硫磺回收塔底重沸器腐蚀原因分析

Analysis of Corrosion Causes of Bottom Reboiler of Sulfur Recovery Tower

中国石油天然气股份有限公司大连分公司某装置硫磺回收再生塔底重沸器使用不久便发生腐蚀泄漏。分析认为RNH2 CO2 H2 S H2 O介质腐蚀、因胺液降解生成热稳定性物质 (HSAS)的腐蚀、冲刷作用以及重沸器结构不合理是产生腐蚀的主要原因 ,E10 2壳层焊缝属应力腐蚀开裂。采取防止氧进入系统、保持胺液清洁、对重沸器进行改造、增加消除应力退火以及更换重沸器管板材质为Cr5Mo或 12CrMo钢等措施 ,可以延长设备的使用寿命。

Corrosion leakage occurred in the bottom reboiler of a sulfur recovery tower in Dalian Petrochemical Company/Petrochina Co.,Ltd not long after it was put into operation. The analysis concludes that RNH 2-CO 2-H 2S-H 2O corrosion, the impingement and corrosion of HSAS and inappropriate construction design of the reboiler are the main causes of the corrosion and corrosion cracking of welds of E102 shell. The service life of the reboiler can be extended by preventing oxygen from entering the system, keeping the liquid amine clean, redesigning the reboiler, stress relieving by anneal and replacing the material of the tube sheet of the boiler with Cr5Mo or 12CrMo, etc.