PRODUCTION EFFICIENCY/ POLLUTION PREVENTION FACTORY ...siteresources.worldbank.org/INTBANGLADESH/... · POLLUTION PREVENTION FACTORY ASSESSMENTS 2. The main findings Metering Starting

গণপ্রজা তন্ত্রী বা ংলা দে শ

PEOPLE’S REPUBLIC OF BANGLADESH

PRODUCTION EFFICIENCY/ POLLUTION PREVENTION FACTORY

ASSESSMENTS FOR FABRIC MILLS AND DYE HOUSES IN BANGLADESH

Dhaka, 8 May 2011

POLLUTION PREVENTION FACTORY ASSESSMENTS

Summary

1. The approach2. The main findings3. « Low hanging fruits » measures4. « Best of the best » measures


1. The approach

Objectives

• Identify measures to reduce the use of energy, water and raw materials

• Identify the factors that will contribute to scaling up


1. The approach

Criteria• 4R: Reduce, Reuse, Recycle and Recover

PROCESS STAGES


1. The approach

CriteriaScaling up based on economic benefits

• as perceived by the factory• Direct benefits: savings• Indirect benefits: marketing


1. The approach

1. Low hanging fruits :• Feasible• Cheap (< 500,000 TK) or very cheap• Payback period shorter than 1 year


1. The approach

2. Medium hanging fruits• Feasible• Payback period higher than 1 year

3. Higher hanging fruits• Needs further study• Not so cheap• Payback period higher than 1 year


1. The approach

Methodology: 4 tasks

A. Case studies of Top Performing Factories B. Assessment of five Medium-Performing FactoriesC. Support the implementation in one factory. D. Consolidation and final report


2. The main findings

N° Best Practices Class. Process stage Location Yes No

WATER 1/3 2/3

W1 Eliminate water leaks in taps and pipes Low Several Upstream 5/7 2/7

W2Reuse water drained out of steam condensates Low Dyeing Downstream 4/7 3/7

W3Minimize washing and rinsing (over flow) operations Low Several Upstream 3/7 4/7

W4Reuse of first wash water from solution preparation tanks Low Dyeing Downstream 0% 100%

W5Restrain hose pipe use and create a cut sample washing basin/place. Low Several Upstream 3/7 4/7

W6 Reuse cooling water Medium Several Downstream 4/7 3/7

W7

Reuse wastewater from processes in other processes that do not require high quality water. Medium Several Downstream 0% 100%

W8 Fabric to water ratio to 1:6 Study Dyeing Upstream 1/7 6/7




ENERGY 1/3 2/3

E1Maintain steam traps and optimized steam management Low Dyeing Upstream 3/7 4/7

E2 Insulate pipe line, valves and flanges Low Dyeing Upstream 6/7 1/7

E3Optimize operation of air compressors and chilling plants Low Several Upstream 2/7 5/7

E4Save lightening energy using transparent roofs Low Several Upstream 2/7 5/7

E5Use of good squeezing operation to reduce energy at drying stage Low Drying Upstream 100% 0%

E6 Recovery of heat from drying operations Medium DryingDownstream 0% 100%Use of direct drying system Drying Upstream 6/7 1/7

E8 Automatic boiler blow down mechanism Study Utility area Upstream 2/7 5/7

E9Recover energy from high temperature process for wash water heating Study DyeingDownstream 1/7 6/7

E10Recovery of heat from gas generation vent Study SeveralDownstream 1/7 6/7

E11Use co-generation plant instead of two separate generators plus steam boiler Study Several Upstream 0% 100%




PRODUCTS AND CHEMICALS 1/3 2/3

C1 Reduce spillage of chemicals Low Dyeing Upstream 3/7 4/7

C2

Optimize correct temperature and volume to reduce salt, auxiliary and dye consumption. Low Dyeing Upstream 100% 0%

C3Collection of surplus printing paste and using the same as black paint Low PrintingDownstream 1/1 0

C4Use of magnetic device for water softening Low Several Upstream 1/7 6/7

C5Repeated reusing of caustic solution in the mercerizing operation Study MercerizingDownstream 1/2 1/2

