2.07 GWC Compost Manual

TOPSOILS OF AUSTRALIA PTY. LTD.

Manual for operators

Compost Plant

Written by Faye Milroy, Prior Training. (03) 9386 8145 Technical assistance was provided by John Karounos, Brian Jeffrey, and John Cowey from Geelong Wool Combing Ltd and Topsoils of Australia Pty Ltd. July 2003

Contents Section 1: Introduction 1

1.1 The training program 1 1.2 Operator tasks 2 1.3 The top-making process at GWC 3 1.4 Overview of the composting process 5 1.5 The Environmental Management System 6 1.6 Word list 7

Section 2: Occupational Health and Safety 9

2.1 Personal protective equipment 9 2.2 Safety in the compost plant 10

Section 3: Compost plant equipment and functions 12

3.1 Blending plant 12

3.2 Rolling stock 15 Section 4: Operating procedures 16

4.1 Suggested shift routine 16 4.2 Operating procedures for the compost blending plant 21 4.3 Operating the sludge collection system 22 4.4 Management of windrows 24 4.5 Compost stock level reporting 26 4.6 Sampling and testing procedures 28 4.7 Loading trucks 30

Section 5: Documentation 31 Section 6: Maintenance and troubleshooting 32

6.1 Regular maintenance and cleaning 32 6.2 Normal operating conditions 34 6.3 Using the SCADA to monitor operations 35

Section 7: Assessment 37

7.1 The assessment procedure 37 7.2 Checklist of operator tasks 38 7.3 Oral questions Compost plant operator 39

Compost Plant Operator Manual

July 2003 1

Section 1: Introduction 1.1 The training program The purpose: To train you to operate and monitor the Compost Plant efficiently and safely, with little supervision in accordance with company enterprise agreements. Training objectives: At the end of this training the operator will be able to:

1. explain the function of the compost plant 2. explain and demonstrate the major duties of the compost plant operator, including

a. materials handling b. documentation and communication c. monitoring compost plant functions d. monitoring quality and taking samples e. operating and adjusting composting equipment f. chemicals handling g. following safety procedures h. performing basic maintenance

Assessment methods:

1. practical demonstration of competency on the compost plant equipment, according to the checklist at the back of this manual

2. satisfactory answers to oral test questions relating to compost plant operations and the monitoring of composting functions

Note that a compost plant operator needs to have:

a heavy truck licence (manual)

a loader permit

a forklift licence


July 2003 2

1.2 Operator tasks The duties for the compost plant operator include:

1. Conducting materials handling operate a truck, loader, tractor, water cart, windrow turner and fork lift handle bulk materials, such as fertiliser, sawdust, fresh / mature compost

2. Working with documentation (paper and electronic)

read and maintain compost records record despatch dockets maintain vehicle log books maintain plant fault log

3. Communicating with others

explain compost functions and operations talk to delivery personnel and visitors communicate with ETP and other operators

4. Working without supervision

plan and prioritise own work

5. Interpreting and monitoring compost plant technology SCADA computer screens

6. Operating and adjusting compost plant equipment

process all bio-sludge and GWC waste streams to correct ratio maintain level in feedstock hoppers remove fresh compost to windrow area daily maintain sawdust supplies clean up and dispose of general waste load compost into trucks ensure proper running and maintenance of conveyors

7. Managing the windrows

monitor and record windrow temperatures weekly turn and water windrows weekly maintain, and ensure access in, windrow area (fill in pot-holes, etc) maintain leachate dams

8. Performing basic maintenance

regular cleaning and maintenance of rolling stock fixing basic problems with equipment ensure regular inspection / service on rolling stock and plant equipment

9. Monitoring compost quality

regular sampling and testing of compost monitoring temperature and moisture levels

10. Following safe work practices

use appropriate personal protective equipment observe plant safety procedures refer to and follow Material Safety Data Sheets (MSDS)


July 2003 3

1.3 The top-making process at GWC our raw material supplier

1. Receivals/Wool Store Bale specifications are checked. Bale lots stacked together.

2. Opening and blending Compacted bales are opened. Wool bales are blended into lots. Dust, dirt and seeds sent to storage

bins for compost

3. Scouring Wool is washed in detergent to remove

grease, sweat (suint) and dirt. Wool is rinsed and dried. Wool blended and anti-static oil added

6. Gilling (3 stages) Blends a number of slivers together. Makes the fibres parallel. Forms a sliver of even thickness. Forms a sliver of desired weight.

5. Carding A machine with a series of rollers

covered with metal pins. Untangles clumps of wool into

individual fibres. Removes vegetable matter and dust. Begins to make fibres parallel. Forms wool into a continuous sliver.

4. Effluent treatment Wool grease is extracted for lanolin. Sludge is removed for compost. Clean water is recycled or released to

sewer.

