal deposits are mined by cutting a network of ‘rooms’ into the coal seam

and leaving behind ‘pillars’ of coal to support the roof of the mine. These pillars can be up to 40% of

the total coal in the seam – although this coal can sometimes be recovered at a later stage. This can

be achieved in what is known as ‘retreat mining’, where coal is mined from the pillars as workers

retreat. The roof is then allowed to collapse and the mine is abandoned.

Longwall mining involves the full extraction of coal from a section of the seam or face’ using mechanical

shearers. A longwall face requires careful planning to ensure favourable geology exists throughout the

section before development work begins. The coal ‘face’ can vary in length from 100-350m. Self

advancing, hydraulically-powered supports temporarily hold up the roof while coal is extracted.

When coal has been extracted from the area, the roof is allowed to collapse. Over 75% of the coal

in the deposit can be extracted from panels of coal that can extend 3km through the coal seam.

The main advantage of room–&-pillar mining over longwall mining is that it allows coal production to

start much more quickly, using mobile machinery that costs under $5 million (longwall mining machinery

can cost $50 million).

The choice of mining technique is site specific but always-based on economic considerations;

differences even within a single mine can lead to both methods being used.

1.2 SURFACE MINING

Surface mining – also known as opencast or open-cut mining – is only economic when the coal seam

is near the surface. This method recovers a higher proportion of the coal deposit than underground

mining as all coal seams are exploited – 90% or more of the coal can be recovered.


Management Services Division90

The productivity per man-shift in open cast mining is more than 5 times that in underground mining.

Large opencast mines can cover an area of many square kilometers and use very large pieces of

equipment, including:

draglines, which remove the overburden;

power shovels; large trucks, which transport overburden and coal;

bucket wheel excavators, and

conveyors.

Explosives first break up the overburden of soil and rock; it is then removed by draglines or by

shovel and truck. Once the coal seam is exposed, it is drilled, fractured and systematically mined in

strips. The coal is then loaded on to large trucks or conveyors for transport to either the coal prepa-

ration plant or direct to where it will be used.



2. HANDLING OF COAL AT MINES

2.1 COAL PREPARATION

The raw coal produced from the mine (run-of-mine or ROM) hardly suits the need of the consumers.

It is necessary to exercise control over one or more of its properties like size (mainly) depending

upon the nature of its use.

Coal straight from the ground, known as run-of-mine (ROM) coal, often contains unwanted impuri-

ties such as rock and dirt and comes in a mixture of different-sized fragments.

However, coal users need coal of a consistent quality. Coal preparation – also known as coal

beneficiation or coal washing – refers to the treatment of ROM coal to ensure a consistent quality

and to enhance its suitability for particular end-uses.

The treatment depends on the properties of the coal and its intended use. It may require only simple

crushing or it may need to go through a complex treatment process to reduce impurities.

To remove impurities, the raw run-of-mine coal is crushed and then separated into various size

fractions. ROM coal usually has a size of 0-500mm. The sized coals may be available in various

ranges, such as steam sized coal : 250-25mm, rubble: 50-25mm, smithy: 25-13mm, and slacks: 50-

0mm, 25-0mm, and 13-0 mm. The screening of coal is done on various types of screens, revolving,

vibrating and shaking. Larger material is usually treated using ‘dense medium separation’. In this

process, the coal is separated from other impurities by being floated in a tank containing a liquid of

specific gravity, usually a suspension of finely ground magnetite. As the coal is lighter, it floats and can

be separated off, while heavier rock and other impurities sink and are removed as waste.

The smaller size fractions are treated in a number of ways, usually based on differences in mass, such

as in centrifuges. A centrifuge is a machine, which turns a container around very quickly, causing

solids and liquids inside it to separate. Alternative methods use the different surface properties of

coal and waste. In ‘froth flotation’, coal particles are removed in a froth produced by blowing air into

a water bath containing chemical reagents. The bubbles attract the coal but not the waste and are

skimmed off to recover the coal fines. Recent technological developments have helped increase the

recovery of ultra fine coal material.

2.2 COAL HANDLING

The loading and unloading of trucks and railroad cars can generate large amounts of dust. Basically

dust percentage depends on the size of coal also. This is major coal loss point at mines sector also.

