TY - JOUR
T1 - Study on seepage characteristics and displacement efficiency of water flooding in offshore heavy oil reservoir
AU - Kun, Xie
AU - Jie, Mei
AU - Narisu,
AU - Erofeev, Vladimir I.
AU - Cheng, Su
AU - Weidong, Jiang
AU - Xiangguo, Lu
N1 - Funding Information:
This work was supported by the Natural Science Foundation of China (No. 51574086, 51834005), National science and technology major projects (2016 ZX05058-003-010), Postdoctoral Innovative Talents Support Program of China (BX20190065).
Publisher Copyright:
© 2020 Tomsk Polytechnic University, Publishing House. All rights reserved.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020
Y1 - 2020
N2 - The relevance. Compared with conventional reservoir, offshore heavy oil reservoir faced the problem of lower water flooding recovery. It is helpful to improve the water flooding recovery of heavy oil reservoir if we have more knowledge about seepage characteristics of water and oil. The main aim of the research is to investigate the change rule of seepage characteristics of water phase and oil phase in offshore heavy oil reservoir, which is helpful to the decision of field construction and can provide guidance for numerical simulation. Methods. The reservoir geological characteristics, fluid properties and field construction technology of the destination offshore heavy oil reservoir in Bohai Oilfield were taken into consideration. The impact of core permeability, injection water washout and crude oil viscosity on relative permeability curve and displacement efficiency of water flooding were studied, through core displacement experiment using displacement method of unsteady state. The change of core inside structure is presented by core CT scanning and mercury pressure test. Results. With the increase of core permeability, water phase relative permeability increases, the swept volume of water phase becomes bigger, two-phase flow span gets wider, and ultimate recovery enhances. The function of cleaning and erosion that water washout exerts on core pore structure would enlarge the pore throat radius, increasing core permeability, and its influence on relative permeability curve and displacement efficiency is the same as the influence of permeability increase. With the crude oil viscosity increasing, mobility control ability of water gets weaker in the process of water flooding, displacement phase viscous fingering phenomenon aggravates, the swept volume of water phase becomes smaller, two-phase flow span gets narrower, and ultimate recovery decreases.
AB - The relevance. Compared with conventional reservoir, offshore heavy oil reservoir faced the problem of lower water flooding recovery. It is helpful to improve the water flooding recovery of heavy oil reservoir if we have more knowledge about seepage characteristics of water and oil. The main aim of the research is to investigate the change rule of seepage characteristics of water phase and oil phase in offshore heavy oil reservoir, which is helpful to the decision of field construction and can provide guidance for numerical simulation. Methods. The reservoir geological characteristics, fluid properties and field construction technology of the destination offshore heavy oil reservoir in Bohai Oilfield were taken into consideration. The impact of core permeability, injection water washout and crude oil viscosity on relative permeability curve and displacement efficiency of water flooding were studied, through core displacement experiment using displacement method of unsteady state. The change of core inside structure is presented by core CT scanning and mercury pressure test. Results. With the increase of core permeability, water phase relative permeability increases, the swept volume of water phase becomes bigger, two-phase flow span gets wider, and ultimate recovery enhances. The function of cleaning and erosion that water washout exerts on core pore structure would enlarge the pore throat radius, increasing core permeability, and its influence on relative permeability curve and displacement efficiency is the same as the influence of permeability increase. With the crude oil viscosity increasing, mobility control ability of water gets weaker in the process of water flooding, displacement phase viscous fingering phenomenon aggravates, the swept volume of water phase becomes smaller, two-phase flow span gets narrower, and ultimate recovery decreases.
KW - Heavy oil reservoir
KW - Offshore oilfield
KW - Oil recovery
KW - Relative permeability
KW - Unsteady state method
KW - Water flooding
UR - http://www.scopus.com/inward/record.url?scp=85095439278&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85095439278&partnerID=8YFLogxK
U2 - 10.18799/24131830/2020/10/2855
DO - 10.18799/24131830/2020/10/2855
M3 - Article
AN - SCOPUS:85095439278
VL - 331
SP - 105
EP - 114
JO - Bulletin of the Tomsk Polytechnic University, Geo Assets Engineering
JF - Bulletin of the Tomsk Polytechnic University, Geo Assets Engineering
SN - 2500-1019
IS - 10
ER -