Generation Of Reservoir Conditions Of Co <sub> 2 </ Sub> Co <sub> 2 </ Sub> Flooding Experiment

Miscible/Immiscible carbon dioxide injection is considered to be as one of most effective technology to improve oil recovery from complicated formations, and hard to recover oil reserves, in particular. Application of this technology can increase ultimate oil recovery by 10%-15% and even more. One of the main advantage of this technology is that it can be applied in a wide range of geological conditions for production both light and heavy oils.One of the main factor restraining wide application of this technology is its dependence on the natural CO₂ sources, transportation of CO₂, breakthrough of CO₂ to production wells, corrosion of well and field equipment, safety and environmental problems etc. One of the main advantage of proposed technology is eliminating of CO₂ negative impact on the environment and strong control of the process.In order to solve the above problems, the paper brings forward two in-situ generation CO₂ systems: single liquid system and double liquids system. The single liquid system is based on heating the single compound to decompose CO₂,and the double liquids system is based on exothermic chemical reaction between gas forming water solution and low concentrated active acids.The displacement property (contained:the quantum of gas, dilation efficiency, the degree of viscosity reduction) and displacement efficiency of the two systems have been evaluated. The results indicate, on the condition of oil field, both single liquid system and double liquids system can generate enough Carbon Dioxide gas.Besides, when the viscosity of oil is 6631.24mPa.s, the single liquid system can expanse the oil by 20%, reduce the viscosity of oil by 42.15%;and the double liquids system can expanse the oil by 32.5 %, reduce the viscosity of oil by 52.69%, which show CO₂ dissolution in crude oil have better expansion efficiency and better viscosity reduction efficiency. The core flowing tests indicate, when injecting 0.1 PV reacting liquid, single liquid system can enhance oil recovery by 7.4%-10.8%,and the double liquid system can enhance oil recovery by 6.4%-17.06% , which show both single liquid system and double liquid system have better displacement efficiency. According the require of test, a set of facility liquid dilation instrument have been designed, which give a research approach to appraise dilation efficiency of crude oil; by the definition of resistance coefficient and it's theory of mensurating, the paper first bring forward the test method using resistance coefficient to measure viscosity reduction of crude oil. In addition, this technology does no harm to the formation.It is clear that development of technology where displacement agent to displace oil from formation (CO2) is generated in-situ avoiding any surface facility and any negative impact on the environment has a high priority.