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Geo-Analyst , ISSN 2249-2909 December, 2015
13
PERFORMANCE ANALYSIS OF DIFFERENT BRICK KILN TECHNOLOGIES
Nazrul Islam* and Dr. Ranjan Roy**
Abstract
Bricks are widely used construction and building materials around the world. . It is a small scale,
traditional industry. The dried bricks were used for the first time in 8000 BC and fired clay bricks
were used as early as 4500 BC. Since the time of inception, brick kiln had followed several
technologies for manufacturing of bricks. The main objective of this paper is to review the
performance of various brick kiln technologies. For this purpose, a detailed literature survey
carried out. Analysis and discussion are done on the basis of energy, environmental, financial and
production and quality of product performance. The paper discusses the performances mentioned
above on the basis of Indian brick kiln sector because India has produced 250 billion bricks
annually from 1,00,000 brick kilns, employing about 15 million workers and consuming about 35
million tons of coal annually. Some key recommendations will be made for the adoption of cleaner
production techniques and for management for better performance in brick productions.
Keywords: Traditional Industry, Kiln technology, Performance, Cleaner production technique,
Biomass fuels.
Introduction
Brick kiln industry is a small scale, a traditional industry which is considered as an unorganized
sector in most of the countries, especially in developing countries. There are three basic needs of
human beings namely Food, Shelter and Clothing which played a significant role in the progress of
human civilisation and all three basic needs gradually improved in their nature as well as variety
directing towards the growth of multidimensional economic activity throughout the world. The
origin of bricks production results from the improvement of shelter of human being in its
quantitative as well as qualitative aspects. Bricks are widely used construction and building
material around the world (Zhang, 2013). The current production of bricks in the world is about
1391 billion units (Freedonia, 2012). India’s annual production of bricks is 250 billion units from
100000 brick factories employing about 15 million skilled and semi-skilled labours and consuming
about 35 million tons of coal annually (Wanjule et.al. 2015). India's share of brick production is
second (17.97%) followed by China (54%). This sector is growing at a faster rate in India (9%
*Assistant Professor, Department of Geography, Sitalkuchi College, Cooch Behar, West Bengal
**Associate Professor, Department of Geography and Applied Geography, University of North
Bengal, Raja Rammohanpur, West Bengal
Geo-Analyst , ISSN 2249-2909 December, 2015
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annually). The brick sector in India consumes about 24 million tons of coal every year. The brick industry is the 3rd largest sector in the consumption of coal (after power and iron and steel
industry) which accounts for 3% of total coal production as well as 1.45 % of total coal
consumption respectively in India. In addition to this, the sizeable amount of bio-mass fuels is
also used in brick kiln industry in different parts of the country. Moreover, it also consumes
several million tons of biomass fuels (eco-bricks, 2017). The cost of energy for brick production is
about 35-40% of total cost of the plant in India.
Objectives
The prime objectives of the present study are as follows -
• To discuss the brief review of brick firing technologies.
• To explore the energy and environmental performance of different types of Brick kilns.
• To estimate the production and productivity performance.
• To suggest some recommendations in favour of improving the performance of brick kiln
technologies.
Materials and Methods
The study has been carried out by reviewing existing literatures such as published and unpublished
research articles, organizational and corporate reports and theses. Relevant websites were also
visited to gather information for fulfilling the objectives. The Government plans, reports were also
reviewed as well. Some secondary data which were monitored by different organizations and
persons individually were also incorporated to assess the performance of the brick kilns. Finally,
the gathered information was tabulated and analyzed to draw a reasonable conclusion.
Results and Discussion
Burning is defined as the union of the principal elements such as coal, carbon, and hydrogen and
with the oxygen of the atmosphere. The dried bricks were used for the first time in 800 BC and
fired clay bricks were used as early as 4500 BC (Pacheco, et. al., 2011). The permanent or semi-
permanent of structures where green bricks are burned is called kiln. The classification of bricks
burning is shown as under-
1. Brick Burning Process
Intermittent Kiln
� Without Stack
Clamp ; Scove ; Scotch
� With Stack
Down Draught Kiln (DDK)
Geo-Analyst , ISSN 2249-2909 December, 2015
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Continuous Kiln
� Moving Fire Kiln
Bull’s Trench Kiln- 1) Moving Chimney Bull’s trench Kiln (MCBTK)
2) Fixed Chimney Bull’s Trench Kiln (FCBTK)
� Hoffman Kiln- 1) Original Hoffman Kiln (OHK)
2) Hybrid Hoffman Kiln (HHK)
� Zig Zag Kiln (ZZK- 1) Natural Draught Zig Zag Kiln (NDZZK)
2) High Draught Zig Zag Kiln (HDZZK)
Moving Ware Kiln
a) Tunnel Kiln
b) Vertical Shaft Brick Kiln (VSBK)
2. A Brief Review of Different Types of Kilns
Clamp
The clump is the ancient technology which was practiced from 4000 BC. It is the basic type
intermittent kiln without any permanent structure. It has no stack chimney. Green bricks are piled
up on a bed of fuel (either coal or wood). The fuels are also fed through the tunnels which were
made by 2.0-2.5 cm among the bricks. A clamp is piled with alternate layers of green bricks and
fuel. Dry grass, cow dung, husk, wood, and coal are used as fuel in the clamp. A clamp can
produce 100000 bricks in a one firing. A.i.b) Scove and A.i.c) Scotch are the two relative
improved variations of clamp. The firing process is more or less same but the only variation is that
a scove kiln has the outer wall is plastered (scoved) by clay material to prevent the heat loss
whereas in a scotch kiln the outer wall is built permanently with the mortar. Clamp firing process
is generally practiced in African countries and Peninsular India.
