Feasibility Study On CO 2 Subcategory For Dry Gas Storage

In recent years, the tendency of global warming is becoming more serious. Effective technological ways of reducing carbon dioxide and other greenhouse gas emission have drawn people’s more and more attention. Using carbon dioxide as cushion gas can not only accomplish the mission of carbon sequestration, but also replace natural gas as cushion gas precipitating in reservoirs, and exert its function of pressure maintenance. This article will study some technical problem concerning carbon dioxide being used as cushion gas in depleted underground gas storage:First, the gas reservoir types of studies are depleted gas reservoir, the geological conditions of this underground storage have been fully explored which can reduce the building database cycle, at the same time some facilities in the oil filed can be reused to reduce the initial investment, and more importantly, there is generally a small amount of residual gas in the depleted gas storage, which part can be directly used as cushion gas, so that economic efficiency can be improved.Secondly, the feasibility of carbon dioxide used as the cushion gas in the gas reservoir is studied. Research on the physical properties of carbon dioxide proves that carbon dioxide is a kind of supercritical fluid at the usual condition of gas reservoir. Compared with natural gas, it has the characteristics of high condensability, high viscosity and high density which are benefited for cushion gas. High condensability can maintain the pressure of reservoir; high viscosity can avoid the mixing with working gas; High density can arouse gravity segregation phenomena.Finally, this paper researches the sensitivity of the mixing between CO2and natural gas by numerical simulation, finds out the main factors influencing the mixing, proves the great influence of dynamic injection-production on mixing. It’s shown that it’s better to inject cushion gas from the side of reservoirs. This paper recommends using quantitative production in practical engineering operations.Using CO2as cushion gas for depleted gas reservoir can not only economize capital but also realizable carbon sequestration and decrease greenhouse effect. This paper will mainly aim at a series of technological issues concerning using carbon dioxide as the cushion gas of reservoirs. Supplies theory gist and technical support for carbon sequestration and putting up of underground gas storage in china.It has an important significance.