天然气提氦工艺模拟与分析

Simulation and analysis on natural gas helium-extraction process

为降低能耗的同时提高天然气提氦工艺回收率和粗氦产品体积分数,提出了基于低温精馏原理的天然气提氦流程,该流程具有设备少、回收率高、粗氦产品体积分数高以及能耗低的特点。利用HYSYS软件建立了天然气提氦模型,并对一次提氦塔塔压、一次提氦塔塔顶进料温度、二次提氦塔进料温度等关键参数进行了分析,确定了较优的工艺参数,在回收率为95%、粗氦产品体积分数为75%的条件下,总能耗为425 kW。最后采用分析方法定量地确定了流程中各设备的损失大小,为流程改进指明了方向,其中损失最大的设备是冷箱,其次为压缩机,第三是水冷器,第四是节流阀,第五是精馏塔,混合器损失最小。

In order to reduce energy consumption,improve the recovery rate of helium by natural gas helium-extraction process and increase the purity of crude helium,a natural gas helium-extraction process based on cryogenic rectification principle is proposed.This process needs less equipment and energy consumption,and can obtain a high recovery rate and high purity of crude helium.A natural gas helium-extraction model is established by using HYSYS software,and key parameters are analyzed,including the pressure of the primary helium-extraction tower,the top feed temperature of the primary helium-extraction tower,and the feed temperature of the secondary helium-extraction tower.The optimal process parameters are determined.Total energy consumption is 425 kW when the recovery rate of helium is 95%and the purity of crude helium is 75%.The exergy analysis method is employed to quantitatively determine the exergy loss of each device in the process,which points out the direction for process improvement.