Down Draught Kiln (DDK)
DDK is other types of the intermittent kiln where no chimney or stack has been provided to
disperse flue gas in the higher point of the atmosphere. In this system, bricks are fired in batches. It
has a rectangular or circular permanent walls and roof. The flue gases deflected from the roof and
then moved down ward to burn the green bricks. The kiln generally consists of two chambers. The
capacity of each chamber is 20000-40000 bricks per batch. DDK is one of the traditional methods
generally practiced in developing countries like India, Pakistan, and Bangladesh. DDK contributes
0.96% of total brick production in India.
Bull’s Trench Brick Kiln
The oval shaped arch less version of the continuous kiln is Bull's Trench Brick Kiln which was
invented by British engineer J. Bull in 1876. Bull's Trench kiln (BTK) has two types.
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Moving Chimney Bull’s trench Kiln (MCBTK)
It is one of the ancient methods of brick firing technologies. The shape of the Kiln is oval or
elliptical. In this kiln, two chimneys are moved by the firemen at regular time intervals to bring
forward in the firing zone. As soon as the firemen fed into coal or other biomass to MCBTK, it
produces black smoke with soot due to incomplete combustion of coal. The MCBTK is locally
termed as ‘Haowa Chully’ in Cooch Behar. Specific energy consumption in MCBTK is 1.2-
1.75MJ/kg bricks and specific coal consumption is 19-28 tons/100000 bricks. The firing of a 2.5
kg brick consumes 130gm coal. The total production of an MCBTK was 4-5 million bricks per
year. As this was a most polluting kiln in S.E Asia, it has been banned in India in 1996, in Nepal
2003.in Pakistan 2006 and Vietnam in 2010.
Fixed Chimney Bull’s Trench Kiln (FCBTK)
FCBTK is the improved version of MCBTK. It is a continuous moving fire kiln which is widely
used in South Asian countries. It is constructed by excavating a trench of about 6-9m wide, 2.0-
2.5m deep and 100-150m long. A gap has provided at the outer wall for easy access to the trench
for loading and unloading of bricks.
The FCBTK has two trenches with 6 sections each. After the bricks of one channel are fully brunt,
it is left over for few days to cool down and then unloaded. The other trench is loading in due
course with green bricks and firing process will continue. The FCBTK has provided a 22m to 30m
high chimney depending on the size of the kiln. It produces 15000-30000 bricks per day.
Hoffman Kiln
It was invented by F.E Hoffman in 1857 in Germany. It is a circular, large and permanent arched
kiln with a central chimney. It is one of the important continuous moving fire kilns. Hoffman kiln
has two variations-
Original Hoffman Kiln (OHK) , Hybrid Hoffman Kiln (HHK)
Both have the permanent structure which allows firing bricks even in the rainy season. The shape
is rectangular in both cases. They have 10-12 chambers with doors for loading and unloading of
bricks. The coal is charged from the top of the kiln.
The HHK is designed in such a way that at the time of firing bricks by dust coal, the waste heat is
transferred to the adjacent tunnel for drying of green bricks. The HHK lead to lower energy
consumption than original Hoffman kiln. HHK is generally used in China and Original Hoffman
Kiln in South East Asia. The production capacity of Original Hoffman Kiln is 10000-20000 bricks
per day whereas HHK has a production capacity of 50000 bricks per day. It reduced the fuel
consumption by 50% than FCBTK.
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Zig Zag Kiln
Zig Zag kiln is a clear, energy efficient and environment-friendly firing technology. It is
continuous, cross draught moving fire kiln. It is a modification of Hoffman kiln with zig zag
chamber in which the flue gas flows in a zig zag path. The zig zag firing concept was first used in
Buhres (1868) and Alois Habla modified it 1927. Zig Zag Kiln has two types-
Natural Draught Zig Zag Kiln (NDZZK) and High Draught Zig Zag Kiln (HDZZK)
Both have a low height chimney at the centre of the kiln. They have several chambers which are
numbered 1 to 20. Every second chamber has a small door. These are guard walls with 1 green
brick thickness. The partition wall is alternatively attached to central island and boundary. Both
are popular in India, China, Nepal, Bangladesh and European Countries. IIT, Roorkee introduced
the HDZZK in 1967 with 24 chambers. The difference of NDZZK and HDZZK is that the airflow
inside the kiln. In NDZZK it is achieved by a chimney whereas in HDZZK it is done by a fan.
Moreover, the latter has greater energy and environmental performance than the previous.
Tunnel Kiln
Tunnel kiln is one of the low fuel consuming moving ware continuous kiln in which moulded
bricks to be burned are passed on roller wheel through a tunnel. It was invented in 1877 in
Germany. Later, it was popular in Asia, China and Vietnam. India has now only 5 kilns in this
type. As its SEC is higher (1.34-1.47 MJ/Kg), high emissivity and high construction cost, it was
failed to popular in underdeveloped and developing countries. Firing and drying are done
simultaneously in the tunnel kiln. It is the most advanced technology where a wide variety of
bricks are burnt with high quality. It has a better control over firing process.
