Petroleum Reservoir Evaluation and Development ›› 2021, Vol. 11 ›› Issue (6): 871-877.doi: 10.13809/j.cnki.cn32-1825/te.2021.06.011

• Field Application • Previous Articles     Next Articles

Field test effect analysis of CO2 huff and puff for EOR of horizontal wells in tight glutenite reservoir of Mahu Oilfield

SHI Leiting1(),ZHANG Yulong1,YE Zhongbin1,3,ZHANG Jing2,WANG Yingwei2,WANG Ruiqi1,WU Sitong1   

  1. 1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China
    2. Research Institute of Exploration and Development, CNPC Xinjiang Oilfield Company, Karamay, Xinjiang 834000, China
    3. Chengdu Technological University, Chengdu, Sichuan 610500, China
  • Received:2021-07-07 Online:2021-12-26 Published:2021-12-31

Abstract:

The porosity and permeability of Mahu sandy conglomerate tight reservoir in Xinjiang are extremely low. After fracturing and putting into production, the stable production effect of early development is good, and the decline is large in the later stage. In order to supply the formation energy and improve the crude oil recovery, the tests of CO2 huff and puff for three horizontal wells have been carried out in Ma131 well area. The test results show that the mechanism of CO2 huff and puff to improve crude oil recovery is mainly reflected in increasing reservoir energy, expanding crude oil volume, reducing crude oil viscosity, extracting light components, dissolving reservoir minerals and increasing fluid flow capacity. Reasonable injection parameters are more helpful to enhanced oil recovery. During the development of CO2 huff and puff, the higher bottomhole injection pressure and the longer soaking time, as well as greater sweep diffusion, result in earlier continuous oil production and more obvious enhanced oil recovery effect. The oil increment of three horizontal wells, Well-X721, Well-X92 and Well-M1114, is 2 161 t, 1 768 t and 1 452 t, respectively. CO2 huff and puff has good adaptability and popularization and application prospect in sandy conglomerate tight reservoir.

Key words: sandy conglomerate, tight reservoir, enhanced oil recovery, CO2 huff and puff, field test

CLC Number: 

  • TE357