Pollution and Pollution     Control Performance and        Measures in India                  COKE OVENS              Refe...
Coke Ovens is complex       of distinct plants             Coke Oven, By Product            Plant, Effluent Treatment     ...
Presentation of CSE        Report, June 2012 on          the Iron and Steel           Industry in India                   ...
Presentation I  COKE OVENSSunday, November                   418, 2012
There is a variant to this    complex in the form of                  Coke oven heat               recovery/non recovery  ...
India has 32 million tonnes    of annual coke producing             capacity                   Of this 23 mtpa is the by p...
The basic processes are• Coal is heated in Coke Oven in the  absence of air to yield coke.• Volatile matters wholly and pa...
Three Basic Processes                   Coke Oven Gas                   to by products.       Effluent  Coal to coke.     ...
Pollution From Coke                 Ovens                                   Coal                       CO Gas             ...
23 million tonnes of annual capacity  COKE OVEN BY PRODUCT  RECOVERY TYPESunday, November                                 ...
Kinds of PollutionDue to combustion of     Due to incompletecoal                     combustion                         • ...
Kinds of Pollution ..Fugitive                  Process• Unintended waste        • Generated out of  due to leakages.      ...
Kinds of pollution ..• Air• Water• Solid sludge.Sunday, November                                  1318, 2012
Usually air emissions.  POLLUTION IN COKE  OVENSSunday, November                           1418, 2012
Sources of Pollution in           Coke Ovens1. Splutter when coal is placed in the   heated oven, called charging emission...
Charging emissions can be      prevented by• Increasing compactness in coal  packing. Change from top  charging to stamp c...
Diffuse emission can be         prevented by• Using self sealing doors.• Use of magnetic lid.• Use of screw tightened pipe...
Combustion emission due to under firing of stack can be    contained through• Arrest of dust containing  PM, So2, Nox, CO ...
When coke is done, and is pushed out of the oven into container cars on rails, soot    can be controlled by• Having a land...
Quenching emissions• When water is sprayed on CO Gas  to cool the fluid, water  evaporates producing steam. The  steam con...
Emissions are of two                kindsFugitive                  Process• Fugitive emissions      • Usually wholly  happ...
The emissions from CO      Plant is air emission• We track particulate  matter, So2, CO and Nox.• We track the concentrati...
Ministry of Environment andForests have specifications             for• Emission norms and standards.• Plant design equipm...
Comparison of Air Emission Standards For Coke Oven Recovery             Fugitive Visible Emissions           Units        ...
Norms Provided by the GSR 46(E) Notification dated 3.2.2006                                                               ...
(a) air-cooled self-sealing doors;                   (b)         the hydro-jet cleaning                   system shall be ...
Among the pollution control   equipment it specifies• Land based stationary  precipitator.• Norms for the use of effluent ...
Poor environment management also means poor  economic efficiency  COKE OVEN PERFORMANCE  PARAMETERSSunday, November 18,   ...
Fugitive Emission Standards Compliance Status 2009-10                                                                Compl...
Coke Oven Stack PM EmissionsCoke Oven StackParticulate Matter              2008-09 and 2009-10Emission                    ...
Coke Oven Gas                Coke Oven Stack PM EmissionsEmissions                             2008-09 and 2009-10High emi...
BF to Gross CokeYield                                 Company wise BF Coke Yield to Gross Coke                            ...
Gross Coke YieldImproves                                   Company wise Gross Coke Yield 2009-10                          ...
Coke Oven GasCollection Rate                                 Company wise Coke Oven Gas Collection Rate 2009-10Would impro...
Specific Thermal Energy ConsumptionSpecific Thermal                                   2009-10Efficiency                   ...
List of Clean Technologies1. Increase in coke oven chamber   height.2. Move over from top to stamp   charging to increase ...
Technology #1  Increase in Chamber Height• This increases the volume of the  oven and reduces the need to  repeatedly open...
Technology # 2                 Stamp Charging• Top charging accommodates 765  kgs/m3 volume. Stamp charging  accommodates ...
Technology #3               Self sealed Doors• Gas pressure is kept at a  minimum inside the oven so that  tar sealing gas...
Technology #4                    Magnetic Lid• In order to minimise  leakage/diffuse emissions,  magnetic lids are prescri...
Technology #5               Hydrojet Cleaners       Technology # 6Water sealed ascension pipes• Hydrojet cleaners helps cl...
