油气藏评价与开发 ›› 2019, Vol. 9 ›› Issue (4): 19-25.

• 油气藏评价 • 上一篇    下一篇

注采单元地层结垢机理及数值模拟研究

李年银1,康佳1,张昊天1,陶卫东2,任屹3   

  1. 1. 西南石油大学油气藏地质及开发工程国家重点实验室,四川 成都 610500
    2. 中国石油大港油田分公司第四采油厂,天津 300270
    3. 中国石油冀东油田分公司南堡作业区,河北 唐山 063000
  • 收稿日期:2018-10-12 发布日期:2019-08-28 出版日期:2019-08-26
  • 作者简介:李年银(1979 —),男,副教授,博士,从事油气藏增产改造、采油采气工程工作。通讯地址:四川省成都市新都区新都大道8号西南石油大学,邮政编码:610500。E-mail: linianyin@swpu.edu.cn
  • 基金资助:
    国家自然科学基金石油化工联合基金(A类)“复杂碳酸盐岩储层转向酸与固体转向剂协同转向机理研究”(U1762107);国家自然科学基金“多孔介质中酸液的流动反应行为研究”(51574197)

Study on mechanism and numerical simulation of formation scaling in injection-production unit

LI Nianyin1,KANG Jia1,ZHANG Haotian1,TAO Weidong2,REN Yi3   

  1. 1.State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China
    2. No. 4 Oil Production Plant, Dagang Oilfield, CNPC, Tianjin 300270, China
    3. Nanpu Operating Area, Jidong Oilfield, CNPC, Tangshan, Hebei 063000, China
  • Received:2018-10-12 Online:2019-08-28 Published:2019-08-26

摘要:

注水开发是确保油田持续稳产,提高原油采收率最经济、有效的措施之一。然而长期的注水开发过程中地层结垢不可避免,严重影响和制约油田开发效果。以注采单元为研究对象,基于热力学及溶度积规则等理论,考虑地层温度、压力、成垢离子浓度以及流速等因素的影响,建立了注采单元地层结垢数值模型,包括压力场模型、温度场模型、孔隙度与渗透率分布模型以及地层结垢模型,并根据油田实际生产数据,运用MATLAB数学模拟软件进行实例模拟,分析各因素对注采单元内结垢总量、结垢范围、结垢量分布以及地层结垢对视吸水指数和渗透率的影响。结果表明,注水井近井地带温度较低,溶解平衡常数较小且流速大,难以结垢;径向往外,地层温度升高,注入水的流速大幅减缓,最易成垢;继续往外,成垢离子浓度低于最小结垢浓度时,不再结垢。

关键词: 注采单元, 注水井, 结垢模型, 阻垢率, 数值模拟

Abstract:

Water flooding is one of the most economical and effective measures for the sustainable and stable production of oil field and EOR(enhance oil recovery). However, formation scaling is inevitable in the process of long-term water flooding, which seriously affects and restricts the effect of oil field development. Taking injection-production unit as the research object, based on thermodynamic theory and solubility product rule, and considering the influence of formation temperature, pressure, scaling ion concentration and flow rate, the numerical models of formation scaling in injection-production unit was established, including pressure field model, temperature field model, porosity and permeability distribution model and formation scaling model. Meanwhile, according to the actual production data of oil field, mathematical simulation software—MATLAB—was used to carry out the case to analyze the influence of each factor on the total scaling amount, scaling range, distribution of scaling quantity and formation scaling on apparent water absorption index and permeability in injection-production unit. The results showed that the temperature of the immediate vicinity of the injection wells was low, the dissolution equilibrium constant was small and the flow rate was high, so that scaling was difficult. When in radial outward direction, the formation temperature increased, and the flow rate decreased greatly, which made it the most easy condition for scaling. Continue outward, when the scaling ion concentration was lower than the minimum scaling concentration, scale would no longer form.

Key words: injection-production unit, injection well, scaling model, scale inhibition rate, numerical simulation

中图分类号: 

  • TE357