7. Combing Removes short fibres and small tangles

(neps). Removes remaining vegetable matter. Blends many slivers into one. Makes fibres parallel.

8. Finishing (2 stages) Completes process of blending and

making fibres parallel. Forms sliver of desired weight and

evenness. Winds sliver into a top or bump.

9. Pressing The tops are compressed into bales for

despatch. Waste by-products are also pressed into

bales for sale.

10. Despatch to customers


July 2003 4

1.4 Overview of the composting process A typical bale of greasy wool might contain only wool fibre:

All of these impurities must be removed from the wool. Most of the dirt, suint and grease is removed during the scouring process. The remaining dirt and vegetable matter is removed during opening, carding, gilling and combing. Traditionally, the wool grease is recovered and sold as a by-product as is the noil (short fibres). The rest of the waste (dust, dirt, vegetable matter) used to be disposed of to the rubbish tip, for which we paid a dumping fee. GWC became the first early stage wool processor to develop a system to recycle this waste and turn it into a saleable by-product compost. The compost plant receives GWC waste from three main sources:

When the compacted wool bales are opened and blended, the dust, dirt and seeds that are removed are transported by cyclone to a large storage bin.

The liquor from the scour contains dirt, sweat, wool wax and vegetable matter. The wool wax is separated and removed in grease recovery. The ETP treats the remaining liquor and recycles some water back to the scour, while the sludge passes through the bio-decanter before arriving at the compost plant.

The dust and airborne waste from carding is also cycloned to a storage bin. Other dry feedstock such as sawdust is sourced externally and stored in bins on site. During production, the dry material from hoppers 1 & 2 and the sludge from the bio all feed into the mixer. The ratio (weight) of each material in the blend is preset via the controller according to the required recipe. For some blends extra nutrients are also fed into the mixer from hopper 3. After mixing, the fresh compost is arranged in long heaped mounds called windrows. It takes about 4 months for the compost to mature, during which time the windrows are turned weekly. This ensures adequate oxygen levels to support the microbial activity. Moisture levels, pH and temperatures are also carefully monitored to make sure the composting process is optimised to ensure client satisfaction.

wool fibre 55-65%

moisture 5-10%

suint 5-8%

vegetable matter 2-5%

dirt, soil 10%

wool grease 12-15%


July 2003 5

Flow chart of the compost process


July 2003 6

1.5 The Environmental Management System GWC was the first wool processor in the world to obtain certification to the Environmental Standard ISO 14001 on the 22nd January 1998. Why is GWC/Topsoil concerned about environmental management?

Legal Requirements There are various agreements and regulations relating to the environment which have to be followed so that GWC/Topsoil can lawfully carry on its activities at Lara.

Marketing Demands

Certain clients require GWC/Topsoil to offer proof that our operations are carried out in a manner that does not harm the environment.

Cost Savings Reduction in waste and recycling should deliver cash savings.

Neighbourhood Relations GWC/Topsoil can have an effect on neighbours from the emission of noise, dust or odours. We have procedures in place to monitor each of these impacts.

Several environmental procedures and work instructions cover the compost plant. Your trainer will take you through the procedures and work instructions related to your job. It is your responsibility to follow these procedures, and to immediately report any environmental accident or incident.


July 2003 7

1.6 Word list

Aerobic A microbial process that uses oxygen to break down substances.

Anaerobic A microbial process that breaks down substances without oxygen, but produces odours.

Ausplume odour modelling

A method of determining the environmental impact of odour emissions generated by composting.

Australian Standard AS 4454

The quality standard that applies to composts, soil conditioners and mulches used by Topsoils.

Bio-aerosols Small air-borne particles which may contain bacteria or fungi spores.

Bio-sludge The resulting sludge from the biological treatment of scouring liquors once the wool grease has been recovered.

Bulk Density A factor used to convert compost production tonnes into cubic metres (m3).

Example:

0.5 tonne fresh compost will fill a container measuring 1m3 therefore the BD is 0.5(tonne) divided by 1(m3) = 0.5.

So in a day's compost production of 120 tonnes divided by a BD of 0.5 = 240m3.

Compost Partially decomposed organic matter produced by microbial activity, and suitable for improving soil quality.

EC Electrical Conductivity - a measurement of the salinity in soils and composts.

Friable The term given to soil or compost that has a loose, crumbly texture.

Heavy metals A group of metals such as Lead and Mercury which are dangerous to humans and cannot be degraded by composting.

ISO 14001 Environmental Management System (standards) followed by Topsoil.


July 2003 8

Leachate Excess water that has run off or through the composting material.

MSDS Material Safety Data Sheet

Pasteurized compost Compost which has been subjected to a minimum temperature of 550C for at least three consecutive days.

Pathogens Harmful bacteria or viruses usually associated with sewage.

