催化裂化装置未汽化油的模拟计算和解决措施

Simulation calculation and solution of unvaporized oil in catalytic cracking unit

以Aspen HYSYS模拟软件为基础,分别对催化裂化装置的原料和油浆刚进入提升管时的汽化状态,提升管出口混合物料的汽化状态进行了模拟计算,证明了在提升管汽化段有少量原料和部分回炼的油浆未完全汽化,未汽化油增加了提升管、沉降器、分馏塔的结焦倾向,导致装置非计划停工。文中对某炼化公司催化裂化装置沉降器旋风分离器设计改造后出现的结焦部位后移等问题进行分析,指出通过采用MIP工艺、优化原料雾化效果、提高反应温度、增加剂油比、减少回炼量等措施可有效抑制未汽化油冷凝结焦对装置长周期运行的影响。

Based on the simulation software Aspen HYSYS,the vaporization state of the raw material and the slurry entering the riserand the vaporization state of the mixed material at the riser outletin the FCC unit are conducted simulation calculation respectively,which is proved that a small amount of raw material and part of the refined slurry are not completely vaporized in the riser section increasing the the coking tendency of riser,settler and fractionator,resulting in unplanned plantshutdown.This paper analyzed the problems on coking parts shifting backward after the design transformation ofsettler cyclone separator,and pointed out that it could effectively inhibit unvaporized oil condensation and coking from affectingthe long-lead operation of the plant by using MIP technology,optimizing atomization effect of raw materials,improving reaction temperature and agent oil ratio,reducing the quantity of recycle and other measures.