稠油热采闭式热流体循环井筒温度场分析

Analysis of the Wellbore Temperature Field in Closed Thermal Fluid Circulation for Heavy Oil Thermal Recovery

针对"两高"油田原油流动性差的特点以及闭式热流体循环降粘工艺的复杂性,建立了3种闭式热流体循环井筒传热模型及其边界条件,并采用Matlab编写了相应的模型求解程序。通过对现场具体井眼进行模拟计算,对比分析了3种闭式热流体循环效果,给出了最优热流体循环方案。计算了循环流量、循环介质和管柱材料物性参数等对井筒加热效果的影响。计算结果表明,两侧加热方案最好,随着循环流量的增加井筒温度不断升高,导热油作为循环热载体较好,导热性能差的管柱材料能够提高循环加热段产液流动的平均温度。

In light of the poor fluidity of crude oil in ＂two-high＂ oilfields and the complexity of viscosity reduction of closed thermal fluid circulation, three wellbore heat transfer models for closed thermal fluid circulation and the boundary conditions were established. The Matlab was adopted to compile the corresponding model solution program. Through simulation calculation of the specific field holes the circulating effect of the three closed thermal fluids was compared and the optimal thermal fluid circulation scheme was given. The effect of the parameters such as circulating flow rate, circulating medium and pipestring material property on wellbore heating effect was analyzed. The calculation shows that the scheme of heating on both sides is the best. With the increase of circulating flow rate the wellbore temperature increases constantly. It is better to use heat conducting oil as the circulating heat carrier. The pipestring material with poor heat conductibility can improve the average temperature of produced fluid flow at the circulating heating section.