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АКАДЕМИЧЕСКОЕ ИЗДАТЕЛЬСТВО «НАУЧНАЯ АРТЕЛЬ»
Annalyyev Palwan
Lecturer International oil and gas university named after Yagshygeldi Kakayev
Hojagulyyev Serdar
Lecturer International oil and gas university named after Yagshygeldi Kakayev
Guzychyyev Atamyrat
Lecturer International oil and gas university named after Yagshygeldi Kakayev
Atayev Yusup
Lecturer International oil and gas university named after Yagshygeldi Kakayev
c. Ashgabat, Turkmenistan
USING A SURFACTANT TO IMPROVE WELL PRODUCTIVITY
Abstract
Declining well productivity is a significant challenge in the oil and gas industry. Surfactants offer a promising approach to improve well output by altering reservoir dynamics. This paper comprehensively reviews the application of surfactants for enhanced oil recovery (EOR). It explores the mechanisms by which surfactants work, including wettability alteration, interfacial tension reduction, and mobilization of trapped oil. The paper then analyzes various surfactant types, their selection criteria, and treatment methods. Case studies demonstrate the effectiveness of surfactant flooding in different reservoir conditions. Finally, the paper addresses current challenges and future directions for surfactant-based EOR, including environmental considerations and integration with other recovery techniques.
Introduction
The global demand for oil and gas necessitates efficient extraction techniques to maximize production from existing reservoirs. As conventional wells mature, their productivity inevitably declines. This necessitates employing enhanced oil recovery (EOR) methods to recover a significant portion of the remaining oil. Surfactants have emerged as a promising class of chemicals for EOR, offering a multifaceted approach to improve well output.
Mechanisms of Surfactant-Enhanced Oil Recovery
Surfactants, or surface-active agents, are amphiphilic molecules possessing a hydrophilic (water-loving) head and a hydrophobic (oil-loving) tail. This unique structure allows them to interact with both oil and water at the oil-water interface, influencing several key mechanisms that enhance oil recovery:
Interfacial Tension Reduction (IFT): Surfactants significantly reduce the interfacial tension between oil and water. Lower IFT allows for easier oil droplet breakup and mobilization within the rock pores. This improves oil flow towards the wellbore.
Emulsion Stabilization: Surfactants can form stable oil-in-water emulsions, preventing oil from adhering to rock surfaces and allowing for its efficient transport to the surface.
Types of Surfactants for EOR
Various types of surfactants are employed in EOR applications, each with distinct properties and functionalities. The selection depends on reservoir characteristics, target oil properties, and economic considerations. Common types include:
Nonionic Surfactants: These uncharged molecules rely on hydrogen bonding for their activity. They are less sensitive to salinity variations compared to ionic surfactants, making them suitable for high-salinity reservoirs.
Selection Criteria for Surfactant EOR Applications
НАУЧНЫЙ ЖУРНАЛ «CETERIS PARIBUS»
ISSN (p) 2411-717X / ISSN (e) 2712-9470
№5 / 2024
Choosing the optimal surfactant for a specific reservoir requires careful consideration of several factors:
Reservoir Characteristics: Factors like rock mineralogy, porosity, permeability, and temperature influence surfactant adsorption and performance.
Oil Properties: Oil viscosity, composition (paraffinic, naphthenic, etc.), and acidity affect surfactant-oil interactions.
Compatibility: Surfactants should be compatible with formation brine and other injected fluids to avoid precipitation or performance reduction.
Environmental Impact: Biodegradable and environmentally friendly surfactants are preferred nowadays.
Cost-Effectiveness: The chosen surfactant should offer a balance between effectiveness and economic viability.
Surfactant Treatment Methods
Surfactants are typically injected into the reservoir through production or injection wells. Common methods include:
Continuous Surfactant Flooding: A continuous stream of surfactant solution is injected into the reservoir. This method is suitable for maintaining a stable interface and maximizing oil displacement.
Pulsed Surfactant Injection (huff-and-puff): Surfactants are injected for a period, followed by a shut-in time to allow for oil mobilization. Production is then resumed to recover the mobilized oil. This method is more economical but may require multiple cycles for optimal results.
Case Studies of Surfactant EOR Applications
Several successful field applications showcase the effectiveness of surfactant EOR:
Daqing Oilfield, China: Anionic surfactants significantly increased oil recovery in this mature carbonate reservoir.
Bodcau Field, USA: Nonionic surfactant flooding resulted in incremental oil production from a sandstone reservoir.
Future Directions in Surfactant EOR Research:
Development of Novel Surfactants: Research focuses on designing more efficient, cost-effective, and environmentally friendly surfactants tailored for specific reservoir conditions.
Nanotechnology Applications: Nanoparticles can be incorporated into surfactant formulations to enhance their stability, adsorption properties, and targeted delivery within the reservoir.
Conclusion
Surfactant flooding offers a valuable tool for enhanced oil recovery. By understanding the mechanisms of action, selecting the right surfactant type, and implementing appropriate treatment methods, significant improvements in well productivity can be achieved. Continuous research and development efforts are crucial to address current challenges and unlock the full potential of surfactant-based EOR for a sustainable and efficient future of oil and gas production. References:
1. Jackson, A. L., Nguyen, Q. P., & Attar, H. (2017). Building a better shale well with biosurfactants improves ultimate recovery. [Society of Petroleum Engineers]. doi: 10.2118/184910-MS
2. Li, S., Sun, Y., Zhang, D., Wang, Y., Guo, K., & Liu, Z. (2020). Evaluation of Surfactant Performance in Fracturing Fluids for Enhanced Well Productivity in the Unconventional Reservoirs Using Rock-on-a-Chip Approach. Energy & Fuels, 34(2), 1222-1233. doi: 10.1021/acs.energyfuels.9b03822
3. Wang, D., Guo, K., Zhao, J., & Li, S. (2018). Optimizing surfactants to improve stimulation flowback in tight gas wells. Journal of Petroleum Science and Engineering, 169, 102-110. doi: 10.1016/j.petrol.2018.06.078
©Annalyyev P., Hojagulyyev S., Guzychyyev A., Atayev Y., 2024
