ucg t c patra india

Underground Coal Gasification

T C Patra Sr RE

INDIA


• COALIFICATION PROCESS

• GASIFICATION PROCESS

• UNDERGROUND (IN SITU) PROCESS

…. covers


COALIFICATION PROCESS

COALIFICATION

PROCESS IN

REDUCING

ENVIRONMENT


CHEMICAL COMPOSITION OF COAL

Fuel C H O N

Wood 49.65 6.23 43.20 0.92

Peat 55.44 6.28 35.56 1.72

Lignite 72.95 5.24 20.50 1.31

Bituminous 84.24 5.55 8.69 1.52

Anthracite 93.50 2.81 2.72 0.97

Clarke


CHEMICAL COMPOSITION OF COAL

Rank Moisture Vol.

Matter

Fixed

Carbon

Ash

Lignite 34.55 35.34 22.91 7.20

Sub-

Bituminous

24.28 27.63 44.84 3.25

Bituminous 3.24 27.13 62.52 7.11

Semi-

Anthracite

3.38 8.47 76.65 11.50

Anthracite 2.80 1.16 88.21 7.85

After Moore


INDIAN COAL


COAL PROVED RESERVES

Million Tonnes_End 2001_BP statistics


COAL PROD VS. CONSUMPTION

-

20.0

40.0

60.0

80.0

100.0

120.0

140.0

160.0

180.0

200.0

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

-

20.0

40.0

60.0

80.0

100.0

120.0

140.0

160.0

180.0

200.0Prod (Million Ton OE)Consumption (Million Ton OE)


WORLD PRIMARY ENERGY

CONSUMPTION

9124.8 594.5 601.2 2255.1 2164.3 3510.6 WORLD

335.2

5.8

38.7

84.4

74.6

131.6 Germany

514.5

20.4

72.7

103.0

71.1

247.2 Japan

643.0

39.8

30.9 114.6

335.4

122.3 Russia

314.7

16.1

4.4

173.5

23.7

97.1 India

839.7

58.3

4.0

520.6

24.9

231.9 China

2237.3

48.3

183.2

555.7

554.6

895.6 USA

Total Hydro

electric

Nuclear

Energy

Coal Natural

Gas

Oil Million

tonne oil

equivalent

India is the 3rd largest coal consumer of the world

R/P : 246 years


CARBON/COAL GASIFICATION

REACTIONS

Partial Combustion C + O2 = 2CO exothermic

Combustion C + O2 = CO2 exothermic

C + CO2 = 2CO endothermic

Water-Gas C + H2O = CO + H2 endothermic

Hydrogasification C + 2H2 = CH4 exothermic

Shift CO + H2O = CO2 + H2 exothermic

Reformation CO + 3H2 = CH4 + H2O exothermic


MATERIAL BALANCE

AIR GASIFICATION


MATERIAL BALANCE

AIR GASIFICATION

H2O - (153.9)

C - 1000

H - 79.6

O - 230.8

N - 13.3


MATERIAL BALANCE

GASIFICATION WITH O2+H2O liq


MATERIAL BALANCE

GASIFICATION WITH O2+H2O liq

H2O - (153.9)

C - 1000

H - 79.6

O - 230.8

N - 13.3


MATERIAL BALANCE

GASIFICATION WITH O2+H2O Steam

H2Oliq

1575.1 Kg


MATERIAL BALANCE

GASIFICATION WITH O2+H2O Steam

H2O - (153.9)

C - 1000

H - 79.6

O - 230.8

N - 13.3


UNDERGROUND COAL

GASIFICATION

A process to convert

unmineable under-ground

coal/ lignite into

combustible gases by

gasifying the coal insitu


ESSENTIAL STEPS IN UCG

• Drill wells into coal seam

• Create a permeable link

path

• Ignite coal at bottom

• Inject air (or oxygen) to

sustain fire

• Remove product gas

through production well

• Clean product gas in

surface facilities for end

use


.. where we STAND..

.. what we SEE..

.. what we FACE..

.. what we SEEK..


.. where we STAND..


UCG REACTORS - WORLD

Site Depth (m) Year Gas Produced

(Million m3)

Podmoskovna 30-80 1947-62 4700

Lissichamskaya - 1948-62

Angren 120-200 1962-current 14000

Juzno-Abinskaja 50-300 1955-current 6700

Schatska - 1965-74

*Russian Fields




(Million m3)

Hanna 85 1973-79 63.56

Hoe Creek 50-120 1976-79 12.18

Price Town 270 1979 1.39

Rawlins 30 1979-81 17.35

Centralia 75 1983 1.78

Hanna ( Rocky

Mt.1)

110 1987-88 13.10

USA fields




(Million m3)

Bruay-en-

Artois (France)

65 1978-81

La aute Deule

(France)

60 1979-85

Thulin

(Belgium)

860 1986-87 0.55

Alcorisa

(Spain)

500-700 1990 -

European fields


.. What we SEE..