Technology #7             High Pressure Liquid             Ammonia Aspirator• This helps capture emission by  reducing the...
Technology #8     Land Based Stationary Air              Filter• Coke is pushed out in container  cars on rails equipped w...
Design of Coke Ovens In               India                            Gross Coke                                         ...
Technologies Adopted in      Indian Coke OvensSunday, November 18,                             452012
Sulphur is removed, by products are retrieved  BY PRODUCT PLANTSunday, November 18,                                       ...
New technologies for          sulphur removal• Sulphur content in CO Gas prior  to treatment is 1800-4000  mg/Nm3.• In amm...
Sources of Pollution in By      Product Plant• Water is generated when the CO  gas condenses.• Water may contain PAH.• Wat...
Here waste water enters for treatment and cleaning.  Also sludge from distilled by products are cleaned into  non hazardou...
Steps in Effluent                Treatment Plant1.     Tar is removed.2.     Suspended solids captured.3.     BOD,COD remo...
Water Treatment                    Parameters in ETP                               Waste Water Treatment Plant ParametersP...
Water Consumption in           Coke Oven• Coke Ovens consume 13% of all  water required in the steel plants.• Water is use...
Dry Quenching reduces         water consumption.                                             Waste Water in ETP      2009-...
Solid waste can beNon hazardous          Hazardous1. Coal dust as        1. Tar decanter   spillage from          sludge f...
Hazardous Solid Waste      Generation and Disposal c                                   Hazardous Solid Waste Disposal in 2...
Overall Performance of CokeOvens, By Product Recovery•   Vizag Steel 3 leaves•   Tata Steel 2 leaves•   JSW 2 leaves•   Ne...
Main sources of deviation1. COD, Nitrogen, cyanide control.2. B(a)P concentration high.3. Leakage, charging and pushing   ...
Changes NeededPlant and equipment    Operational1. Dry quenching.      1. Better cleaning.2. Taller chambers.    2. Better...
NON RECOVERY OVENSSunday, November 18,                       592012
CO oven serves the           following functions1. Provides coke for Blast Furnace.2. Recovers by products like tar   with...
However, the recovery          type coke ovens also             produces PAH              PAH emanates due to the         ...
In the non recovery coke            oven1. CO oven gas is wholly burnt   without any possibility of   recovery of by produ...
But, the flip side1. Less coke yield as coke is also   burnt.2. Air emissions tend to be high   due to high pressure as th...
Performance can be           improved through1. Stamp charging.2. Dry quenching.Sunday, November 18,                      ...
Comparative Gross Coke             Yield                                            Company wise Gross Coke Yield 2009-10 ...
BF to Gross Coke Yield Recovery Ovens                               Non recovery OvensCompany wise BF Coke Yield to Gross ...
Sources of Air Pollution in   Non recovery ovens• Stack emissions connected to  Waste Heat Recovery Boilers.• Fugitive Emi...
Other emissions• Negligible waste water discharge.• Almost no hazardous solid waste.Sunday, November 18,                  ...
Performance of non          recovery coke ovensPlant                  Grades• Bhushan Power and    • Two leaves  Steel, Od...
Major Areas of Deviances• Unable to match up in waste  heat generation.• Unable to match up to BF coke  yield.• Unable to ...
