Abstract:
A gas injection apparatus with a controllable gas injection point, a gas injection process, and a gasification method. The gas injection apparatus comprises a directional well channel, where a continuous oil pipe is provided in the directional well channel. The continuous oil pipe is connected to an oxygen/oxygen-rich gas pipeline. An annular gap between the continuous oil pipe and the directional well channel is connected to an auxiliary gasification agent pipeline and a vapor pipeline. A gas injection wellhead is provided at the start end of the continuous oil pipe, and a nozzle is provided at the tail end. In the present invention, based on directional drilling and continuous oil pipe technologies, the movement of a gas injection point is implemented by using a manner of combining directional drilling and a continuous oil pipe; meanwhile, by using a principle of controlling reverse combustion by adjusting a gasification agent injection parameter, the movement of a working surface position and a combustion speed of a flame are regulated, so as to achieve the objective of ignition and gasification for reverse combustion of an underground coal layer.