Air-contained coal gas gasification and separation process and equipment

Abstract

The present invention relates to an air-contained coal gas gasification and separation process, which is chiefly to passing over the air-contained coalbed gas to the middle of the fractionating tower after cooling, through the evaporation of the evaporator in the bottom of the fractionating tower and the condensation of the top condenser, gas fraction inside the inner of the tower, the sufficient quality and heat exchange of the liquid fraction. The high purity nitrogen gas is obtained in the top of the fractionating tower and the high purity liquid natural gas is obtained in the bottom of the fractionating tower, wherein one part of pure air is induced to the heat exchanger at the entrance between the top of the fractionating tower and the air-contained coalbed gas. The invention also provides an equipment of the separation process. The air-contained coal gas gasification and separation process and equipment are separation liquefaction process specially designed for the air-contained coalbed gas, which adopts the single stage rectifying still simpler than the doublestage rectifying, and has convenient operation, low cost and easy to popularize in large scale.

Description

technical field [0001] The invention relates to a gas liquefaction separation equipment and process, in particular to the liquefaction separation equipment and process of air-containing coal bed gas. Background technique [0002] Coalbed methane is also called unconventional natural gas or mine gas, and its main component is methane. It is not only a precious clean energy, but also an important chemical raw material. my country's coalbed methane resources are extremely rich, but the development is relatively small, and there is almost no industrial application. It is known that my country's coal-bed methane discharged into the atmosphere every year accounts for one-third of the total coal-bed methane emitted by coal mining in the world. This not only causes serious air pollution, but also wastes resources. [0003] The characteristic of coalbed methane is that the output of a single well is not very high. Except for the nearby use, it is often uneconomical to lay pipelines...

AI Technical Summary

Problems solved by technology

In particular, the coalbed methane extracted during the coal mining process has low pressure, low methane content, and air is mixed in it. Oxygen in the air is a dangerous combustion accelerant, which brings difficulties to the processing and transportation of coalbed methane. It is even more serious to empty and waste. This problem has not been well resolved.

In the previous methods, the separation purity is difficult to meet the requirements, some have low recovery rates, and some require heating. Air-containing coalbed methane is easy to explode at high temperatures, and there are potential safety hazards, so they have not been applied.

In the patent application filed by the applicant on May 19, 2006 titled "Airborne Coalbed Methane Liquefaction Process and Equipment", it was proposed to apply low-temperature rectification to the separation and liquefaction of airborne coalbed methane, and described a Two-stage rectification process, but this process method requires more equipment, the process is more complicated, and the input cost is higher, which is not conducive to the popularization and application of small-scale coal mines

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