Desalination at low temperatures and low pressures

• Published in: Desalination Vol. 244; no. 1; pp. 239 - 247
• Main Authors: Gude, Veera Gnaneswar, Nirmalakhandan, Nagamany
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.08.2009; Elsevier
• Subjects: Applied sciences; Barometric pressure; Desalination; Drinking water and swimming-pool water. Desalination; Evaporation; Exact sciences and technology; Feasibility; Low pressure; Low pressure desalination; Low temperature; Pollution; Process heat; Prototype scale demonstration; Saline water; Solar collectors; Utilization of waste heat; Wastes; Water treatment and pollution; Prototype scale demonstration; Low pressure desalination; Utilization of waste heat; Low temperature; Solar collector; Phase change; Desalination; Production; Evaporation
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2008.06.005

A low-temperature phase-change desalination process configuration is presented in this study. This configuration enables saline water to be evaporated at near-ambient temperatures under near-vacuum level pressures created by the barometric head without any mechanical energy input. Thermodynamic advantages and benefits of lowtemperature phase-change desalination are discussed and results from a prototype test system are presented to demonstrate the feasibility of the proposed configuration. Results of this study show that a freshwater production rate of 0.25 kg/h (6 L/d) can be sustained at evaporation temperatures as low as 40ºC. These results suggest that this process has the potential to be driven by low-grade heat sources such as waste process heat or solar collectors at temperatures as low as 50ºC.