During transportation, fine dust is lost to relative (head) wind.



2.3 COAL TRANSPORTATION

The way that coal is transported to where it will be used depends on the distance to be covered.

Coal is generally transported by conveyor, ropeway or truck over short distances. Trains and barges

are used for longer distances usually within domestic markets.

Ships are commonly used for international transportation, in sizes ranging from Handymax (40-

60,000 DWT), Panamax (about 60-80,000 DWT) to large Capesize vessels (about 80,000+ DWT).

(DWT – Deadweight Tonnes which refers to the deadweight capacity of a ship, including its cargo,

bunker fuel, fresh water, stores etc).

Around 725 million tonnes (Mt) of coal was traded internationally in 2005 and around 90% of this

was sea-borne trade. Coal transportation can be very expensive – in some instances it accounts for

up to 70% of the delivered cost of coal. So measures are taken at every stage of coal transportation

and storage.

Technological Characteristic of Rolling stock and Railway Transport

The cars used in pits have an open body to permit excavator loading and mechanical or manual

emptying. They must withstand large impact loads, ensure rapid emptying and possess a higher

stability. Self-emptying dumpers have found the widest application in this loading process and most

of the dumpers with hinged sides of a capacity 180 MT approximately.

The body capacity of a wagon “q” is the maximum amount of load (in MT) admissible by the design

strength of the wagon. Wagon volume ‘Vc’ corresponds to the geometrical volume of the body. The

summary body capacity of the wagon of a rake is referred to as the useful mass of the rake. Strength

and loading conditions require that the volume of a dumper should be 4-6 times greater than the

volume of excavator bucket. The mass of individual lumps must not exceed 3-3.5 MT at a dumping

height (emptying) height, measured from the car bottom, hdm

= 2-2.5 m and 5-6MT at hdm

£0.5 m.

When the material is loaded with rail-mounted bucket-chain excavators, the specific volume of wagon

(per meter length) must be in line with the output and moving speed of the excavators.

In this regards railway track layout and design of division points is also very important

The track layout of a quarry depends on its production and surface dimensions of the pit, the intensity

of freight traffic, the kind of wagon/ rake, opening diagram, mining methods etc. The track layout of

a quarry includes:



a) Temporary tracks laid at faces and waste disposal areas; these tracks are shifted periodically

as the mining, stripping and waste dump benches advance;

b) Connecting tracks linking the face and waste-dump ways with the tracks laid in the main

trenches and on the surface, with the stations and other departments of the enterprise;

c) Track laid the main trenches and access track (ramps) connecting the operating levels of a pit

with surface tracks;

d) Division points ensuring safe and efficient train movement in a pit and on the surface.

Technological Characteristic of Rolling stock and Haulage Vehicle

Quarries and pits mostly favour rear-dump trucks over other existing kinds of motor vehicles.

The type of engine, transmission, running gear, steering and the truck body tipping gear are chosen

based on the capacity of the motor vehicles. Normally dump trucks powered by carburetor engines

of up to 5 –t capacity are used for hauling soft rocks (when they are loaded by excavators with a

bucket capacity up to 1 m3), dimension stone, and also for hauling supplies, materials, equipment,

etc. Similar excavators are also served by diesel-powered dump trucks of 5-7 MT capacities. Me-

dium (10-20 MT) and heavy-duty (over 20 MT) diesel-powered dump trucks find wide application

in quarry haulge.

Truck Positioning in Faces and at Waste Dumps

The various types of face and cut, the different width of the cuts, the nature of truck movement on

benches (one-way or opposing movement), the relationship between the directions of motion of the

trucks and excavator, and the high mobility of trucks make it possible to position them for loading in

a great number of ways.

Trucks may move on the bench in the direction of the excavator, which carries a cut, or in the

opposite direction. The manner in which the trucks approach the excavator subdivides the way in

which trucks are positioned for loading into 3 groups: straight past, with a loop turn, with a dead-end

turn. The mine rock must be loaded into the truck body from the side or rear; the bucket must not be

carried on top of the cab. Empty (idle) trucks must be positioned outside the radius of action of the

bucket.



