Underground coal gasifier with air-lift point separating control and its process

Abstract

A separately controlled gas injection point coal underground gasifier and techniques, the method is achieved in the separately controlled gas injection point coal underground gasifier, the gasifier is installed with the wind hole (2) and wind tunnel (12), air gate (4) and the gas channel(6), oxygen tubes (3) are laid between the wind hole (2) and wind tunnel(12), the oxygen tubes (3) connects several certain distance separated of gas injection point controlling four-way pipe(8); a temperature sensor (13) is set at the four-way pipe position; blind hole (11)is set corresponding to the shutter A (25) and the shutter B (20) on the four-way pipe (8) position, along the coal bed both sides of the wind tunnel (12). The invention overcomes the coal wall combustion phenomena of bottom holes produced by the gasification of oxygen-enriched watered steam, avoid the wind tunnel plugging-up of bottom tunnels, ensure yield and quality of the gas; prevent the wind tunnel directly supply oxygen, guarantee the safety of gasification system; increase of controllability and stability of the gasification process through control to gas injection point and the corresponding loosened blind hole.

Description

technical field [0001] The invention belongs to the technical field of underground coal gasification, and in particular relates to an underground coal gasification furnace with separate control of gas injection points and a process method thereof, which is suitable for producing chemical synthesis gas and medium calorific value coal gas by oxygen-rich underground coal gasification. Background technique [0002] At present, air is used as the gasification agent in underground coal gasification production. Air gas has low calorific value and limited use. Using oxygen-enriched water vapor as gasification agent can significantly improve the gas composition, calorific value and the stability of the production process. . However, for the well-type "long channel, large cross-section" underground coal gasifier, the gasification of oxygen-enriched water vapor will cause coal wall combustion around the tunnel at the bottom of the borehole, causing the tunnel at the bottom of the boreh...

AI Technical Summary

Problems solved by technology

However, for the well-type "long channel, large cross-section" underground coal gasifier, the gasification of oxygen-enriched water vapor will cause coal wall combustion around the tunnel at the bottom of the borehole, causing the tunnel at the bottom of the borehole to collapse. In addition, if the air supply lane is used to directly supply oxygen, the pyrolysis gas generated by the coal seam due to heating will enter the air supply lane and mix with oxygen and explode, endangering the safety of the gasification system. Oxygen plus water vapor underground gasification currently has no field test and production examples in my country, that is, no feasible process and gasifier structure have been formed.

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