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Coke oven

  1. 1. Pollution and Pollution Control Performance and Measures in India COKE OVENS Reference: “Into The Furnace”. CSE, Delhi.2011Sunday, November 118, 2012
  2. 2. Coke Ovens is complex of distinct plants Coke Oven, By Product Plant, Effluent Treatment PlantSunday, November 218, 2012
  3. 3. Presentation of CSE Report, June 2012 on the Iron and Steel Industry in India Susmita Dasgupta JPC, ERUSunday, November 318, 2012
  4. 4. Presentation I COKE OVENSSunday, November 418, 2012
  5. 5. There is a variant to this complex in the form of Coke oven heat recovery/non recovery type.Sunday, November 518, 2012
  6. 6. India has 32 million tonnes of annual coke producing capacity Of this 23 mtpa is the by product recovery type 9 mtpa is non recovery type Of the 9 mtpa, 6 mtpa is with the merchant coke producers. The rest 3 mtpa is with integrated plants like Bhushan Steel.Sunday, November 618, 2012
  7. 7. The basic processes are• Coal is heated in Coke Oven in the absence of air to yield coke.• Volatile matters wholly and partially combusted evaporate into CO Gas which is quenched and collected.• Collected gas is then cooled and distilled to yield by products like tar, benzene, napthalene and clean of sulphur.• Water from condensation and CO cleaning is collected and passed on to Effluent Treatment Plants.• Treated water and solid waste is generated.Sunday, November 718, 2012
  8. 8. Three Basic Processes Coke Oven Gas to by products. Effluent Coal to coke. By products are Treatment of Coke goes to recovered Water pusher. through CO oven Gas condensation. Discharges goes to By Waste Water water and Product Plant goes to Effluent sludge Treatment PlantSunday, November 818, 2012
  9. 9. Pollution From Coke Ovens Coal CO Gas Coke By Water Dust productsSunday, November 18, 92012
  10. 10. 23 million tonnes of annual capacity COKE OVEN BY PRODUCT RECOVERY TYPESunday, November 1018, 2012
  11. 11. Kinds of PollutionDue to combustion of Due to incompletecoal combustion • PAH• Particulate matter compounds, carcino• S02 genic• CO• Nox • During distillation of by product. • During treatment of waste water. • May be contained both in air as well as water.Sunday, November 1118, 2012
  12. 12. Kinds of Pollution ..Fugitive Process• Unintended waste • Generated out of due to leakages. processes like• They are PAH water, particulate compounds found in matter, solid non air, water or sludge. hazardous waste.• Tar sludge, benzol • Usually non sludge. hazardous.• Usually hazardous. • Completed• Incomplete processes. processes.• They happen due to high pressure generated in the ovens and decanters.Sunday, November 1218, 2012
  13. 13. Kinds of pollution ..• Air• Water• Solid sludge.Sunday, November 1318, 2012
  14. 14. Usually air emissions. POLLUTION IN COKE OVENSSunday, November 1418, 2012
  15. 15. Sources of Pollution in Coke Ovens1. Splutter when coal is placed in the heated oven, called charging emission. This contains both particulate matter and PAH compounds.2. Due to high pressure of volatile matter inside oven during heating gas leaks out. This is diffuse emission.3. When volatile matter is wholly burnt and coke remains, dust is emitted. This is combustion emission.4. When coke is done and is pushed out of ovens into the pusher car, soot blows out. This is called pusher emission.5. When Coke Oven Gas is quenched with water, water evaporates into steam with particulate matter, So2, Nox and CO. This is called quenching emission.Sunday, November 1518, 2012
  16. 16. Charging emissions can be prevented by• Increasing compactness in coal packing. Change from top charging to stamp charging.• Increase the volume of coke ovens to reduce frequency of charging.• Increasing height of chamber.Sunday, November 1618, 2012