C6 Recover of sodium sulfate Study DyeingDownstream 0% 100%




TRANSVERSAL ISSUES 2/5 3/5

T1Improved process control stages to avoid reprocessing, re-dyeing etc. Low Several Upstream 100% 0%

T2Improve recipe of dyes in laboratory automated / robotic dispensing system Low Laboratory Upstream 2/7 5/7

T3Sufficient number of solution preparation vessels Medium Dyeing Upstream 5/7 2/7

T4Use dry cleanup methods like vacuum, brooms, absorbents etc. Study Drying Upstream 0% 100%

T5Explore recovery of size in cotton processing Study MercerizingDownstream 0% 100%

Total 1/3 2/3



Saving on water?• Water is considered almost free• Expensive treatment plants• Savings through other sectors (energy, chemicals)



Saving on energy?• Insolation• Reuse (energy and water)• Optimize



Saving on chemicals?• Management, laboratory trials• Reduce spillage• Reuse



MeteringStarting metering can be done first at the factory level then to the unit inlets and at the end to the machine sites.

Cost of water flow meter:Electromagnetic type: BDT 3,00,000-5,00,000/=Mechanical type: BDT 50,000- 1,00,000/=

Cost of steam flow meter: BDT 10,00,000/=

At bore wellsAt unit siteIn the machine 2/3At bore wells 100%At unit siteIn the machine 2/3

At gas generators site 100%At unit siteIn the machineAt gas generators site 100%At unit siteIn the machine

At receiving sites 100%At unit siteIn the machineAt receiving sites 100%At unit siteIn the machine

Existing water meters?

Existing power meters?

Existing gas meters?


3. “low hanging fruits” measures

« Low hanging fruits » practices

• Feasible• Cheap (< 500,000 TK) or very cheap• Payback period shorter than 1 year



Measure n°W1 : Eliminate water leaks in taps and pipesSector: WaterSub-sector: Water consumption/waste water generation

Present situation :There are several leakages of water from taps, valves and pipes in the factories. Machine leaks were also visible in some places. In few machines the taps over the preparation tanks were designed in a way that even after leak the leaked water was falling inside the tanks.

Potential saving:Cost of water: Tens of thousand TK/yearCost of waste water:Tens of thousand TK/year

Future situation (improved):Repair and maintain taps and pipes .Leakages are eliminated through leak detection measures,preventive maintenance and improved cleaning.Savings may not be lucrative but it will keep the premiseclean and dry.

Investment Cost: negligibleFuture operation cost: negligibleSaving: Tens of thousand TK /yearPayback period: immediate

Priority : Low hanging fruit



Measure n°W2 : Reuse water drained out of steam condensates

Sector: Water and energySub-sector: DyeingPresent situation:Steam is used directly as well as indirectlyin the dyeing department. During indirectuse, steam gets converted to water. Thisis pure water that still retains some heat.At several places it is collected anddiverted as boiler feed water. However,not all such steam is being reused. Someof the assessed factories hasimplemented it and recovering 50-60% ofcondensate to reuse in the boiler feed.

Potential saving:Cost of water:Hundreds of thousand TK/yearCost of wastewater treatment:Hundreds of thousand TK/year

Future situation (improved):Collect all steam condensate and divert to boiler feed water.

Investment Cost: tens of thousand TKFuture operation cost: negligibleSaving: Hundreds of thousand TK/yearPayback period: months months




Measure n°W3 : Minimize washing and rinsing (overflow) operationsSector: WaterSub-sector: Wastewater managementPresent situation:In each batch process, the factory isdoing cycles of operations includingseveral washing and rinsingoperations. As per best practice onlyfew washes and rinses are sufficient.For medium performing factoriesaverage water used per kg of fabric(knit cotton) is 180-220 Liter; 60-100liter of which is being used inoverflow rinses only.

