常压塔顶的腐蚀分析与防护措施

针对中国石油兰州石化公司500万t/a常减压装置的常压塔塔顶存在的腐蚀问题,采取更换空气冷却器材质,增加缓蚀剂注入点,优化注水量、注缓蚀剂量及其含量等措施,对装置进行了改进。结果表明,改进后装置的最佳工艺条件为:缓蚀剂含量26×10-6,注缓蚀剂量0.6 t/h,注水量2 t/h。与改进前相比,改进后第5~第8台空气冷却器出口含硫污水Fe2+质量浓度有了大幅度降低,塔顶含硫污水Fe2+质量浓度合格率达到100%。

Corrosion analysis and protection measures of the top of an atmospheric tower

According to corrosion problems at the top of atmospheric tower in a 5 Mt/a crude oil distillation unit of Lanzhou Petrochemical Company, PetroChina,the material of air cooler was replaced, the corrosion inhibitor injection points were added, and the water injection rate, corrosion inhibitor injection rate and its content were optimized. The results showed that after the above - mentioned improvement, the optimum process conditions were the mass fraction of inhibitor 26 × 10^-6 , corrosion inhibitor in- jection rate 0.6 t/h, water injection rate 2 t/h. Fe^2＋ mass concentration in sulfur- containing wastewater at the outlets of air coolers 5 -8 decreased siginifi- cantly,the pass rate of Fe^2＋ mass concentration in sulfur - containing wastewater reached 100% at tower top compared to those before the improvement.