Advances in sustainable adsorption desalination configuration, materials, and challenges: A state-of-the-art review

Abstract

Adsorption desalination (AD) is a promising, low-cost technology that addresses the limitations of traditional desalination methods by porous materials. AD utilizes renewable energy such as solar and industrial low-grade waste heat, as the heat source. This makes AD a promising pollution-free and environmentally friendly technology. A notable innovation in this field is the Adsorption Cooling Cum Desalination System (ACDS), which offers a novel approach for the simultaneous production of high-quality potable water and cooling energy, using low-grade heat sources in the range of 50–95 °C. This dual-purpose system is particularly advantageous in areas where water scarcity and high temperatures co-exist, as it maximizes the efficient use of energy and resources.

This review aims to provide a comprehensive overview of the ADS/ACDS cycle, focusing on the simultaneous production of pure water and cooling using sustainable, low-grade energy sources. Despite its promising potential, the current efficiency of AD systems is still low, making them far from market-ready for widespread use. However, hybridizing AD with low-grade renewable energy systems (RES), such as solar or industrial waste heat, could significantly improve the efficiency of the desalination process.

The review further examines the configurations, design criteria, and operational parameters of AD systems, compiling the results of various research studies conducted to date. Additionally, the integration of AD with other desalination technologies, particularly MED, HDH, and RO, is explored as a means to enhance the overall performance of desalination systems. The performance of conventional AD systems is discussed in terms of specific daily water production (SDWP), which typically reaches 4.7 m³/tonne/day, and specific energy consumption (SEC), which is approximately 1.5 kW h/m³. A merged condenser-evaporator configuration improves SDWP by 69 %, with the added benefit of zero SEC at evaporator temperatures ranging from 30 °C to 42 °C. Solar-driven ACD systems have shown promising results, with a specific cooling power (SCP) of 112 W/kg and a coefficient of performance (COP) of 0.45. However, the operational challenges associated with these systems present significant barriers that hinder their commercialization.

This review seeks to address these challenges by guiding researchers and industry practitioners toward understanding the fundamental concepts of AD, identifying operational issues, and proposing practical solutions to advance the technology.