为脱除高含氮天然气中氮气，获得满足商品气指标的天然气，采用C₅作为吸收剂在低温下吸收天然气中的甲烷，利用HYSYS软件对冷油吸收工艺过程中温度、压力、溶剂循环量以及吸收塔板数进行研究分析，同时采用多指标正交模拟试验考察工艺参数对甲烷回收率、净化气氮气含量以及过程功耗等工艺指标的影响程度，并通过综合平衡法优选出较优方案。结果表明，当温度为-20℃、压力为3.5 MPa、循环量为5 000 kmol/h、塔板数为14时可达到较好的处理效果。

In order to remove nitrogen from high nitrogen-containing natural gas to meet commercial gas specifications,C₅ is used as an absorbent to absorb methane in natural gas at a low temperature,and the temperature,pressure,solvent circulation amount and the number of absorber trays of the cold oil absorption process are studied and analyzed by HYSYS software.Meanwhile,multi-index orthogonal simulation test is used to explore the influences of process parameters on the methane recovery rate,nitrogen content in purified gas and process power consumption.A better solution is selected by comprehensive balance method.The results show that the treatment effect will be better when the temperature is -20℃,the pressure is 3.5 MPa,the circulation amount of solvent is 5 000 kmol per hour and the number of plate is 14.

马国光(1964-),男,博士,副教授,主要从事天然气的集输与处理、LNG技术等研究工作