Systematic Evaluation on Sequestration and Driving Effects by CO2 Injection in Reservoir

As the rapid development of Chinese economy, the demand of electricity increases sharply, which leads to the ascending amount of carbon dioxide released by power plants. Consequently, the treatment and storage of carbon dioxide have become more and more important. Carbon dioxide (CO₂) injection has been used as a commercial process for enhanced oil recovery (EOR). Therefore, CO₂ flooding can not only increase the recoverable reserves of crude oil, but also remove CO₂ accumulated in the atmosphere by storing it permanently. Geological disposal and storage of greenhouse gases should be a thesis which is urgent to be studied in depth. In this paper, literature about CO₂ storage and EOR is investigated, and the latest research trend is summarized. All factors such as reservoirs, fluid property and production method to influence CO₂ flooding and storage are studied by using reservoir numerical simulation. Based on the numerical results of reservoir parameters of the pilot area, comprehensive analysis to the key factors which affecting CO₂ flooding and storage coefficient is carried out, the evaluation parameters affecting CO₂ storage and EOR is determined, the ten dimensionless groups describing reservoir characteristics is derived. According to the relationship between storage or recovery capacity and its influential factors, a model of multivariate regression analyzing was established and used for Geological disposal forecasting. The results showed that method was more precise and accorded with actual instance, which can be used to evaluate the oil recovery and CO₂ storage potential for reservoirs in China and provide criteria for reduction and storage of greenhouse gases.