To solve the problems of difficult miscibility and low sweep coefficient in CO

2

flooding of ultra-low permeability beach-bar sand reservoir

theories and methods such as geology

seepage mechanics and reservoir engineering and by the combined methods of physical modeling and mathematical simulation are used to formulate the evaluation standard of CO

2

flooding

clarify the EOR mechanism of CO

2

flooding

form the optimum design technique adapted for the well pattern of CO

2

flooding

and optimize the policy limitation of CO

2

flooding in the demonstration zone Gao 89-1 block. It is indicated that the technology has been applied effectively. Up to now

over 2

.8×10

5

t of CO

2

have successfully been injected into the reservoir

and the cumulative oil increment is 6.5×10

4

t

and 2.6×10

5

t of CO

2

have been stored in CO

2

flooding and storage demonstration zone.