Numerical Simulation of Geochemical Compatibility of Biomass-Derived Alkaline Agents for Enhanced Oil Recovery Applications

This study presents a comprehensive numerical investigation of the geochemical compatibility of a biomass-derived alkaline agent, Date Palm Ash (DPA), for enhanced oil recovery (EOR) applications. The DPA solution (1 wt.%, pH = 11.87) was modelled as a mixed alkaline system containing Ca(OH)₂, NaOH, KOH, and Mg(OH)₂ and equilibrated with carbonate (pH = 5.81) and sandstone (pH = 6.16) formation brines over temperatures of 25–100 °C at 3000 psig using coupled geochemical–reservoir simulation. Results show that in carbonate formations, maximum calcite (613 ppm) and barite (14 ppm) precipitation occurred at a DPA fraction of 0.2, with calcite relatively insensitive to temperature, while barite decreased sharply and disappeared at 100 °C. In sandstone formations, initial calcite concentration was negligible and increased progressively with DPA fraction, reaching its maximum near 0.8 fraction, with no observable barite precipitation. Reservoir simulations further demonstrated higher permeability impairment and calcite adsorption in carbonate reservoirs, leading to lower fractional oil recovery (~0.58) compared to sandstone reservoirs (~0.62). Three-dimensional analyses revealed more pronounced permeability reduction and mineral deposition in carbonate systems, whereas sandstone formations maintained higher productivity indices and lower salinity effects. Overall, DPA exhibited superior geochemical compatibility and flow performance in sandstone reservoirs. The findings confirm the technical feasibility of utilizing biomass-derived alkaline solutions as sustainable alternatives to synthetic alkalis, while emphasizing the importance of lithology-specific compatibility assessment to mitigate scale formation and formation damage in alkaline EOR processes.