Vertical Shaft Brick Kiln
Vertical Shaft brick kiln (VSBK) is a continuous, updraft, moving ware, energy efficient low
emissive kiln in which the fire remains stationary and counter current heat transfer is taken place
between hot flue gas and bricks.
VSBK was invented in China in 1958 and disseminated in India and South East Asia during the
1990s. India has now only about 110 brick kilns of such type.
VSBK was a rectangular shaped (1.0x1.5m to 1.75m x3.75m) with a height of 6-10m. I have two
or more shafts. The Shaft was bordered by a brick wall. All shafts are connected with chimney and
shaded by a roof. The capacity of production of VSBK is 8000-12000 bricks per day.
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3) Performance analysis of various types of Kiln
A comprehensive assessment of brick manufacturing technologies has been carried out in the
following section. Production of bricks requires burning about 110 million tons of coal and several
million tons of firewood in India (Heireli and Maithel, 2008). It is detrimental to the
environment. Different brick making technologies have exerted much energy utilization, variations
in production and financial constraints. The following sections discuss the various performances
relating to different technologies of brick making processes. These include…
• Energy performance
• Environmental performance
• Fuel performance
• Production and Product quality performance
• Financial performance
Table-1: Basic Information for measuring Performance of Brick Kilns
Technology
Emissions( g/kg of fired brick)
Sp
ecif
ic
Energ
y
Consu
mpti
on
( M
J/K
g
fire
d B
rick
) S
pec
ific
Coal
Consu
mpti
on
(Tons/
1000
Bri
cks)
Heat
requirement
(MJ/1000
Bricks)
Quantity of Fuel Required(
Tons/1000 Brick)
CO2 BC SPM SO2 CO SEC
Wood /
biomass Coal
Diesel/
Kerosene
A. i.a) Clamp Clamps do not have a chimney stack and
therefore, stack emissions can’t be
measured
3.12
51.5
17,000 1.10 0.26 0.16
A.i.b) Scove 2.90 16,000 1.00 0.59 0.36
A. i.c) Scotch 2.72 16,000 1.00 0.59 0.36
A. i.) DDK 282.4 0.29 1.56 0.28 3.78 2.97 23.5 15,500 0.97 0.57 0.35
B.i.a) MCBTK 290 0.35 1.32 0.75 3.22 1.48 21 14000 1.20 0.36 0.40
B.ii.b) FCBTK 131 0.13 1.18 0.66 2.00 1.32 47.5 4500 0.28 0.17 0.10
B.iii.a) Original
Hoffmann 125 0.08 0.45 0.59 3.22 1.36 21.5 2000 0.13 0.12 0.05
B.iii.b) Modern
Hoffmann 100 0.03 0.29 0.52 2.80 1.20 25.5 5000 0.31 0.19 0.11
B.iv.a ) NDZZK 105 0.02 0.22 0.44 0.29 1.06 17.5 3000 0.19 0.11 0.07
B.iv.b) HDZZK 105 0.01 0.24 0.32 1.62 1.03 16.5 3700 0.15 0.16 0.08
B.v) Tunnel Kiln 166 0.02 0.24 0.72 3.31 1.40 22.5 4,000 0.25 0.15 0.09
B.vi) VSBK 70.5 0.00
1 0.15 0.54 1.84 0.80 14 1800 0 0.105 0
Contd……………………..
Geo-Analyst , ISSN 2249-2909 December, 2015
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Technology Product Quality (%)
Production
(No of
bricks per
Day)
Annual Production
(million Bricks/year)
Production Cost
(Lakh)
Good Inferior Sludge
Minimum Maximum Minimum
Maxim
um
A. i.a) Clamp 50 30 20 10000-
200000 per
Batch
0.01 0.20 5 6
A.i.b) Scove 65 25 10 0.01 0.20 5 6
A. i.c) Scotch 75 20 5 0.01 0.20 8 10
A. i.) DDK 85 10 5
20000-
40000 per
batch
0.60 1.00 13 20
B.i.a) MCBTK 50 30 20 10000-
28000 4.00 5.00 22 25
B.ii.b) FCBTK 60 35 5 20000-
50000 8.00 10.00 32 35
B.iii.a) Original Hoffmann 85 10 5 40000 6.00 8.00 64 90
B.iii.b) Modern Hoffmann 90 5 5 50000 15.00 16.00 380 400
B.iv.a ) NDZZK 85 10 5 20000-
50000 6.00 8.00 35 40
B.iv.b) HDZZK 80 15 5 15000-
28000 5.00 6.00 40 45
B.v) Tunnel Kiln 95 2 3 50000 15.00 20.00 600 640
B.vi) VSBK 90 0 10 8000-12000 1.00 4.50 35 40
Source: Ref.1, 3, 4, 5
Energy Performance
Energy performance of brick kilns is measured on the basis of Specific Energy Consumption
(SEC). SEC is defined as the thermal energy (Mega Joule) required for burning of 1 kg of brick. It
is generally used as the parameter to measure the energy performance of brick kilns. The SEC is
measured by the following formula
SEC= ���
���� Where,
Mfbr = Mass of fired bricks produced during one firing cycle/batch
Hin = Total energy input ( External +Internal + Organic matter of Soil)
Geo-Analyst , ISSN 2249-2909 December, 2015
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to the kiln for the duration of one firing cycle/ batch. ………………(GKSPL manual)
