Page 200 - Advances In Productive, Safe, and Responsible Coal Mining

Coal mine methane: Control, 10

utilization, and abatement

Satar Mahdevari
Hamedan University of Technology, Hamedan, Iran

10.1 Introduction

Coal, as the most abundant and economical fossil fuel, has been an important source of
global primary energy production for the past two centuries, and will continue to be an
essential component of the global energy mix for the next few decades. Without coal
resources, the United Nations’ development goals are not achievable [1]. Total min-
able reserves of coal to a depth of 1000m (3300ft) are estimated at 1 trillion tonnes
(1.1 trillion tons), while estimated reserves to a depth of 3000m (10,000ft) range from
17 to 30 trillion tonnes (19–33 trillion tons) [2]. Total known mineable coal deposits
are sufficient for at least 300years of use, a timeframe that is approximately fivefold
that of known natural gas resources and tenfold that of known crude oil resources.
Approximately 60% of world steel production and 40% of current electricity produc-
tion are powered by coal. Historically, coal has played a significant role in the
advancement of civilization, and it will continue to be a major fuel source in devel-
oping countries for at least the next quarter century [3]. Coal is, therefore, central to
the energy security of many countries and will continue to play a significant role in
ending energy poverty around the world.
World coal production in recent years has reached almost 8 billion tonnes (9 billion
tons) per year. At this rate, coal and the associated methane gas that is released are
likely to remain a dominant source of energy in coming decades; however, it will
not be without some resistance due to the debate regarding climate change. Despite
the swift deployment of renewable energy, mainly in response to that debate, coal
has been responsible for the largest upsurge in meeting energy requirement of all
energy sources. To maintain that position, it is imperative that the industry implement
modern mining principles in planning, designing, and extracting coal to control, uti-
lize, and abate vented and leaked methane gas.
Coal seams are formed over millions of years by the biochemical decay and meta-
morphic transformation of plant materials. When plant materials such as roots, bark,
and wood are deposited in swampy lakes, they undergo bacterial and chemical
changes to make peat deposits. Coalification results as these deposits are subjected
to high pressure and high temperature over time. The coalification process produces
large quantities of byproduct gases such as methane (CH 4 ) and carbon dioxide (CO 2 ).
The chemical composition of coal is therefore determined by its derivation from plants
and comprises carbon, hydrogen, and oxygen, with nitrogen and sulfur as minor

Advances in Productive, Safe, and Responsible Coal Mining. https://doi.org/10.1016/B978-0-08-101288-8.00010-9
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