含氧煤层气吸附脱水再生气的选择

Regeneration gas of oxygen-bearing coal mine methane by adsorption and dehydration

对含氧煤层气进行深冷精馏回收甲烷,需要利用分子筛对其进行深度脱水。从安全性和经济性角度考虑,对不同甲烷摩尔分数的煤层气和不同液化精馏工艺流程设计,再生气的选择也有所不同。液化精馏过程中甲烷回收率大于98%,则可以选择精馏放空尾气作为再生气;对甲烷回收率较低的工艺,若煤层气中甲烷摩尔分数大于27.5%,可选择原料煤层气作为再生气,但应在常压下进行再生并严格控制再生加热过程。

To recover methane from oxygen-bearing coal mine methane,deep dehydration step is necessary by using molecular sieve.From the security and economic point of view,the selection of regeneration gas is greatly dependent on the concentration of methane in the coal mine gas and liquefaction distillation process.If the recovery rate of methane in distillation process is greater than 98％,the distillation exhaust can be used as resurgent gas.In contrast,for low methane recovery rate process （less than 27.5％）,the oxygen-bearing coal mine gas can be directly used as resurgent gas,but it should be carried out under normal pressure and strict control of the heating process.