02 COAL.pptx important work hard life good

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1. Topics: Classification Properties Combustion Carbonization Liquefaction and gasification Electricity generation from coal 2. COAL

2. Coal is a stored fossil fuel, occurring in the earth’s crust, which has been formed by the partial decay of plant materials accumulated millions of years ago and further altered by the action of heat and pressure. Coal is a combustible black or brownish-black sedimentary rock normally occurring in rock strata in layers called coal beds or coal seams . Coal is composed primarily of carbon along with variable quantities of other elements, chiefly hydrogen, with smaller quantities of sulfur, oxygen and nitrogen. COAL: ?

3. COAL FORMATION Over time, the chemical and physical properties of the plant remains were changed by geological action to create a solid material.

4. THEORIES OF COAL FORMATION IN SITU THEORY DRIFT THEORY - Flood /Tsunami type wave ( velocity 800 km/h) 320 million of years (earth is 4.6 billion years old) 15-20 m of plant material = 1 m of coal seam In INDIA 30 m seam of coal has been found 450-600 m of plant material might have accumulated at that place. ( Burj Khalifa in Dubai, 828 m: tallest man made structure in world)

5. THEORIES OF COAL FORMATION IN SITU THEORY 1. Brackish or fresh water , swamp land 2. Extensive accumulations of vegetable matter subjected to widespread submersion by sedimentary deposits.

6. THEORIES OF COAL FORMATION DRIFT THEORY - Flood /Tsunami type wave ( velocity 800 km/h ) Coal is formed largely from terrestrial plant material growing on dry land and not in swamps or bogs. The original plant debris was transported by water and deposited under water in lakes or in the sea. There will not be a true soil found below the seam of coal. The transported plant debris settled down in regular succession. These deposits were covered subsequently by mineral matters, sand, etc. and resulted in coal seams. The depositions might have stopped for a particular period and again began to happen depending upon the tidal and current conditions. The coal properties vary widely due to the varied types of vegetation deposited .

7. The geochemical process that transforms plant material into coal is called coalification and is often expressed as: peat → lignite → subbituminous coal → bituminous coal → anthracite COALIFICATION

8. 2. COAL

9. COALIFICATION Coal % C C H O Typical Heating value (MJ/kg) Cellulose 45 45 6 49 10 Wood (Dry) 50 50 6 44 10-11 Peat 60 60 6 34 10-12 Lignite 62 62 5 33 16-24 Bituminous coal 79 79 4 17 26-30 Anthracite 91 91 3 6 32-34 Graphite 100 100 34 Time

10. Peat Lignite Bituminous coal Anthracite Graphite COAL RANKS

11. Starting point of coal formation Does not come in the category of coal Carbon: 60-64%; Oxygen: 35-30% PEAT

12. Also known as brown coal Mark the transition of peat to coal Carbon: 60-75%; Oxygen: 30-20% Colour : black, brown, earthy Disintegrates very easily Briquetting is done LIGNITE Neyveli Lignite Corporation, Chennai Tamilnadu possesses largest reserves of l ignite in India Electricity generation: 2740 MW (4 plants)

13. BITUMINOUS COALS A. Sub-bituminous : Between lignites and bituminous Carbon : 75-83 %; Oxygen: 20-10% No caking power (Briquettes can not be made ) Also known as Steam Coal B. Bituminous : Black and banded Metallurgical coke formation Carbon : 75-90 %; Oxygen : 10-5 % C. Semi-bituminous: Steam locomotives Between bituminous and anthracite Carbon : 90-93%; Oxygen : 4-1 %

14. Highest rank of coal A harder, glossy and black coal Extreme of metamorphosis from the original plant material Carbon: 93+%; Oxygen: 2-1% Caking power zero ANTHRACITE

15. Technically the highest rank Difficult to ignite Not used as fuel Mostly used in pencils and as a lubricant in powder form GRAPHITE

16. UNUSUAL COALS A. Cannels: Found rarely High hydrogen content Burn with smoke and bright flame Does not fall in any category B. Torbanites : Also known as Boghead coal Named after Torbane Hill of Scotland Rich in paraffin oil Fine grained coal

