催化裂化装置加工劣质原料油的操作优化

Operation optimization of a FCC unit processing low-quality feed

中国石化金陵石化公司蜡油加氢预处理装置焦化蜡油掺炼比例由20%提高至40%,常减压装置实施减压深拔操作,减压渣油500℃馏出率由6.0%降至5.2%,导致下游催化裂化装置混合原料密度高、重金属含量高和总氮含量高,提升管进料呈现重质化和劣质化倾向。针对Ⅰ催化裂化装置加工劣质原料油对生产的影响开展技术分析,加强催化裂化装置生产技术优化、采取改进焦化蜡油的加工流程、提高原料雾化效果、优化沉降器汽提蒸汽用量、减少回炼油的回炼量、改善催化剂性能以及提高钝化剂的加注量等措施,使催化裂化装置的技术、经济指标逐步恢复。优化后平衡催化剂微反活性由53.98%上升到56.00%,装置处理量提高了11 t/h,总液体收率增加1.90%,焦炭产率降低0.32%,干气产率降低0.70%。

In the gas oil hydrotreating unit in SINOPEC Jinling petrochemical Company, the percentage of coker gas oil in the blend feed was raised to 40% from 20%. When the deep-cut vacuum distillation was adopted for the atmospheric-vacuum distillation unit, the distillation rate of 500 ℃ VR fraction was reduced to 5.2% from 6.0% , leading to higher density, higher metal and higher total N2 in the feed of downstream units as well as deterioration of feed to riser reactor. Based upon the analysis of the impact of deterioration of FCCU feed quality on the unit operation, the adoption of measures such as improvement of delayed coker process, and optimization of FCCU operation such as improvement of atomization of feed, optimization of steam utilization rate of settler, utilization of recycle oil for recycle, improvement of catalyst performance and increasing passivator addition rate, etc has brought the economic index of the FCCU back to that of normal operation. The micro-activity of equilibrium catalysts was elevated to 56.00% from 53.98%. The unit capacity was increased by 11 t/hr. The total liquid yield rose by 1. 9% and ch7 gas make was lowered by 0.7%.