Abstract: Under the long-term fracturing of tight/shale oil and gas, where preferential channeling migration pathway developed, the dispersed particle gels has excellent performance effects in the control of the flow channel and expansion of the sweeping. Dispersed particle gels have excellent effects in improving the heterogeneity of tight oil/shale oil and gas reservoirs. A close relationship lies between the mechanical strength of the dispersed particle gels and their macro plugging performances. However, currently there is no effective method for characterization of the mechanical strength of the dispersed particle gels. Tacking the chromium crosslinked dispersed particle gels have been chosen as the examples, We measured the Young's modulus of dispersed particle gels at the nano and micro scales by atomic force microscope, and the mapping relationship between them is established by evaluating its macroscopic plugging performances. The research results indicate that when the fixed mass fraction of polymer is 0.3% and the mass fraction of SD-107 increases from 0.4% to 0.7%, the strength of the bulk gels increases, and the Young's modulus of the corresponding dispersed particle gels also increase. When Young's modulus increases from 159 Pa to 633 Pa, the plugging rate can rise from 93.23% to 98.08%. In this study, the Young's moduli of micro and nano scale dispersed particle gels are adjusted to study the difference in plugging performances, which provides theoretical foundation for the efficient development of tight/shale oil and gas reservoirs.

Key words: dispersed particle gels, Young's modulus, plugging performance, crosslinked polymer gel, rheological properties