For the development of deep water gas fields, it is an important technology to inject hydrate inhibitors such as monoethylene glycol (MEG) into gas pipelines and to re-claim and reuse it to prevent gas hydrate. When the content of divalent metal saline in the produced water is high,a MEG regeneration unit cannot work well for the blocking,scaling and corrosion in the pipeline or the conventional MEG regeneration unit. Therefore a new process of MEG regeneration was developed, in which bivalent cations could be removed through filtering the precipitates formed by injecting alkaline solutions, and then the softened rich MEG solutions were transmitted to a regeneration column to regenerate and recovery. By simulation experiments, the influencing factors and operating conditions of bivalent cat-ions removal from rich MEG solutions were investigated and analyzed. The results showed that the best operation conditions were total dosage of alkali of 14.9 mL/L (wherein the NaOH dosage was 4.3 mL/L, Na2CO3 dosage was 10.6 mL/L), the reaction temperature of 55 ℃, residence time of 10 min, stirring speed of 180 r/min. Under this condition, the concentration of M2+ in the rich MEG solutions was reduced from 881 mg/L to 0.480 7 mg/L with the removal rate of 99.95%,which could meet the scaling prevention demands.%向天然气管道中注入乙二醇并进行回收再利用是深水气田开发中防止水合物生成的重要技术手段，但当采出水中的二价盐含量较高时会造成管道或MEG再生系统的堵塞、结垢和腐蚀等问题，导致常规乙二醇再生系统不能正常生产。为此开发了一种新的乙二醇再生工艺，即在MEG富液中加入碱液使M2+生成沉淀物，然后采取过滤分离的方式脱掉二价盐再进行再生。通过室内模拟实验，对富乙二醇中二价阳离子脱除影响因素和操作条件进行了研究，结果表明：加入NaOH溶液（50%）、Na2CO3溶液（20%）时的最佳操作条件为碱液总加量14.9 mL/L （其中NaOH溶液加量为4.3 mL/L， Na2CO3溶液加量为10.6 mL/L），反应温度55℃，停留时间10 min，搅拌速度180 r/min。在此条件下，模拟MEG富液中M2+浓度由881 mg/L降至0.4807 mg/L，脱除率达99.95%，能满足防垢需求。
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