高密度聚乙烯淤浆环管工艺反应器黏壁原因及减缓措施

Cause analysis and solutions for wall sticking in reactor of HDPE slurry loop process

对高密度聚乙烯淤浆环管工艺反应器黏壁的原因进行了分析,并提出了相应的处理措施。反应器黏壁原因主要包括低聚物的产生,生成低密度及支化度大的产品,聚合温度过高,静电,设备性能差,转产时置换不彻底,反应器内的固相含量不合理等。通过减小催化剂浓度,合理控制共聚单体浓度,严格控制反应温度,采用Cr系催化剂生产,保证反应器的光洁度,抑制静电水平,转产时彻底置换出残留物,合理控制反应器内的固相含量等方式,可减缓反应器黏壁,延长装置运行周期。

The causes of wall sticking in the reactor of high density polypropylene（HDPE）slurry loop process are described and solutions are offered. The factors contributing to the accident include the formation of oligomer,the production of low density and high branching polymer,high polymerization temperature,static electricity,poor performance of equipment,incomplete replacement in production changing, and solid content in reactor. Wall sticking in reactors can be mitigated by switching to Cr-based catalysts,reducing the concentration of catalyst,adjusting the concentration of comonomer,strictly controlling the temperature in reactor,ensuring the smoothness in reactor,eliminating the static electricity,completely replacing the residue when production changing,and controlling the solid phase content in reactor. The operation period of the plant is therefore prolonged.