含氧煤层气流量变化对液化工艺影响的模拟研究

Simulation Study on Influence of Flow Change of Oxygen-contained Coal-bed Methane upon Liquefaction Process

利用HYSYS软件对煤层气液化工艺进行模拟计算,分析了煤层气流量变化对液化能耗和CH4回收率的影响,结果表明:总液化能耗变化幅度与煤层气流量变化幅度一致,其中氮气压缩功耗变化幅度大于流量变化幅度,混合冷剂压缩功耗变化幅度小于流量变化幅度;煤层气流量变化会使LNG单位产品液化能耗增加,但流量减小不影响CH4回收率,只有流量增加会降低CH4回收率。在实际运行时,应使制冷系统提供的冷量留有5%的余量,以确保工艺过程的安全与稳定。

In this paper, simulation calculation wad carried out on the liquefaction process of coal-bed methane by using HYSYS software and analysis was made on influence of the flow change of coal-bed methane upon the energy consumption of liquefaction and the recovery rate of methane. The results showed that the change range of the total liquefaction energy consumption was identical with that of coal-bed methane flow, of which the change range of the nitrogen compression energy consumption was greater than that of coal-bed methane flow and that of the MRC compression energy consumption was smaller than that of coal-bed methane;the flow change increased the liquefaction energy consumption of unit LNG product, but the flow decrease did not affect the recovery rate of coal-bed methane, and only the flow increase may reduce its recovery rate. In actual operation, it’ s better to make the cooling system having 5% margin so as to ensure the security and stability of the liquefaction process.