17. Coal Resource is the amount of coal that may be present in a deposit or coalfield. This does not take into account the feasibility of mining the coal economically. Not all resources are recoverable using current technology. Coal Reserves can be defined in terms of proved (or measured) reserves, probable (or indicated) reserves and guessed (or inferred) reserve. Proved Coal Reserve is that part of the total coal resource for which quantity and quality can be estimated with a high level of confidence. Indicated Coal Reserve is that part of the total coal resource for which quantity and quality can be estimated with reasonable levels of confidence based on information gathered and supported by Interpretive Data. Inferred Coal Reserve is that part of the total coal resource estimate for which quantity and quality can only be estimated with low levels of confidence. COAL RESOURCES AND RESERVES - INDIA

18. COAL RESERVES IN INDIA, Mt Formation Proved Indicated Inferred Total Gondwana Coals 125315 142407 32350 300072 Tertiary Coals 594 99 799 1493 Total 125909 142506 33149 301564 Gondwana coals: 250-325 million years Tertiary coals: 10-60 million years, high S content 2-8% Gondwana coals: Name was given by H.B . Medlicott . He was with Thomson College from August 15, 1854 onward , Museum Earth Sciences Department, IIT Roorkee

19. Name of the state Reserves in billion tonne % of total reserves JHARKHAND 80.71 26.76 ODISHA 75.07 24.89 CHATTISHGARH 52.53 17.42 WEST BENGAL 31.31 10.38 MADHYA PRADESH 25.67 8.51 ANDHRA PRADESH 22.48 7.45 MAHARASTRA 10.98 3.64 OTHERS 2.81 0.95 COAL RESERVES IN INDIA A total of 301.56 billion tonnes of coal reserves are estimated by GSI Prime coking coal: 5.313 billion tonnes M edium and semi-coking coals: 28.76 billion tonnes Non-coking coals: 266.00 billion tonnes Tertiariary coal: 1.49 billion tonnes

20. STATEWISE COAL RESOURCES State Geological Resources of Coal (in MT) Proved Indicated Inferred Total Jharkhand 39480 30894 6338 76712 Orissa 19944 31484 13799 65227 Chhattisgarh 10910 29192 4381 44483 West Bengal 11653 11603 5071 28327 Madhya Pradesh 8041 10295 2645 20981 Andhra Pradesh 9194 6748 2985 18927 Maharashtra 5255 2907 1992 10154 Uttar Pradesh 866 196 1062 Meghalaya 89 17 471 577 Assam 348 36 3 387 Bihar 160 160 Sikkim 58 43 101 Arunachal Pradesh 31 40 19 90 Nagaland 9 13 22 Total 105820 123470 37920 267210

21. LIGNITE RESERVES IN INDIA, B T State Quantity Tamil Nadu 36.490 Rajasthan 6.349 Gujarat 2.722 Puducherry 0.417 Jammu and Kashmir 0.028 Kerala 0.01 West Bengal 0.004 India 46.02

22. TYPE OF COAL RESERVE (in MT) PROVED INDICATED INFERRED TOTAL (A) Coking 17545 13766 2102 33413 Prime Coking 4614 699 5313 Medium Coking 12449 12064 1880 26393 Semi-Coking/weakly 482 1003 222 1707 (B) Non-Coking 87798 109614 35312 232724 (C) Tertiary Coal 477 90 506 1073 Grand Total 105820 123470 37920 267210   Cokes are the solid carbonaceous material derived from destructive distillation of low-ash , low-sulfur bituminous coals. COAL RESERVES OF INDIA Charcoal: Wood

23. PRODUCTION OF COAL IN INDIA, MT Singareni Collieries Company Ltd.(SSCL)

24. IMPORT OF COAL, MT Coal type 2015-16 2016-17 2017-18 2018-19 2019-20 2020-21(Prov.) 2021-22(Prov.)* Coking Coal 44.56 41.64 47.00 51.84 51.83 51.20 28.02 Non-Coking Coal 159.39 149.36 161.25 183.51 196.70 164.05 81.34 Total Coal Import 203.95 191.01 208.25 235.35 248.53 215.25 109.36 Coke 3.07 4.35 4.58 4.93 2.87 2.46 1.31

25. GRADING OF INDIAN COAL For coking coal Gradation is based on ash content Non-coking coal Gradation is based on Useful Heating Value (UHV) For semi coking/weakly coking coal Gradation is based on ash plus moisture content .

26. GRADING OF COKING COAL GRADE ASH CONTENT Steel Grade-I Not exceeding 15% Steel Grade-II Exceeding 15% but not exceeding 18% Washery Grade-I Exceeding 18% but not exceeding 21% Washery Grade-II Exceeding 21% but not exceeding 24% Washery Grade-III Exceeding 24% but not exceeding 28% Washery Grade-IV Exceeding 28% but not exceeding 35% Steel Grade Coal is used in Steel Industries. Washery Grade Coal is used as fuel in thermal power plants.