  17. 17. Diffuse emission can be prevented by• Using self sealing doors.• Use of magnetic lid.• Use of screw tightened pipes.• Water sealing of ascension pipes.• Plugging charging holes.• Containing build up of pressure in the oven through variable pressure controller.• Increasing compactness of feed through stamp charging.Sunday, November 18, 172012
  18. 18. Combustion emission due to under firing of stack can be contained through• Arrest of dust containing PM, So2, Nox, CO and CO2.• Having larger oven sizes through increase in chamber height.• Stamp charging.• HPLASunday, November 1818, 2012
  19. 19. When coke is done, and is pushed out of the oven into container cars on rails, soot can be controlled by• Having a land based stationary emission control device instead of the suction hood and bag filter attached to the mobile car.Sunday, November 1918, 2012
  20. 20. Quenching emissions• When water is sprayed on CO Gas to cool the fluid, water evaporates producing steam. The steam contains particulate matter, CO, So2 and Nox.• Dry quenching with ammonia helps in reducing this type of emissions.Sunday, November 2018, 2012
  21. 21. Emissions are of two kindsFugitive Process• Fugitive emissions • Usually wholly happen due to gas leaks. combusted matter• This may contain both in the form of combusted and dust, namely incompletely PM, Nox, So2 and combusted matter. Incomplete CO. combustion has • Pollution control traces of PAH levels measured by the rules pertain to concentration of emission norms and benzene pyrelene in the emission. • Pollution control• Pollution control rules devices. pertain to equipment design.Sunday, November 2118, 2012
  22. 22. The emissions from CO Plant is air emission• We track particulate matter, So2, CO and Nox.• We track the concentration of B(a)p, a PAH compound that contains poisonous cyanide and emanates out of improperly combusted volatile matter in coal.Sunday, November 2218, 2012
  23. 23. Ministry of Environment andForests have specifications for• Emission norms and standards.• Plant design equipment.• Specification of pollution control equipments.Sunday, November 2318, 2012
  24. 24. Comparison of Air Emission Standards For Coke Oven Recovery Fugitive Visible Emissions Units India Europe USA Percentage Leaked From Doors % 55 to 10 4 Percentage Leaked from lids % 1 1 0.4 Percentage laked from ascension pipes % 4 1 2.5 Charging Emissions seconds/ charge 16 20 14 Benzo(a)pyrene in the work area Units India Europe USA Battery area Top ug/m3 5 5 Other units in coke plant ug/m3 2 2 Ambient air standards ng/m3 10 6 Underfiring Stack Emissions Units India Europe USA Particulate Matter mg/Nm3 50 20 50 Sulphur dioxide mg/Nm3 800 200 to 500 500 Nitrogen Oxide mg/Nm3 500350 to 500 750 kg/tonne of Carbon Monoxide gross coke 3 3 3 Other Stack Related Emissions Units India Europe USA Stamp Charging PM mg/NM3 25 gm/tonne of coke Coke Pushing Emissions pushed 5 5 Sulphur in Coke Gas Recycled mg/Nm3 800 300 Wet Quenching Units India Europe USA gm/tonne of coke 20 (dry) Particulate Matter from Tower produced 50 (wet) 25 (wet) mg/Nm3 Source: CSE, June 2012Sunday, November 18, 242012
  25. 25. Norms Provided by the GSR 46(E) Notification dated 3.2.2006 New Baterries for Rebuilt Existing Fugitive Visible Emissions Units Greenfield sites Batteries Batteries Percentage Leaked From Doors % 5 10 10 Percentage Leaked from lids % 1 1 1 Percentage laked from ascension pipes % 4 4 4 seconds/ Charging Emissions charge 16 (HPLA) 50 (HPLA) 75 Benzo(a)pyrene in the work area Units Green Field Rebuilt Existing Battery area Top ug/m3 5 5 5 Other units in coke plant ug/m3 2 2 2 Ambient air standards ng/m3 10 10 10 Underfiring Stack Emissions Units Particulate Matter mg/Nm3 50 50 50 Sulphur dioxide mg/Nm3 800 800 800 Nitrogen Oxide mg/Nm3 500 500 500 kg/tonne of Carbon Monoxide gross coke 3 3 3 Other Stack Related Emissions Units Green Field Rebuilt Existing Stamp Charging PM mg/NM3 25 25 25 gm/tonne Coke Pushing Emissions (land based of coke system applicable) pushed 5 5 not not Sulphur in Coke Gas Recycled mg/Nm3 800 specified specified Wet Quenching Units Green Field Rebuilt Existing gm/tonne of coke not Particulate Matter from Tower produced 50 50 specifiedSunday, November 2518, 2012
