摘要
国内某石化企业POSM装置是西班牙REPSOL首次在国内转让、投产的共氧化法环氧丙烷联产苯乙烯专利技术,以苯、乙烯、丙烯为原料,生产2×10^(5)t/a环氧丙烷及4.5×10^(5)t/a苯乙烯,该装置的脱水反应器出料泵位于“MBA脱水”单元,该泵的运行关系到整个单元的运行,该泵介质温度高、黏度随温度变化呈数量级急剧变化、自燃温度低、腐蚀性强,原配机械密封冲洗方案为PLAN 21+72+75,结构为无压串联式波纹管干气密封,不适用于该工况,改造后机械密封冲洗方案为PLAN 32+53A,结构为有压双端面波纹管机械密封,保障了装置的顺利开车。主要分析原配机械密封方案不合理的原因及改造机械密封方案的关键点,并为以后国内其他用户该工艺路线POSM装置类似泵的机械密封冲洗方案选择及选型选材提供参考。
The POSM plant of a domestic petrochemical company is established with adoption of the patented technology of cooxidation propylene oxide co-production styrene,which is the first time transferred from Spain REPSOL and put into production.This plant uses benzene,ethylene and propylene as raw materials to produce 200,000 tons/year propylene oxide and 450,000 tons/year styrene.The discharge pump of dehydration reactor in the plant is located in the"MBA dehydration"unit,and the operation of this pump has significant role to the operation of entire unit.The temperature of pumped fluid is very high,and the viscosity of the fluid changes sharply with the temperature change.Also,pumped fluid is with low spontaneous combustion temperature and strong corrosiveness.The original mechanical seal flush scheme was selected as PLAN 21+72+75 and unpressurized tandem metal bellows dry gas seal type was selected as the seal structure,which is not suitable for this working condition.After retrofit,the flush plan was changed to PLAN 32+53A with pressurized double metal bellows mechanical seal,which finally made the plant smooth start-up.This article mainly analyzed the inappropriate reasons for the original mechanical seal and key points of retrofit solution.What presented herein may be a reference for the selection of mechanical seal flush plan and material in other domestic POSM plant.
作者
贾邵秀
李舒君
王勇
刘大东
Jia Shaoxiu;Li Shujun;Wang Yong;Liu Dadong(Sinoseal Holding Co.,Ltd,Chengdu 610045,China;Sinochem Quanzhou Petrochemical Co.,Ltd.Quanzhou 362804,China)
出处
《化工设备与管道》
CAS
北大核心
2021年第6期51-55,共5页
Process Equipment & Piping
基金
国家重点研发计划“大科学装置前沿研究”重点专项,制造基础技术与关键部件,多相介质高参数机械密封件关键技术(2020YFB2010001)。
关键词
POSM装置
脱水反应器出料泵
机械密封
改造
POSM plant
discharge pump in dehydration reactor
mechanical seal
retrofit