27. GRADING OF NON-COKING COAL Grade Ash % + Moisture % (at 60 % RH & 40 o C) Useful Heat Value (UHV) (in kcal/kg ) UHV= 8900-138(Ash% + Moisture % ) A Not exceeding 19.5 Exceeding 6200 B 19.6 to 23.8 Exceeding 5600 but not exceeding 6200 C 23.9 to 28.6 Exceeding 4940 but not exceeding 5600 D 28.7 to 34.0 Exceeding 4200 but not exceeding 4940 E 34.1 to 40.0 Exceeding 3360 but not exceeding 4200 F 40.1 to 47.0 Exceeding 2400 but not exceeding 3360 G 47.1 to 55.0 Exceeding 1300 but not exceeding 2400

28. GRADING OF SEMI-COKING AND WEAKLY-COKING COAL GRADE ASH+MOISTURE CONTENT Semi coking grade-I Not exceeding 19% Semi coking grade-II Exceeding 19% but not exceeding 24%

29. ROYALITY TO STATES Nationalization in 1972 Act 1976: Coal India Ltd. (CIL) & Singareni Collieries Company Ltd.(SSCL) Coal companies are paying the royalty to states This varies from 14% on coal and 6% on lignite (other than West Bengal) w.e.f . May 10, 2012 Rs 2.5 to 7.50 per tonne depending upon the quality of coal in West Bengal w.e.f . May 10, 2012

30. ROYALITY TO STATES Royalty Paid by Coal Companies to the States ( In Crores Rupees )   2019-20 2020-21 2021-22 Chhattisgarh 2350.21 2292.88 2386.29 Jharkhand 3211.03 2879.95 3623.49 Odisha 2139.45 1519.31 2700.21 Madhya Pradesh 2069.38 3199.42 2709.77 Maharashtra 1198.8 1153.85 1753.34 Telangana 1537.36 1429.74 250 West Bengal 18.96 12.64 15.96 Assam 31.34 5.89 Uttar Pradesh 406.39 638.23 475.25 Total 12962.92 13131.91 13914.31

31. ANALYSIS OF COAL Proximate analysis Ultimate analysis Heating/calorific value

32. ANALYSIS Moisture content: 105 - 110 o C Volatiles : 925 ± 15 o C for 7 min time (with lid ) (with out moisture) Ash : 800 ± 15 o C (without lid ) Fixed carbon by difference PROXIMATE ANALYSIS Proximate analysis shall comply IS:1350-I (1984) REPORTING As received basis - M,VM, A, FC (in %) Moisture free /Dry basis -VM, A, FC (in %) Dry ash free basis - VM, FC ( in %)

33. A sample of finely ground coal of mass 0.9945 g was placed in a crucible of 8.5506 g in an oven, maintained at 105 o C for 4.0 ks . The sample was then removed, cooled in a desiccator and reweighed; the procedure being repeated until a constant total mass of 9.5340 g was attained. A second sample of mass 1.0120 g in a crucible of mass 8.5685 g was heated with a lid in a furnace at 920 o C for 420 s . On cooling and reweighing, the total mass was 9.1921 g. This sample was then heated without lid in the same furnace maintained at 815 o C until a constant total mass of 8.6255 g was attained. Carry out the proximate analysis of the sample and express the results on “as received” and “dry, ash-free” basis. EXAMPLE OF PROXIMATE ANALYSIS

34. A sample of finely ground coal of mass 0.9945 g was placed in a crucible of 8.5506 g in an oven, maintained at 105 o C for 4.0 ks . The sample was then removed, cooled in a desiccator and reweighed; the procedure being repeated until a constant total mass of 9.5340 g was attained. Determination of Moisture from first sample: Mass of sample = 0.9945 g Mass of dry coal = (9.5340 - 8.5506) = 0.9834 g Mass of moisture = (0.9945 - 0.9834) = 0.0111 g % Moisture = 0.0111×100/0.9945 = 1.11% EXAMPLE OF PROXIMATE ANALYSIS ( contd …)

