含硫油田采出水系统腐蚀机理及防腐技术研究

Research on Corrosion Mechanism and Anticorrosion Technology of Produced Water System in Sulfur Oilfield

对含硫区域采出水系统开展腐蚀机理研究,首先对含硫区域站点采出水系统进行水质分析并对腐蚀产物进行分析,发现采出水系统腐蚀主要受到水中较高的矿化度、CO_(2)浓度、H_(2)S浓度、Cl^(-)含量及水型等因素决定的。其中,对腐蚀影响较小的是氯化钠型水系中硫化物,这是由于偏碱性条件下生成致密的Fe_(x)S_(y),抑制了钢材与腐蚀介质的接触;当水体系中存在CO_(3)^(2-)、HCO_(3)^(-)和Ca^(2+)后,腐蚀速率增加;基体铁与腐蚀产物膜的界面处,在Cl-的催化作用下,导致界面区域阳极溶解加速形成蚀坑。最后,对在用除硫剂和缓蚀剂等进行室内评价,发现除硫剂TL-10具有优异的除硫效率和较高的吸附容量;缓蚀剂MH-46具有良好的缓蚀效率。

This paper studies the corrosion mechanism of the produced water system in the sulfur-containing area.First,the water quality of the produced water system in the sulfur-containing area site is analyzed and the corrosion products are analyzed.It is found that the corrosion of the produced water system is mainly affected by the high salinity,CO_(2) concentration,H_(2)S concentration,Cl^(-) ion content,water type,and so on.Among them,the sulfide in the sodium chloride type water system has less effects on corrosion due to the formation of dense Fe_(x)S_(y) under alkaline conditions,which inhibits the contact between the steel and the corrosive medium.When there are CO_(3)^(2-) and HCO_(3)^(-) and Ca^(2+) ions in the water system,the corrosion rate increases.Under the catalysis of Cl-ions,the anodic dissolution in the interface area between the matrix iron and the corrosion product film is accelerated to form corrosion pits.Finally,the indoor evaluation of the in-use sulfur remover and corrosion inhibitor is investigated.The sulfur remover TL-10 has excellent sulfur removal efficiency and high adsorption capacity and the corrosion inhibitor MH-46 has good corrosion inhibition efficiency.