In the relentless pursuit of optimizing oil recovery, a groundbreaking study has emerged from the Shaanxi Key Laboratory of Chemical Additives for Industry, led by Haoxuan Zheng. This research, published in the Journal of Petroleum Exploration and Production Technology, delves into the intricate dance of oil, water, and solid interfaces in high-salinity co-produced water systems. The findings could revolutionize how we approach low-permeability and high-salinity reservoirs, offering a more cost-effective and efficient path forward.
At the heart of this study lies the synergistic relationship between chelating agents and surfactants. These chemical compounds, when combined, exhibit remarkable properties that could significantly enhance oil recovery processes. The research team focused on Sodium isomeric 13-alcohol polyoxyethylene ether sulfonate itaconic acid ester (GTOS), a surfactant that demonstrated exceptional performance in reducing oil-water interfacial tension and altering rock wettability. “GTOS at a concentration of just 0.3% can reduce the oil-water interfacial tension to an astonishing 10⁻2 mN/m,” Zheng explains. This dramatic reduction facilitates the separation of oil from water, a critical step in the oil recovery process.
Complementing GTOS is N, N-diacetic acid (GLDA), a chelating agent that effectively neutralizes metal ions on the rock surface. GLDA not only achieves a scale inhibition rate of 98% but also modifies rock wettability, making it more conducive to oil recovery. When GLDA and GTOS are combined, their synergistic effects are even more pronounced. “The combination of GLDA and GTOS is more effective at reducing oil-water interfacial tension and modifying rock wettability than either agent alone,” Zheng notes. This synergy is crucial for enhancing recovery in challenging reservoirs.
The study employed advanced microscopic techniques to analyze variations in crude oil bonding, rock surface roughness, and charge adsorption. These analyses provided deep insights into the synergistic effects of the agents, confirming significant oil film removal from the rock surface following treatment. Spontaneous seepage experiments further validated the formulation’s effectiveness, showing a 36% increase in crude oil self-absorption recovery in the rock.
One of the most compelling aspects of this research is its cost-effectiveness. The formulation utilizes lower concentrations of chemicals than previous studies, making it more economical for field applications. This is a game-changer for the energy sector, where cost efficiency is paramount.
The implications of this research are far-reaching. By understanding the synergistic mechanisms of chelating agents and surfactants, the energy industry can develop more effective strategies for enhancing recovery in low-permeability and high-salinity formations. This could lead to increased oil production, reduced operational costs, and a more sustainable approach to energy extraction.
As the energy sector continues to evolve, innovations like this will be crucial in meeting the growing demand for oil while minimizing environmental impact. The work of Haoxuan Zheng and the team at the Shaanxi Key Laboratory of Chemical Additives for Industry, published in the Journal of Petroleum Exploration and Production Technology, offers a glimpse into the future of oil recovery. It is a testament to the power of scientific inquiry and the potential for chemical innovation to drive progress in the energy sector. As we look ahead, the insights gained from this study could pave the way for new technical approaches and a more efficient, sustainable future for oil production.