35. A second sample of mass 1.0120 g in a crucible of mass 8.5685 g was heated with a lid in a furnace at 920 o C for 420 s . On cooling and reweighing, the total mass was 9.1921 g. This sample was then heated without lid in the same furnace maintained at 815 o C until a constant total mass of 8.6255 g was attained. Heating up to 920ºC in absence of air removes volatile matters, subsequent heating up to 725ºC in presence of air burns all fixed carbon of the sample leaving behind ash in the crucible. Determination of Ash from second sample: Mass of sample = 1.0120 g Mass of crucible = 8.5685 g Mass of ash (remnant in crucible) = (8.6255 - 8.5685) = 0.0570 g % Ash = 0.0570 × 100/1.0120 = 5.63 % EXAMPLE OF PROXIMATE ANALYSIS ( contd …)

36. A second sample of mass 1.0120 g in a crucible of mass 8.5685 g was heated with a lid in a furnace at 920 o C for 420 s . On cooling and reweighing, the total mass was 9.1921 g. This sample was then heated without lid in the same furnace maintained at 815 o C until a constant total mass of 8.6255 g was attained. Determination of Volatile matters from second sample: Initial mass of sample + crucible = 1.0120 + 8.5685 = 9.5805 g Final mass after heating up to 920ºC (without air) = 9.1921 g Mass of volatile matter + moisture = Initial – Final mass = (9.5805-9.1921) g = 0.3884 g % Moisture + Volatiles matters = 0.3884 x 100/1.0120 = 38.3794 % % Volatile matters = 38.3794 – 1.11 (% Moisture) = 37.26 % EXAMPLE OF PROXIMATE ANALYSIS ( contd …)

37. % Moisture (M) = 1.11% % Ash (A) = 5.63 % % Volatile matters (VM) = 37.26 % % Fixed carbon (FC) = 100 – (%M + %A + %VM) = 100 – (1.11+ 5.63+ 37.26) = 56.0 % EXAMPLE OF PROXIMATE ANALYSIS ( contd …)

38. Proximate analysis as received basis Moisture : 1.11 % Ash : 5.63 % Volatile matter : 37.26 % Fixed carbon : 56.00 % Proximate analysis on dry, ash free basis Moisture + Ash : 1.11 + 5.63 = 6.74% Fixed carbon : 56.0 x 100 /(100-6.74) = 60.04 % or : 56.0/(37.26+56.00)*100=60.04% Volatile matter : 37.26 x 100 /(100-6.74) = 39.95 % or : 37.26/(37.26+56.00)*100=39.95% REPORTING OF PROXIMATE ANALYSIS

39. Carbon Hydrogen Oxygen (by difference) Sulfur : 0.5-8.50 % Nitrogen : 1.0-2.25 % Phosphorus : 0.1%; Blast Furnace: < 0.01 % Chlorine ULTIMATE ANALYSIS Ultimate analysis shall comply IS:1350- IV (1974 ) Or CHNS analysis Substance Content Mercury 0.10 ppm Arsenic 1.4 – 71 ppm Selenium 3 ppm Other than moisture and ash

40. Calculated from proximate analysis Calculated from ultimate analysis Experimental determination HEATING VALUE OF COAL Gross/High heating value (water vapor getting condensed after combustion) Useful/low heating value (determined by subtracting the heat of vaporization of the water from the higher heating value) Hydrogen Water (vapor or liquid phase ) Carbon Carbon dioxide (gas phase ) Latent heat of vaporization of water: 2.26 MJ/kg Amount of heat released by the combustion of unit mass of coal under standard conditions.

41. HEATING VALUE FROM PROXIMATE ANALYSIS TAYLOR AND PATTERSON RELATIONSHIP HV = 4.19 ( 82FC + a VM) kJ/kg Where FC and VM are the % values on dry ash free basis and a is an empirical constant which depends on the VM content of coal . VM 5 10 15 20 25 30 35 38 40 a 145 130 117 109 103 98 94 85 80

42. DULONG FORMULA HV = 338.2C + 1442.8(H - O/8) + 94.2 S kJ/kg Where C, H, O and S are the % of these elements on dry ash free basis . HEATING VALUE FROM ULTIMATE ANALYSIS Moisture : 8.12 % Ash : 17.71 % Carbon : 55.29 % Hydrogen : 3.11 % Oxygen : 13.37 % Nitrogen : 1.25 % Sulphur : 1.15 %

43. This experiment shall comply IS:1350- II (1970) Solid /liquid samples can be analyzed 1 g air dried sample is burnt in a bomb in oxygen atmosphere The oxygen pressure is 25 kg/cm 2 (Formation of water) Rise in temperature gives the heat liberated and heating value is determined after doing the corrections for resistance wire and thread Microprocessor based bomb calorimeters are now available EXPERIMENTAL DETERMINATION OF HEATING VALUE