Potential saving:Cost of water: millions TK/yearCost of waste water: millions TK/year

Future situation (improved):The factory will implement a new practice where washing andrinsing cycles will be stopped once the effluent is color free.Reducing the number of cycles will reduce the waterconsumption. A controlled overflow rinse can reduce the wateruse using the existing machinery.

Investment Cost: negligible

Future operation cost: Negligible

Saving: millions TK/year

Payback period: immediate




Measure n°W4 : Reuse of the first wash water from solution preparation tanksSector: WaterSub-sector: Water consumption and wastewater

Present situation:Dye solution is prepared (mixed) in one dedicated vesselin the dye kitchen. Before preparing a second colorsolution in the vessel, the vessel is cleaned with freshwater. This water is currently treated as waste anddrained to the ETP.Dye/chemical dosing tanks with the machine contains some dyes/chemical after dosing. That cleaning water is being thrown away.

Potential saving:Cost of water: tens of thousand TK/yearCost of waste water: tens of thousand TK/year

Future situation (improved):Dye solution will still be prepared in one dedicatedvessel. However, the water used to wash the vessel inbetween two dye solutions will not drain to ETP, but willbe taken back in the dye solution for use. Thedye/chemical dosing tanks cleaning water also needs tobe sent back to the machine.Savings in water may not be lucrative but willincrease accuracy in the process.

Investment Cost: negligible: only training

Future operation cost: negligible

Saving: hundreds of thousand TK/year

Payback period: Immediate




Measure n°W5: Restrain hose pipe use and create a central cut sample washing place.

Sector: WaterSub-sector: DyeingPresent situation:In process equipments, the water is filled in closed conditions and no overflow of water is taking place from machines. However, water is used without any restriction with hose pipe for floor cleaning, cleaning of vessels, washing of small dyes fabrics etc.In each machine a tank of water is being boiled (during dyeing) for long time to use for washing cut sample to check shade/quality.

Potential saving:Cost of water:Tens of thousand TK/yearCost of waste water treatment: tens of thousand TK/year.

Future situation (improved):Evaluate requirement of hose pipes: maybe they are not needed at all.Possibly they can altogether eliminate hose pipes. Only one wash basinin the dyeing area will serve the purpose.


Future operation cost: negligibleSaving:Total: tens of thousand TK/yearPayback period: Immediate




Measure n°E2 : Insulate steam pipesSector: EnergySub-sector: Dyeing

Present situation:Proper insulation can save energy. The non-insulated portion can release energy inatmosphere.

Potential saving:Heat loss from uninsulated portionhundred of thousandTK/year

Future situation (improved):Remaining portion of pipes will be insulated.

Investment Cost:Tens of thousand TK

Future operation cost:Negligible

Saving: hundred of thousandTK/year

Payback period: months




Measure n°E3 : Optimize operation of air compressorsand chilling plantsSector: EnergySub-sector: Utility section

Present situation:The required air pressure in the line is 3to 4 bar, while the factory is producingthe compressed air at 7 to 8 barpressure. There is no leakage in airlines and no excess use of compressedair.

Potential saving:Cost of energy: 20% of energy at air compressor could be saved.Total: hundreds of thousand TK/year

Future situation (improved):Compressed air will be produced at lower pressure, savingenergy.

Investment Cost: Negligible


Saving: : hundreds of thousandTK/yearPayback period: Immediate




Measure n° E4 : Use transparent roofsSector: EnergySub-sector: Electricity consumption

Present situation:Tube lights in dyeing unit. Each willconsume 40 watt.

Potential saving:Cost of electricity in day time:Cost of :tens of thousand TK/year

Future situation (improved):Replace asbestos roofs with FRP transparent roof. So during daytime, tube lights will be switched off.

Investment Cost: tens of thousand TKFuture operation cost: Reduced

Saving: tens of thousand TK/year

Payback period: depending on size.




Measure n°C1 : Reduce spillage of chemicalsSector: ChemicalsSub-sector: Consumption of chemicals and wastewater

Present situation:Sodium sulfate, soda ash and caustic sodaconsumption is thousands of kg per day. Itis handled in bags that are brought to thedyeing area and manually transferred to thesolution making tank. During the transfersome spillages take place. The chemical iseventually washed away with water comingfrom hose pipe and ends up into the .

