Presentation on theme: "Efficient Uses of Steam Energy in Textiles to Reduce Cost & Improve Productivity 2nd International Conference on Textile & Apparel, ICTA-2012."— Presentation transcript:
1 Efficient Uses of Steam Energy in Textiles to Reduce Cost & Improve Productivity 2nd International Conference on Textile & Apparel, ICTA-2012
2 What We Do?Forbes Marshall is an ISO 9001 company specializing in the Field of Steam Engineering & Control InstrumentationWe are working with steam for last 106 years and have our manufacturing facility in India and others in joint venture with Spirax Sarco, ARCA, Krohne, Codel & Vynce.We manufacture Steam Boiler (NG/Diesel/Solid fuel fired), Exhaust Gas Boiler and almost all the steam system accessories.
5 Energy AuditForbes Marshall has an Energy Audit division having expertise in specific fields.Forbes Marshall has conducted over 100 detailed energy audits across the industry covering each and every process including dyeing units, washing units, denim plants etc.In each of our audits we identified the opportunity for savings ranging from 20% to 30%.Successful implementation of our audit recommendations of these plants has yielded significant improvements in Specific Fuel Consumption (SFC).
6 Why Steam?Fuel used for generating steam accounts for about 50% of total utility cost.Scarcity of Natural Gas, increase in cost of fuel and hence the steam costsEffective steam management plays a role inFuel Savings - which can be leveraged for cost competitiveness . Reducing fuel cost is the only route to cut costs substantially.Product Quality – Maintaining proper steam parameters ensures product quality, e.g. uniform colour, print, brightness etc.Productivity -Improving batch timings on equipment.
7 Benchmarking where do we stand ? Forbes Marshall studies of over 60 textile plants reveal differences in fuel consumption within the industry.39% difference in Specific Fuel Consumption (SFC) between the best and average plants.The worst plant consumes more than 3 times the amount of fuel as compared to the best plant.
8 Why is the best plant the best ? Differences in Specific Fuel Consumption (SFC) across plants on account of:Efficient steam generationOptimized steam distribution & utilizationRecovering condensate & flash steamProper steam trapping
9 Comparative Study Capacity (Kg) Ideal Steam Consumption with Right Steam and condensate loop (Without Heat Recovery/With Heat Recovery* (Kg/Batch)Actual Steam consumption (Kg/Batch)Required Steam Pressure (Barg)Actual Steam Pressure (Barg)Batch time (mins)Max Gradient (°C/min)LightMediumDark250461/281559/379641/4615276607693.56-75400660/460711/511770/570782839890600863/5631227/9271698/1398907132619507501358/7581817/12171922/132215851980216015002227/13772490/16402769/1919253129823187
10 Not using PRV before Process machine Common issues found because of not adopting right steam engineering practices-Not getting right pressure & temperature in the m/cBatch time goes high and product quality hamperedProper steam trapping is not in practiceRunning boiler at lower pressureNot using PRV before Process machineNot using temperature controlMany of the time traps are bypassedSteam distribution system is not properSteam mains are oversized or undersizedTraps and valves leakageInsulation of Steam & Condensate line is not properNot recovering condensate & flash steamFeed water temperature is ambientBoiler blowdown is manual
11 Valve LeakageA 1/8 inch hole in steam main can waste 15 tons of coal or 9 tons of fuel oil per year.
12 A leaking 25 NB Thermodynamic Trap on a 7 bar line will lose steam at the rate of 18 kg/hr. This translates to a loss of more than 150 Tons of steam annually.
21 The Steam and Condensate Loop Distribution losses 5-7%85%BoilerProcess100% Input60% Process useBoiler losses %20% CondensateSo, for 1 Ton steam for process, fuel used equal to 1.67 Ton
22 Steam use in process – 60%Different losses – 40%
23 Steam GenerationTwo things are directly effect boiler steam generation –Boiler operating pressure & Feed water temperaturePoor boiler efficiency due to-Fluctuating loads – improper loading on the boiler which can be addressed by proper boiler selection, capacity, burner turndown, etc.Absence of diagnostics to take corrective action – same can be addressed by steam and oil flow metering, stack monitoring with boiler load management and online efficiency check.Manual Blow down - because of over blow down losses of money and less blow down increases the risk of boiler life.
