膜法去除海上气田乙二醇富液中二价阳离子的研究

Study on removal of calcium and magnesium ions from ethylene glycol rich solution in offshore gas field by membrane method

为了解决海上气田乙二醇富液中Ca^(2+)、Mg^(2+)难以去除的技术难题,本文采用陶瓷无机超滤膜对高含盐的乙二醇富液进行分离处理,考察了工艺条件对处理效果的影响。结果表明,在跨膜压差为0.06MPa,膜面流速为5.6m·s^(-1),温度为80℃,连续运行120h的条件下,膜通量稳定在200L·(m^(2)·h)^(-1)以上,处理后的富乙二醇悬浮物固含量小于0.829mg·L^(-1),粒径中值小于1μm,膜过滤液Ca^(2+)、Mg^(2+)含量小于0.19mmol·L^(-1),二价盐脱除率大于99.8%;通过化学药剂清洗,膜性能几乎完全恢复。

In order to solve the technical problem of difficult removal of divalent cations in rich MEG of offshore gas field,ceramic inorganic ultrafiltration membrane was used to separate the rich solution of ethylene glycol with high salt content,and the influence of process conditions on the treatment effect was investigated in this paper.The results show that under the condition of transmembrane pressure difference of 0.06MPa,membrane surface velocity of 5.6m·s^(-1)and temperature of 80℃,the stable flux of membrane is more than 200L·(m^(2)·h)^(-1),the content of salt particles is less than 0.829mg·L^(-1),and the median particle size is less than 1μm,and the calcium and magnesium content of membrane filtrate is less than 0.19mmol·L^(-1),and the removal rate of divalent salt is more than 99.8%.Through chemical cleaning,the performance of the membrane is almost completely restored.