44. BOMB CALORIEMETER Beckmann thermometer 0.001 o C accuracy, 1905

45. BOMB OF CALORIEMETER

46. VARIOUS COMPONENTS OF BOMB CALORIMETERIC EQUIPMENT

47. ROUTES OF GENERATION OF HEAT AND POWER FROM COAL

48. ROUTES OF GENERATION OF HEAT AND POWER FROM COAL Direct use as thermal energy in heating processes, furnaces and domestic heating by open fires Transfer of the heat to a thermal fluid and application of the latter for heating and power e.g., steam for heating in process industry, central heating and electricity generation by steam turbines Gas turbine route to electricity generation Conversion to gas/liquid fuels and subsequent usage in IC engines/turbines (gas/steam)

49. Domestic cooking ( Chulha at Tea stalls, Dhaba , Bakery) Space heating (Fireplace) Lime and brick kilns (Direct heating ) Ceramic industry (Oven/Furnace) ROUTE I (DIRECT HEATING)

50. Generation of steam in a boiler Space heating by transferring heat of steam to air Process industry: Cogeneration is employed Utility services: steam turbines used GOVERNMENT ALLOWED ELECTRICITY GENERATION BY PRIVATE DEVELOPERS Tariff : Electricity purchase rate- Rs /kWh Wheeling: through grids - December 31, 2013 – One nation, one grid and one frequency .(765 kV line, 440 kV, 220 kV) Power Grid Corporation of India. Banking SUPERCRITICAL BOILERS: A RECENT CONCEPT Critical pressure: 218 bar (21.8 MPa ), Critical temperature: 374 o C Mark Benson, in 1922 patent was granted 22 MPa pressure ; η = 1-T 1 /T 2 ≈ 0.53 ROUTE II (THERMAL FLUID)

51. ELECTRICITY GENERATION USING STEAM TURBINE WATER TO COOLING TOWER TURBINE EXAHAUST ELECTRICITY TO GRID WATER (COOLING) ALTERNATOR STEAM TURBINE CONDENSER COAL BOILER AIR FLUE GASES BHEL, Triveni and others Supercritical boilers P=218 atm T=374 o C Babcock and Wilcox: 1867 Benson: 1922 SCB:1957 Material of construction, CNG

52. ROUTE III (GAS TURBINE) VENT TURBINE EXAHAUST ELECTRICITY TO GRID ALTERNATOR GAS TURBINE HEAT EXCHANGER COMPRESSOR PULVERIZER COAL COMBUSTION CHAMBER AIR PREHEATED AIR

53. ROUTE III ( contd …) VENT TURBINE EXAHAUST ELECTRICITY TO GRID ALTERNATOR GAS TURBINE HEAT EXCHANGER COMPRESSOR COMBUSTION CHAMBER AIR PREHEATED AIR GASIFIER AND GAS CLEANING UNIT COAL

54. ROUTE IV (PYROLYSIS and GASIFICATION) Partial gasification or pyrolysis or coking or carbonization or destructive distillation (heating in the absence of air) Solid Liquid Gas Complete gasification with air/oxygen and steam Gas

55. PYROLYSIS Medium temperature carbonization (700-900 o C ) Liquid fraction for chemicals recovery/liquid fuel High temperature carbonization > 900 o C Coke for metallurgical furnaces; gas yield high; liquid low Low temperature carbonization (500-700 o C ) Coke (solid fuel) maximum; Classical domestic smokeless fuel production

56. PYROLYSIS ( contd …) PYROLYSER COAL WATER IN WATER OUT GAS FOR IC ENGINES/ GAS TURBINES/ THERMAL APPLICATIONS COKE FLUE GAS PRETREATMENT UNIT LIQUID FRACTION COAL TAR LIQUID FUELS CHEMICALS - ammonia, (ammonium nitrate, ammonium sulphate , ammonium phosphate) benzene, phenol, naphtha, pyridine, naphthalene, anthracene , cresylic acid toluene, xylene, CONDENSER GAS FOR HEATING OF PYROLYSER AIR

57. GASIFICATION MAIN OBJECTIVE IS TO PRODUCE SYN GAS or earlier when HCs based gaseous fuels were not there REASON: CHEMICALS (Ammonia, Urea and other fertilizers, explosive (Ammonium nitrate), AND LIQUID FUELS PRODUCTION (F-T process)