31 ConclusionFuelScope for savings (%)Gas11.2 %Liquid11.8 %Solid17.1 %No Matter which fuel type you look at, the scope of savings is 10 % to 15 % at least.No boiler is an exception
32 Steam DistributionHigh distribution loss across plants on account of -Improper line sizingImproper insulationImproper line routing & condensate removal from steam linesThese losses can be addressed by -Proper design of the distribution network, i.e.; proper line sizing without extra provisions for expansionsProper insulation and efficiency checking mechanismProper condensate removal from steam linesDiagnostics – pressure and temperature gauges, steam flow meters, etc.
33 Distribute Steam at High Pressure This will have the following advantages:Smaller bore steam pipes needed and therefore less heat (energy) loss due to the smaller surface area.Lower capital cost of steam mains, both materials such as pipes, flanges and support work and labour.Lower capital cost of insulation (lagging).The boiler can be operated at the higher pressure corresponding to its optimum operating condition, thereby operating more efficiently.The thermal storage capacity of the boiler is increased, helping it to cope more efficiently with fluctuating loads, and a reduced risk of priming and carryover
34 Pipe Sizing Greater Cost Greater Heat Loss Greater Volume of Condensate FormedLower Pressure to Steam UsersNot Enough Volume of SteamWater Hammer and Erosion
35 Slug of water from condensate WaterhammerSagging MainCondensateSlug of water from condensateVibration and noise caused by waterhammer
36 Relaying to Higher Level Fall 1/250SteamRelayto highlevelmDrain PointsSteam Flow Flow
39 Drainage of Condensate from Steam Line Steam FlowSeparator
40 Importance of Moisture Separator Fig. Temperature profile across a heat exchange surface
41 Steam Utilization Steam Trapping - In most plants, trap selection is an issue on heating applications.Group trapping on equipment also needs to be addressed.Across textile plant audits and surveys we have conducted we find that only 50% of the installed traps are OK.
42 TD Traps are used in Process, it should be float trap Disadvantages of TD:-Intermittent discharge.-Condensates not removed properly, get water logged.Increase steam consumption by 8~10%Increase process timeBy 25~30%
43 Ball Float Trap: Ensures proper removal of condensate from the process as soon as it forms. Recommended for process application.
44 Condensate & Flash Steam Recovery Huge gap between quantum of condensate being recovered and potential for recovery observed across all plants.Across many plants, boiler feed water temperature is ambient and condensate is being drained.In plants where condensate is recovered, it is doing using an electrical pump leading to loss of useful heat.Flash steam is normally not recovered and is vented. Flash steam can be recovered and used for feed water heating.
45 This calculation is made for diesel fired boiler * This calculation is made for diesel fired boiler Similarly it can be done for gas fired boiler.
46 Multiple Benefits of Condensate Recovery Condensate water contains 20% energy of steam. Returning condensate improves the feed water temperature and thus lowers fuel bill.Returning condensate to feed water tank cuts the makeup water requirements.The condensate returned does not need to undergo water treatment and thus saving treatment cost.It has no TDS. It reduces the requirement of blowdown thereby curtailing blowdown losses.Reduce the cost for oxygen scavenging chemicals, since the improved temperature will reduce the amount of dissolve oxygen almost 75%.
47 Multiple Benefits of Condensate Recovery Higher feed water temperature by recovering condensate increases the boiler output with reduced fuel consumption.Recovering flash steam is as important as recovering condensate water. Flash steam contains 50% energy of the total recovered condensate, although it may be 10~15% in mass.[Please Note: Holding condensate in collection tanks reduces the condensate temperature via radiation losses. Condensate should be returned as soon as it formed. ]Every 60C rise in the feed water temperature by using condensate water & flash steam gives 1% saving in fuel.
