Underground Coal Gasification Method

Abstract

The invention provides an underground coal gasification method, which includes constructing a directional horizontal channel located in a coal seam and sequentially arranging ignition holes communicating with it along the directional horizontal channel, at least two auxiliary holes, and a first directional hole to connect the directional horizontal channel Divide into continuous channel segment combinations in turn; ignite at the connection between the ignition hole and the directional horizontal channel; pass the combustion aid into the directional horizontal channel from the first directional hole to carry out reverse fire penetration through the channel segment combination in sequence, and this channel segment is the current through At the same time, the gasification agent is introduced into the current auxiliary hole connected with the current through section to carry out forward gasification on the channel section in the opposite direction to the forward direction of the reverse fire penetration, and this channel section is the current gasification section; the current auxiliary The hole is the auxiliary hole located at the end of the current through section away from the first directional hole among the at least two auxiliary holes, and the current gasification section is located at the end of the current through section. The invention provides a method capable of synchronously and continuously performing the reverse through process and the forward gasification process.

Description

Technical field [0001] The invention relates to the field of underground coal gasification, and more specifically, to a method for underground coal gasification. Background technique [0002] Underground coal gasification is a process of controlled combustion of underground coal, which produces combustible components under the action of heat and physical chemistry, and transports them to the ground. The non-well underground gasifier is formed by drilling holes from the ground to the coal seam, and directional drilling along the coal seam between the drill holes to open up the gasification channel. [0003] According to the different ways of gasification working face movement, it is divided into reverse penetration and forward gasification. Reverse penetration is to use air or low-concentration oxygen-enriched agent as a combustion-supporting agent, and send it to the fire area through directional holes or coal seam cracks at a low speed, so that the flame working surface moves in ...

AI Technical Summary

Problems solved by technology

Its disadvantages are as follows: firstly, the method of gasification after piercing is adopted, which leads to a long time for the gasifier to reach production; secondly, when a certain section is pierced, shrinkage cavities are likely to occur in other unpenetrated channels; thirdly, the water vapor generated during the piercing process cannot is effectively utilized, reducing the gasification efficiency

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