基于HYSYS的C3/MRC天然气液化流程影响因素分析

Influence factors analysis of propane-mixed refrigerant natural gas liquefaction process based on HYSYS software model

关键词:  天然气液化  丙烷预冷  混合剂制冷  HYSYS  模拟计算 

Key words:  natural gas liquefaction  propane pre-cooling  mixed refrigeration  HYSYS  simulation

摘要:

丙烷预冷混合制冷剂液化流程投资省、流程简单、机组少,在基本负荷型液化装置中占主导地位。运用HYSYS软件对其进行模拟,分析出天然气压力、高低压混合制冷剂压力、混合制冷剂组成这4个流程参数对混合制冷剂的制冷能力和压缩机、水冷却器功耗的影响。模拟结果表明,提高天然气压力和减少混合制冷剂中甲烷含量,不仅能增强混合制冷剂的制冷能力,还可减少压缩机和水冷却器的功耗；提高低压制冷剂压力和降低高压制冷剂压力,虽然可降低压缩机和水冷却器的功耗,但会减弱混合制冷剂的制冷能力。提出了以增加混合制冷剂流量或减少混合制冷剂中甲烷含量的方式来弥补制冷能力降低的情况。

Abstract:

Propane-mixed refrigerant cycle dominates the base-load liquefaction plant for its advantages of saving investment, simple process and fewer units. The HYSYS simulation is carried out and the effects of process parameters, such as gas pressure, mixed refrigerant pressures and mixed refrigerant composition on the refrigerating capacity and energy consumption of the compressors and water cooler are analyzed. The simulation results show that:increasing the gas pressure and reducing the methane content of the refrigerant can not only enhance its refrigerating capacity but also reduce the energy consumption; and increasing the pressure of the low pressure refrigerant and decreasing the pressure of the high pressure refrigerant can reduce the energy consumption but weaken the refrigerating capacity. A scheme of enhancing the refrigerant flow and reducing the methane content is proposed to make up for the reduction of the refrigerating capacity.