58. GASIFICATION REACTIONS Gasification with Oxygen C + 1 / 2 O 2 CO Combustion with Oxygen C + O 2 CO 2 Gasification with Carbon Dioxide C + CO 2 2CO Gasification with Steam C + H 2 O CO + H 2 Gasification with Hydrogen C + 2H 2 CH 4 Water-Gas Shift CO + H 2 O H 2 + CO 2 Methanation CO + 3H 2 CH 4 + H 2 O Coal Oxygen Steam Gasifier Gas Composition ( Vol %) H 2 25 - 30 CO 30 - 60 CO 2 5 - 15 H 2 O 2 - 30 CH 4 0 - 5 H 2 S 0.2 - 1 COS 0 - 0.1 N 2 0.5 - 4 Ar 0.2 - 1 NH 3 + HCN 0.0 - 0.3 Ash/Slag COS: Carbonyl Sulfide Heating value: 15-20 MJ/Nm 3 With air gasification: 4-5 MJ/Nm 3

59. Moving Bed Entrained Flow Fluidized Bed TYPES OF THE GASIFIERS

60. Oxygen Blown Entrained Flow Texaco E-GAS Shell Eastman Noell Fluidized Bed HT Winkler Foster Wheeler Moving Bed British Gas Lurgi Sasol Lurgi Transport Reactor Kellogg Air Blown Fluidized Bed HT Winkler IGT “ Ugas ” KRW Foster Wheeler Spouting Bed British Coal Foster Wheeler Entrained Flow Mitsubishi Transport Reactor Kellogg Hybrid (Moving bed +) Foster Wheeler British Coal ENERCON FERCO/Silva MAJOR PLAYERS IN GASIFIERS

61. (Air Separation Unit) ENTRAINED BED

62. ROUTE IV Bergius process Friedrich Karl Rudolf Bergius (Germany) in 1913 Nobel Prize in 1931 (Shared with Carl Bosch) By end of World War II – most of the liquid fuel for German army was produced by this method. Hydrogenation of vegetable oils Fischer- Tropsch process Franz Fischer and Hans Tropsch in 1926, Germany Coal is hydrogen starved/hydrogen needs to be added to make it liquid (directly or indirectly)

63. BERGIUS PROCESS PULVERIZER COAL PASTING UNIT HYDROGEN COAL BERGIUS REACTOR HEAVY FRACTION HCS T = 400 - 500 o C P = 20 - 70 MPa CATALYST = TIN η = 97% FRACTIONATING COLUMN

64. FISCHER-TROPSCH (F-T) PROCESS GASIFICATION UNIT SYN GAS CLEANING COAL F-T REACTOR HCS T = 150 - 200 o C P = 1 - 25 MPA CATALYST = IRON OR COBALT BASED FRACTIONATING COLUMN SYN GAS ( Large number of patents worldwide )

65. F-T PROCESS (COMMERCIAL PLANTS) SASOL Afrikaans: Suid Afrikaanse Steenkool en Olie , English: South African Coal and Oil Established in 1950 Oldest plant producing petrol and Diesel profitably from coal and natural gas using Fischer- Tropsch (F-T) process Presently engaged in Qatar, Iran and Nigeria in similar projects

66. F-T PROCESS (COMMERCIAL PLANTS) (cont…)

67. Players in this area of Gas To Liquid (GTL) GE Exxon Shell BP Chevron Sasol With crude touching the $ 140+, these two technologies would be economically viable. F-T PROCESS

68. A process applied to the non-mined coal seams Injection and production wells are drilled End gas mix depends on type of coal seam Air/oxygen can be used for gasification Syn gas can be used for power generation in combined cycle Syn gas can be converted to chemicals/fuel by F-T process UNDERGROUND/IN SITU COAL GASIFICATION

69. Source: World Coal Institute UNDERGROUND/IN SITU COAL GASIFICATION

70. Carbon capture and storage, alternatively referred to as carbon capture and sequestration, is a means of mitigating the contribution of fossil fuel emissions to global warming The process is based on capturing CO 2 from large point sources, such as fossil fuel power plants, and storing it in such a way that it does not enter the atmosphere. CO 2 CAPTURE AND SEQUESTRATION

71. Sequestration Gaseous and supercritical storage in various deep geological formations (including exhausted gas and oil fields and coal seams which are unrecoverable) Liquid storage in the ocean Solid storage by reaction of carbon dioxide with metal oxides to produce stable carbonates Capture Proven technology being used in process industries and power plants BUT THE COST IS THE DECIDING FACTOR CO 2 CAPTURE AND SEQUESTRATION ( contd …)

72. END