Pesticide residues Harmful chemicals sometimes found in soils and sludges, resulting from sprays used by farmers for controlling lice and other pests on sheep and livestock.

pH A measurement of the acidity or alkalinity of soil or compost. PH is measured on a scale from 1 to 14, with 7 being neutral. The pH becomes more alkaline as it rises above 7, and more acid as it falls below 7. The pH of the soil or compost affects the uptake of nutrients by plants

Plant propagules Weed seeds.

SCADA Supervisory Control and Data Acquisition; a computer programme used to monitor the batching process and retrieve information for making production and stock reports.

Scouring Washing out the dirt, sweat and wool grease from wool.

Suint Sweat produced by sheep that is removed during scouring and consists of Potassium salts.

Thermophilic process Aerobic microbial activity which produces heat between 440C - 800C during the composting maturation phase.

Water retention Ability of soils to hold moisture, affected by the level of organic matter (compost).

Windrow A row of heaped composting material.


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Section 2: Occupational health and safety 2.1 Personal protective equipment (PPE)

Hearing protection must be worn in the production areas, to protect your ears from machinery noise. Sound can damage your ears if it is too loud, too high in frequency, or you are exposed too often. With some noise your ears will hurt straight away, with other noise the damage to your ears will happen gradually over time.

You will not "get used to the noise."

You will get used to your loss of hearing!

Remember, once your ears are damaged they never get better.

Rigger's gloves are provided where required for manual work. Rubber safety gloves are provided when handling certain

chemicals and harmful substances.

Certain tasks require eye protection or breathing protection, or both.

For example, eye and breathing protection must be worn while performing any cleaning task that causes fibres, aerosols or dust to circulate in the air.

Face protection may also be necessary when handling certain

chemicals, to prevent being splashed or breathing in fumes.

Steel cap boots must be worn in all production areas.

Long hair should be tied back or covered when working near

machinery.

Safety vests must be worn around the compost plant so that

you are visible to drivers

Sunglasses, hat and sunscreen for sun/outdoor work


July 2003 10

2.2 Safety in the Compost Plant

Drive safely when using any vehicles around the plant.

Do not exceed 15 km/h

look out for pedestrians

make sure other drivers are aware of speed limits

be aware of extra hazards around wet areas

Because of vehicle hazards, monitor access of people to the plant.

all visitors must report to office first

drivers must be alert that other people around the work site

Use channel 7 on the hand held (CB) radio and notify all drivers if visitors or staff are nearby

Chemicals Know the hazards associated with the chemicals you use

in the compost plant

Refer to the MSDS for each chemical for safe handling procedures

Maintain a high standard of hygiene, particularly around food.

always wash your hands before eating

Emergency stops Know where the lanyards, on/off and emergency stop

buttons are located, in case of emergency.

Lock out procedure Isolation of equipment will be in accordance with Tag

Out and Lock Out Procedure, SAF- 001.

Make sure all equipment is tagged out/locked out before any cleaning or maintenance work

Do not start up any equipment that is locked out.


July 2003 11

Heavy lifting

Keep your back straight and let your legs do the lifting

Slips, falls

Take care when moving around the plant. Wet floors and steps can be slippery.

Always face machine when entering/exiting machine and have a firm grip of the handrail.

Compost Plant emergency procedures (Refer to work instruction) The following procedures outline what to do in the case of emergencies such as power failure and fire. These procedures are only to be followed if it is safe to do so.

Do not put yourself at risk to carry out these procedures. Power failure

If safe to do so:

Turn off power and air

Turn off and lock all machinery and rolling stock

Keep the keys on your person

Proceed to the assembly area. Resumption of power

Reset the plant.

Return all keys to designated location

Complete incident report Fire

In case of fire hazard hit the group emergency switch.

If time permits follow the steps under power failure, do not put yourself at risk.

Proceed to the assembly area.


July 2003 12

Section 3: Compost plant equipment & functions 3.1 Blending plant

Hopper 1 Collects and stores waste from the wool opener, the cards and cyclone system such as dust, dirt and vegetable matter premixed with sawdust.

Hopper 2

Collects and stores sawdust.

Hopper 3

Adds fertiliser in specified blend for Pine Gro mix

Discharge conveyor

Sludge silo

Hopper 2

Hopper 1


July 2003 13

Sludge silo Collects and stores bio-sludge from the effluent treatment plant (ETP).

Monopump

Pumps the bio-sludge from the ETP to the silo. Fitted with a protection device to prevent it running dry.

Mixer Combines material from the hoppers and silo. Functions such as feedstock ratios (by weight) and mixing times are centrally controlled. Total batch weight not to exceed 1,200kg.


July 2003 14

Conveyors Conveyor belts feed material from the hoppers to the mixer. A discharge conveyor transfers the mixer contents to a concrete hardstand.

