Experimental and theoretical investigation of a double-chamber pneumatic pump for shaft well rehabilitation

This study presents the development, theoretical analysis, and experimental validation of a double-chamber pneumatic pump designed to improve the efficiency of shaft well rehabilitation in rural water supply systems. Shaft wells remain a critical source of water in arid and semi-arid regions, however, their performance is often compromised by sediment accumulation and insufficient maintenance. To address this challenge, a novel mobile system integrating hydraulic jetting, pneumatic agitation, and hydrocyclone-based separation was developed. An analytical model based on multiphase flow and pneumatic transport principles was established to predict discharge capacity, pressure requirements, and energy consumption. The model was validated through laboratory experiments conducted at lifting heights of 10–30 m. The results demonstrate that the proposed system increases discharge capacity by 20–30% compared to conventional airlift and single-chamber pneumatic systems, while providing continuous operation and improved sediment removal efficiency. The proposed technology provides a practical solution for improving the reliability and sustainability of decentralized rural water supply systems and may also be applied to other engineering processes involving multiphase slurry transport.