聚异丁烯装置后处理部分腐蚀与防护

某公司聚异丁烯装置2000年建成投产，主要工艺是以混合c。为原料，以AIC1，为催化剂生产聚异丁烯。其后处理部分自投产以来连续发生腐蚀泄漏现象，给安全生产造成很大隐患。通过对腐蚀情况调查，发现腐蚀主要发生在脱丁烷塔、再沸器、闪蒸罐、T-103塔及管线的死区、冷区处，主要是盐酸的酸性腐蚀、氯离子的点蚀、应力腐蚀及硫腐蚀。提出防腐措施：尽量减少物料中的水含量、增设pH值监测点及注氨点、由手工控制注氨改为自动控制、加强保温管理、为仪表建立循环线、对阀门等保温困难部位加设保温箱或拌热箱、控制系统中的硫含量等，保障了生产安全。

Corrosion of Post Processing Facilities of Poly-isobutylene Unit and Protection

The poly-isobutylene unit in Jinzhou Kaiyuan Petrochemical Company was started up in 2000. The unit was mainly operated with mixed C4s to produce poly - isobutylene with AIC13 catalyst. The corrosion leaking occurred in the post processing facilities after start up which imposed a great safety hazard to the safe operation of the unit. The detailed investigation and analysis of the corrosion have found that the corrosion mainly occurred in the debutanizer, reboiler, flash drum, T - 103 tower and cold zone and dead end of the pipelines. The main corrosion mechanisms are chlorhydric acid corrosion, chlorine ion pit corrosion, stress corrosion and sulfur corrosion. Based upon the analysis of these corrosions, practical effective countermeasures are proposed such as minimization of water in feedstocks, addition of pH value monitoring points and ammonia injection points, replacement of manual ammonia injection with automatic ammonia injection, strengthening of heat insulation, installation of circulation line for instrument, installation of heat insulation box or heat tracing box for the valves and control of sulfur in the system, etc to ensure the save operation of the unit.