Gravity fed air valve

Enclosed transport for biosludge into mixer

Testing equipment To test pH, temperature and moisture (Refer to section 4.6)

SCADA Controls all aspects of mixing plant including mixing time and mixing ratio.


July 2003 15

3.2 Rolling stock

Windrow turner Fitted with purpose-built device to turn outer material to the inside of the windrow. Weekly turning maintains the necessary oxygen, temperature and moisture levels.

Front-end loader Fitted with a bucket of certified volume (5.2m), used to add feedstock to the hoppers, to load trucks and to measure windrow stock levels.

Skip truck To pick up feedstock and transport compost.

Tractor To pull the water cart and windrow turner along windrows.

Forklift To fill the nutrient hopper.

Water cart To maintain moisture level in compost.


July 2003 16

Section 4: Operating procedures 4.1 Suggested shift routine A large part of the compost plant operators job is monitoring, that is checking that the equipment is running correctly and that the material is up to quality standards. To do this efficiently you will need to work to a routine so that problems can be quickly identified. An effective routine would include:

regular visual inspection of the equipment and windrows

regular checking of the SCADA screens

conducting temperature, pH and moisture tests at specified times

accurately completing compost records as required

handling deliveries and sales At the start of your shift

1. check the SCADA screens for anything that needs attention 2. check the vehicle and equipment maintenance logs for any problems 3. carry out a visual inspection of the blending plant 4. start production 5. carry out a visual inspection of the windrow area 6. conduct tests and complete records as required

A suggested route to follow is:

Site office SCADA

Blending plant

Vehicle checks /maintenance

Blending plant

Windrow tests /maintenance

Windrow area inspection


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What to check at each location on your route

Site office: At start of shift:

1. Check board for any messages/jobs to do. 2. Monitor operations on the SCADA screens:

silo level if low, check with ETP hopper levels if low, need to top up make sure everything is shut down from previous shift

3. Check equipment repairs log book. 4. Check vehicle log books.

At other times during shift:

1. Monitor operations on the SCADA screens:

trends screens overview screen

Production/Sales: 1. Check that mixer is empty before start up (or it will overflow). 2. Check if hoppers need filling. 3. Start up blending plant equipment. 4. Check to see that conveyor is clear of feed stock at all times. 5. Keep blending area clean and free of excessive build up 6. Sales: loading of trucks takes priority.

Vehicle checks 1. Perform checks on all vehicles as per log book. 2. Check loader radiator and air filter are clean.

Windrow Maintenance

1. Turn and water as per sheet in tractor, weekly. 2. Take temperature with probe and record details, weekly. 3. Construct new windrows as required and record details. 4. Conduct windrow stock level surveys and record details.

Area Maintenance: 1. Maintain work area and surrounds in a clean and safe manner. 2. Fill in pot holes and maintain a level surface.


July 2003 18

4.2 Operating procedures for compost blending plant (Refer to work instruction COM-WI-001) 4.2.1 Prestart checks

1. Check compressed air Check that the compressed air is turned on. The regulated pressure on hopper 2 and mixer gauges should be above 600 Kpa.

2. Set batch values From the main control panel touch screen:

enter Batching Control window through the Home window

set the desired batching values for hoppers 1 & 2 and sludge silo

The total batch weight should not exceed 1200kg

3. Check sludge silo setting In the Sludge Silo Batching Control window, make sure that the time/weight cell (top right hand corner) reads weight.

4. Set batch run time Enter Run Features window, set the Batch Time value to 10-20 seconds.

5. Reset alarms Reset any alarms that are being reported in the Safety Alarms window.

6. Fill hoppers Fill hoppers 1 and 2 to maximum level.

7. Check area is clear Check that all personnel are clear from the equipment.

4.2.2 Mixer load The mixer load increases as the ingredients blend. To protect it against overload, the mixer is fitted with a load monitor. Should the mixer reach 95% of its rated load, the discharge door will open immediately and empty the mixer contents.

Check the following:

1. Batch weights The preset batch weights must be set correctly and not exceed 1200kg.

2. Discharge time The discharge time must be sufficient to empty the contents of each batch.

3. Mixer is empty Make sure the mixer is empty before starting up, as the contents will upset the batch weights.


July 2003 19

4.2.3 Blending system start-up - Local Touch Screen (refer to attached Flow Diagram 1)

1. Turn key ON Turn the Master Control key to the on position. Note: #1 and #2 'Ready to Fill' lights should be lit, not flashing. Check to see that mixer is empty.

2. Select product Usually Topsoil or GWR

3. Select manual Enter the Manual window and select Manual mode.

4. Select Auto In the 'Manual' window select 'auto' to start the batching process.

Enter the 'auto mode' screen and ensure that: i) the 'Automatic' cell is flashing ii) the 'Resume/Suspend' cell is reading 'Suspend'.

