Heat stable salts (HSS) are well-known degradation products of gas desulfurization using N-methyldiethanolamine (MDEA) solvents. Excessive HSS content causes a decrease in desulfurization efficiency, a decrease in the active ingredients of MDEA, and the corrosion of pipelines. In this paper, a self-designed two-compartment electrodialysis (ED) stack, a three-compartment electrodialysis (TED) stack, and an anion exchange resin coupled three-compartment electrodialysis (RTED) stack were assembled to remove the HSS from spent MDEA wastewater. The HSS desalination mechanisms of the three electrodialyzers were investigated, and their HSS removal efficiencies and losses of MDEA were investigated and compared. According to the results, approximately 93.84% of HSS were removed from the spent MDEA wastewater in the RTED, 7.88% higher than those in the TED and 28.57% higher than those in the ED. The loss of MDEA for the RTED was 3.78%, which is 1.78% lower than that for the TED and 17.29% lower than that for the ED. A relatively high sodium hydroxide (NaOH) concentration in the NaOH compartment, but no more than 3%, is beneficial for both improving the HSS removal efficiency and decreasing the loss of MDEA in TED and RTED. Much less fouling of the anion exchange membranes occurs in the RTED process than in the ED process because of the effect of the filled resin and the NaOH compartment. The cost of RTED is estimated to be US $0.88/kg HSS, which is far lower than that of both ED and TED.

热稳定盐（HSS）是使用N进行气体脱硫的众所周知的降解产物-甲基二乙醇胺（MDEA）溶剂。HSS含量过多会导致脱硫效率下降，MDEA活性成分下降以及管道腐蚀。本文组装了自行设计的两室电渗析（ED）堆栈，三室电渗析（TED）堆栈和阴离子交换树脂偶联的三室电渗析（RTED）堆栈，以从用过的MDEA中去除HSS废水。研究了三台电渗析器的HSS脱盐机理，并比较了它们的HSS去除效率和MDEA损失。根据结果​​，RTED中从MDEA废废水中去除了约93.84％的HSS，比TED中的高7.8％，比ED中的高28.57％。RTED的MDEA损失为3.78％，比TED低1.78％，比ED低17.29％。NaOH隔室中较高的氢氧化钠（NaOH）浓度，但不超过3％，对于提高HSS去除效率和减少TED和RTED中MDEA的损失都是有益的。由于填充树脂和NaOH隔室的影响，与ED工艺相比，RTED工艺中阴离子交换膜的结垢更少。RTED的成本估计为0.88美元/千克HSS，远低于ED和TED的成本。由于填充树脂和NaOH隔室的影响，与ED工艺相比，RTED工艺中阴离子交换膜的结垢更少。RTED的成本估计为0.88美元/千克HSS，远低于ED和TED的成本。由于填充树脂和NaOH隔室的影响，与ED工艺相比，RTED工艺中阴离子交换膜的结垢更少。RTED的成本估计为0.88美元/千克HSS，远低于ED和TED的成本。