  26. 26. (a) air-cooled self-sealing doors; (b) the hydro-jet cleaning system shall be provided for the door and door frame cleaning with a facility of hydro jet pressure of 2 600 kg/cm ; (c) the charging should be accomplished with hermetically sealed charging sleeves and screw feeder in charging car. The charging car should also be equipped with magnetic lid lifter and lid and frame cleaning mechanism (applicable to top charging batteries); (d) to provide aspiration through high-pressure ammonia liquor (HPLA) injection in goose neck and emission should be transferred directly to gas collecting mains; (e) water sealed AP covers should be provided; (f) computerized combustion control and moisture control systems.Sunday, November 2618, 2012
  27. 27. Among the pollution control equipment it specifies• Land based stationary precipitator.• Norms for the use of effluent treated water for wet quenching.Sunday, November 18, 272012
  28. 28. Poor environment management also means poor economic efficiency COKE OVEN PERFORMANCE PARAMETERSSunday, November 18, 282012
  29. 29. Fugitive Emission Standards Compliance Status 2009-10 Complianc Name of Steel Plant Battery No e Vizag Steel Plant Battery 1 Yes Visakhapatnam Battery 2 Yes 50% Battery 3 No Battery 4 No SAIL, Rourkela Battery 1 Yes 40% Battery 2 No Battery 3 No Battery 4 Yes Battery 5 No Tata Steel Battery 3 No Jamshedpur Baterry 5 No 33% Baterry 6 No Baterry 7 No Baterry 8 Yes Baterry 9 Yes JSW Steel, Vijayanagar Battery 3A Yes 100% Battery 3B Yes Battery 3C Yes Battery 3D Yes Neelachal Ispat, Orissa Battery 1 Yes 100% Source: CSE 2012Sunday, November 2918, 2012
  30. 30. Coke Oven Stack PM EmissionsCoke Oven StackParticulate Matter 2008-09 and 2009-10Emission Plant mg/Nm3 Vizag Steel, 4 43.2 SAIL RSP,2 46Improve quality of coal. Tata Steel, 3 83Stamp charging increases JSW Steel 10bulk density. Neelachal Ispat 56Variable pressure controller. SAIL BSP, 1 77.7 SAIL BSP, 2 75.4 SAIL BSP, 3 66.6 SAIL, BSP 7 80.3 SAIL, BSP 8 83.3 SAIL, BSP 9 89.3 SAIL, BSP 10 94.4 SAIL, DSP, 3 132.3 SAIL, IISCO, 8 113.68 SAIL, IISCO, 9 61.45 Source; CSE, June 2012Sunday, November 18, 302012
  31. 31. Coke Oven Gas Coke Oven Stack PM EmissionsEmissions 2008-09 and 2009-10High emissions indicateleakages. Plant mg/Nm3Can be corrected with self Vizag Steel, 4 43.2sealing doors. SAIL RSP,2 46Stamp Charging. To improvebulk density of charge. Tata Steel, 3 83Increase in coke ovenchamber height. JSW Steel 10Increase in coke oven Neelachal Ispat 56volume. SAIL BSP, 1 77.7Water sealed ascension SAIL BSP, 2 75.4pipes. SAIL BSP, 3 66.6 SAIL, BSP 7 80.3Hydrojet cleaning. SAIL, BSP 8 83.3 SAIL, BSP 9 89.3Magnetic lid SAIL, BSP 10 94.4 SAIL, DSP, 3 132.3Dry Quenching SAIL, IISCO, 8 113.68 SAIL, IISCO, 9 61.45Sunday, November Source; CSE, June 2012 3118, 2012
  32. 32. BF to Gross CokeYield Company wise BF Coke Yield to Gross Coke Plant Yield % Vizag Steel 83.2 SAIL RSP 88.8 Tata Steel 80This parameter indicates the JSW Steel 91.9control of the company toraw material resources Neelachal Ispat 87.8especially coal. SAIL, BSP 82.5 SAIL, BSL 83 SAIL, DSP 79 SAIL, IISCO 89 Indias Average 84 Global Best 92 Source: CSE, June 2012Sunday, November 18, 322012
  33. 33. Gross Coke YieldImproves Company wise Gross Coke Yield 2009-10 Plant Gross Coke Yield % Vizag Steel Plant 74.4If quality of coal is better. SAIL, RSP 74.6 Tata Steel 75.6Bulk density improvesthrough stamp charging. JSW 72 Neelachal Ispat 75.6Coke chamber heightincreases. SAIL, BSP 74 SAIL, IISCO 76Variable pressure monitor isinstalled. Indias Average 74.5 Global Best 81 Source: CSE, June 2012Sunday, November 18, 332012