Note: if the batching plant does not start tap the 'Reset' cell followed by the 'Start Cycle' cell.

5. Alarm A local audio alarm, warning automatic start-up of the batching hoppers, will sound 10 seconds before every new batching cycle.

6. Filling hoppers The filling of hoppers 1 & 2 can only be done when the Ready To Fill light is lit. Do not attempt to fill the hoppers unless the 'Ready to Fill' lights are lit or flashing.

Should the contents of H1/H2/Silo become less than their preset batch weights, the relevant Ready to Fill light will flash. Further blending will stop until the condition is fixed.

The contents of hoppers 1 & 2 should be maintained at a good level to avoid excessive action of the electric vibrators mounted on the sides of each hopper.

7. Mixer discharge An alarm will sound between 5-10 seconds before automatic start-up of the mixer discharge conveyor.

8. Skip truck Skip is to catch the discharge at all times so that it can be taken to the windrows


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START AUTOBATCHING

MIXER RUN

HOPPER 1 CLOSE

HOPPER 2 CLOSE

HOPPER 2 OPEN

CONV 2 STOP

HOPPER 1 OPEN

CONV 1 RUN

CONV 2 RUN

AUTO STARTUPAUDIO ALARM

CHECK MINIMUMBATCH WEIGHT

H1/H2/SILO

CONV 1 STOP

VIBRATOR STOP

ILLUMINATE H2 'READY TO FILL'

LIGHT

VIBRATOR RUN

ILLUMINATE H1'READY TO FILL'

LIGHT

BRIDGE BREAKERSTOP

VIBRATOR STOP

VIBRATOR RUN

BRIDGE BREAKERRUN

EXTINGUISH H1/H2'READY TO FILL'

LIGHT

MIXER DISCH GATECLOSE

DISCHARGE CONVSTOP

MIXER DISCH GATECLOSE

MIXER DISCHDOOR OPEN

AUTO STARTUPAUDIO ALARM

DISCHARGE CONVSTART

SLUDGE SILOAUGER STOP

SLUDGE SILOAUGER RUN

AUGER DISCHGATE OPEN

AUGER DISCHGATE CLOSE

DROP PRESET BATCH WEIGHT

TIME DELAY

NOTE 1

ABOVE MIN

TIME DELAY

TIME DELAY DROP PRESETBATCH WEIGHT

DROP PRESETBATCH WEIGHT

BATCH TIMER

TIME DELAY

TIME DELAY

TIME DELAY

TIME DELAY

TIME DELAY

NOTE 1: H1/H2/SILO 'READY TO FILL'LIGHTS WILL FLASH IMMEDIATELYIF THE RESPECTIVE HOPPER/SILOCONTENTS FALL BELOW THEMINIMUM BATCH WEIGHT.

MIXER LOADMONITOR

ENABLED

Flow Diagram 1


July 2003 21

4.2.4 Blending system shutdown

1. Select Manual When the last batch is discharging enter 'Manual' mode in 'Manual' window

The mixer discharge door will close and the mixer will continue to run.

2. Open discharge door Open the discharge door using the touch screen to discharge all of the mixer contents.

3. Turn off Turn everything off. Turn the 'Master Control' key to off then remove it to the site office keyboard.

Fresh compost As each skip is filled with fresh compost, it should be moved to the windrow area. Form the windrows in numerical order by batch number, according to the Windrow Layout Report Sheet.


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4.3 Operating the sludge collection system (refer to attached Flow Diagram 2).

The Monopump sludge collection system works independently of the Compost Blending Plant. It pumps bio-sludge from the Effluent Treatment Plant (E.T.P.) to the sludge silo at the eastern side of the blending plant.

The sludge silo has a nominal capacity of 27,000 kgs.

The Monopump is located on the north wall of the E.T.P. 4.3.1 Automatic Control

1. From the Compost Main Control Panel touch screen enter the Monopump window and select ON for normal operation.

2. The pump control will automatically place the Monopump in standby mode when the sludge level in the Monopump hopper falls to the low position.

3. When the silo reaches a capacity of 23,000 kgs the Silo Full alarms are enabled in the E.T.P. The operator can then hold back the bio-sludging.

4.3.2 Manual Control

1. The monopump manual control push button is located adjacent to the hopper outside the E.T.P.

4.3.3 Monopump protection The monopump is fitted with a pressure monitoring device to protect the pump from running dry. Biosludge will require between 2-10 bar to pump it into the sludge silo.

If the pump pressure falls below the pre-set pressure for 60 seconds, the monopump system will automatically shut down into stopped mode. This is indicated by a flashing red light in the ETP control room and above the North exit door.

Check that the monopump level sensor is clean, free of wet sludge and that the level in the monopump hopper is about 10%. Restart the monopump from the manual control push button located adjacent to the monopump hopper, or from the touch screen in the compost batching plant.

