表面技术2016，Vol.45Issue(5)：84-90,7.DOI:10.16490/j.cnki.issn.1001-3660.2016.05.013
L80油管钢在CO2/H2S环境中的腐蚀行为
Corrosion Behavior of L80 Tubing Steel in CO2/H2S Environment
摘要
Abstract
ABSTRACT:Objective To study the corrosion behavior of L80 tubing in CO2/H2S environment.Methods Scanning elec- tron microscopy (SEM) and EDAX energy spectrum were used to analyze appearance characteristics and chemical compositions of corrosion products, and simulation experiment was conducted using HTHP autoclave and actual water sample after oil/water separation as the corrosive medium, to study the influence law of water cut, CO2/H2S partial pressure and temperature on L80 tubing corrosion rate.Results In CO2/H2S environment, L80 tubing inwall had obvious local corrosion characteristics, the depth of pitting corrosion in part area was more than 100µm,and corrosion products such as FeS,FeCO3 were formed. With the in-crease of water cut, the corrosion rate of L80 tubing gradually increased, the corrosion rate was 0.0377 mm/a when water cut was 30%, the corrosion rate was 0.0952 mm/a when water cut was 100%. When the CO2 partial pressure was constant, with the increase of H2S partial pressure, L80 steel corrosion rate increased; the corrosion rate was 0.0377 mm/a when H2S partial pres-sure was 0.04 MPa; the corrosion rate was 0.0952 mm/a when H2S partial pressure was 0.3 MPa. When the H2S partial pressure was constant, with increasing CO2 partial pressure, the corrosion rate of L80 steel did not significantly change, and the corrosion rate was smaller. With increasing temperature, the corrosion rate firstly significantly increased, and then decreased with a small-er amplitude. The corrosion rate changed from 0.0083 mm/a to 0.1264 mm/a when the temperature increased from 40℃ to 100℃, and the corrosion rate was the largest at about 100℃. The corrosion rate was 0.106 mm/a when the temperature was 120℃.ConclusionL80 tubing had mainly uniform and local corrosion in CO2/H2S environment. The corrosion rate of L80 tubing was more sensitive to H2S partial pressure than CO2 partial pressure. Good FeCO3 protective film was formed when CO2 partial pressure increased, reducing the corrosion rate. When the temperature increased to a certain range, the solubility of car-bonate and other slightly soluble salts was reduced, forming a protective layer on steel surface to decrease the corrosion rate.关键词
L80油管钢/CO2/H2S腐蚀/腐蚀产物/腐蚀速率/腐蚀形貌/影响因素Key words
L80 tubing steel/CO2/H2S corrosion/corrosion product/corrosion rate/corrosion morphology/influencing factors分类
矿业与冶金引用本文复制引用
林海,许杰,幸雪松,范白涛,杨进,王晓鹏..L80油管钢在CO2/H2S环境中的腐蚀行为[J].表面技术,2016,45(5):84-90,7.基金项目
总公司科技重大专项（YXKY-2013-TJ-01）；总公司科技重大专项（YXKY-2015-TJ-04）FundSupported by Science Fund for CNOOC Science and Technology Major Projects （）