With an end face in through cut and one-way truck movement (two transport exist on a bench),

trucks are positioned as shown in Figure below. For positioning movement straight past (1,3,9)

pattern is utilized, for one-way traffic loop turn (2,10) or dead-end (12,14) patterns are applied

(with face grading or large yield of oversize lumps). With opposing truck movement they are posi-

tioned for loading as illustrated in Fig. (loop turn patterns 19,20 (wide operating beams) and dead-

end patterns 23,24 (narrow beam)). With one-way movement turning around of empty dump trucks

is preferable (20, 24). With wide through cuts similar loop turn patterns 27, 28 and also the dead-

end pattern 30 are followed.

In dead-end production cuts, trucks are usually positioned for loading according to pattern 24, and

sometimes 26; in wide dead-end trench cuts, trucks are positioned according to patterns 33 and 34.

With frontal faces, selective mining usually requires that trucks be positioned for loading according to

dead-end patterns 17, 18, 38, and loop turn 36.

Type

of

Face

Lon

gitu

-d

inal

End

Fac

e

Thr

ough

Dea

d-en

d tr

ench

Thr

ough

dead

-end

Thr

ough

Thr

ough

Type

of c

ut

Cut with

Normal An

≈ ≈ ≈ ≈ ≈ (1.5 –1.7) R

dn

Normal andnarrow An ≈≈≈≈≈

0.5Rdn

WideA

w>>>>>2R

dn

Sufficientfor loop

turning A ≥2 (Rmn+ m)

Insufficientfor loop

turning A <2 (Rmn+ m)

Narrow

Specialmining

conditions

Wideworking

bems

MinimumWidth ofworking

bems

Withoutface

grading

With facegrading

Truck movement on bench and schematics of truck positioning for loading

One-way Opposing

Through and loop dead-end loop dead-end

Direction of excavator and empty truck movement

Opposing One-way Opposing One-way Opposing One-way Opposing One-way

Ch, 16. T

ruck Haulage

Figure: Spotting dump trucks for loading

Rmin — minimum truck turning radius; m — clearance between truck and trench slope



FLOW CHART

Flow Activity Responsibility Unit Control Remarks

Mining of coal Coal India Nil

Coal Handling plant Coal India Liaison with

respective person

Storage at Bunker Coal India Liaison with respective

person to know the

stock quantity

Loading through Auto Loader Coal India Liaison with respective

person for good loading

Loading Supervision Co –ordinate with

Coal India’s Staff Mainly Mine manager,

Field In-charges are

important

Triming, Marking and Leveling Maintain the good level

with more than 1 ft height

from wagon in

Trapezoid profile.

Weighment Supervision Coal India Check the process and

liaison with respective

person Check point:

Calibration



3. LOADING OF COAL ON TRUCK OR RAKE AT MINES

3.1 Administration

3.1.1 Check job instructions like

a) Loading commenced

b) Exact Location

c) Number of Dumpers present

d) Quantity

e) Customer

f) Total Time of Loading

3.1.2 In case of Coal India, submit the requisition in head office of Coal India on 1st date of every

month and care should be taken to forward the same into the respective regional office of

Coal India.

3.1.3 Confirm receipt of instructions with Authorised person. Authorised person should take care

and liaison with Coal India and Railways regarding the placement of rake so that the material

can be loaded within 20th of every month.

3.1.4 Always check the stock at the bunker and try to load the material when production rate is

high.

3.1.5 What is the nature of the material and what facilities are available - size of coal, sampling lot

size, handling conditions, and preparation facilities?

3.1.6 Is a ‘Permit to Work’ required and/or local induction? For local permit contact with the

colliery manager.

3.1.7 Are sufficient inspectors available to cover all eventualities of the operation?

No – immediately contact with Authorised Person. It is the responsibility of the inspec-

tor to ensure that the office is fully aware of the situation so that adequate infrastructure

can be provided.



3.2 Health & Safety

3.2.1 Is there a risk assessment for the nominated location and material?

Yes – Ensure required personal protective equipment (PPE) and risk management prac-

tices in place before starting work.

No - carry out risk assessment with Field Services Technical Coordinator and docu-

ment risk management procedures.

