Abstract: It is an urgent task to reduce atmospheric emissions of carbon dioxide and mitigate global warming. The global capacity, carbon dioxide residence time and the cost for different carbon sinks are introduced. Geological sequestration of carbon dioxide is considered the best choice for near-term reduction of stationary point-source carbon dioxide emission by comparison. The problems to be solved in carbon dioxide geological sequestration are analyzed from chemical engineering and application fundamentals. Under the geological conditions of high temperature and high pressure, the thermodynamic research on complicated multi-phase equilibrium of the system containing carbon dioxide and brine in porous media is a key subject.