重叠步骤对真空变压吸附制氧性能的影响

Effects of overlap steps on oxygen production by vacuum pressure swing adsorption

建立了一套半工业性两塔真空变压吸附制氧试验装置,提出了2种循环操作时序,循环一的特征在于具有同时逆向抽真空与清洗、同时逆向抽真空与均压升2个重叠步骤;循环二具有同时逆向抽真空与清洗、同时进气升压与均压升2个重叠步骤。试验结果显示,采用13LiX沸石分子筛,2种循环流程获得体积分数为92.1%的氧气时,回收率分别达到58.9%和64.8%,氧气产率分别为80.9 m3/(h.t)和86.3 m3/(h.t)。在较低压比的情况下,2种不同循环流程均能获得较好的制氧性能,吸附塔的最高吸附绝对压力分别约为148 kPa和149 kPa,最高压比分别为3.44和3.39。

A two-bed vacuum pressure swing adsorptive（VPSA） oxygen production pilot plant is built to investigate the effects of overlap steps on its performance. Two various cyclic sequences are proposed. The first cycle comprises the steps of simultaneous countereurrent evacuation and receiving purge, simultaneous countercurrent evacuation and pressure equalization rising. The second cycle consists of simultaneous countercurrent evacuation and receiving purge step, as well as simultaneous feed repressurization and pressure equalization rising. The experimental results show that 02 of 92.1% purity can be achieved by either cycle which employs 13LiX zeolite. The 02 recovery rate are 58.9% and 64.8%, respectively. The 02 yield are 80.9 m^3/（h·t） and 86.3 m^3/（h·t）, respectively. The relatively satisfied performance can be obtained when the pressure ratio of system is lower. The maximum absolute adsorptive pressure for the two cycles are about 148 kPa and 149 kPa, respectively. Correspondingly,the pressure ratio are 3.44 and 3.39, respectively.