3.3 Pre-Loading Planning

3..3.1 Establish the loading plan with material handling agent or transporter.

Material in one or more stockpile?

Multi stockpile discharge?

Online discharge?

Anticipated hours of working.

Availability of the enough space for truck movement.

3..3.2 Is volumetric assessment required?

Yes – Ensure that the two volumetric assessments furnished. One completed from stockpile

prior to loading and another completed after loading.

3.4 Rake or Truck Inspection

3.4.1 Collect and record the relevant dates/times of rake placement or truck position.

3.4.2 Depute the adequate inspectors.

3.4.3 The following parameters of all the trucks/ wagons shall be checked properly.

Fitness.

Condition.



Rust free.

Dust free.

Visual identification.

Crack free and good condition.

3.4.4 Foreign Matter: The wagon/ truck should be free from any types of foreign material. The

following shall be considered as the foreign materials:

Any chemicals other than loading materials.

Rust.

Lumpy dust (stone etc.).

Grease.

Oil.

Welding residuals.

3.5 Coal Inspection

3.5.1 Confirm stockpile/ running of material and loading with the authorized person of mines.

3.6 Loading

3.6.1 Inspect the wagon from a safe location regularly during loading. The number of visits re-

quired will depend on the nature of the coal and the loading conditions. As a minimum the

wagon should be checked 2 or 3 times per shift and at any time when the coal visibly

changes.

3.6.2 Describe weather conditions during discharge and possible effects on moisture content of

coal.

3.6.3 Note the times and any changes in material appearance, water ingress, especially when

loading start.



3.6.4 Report on loading procedure,

3.6.5 Crane, grab type and approximately lifting capacity.

3.6.6 Were wagon or truck loading simultaneously or individually?

3.6.7 Was coal placed into integrated or independent hoppers?

Did hopper feed for road transport or a conveyer belt system

3.6.8 Or was coal placed directly on to the quay?

How was it picked up and delivered to storage?

3.6.9 Was the equipment and quay clean prior to loading?

3.6.10 Was “Grabbing” within the wagon or rake aided by pay-loader at any time?

3.6.11 Describe the condition of the quay at completion of loading.

3.6.12 Were quay and plot sweepings recovered?

Yes - into a separate lot or during loading?

If sweepings were not recovered estimate the amount of material lost and immediately

inform to the authorized person and request recovery of sweepings.

3.7 Weighing

3.7.1 Was coal weighed by weighbridge, belt weigher or hopper load cell?

3.7.2 Describe scales, weighing capacity and weighing divisions

3.7.3 Prior to loading was the weighing equipment calibrated and tested by an independent certi-

fication authority and valid certificates sighted?

3.7.4 No – Request alternative, certified weighing equipment be made available immediately.



3.7.5 Test equipment with calibrated, stamped or known weights?

3.7.6 If weighing equipment fails calibration check request adjustment and re-test until scales OK.

3.7.7 Was the coal transported prior to weighing?

3.7.8 By road?

Was coal covered, tailgates securely closed, and any spillages?

When and how often were the vehicles tare weighed?

3.7.9 By conveyor belt - any spillages or losses at belt cross-over points or elsewhere?

3.7.10 By hopper - can the pit and the hopper tops be sighted for signs of leakage or seepage of

coal?

3.7.11 Was the loading quantity assessed by only weighment or volumetric assessment?

3.7.12 By volumetric assessment?

Was the bulk density of coal determined at for 10 readings?

Was the surface of the coal loaded plain or symmetric?

Was the dimensional measurement done by instrument or manual?

Has the quantity surveyor adequate training and experience of handling the instruments

or manual measurement.



coal?

3.7.15 If significant spillage or losses are observed bring them to the attention of responsible person

on site to recover lost material. If no satisfactory response, estimate amount of material lost,

inform authorised person and follow instructions.



3.8 Transport & Storage

3.8.1 Was coal transported to storage or silos by conveyor belt?

Covered?

Open?

3.8.2 Coal transported by covered/open by rake or by road?

Distance.

Condition of storage facility covered or open, floor area.

