Carbon dioxide sand mulling oil production process for oilfield and special carbon dioxide sand mulling device

The invention belongs to a liquid-phase carbon dioxide and quartz sand mixed injection rock stratum process and a sand mulling device in a tertiary oil production process of an oilfield oil production process. The uniformly-mixed liquid-phase carbon dioxide and solid quartz sand are simultaneously injected into an oil well rock stratum through a high-pressure pump with pressure of 40-60MPa and are fully reacted under the condition of oil reservoir to release carbon dioxide gas. The carbon dioxide is dissolved into crude oil, the viscosity of crude oil is reduced, and the crude oil volume is expanded. The solid quartz sand as a support material enters a stratum along with a high-pressure solution to be filled into the cracks of the rock stratum to play a role of supporting the cracks not to be closed due to stress release, so that a high-conductivity capacity is kept, and oil and gas are unrestricted. The invention provides the sand mulling device at the same time. According to the process, the viscosity of crude oil can be reduced, the crude oil volume can be expanded, meanwhile, the solid quartz sand is filled into the cracks of the rock stratum to play the role of supporting the cracks not to be closed due to the stress release, so that the high-conductivity capacity is kept, the oil and the gas are unrestricted, and the yield is increased.