改善微剂油比的预提升技术及其应用效果

A Pre-lifting Process for Improving Micro Ratio of Catalyst to Oil and its Application Effects

通过计算分析,认为催化裂化油气管线结焦的原因为未气化油的存在。在催化裂化系统中,未气化油肉眼无法观察到,但对装置运行有多方面的影响,而微剂油比是影响未气化油生成的重要因素。根据未气化油产生的原因,开发得到有效改善微剂油比的预提升技术。采用预提升器的中国石油天然气股份有限公司大连石化分公司(以下简称大连石化)800 kt/a年重油催化裂化装置,干气产率由改造前的3.5%降低至2.6%,集气室和油气管线结焦基本解决;大连石化3.5 Mt/a重油催化裂化装置因烟机结垢振动而进行的清垢周期大幅延长,运行3年后停工检查发现,烟机结垢不明显,较改造前有明显改善。

Based on calculation and analysis,it is concluded that the cause of coking in FCC transfer line is non-gasified oil.In the FCC system,though non-gasified oil is invisible,it has many effects on the operation of the unit.The micro ratio of catalyst and oil is an important factor affecting the generation of non-gasified oil.A pre-lifting process was developed to effectively improve the micro ratio of catalyst to oil based on the cause of formation of non-gasified oil.With this process,the dry gas yield of the 800 kt/a RFCC unit of PetroChina Dalian Company is reduced from 3.5%to 2.6%,and the coking in disengager and oil transfer line is basically solved.For the 3500 kt/a RFCC unit of the Company,the cleaning cycle of expander due to the scaling vibration was greatly prolonged.The scaling of the expander was found to be significantly improved during the shutdown maintenance after three years operation with the pre-lifting process.