SEC is measured by Mega Joule (MJ) energy. 1 MJ is equivalent to 34gram coal equivalent. Low
SEC indicates the more efficiency of the kiln. Table-1 shows the SEC of different Kilns. From the
following diagram, it is evident that Vertical Shaft Brick Kiln (VSBK) has the lowest SEC
requirement at 0.80MJ/kg of fired brick followed by Zig Zag Kilns (1.03 to 1.06 MJ/kg of fired
brick) and modern Hoffman Brick kilns (1.20 MJ/kg of fired brick). The diagram also shows that
Clamp kilns consumed highest energy (3.12 MJ/kg of fired brick) followed by Down Draught
Kilns (DDK) (2.97 MJ/kg of fired brick). The SEC of intermittent kilns is significantly high ranges
from 2.72-3.12 MJ/kg of fired brick whereas continuous kilns have lower SEC (0.80-1.48 MJ/kg
of fired brick). Moreover, Zig Zag, VSBK and Tunnel Kilns used electricity or Diesel for initial
firing and other mechanical works. So, an amount of 0.015 MJ/kg of fired brick, 0.03 MJ/kg of
fired brick, 0.3 MJ/kg of fired brick energy are required for Zig Zag (NDZZK), VSBK and Tunnel
kilns respectively. Fig-2 explains the range of SEC. The range of energy consumption is very high
in Clamp kilns (2.00-4.50 MJ/kg of fired brick) followed by DDKs (2.80-3.14 MJ/kg of fired
brick). The VSBK (0.54-1.10 MJ/kg of fired brick) has the lowest range of SEC and High Draught
Zig Zag Kiln (HDZZK) ranked second in terms of the range of energy consumption. Its range of
SEC is 0.95-1.11 MJ/kg of fired brick. Fixed Chimney Bull's Trench kiln (FCBTK) is common in
firing methods used in India. Its average SEC is 1.32 MJ/kg of fired brick and range of SEC is
1.10-.146 MJ/kg of fired brick. VSBK is, thus, 60% more efficient than FCBTK and 75% more
efficient than Clam kilns.
Fig-1: Specific Energy Consumption of different Kilns
3.122.90 2.72
2.97
1.48 1.32 1.36 1.20 1.06 1.031.40
0.80
0.000.501.001.502.002.503.003.50
MJ
/Kg f
ired
Bri
ck
Specific Energy Consumption of different Kilns
Geo-Analyst , ISSN 2249-2909 December, 2015
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Fig-2: Range of Specific Energy Consumption
Environmental performance
Brick kiln industry is the 3rd largest consumer of coal (After Power and Steel Section) consumed
24 million tons per year (about 8% of the total coal consumption of the country. The total amount
of Coal and biomass consumption is 35-40 tons/tons coal equivalent (TCE) (Eco-brick). The cost
of energy in brick manufacturing is about 35% of total cost of the plant. The huge amount of coal
and biomass combustion causes environmental pollution by emitting Carbon dioxide (CO2), Black
Carbon (BC), Sulphur dioxide (SO2), Carbon Mono Oxide (CO), NOx and Suspended Particulate
Matter (SPM). Thus, environmental assessment has to be discussed on the basis of the above
pollutants.
Performance of CO2
CO2 emissions are directly related to moisture (%), ash (%), volatile matters (%), Fixed Carbon
contents present in the coal and biomass. From the figure, it is clear that MCBTK and DDK kilns
emit maximum CO2 (290 and 282 g/kg of fired brick) followed by Tunnel Kiln(166 g/kg of fired
brick). The least CO2 emitter is VSBK which emits 70.5 g/kg of fired brick CO2. According to J.
S. Kamyotra Director, Central Pollution Control Board, New Delhi, out of total production of
bricks in India, 74% achieved through BTKs and 21% through Clamps. Thus FCBTKs and
Clamps contribute maximum emission of CO2.
2.00
1.201.10
2.80
1.21 1.521.02 0.95 1.34
0.54
4.50
1.751.46
3.14
1.52 1.70
1.21 1.111.47
1.10
0.00
1.00
2.00
3.00
4.00
5.00
Clamp
kilns
MCBTK FCBTK DDK Original
Hoffman
Modern
Hoffman
NDZZK HDZZK Tunnel VSBK
MJ/
kg
of
fire
d b
rick
Range of Specific Energy Consumption
Minimum Maximum
Fig-2.a):
Performance of SPM and CO
Suspended Particulate Matter (SPM) is defined as the suspended particle of less than 100 µm
diameter in the atmosphere. Emissions of SPM and CO are due to incomplete combustion of coal
and biomass. DDK has the highest emission factors for both SPM and CO. MCBTK and Tunnel
Kiln ranks 2nd and 3rd position as CO emitters. The lowest emitters of CO is NDZZKs (0.29)
followed by HDZZK (1.62). On the contrary, due to the use of dust coal as in
constant combustion VSBK (0.15), Tunnel Kiln and HDZZK (0.24) and NDZZK (0.22) are the
lowest emitters of SPM.