4.3.4 By-Pass

When filling the sludge silo in decanter by-pass mode, the batching system must be turned OFF. This is for two reasons:

To maintain accuracy of the daily sludge tally To prevent overfilling of the mixer with biosludge

The by-pass system fills the silo in 1 2 hrs (27,000 kgs).


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Flow Diagram 2

SELECTMONOPUMP 'ON'

MONOPUMP RUN

LOCAL MONOPUMPMANUAL CONTROL

PUSHBUTTON

EXTINGUISH 'SILOFULL' LIGHT IN

E.T.P/SILO

MONOPUMPSTANDBY

MONOPUMP RUN

AUTO CHECKMONOPUMP

HOPPER LEVEL

CONSTANT 'SILOFULL' LIGHT IN

E.T.P/SILO

SILENCE 'SILOFULL' SIREN IN

E.T.P.

SOUND 'SILO FULL'SIREN IN E.T.P.

FLASH 'SILO FULL'LIGHT IN E.T.P/

SILO

SILO LEVELABOVE 27000KG

SILO LEVELBELOW27000KG

MONOPUMPHOPPER LEVELABOVE 80%

MONOPUMPHOPPER LEVELBELOW 10%

ALARMS

'ACKNOWLEDGESIREN' PUSHBUTTON

'ACKNOWLEDGESIREN' PUSHBUTTON

SILO LEVELBELOW 27000KG

AUTOMATIC CONTROL

MANUAL CONTROL

SELECTMONOPUMP 'OFF'

FAST FLASH'MONOPUMP

STOPPED' LIGHT INETP

FAST FLASH'MONOPUMP

STOPPED' LIGHT INETP

PUMP PRESSUREBELOW 5 BAR FOR60 SECONDS


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4.4 Management of windrows Good windrow management ensures correct oxygen, moisture and temperature levels are maintained during the maturation period.

4.4.1 Windrow shape 1. The windrow is constructed with a parabolic (curved) profile.

The initial size of 1.7m high x 5.5m wide at the base gives maximum natural ventilation through the mix.

1.7m

5.5m

2. Each windrow will be either 200m or 300m in length running east/west. Allow 8.0m between windrow centres for machinery access.

8.0m

3.4m

3. A layout identifying each windrow and its age will be maintained in the Topsoil spreadsheet.


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4.4.2 Windrow turning 1. To maintain the oxygen level for the thermophilic (bacteria) process

windrows must be turned once per week. 2. Windrow moisture level must be kept between 40% - 60%. Direct a jet of

water into the top of the windrow along its length, prior to turning. This will avoid leaching.

3. Windrows are turned using a windrow turner fitted with an inverter conveyor. This ensures that the material on the outside of the windrow is turned to the inside each turning.

Above: Windrow turning

Below: Windrow survey

Separate stockpile


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4.5 Compost stock level reporting

4.5.1 Windrow Survey Method A loader fitted with a bucket of certified volume (5.2m) will be used to survey the stock level of a windrow. (Check ISO procedure)

1. Remove 52m3

(10 buckets)

Mark the start of the windrow you are surveying. Using the loader, move 52m3 (10 buckets) of

compost material from the end of a windrow. Form the removed compost into a separate stockpile.

Measure the distance of the space left from the material you have removed.

Calculate the volume factor (m3 per linear metre). Example: 52m3 removed, leaving a space of 8 metres

52

8

2. Calculate stock level Measure the original length of the windrow. (i.e. the length before you removed the 10 buckets)

Calculate the full windrow stock level by multiplying the volume factor by the original length of the windrow.

Example: length of complete windrow is 250 metres Windrow volume = 6.5 x 250 = 1,625 m3

3. Repeat for other windrows

Use this method to determine the stock level on all batches 4 months old and over. This survey method is used on all applicable batches to report compost stock levels at the end of each month until the batch is exhausted.

4. Adjust stock levels Include batch numbers on each despatch docket so that stock adjustments can be made and reported on a batch-by-batch basis at the end of each month.

Subtract the docket book stock level from the surveyed stock level to calculate any discrepancies.

= 6.5 m3 per linear metre


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4.5.2 Reduction Factor The reduction factor is calculated automatically by computer on all batches 4 months old and over. This is done by dividing the surveyed stock level by the fresh compost produced.

The typical reduction factor is between 30-35%, due to biological activity and wind loss. A higher reduction factor must be reported as this would not be due to natural factors.

A log will be kept of the age and reduction factor for each batch so that the historical reduction factor can be monitored.

The reduction factor of all batches at 4 months old will be averaged every 12 months, and used to correct the stock level of all batches under 4 months old.