  34. 34. Coke Oven GasCollection Rate Company wise Coke Oven Gas Collection Rate 2009-10Would improve if Plant Nm3/tonne of dry coke Vizag Steel 340Wet quenching is replacedby dry ammonia quenching. SAIL RSP 318 Tata Steel 310HPLA rather than GasBurning Chamber is JSW Steel 320installed. Neelachal Ispat 332Water sealed ascension SAIL, BSP 317pipes are used. SAIL,BSL 310Coke yield in the oven SAIL, DSP 290improves. SAIL, IISCO 299Low levels of particulate Indias Average 316matter is emitted. Global Best Practice 388Coal has low sulphurcontent. Source: CSE, June 2012Sunday, November 18, 342012
  35. 35. Specific Thermal Energy ConsumptionSpecific Thermal 2009-10Efficiency Coke Oven kcal/kg gross coke Vizag Steel Plant 813 SAIL, RSP 786Dry quenching Tata Steel 794helps in heatrecovery. JSW Steel Total 885 JSW 3A and 3D 900Proper sealing ofdoors, lids, pipes Neelachal Ispat 764improve thermal SAIL Bhilai Total 662efficiency. SAIL Bhilai 5 546Stamp charging SAIL, IISCO 781improves thermalefficiency. Indias Average 764 Global Best 496 Source: CSE, June 2012Sunday, November 18, 352012
  36. 36. List of Clean Technologies1. Increase in coke oven chamber height.2. Move over from top to stamp charging to increase density in bulk.3. Self sealed doors.4. Magnetic lids.5. Hydrojet cleaners.6. Water sealed ascension pipes.7. HPLA8. Land based ESPSunday, November 18, 362012
  37. 37. Technology #1 Increase in Chamber Height• This increases the volume of the oven and reduces the need to repeatedly open the doors. Reduces leakage/diffuse emissions.• The number of bushings is reduced. Decreases pushing emission.• Global best practice = height of 8.3 metres.• India’s average 4.3meters.• Volume of coke oven increases. 8.3 m height = 70 tonne of oven volume.Sunday, November 18, 372012
  38. 38. Technology # 2 Stamp Charging• Top charging accommodates 765 kgs/m3 volume. Stamp charging accommodates 1150kg.m3 volume.• More coal can be pushed at a time and this reduces charging and pushing emissions.• Stamp charging improves coke strength and this helps BF productivity.• Combustion emissions/stack emissions are reduced due to increased coke strength.Sunday, November 18, 382012
  39. 39. Technology #3 Self sealed Doors• Gas pressure is kept at a minimum inside the oven so that tar sealing gaskets are formed along the doors.• Spring loaded stainless steel doors.• GSR 46(E) notification of 3.2.2006 specifies self sealing doors.• Of the 45 ovens studied, only 18 have self sealing doors.• This is 40% compliance.Sunday, November 18, 392012
  40. 40. Technology #4 Magnetic Lid• In order to minimise leakage/diffuse emissions, magnetic lids are prescribed.• GSR 46(E) dated 3.2.2006 specifies magnetic lids.Sunday, November 18, 402012
  41. 41. Technology #5 Hydrojet Cleaners Technology # 6Water sealed ascension pipes• Hydrojet cleaners helps clean gas exit zones to help declog.• GSR 46(E) 3.2.206 has specified the use of such cleaners.• Since gas tends to leak through ascension pipes due to high pressure built up in the oven, water sealed ascension pipes are recommended.Sunday, November 4118, 2012
  42. 42. Technology #7 High Pressure Liquid Ammonia Aspirator• This helps capture emission by reducing the pressure of gas through ammonia cooling.• Used in dry quenching technology for gas collection.• Used in stamp charging to reduce charging emissions.• Very useful for capturing PAH emissions emanating out of incomplete combustion.• GSR 46(E) 3.2.2006 notification exists.Sunday, November 18, 422012
  43. 43. Technology #8 Land Based Stationary Air Filter• Coke is pushed out in container cars on rails equipped with suction hood and bag filters.• GSR 46(E) 3.2.2006 recommends the use of land based stationary precipitator for control of dust during coke pushing.Sunday, November 18, 432012