Emissions of Black Carbon and SO
Emission of SO2 mainly depends on the sulphur content in the fuel. The
biomass than coal have the lowest sulphur contents and hence, lowest SO
0
100
200
300
NA NAg/k
g o
f fi
red
bri
ck
Geo-Analyst , ISSN 2249-2909 December,
22
a): Emissions of CO2 from Brick Kilns
Suspended Particulate Matter (SPM) is defined as the suspended particle of less than 100 µm
diameter in the atmosphere. Emissions of SPM and CO are due to incomplete combustion of coal
and biomass. DDK has the highest emission factors for both SPM and CO. MCBTK and Tunnel
Kiln ranks 2nd and 3rd position as CO emitters. The lowest emitters of CO is NDZZKs (0.29)
followed by HDZZK (1.62). On the contrary, due to the use of dust coal as internal fuel and
constant combustion VSBK (0.15), Tunnel Kiln and HDZZK (0.24) and NDZZK (0.22) are the
Emissions of Black Carbon and SO2 from Brick Kilns
mainly depends on the sulphur content in the fuel. The kilns that use more
biomass than coal have the lowest sulphur contents and hence, lowest SO2 emission. DDK and
NA
282.4 290
131 125100 105 105
166
70.5
Emissions of CO2
December, 2015
Suspended Particulate Matter (SPM) is defined as the suspended particle of less than 100 µm
diameter in the atmosphere. Emissions of SPM and CO are due to incomplete combustion of coal
and biomass. DDK has the highest emission factors for both SPM and CO. MCBTK and Tunnel
Kiln ranks 2nd and 3rd position as CO emitters. The lowest emitters of CO is NDZZKs (0.29)
ternal fuel and
constant combustion VSBK (0.15), Tunnel Kiln and HDZZK (0.24) and NDZZK (0.22) are the
kilns that use more
emission. DDK and
70.5
Geo-Analyst , ISSN 2249-2909 December, 2015
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HDZZK have the lowest SO2 emissions. MCBTK (0.75) and Tunnel kiln (0.72) emit highest SO2
followed by FCBTK (0.66) as they use more coal for the firing of bricks. The Fig 2.c) reveals that
BC is highest in MCBTK (0.35) followed by DDK (0.29). It is very much negligible in the case of
VSBK (0.001) followed by HDZZK (0.01). FCBTK emits a considerable amount of Black Carbon.
Black Carbon emission mainly depends on the nature of carbon bonding of the coal. It traps visible
light creating the temperature rise.
Fig-2.c): Emissions of Black Carbon and SO2 from Brick Kilns
Fuel Performance
As mentioned earlier coal and biomass are the main sources of energy for the firing of bricks.
Combustion of coal in different kilns differs significantly because of performance kiln technology.
The Gross Calorific value (GCV) of coal of different origin and various biomasses is different.
Further, kiln performance also depends on firing temperature and loss of heat during firing and
drying process. Table 2 describes the different fuel (External and Internal) properties and their
Gross Calorific Value (GCV).
0.29
0.35
0.13
0.08
0.03
0.02
0.01
0.02
0.001
NA
NA
NA
0.28
0.75
0.66
0.59
0.52
0.44
0.32
0.72
0.54
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
A. i.a) Clamp
A.i.b) Scove
A. i.c) Scotch
A. i.) DDK
B.i.a) MCBTK
B.ii.b) FCBTK
B.iii.a) Original Hoffmann
B.iii.b) Modern Hoffmann
B.iv.a ) NDZZK
B.iv.b) HDZZK
B.v) Tunnel Kiln
B.vi) VSBK
g/kg of fired brick
Emissions from Brick Kilns
SO2 BC
Geo-Analyst , ISSN 2249-2909 December, 2015
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Table-2: Fuel Analysis
Types of Fuel Moisture (%) Ash (%) Volatile (%) Fixed Carbon
(%)
GCV
(Kcal/kg)
GCV*
(MJ/kg)
A) External Fuel
a) Coal
i) Assam Coal .96-2.99 11.0-26.46 22.84-37.71 37.06-49.88 4764-5603 20-23
ii) Chandrapua
Coal
3.96-8.36 22.19-37.16 25.07-30.96 33.81-38.49 4077-4877 17-20
iii) Jharia Coal .31-1.48 34.47-46.89 15.83-26.85 33.78-50.06 3520-5034 15-21
iv) Raniganj Coal 6.83-8.61 31.3-23.86 25.1-27.41 34.46-42.43 4607-5258 19-22
b) Biomass
i) Mustard Straw 5.38-9.09 3.1-6.3 70.47-73.79 16.51-17.1 3998-4306 16.5-18
ii) Rice Husk 5.63-19.4 17.4-23.89 48.26-55.95 14.35-14.92 3403-3471 14-15
iii) Cotton Straw 12.18 3.77 66.75 17.3 4219 17.5
iv) Saw dust 30.61 5.31 53.38 10.7 3235 13.5
B) Internal Fuel
i) Katni coal dust 1.92 45.77 19.66 3336 14
ii) Coal rejects of
thermal power
2.43 68.5 18.09 2049 8.5
*1 Kcal/kg = .0041868 Mega Joule/kg
Source: Ref.1 ,3, 4, 5
Performance of Heat Requirement
It is evident from the Fig.3.a that the heat requirement is higher in the traditional type of kilns
ranging from 14000-1700 MJ/1000 bricks. It is highest in Clamp kiln followed by Scove and
Scotch kiln (16000MJ/1000 Bricks). Movable Chimney Bull's Trench kiln (MCBTK) has also
higher requirements of heat (14000 MJ/1000 bricks). Among the modern kilns, VSBK has the
lowest requirements of heat (1800 MJ/1000 bricks) followed by original Hoffman Kiln
(2000MJ/1000 Bricks). The other modern technologies show the requirements of 3000-5000
MJ/1000 bricks for combustion of fired bricks.