4.5.3 Feedstock Bulk Density The moisture content in the sawdust feedstock markedly affects volume when converting the fresh compost from tonnes to cubic metres. To compensate when sawdust is noticeably wet or dry, apply the measured bulk density to the days production tally instead of the 0.5 average.

4.5.4 Stockpiling Mature Compost Should space constraints or weather conditions make it necessary to stockpile mature compost, each batch will be kept in discrete stockpiles prior to despatch. All windrows from the same batch are formed into one stockpile. The relevant batch number can then be recorded in the despatch docket book.

4.5.5 Batch Hopper Calibration Yearly calibration checks are done on all batch hoppers and silos fitted with weighing capability, to ensure accurate recording of input feedstock. The frequency of these checks is detailed in Environmental Monitoring Programme, GWC-240. Certification is recorded in the Environmental Management Programme.


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4.6 Sampling and testing procedures

Sample or test Method

Windrow core temperature Weekly.

1. Heat within the windrow indicates the level of thermophilic microbe activity. It is important that all windrow material is kept for long periods above 55oC.

2. Temperature is recorded at about 50m intervals along one side of the windrow, starting at least 10m from the end. This is done prior to turning, and recorded on the Weekly Windrow Layout Report.

3. Insert the length of the temperature probe at least 1m horizontally, approximately half way up the windrow height. The probe should reach the hot centre of the windrow.

Windrow moisture level Weekly.

1. Insert your arm into the windrow up to the elbow and grab a handful of compost.

2. Squeeze the sample in your hand and visually check its consistency. If it sticks together and forms a clump without water escaping between the fingers, the moisture level is OK.

3. If the compost is crumbly it will need watering.

Compost moisture content Carried out when required by customer.

Follow standard test procedure.


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Compost pH test Carried out when required by customer.

Follow standard test procedure.

Compost stock levels (Windrow survey)

End of the month. (Refer to section 4.5.1)

Compost trials When required, to trial new methods and/or materials.

Compost quality tests When required, to check compost quality meets Australian Standard AS4494

Soil in windrow area

An external contractor will sample the soil within the windrow area, to monitor the impact of the operation.

Three groundwater bores

An external contractor will sample water from three bores, one upstream and two downstream located in a triangular configuration, to monitor the groundwater.


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4.7 Loading trucks

Trucks are to be loaded at windrows unless the area is too soft due to weather conditions.

If windrow area too soft, compost is to be stockpiled at loading ramp to load

trucks efficiently

Drivers are to remain in the truck or the site office at all times.

A docket is to be written out and given to the driver detailing the following information:

- Company name - Date - Batch and type - Drivers name - Quantity of material taken - pH if required by customer

Be courteous at all times - the drivers are our customers or represent our

customers.

If a dispute arises immediately refer the situation to your supervisor.

Loading trucks and attending to customers is a priority over other duties.


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Section 5: Documentation

Document Purpose

Compost Plant Computer Log

Up to date records for each batch kept automatically by computer:

recipe windrow locations age and reduction factor stock levels

Compost Production Report.

The daily production figures are kept automatically by the computer. They can be accessed through the SCADA system.

Weekly Windrow Layout Report Prior to turning, take and record windrow temperatures at intervals of 50m. Indicates microbe activity.

Vehicle Maintenance Log Book Separate book for each vehicle. Record daily safety and maintenance checks on all rolling stock.

Maintenance Job Sheet (Repairs Log)

Use to record equipment problems for the attention of maintenance department.

Despatch Dockets Completed for outgoing materials. Must include batch number so that stock level records can be updated, in addition to the date, client, volume, and product type.


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Section 6 Maintenance and troubleshooting 6.1 Regular maintenance and cleaning

Equipment Action

Loader

Check the radiator and air filter are clean 3-4 times

daily to ensure efficient cooling

Remove material build-up from bucket galleries to prevent failure of cylinders and linkages.


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Batching plant During operation and after batching, visually check all moving parts for obvious defects. Report any problems to the maintenance department by completing a Maintenance Job Sheet.

Conduct routine daily cleaning of material spillage around equipment when it is safe to do so during production.

Conveyor rollers and associated structures

Clean daily to prevent build-up. Make sure the equipment is shut down and tagged out per Tag Out and Lock Out Procedure, SAF-001.

Production equipment Hose down in the normal course of operation, including the hopper loading apron. Make sure that all resulting waste water will drain to the Biological Treatment Plant.

Rolling stock Conduct daily maintenance checks and record in log book.

Maintain water and oil levels. Grease as per manufacturers specifications.

Waste oils and lubricants Collect and place in the Waste oils depository located in the Grease and Lubricants shed.


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6.2 Normal operating conditions As a competent Compost Plant operator you should know the optimum operating conditions for the equipment, so that you can recognise abnormal conditions and respond quickly with the appropriate action.

These functions can be monitored via the SCADA computer program or the blending plant control panel.