  44. 44. Design of Coke Ovens In India Gross Coke Coal Holding Capacity in Number of Chamber Capacity (dry million tonnes ovens/ Height in Type of coal) inName of Plant Battery per annum batteries metres Charging tonnes/ ovenVizag Steel Battery 1 0.8 67 7 top 31.6 Battery 2 0.8 67 7 top 31.6 Battery 3 0.8 67 7 top 31.6 Battery 4 0.8 67 7 top 31.6SAIL, RSP Battery 1 0.48 70 4.5 top 17 Battery 2 0.48 70 4.5 top 17 Battery 3 0.48 70 4.5 top 17 Battery 4 0.56 80 4.5 top 17 Battery 5 0.56 80 4.5 top 17Tata Steel Battery 3 0.3 54 4.5 top 17 Battery 5 0.5 30 4.5 Stamp 24.3 Battery 6 0.48 60 4.5 Stamp 24.3 Battery 7 0.48 54 4.5 Stamp 24.3 Battery 8 0.5 70 4.5 Stamp 24.3 Sunday, November 18, Battery 9 0.5 70 4.5 Stamp 24.3 44 2012JSW Vijaynagar Battery 3A 0.38 56 4.3 Stamp 27
  45. 45. Technologies Adopted in Indian Coke OvensSunday, November 18, 452012
  46. 46. Sulphur is removed, by products are retrieved BY PRODUCT PLANTSunday, November 18, 462012
  47. 47. New technologies for sulphur removal• Sulphur content in CO Gas prior to treatment is 1800-4000 mg/Nm3.• In ammonia scrubbing, sulphur content comes down to 800 mg/Nm3.• In wet oxidative system, sulphur content comes down to 200 mg/Nm3Sunday, November 18, 472012
  48. 48. Sources of Pollution in By Product Plant• Water is generated when the CO gas condenses.• Water may contain PAH.• Water may also contain sulphur.• Sulphur sludge.• Tar sludge• Benzol sludge.Sunday, November 18, 482012
  49. 49. Here waste water enters for treatment and cleaning. Also sludge from distilled by products are cleaned into non hazardous solid waste. EFFLUENT TREATMENT PLANTSunday, November 18, 492012
  50. 50. Steps in Effluent Treatment Plant1. Tar is removed.2. Suspended solids captured.3. BOD,COD removed.4. Sludge is thickened. Water released.5. Ammonia is removed.6. Cyanide is removed.7. Clean water flushed.8. Solid waste disposed.Sunday, November 18, 502012
  51. 51. Water Treatment Parameters in ETP Waste Water Treatment Plant ParametersParameter Units Tata Steel SAIL, RSP JSW, VijaynagarpH 7.8 8.5 to 9.5 8.2 to 8.7Ammonia Nitrogen mg/litre 150 300 to 350 120-348Phenol mg/litre 330 400 to 450 264 to 725Cyanide mg/litre 4.8 to 5.6 20 7.4 to 262Oil and grease mg/litre 5 to 10 30 to 40 7.7 to 24.6BOD mg/litre 1150COD mg/litre 2400 1939 to 2931Total SuspendedSolids mg/litre 50 138 to 569Mixed LiquorSuspended Solids 4000 3248Source: CSE, June2012 Sunday, November 18, 51 2012
  52. 52. Water Consumption in Coke Oven• Coke Ovens consume 13% of all water required in the steel plants.• Water is used for cooling ovens, quenching off gas.• Cleaning plant and machinery.• Water is condensed out of coal, out of the Coke Oven Gas while recovering tar and other products.• Also during cyanide dilution.Sunday, November 18, 522012
  53. 53. Dry Quenching reduces water consumption. Waste Water in ETP 2009-10 Plant m3/tonne gross coke Coke Oven Plants 2009-10 Vizag Steel Plant 0.2 Tata Steel 0.27 m3/tonne Method ofPlant gross coke Quenching SAIL, RSP 0.44JSW 0.55 dry JSW 0.5SAIL, RSP 0.72 wet Global Best 0.3Tata Steel 2.3 wet Source: CSE June 2012Source: CSE, June 2012 Sunday, November 18, 53 2012
  54. 54. Solid waste can beNon hazardous Hazardous1. Coal dust as 1. Tar decanter spillage from sludge from by carts, storage product plant. and handling 2. Coke activate areas. sludge from2. Undersize ETP. particles of 3. Benzol muck. coke. 4. Sulphur muck.3. Spillage during 5. Waste oil and coke pushing. grease with4. All are collected cyanide. and recycled.Sunday, November 18, 542012
  55. 55. Hazardous Solid Waste Generation and Disposal c Hazardous Solid Waste Disposal in 2009-10 Vizag Steel Plant SAIL RSP Tata Steel JSW Steel quantity quantity quantity quantityHazardous generated Method of generated Method of generated Method of generated Method ofSolid Waste in tonnes disposal in tonnes disposal in tonnes disposal in tonnes disposalTarDecanterSludge 2956 100% recycled 60 100% recycled 3180 100% recycled 300 100% recycledOther tarwastes 77.7 100% recycled 96 waste pitBenzolmuck 468.17 100% recycledCoke OvenETPactivatedsludge/tarry waste 751.37 100% recycled 8 100% recycled 47.5 100% recycled 365 100% recycled sold toSulphur authorisedwaste none 10 agencies sold to authorised 300 waste pit 330 agenciesSource: CSE, June 2012 Sunday, November 18, 55 2012
