Thomas chinnappan geologist keeranur, pudukkottai, tamilnadu, india.

1. COAL BED METHANE
EXPLORATION
BY:
THOMAS CHINNAPPAN . A ,
M.SC.APPLIED GEOLOGY,
PERIYAR UNIVERSITY,
SALEM.

2. INTRODUCTION
Coalbed methane (CBM or coal-bed
methane), coalbed gas, coal seam gas (CSG),
or coal-mine methane (CMM) is a form of natural
gas extracted from coal beds.

3. COAL BED METHANE
The term refers to methane absorbed into the solid matrix of the
coal. It is called 'sweet gas' because of its lack of hydrogen
sulfide.
The presence of this gas is well known from its occurrence in
underground coal mining, where it presents a serious safety risk.
Coalbed methane is distinct from a typical sandstone or other
conventional gas reservoir, as the methane is stored within the
coal by a process called adsorption.
The methane is in a near-liquid state, lining the inside of pores
within the coal.

4. COAL BED METHANE

5. HOW COAL BED METHANE IS FORMED?
• CMB is formed during the process of coalification, the
transformation of plant material into coal .
• It is considered a valuable energy resource with
reserves and production having grown nearly every year
since 1989.

7. CBM Gas Composition ;
The composition of CBM in a sample of coal varies widely
across several locations in the country.
 Generally, it consists predominantly of methane gas (CH4)
although it can contain trace amounts of ethane (C2H6), carbon
dioxide (CO2) and water (H2O).

8. METHANE GENERATION ;
CBM is generated by the conversion of plant material to coal
through burial and heating. As “coalification” progresses,
increasingly dense coal is formed, in order from low to high rank:
lignite, subbituminous, bituminous and anthracite.
Biogenic methane (attributed to bacterial activity) is first to form,
followed by thermogenic methane.
 Much of the methane generated by the coalification process
escapes to the surface or migrates into adjacent reservoir or other
rocks, but a significant volume remains trapped within the coal itself.

10. ENVIRONMENTAL IMPACTS ;
Disposal of water removed from coalbed methane
wells.
Drinking water level drop.
Contamination of aquifer.
Venting and seeping of methane and other chemical.
Air pollution.

12. INDIAN CBM RESERVES ;