Recent advancements in hydraulic fracturing technology have significantly improved the extraction of hydrocarbons and geothermal energy from unconventional reservoirs. This study evaluates the performance of various proppant materials, including petroleum coke-based proppants (PC), high-transported ultra-low-density ceramic proppants (LDC), and resin-coated ceramic proppants (RC), focusing on their crush resistance and packing strength under simulated downhole conditions. Using the Standard procedure outlined in API ISO 13503-2, we assessed both dry proppants across two mesh sizes (10/35 and 35/60) and wet proppants that were exposed to high temperatures (300 °C) for 7, 14, and 30 days to simulate geothermal environments. The proppants were subjected to heat in the presence of water. The findings of the dry test demonstrate that, although petroleum coke-based proppants are less expensive, they are not as strong as ceramic proppants. Ceramic proppants coated with resin, on the other hand, demonstrate remarkable stress tolerance that surpasses 15,000 psi. Furthermore, the study shows that, depending on the type and size of proppant, the crush resistance and packing strength of proppants often decrease with time when subjected to high temperatures. Specifically, petroleum coke-based proppants demonstrated minimal reduction in strength after heat exposure, while ceramic-based proppants exhibited a more pronounced decrease in mechanical performance. Moreover, dry crush tests conducted on mixtures of PC with LDC and PC with RC at various proportions (at a stress level of 5,000 psi) shown that a mix of PC with LDC or RC substantially decreases the generation of fines, lowers compaction, and improves the overall mechanical properties of PC proppants. The findings emphasize the significance of taking temperature effects into account when selecting proppants for geothermal applications, particularly those that are ceramic-based, given the critical impact of prolonged high-temperature exposure on their mechanical integrity.

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