醇胺溶液预碱洗性能的研究

摘要

对二甘醇胺(DGA)、二乙醇胺(DEA)、甲基二乙醇胺(MDEA)3种醇胺溶液的预碱洗性能进行了研究.实验结果发现,当质量分数为30％和20％的DGA的通入量/理论量均为5.3时,脱后油样中硫化氢性硫质量分数均为0,适当增加原料硫质量分数、空速,脱后硫化氢性硫质量分数仍为0;当质量分数为30％和20％的DEA的通入量/理论量均为20时,脱后油样中硫化氢性硫质量分数为0.5μg/g,且最多被脱至0.5μg/g;当质量分数为50％的MDEA的通入量/理论量为20时,脱后油样中硫化氢性硫质量分数为0.5μg/g,且最多被脱至0.5μg/g.虽然3种醇胺预碱洗后油品都不同程度带有碱性,但总的来说,二甘醇胺DGA的预碱洗效果最好,其次是DEA,这与DGA和DEA都是伯胺且碱性强相一致,MDEA是叔胺,碱性弱,在含量较大的情况下和DEA脱除效果相近.%The pre-caustic washing properties of different ethanolamine solutions such as diglycoamine (DGA),diethanoamine (DEA) and methyldiethanoamine (MDEA) are studied.The results of experiments show that,when the intake/theoretical value of DGA with concentrations of 30％ and 20％ is 5.3,the concentration of hydrogen sulfide sulfur in the feed is zero after desulfurization;When the sulfur content and space velocity of the feedstock are properly increased,the concentration of hydrogen sulfide sulfur in the feed is still zero after desulfurization;When the mass amount of DEA with mass concentration of 20％ and 30％/theoretical amount is 20,the concentration of hydrogen sulfide sulfur in the feed is 0.5 μg/g maximum.When the mass amount of MDEA with mass concentration of 50％/theoretical amount is 20,the concentration of hydrogen sulfide sulfur in the feed is 0.5 pg/g maximum.Although the oil after caustic washing by DEA,DGA and MDEA is caustic in different degrees,the pre-caustic washing performance of DGA is the best,followed by DEA.This is because both DGA and DEA are primary amines with same alkalinity.Whereas,MDEA is tertiary amine with week alkalinity and has the same removal performance of DEA at a higher concentration.