50 Energy Content in Dye Liquor Not considering losses the Process Heat Recovery in Dyeing m/c45 %15 %Dye Bath LiquorCooling WaterEnergy Content
51 Benefits of Dye Liquor Heat Recovery Recover heat from dye liquor 60~80 deg C from the dyeing machine. Savings up to 15% in steam used for hot water preparation.Pre-heats process water to the dyeing machine. 1-2 extra batches per week possible.Facilities low temperature discharge to ETP. Helpful for effluent treatment.Eliminates pressure fluctuation of boiler.
53 Enconomy opportunities Trap ManagementSelection of right TrapBypassLeakageStop LeakagesInsulationCondensate RecoveryFlash Steam RecoveryStop Blowdown LossesFeedwater tank ManagementStop Waste (12-15%)
54 Encon opportunities Steam Flowmetering Dye Liquore Heat Recovery Efficiency OptimisationLiquor ratio controlSteam Pressure ControlTemperature ControlInstant Hot water supplyDryness of SteamCapacity UtilisationOptimization ( 8-10%)Waste Management
55 Encon Opportunities Boiler Efficiency Monitoring Waste Heat Recovery Boiler from GeneratorThermic Fluid Generator-Efficiency % optimisationHot water from DG set JacketOptimizationWaste ManagementHeat Recovery (7-8%)
56 Our recommendations which included – Optimized steam generationImproved steam distribution systemProper selection and sizing of steam trapsBetter management of the process like installing temprature & pressure controlsUtilizing waste heat recoveryRecovering condensate with flash steam to improve the boiler performance
57 Forbes Marshall has a Consultancy Division worked for the project design and consultancy for steam, water & air distribution system to make the industry energy efficient and sustainable. Forbes Marshall has done Consultancy in many industries of Bangladesh. Few of them are, Hameem Denim, DBL, Ecotex, GMS composite, Graphics Textils, etc.Copyright Forbes Marshall,
58 One of Many Successes in Bangladesh!! Industry Knit ConcernLocation NarayangongSteam Usage Fabric Dyeing, Finishing & GarmentsFuel GasCuttingCostsDownBefore Energy Audit -They have a requirement of 3~4 TPH boilerTheir machine was starving for steamAfter Energy Audit & Implementing Recommendations –Till now they have no shortage of steam and no requirement of steam boilerReason found :Wastage and leakage of steam in different pointsCondensate was not recoveredBoiler was running under pressureToo much blowdown lossesLive steam wastages from garments section.Copyright Forbes Marshall,
59 0.28 Kg Wood/ Mt Cloth (Rs0.58/MtCloth)!! One of Many Successes!Industry Textile Processing UnitLocation Madhya PradeshSteam Usage In Process eqpt – Stenters, Back filling M/cs, Calendar M/c etcFuel WoodCuttingCostsDownThe objective - Improve SPFC from 0.33 kgs wood/mt cloth (Rs 0.66/ mt cloth).Energy conservation recommendations implemented by customeroptimized fuel management – sizing.Optimized steam generationundertook better management of process like temp control.optimized waste heat recoveryreduced losses on account of inappropriate / in-operational trappingThe Results?The SPFC came down to0.28 Kg Wood/ Mt Cloth (Rs0.58/MtCloth)!!Copyright Forbes Marshall,
60 Customer Saves Rs 30 Lakhs/year!! One of Many Successes!Industry Textile Processing UnitLocation GujaratSteam Usage Yarn Dyeing M/csFuel HSDCuttingCostsDownThe objective – Reduce Fuel ConsumptionEnergy conservation recommendations implemented by customerOptimized steam generationReduced losses in steam distribution circuitundertook better management of process like temp control.optimized waste heat recovery – dye liquor, condensate & flash recovery.reduced losses on account of inappropriate / in-operational trappingThe Results?BeforeAfter AuditFuel Consumption (lts/day)1,150820Costs (Rs/day)17,2509,020Customer Saves Rs 30 Lakhs/year!!
63 Find out where you stand!!! Fuel prices would continue to spiral upwards……. & so would your losses!The longer you wait…..The more your losses accumulate!Find out where you stand!!!Get a free scoping study done by FM Experts