Comparison of environmental impact and energy efficiency of desalination processes by LCA

Abstract

In this study two desalination technologies have been compared by means of LCA with the focus on energy supply with a variety of scenarios based on different assumptions. The studied technologies are reverse osmosis and the newly developed technology Memstill where electrical energy demand is reduced by using external thermal energy source and use of chemicals is reduced. The scenarios are chosen to simulate different locations of sea water desalination plants and to demonstrate the impact of energy demand and energy source, chemical use and longer components' life times on the environment. The results show the dominant impact of energy demand on the overall results for all applied environmental impact assessment methods; transports, material and even chemical use are of negligible impact on the total score. The use of waste heat in case of Memstill offers a great opportunity to reduce the negative environmental impacts related to energy use. As the LCA analysis tool the GaBi software has been applied with the Ecoindicator99, CML 2001 and Ecopoints environmental impact assessment methods.

Carbon footprint assessment of Western Australian Groundwater Recycling Scheme

“…In another study, desalination technologies were compared with Memstill that involves the use of an external thermal energy resource to reduce chemical requirements. It was identified that due to the lower energy requirement of the Memstill unit it had a lower environmental impact than a similar sized reverse osmosis unit (Tarnacki et al 2011).…”

Environmental Impacts of Reverse Osmosis in Wastewater Treatment Versus Desalination to Mend the Water Cycle: A Life Cycle Assessment

“…For instance, Raluy et al [36] found that the construction phase only contributed 5% to the total environmental impact. Furthermore, brine disposal was also excluded from the study due to its relatively negligible environmental impact [34], [36].…”

Environmental sustainability assessment of seawater reverse osmosis brine valorization by means of electrodialysis with bipolar membranes

“…Hereafter, we use Carbon Footprint (CF) as reference for the burdens related to CC. Moreover, energy consumption has been previously reported as the desalination main environmental issue (Vince et al 2008;Lyons et al 2009;Meneses et al 2010;Tarnacki et al 2011Tarnacki et al , 2012Al-Sarkal and Arafat 2013). In this way, the CF of each treated cubic meter of seawater treated can be assessed.…”