连续重整装置石脑油系统优化改造

Optimization of Naphtha System in Continuous Catalytic Reforming Unit

洛阳石化70×104t/a连续重整装置石脑油系统经过2011年优化后,仍存在问题,如预分馏塔分离精度差及塔底再沸炉超负荷运行、多功能塔(C202)分离效果不好、化工轻油产量多等问题。对此,在最大限度利旧情况下,对石脑油系统进行改动和优化,包括改变石脑油系统各塔作用,更换预分馏塔塔盘,调整预分馏塔操作参数,整体更换多功能塔,增上几台换热器等。优化改造后,T3302塔作为石脑油稳定塔,为预处理单元输送C_5及以上组分,减轻了预处理塔再沸炉负荷;多功能塔C202作为戊烷分离塔,生产高辛烷值的异戊烷油。通过优化,消除了现有石脑油加工工艺的不足,解决了油品平衡问题,同时提高了预分馏塔分离精度,改善预处理系统热负荷,降低装置能耗,解决了化工轻油积压憋库现象,并为重整反应提供了更优质原料。优化后,重整装置的总液收达到84.84%,产氢量为478.6m^3/t(相对重整进料量),月收益合计达到1332万元。

There were still some problems in the naphtha system of the 700kt/a continuous catalytic reform- ing unit at SINOPEC Luoyang Company after its optimization in 2011 such as the poor separation accuracy of prefractionator and multi-function tower, the overload operation of bottom reboiler in prefractionator and the high production of light naphtha.While making the best use of the existing equipment,a series of measures were taken to optimize the operation of the naphtha system ,including changing the function of each column in the naphtha system ,replacing the trays in the prefractionator,adjusting the operation parameters of the pre- fractionator,replacing the multi-function tower as a whole and adding a few heat exchangers.Mter optimiza- tion,tower T3302 functions as naphtha stabilizer and sends C5 and heavier hydrocarbons to the pretreatment unit,thus reducing the load of the reboiler in the prefractionater.The multi-function tower separates pentane from iso-pentane and produces high-octane iso-pentane.Through optimization,the disadvantages of the existing naphtha processing technology are overcome,the oil imbalance problem is solved,the separation accuracy of the prefractionator is increased ,the heat load of the pretreatment system is improved,the energy consumption of the unit is reduced ,the overstocking problem of light naphtha is solved, and feedstock with higher quality is provided for the reforming reactor.The total liquid recovery of the unit reaches 84.84%,the hydrogen pro- duction is 478.6m3/t （relative to feed rate）,and the total monthly profit reaches 13.32miUion yuan.