摘要
针对某油田区块井筒底部结蜡严重的问题,以原油和沉积物为研究对象,采用流变性测试、族组分分析、红外光谱分析、溶蜡点测试、动力学模型预测等手段,研究了该区块油井的蜡沉积规律与机理。结果表明,该区块油井原油中高碳分子、重质组分含量较高;井筒沉积物以长链直链烷烃为主,异构烷烃较少;原油中机械杂质含量较高,为蜡晶分子的析出提供了稳定的附着点;区块内的油套管钢表面为强亲油性,蜡晶分子容易在管壁沉积;越靠近井底,原油中大于临界碳数的蜡分子比例越大;蜡沉积速率随含水率的增加而减小,随流速的增加先增大后减小。
In order to solve the serious problem of wax deposition at the bottom of oil wellbore in an oilfield block,the wax deposition law and mechanism in wellbores were studied by means of rheological test,fractions analysis,infrared spectrum analysis,wax dissolution temperature test and kinetic model prediction.The results show that the content of high-carbon molecules and heavy-weight components in crude oil of the wellbores in this block is high,the sediment in the wellbores is dominated by long-chain straight-chain alkanes with less isoalkanes,and the content of mechanical impurities in the crude oil is high,which provides stable attachment points for the precipitation of waxy molecules;The steel surface of oil casing in the block is strong oil-friendly,wax crystal molecules are easy to deposit in the casing wall;the closer to the bottom of the well is,the larger the proportion of wax molecules greater than the critical carbon number in crude oil is;the wax deposition rate decreases with the increase of water content,and increases first then decreases with the increase of flow velosity.
作者
雷强
王巍
董金岗
田东海
杨晓东
梁昌晶
LEI Qiang;WANG Wei;DONG Jingang;TIAN Donghai;YANG Xiaodong;LIANG Changjing(Cooperative Development Project Department of Huabei Oilfield Company,Renqiu 062552,China;CNPC Engineering Technology Research Company Limited,Tianjin 300451,China;No.3 Oil Production Plant of Huabei Oilfield Company,Hejian 062450,China;Erlian Filiale of Huabei Oilfield Company,Xilinhot 026000,China)
出处
《石油工程建设》
2021年第2期15-19,共5页
Petroleum Engineering Construction
关键词
油井井筒
蜡沉积规律
结蜡机理
分子扩散
oil wellbore
wax deposition law
wax formation mechanism
molecular diffusion