Potential saving:Cost of chemical spillage:tens of thousand TK/year

Future situation (improved):The factory reduces spillage and washing into wastewater.

Investment Cost: negligibletraining only

Future operation cost: negligibleSaving: tens of thousandTK/yearPayback period: immediate




Measure n°C4 : Use of magnetic device for soft water in boiler.Sector: ChemicalsSub-sector: Pretreatment of water

Present situation:The factory has a water softening plant. Even after the watersoftening treatment, however, the water still has some residualhardness. Continuous chemical dosing is done to make boilerinlet water hardness free to avoid scales in the surface of theboiler.

Potential saving:Hundreds of thousand TK/year

Future situation (improved):To take care of residual hardness, a magnetic watersoftening device can be installed in the boiler inlet. Thiswill keep the metal cations oriented. The device will helpprevent the formation of a white calcium and magnesiumcarbonate scaling, and thus make sure the whole capacityof the boiler is available. The final result is an increase inefficiency and reduced frequency of boiler de-scaling.

Investment Cost:Hundreds of thousand

Future operation cost: Reduced

Saving: Hundreds of thousand TK/year

Payback period: 6 to 12 months



4. "Best of the best" measures

« Best of the best » practices

• innovative• cost effective• representative and replicable



Measure n°W8 : Increase fabric to water ratio to 1:6Sector: WaterSub-sector: Water consumption

Present situation:Fabric to water ratio is 1:8. There is scope for improvement.Modern machines allow ratio like 1:3. By using the existingmachines conservation can be approached to reach close to1:6.

Potential saving:Water and cost :millions TK/yearChemical cost :millions TK/year

Future situation (improved):Smooth running of the fabric inside the machine requirementsin reducing water in the vessels. Optimize processes andrecipes in order to reduce water and chemicals consumption.Even if machine replacement needed, it can be thoughtduring BMRE of the existing high water consumingmachines. The benefits of W3 will be added in thepotential savings to make the investment feasible.Fabric to water ratio is increased to 1:6

Investment Cost: millions of TK


Saving: Tens of millions TK/year

Priority : Medium Hanging Fruit



Measure n°E1 : Maintenance of steam traps (Proper steam management)Sector: EnergySub-sector: DyeingPresent situation:The function of a steam trap is to allow the condensedsteam in the pipe line to drain out and prevent it fromescaping into the air. If the trap is not maintainedproperly, steam will be lost. There are factories whereat a place of the steam line valve/trap is kept opento reduce control in the steam management and toavoid jerking. Proper steam trap and steam supplymanagement will reduce that. It is also possible torecollect that steam/steam condensate to heat upremaining raw water inlet of the boiler.

Potentialsaving:Cost of steamloss:Several millionsTK/year

Future situation (improved):Carry out regular maintenance of steam traps and ensure that traps areof adequate size. This will prevent the loss of steam and save water andenergy.


Future operation cost: negligibleSaving: Several millions TK/yearPayback period: immediate




Measure n°E8: Automatic boiler blow down mechanismSector: Energy Sub-sector: Consumption of gasPresent situation:Blow down operationis carried out basedon a generalprinciple.

Potential saving:If blow down is more than required, itmeans that extra water is being consumedand heat is being lost. If blow down is lessthan required, means there will be morescale formation in boiler, more energyconsumption and decreased life of boiler.

Future situation (improved):Regular and appropriate blow down mechanism according tocontent. Measure the Total Dissolved Solids of blow down waterand optimize blow down operation accordingly.This measure will help the factory either in water consumption orfuel efficiency, and increased boiler life duration.

Investment Cost: Cost of meter only. If manual meter is provided, it will cost only 5000 TK, if fully automatic blow down system is installed, it will cost 100,000 TK per boiler.