WHY UCG IN INDIA

• Exploitation of huge unmineable

coal reserves (123 billion tonnes) in

Gujarat alone

• Transportation of coal to existing

power station: Severe strain on

railways

• Environmentally clean technology


WHY UCG IN INDIA

• Use of produced gas for power

generation or for chemical feed-

stocks

• Potential use of carbon di-oxide for

Enhanced Oil Recovery (EOR) exists

in the area


UCG POTENTIAL IN INDIA

POTENTIAL AREAS SOBHASAN, KALOL AND MEHSANA CITY STRUCTURE OF NORTH GUJARAT

ESTIMATED COAL/ 123 BILLION TONNES

LIGNITE RESERVES (700-1700 M DEPTH)

EXPECTED ENERGY EQUIVALENT TO ABOUT 15000 BILLION M3 OF NATURAL GAS (Meh-Ahm Block)


UCG POTENTIAL

GSI

234 Bt coal

(Around 150 Bt at

unmineable depth)

ONGC

>350 Bt (Unmineable depth)

63 Bt in

Mehsana-

Ahmedabad

Block

60 Bt in

Patan-

Tharad

Block

>200 Bt in

Bengal

Basin

Equivalent to

15000 Billion m3 of Natural Gas

10%

Equivalent to 1.35 times of

O+OEG reserves of ONGC


.. what we FACE..


EXPERIENCE IN UCG PROJECT

In mid 80’s a UCG National Committee was set up

to look into the UCG project wherein ONGC was

the nodal agency

• Proposed site was in Mehsana city structure

• Two Information wells were drilled

• Hydrological studies conducted

• Core studies conducted


EXPERIENCE IN UCG PROJECT

• 3-D Seismic survey carried out

• Prepared Geological model

• Design pilot wells


Proposed Site


GENERAL PROPERTIES FOR

FAVOURABLE UCG SITE

• Thickness of 3 to 10m

• Steeply dipping - (Flat lying acceptable)

• Strong, dry roof rock

• Coal seam shall not be major aquifer

• No major aquifer over coal seam at least twice of stable cavity height

• Low natural permeability of formation

• No major faults or fractures

• Amenable topography

• Proximity to end user market


UCG PILOT PROJECT IN INDIA

• PILOT PROJECT SITE : MEHSANA CITY

STRUCTURE

• TARGET COAL SEAM : SOBHASAN - III

• DEPTH OF COAL

SEAM : 900-1100 M

• THICKNESS OF COAL

SEAM : 6-14 M

• TYPE OF COAL : LOW RANK SOFT,

DARK BROWN

LIGNOBITUMINOUS



The objectives were: • To demonstrate the feasibility of UCG at deeper

depth

• To demonstrate drilling of long in-seam holes and to connect hole with vertical well

• To develop gasifier initiation and cavity growth control techniques

• To monitor and measure gasifier development

• To know product gas quality and quantity

• To prove material capabilities and environmental impact



The pilot could not be executed due to

• Limited expertise available then

• Non-availability of OIDB funds


PHYSICAL REQUIREMENTS

• Characteristics of coal/lignite seams (Chemical

analysis, pyrolysis, through tube coal

experiments)

• Characteristics of roof and floor rocks

(Mechanical properties for prediction of cavity

formation and subsidence)

• Hydrological studies and gas migration studies

• Pollution studies (Air and Water) before and after

gasification


TECHNOLOGICAL

REQUIREMENTS

• Drilling, Special cementing, Design and

Completion of Process wells

• Combustion process package ( Ignitor, Cavity

formation, Propagation)

• Process of CRIP (Controlled Retracting Injection

Point)

• Surface design for UCG


.. what we SEEK..


Participation Required

• Resource Characterisation

– Coal Seam Properties

– Hydrologic Characteristics

• Laboratory investigations of coal properties

• Laboratory Gasifier experiments

• Reaction Kinetics

• Subsidence studies

• Detailed Engineering design of pilot

• Development of process options for UCG product Gas cleanup.

• Simulation of underground process

…… and lot more

ucg t c patra india

Technology

bt coal

coal prod

coal seam

transportation of coal

largest coal consumer

h2o liq h2o

coendothermicwatergas

material balancegasification