Saline water desalination with vapour capture device: a literature review of foundational technologies and underlying principles

Abstract

This review was motivated by the growing need for sustainable water supply technologies in arid lands worldwide. A key driver of this review is to evaluate the potential of presently unused freshwater sources such as from evaporative brine management technologies. In doing so, this paper provides a conceptual building block for innovative water systems in the future with a focus on ecologically, socially and economically sustainable freshwater production. The utilization of solar thermal and wind energy as the principal drivers for brackish and saline water desalination projects provides the link between the technologies and devices that are discussed and evaluated in this review. Of the solar still concepts reviewed, higher productivity rates are achieved with increased optimization of heat and mass transfer processes within the system and productivity is closely linked to the technological complexity of the stills. Water production ranges from 2 to 3 L/m²/day for passive stills up to 100 L/m²/day and more for novel systems with multiple latent heat use. Still–greenhouse systems and seawater greenhouse systems are capable of producing distilled water while providing a vital humid environment for the growth of crops in a greenhouse system. Water production rates of 0.5–2.5 L/m²/day for ‘still in a greenhouse’ systems and up to 55 L/m²/day for seawater greenhouses with improved passive condenser technology can be achieved. Water vapour producing technologies such as wind-aided intensified evaporation, solar dryer technology or the bubble column concept, are assessed for their potential to form part of a novel water desalination scheme.

Keywords:

• vapour capture
• solar still
• seawater greenhouse
• brine management
• bubble column