Classification of the temporary plugging agent for diverting fracturing in oil and gas wells according to the condensed state of matter

Temporary plugging agent, effectively preventing the deviation flow of fracturing fluid, is crucial to diverting fracturing in oil and gas wells. Proper classification is conducive to accurately select the temporary plugging agents on site and improve the success ratio of diverting fracturing. Among the temporary plugging agents researched in over 200 literature, some change the pressure patterns in the fracture,some change the rock mechanics parameters, which reduce the energy release rate at the tip of the fracture, and thus improve the pressure bearing capacity of the fracture to realize the diverting fracturing. All temporary plugging mechanisms result from different condensed state of the matter. Therefore, in terms of the condensed state, the temporary plugging agents are classified into three categories: solid, liquid-solid and liquid, including 23 sorts, which covers all temporary plugging agents. And the coverage percentage is increased by 17%. The densities, particle sizes, applicable temperature, unplugging duration, plugging pressure and return permeability of the temporary plugging agent are related to the density and displacement of fracturing fluid, plugging hole diameter or fracture width, reservoir temperature, shut-in and flow-back time, reservoir stress state as well as the physical properties, which improves the accuracy of selection of temporary plugging agent on site.Therefore, classification of the temporary plugging agent for diverting fracturing in oil and gas wells according to the condensed state of matter has addressed the challenges such as lower coverage percentage of the current classification method and inaccurate selection of temporary plugging agents on site.