Methane, Gas Hydrates - GS questions based on daily current affairs

1)   Sweet Gas is

a. Gas with high amount of carbon monoxide
b. Gas with no or very low Hydrogen Sulphide
c. Gas with high amount of Carbon Dioxide
d. Gas with high amount of Nitrogen Dioxide
Answer  Explanation 

ANSWER: Gas with no or very low Hydrogen Sulphide

Explanation:

  • Sweet Gas is a Natural gas that does not contain hydrogen sulfide [H2S].
  • The gas may also not contain any quantities of carbon dioxide.
  • The composition of the gas determines whether it is sweet or sour.
  • Sweet Gas in its purest form can be used with very little refining. It is not corrosive in nature; hence it is relatively easy to use as compared to sour gas.
  • Coal Bed Methane is Sweet Gas


2)   Which of the following is/are true regarding Coalbed methane (CBM)?

1) The methane is in a near-liquid state.
2) The methane is stored within the coal due to a phenomenon called absorption.


a. Only 1
b. Only 2
c. Both 1 and 2
d. Neither 1 nor 2
Answer  Explanation 

ANSWER: Only 1

Explanation:

  • 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 (called the matrix).
  • The open fractures in the coal (called the cleats) can also contain free gas or can be saturated with water.
  • Gas contained in coal bed methane is mainly methane and trace quantities of ethane, nitrogen, carbon dioxide and few other gases.
  • Intrinsic properties of coal as found in nature determine the amount of gas that can be recovered.


3)   Which of the following is/are true regarding Coal Seam Gas?

1) It is produced from coal bed methane.
2) It contains very little heavier hydrocarbons such as propane or butane.


a. Only 1
b. Only 2
c. Both 1 and 2
d. Neither 1 nor 2
Answer  Explanation 

ANSWER: Only 2

Explanation:

  • 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.
  • In recent decades it has become an important source of energy in United States, Canada, Australia, and other countries.
  • The presence of this gas is well known from its occurrence in underground coal mining, where it presents a serious safety risk.
  • Unlike much natural gas from conventional reservoirs, coalbed methane contains very little heavier hydrocarbons such as propane or butane, and no natural-gas condensate. It often contains up to a few percent carbon dioxide.