降低页岩气脱水溶液损失的措施

Measures to reduce the loss of dehydrated solution in shale gas

在页岩气溶液吸收法脱水工艺中,溶液损失是工艺设计和操作的关键控制参数,如果损失较大,一方面会导致产品气中携带过饱和雾状液滴,在输送过程中由于压力、温度、流速、流态、管道腐蚀等发生变化而以固体杂质的形态析出,对下游管道、阀门造成颗粒冲刷,严重时甚至发生堵塞;另一方面需要不断向脱水系统补充新鲜溶液,大大增加了脱水处理的运行成本。为分析溶液损失的影响因素,找到降低溶液损失的有效措施,对整个工艺过程中可能造成溶液损失的物流进行了物性研究、工程模拟、操作条件变换,探求出影响趋势。研究结果显示,降低溶液损失的措施包括原料气应选择适宜的温度和压力、对原料气中的杂质进行深度预处理、在吸收塔气体出口的下游设置高效气液聚结器、合理设置重沸器温度测温点位置、再生系统选取适宜的气提气量。研究结果为降低页岩气脱水溶液损失提供了借鉴。

In the shale gas dehydration process using solution absorption,the loss of absorption solution is the key control parameter for design and operation of this process.If the loss is large,on the one hand,the product gas will carry over the solution mist droplets.Precipitation would occur in the form of solid impurities due to changes in pressure,temperature,flow rate,flow pattern and pipeline corrosion during the gas transportation process,causing particle erosion and even blockage of downstream pipes and valves.On the other hand,the loss of absorption solution requires the continuous fresh replenishment,which greatly increases the operating cost of the dehydration operation.In order to analyze the factors causing solution loss and find out the effective measures to reduce loss,physical property research,engineering simulation,operating condition changes are carried out.Some measures to reduce solution loss are proposed,such as selecting optimum temperature and pressure of raw gas,deep pretreatment of impurities in the raw gas,installing high efficiency gas-liquid filter downstream of the gas outlet of the absorber,selecting optimum location of temperature measuring point for reboiler temperature,selecting suitable stripping gas volume in the regeneration process.The research findings provide a good reference for ways to reduce absorption solution loss via carryover from the dehydration system.