Function/Parameter Normal range Corrective action

Air pressure Above 600Kpa Check gauges at hopper 2 and mixer.

Hopper 1 Fill to maximum Add material when Ready to fill light flashes. Blending will stop.

Hopper 2 Fill to maximum Add material when Ready to fill light flashes. Blending will stop.

Sludge silo 23,000kg

(27,000kg capacity)

When silo full alarm activated, contact ETP operator immediately.

Batch time 2-10 seconds Set via Run features window or computer.

Total batch weight 1,400kg max. Set via Batching control window or computer.

Monopump pressure 2-10 bar Monopump will shutdown if pressure falls below pre-set pressure for 60 seconds.

Clean sensor and make sure hopper level at least 10%. Restart.

Windrow (initial formation)

1.7m high

5.5m wide

200-300m long

Run east/west

8.0m between centres

Reform windrow to correct size.

Windrow core temperature during maturation stage

Above 55C If temperature is low, check age, moisture and oxygen levels.

Windrow moisture 45-60% Check windrow moisture as per 4.6.


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6.3 Using the SCADA to monitor operations The SCADA screens can be used to:

display current production data (Mimics)

display graphs of equipment operation over time (Trends)

provide data on past production events/alarms. (Historical alarms) These functions are selected from the main menu screen:

The overview mimic screen

This screen displays: what product is being blended

the current levels in the hoppers and silos

the equipment set points

the daily production figures

It also allows you to enable/disable the biosludge monopump.


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The trend screens The trend screens give a graphic display of how various functions are running. Different coloured lines are used for the various functions.

The screens below show the Batch trends. The top screen shows normal operation, while the bottom screen displays a problem with mixer motor load.


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Section 7: Assessment 7.1 The assessment procedure There are two parts to the assessment of a trainee:

a checklist to monitor the progress of the trainee and assess their competence in all areas of operation.

a set of oral questions related to quality maintenance, workplace

communication, and occupational health and safety. The checklist The checklist sets out all major areas of compost plant operation and the related sub-tasks. The trainer will check off each task:

as it is explained to the trainee. as the trainee is observed in the task during normal operation (practice

without assessment). as the trainee demonstrates the task while observed by the assessor for

assessment. when the trainee has mastered all the sub-tasks and is therefore competent in

the major area of operation. when the trainee answers the oral questions to the satisfaction of the assessor.

Note: The checklist does not set out the tasks in order of teaching. The training program will determine in what order to teach the tasks, and trainers should also take advantage of situations that occur in normal daily operations (e.g. occurrence of problems and faults). Oral test This will take place in the training room and in the workplace during the training period. Sample questions are included in section 7.3 of this manual.


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7.2 Checklist of operator tasks Compost Plant Major tasks/areas of operation Individual skills/sub-tasks Ta

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Explain composting process

Identify plant equipment and describe function

Explain general safety procedures and PPE

Identify hazards of compost plant and equipment

Operate loader safely (to above 4m height)

Carry out vehicle pre-operation checks

Operate windrow turner safely

Operate tractor and bucket safely

Operate forklift safely

Start up and shut down blending plant

Enter batching program settings

Operate sludge collection system

Interpret SCADA screens

Construct windrows

Turn and water windrows

Take windrow temperatures

Survey windrow stock levels

Carry out pH test

Carry out moisture level test

Maintain production records for each batch

Complete sales dockets accurately

Clean and maintain batching plant

Clean and maintain vehicles

Clean and maintain windrow area

Your trainer will initial each item on the checklist as you go through your training program. You can then keep track of what you know, and what you still have to learn.

Note that you will not necessarily learn things in this order.


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7.3 Oral questions Compost Plant operator These are questions that a workplace assessor might ask you in order to assess your competence as a compost plant operator. Explain the function of the Compost Plant by answering questions 1 to 3.

1. What goes into the compost, and where does this material come from?

2. How long does it take for the compost to mature?

3. What are the essential elements for the thermophilic process? Describe the major duties of the compost plant operator by answering questions 4 to 7

4. What materials handling is the operator required to do? What equipment is used, and what are the hazards the operator needs to consider?

5. List each item of documentation the operator has to complete (paper and electronic), and its purpose.

6. List the people with whom the operator has to communicate, and the type of information communicated.

7. Describe the main operator duties involved in running the compost plant, including:

a) Starting up the blending plant

b) Operating the sludge collection system

c) Constructing windrows

d) Maintaining windrows to optimise composting process

e) Surveying windrow stock levels

f) Cleaning and maintaining vehicles Explain the safety procedures to be followed in the compost plant by answering questions 8 to 10.

8. What is the vehicle speed limit in the compost area, and why is this necessary?

9. What personal protective equipment must be used, and why are these items important?

10. Explain the Lock out/Tag out procedure, and when it is used.

2.07 GWC Compost Manual

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