溶剂抽提改质减压瓦斯油作蒸汽裂解原料

摘要

对溶剂抽提改质大庆减压瓦斯油(VGO)作蒸汽裂解原料的工艺进行了研究。结果表明， N-甲基吡咯烷酮(NMP)具有优异的脱芳烃和脱胶质性能，在200 t/a 中试抽提装置上，温度75 ℃、相比(原料油与溶剂体积比)为2的条件下，试验所得抽余油的收率和脱芳烃率均大于70%， BMCI 值小于16，经785 ℃模拟蒸汽裂解试验，抽提改质油的乙烯收率和乙烯、丙烯及丁二烯总收率分别大于27%和50%，表明 NMP 溶剂抽提改质减压瓦斯油的工艺是一条生产蒸汽裂解原料的可行途径。%Upgrading vacuum gas oil by solvent extraction was investigated. It was found that NMP(N-methyl-2-pyrrolidone) had excellent de-aromatics and de-resin performance for VGO. Extractions were conducted on a 200t/a pilot plant. Under the conditions of an extraction temperature of 70 ℃ and a VGO/NMP phase ratio of 2, the raffinate yield and de-aromatics rate were all higher than 70%, and the BMCI value of the raffinate was lower than 16. The pyrolysis results showed that the ethylene yield and the sum of ethylene, propylene and butadiene at a pyrolysis temperature of 785 ℃ were higher than 27% and 50% respectively. The extraction process with NMP as a solvent is a feasible route of upgrading VGO for pyrolysis feedstock.