基于Aspen Hysys的沼气中N_2对净化工艺的影响

Study on Effect of N_2 on Biogas Purification Process Based on Aspen Hysys

沼气净化技术主要包括脱硫、脱水、脱碳等工艺,而很少涉及N_2对净化工艺的影响。系统地研究了沼气中氮含量对其净化效果的影响。利用化工过程模拟软件,对沼气虚拟临界性质、热值、定压比热容等进行了物性分析,以及对压缩机功耗进行了模拟计算。研究发现,随着N_2含量从0%增至9%时,沼气的临界温度下降12.53℃,热值下降9.03%;N_2含量的增加,也使得在脱碳工序中,对沼气进行冷却降温时所需的换热量增加,且冷却效率明显降低;在相同排气压强工况下,随着N_2含量的增加,压缩机功耗增加明显。

The effect of N2 content in biogas on purification efficiency was studied systematically. By the chemical simulation software, the virtual biogas critical properties, calorific value, specific heat capacity at constant pressure and the compressor power consumption were calculated and analyzed. The results showed that when the content of N2 increased from 0% to 9%, the critical temperature of biogas decreased by 12.53 ℃ and the calorific value decreased by 9.03%. As a result of the increase of N2 content, the quantity of heat exchange used for cooling biogas increased in the stage of decarburization,and the power consumption of the compressor also increased obviously under the same exhaust pressure condition.