  56. 56. Overall Performance of CokeOvens, By Product Recovery• Vizag Steel 3 leaves• Tata Steel 2 leaves• JSW 2 leaves• Neelachal Ispat 2 leaves• SAIL, RSP 1 leaf• SAIL others: non performers.Sunday, November 18, 562012
  57. 57. Main sources of deviation1. COD, Nitrogen, cyanide control.2. B(a)P concentration high.3. Leakage, charging and pushing emissions.4. Stack PM emissions.5. Hazardous waste disposal.6. CO gas collection rate.7. Dry quenching technology.8. Coke oven chamber size.Sunday, November 18, 572012
  58. 58. Changes NeededPlant and equipment Operational1. Dry quenching. 1. Better cleaning.2. Taller chambers. 2. Better draining.3. Self sealing 3. Keener COD, doors, magnetic BOD practices. lids, water 4. Improved tar sealing. decanting.4. HPLA system. 5. Improved solid5. Variable pressure hazardous waste monitor. disposal.6. Land based stationary precipitator.Sunday, November 18, 582012
  59. 59. NON RECOVERY OVENSSunday, November 18, 592012
  60. 60. CO oven serves the following functions1. Provides coke for Blast Furnace.2. Recovers by products like tar with economic value.3. Recovers Coke Oven Gas which is a source of heating for the steel plant.Sunday, November 18, 602012
  61. 61. However, the recovery type coke ovens also produces PAH PAH emanates due to the attempt to recover by products. PAH is carcinogenic and the US has banned the recovery oven for future ovens.Sunday, November 18, 612012
  62. 62. In the non recovery coke oven1. CO oven gas is wholly burnt without any possibility of recovery of by products.2. Instead, more heat is recovered from the process.3. No waste water discharge. No need for elaborate ETP.4. PAH is negligible.5. More coal holding capacity.Sunday, November 18, 622012
  63. 63. But, the flip side1. Less coke yield as coke is also burnt.2. Air emissions tend to be high due to high pressure as the volatile matters are burnt inside the coke chamber.3. Takes up more space.Sunday, November 18, 632012
  64. 64. Performance can be improved through1. Stamp charging.2. Dry quenching.Sunday, November 18, 642012
  65. 65. Comparative Gross Coke Yield Company wise Gross Coke Yield 2009-10 Company wise Gross Coke Yield 2009-10 Non recovery Oven Gross Coke Yield % Recovery Coke Oven Plant Gross Coke Yield % Visa Steel 68.3 Vizag Steel Plant 74.4 JSPL 68.3 SAIL, RSP 74.6 Bhushan Steel 72.9 Tata Steel 75.6 JSW 71 JSW 72 Indias Average 70.2 Neelachal Ispat 75.6 Global Best 76 SAIL, BSP 74 Source: CSE, June SAIL, IISCO 76 2012 Indias Average 74.5 Global Best 81Source: CSE, June 2012 Sunday, November 18, 65 2012
  66. 66. BF to Gross Coke Yield Recovery Ovens Non recovery OvensCompany wise BF Coke Yield to Gross Coke Company wise BF Coke Yield to Gross Coke Plant Yield % Non recovery Yield %Vizag Steel 83.2 Visa Steel 87SAIL RSP 88.8 JSPL 90Tata Steel 80 Bhushan Steel 90JSW Steel 91.9 JSW 87.6Neelachal Ispat 87.8 Indias Average 88.6SAIL, BSP 82.5 Global Best 92SAIL, BSL 83SAIL, DSP 79 Source: CSE, June 2012SAIL, IISCO 89Indias Average 84Global Best 92Source: CSE, June Sunday, November 18,2012 66 2012
  67. 67. Sources of Air Pollution in Non recovery ovens• Stack emissions connected to Waste Heat Recovery Boilers.• Fugitive Emissions due to charging and pushing.• During wet quenching of coke.• All CPCB norms of air pollution limits are the same.• No suggestions on plant and equipment.Sunday, November 18, 672012
  68. 68. Other emissions• Negligible waste water discharge.• Almost no hazardous solid waste.Sunday, November 18, 682012
  69. 69. Performance of non recovery coke ovensPlant Grades• Bhushan Power and • Two leaves Steel, Odisha• Visa Steel, Kalinganagar, • Two leaves Odisha• JSPL, Raigarh • One leaf• JSW Vijaynagar • One leafSunday, November 18, 692012
  70. 70. Major Areas of Deviances• Unable to match up in waste heat generation.• Unable to match up to BF coke yield.• Unable to instal dry quenching.• Stack emissions poor.Sunday, November 18, 702012

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