反应温度对FCC重汽油馏分两段加氢改质的影响

Impact of reaction temperature on two-stage hydro-upgrading of heavy FCC gasoline

通过FCC重汽油馏分加氢脱硫-辛烷值恢复两段工艺的温度条件实验,表明随反应温度升高,加氢脱硫单元中产物硫含量降低,烯烃含量降低,265 ℃后烯烃含量降幅增大,与原料相比降低29.4％；辛烷值恢复单元可使加氢脱硫产物的硫进一步得以脱除,在370 ～375℃,随温度升高,硫含量下降趋势明显,产物的烯烃含量较加氢脱硫产物进一步降低,随温度升高,烯烃含量小幅降低,365℃后,烯烃体积分数低于18％；对于硫质量分数770 μg/g的FCC汽油,在生产国Ⅳ标准汽油时,重汽油馏分加氢脱硫-辛烷值恢复两段工艺适宜的一反/二反温度为250～265℃/365℃.

The temperature condition test of two-stage heavy FCC gasoline fraction hydrodesulfurization and octane recovery process shows that the product sulfur and olefin are reduced with the rising reaction tem- perature in the hydrodesulfurization unit. When the temperature exceeds 265 ℃, the olefin drop increases, and is 29.40% lower as compared with the feedstock. In the octane recovery unit, sulfur is further removed. At the temperature of 370 - 375 ℃, sulfur declines significantly and the product of olefins is slightly reduced with rising temperature. When the temperature is above 365 ℃, olefin is lower than 18%. For the FCC gaso- line with 770 μg/g sulfur, the appropriate temperature of heavy gasoline fraction hydrodesulfurization-octane recovery process is 250 ～ 265 ℃/365℃ when Guo IV standard gasoline is produced.