雅克拉凝析气田腐蚀状况与分析  

Corrosion Situations and Analysis in a Condensate Gas Field Named Yakela

作　　者：左兴凯 

机构地区：[1]中国石油化工股份有限责任公司销售事业部,北京100029

出　　处：《石油钻探技术》2005年第4期60-62,共3页Petroleum Drilling Techniques

摘　　要：雅克拉凝析气田油管的腐蚀部位主要集中在油管的公扣端、丝扣部位和350-3500mm的油管内壁。油管内壁腐蚀形态呈密布的蚕豆、绿豆大小的蚀坑,腐蚀严重的部位呈纵向排列沟槽状坑蚀;油管外壁呈虫蛀状孔群。腐蚀产物以FeCO3为主,占70%,表明油管以CO2腐蚀为主。腐蚀的主要原因:天然气中CO2含量高,其分压远远超出CO2的临界分压(0.02MPa);生产井的井筒温度高,一般为65-135℃;地层水中Cl-质量浓度高达6.5×104mg/L;工作制度不合理,采气量过大,井内气液流速高并携带有固体颗粒。从曾用的防腐方法的效果看,采用13Cr钢油管防腐效果最好。建议针对性地对各种防腐方法进行综合评估,建立有现场腐蚀监测系统,为采取综合防腐措施提供技术数据。In the Yakela condensate gas field, corrosion parts of tubing mainly are pin ends, threads, and inside walls from 350m to 3500m. The inside wall corrosion shapes present dense pit like a horsebean and a mung bean. The severe corrosion parts present arranged slots. The outside wall presents worm pit groups. Seventy percent of corrosion product is FeCO3 , which show tubing corrosion is mainly caused by CO2. The main corrosion reasons are high CO2 contents in natural gas, fractional pressure being much higher than the critical one (0. 02MPa), high wellbore temperature of 65-135℃, high Cl contents up to 6. 5×104mg/L in formation water, illogical work system, too much gas producing, high gas flow speed and accompanied with solids in wellbore, etc. Effects of corrosion protection method used show that the 13Cr tubing is the best one. The paper suggest that all various corrosion protection methods should be evaluated separately, and field corrosion monitoring system should be established to provide technical data for developing comprehensive corrosion prevention measures.

关 键 词：凝析油气田 CO2腐蚀 防腐 雅克拉 

分 类 号：TE983[石油与天然气工程—石油机械设备]