Geo-Analyst , ISSN 2249-2909 December, 2015
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Fig-3.a) Specific Coal Consumption
The performance of Specific Coal Consumption
Fig-3.b) Heat requirements
51.5
23.5
21.0
47.5
21.525.5
17.5 16.522.5
14.0
0
20
40
60
80
Clamp kilns MCBTK FCBTK DDK Original
Hoffman
Modern
Hoffman
NDZZK HDZZK Tunnel VSBK
ton
s/1
00
,00
0 b
rick
s
Specific Coal Consumption
Minimum Maximum Average
02,0004,0006,0008,000
10,00012,00014,00016,00018,000
MJ/
10
00
Bri
ck
Heat requirement
Geo-Analyst , ISSN 2249-2909 December, 2015
26
Quantity of Fuel required
The Fig 3.c incorporates the quantity of coal required for burning of clay bricks. Brick burning
processes may be intermittent or continuous. Intermittent kilns are generally traditional in nature
whereas continuous kilns are modern and modified in nature. The firing of green bricks required
coal, wood/biomass and diesel or kerosene as fuel. Most of the traditional kilns use more wood or
biomass for the firing of bricks. MCBTK has used highest amount of wood or biomass (1.20
tons/1000 bricks) followed by clamp kilns (1.00-1.10 tons/ thousand bricks). There is no need of
wood in case of VSBK. VSBK uses only coal and its requirement of coal is least (0.105 tons/1000
bricks) followed by Zig Zag and original Hoffman kiln. VSBK does not use diesel or kerosene.
The use of diesel or kerosene is the minimum for modern kilns. The traditional or intermittent
kilns even now use a considerable amount of diesel or kerosene for lit up the first fire and for
continuing the firing process.
Fig-3.c) Quantity of Fuel required
1.10
1.00
1.00
0.97
1.20
0.28
0.13
0.31
0.19
0.15
0.25
0
0.26
0.59
0.59
0.57
0.36
0.17
0.12
0.19
0.11
0.16
0.15
0.105
0.16
0.36
0.36
0.35
0.40
0.10
0.05
0.11
0.07
0.08
0.09
0
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40
A. i.a) Clamp
A.i.b) Scove
A. i.c) Scotch
A. i.) DDK
B.i.a) MCBTK
B.ii.b) FCBTK
B.iii.a) Original …
B.iii.b) Modern …
B.iv.a ) NDZZK
B.iv.b) HDZZK
B.v) Tunnel Kiln
B.vi) VSBK
Tons/1000 Brick
Quantity of Fuel Required
Diesel/ Kerosene Coal Wood / biomass
Production and Product quality performance
The Fig- 4a and 4b show the performance of production and final product quality of bricks
produced in different technologies of brick firing. Annual production and product quality is
highest in Tunnel kiln (15-20 Million bricks/year and 95% good bricks) followed by modern
Hoffman kiln (15-16 million bricks/year & 90 % good brick). The annual production, as well as
product quality, is inferior in traditional intermittent kilns like Clamp, Scove, Scotch, DDK, and
MCBTK. Annual production is also low in case of VSBK (1.0
its product quality is very much high (90%). Product quality of all modern continuous kilns is high
ranges between 80-95% only exception in DDK whose product quality is also high. Thus, it may
deduce that the more the modernizat
and product quality.
Fig
0.00
5.00
10.00
15.00
20.00
0.01 0.010.20 0.20
mil
lio
n B
rick
s/y
ea
r
Annual Production of Bricks
Geo-Analyst , ISSN 2249-2909 December,
27
Production and Product quality performance
show the performance of production and final product quality of bricks
produced in different technologies of brick firing. Annual production and product quality is
20 Million bricks/year and 95% good bricks) followed by modern
16 million bricks/year & 90 % good brick). The annual production, as well as
product quality, is inferior in traditional intermittent kilns like Clamp, Scove, Scotch, DDK, and
MCBTK. Annual production is also low in case of VSBK (1.0-4.5 Million Bricks/ year) through
its product quality is very much high (90%). Product quality of all modern continuous kilns is high
95% only exception in DDK whose product quality is also high. Thus, it may
deduce that the more the modernization and efficiency of firing process the more the production
Fig-4a) Annual Production of Bricks
0.01 0.60
4.00
8.006.00
15.00
6.00 5.00
15.00
1.000.20 1.00
5.00
10.008.00
16.00
8.006.00
20.00
4.50
Annual Production of Bricks
Minimum Maximum
December, 2015
show the performance of production and final product quality of bricks
produced in different technologies of brick firing. Annual production and product quality is
20 Million bricks/year and 95% good bricks) followed by modern
16 million bricks/year & 90 % good brick). The annual production, as well as
product quality, is inferior in traditional intermittent kilns like Clamp, Scove, Scotch, DDK, and
llion Bricks/ year) through
its product quality is very much high (90%). Product quality of all modern continuous kilns is high
95% only exception in DDK whose product quality is also high. Thus, it may
ion and efficiency of firing process the more the production
4.50
Geo-Analyst , ISSN 2249-2909 December, 2015
28
Fig-4b) Product Quality of Bricks
Financial Performance
An appraisal of the financial performance of various technologies is presented in the Fig-5.
