开工喷汽油技术在3.0 Mt/a催化裂化装置的应用

APPLICATION OF GASOLINE INJECTION TECHNOLOGY DURING START-UP OF 3.0 Mt a CATALYTIC CRACKING UNIT

中国石油兰州石化分公司3.0 Mt a重油催化裂化装置于2019年进行MIP技术改造后,在装置首次开工过程中,针对传统进料方式存在的气压机入口油气排放火炬、稳定塔回流罐大量排放不凝气、喷油前蒸汽需求量大、沉降器封闭罩外升温困难等问题,尝试使用了提升管喷汽油技术。通过计算得出最少需要喷汽油30 t h才能满足气压机富气量需求,选择在MGD(催化裂化增产液化气和柴油)喷嘴处温度达到530℃以上时开始喷汽油,3 h后再喷原料油。在实践中发现,采用开工喷汽油技术能够有效降低蒸汽用量,加速沉降器封闭罩外升温,提高催化剂循环量,同时在控制火炬排放与产品系统操作优化方面也取得了良好的效果,为同类MIP装置的开工提供了操作经验。

After the application of MIP technology in the 3.0 Mt a heavy oil catalytic cracking unit in Lanzhou Petrochemical Company of PetroChina in 2019,during the first operation of the unit,in view of the problems existing in the traditional feeding method,such as the discharge of oil vapor from the inlet of the gas compressor,the discharge of non-condensable gas from the reflux tank of the stabilizing tower,the large demand for steam before fuel injection,and the difficulty in raising the temperature outside the closed cover of the settler,an attempt was made to use the riser gasoline injection technique.It was calculated that at least 30 t h of gasoline was needed to meet the rich gas demand of gas compressor.Gasoline was injected when the temperature at the nozzle of MGD(FCC for maximizing gas and diesel)reached above 530℃,and then the feedstock was injected 3 hours later.It was found in practice that the gasoline injection could effectively reduce the steam consumption,accelerate the temperature rise outside the enclosure of the disengager,and increase the circulation of the catalyst,etc.At the same time,good results had been obtained in controlling torch discharge and optimizing operation of product system,which could provide operating experience for similar MIP unit.