Investigating and Evaluating Novel Fly Ash-Based Proppant Compressive Strength Under Various Environmental Conditions

As hydraulic fracturing becomes increasingly prevalent in the oil and gas industry, there is a growing need to develop more cost-effective and sustainable technologies, particularly concerning the materials used. Proppants play a vital role in hydraulic fracturing by ensuring that fractures remain conductive and can withstand the pressure exerted by the surrounding strata. One key parameter for evaluating proppants is their compressive strength, especially under harsh environmental conditions. High-strength proppants, such as those made from ceramics or bauxite, are typically expensive due to the materials and complex manufacturing processes involved. In contrast, fly ash, a byproduct of coal-fired power plants, offers a more affordable and environmentally sustainable alternative for proppant production. This study focuses on the development and evaluation of a fly ash-based proppant, exposed to harsh conditions including high temperature and pressure, as well as acidic, alkaline, saline, and crude oil environments. The fly ash was activated using an alkaline solution, which served as a chemical binder for the proppant. After exposure to these conditions, the compressive strength of the fly ash-based proppants was compared to control samples. The results showed that the proppants' compressive strength was largely unaffected by the harsh environments, particularly for the B20W25 mix design. However, while the fly ash-based proppants performed well under stress, their compressive strength was still lower than that of conventional proppants used in the industry. The B20W25 sample demonstrated a compressive strength of 1181.19 psi (8.1 MPa), which, although resilient, remains below industry standards.