Clamp Kilns including Scove and Scotch kilns require lower investments. The Tunnel kiln and
Modern Hoffman technologies require large capital investment (75-100% more than clamp kilns).
VSBK, Zig Zag Kilns have the similar production cost and it varies from 35-40 lakh rupees.
VSBK has the smaller in size and Tunnel kilns have larger enterprise. So, financial performance
mainly depends on modernization and size of the kiln.
50
6575
85
5060
8590
8580
9590
3025
2010
3035
105
1015
2 0
2010
5 5
20
5 55
5 5 310
0
20
40
60
80
100
% o
f B
rick
s
Product Quality
Good Inferior Sludge
Conclusion and Recommendations
The economy of India is growing at a faster rate with rapid urbanization. This leads to a great
demand of bricks. But the brick sector of India is characterized by traditional manufacturing
process with considerable emissivity
labour with steadily slow mechanization process. The brick manufacturing is unorganized in and
small scale in nature with financial constraints. It uses top soil as raw material which
agriculturally fertile. A composite score on the basis of performance of the variable chosen is
prepared and tabulated in the Table No 4
score the higher is performance and consequently, the fewer
is clear that the VSBK technologies would be the right option for cleaner technologies as its score
is lowest. Zig Zag kilns may be the right option
investment and higher production rate and more energy and pollution efficiency. Further, the
Natural Draught Zig Zag Kiln (NDZZK) is more efficient than High Draught Zig Zag (HDZZK).
0
500
1000
5
6
Ru
pe
es
in L
ak
h
Geo-Analyst , ISSN 2249-2909 December,
29
Fig-5: Financial Performance
Conclusion and Recommendations
The economy of India is growing at a faster rate with rapid urbanization. This leads to a great
demand of bricks. But the brick sector of India is characterized by traditional manufacturing
emissivity causing pollution. The sector still relies on low-cost manual
labour with steadily slow mechanization process. The brick manufacturing is unorganized in and
small scale in nature with financial constraints. It uses top soil as raw material which
agriculturally fertile. A composite score on the basis of performance of the variable chosen is
Table No 4. The Fig 6 shows the composite score. The lower is the
score the higher is performance and consequently, the fewer are constraints or vice versa. Thus, it
is clear that the VSBK technologies would be the right option for cleaner technologies as its score
is lowest. Zig Zag kilns may be the right option for substitution of FCBTK because of low capital
her production rate and more energy and pollution efficiency. Further, the
Natural Draught Zig Zag Kiln (NDZZK) is more efficient than High Draught Zig Zag (HDZZK).
5
8
13
22
3264
380
35
40
600
35
6
6
1020
2535
90400
4045
640
40
Production Cost
December, 2015
The economy of India is growing at a faster rate with rapid urbanization. This leads to a great
demand of bricks. But the brick sector of India is characterized by traditional manufacturing
cost manual
labour with steadily slow mechanization process. The brick manufacturing is unorganized in and
small scale in nature with financial constraints. It uses top soil as raw material which is
agriculturally fertile. A composite score on the basis of performance of the variable chosen is
shows the composite score. The lower is the
are constraints or vice versa. Thus, it
is clear that the VSBK technologies would be the right option for cleaner technologies as its score
for substitution of FCBTK because of low capital
her production rate and more energy and pollution efficiency. Further, the
Natural Draught Zig Zag Kiln (NDZZK) is more efficient than High Draught Zig Zag (HDZZK).
Minimum
Maximum
In India, about 72 % kilns are Fixed Chimney Bull’s Trench (FCBTK) which is ranked 6
performance. Movable Chimney Bull's Trench Kiln has been banned in India in 1996. The other
traditional kilns are more inefficient and should be banned. The Tunnel kiln is more capital
intensive and it requires more mechanization. Thus, it may take lots of
The VSBK would be the best choice but it has low productivity, unavailability of very high quality
of clay and limited market make it unpopular.
Finally, the present study recommends for adopting the following measures for cl
efficient kiln technologies in India
• The initiative should be taken to encourage for adopting Zig Zag and VSBK technologies.
• Encouragement should be given to the kiln owners to use fly ash instead of top soil.
• Brick production should be
bricks etc.
• The policy should be framed for using more renewable energy.
• Proper environmental monitoring should be ensured by the government.
• Last but not least the traditional processes of brick
and replaced by modern technologies.
Fig
164.5 162.0 158.5
0.0
50.0
100.0
150.0
200.0
Co
mp
osi
te S
core
Gross performance of Brick Kilns
Geo-Analyst , ISSN 2249-2909 December,
30
In India, about 72 % kilns are Fixed Chimney Bull’s Trench (FCBTK) which is ranked 6
erformance. Movable Chimney Bull's Trench Kiln has been banned in India in 1996. The other
traditional kilns are more inefficient and should be banned. The Tunnel kiln is more capital
intensive and it requires more mechanization. Thus, it may take lots of time to popularize in India.
