Open AccessInfluence Study of CO2 Flooding on Formation Oil Parameters in Ultra-Low Permeability Oilfield
Author(s) -
Minghui Li
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/770/1/012026
Subject(s) - petroleum engineering , permeability (electromagnetism) , enhanced oil recovery , relative permeability , light crude oil , environmental science , saturation (graph theory) , water cut , water injection (oil production) , water saturation , water flooding , pilot test , crude oil , materials science , chemistry , geology , composite material , porosity , biochemistry , mathematics , organic chemistry , combinatorics , membrane , psychology , applied psychology
In ultra-low permeability reservoir, the fluid permeability is poor, the productivity is low, and the recovery factor is low in conventional way. As an oil displacement agent, CO 2 has obvious effect of increasing oil and reducing water in oil and gas development. It can not only improve oil recovery, but also store CO 2 and reduce carbon emissions, which has double benefits for environmental protection and oilfield production. CO 2 flooding pilot test was carried out in ultra-low permeability Y oilfield in 2007, which has been developed for 14 years. Through the research and practice of CO 2 flooding in ultra-low permeability oilfield, this paper systematically summarizes the influence of CO 2 injection on formation oil. The results show that: with the increase of CO 2 injection, the rise range of saturation pressure becomes smaller; the dissolved gas oil ratio and expansion coefficient increase, the range becomes larger; the density and viscosity decrease, the range becomes smaller; the minimum miscible pressure of produced fluid in multiple contact decreases gradually. CO 2 can extract light components. With the decrease of light components, the proportion of components above C18 begins to increase, and the main peak carbon is between C13 and C23. At present, the block is in the initial stage of gas breakthrough, and the effect of oil increase is obvious, which provides a reference for the technology and practice of gas injection to enhance oil recovery in other types of reservoirs.