特种油气藏 ›› 2022, Vol. 29 ›› Issue (5): 80-87.DOI: 10.3969/j.issn.1006-6535.2022.05.011

• 油藏工程 • 上一篇    下一篇

深层高压碳酸盐岩气藏孔隙结构特征及衰竭开发规律

陈建勋1,2   

  1. 1.中国石化胜利油田分公司,山东 东营 257015;
    2.中国石化胜利油田博士后科研工作站,山东 东营 257002
  • 收稿日期:2021-12-06 修回日期:2022-05-12 发布日期:2023-01-10
  • 作者简介:陈建勋(1991—),男,在站博士后,2014年毕业于吉林大学勘查技术与工程专业,2021年毕业于中国石油大学(北京)油气田开发工程专业,获博士学位,现主要从事致密/页岩油气藏渗流特征研究工作。
  • 基金资助:
    国家科技重大专项“深层碳酸盐岩气藏高效开发技术”(2016ZX05015-003)

Pore Structure Characteristics and Natural Depletion Law of Deep High-pressure Carbonate Gas Reservoirs

Chen Jianxun1,2   

  1. 1. Sinopec Shengli Oilfield Company, Dongying, Shandong 257015, China;
    2. Postdoctoral Research Station, Sinopec Shengli Oilfield, Dongying, Shandong 257002, China
  • Received:2021-12-06 Revised:2022-05-12 Published:2023-01-10

摘要: 深层碳酸盐岩气藏孔隙结构复杂,产能差异大,气藏高效开发和长期稳产面临挑战,急需开展地层条件下衰竭开发规律的针对性研究。为此,采用二级CT扫描技术精细描述了气藏储层的孔隙结构特征,并通过岩心实验研究地层条件下孔隙结构和束缚水对衰竭开发的影响规律。结果表明:孔洞和裂缝的发育与分布不均是该类气藏非均质性强、产能差异大的主要原因;产气量主要受孔隙度的控制,阶段采出程度与渗透率接近对数关系;当井底压力为15 MPa时,孔隙型、孔洞型、裂缝-孔隙型和裂缝-孔洞型储层的平均阶段采出程度分别为47.43%、48.21%、59.90%、62.14%;裂缝-孔洞型储层的储量、产气量、阶段采出程度均相对较高;孔洞型储层的储量高、产气速度低,“高孔低产”特征明显;裂缝-孔隙型储层的储量低、产气速度快,稳产周期短;孔隙型储层的储量和产气速度均比较低。研究结果可为深层高压碳酸盐岩气藏开发方案设计提供理论依据。

关键词: 深层碳酸盐岩气藏, 高温高压, 孔隙结构, 束缚水, 衰竭开发, 阶段采出程度

Abstract: Deep carbonate gas reservoirs with complex pore structure and large variation in productivity challenge the efficient development and long-term stable production, and there is an urgent need to conduct targeted study on the law of natural depletion under stratigraphic conditions. To this end, the pore structure of gas reservoirs was characterized in detail with secondary CT scanning technology, and the influence of pore structure and irreducible water on natural depletion under stratigraphic conditions was investigated by core tests. The results showed that, the uneven development and distribution of pores and fractures was the root cause for the strong heterogeneity and large variation in productivity of this type of gas reservoir; the gas production was mainly controlled by the porosity, and the recovery efficiency was close to a logarithmic relationship with permeability; when the downhole pressure was 15 MPa, the average recovery efficiencies of porous, vuggy, fractured porous and fractured vuggy reservoirs were 47.43%, 48.21%, 59.90% and 62.14%, respectively; the reserve, gas production and recovery efficiency of the fractured porous reservoir were relatively high; the vuggy reservoir was featured by high reserve and low gas production rate, with an obvious characteristic of high porosity and low production; the fractured porous reservoir was characterized by low reserve, fast gas production rate and short stable production period; the porous reserve was relatively low both in reserve and gas production rate. The results of the study provide a theoretical basis for the development plan design of deep high pressure carbonate gas reservoirs.

Key words: deep carbonate gas reservoir, high temperature and high pressure, pore structure, irreducible water, natural depletion, stage recovery degree

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