国内成品油储罐和长输管线腐蚀现状与防护

Corrosion and corrosion protection of product oil tanks and long-distance pipelines

介绍了国内钢质成品油储罐和长输管线腐蚀情况,通过分析得知钢质成品油储罐外腐蚀的主要原因是大气环境腐蚀;而储存油品中所含的无机盐、酸、硫化物、水和氧等腐蚀介质则是引起储罐内腐蚀的主要原因。管线外腐蚀主要有:(1)土壤中水和空气引起的钢表面氧腐蚀;(2)管道铺设过程中的大气腐蚀;(3)土壤中电解质引起的电化学腐蚀;(4)微生物腐蚀,包括氧化菌和厌氧菌(硫酸还原菌等)繁衍腐蚀;(5)杂散电流腐蚀。管线内腐蚀的主要原因是由于H2O,O2,CaCO3,SiO2和铁锈等杂质的存在,使极弱的成品油化学腐蚀转变为电化学性质的腐蚀所致。根据实际工程情况,制定了合适的防腐蚀方案。

The present status of corrosion and corrosion protection of domestic steel oil tanks and pipelines is introduced. The analysis of the corrosion has concluded that the external corrosion of steel oil tanks is mainly atmosphere corrosion, and the internal corrosion is mainly the corrosion caused by corrosion media like inorganic salts, acid, sulfides, water and oxygen etc in product oil. The external corrosions are （ 1 ） the oxygen corrosion on steel surface by water in soil and air, （2） atmosphere corrosion in laying operation of pipelines, （3） electro - chemical corrosion by electrolyte in soil, （4） microorganism corrosion, including reproduction corrosion of oxygenation bacteria and anaerobic bacteria （sulfur reduction bacteria） and （5） stray current corrosion. The internal corrosion of pipelines is mainly the electro - chemical corrosion caused by H20, 02, CaCO3, SiO2 and steel rust, etc. A practical corrosion protection scheme has been developed based upon these conditions, which provides a good reference for the corrosion protection of product oil tanks and long - distance pipelines.