催化脱硫系统的腐蚀与防护

自武汉石油化工厂催化脱硫装置投用以来,多次发生腐蚀破裂泄漏.10年内曾两次更换溶剂脱硫塔.文章讨论了MEA.MDEA等几种脱硫剂和溶剂中的CO_2、H_2S布对脱硫系统腐蚀的影响.经试验发现,脱硫剂在脱硫系统中起了很好的缓蚀作用.该系统的均匀腐蚀主要由CO_2引起,H_2S的存在减缓了CO_2对设备的均匀腐蚀.该系统的IGSCC不仅与脱硫剂类别有关, 还与溶剂中CO_2、H_2S含量有关,H_2S含量高时.不会发生IGSCC,少量H_2S的存在会导致脱硫剂CO_2-H_2S体系的IGSCC.最后提出了6条防护措施与建议.

Corrosion of Catalytic Desulfurization Unit and Protection

Leaking from corrosion cracking occurred many times in the catalytic desulfurization unit in Wuhan Petrochemical Plant since its commissioning. Solvent desulfurization tower had to be replaced two times within 10 years. Several desulfurization agents such as MEA and MDEA etc. and the impact of corrosion CO2 and H2S in solvents on the corrosion of desulfurization system were discussed. Th experiments showed that the agents worked well in corrosion inhibition in desulfurization system. The uniform corrosion of the equipment. The IGSCC was related not only to the type of desulfurization agents used but also to the contents of CO2 and H2S of the solvent. With higher H2S,there was no 1GSCC. The low H2S content would lead to IGSCC in CO2-H2S system. Six corrosion protection measures were finally suggested.