DCC-plus装置分馏顶循系统的节能优化改造  

Energy saving optimization transformation of fractionation top circulation system in DCC-plus unit

作　　者：钟海博 李贵 ZHONG Hai-bo;LI Gui(Ningbo Daxie Petrochemical Co Ltd,CNOOC,Ningbo 315812,China)

机构地区：[1]中海石油宁波大榭石化有限公司,浙江宁波315812

出　　处：《石化技术与应用》2023年第6期471-475,共5页Petrochemical Technology & Application

摘　　要：针对中海石油大榭石化有限公司220万t/a催化裂解(DCC-plus)装置分馏塔分馏顶循系统换热能力不足,即使冷回流泵满负荷全运行,仍出现分馏塔塔顶热负荷过高,塔顶压降过大,甚至粗汽油干点经常超标等问题,对该DCC-plus装置与气分装置进行了热联合改造。结果表明:经改造及运行优化后,该装置分馏塔基本达到最佳运行状态,不仅粗汽油干点达标且明显降低,且运行平稳受控于177~185℃;而且分馏塔分馏顶循环返塔温度被控制在105.2℃,有效减缓了顶循换热器HCl-H2S-H2O腐蚀环境及露点腐蚀;分馏塔塔顶冷回流量比改造前降低了36.7%,塔顶空冷器及冷回流泵运行台数较改造前分别减少了6,1台,有效避免了之前在高温夏季不得不满负荷运行时的系统安全隐患;而且该项热联合技术改造还使气分装置的低温热水总用量较改造前降低了84.8 t/h。In response to the insufficient heat exchange capacity of the fractionation top circulation system of the fractionation column in the 2.2 Mt/a catalytic cracking(DCC-plus)unit of Daxie Petrochemical Co Ltd,CNOOC,even if the cold reflux pump ran at full load,there were still problems such as the high thermal load on the top of the fractionation column,the excessive pressure drop at the top of the fractionation column,and even frequent exceeding of the dry point of crude gasoline.So the thermal joint utilization technical transformation was carried out on the DCC-plus unit and the gas separation unit.The results showed that after the transformation and operation optimization,the fractionation column basically reached the optimal operating state.Not only did the dry point of crude gasoline meet the standard,but also significantly decreased,and its operation was stable and controlled at 177-185℃.Moreover,the top circulation return temperature of the fractionation column was controlled at 105.2℃,which effectively slowed down the corrosion environment of HCl-H2S-H2O and dew point corrosion of the top circulation heat exchanger.Comparing with that before the technical transformation,the cold return flow rate at the top of the fractionation column decreased by 36.7%,and the number of overhead air coolers and cold reflux pumps in operation decreased by 6 and 1 units,respectively,which effectively avoided the potential system safety hazards when they ever all had to be running at full load in each high temperature summer season before.Moreover,the total consumption of low-temperature hot water in the gas separation unit reduced by 84.8 t/h.

关 键 词：催化裂解(DCC-plus)装置 顶循环 低温热 粗汽油干点 腐蚀 热联合利用 节能改造 

分 类 号：TE683[石油与天然气工程—油气加工工程] TQ624.41[化学工程—精细化工]