The VSBK would be the best choice but it has low productivity, unavailability of very high quality
of clay and limited market make it unpopular.
Finally, the present study recommends for adopting the following measures for cleaner and more
iln technologies in India-
The initiative should be taken to encourage for adopting Zig Zag and VSBK technologies.
Encouragement should be given to the kiln owners to use fly ash instead of top soil.
Brick production should be diversified like the production of hollow bricks, perforated
The policy should be framed for using more renewable energy.
Proper environmental monitoring should be ensured by the government.
Last but not least the traditional processes of brick making technologies should be banned
and replaced by modern technologies.
Fig-6: Gross Performance of Brick Kilns
158.5
125.0148.0
111.0
93.5 97.069.0 82.0
92.5
58.0
Gross performance of Brick Kilns
December, 2015
In India, about 72 % kilns are Fixed Chimney Bull’s Trench (FCBTK) which is ranked 6th
in
erformance. Movable Chimney Bull's Trench Kiln has been banned in India in 1996. The other
traditional kilns are more inefficient and should be banned. The Tunnel kiln is more capital
time to popularize in India.
The VSBK would be the best choice but it has low productivity, unavailability of very high quality
eaner and more
The initiative should be taken to encourage for adopting Zig Zag and VSBK technologies.
Encouragement should be given to the kiln owners to use fly ash instead of top soil.
diversified like the production of hollow bricks, perforated
making technologies should be banned
Geo-Analyst , ISSN 2249-2909 December, 2015
31
Table 4: Composite Scores of Brick Kiln Performance
Technology 1. Emissions( g/kg of fired brick)
2.Specifi
c
Energy
( MJ/Kg
fired
Brick)
3.Specific
Coal
(Tons/1000
Bricks)
4.Quantity of Fuel Required
(Tons/1000 Brick)
CO2 BC SPM SO2 CO SEC Min Max
Wood /
biomass Coal
Diesel/
Kerosene
A. i.a) Clamp 10 10 10 10 10 12.0 10.0 11.0 10.0 8.0 8.0
A.i.b) Scove 10 10 10 10 10 10.0 10.0 11.0 10.0 11.0 10.5
A. i.c) Scotch 10 10 10 10 10 9.0 10.0 11.0 10.0 11.0 10.5
A. i.) DDK 9.0 8.0 9.0 1.0 9.0 11.0 7.0 6.0 8.0 10.0 9.0
B.i.a) MCBTK 8.0 9.0 8.0 9.0 6.5 8.0 4.0 8.0 9.0 9.0 12.0
B.ii.b) FCBTK 6.0 7.0 7.0 4.0 4.0 5.0 9.0 6.0 6.0 6.0 6.0
B.iii.a) Original Hoffmann 5.0 6.0 6.0 6.0 6.5 6.0 5.0 2.0 2.0 3.0 2.0
B.iii.b) Modern Hoffmann 2.0 5.0 5.0 4.0 5.0 4.0 8.0 7.0 7.0 7.0 7.0
B.iv.a ) NDZZK 3.5 3.5 2.0 3.0 1.0 3.0 3.0 3.0 4.0 1.0 3.0
B.iv.b) HDZZK 3.5 2.0 3.5 2.0 2.0 2.0 2.0 4.0 3.0 5.0 4.0
B.v) Tunnel Kiln 7.0 3.5 3.5 8.0 8.0 7.0 6.0 5.0 5.0 4.0 5.0
B.vi) VSBK 1.0 1.0 1.0 5.0 3.0 1.0 1.0 1.0 1.0 1.0 1.0
Contd..........
Technology 5. Product Quality (%)
6. Annual Production
(million Bricks/year)
7. Production Cost
(Lakh) Composite
Score Good Inferior Sludge Minimum Maximum Minimum Maximum
A. i.a) Clamp 11.5 10.5 11.5 10.0 10.0 1.0 1.0 164.5
A.i.b) Scove 9.0 9.0 9.5 10.0 10.0 1.0 1.0 162.0
A. i.c) Scotch 8.0 8.0 5.0 10.0 10.0 3.0 3.0 158.5
A. i.) DDK 5.0 5.0 5.0 6.0 9.0 4.0 4.0 125.0
B.i.a) MCBTK 11.5 10.5 11.5 7.0 7.0 5.0 5.0 148.0
B.ii.b) FCBTK 10.0 12.0 5.0 3.0 3.0 6.0 6.0 111.0
B.iii.a) Original Hoffmann 5.0 5.0 5.0 4.5 4.5 10.0 10.0 93.5
B.iii.b) Modern Hoffmann 2.5 3.0 5.0 1.5 2.0 11.0 11.0 97.0
B.iv.a ) NDZZK 5.0 5.0 5.0 4.5 4.5 7.5 7.5 69.0
B.iv.b) HDZZK 7.0 7.0 5.0 6.0 6.0 9.0 9.0 82.0
B.v) Tunnel Kiln 1.0 2.0 1.0 1.5 1.0 12.0 12.0 92.5
B.vi) VSBK 2.5 1.0 9.5 5.0 8.0 7.5 7.5 58.0
Source: Compiled by the authors
Geo-Analyst , ISSN 2249-2909 December, 2015
32
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