硝酸装置低压反应水冷器的腐蚀及改进措施  

Causes of Corrosion in Low-pressure Reaction Water Cooler in Nitric Acid Plant and Improvement

作　　者：黎志敏[1] 

机构地区：[1]杭州龙山化工有限公司,浙江杭州311228

出　　处：《石油化工腐蚀与防护》2014年第6期22-24,共3页Corrosion & Protection In Petrochemical Industry

摘　　要：介绍了双加压法硝酸装置中的主要设备低压反应水冷器的工况及其特性,分析了该设备由于温差应力腐蚀、高温冷凝稀酸冲刷和Cl-聚集发生应力腐蚀等各种腐蚀破坏,最终导致产生换热管和管板的腐蚀泄漏现象。同时还存在检修维护成本过高的问题。针对行业内普遍存在的问题,提出了保证冷却水质量、优化设备结构、采用内孔焊等先进制造工艺和改变设备布置形式等一系列优化改进措施,有效地解决了目前低压反应水冷器存在的腐蚀问题,延长使用寿命。通过改造能大幅度提高生产装置的生产效率,保证了产品的质量和产量,预计设备使用寿命能从以前的2 a提高到4 a以上,同时降低了设备检修维护成本,是值得行业内推广应用的优化改造措施。The operating conditions of low - pressure reaction water cooler and its characteristics in dual pressure nitric acid plant are introduced. The corrosion damages which lead to the corrosion leaking of heat exchanger tube and plate are analyzed such as temperature difference stress corrosion of equipment, high - temperature condensate acid impingement erosion and stress corrosion from C1- accumulation. The high maintenance costs are also studied. To solve these problems, improvement and optimization measures have been proposed such as control of cooling water quality, optimization of equipment construction and application of internal hole welding, etc, which have effectively controlled the corrosion of low - pressure reaction water cooler and extended the service life. The revamping of the unit has greatly improved the unit operation efficiency and ensured the product quality and production. The service life of equipment is expected to be extended to over 4 years from 2 years. The costs of maintenance of equipment are reduced. It is an optimal improvement measure for the application in the industry.

关 键 词：双加压法硝酸 低压反应水冷器 腐蚀 优化改造 

分 类 号：TQ051.5[化学工程]