旋流式井下油水分离同井注采技术发展现状及展望

井下油水分离同井注采技术是实现高含水油田经济稳定开发的有效措施,经过几十年发展,形成了旋流分离、重力沉降等多种井下油水分离方式,发展出与之配套的离心泵、螺杆泵、有杆泵等动力系统和封隔系统。但同时也在技术稳定性、可靠性上存在诸多问题,使用范围受到介质参数、工艺特点、油藏数据等多方面的影响,技术推广应用受到限制。随着技术的不断进步,井下油水分离同井注采技术将向着高效、稳定、小型化、低成本、智能化方向发展：研制轴向导流入口水力旋流器,适应139.7 mm （5-1/2″）套管井的应用;开展三次曲线和內锥水力旋流器、多级串联水力旋流器等分离装置研究和应用,提高油水分离效果;开发模块化水力旋流器技术,降低制造成本;研究同井注采系统优化配套技术,提高故障诊断和远程监控水平;提高技术适应性,通过区块应用,实现工程技术对油藏的调节作用,达到稳油控水、节能降耗的目的,形成"井下工厂"开发新模式,引领"第四代"采油技术的发展。

Progress and prospect of downhole cyclone oil-water separation with single-well injection-production technology

Downhole oil-water separation and single-well injection and production technology is an effective method to realize the economic development of high water cut oilfields. After decades of research and development, several downhole oil-water separation ways have been formed, such as cyclone separation and gravity settlement. Meanwhile, the supporting centrifugal pump, screw pump, sucker rod pump as well as other dynamic systems and packer systems are developed. But many problems still exist in technical stability and reliability. The application scope is affected by medium parameters, process characteristics, reservoir parameters and etc., thus restricting the technical promotion and application. With the advancement of technology, the downhole oil-water separation and single-well injection and production technology is developing to achieve high efficiency, stable operation, small scale, low cost and intellectualization. The axial diversion inlet hydrocyclone has been developed to fit the 139.7 mm(5-1/2 inch) cased well. Research and application is carried out on the cubic curve and endocone hydrocyclones, multistage-series cyclones and other separators, so as to improve the effect of oil and water separation. Modular hydrocyclone technology has been developed to cut down the manufacture cost. The optimized supportive technology for single-well injection and production system has been created to enhance the level of trouble shooting and remote monitoring. The technical adaptability has been improved, and reservoir adjustment has been achieved by block application using engineering technology, so as to stabilize oil production, control water production, save energy and reduce consumption. It is a new "downhole factory" development mode, heralding the development of the fourth generation oil recovery technology.