油气藏评价与开发 ›› 2024, Vol. 14 ›› Issue (1): 76-82.doi: 10.13809/j.cnki.cn32-1825/te.2024.01.011

• 矿场应用 • 上一篇    下一篇

新疆油田中深层稠油CO2驱/吞吐实验研究

石彦1(),谢俊辉1,郭小婷1,吴通2,陈德全2,孙琳2,杜代军2()   

  1. 1.中国石油新疆油田分公司准东采油厂,新疆 阜康 831500
    2.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
  • 收稿日期:2023-08-30 出版日期:2024-02-26 发布日期:2024-03-05
  • 通讯作者: 杜代军(1991—),男,博士,助理研究员,主要从事提高采收率理论与技术研究。地址:四川省成都市新都区新都大道8号,邮政编码:610500。E-mail:axiaodu1991@163.com
  • 作者简介:石彦(1970—),女,硕士,高级工程师,主要从事提高采收率技术研究与应用。地址:新疆阜康市准东石油基地准东采油厂,邮政编码:831500。E-mail:524142645@qq.com
  • 基金资助:
    国家自然科学青年基金“致密油藏CO2驱响应性微球体系构建及多级溶胀防窜机理研究”(52304043)

Experimental study on CO2 flooding/huff and puff of medium-deep heavy oil in Xinjiang Oilfield

SHI Yan1(),XIE Junhui1,GUO Xiaoting1,WU Tong2,CHEN Dequan2,SUN Lin2,DU Daijun2()   

  1. 1. Zhundong Oil Production Plant, PetroChina Xinjiang Oilfield Company, Fukang, Xinjiang 831500, China
    2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China
  • Received:2023-08-30 Online:2024-02-26 Published:2024-03-05

摘要:

针对新疆油田中深层稠油油藏的“中等偏强—强”速敏伤害以及“强—极强”水敏伤害引起的注水开发效果不理想的问题,基于CO2独特的物理和化学性质,借助高温高压PVT实验仪和长岩心驱替装置,开展CO2-原油高压物性测定和CO2驱/吞吐提高采收率可行性研究,结合气相色谱和高温高压流变仪表征产出油的组成及黏度变化。实验结果表明,57.345%摩尔分数的CO2能将溶解气油比(GOR)从32 m3/m3增大至149.3 m3/m3、泡点压力(pb)从6.8 MPa增大至15.7 MPa,原油体积系数从1.06增大至1.27,原油密度从0.896 5 g/cm3降低至0.854 8 g/cm3,原油黏度从419.3 mPa·s降低至253.4 mPa·s,因此CO2能有效补充地层能量,增大原油弹性能,减小渗流阻力。第一轮次0.95 PV(孔隙体积)的CO2驱的原油采出程度为32.8%,焖井24 h后多孔介质中的流体重新分布,第二轮次0.5 PV的CO2驱能提高原油采出程度17.9%。而5轮次CO2吞吐的原油采出程度为63.5%。产出油的黏度呈降低的趋势,主要原因是原油中的沥青质在多孔介质中发生沉积。实验结果明确了CO2驱/吞吐在新疆油田中深层稠油提高采收率的可行性。

关键词: CO2驱, CO2吞吐, 溶胀抽提, 提高采收率, 稠油油藏

Abstract:

Addressing the challenges of moderate to strong velocity sensitivity damage and strong to extremely strong water sensitivity damage in the medium and deep heavy oil reservoirs of Xinjiang oilfields, which lead to suboptimal waterflooding outcomes, a study was conducted leveraging the unique physical and chemical properties of CO2. Utilizing high-temperature, high-pressure PVT apparatus and long core displacement equipment, the feasibility of enhancing oil recovery through CO2 flooding/huff and puff was explored by determining the high-pressure physical properties of CO2-crude oil and analyzing the composition and viscosity changes of the produced oil with gas chromatography and high-temperature, high-pressure rheometry. The experimental results show that 57.345% mole fraction of CO2 can increase the dissolved gas-oil ratio(GOR) from 32 m3/m3 to 149.3 m3/m3, the bubble point pressure(pb) from 6.8 MPa to 15.7 MPa, the volume coefficient of crude oil from 1.06 to 1.27, the density of crude oil from 0.896 5 g/cm3 to 0.854 8 g/cm3, and the viscosity of crude oil from 419.3 mPa·s to 253.4 mPa·s. Therefore, CO2 can effectively supplement the formation energy, increase the elastic energy of crude oil and reduce the seepage resistance. The first round of 0.95 PV(pore volume) CO2 flooding has a crude oil recovery of 32.8%, and the fluid in the porous medium is redistributed after 24 hours of shut-in. The second round of 0.5 PV CO2 flooding can increase the crude oil recovery by 17.9%. The crude oil recovery of five rounds of CO2 huff and puff is 63.5%. The viscosity of the produced oil tends to decrease, mainly due to the deposition of asphaltenes in crude oil in porous media. The experimental results have confirmed the feasibility of CO2 flooding/huff and puff in the recovery of heavy oil in the middle and deep layers of Xinjiang Oilfield.

Key words: CO2 flooding, CO2 huff and puff, swelling extraction, enhance oil recovery, heavy oil reservoir

中图分类号: 

  • TE38