常压蒸馏装置的腐蚀与防护

针对炼制长庆轻质低硫含酸原油常压蒸馏装置腐蚀情况,对常压塔、初馏塔塔内件、塔壁以及常顶挥发线等多次进行腐蚀检查,未发现明显腐蚀情况。出现腐蚀的部位主要发生在：常顶换热器和空冷器;加热炉转油线弯头局部减薄穿孔泄漏;转油线进塔处弯头减薄,其他高温管线及加热炉炉管运行情况良好,没有发现减薄情况。就已经出现的几个主要腐蚀部位,从原油性质、关键设备选材及工艺防腐和腐蚀检测等方面进行腐蚀原因分析,提出合理选材、加强工艺防腐优、化防腐药剂以及完善在线腐蚀监测与管理系统措施,解决有关设备的腐蚀问题,为常压装置长周期安全平稳运行提供保证。

Corrosion in Atmospheric Distillation Unit and Protection

To solve the corrosion problems of atmospheric distillation unit processing Changqing light low-sulfur acidic crude oil,multiple corrosion inspections have been performed in atmospheric tower,tower walls and atmospheric tower overhead vapor line,and no obvious corrosions have been found.The corrosion thinning and corrosion leaking mainly occurred in atmospheric tower overhead heat exchanger,air coolers,elbow in furnace oil transfer line and elbow in oil transfer line to the inlet of tower.Other high-temperature pipelines are operating satisfactorily and no corrosion thinning has been found.Based upon the corrosions found in several locations of the atmospheric distillation unit,the corrosion causes are analyzed in respect of crude oil properties,material section of critical equipment,process corrosion prevention and corrosion detection,and effective corrosion protection measures have been proposed such as selection of appropriate materials,strengthening process corrosion prevention,optimization of corrosion inhibitors and improvement of on-line corrosion detection and management system,etc to provide good conditions for the long-term safe reliable operation of the atmospheric distillation unit.