At present

the oil recovery in the CO

2

oil displacement area of the peripheral oilfields in Daqing is mainly predicted by numerical simulation with no empirical formulas. In order to solve this problem

firstly

an heterogeneous ideal model of miscible

near-miscible and immiscible by CO

2

flooding based on the basic physical properties and PVT parameters of the peripheral oil field in Daqing oilfield is established. Secondly

three kinds of characteristic curves of CO

2

flooding are defined

including carbon content-accumulation of oil

type A and type B. The feature curve is used to predict the r

ecovery rate in the model

and the calculation method of characteristic curve suitable for CO

2

near-miscible flooding modes is optimized. On this basis

the carbon content and recovery degree chart suitable for S block is established

and compared with the actual performance of S block. A-type gas drive characteristic curve is selected for the further establishment of the CO

2

near-miscible drive chart

and this improved chart is applied to predict the recovery rate of S block. The results show that the recovery rate predicted by the CO

2

near-miscible flooding chart is close to that predicted by the field test of S block. This method can predict the recovery rate of CO

2

flooding simply and quickly

and has guiding significance for the next development and evaluation of S block and similar blocks.