Other material stored nearby [contamination]

Security



4. LOADING OR DISCHARGE OF COAL FROM VESSEL

4.1 Administration

4.1.1 Check job instructions

4.1.2 Confirm receipt of instructions with Authorised person.

4.1.3 What is the nature of coal and what facilities are available:- size of coal, sampling lot size,

handling conditions, preparation facilities?

4.1.4 Is a ‘Permit to Work’ required and/or local induction?

4.1.5 Are sufficient inspectors available to cover all eventualities of the operation?

No – immediately contact Field Services Coordination Team Leader. It is the respon-

sibility of the inspector to ensure that the office is fully aware of the situation so that

adequate cover is provided.

4.2 Health & Safety

4.2.1 Is there a risk assessment for the nominated location and material?

Yes – Ensure required personal protective equipment (PPE) and risk management prac-

tices in place before starting work.

No - carry out risk assessment with Field Services Technical Coordinator and docu-

ment risk management procedures.

4.3 Pre-Discharge/ Loading Planning

4.3.1 Establish the discharge/loading plan with stevedore and/or ship’s agent.

Material in one or more holds?

Multi hold discharge?

Sequence of discharge from holds



Anticipated hours of working

Availability of unloading labour / Gang

Discharge using ship’s crane or shore crane?

Grab type and lifting capacity?

4.3.2 Is draft survey required?

Yes – Ensure survey completed prior to discharge.

4.4 Vessel Inspection

4.4.1 Present yourself to Chief Officer and/or Captain.

4.4.2 Record relevant ships dates/times.

4.4.3 Record “comments made by vessel” – e.g. load port dates, loading and weather conditions,

weather on voyage, bilges pumped (ensure reports states “comments made by vessel”)

4.5 Coal Inspection

4.5.1 Confirm stowage of material and discharge plan with Chief Officer.

4.5.2 Report type of hatch covers and apparent condition, particularly on underside (i.e. obvious

rust?)

4.5.3 Report condition of hatch/hold:- any damage or significant rust?

4.5.4 Report coal condition when hatches opened.

Was the coal steaming?

Any condensation on underside of hatch covers?

Any visible water inside hatches?

4.5.5 Observe coal in the hold (from the deck) and record relevant observations.



Are lighting conditions adequate to view cargo?

Was the cargo in a peaked or a trimmed condition?

Any indications of travel cracks, oxidation, water staining, free water, visible contami-

nation?

4.5.6 Was the material uniform in colour, fines or fines with agglomerates? (If so to what approxi-

mate percent and size?).

4.6 Discharge

4.6.1 Inspect the hold from a safe location regularly during discharge. The number of visits re-

quired will depend on the nature of the coal condition and the discharge conditions. As a

minimum the hold should be checked 2 or 3 times per shift and at any time when the coal

visibly changes.

4.6.2 Describe weather conditions during discharge and possible effects on moisture content of

coal.

4.6.3 Note times and any changes in material appearance, water ingress, especially when dis-

charge is reaching bottom of the hold.

4.6.4 Report on discharge procedure,

Crane, grab type and approximately lifting capacity.

Were holds discharging simultaneously or individually?

4.6.5 Discharge rate per hour, measure cycle time – does it meet assured levels?

4.6.6 Was coal placed into integrated or independent hoppers?

Did hopper feed road transport or a conveyer belt system

4.6.7 Or was coal placed directly on to the quay?

How was it picked up and delivered to storage?



4.6.8 Were “Save-alls” fitted between vessel and quay or deflector plates fitted to cranes?

4.6.9 Was the equipment and quay clean prior to discharge?

4.6.10 Was “Grabbing” within the hold aided by pay-loader at any time?

4.6.11 Was the hold cleaned at completion of discharge?

4.6.12 Describe the condition of the quay at completion of discharge.

4.6.13 Were quay and hold sweepings recovered?

Yes - into a separate lot or during discharge?

If sweepings were not recovered estimate the amount of material lost and immediately

inform stevedore, ship’s agent and request recovery of sweepings. If no action immedi-

ately inform authorised person.

4.7 Weighing

4.7.1 Was shipment weighed by draft survey?

Yes – obtain surveyor’s initial, interim and final reports.

