海上高含水大液量水平井凝胶堵水数值模拟

Numerical simulation of gel water shutoff in offshore horizontal wells with high water cut and large flow

万小进 黎棚武 吴绍伟 彭东宇 程利民 贾虎

中海石油（中国）有限公司湛江分公司，广东 湛江 524057 西南石油大学油气藏地质与开发工程国家重点实验室，四川 成都 610500

Zhanjiang Branch of CNOOC Ltd., Zhanjiang 524057, China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China

复杂条件下的水平井化学堵水不可控因素多，施工条件苛刻，堵水成功率低。针对这些问题，文中采用物理实验及数值模拟，开展岩心尺度纳米酚醛凝胶堵水效果研究，建立了考虑交联反应、吸附理论的凝胶堵水机理模型，通过实验数据拟合，获取了Langmuir 等温吸附系数、岩石最大吸附量和残余阻力系数等关键参数。 以文昌19￣1油田典型大液量（大于1 000 m3）、高含水率（大于90%）水平井——A8H1井为例，通过近井地带网格加密建立单井堵水数值模型，开展水平井凝胶堵水效果影响因素研究。结果表明：堵剂用量受实际油藏岩石的吸附水平限制，A8H1井最优堵剂用量为250 m3；油井含水率越低，生产压差和地层渗透率级差越小，水平井凝胶堵水效果越好。研究成果可为类似复杂水平井凝胶堵水选井及工艺方案设计提供参考。

The chemical water shutoff of horizontal wells under complex conditions has many uncontrollable factors, harsh construction conditions and low water shutoff success rate. For these problems, the physical experiment and numerical simulation are used in this paper. The water shutoff effect research with nano phenolic gel in core dimension is carried out, and the gel water shutoff mechanism model is set up by considering the crosslinking reaction and adsorption theory. Then, the Langmuir isotherm adsorption coefficient, rock maximum adsorption and residual resistance factor are obtained by fitting experiment data. Taking Well A8H1, a horizontal well with large flow (>1,000 m3) and high water cut (＞90%), in Wenchang 19-1 oilfield as an example, the numerical model of water shutoff in single well is established by grid infusing near well zone for studying the influencing factors of gel water shutoff effect in horizontal well. The results show that the optimal drug dosage for well A8H1 is 250 m3, which is limited by the adsorption level of actual reservoir rocks. The smaller the water cut of the oil well, the lower the production pressure difference and formation permeability ratio, and the better the gel water shutoff effect of horizontal well. The research results can provide guidance for the selection of target wells for gel water shutoff and the design of technological scheme in the similar complicated horizontal wells.

10.6056/dkyqt202303014