Saving: Could be calculated only after actual measurement of level.Payback period: Require further study



Measure n°C4 : Use of magnetic device for soft water in boiler.Sector: ChemicalsSub-sector: Pretreatment of water

Present situation:The factory has a water softening plant. Even after the watersoftening treatment, however, the water still has some residualhardness. Continuous chemical dosing is done to make boilerinlet water hardness free to avoid scales in the surface of theboiler.

Potential saving:Hundreds of thousand TK/year

Future situation (improved):To take care of residual hardness, a magnetic watersoftening device can be installed in the boiler inlet. Thiswill keep the metal cations oriented. The device will helpprevent the formation of a white calcium and magnesiumcarbonate scaling, and thus make sure the whole capacityof the boiler is available. The final result is an increase inefficiency and reduced frequency of boiler de-scalling.

Investment Cost:Hundreds of thousand


Saving: Hundreds of thousand TK/year

Payback period: 6 to 12 months




Measure n° C6 : Recovery of sodium sulfateSector: ChemicalsSub-sector: Consumption of water/quality of wastewaterPresent situation:Reactive dyes are used for cotton dyeing. Sodium Sulfate- popularly known as Glauber salt is used for transferring dye from solution to fiber. The entire quantity of sodium sulfate is presently going to the ETP since it is not consumed by the Fabric. This high quantity of sodium sulfate gives a relatively high Total Dissolves Solids (TDS) concentration in the effluent. To take the effluent discharge within the permissible level in terms of TDS, factories allowing diluting of the waste water as existing ETP’s can not reduce TDS.

Present cost:Cost of sodium sulfate is 12,000 TK/ton.Present cost is tens of millions TK/year.

Future situation (improved):Segregate dye solution containing sodium sulfate: there aretechnologies available to recover sodium sulfate from effluent.They are technically viable and economically feasible. Thetechnology is based on the Multi Effect Evaporator (MEE)principle.This is the way Bangladeshi textile industries can moveforward to zero discharge as it will reduce TDS (onlyproblem of existing ETP discharge to be reused in theprocess) to a reusable level.

Investment Cost: tens of millions TK.

Future operation cost:

Savings:Around 70% of the initial sodium sulfatecost will be recovered.tens of millions TK/year.Payback period: Payback period isestimated around two years.



Measure n°T1 : Improve process control stages to avoid reprocessingSector: Transversal issuesSub-sector: Process controlling

Present situation:Existing: the reprocessing is similar to the one applied in theTOP performing factories. Overall reprocessing percentagein Bangladeshi industries has reduced. But in the mid levelindustries still a significant improvement can be done.

Potential saving:Several millions TK/year

Future situation (improved):Mainly a combination of managerial and technicalcontrol. Quality assurance of the raw material (mainlydyes & chemical), Establishing and maintaining RightFirst Time (RFT) in the process and Quick Response inthe management will reduce reprocessing.

Investment Cost: negligible (staff training)

Future operation cost:

Saving:Several millions TK/year

Payback period: immediate




Measure n°T2 : Improve trial recipe in laboratorySector: Transversal issuesSub-sector: Water/chemical

Present situation:Manual recipe pipetting and preparation. Efficiency is reducedand will affect the bulk production accuracy. Most of thefactories has spectrophotometer for color measurement andspeculating recipe. But human error during pipetting resultsreduced efficiency of the lab.

Potential saving:Several millions TK/year

Future situation (improved):Setting up robotic auto dispensing machine or electronicpipetting devices. Proper calibration and updating of labequipments (spectrophotometer). These will contribute inhigher laboratory efficiency and production and also itwill reduce reprocessing percentage.

Investment Cost: cost of robotic auto dispensing machine or cost of electronic pipettes.Future operation cost: very low, reduced man power needs

Saving: Several millions TK/year

Payback period: 1 to 2 years



www.ecopsis.com/documents/PPT


THANK YOU FOR YOUR ATTENTION

Documents

PRODUCTION EFFICIENCY/ POLLUTION PREVENTION FACTORY ...siteresources.worldbank.org/INTBANGLADESH/... · POLLUTION PREVENTION FACTORY ASSESSMENTS 2. The main findings Metering Starting