4.7.2 Assess the conditions of the port for draft surveys, i.e. calm water, good visibility?

4.7.3 Was coal weighed by weighbridge, belt weigher or hopper load cell?

Describe scales, weighing capacity and weighing divisions

4.7.4 Prior to discharge was the weighing equipment calibrated and tested by an independent

certification authority and valid certificates sighted?

No – Request alternative, certified weighing equipment be made available immediately.

If request refused immediately advise Client Account Coordinator and follow

instructions.

4.7.5 Test equipment with calibrated, stamped or known weights?



If weighing equipment fails calibration check request adjustment and re-test until scales

ok.

4.7.6 Was coal transported prior to weighing?

By road?

Was coal covered, tailgates securely closed, any spillages?

When and how often were the vehicles tare weighed?



material?

4.7.9 If significant spillage or losses are observed bring them to the attention of responsible person

on site to recover lost material. If no satisfactory response, estimate amount of material lost,

inform Client Account Coordinator and follow instructions.

Weights given to Client Account Coordinator as instructed

4.8 Transport & Storage

4.8.1 Was coal transported to storage or silos by conveyor belt?

Covered?

Open?

Was any water sprayed during transportation?

4.8.2 Coal transported to storage by covered/open conveyor belt or by road?

Distance from vessel to storage area.

Condition of storage facility covered or open, floor area.

Other material stored nearby [contamination]

Security



4.9 Other

4.9.1 Record weather conditions during discharge and sampling.

4.9.2 Record any stoppages and reasons for stoppage.

4.9.3 Record any other relevant information.

4.9.4 Complete report and forward to authorised person.



5. TRANSIT OF COAL

5.1 Security Procedure in Transit

5.1.1 Was coal transported by rake with security guard?

Number of security?

- Generally minimum 6 numbers securities are required in which 3 will be armed (gun).

Gunman or simple person?

- At least 3 gunman are required.

5.1.2 Was critical theft zone during transportation identified?

Place with probability of theft.

Appointment of local security guard.

Surface marking of the cargo on wagon or truck.

5.1.3 Was coal transported by rake or truck sealed ?

Integrity of the sealing agency.

Checking arrangement of seal at different location.

5.2 Other

5.2.1 Record weather conditions during discharge and sampling.

5.2.2 Record any stoppages and reasons for stoppage.

5.2.3 Record any other relevant information.

5.2.4 Complete report and forward to authorised person/agency.



5.3 Assessment

The assessment shall include:

5.3.1 Identification and evaluation of critical infrastructures.

5.3.2 Identification of threats to those infrastructures including material

5.3.3 Identification of security weakness in coal movement, transportation infrastructure,

protection systems, communication system.

5.3.4 Identification of proper trapezoid loading profile, trimming and marking

5.3.5 Identification of suitable cover by using tarpolins or similar material.

5.4 Recommendation to reduce transit losses

5.4.1 Deploy the security guard with gun man

5.4.2 Improve the security in theft prone zone and implement the local security.

5.4.3 Conduct public campaigns at theft prone zone

5.4.4 Load the material in a systematic manner and trim the upper part to identify the theft mark

5.4.5 Cover the wagon and seal it, if possible

5.4.6 Check the online weighment system to avoid loss.

5.4.7 Deploy private agency for security purpose, if losses are significantly high.



6. STOCK VERIFICATION

6.1 Introduction

6.1.1 Coal stock can be determined by measuring the volume of the coal yard and height of the

stack pile. The following procedure specifies a method for the quantitative assessment of

coal stock in a stack pile.

6.1.2 Team Building is required for stock assessment. The team consists atleast one from pur-

chase or commercial side, one from user side i.e. from plant side and another from adminis-

trative side. Depending on situation independent third party can also be deputed. Stock

verification should be carried out atleast once in every quarter.

6.2 Procedure

6.2.1 Normally stack of coal are in irregular shapes, i.e. they are not in proper geometrical shapes.

In order to get better assessment of the stacks, the stacks are subdivided longitudinally into

several subdivisions.

Divide the whole plot into 20 or more imaginary subdivisions. Measure the length and

breadth of the each subdivision.

Measure the common height of the stack. Then take the adequate measurements of

uneven height of each subdivision. Calculate the average height of each subdivision by

using steel tape or theodolite.

