Tight oil reservoir co2 flooding multi-scale channeling control system and preparation method

A tight oil reservoir CO2 flooding multi-scale channeling control system, comprising nanoscale CO2 responsive worm-like micelle system and micron-scale CO2 responsive dispersion gel;

• wherein, in mass percent, the micron-scale CO2 responsive dispersion gel are prepared by cross-linking the following components:
• acrylamide 15%-25%;
• responsive monomer 3%-8%;
• silane coupling agent modified hydroxylated multi-walled carbon nanotubes 0.05%-0.1%;
• initiator 0.01%-0.1% of total monomer mass;
• cross-linking agent 0.5%-2% of the total monomer mass;
• and
• water, wherein the total mass percent of the components is 100%;
• the preparation method of the micron-scale CO2 responsive dispersion gel is:
• after the silane coupling agent modified hydroxylated multi-walled carbon nanotubes are dispersed uniformly in water by ultrasonic waves, under the condition of stirring speed of 300-500 r/min, the acrylamide, responsive monomer, initiator and cross-linking agent are respectively added to the solution;
• N2 is injected into the solution until the solution becomes viscous, and a thermometer is used to monitor the temperature change of the solution, until the temperature of the solution rises to a highest temperature when cooling down starts, the solution is kept in thermal insulation for 2-4 hours under the condition of the highest temperature of the solution to obtain a black gel;
• micron-scale CO2 responsive dispersion gel is obtained after granulation, drying and pulverization of the black gel;
• wherein, the responsive monomer is N-methyl-N-vinylformamide, N,N-diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, or a combination thereof;
• wherein, the nanoscale CO2 responsive worm-like micelle system is prepared by cross-linking the following components:
• CO2 responsive monomer 30-90 mmol/L;
• organic counter ion monomer 30-90 mmol/L;
• and
• a solvent comprising water;
• the preparation method of the nanoscale CO2 responsive worm-like micelle system is:
• CO2 responsive monomer is completely dissolved in water to formulate CO2 responsive monomer solution, under the condition of stirring speed of 300-500 r/min, the organic counter ion monomer is added with the same amount of the CO2 responsive monomer to the CO2 responsive monomer solution, and the solution is stirred at room temperature to obtain uniform nano-scale CO2 responsive worm-like micelle system;
• wherein the CO2 responsive monomer is N,N-dimethylcyclohexylamine, N,N-dimethylbenzylamine, N,N-dimethylbutylamine, tetramethylethylenediamine, trimethylamine, N,N-dimethyloleoaminde-propylamine, diethylenetriamine, cocoyl dimethyl tertiary amine, erucic acid amidopropyl dimethyl tertiary amine, or a combination thereof;
• the organic counter ion monomer is sodium p-styrenesulfonate, sodium dodecylbenzenesulfonate, sodium p-toluenesulfonate, sodium oleate, or a combination thereof.