杏六西区块两三结合后聚驱井网搭建再利用

Construction and Reuse of Polymer Flooding Well Network after Two Tertiary Combination of Xing6 West Block

摘要: 为保证杏北开发区产量接替，自2015年以来不断开展三类油层化学驱现场实验，杏六区西部作为首个两三结合后聚驱井网水驱利用的实验区块，急需明确变流线后的聚驱井网搭建与再利用方法，以达到精细挖潜剩余油、提高油气采收率的目的。本文针对杏六西地质特征及开发状况，提出了两三结合后聚驱井网搭建与再利用设想，并进行可行性分析，通过数值模拟方法，明确了聚驱井网上返层系重组调整界限和分步射孔方式。研究结果表明，两三结合后聚驱井网搭建与再利用方法可实现转流线90度，聚驱井网开发层系确定为萨III7~葡I2₁²，并针对该层段层间差异大的特点，提出了先射开萨III7-11油层和砂岩厚度小于2.5 m的萨III7~葡I2₁²油层再射开葡I1~2油层的射孔方案，阶段采出程度为4.83%，与现井网相比采收率提高了1.83个百分点，该成果将指导后续大庆油田杏北开发区三类油层化学驱的聚驱井网调整。

Abstract: In order to ensure the production replacement of Xingbei development zone, the field experiment of chemical flooding in three types of oil layers has been carried out since 2015. As the first experi-mental block of water flooding utilization of polymer flooding well network after two tertiary com-bination, the western part of Xing6 area urgently needs to clarify the construction and reuse meth-od of polymer flooding well network after the streamline. Based on the geological characteristics and development status of Xingliuxi, this paper puts forward the idea of building and reusing the polymer flooding well network after two tertiary combination, and carries out feasibility analysis. Then, through numerical simulation research, the adjustment boundary of the re-layering system and the step perforation method of the polymer flooding well network are clarified. The research results show that the construction and reuse method of polymer flooding well network after two tertiary combination can realize the flow line of 90 degrees, and the development layer of polymer flooding well network is determined to be SIII7~PI2₁². According to the characteristics of the large difference between the layers, the perforation scheme of first shooting open the oil layer of SIII7-11 and the oil layer of SIII7~ PI2₁² with sandstone thickness less than 2.5 m and then shooting open the oil layer of PI1-2 is proposed. The stage recovery degree is 4.83%, and the recovery rate is in-creased by 1.83 percentage points compared with the current well network. The results will guide the adjustment of polymer flooding well network for chemical flooding in the three types of reser-voirs in Xingbei Development Zone of Daqing Oilfield.