Calculate the volume of each subdivision by multiplying area with average height.

Collect the coal from each subdivision and measure the bulk density and moisture as

per procedure given below.

6.2.2 Procedure of Measuring the Bulk Density

Principle

A weighed container of known volume is filled with coal and the increase in mass is

determined.



Apparatus

a) Cubical Container of capacity 0.200m3 and internal dimension 585mm, with a smooth

inner surface, rigidly constructed and fitted with handle.

b) Weighing machine, Spring Balance or Platform balance with accuracy 50 gms.

Procedure

Place the container on the weighing machine and record its mass. Charge the coal

slowly into the container until pieces of coal project above the top of the container

across the whole surface. The height of drop of the coal shall not exceed 250 mm.

Slide a straight edge across the top of the container and remove any pieces of coal,

which obstruct its passage. Weigh the charged container.

Calculation

The bulk density in a small container (rs) of the coal, in Kg per m3, on dry basis is given

by the equation:

( ) ( ) ( )s 2 1ρ = m -m × 100-M / 100V

Where,

m1 is the mass in kg, of the empty container;

m2 is the mass in kg, of the container plus coal;

V is the inner volume in m3, of the container;

M is the total moisture content of the coal determined in accordance with ISO 589.

6.2.3 Calculation for Quantity Assessment

Measure the Height of the subdivision by using steel tape or theodolite and take the

average of these height of each subdivision.



Average Height of Each Subdivision,

h1

is the depth in m, of the 1st hole;

n is the number of holes.

The Volume of each Subdivision,

where,

L1

is the length in m, of the 1st subdivision;

B1

is the breadth in m, of the 1st subdivision;

H1

is the depth in m, of the 1st subdivision;

The Quantity of Coal of 1st Subdivision, W1 = V

1 X B.D

1

where,

B.D is the Bulk Density in MT/m, of the coal

Total Quantity of the stock



ANNEXURE – 1

Procedure for Risk Assessment

The aim of risk assessment is to reduce the risks caused by work and to eliminate, or minimize, injuries and

damage to people and property.

The principals of risk assessment are fourfold and really only embody common sense principles.

They are:

a) Identify the hazards What could happen?

b) Evaluate the risks posed by that hazard Could it happen?

What is the impact?

c) Control those risks Eliminate the hazard or create a

safe system of work?

d) Monitor the controls and measures taken Review and record

A management decision must be made on how to control the risks which have been assessed and evalu-

ated. The priority of the work done to control them and the level of this control will reflect the level of effect

and likelihood of it happening as determined in the evaluation.

It is important to remember that a review of the assessments will be as required if there is a change in the

risk or process.



Two components will be considered once a hazard has been identified. These will be the severity of the

hazards i.e. how bad could it be and the likelihood of occurrence i.e. how likely is it to happen. The grades

of severity and likelihood of occurrence are as follows:

Severity Descriptions

Health Safety Environment

1 Insignificant Normal work can Negligible damage Negligible environmental impactresume after basicfirst aid

2 Minor Lost time injury not Minor damage Minor environmental e.g.reportable to not reportable to localised spillageRegulatory body Regulatory body

3 Moderate Injury/Disease Dangerous/significant Moderate pollution incident (e.g.reportable to damage reportable Contamination of water course)Regulatory body to regulatory body with some restitution costs

4 Serious Fatality/Terminal Substantial property Severe pollution incident with shortDisease/major injury damage term implications with significant

costs

5 Very Serious Multiple/Fatality Catastrophic damage Catastrophic pollutioni.e. process or property incident with longshutdown term implications and

very high costs

Likelihood Description

1. Very Unlikely The Risk may occur in exceptional circumstances

2. Unlikely The Risk is unlikely to occur

3. Possible The Risk will possibly occur

4. Likely The Risk has a significant chance of occurring

5. Very Likely The Risk is almost certain to occur than not



Multiplying the two components together to give a risk factor can then assess the magnitude of the risk.

Low = 1 - 6, Medium = 7 - 14, High = 15 – 25

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NOTES

SOP Coal Loss Accounting Qualitative (Part II)

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Transcript of SOP Coal Loss Accounting Qualitative (Part II)