海上稠油油田层间干扰变化研究

Study on interlayer interference changes in offshore heavy oil reservoirs

 张浩¹ 李廷礼² 贾晓飞² 季赟³

西南石油大学石油与天然气工程学院，四川 成都 610500 中海石油（中国）有限公司天津分公司，天津 300452 中国石油青海油田公司勘探开发研究院，甘肃 敦煌 736202

School of Petroleum and Nature Gas Engineering, Southwest Petroleum University, Chengdu 610500, China Tianjin Branch of CNOOC Ltd., Tianjin 300452, China Research Institute of Exploration and Development, Qinghai Oilfield Company,
PetroChina, Dunhuang 736202, China

 X油田为海上多层稠油油田，为了保证单井的经济产量，实行多层合注合采。但是随着开采的进行，层间差异增大，层间干扰变严重，一个显著的特征就是高渗层的产液量和吸水量越来越多，低渗层的产液量和吸水量却越来越少，导致高渗层大量产水，而低渗层的原油无法有效采出。如何预测层间干扰增大到一定程度时的层系细分时机，是X油田面临的重要问题。文中推导了预测高渗层与低渗层产液干扰的公式，从机理上说明开采过程中层间干扰变大的原因是高渗层的含水饱和度上升速度大于低渗层。在此基础上，定义了米产液指数比和米产液指数倍增比，定量描述层间干扰程度的变化情况，得到了预测分层开采时机的图版，并与实际产液测试结果进行了对比。该图版具有较高的预测精度，可以避免X油田为了层系调整而做大量的产液测试工作，节约了大量开发成本，对稠油多层合注合采油田后期层系调整和层系细分具有指导意义。

 In order to guarantee economic production, commingled injection and production are applied in X Oilfield for offshore heavy oil reservoirs. However, interlayer difference and interference are increasing in the oilfield development. The problem is that the high permeable layers have more and more liquid production and water absorption but the low permeable layers have less and less, which causes high permeable layers produce water seriously and low permeable layers can’t produce oil effectively. How to forecast the time when interlayer interference surpasses some extent is very critical. In this paper, liquid interference formula was deduced, which indicates that interlayer interference increasing is caused by the faster water saturation of high permeable layers. And the forcastion precision was proved by numerical simulation. Based on this, liquid productive index per meter ration and liquid productive index per meter increasing ration were defined for describing quantitatively degree of interlayer interference change. And the diagrams for forecasting time of zonal production and injection were acquired for guiding X Oilfield development scientifically, avoiding mountains of zonal test work and saving much development cost. It is significant for guiding layer adjustment and subdivision when commingled injection and production is in the late development period in heavy oil oilfield.

10.6056/dkyqt201505024