油气藏评价与开发 ›› 2020, Vol. 10 ›› Issue (2): 60-64.doi: 10.13809/j.cnki.cn32-1825/te.2020.02.010

• 油气藏开发 • 上一篇    下一篇

高温高压缝洞型油藏注N2驱提高采收率机理研究及实践

谭涛1,2,郭臣1,2,陈勇1,2,窦莲1,2,惠健1,2   

  1. 1.中国石化西北油田分公司勘探开发研究院,新疆 乌鲁木齐 830011
    2.中国石化碳酸盐岩缝洞型油藏提高采收率重点实验室,新疆 乌鲁木齐 830011
  • 收稿日期:2019-10-10 出版日期:2020-04-26 发布日期:2020-04-28
  • 作者简介:谭涛(1981—),男,硕士,高级工程师,从事油气藏提高采收率技术研究,通讯地址:新疆乌鲁木齐市长春南路466号中石化西部科研园西北石油局勘探开发研究院。邮政编码:830011,E-mail: 17928945@qq.com
  • 基金资助:
    “十三五”国家科技重大专项“塔里木盆地碳酸盐岩油气田提高采收率关键技术示范工程”(2016ZX05053)

Study and practice on mechanism of EOR by N2 flooding in fractured-vuggy reservoirs with high temperature and high pressure

TAN Tao1,2,GUO Chen1,2,CHEN Yong1,2,DOU Lian1,2,HUI Jian1,2   

  1. Research Institute of Exploration and Development, Sinopec Northwest Oilfield Company, Urumqi, Xinjiang 830011, China
    2.Key Laboratory for EOR of Carbonate Fractured-Vuggy Reservoir of Sinopec, Urumqi, Xinjiang 830011, China
  • Received:2019-10-10 Online:2020-04-26 Published:2020-04-28

摘要:

塔河油田碳酸盐岩缝洞型油藏具有复杂的地质特征,主要体现在储层发育有孔、缝、洞多种形态,空间展布连续性差,组合模式复杂,表层岩溶系统经风化淋漓形成残余缝洞储集空间。开发中底水易沿高角度裂缝窜进形成水锥,水窜通道外井间剩余油与残丘封存的“阁楼油”大量富集。前期通过物理模拟明确了缝洞型油藏注N2利用密度差进行重力置换宏观机理,但对于置换的“阁楼油”和井间剩余油的驱替机理还不明确,通过开展模拟塔河缝洞型油藏55 MPa和130 ℃条件注入N2对原油物性影响实验,揭示了注N2在高温高压油藏条件下对原油的溶解膨胀增能、抽提溶解等微观作用机理,基于缝洞地质刻画成果制作可视化物理模型,通过可视化观察井间注N2过程中重力置换和抑制水锥的驱替机理,经过现场实践进一步证明了技术的可行性和推广潜力。

关键词: 缝洞型油藏, N2, 阁楼油, 重力置换, 水锥, 提高采收率

Abstract:

Carbonate fractured-vuggy reservoirs in Tahe oilfield have complex geological characteristics, which is mainly reflected in the various forms such as pore, fracture and cave developed in the reservoir, poor continuity of spatial distribution, complex combination mode, and the residual fracture-vuggy storage space formed in surface karst system by weathering. During the development, it is easy to form the bottom water coning along the high angle crack. The remaining oil between the wells outside the water channels and the “attic oil” stored by the residual fault are enriched in large quantities. In the earlier stage, the macroscopic mechanism of gravity displacement by using density difference in N2 injection of seam-hole reservoir is clarified by means of physical simulation. However, the displacement mechanism of the “attic oil” and the residual oil between wells is not clear. Through the simulation experiments of the effects of the injected N2 on the physical properties of crude oil under the conditions of 55 MPa and 130 ℃, the micro mechanism such as the effects of N2 on dissolution, expansion, capacity increase, extraction and dissolution of crude oil under the condition of high temperature and high pressure reservoir. Based on the fractured-vuggy geological characterization, visual physical model is made to observe the displacement mechanism of gravity displacement and water coning suppression during N2 injection. After field application, the feasibility and popularization potential of the technology are further proved.

Key words: fractured-vuggy reservoir, N2, attic oil, gravity displacement, water coning, EOR

中图分类号: 

  • TE357