优化焦化分馏塔操作提高轻油收率

Coking Fractionator Optimization to Boost Light Oil Yield

采用过程模拟技术建立了常减压蒸馏与延迟焦化联合装置的流程模型,重点分析了分馏塔顶循流量、柴油内回流流量、中段回流量、蜡油返26层塔板流量、进料温度与蒸发段温度等操作要素对提高装置轻油收率的影响。经过模型计算,通过优化中段回流和蜡油上返塔的流量来降低蜡油、柴油的馏程重叠度,提高柴油深拔的程度,对提高装置轻油收率效果最为明显。参照模型优化操作参数,对装置进行了调整,实践证明蜡油D1160 10%馏程温度由优化前348.6℃提高到357.6℃,柴油D86 95%馏程温度由优化前350～360℃提高到361.3℃,可至少提高装置轻油收率0.34百分点。

The process simulation model combing crude distillation unit and delayed coking unit is established with process simulation technology,in order to analyze the influence of some operating elements on light oil yield,mainly including the coking fractionator overhead circulating flow,the diesel internal reflux,the mid-section reflux,the gas oil reflux to the 26th plate,the feed temperature and the evaporator temperature.The model calculation indicates that,light oil yield can be maximized by optimizing the mid-section reflux and the gas oil upper-reflux to reduce the distillation range overlap of gas oil and diesel oil,and to improve diesel deep-cut level.According to the model calculation results,the coking fractionator is adjusted with optimal operating parameters,and actual operation proves that light oil yield can be improved by at least 0.34%when the 10%distillation temperature of gas oil D1160 is raised from 348.6℃to 357.6℃,and the 95%distillation temperature of diesel oil D86 is lifted from 350-360℃to 361.3℃.