摘要
稠油井特别是深层稠油井因油黏稠而难以举升,而泡沫油井往往产量较高,因此立管稠油-泡沫流阻力特性研究将有助于稠油井生产新工艺的开发。采用立管环道装置及其泡沫环生成系统,实验研究立管稠油在水基泡沫作用下的阻力特性,分析泡沫流量对稠油流动摩阻的影响及减阻机理,探索稠油井减阻的新途径,建立稠油-泡沫中心流的压降预测模型。研究结果表明,稠油井注入适量的泡沫可形成稳定的稠油-泡沫环中心流,从而有效降低稠油井筒举升阻力;当泡沫/油流量比高于临界值0.1时,减阻率一般在60%以上;当油壁间形成完整的泡沫隔离润滑层时,其压降预测值与实测值的相对误差一般在±20%以内,满足工程设计要求,且为立管稠油-泡沫中心流压降预测提供了较可靠的方法。
The heavy oil is difficult to be lifted out of the wells,especially the ultra-deep wells,for its high viscosity,while the foamy oil wells often exhibit high production rates.Study on drag characteristics of heavy oil- foam flow in vertical pipe will contribute to the development of new processes for production in heavy oil wells. A vertical flow loop installation with a foam annulus generating system was used to investigate the drag properties of heavy oil with aqueous foam flowing through a vertical pipe section. The effects of foam flow rates on heavy oil flow friction and the friction reduction mechanism were analyzed to explore a new method for heavy oil flow friction reduction in wellbore. A model for predicting pressure drop of heavy-oil-foam core flow was established. The study results indicated that injecting proper amount of foam could form a stable core flow of heavy-oil and foam rings in the heavy oil well,which could effectively reduce its shaft lifting resistance,and the drag reduction efficiency generally exceeded 60% while the flow ratio of foam to oil was above the critical value of 0.1. And when a complete isolation-lubrication film of foam was formed between the oil and the wellbore,the relative errors of predicted and measured pressure drops were within ±20% basically,able to meet the engineering design requirements,and this would provide a reliable method to predict the pressure drop of the core flow of heavy oil-foam.
出处
《钻采工艺》
CAS
北大核心
2016年第5期52-55,103,共4页
Drilling & Production Technology
基金
国家自然科学基金"稠油流动边界层在水基泡沫作用下的阻力特性研究"(51074136)
高等学校博士点基金项目"稠油掺水流动黏度测定及压降预测研究"(20115121110004)资助
关键词
稠油-泡沫流
立管
阻力特性
泡沫减阻
压降预测
heavy-oil-foam flow
vertical pipe
drag characteristic
friction reduction using foam
pressure drop prediction
