  Coalbed methane embedded in coal seams, is an unconventional energy resource
as well as a hazardous gas existing in mining industries, which attracts lots
of global attention. As the largest coal producer, the mining industry in China
had to deal with many hazards induced by methane for decades. To solve this
issue, underground methane extraction is commonly used in underground coal
mines. However, underground methane extraction is hampered by low production
rate and low efficiency because of slow gas emission from coal primarily
controlled by gas desorption and permeability. It is well known that
temperature has a great impact on gas sorption. The higher the temperature the
larger the desorption rate. As the depth of coal mines increases beyond 1000m
coal mines suffer elevated air temperatures caused by the natural geothermal
gradient. The elevated temperature in such mines provides a potential
economical way for geothermal energy extraction and utilization in deep coal
mines which can largely cut the expenses of installation and operation
maintenance. Therefore, a novel method is proposed to enhance underground
methane extraction by deep heat stimulation. This paper mainly presents an
assessment of previous and ongoing research in the related field and provides a
first feasibility analysis of this method applied in the underground
environment. The technique proposed in this early appraisal is deemed
significant for coalbed methane drainage enhancing the productivity of deep
coal mines by geothermal technology and can also be extended for many
applications in relevant areas such as shale gas, and tight oil.
