System modelling of energy-efficient water treatment unit for space applications.

This thesis centers on the development of water recovery systems (WRS) tailored for sustainable, long-duration space missions akin to those on the International Space Station (ISS). The main goal is to elevate system efficiency, reliability, and overall performance of water recovery system, with a focus on reducing dependence on Earth's resources. This effort is geared toward ensuring astronaut safety and strengthening the long-term sustainability of missions. Investigating the historical evolution and milestones of water recovery systems, the study meticulously examines the current ISS water treatment system, encompassing intricate components like the Low-Pressure Distiller, Condenser/Economizer, Electrical Heater, Reverse Osmosis Module, Resin Filter, and Activated Carbon Filter. Also, in the present work we propose alternative technologies and identifies essential parameters and equations, emphasizing energy management and water treatment system. We have employed the lumped parameter modeling to design and develop the water treatment system and the results were validated experimentally. The current research compares three distinct water system layouts—the present ISS setup, an energy-conserving configuration integrating heat storage, and an alternative design using membrane distillation. We evaluated their efficiency in producing high-quality water, minimizing energy consumption, and maximizing water recovery. This study is aimed to elevate the quality of water quality and energy efficiency for safer, self-sustaining space exploration endeavors.