Environmental assessment of sustainable energy options for multi-effect distillation of brackish water in isolated communities

• Published in: Journal of cleaner production Vol. 213; pp. 1371 - 1379
• Main Authors: Tarpani, Raphael Ricardo Zepon, Miralles-Cuevas, Sara, Gallego-Schmid, Alejandro, Cabrera-Reina, Alejandro, Cornejo-Ponce, Lorena
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10-03-2019
• Subjects: Arsenic; Boron; Desalination; Life cycle assessment (LCA); Solar and biomass energy; Water treatment; Water treatment; Life cycle assessment (LCA); Boron; Solar and biomass energy; Arsenic; Desalination
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2018.12.261

Access to sufficient quantities of fresh water is becoming increasingly difficult, especially in dry regions. Moreover, high levels of salinity, arsenic and boron are further limiting the access to quality fresh water in many isolated communities worldwide. This paper evaluates the life cycle environmental impacts of a small multi-effect distillation (MED) plant, treating brackish water with high levels of these metalloids in an isolated location in Northern Chile. The facility currently operates solely with electricity from a diesel generator and heat from a biomass boiler. In order to evaluate the environmental impacts of more sustainable energy options, the implications of the use of solar fields and grid electricity as potential alternatives have been analysed. The results demonstrate that coupling solar fields and grid electricity is the best option, sharply decreasing impact in most categories in comparison to the current operating mode of the plant. This was attributed to the impact savings from reducing/eliminating onsite diesel and biomass combustion, and their associated transportation to the plant. For MED desalination in off-the-grid areas, the use of solar energy is highly recommended as an alternative to complement the use of diesel and biomass, especially if the latter is not nearby the unit. The concentration of arsenic and boron was reduced to below the required standards for irrigation and livestock consumption. The article concludes that the use of solar energy and grid electricity are environmentally beneficial for the production of quality fresh water from brackish water using MED at isolated communities.
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•First LCA of a multi-effect distillation plant for isolated communities.•Diesel generator, biomass burning and transport are main environmental hotspots.•Simultaneous use of solar, biomass and grid electricity are the best alternative.•Solar energy is good complement to diesel and biomass operation in off-the-grid areas.•High (99%) removal of arsenic and boron in the final distillate was observed.