基于活性炭的真空变压吸附提浓煤层气甲烷的实验研究

测试了活性炭的平衡吸附特性，在此基础上研究筛选出了适合煤层气提浓的活性炭，其比表面积为1 706 m2/g，并建立了两塔真空变压吸附提浓煤层气甲烷的实验装置，对甲烷体积分数为20%的低浓度煤层气提浓进行了实验。结果表明：利用真空变压吸附的方法，吸附压力在209 kPa以内，解吸压力为21 kPa时，可以将体积分数为20%的煤层气提浓到30%以上且产率超过80%；适当的延长吸附时间有助于提高甲烷的体积分数；降低解吸压力有助于提高甲烷的体积分数和产率；均压有助于提高甲烷的体积分数，既有上均压又有下均压的均压过程对甲烷体积分数的增大效果最好，实验中下均压02 s、上均压04 s时甲烷体积分数最大；维持吸附时间不变，存在一个最佳的产品气与原料气之比（Qc/Qin），使得甲烷体积分数达到最大值。

The experimental study on upgrade of coal mine gas by vacuum pressure swing adsorption with activated carbon

The equilibrium adsorption characteristics of activated carbon had been tested, On this basis, the suitable activated carbon for coal-bed methane purification had been selected. The experimental study was carried out in order to upgrade the concentration of coal mine gas by vacuum pressure swing adsorption process. The results show that the methane concentration of coal mine gas can be concentrated from 20% to above 30% by using activated carbon as adsorbent.In the process, increasing adsorption time can increase methane concentration,mean while decreasing desorption pressure helps to increase concentration and recovery of methane. Besides, to improve the methane concentration, pressure equalizing is helpful to improve the methane concentration, especially when pressure equalizing at both ends of the absorber. The optimal equalization step is the step.with equalization time of 0.2s at the inlet end and equalization time of 0.4s at the outlet end. Further more , maintaining the adsorption time constantly, there is an optimum ratio between product flow rate and feed flow rate , making the concentration of methane reached the maximum.