炼油厂气体分馏装置硫化合物分布初探

Study on sulfur distribution in gas fractionation unit

介绍脱硫后的催化裂化LPG中硫化物的形态及其沸点,采用PROⅡ模拟软件并选择了适宜的状态方程,对LPG经过气体分馏装置分离后各产品中硫化物的分布进行了计算,并对原料总硫、硫化物含量及LPG组成等变化因素对产品硫分布的影响进行了分析。指出LPG中的硫化物在分离过程中基本按挥发度的大小分布于各产品中,精丙烯产品中的硫化物主要是羰基硫;丙烷馏分中的硫化物主要是甲硫醇;乙烷气中主要是羰基硫;C4,C5馏分中的硫化物主要是甲硫醇、乙硫醇、二硫化物和甲硫醚。气体分馏装置各产品中的硫含量大小,主要取决于LPG中的硫形态分布。

The forms and boiling point of sulfur compounds in FCC LPG after desulfurization are de- scribed. The sulfur compound distributions in the products separated in LPG fractionation unit are calculated by using PRO II simulation software and appropriate state equation. The impacts of total sulfur, sulfide con- tent and LPG compositions in feedstock on sulfur distribution in products are analyzed. It is found that the sul- fides in LPG are distributed in the products based upon the volatilities. The sulfide in purified propylene is mainly hydroxide sulfur, the sulfide in propane fraction is mainly methyl mercaptan, the sulfide in ethane is mainly hydroxide sulfur and sulfides in Ca and C4 fractions are mainly methyl mercaptan, ethyl mercaptan, bid-sulfide and dimethyl sulfide. The contents of sulfides in the fractionator products are determined by the sulfur distribution in LPG.