The invention relates to a
coal underground gasification process
system. The
coal underground gasification process
system comprises a gasification agent injection
drill hole,
coal gas outlet
drill holes, a main gasification channel,
branch gasification channels, a
drill hole supporting tube, a gasification agent injection tube, a
combustion agent injection tube, a sealing device and an
ignition point shifter. The gasification agent injection
drill hole is connected with the
coal gas outlet drill holes through the main gasification channel and the
branch gasification channels, and the
combustion agent injection tube is sleeved with the gasification agent injection tube and is connected through the sealing device. A gasification process includes the steps of carrying out ignition, judging whether
water vapor is fed into, feeding into
water vapor, judging whether an
ignition point is moved forward, starting the
ignition point shifter and continuing to conduct
combustion. The coal underground gasification process
system has the advantages that the transverse gasification area and longitudinal gasification area can be enlarged, coal reserves for gasification are increased, autoignition and controllable back gas injection are achieved in a well-free coal underground gasification process, meanwhile the problem of
short circuit of gasification agents in the gasification channels is solved, the probability of back mixing of
product gas and the gasification agents is lowered, and safety operation of the gasification process is guaranteed.