常减压蒸馏装置防腐蚀措施及效果分析

管输油劣质化导致常减压蒸馏装置电脱盐合格率低,使低温防腐蚀和高温防腐蚀均存在薄弱环节.Ⅱ套常减压蒸馏装置通过电脱盐脉冲技术改造,脱盐合格率由88.60％提高到96.59％；增上初馏塔顶、常压塔顶和减压塔顶腐蚀在线监测系统后,低温位腐蚀得到了有效控制；加热炉余热回收系统增上双面双翅片铸造板式空气预热器,排烟温度由175℃...

Anti-corrosion measures of atmospheric-vacuum distillation unit and performance analysis

The low-quality crude oil of atmospheric-vacuum distillation unit in SINOPEC Wuhan Company has resulted in low on-specification rate of desalted oil of electro-static desalter and deterioration of low-temperature corrosion and high-temperature corrosion.After revamping of the desalter with pulse desalting process for No.Ⅱ atmospheric-vacuum distillation unit,the on-specification rate of desalted oil was increased to 96.59% from 88.6%.With installation of on-line corrosion monitoring system on atmospheric tower overhead,the low-temperature corrosion was effectively brought under control.The addition of plate air pre-heater with finned plates has reduced the flue gas emission temperature to 140 ℃ from 175 ℃,the heat efficiency has been increased from 90.2% to 91.5% and 1.6 MW of heat has been recovered.The injection of high-temperature corrosion inhibitor in the 2nd sidedraw of vacuum tower has effectively controlled the corrosion in high-temperature section of vacuum tower.In the deep-cut revamping of No.Ⅰ atmospheric-vacuum distillation unit,the materials in high-temperature section were upgraded and anti-corrosion adaptability of equipment and process has been improved for processing low-quality crudes from pipelines.