Degree Name

Doctor of Philosophy


School of Civil, Mining and Environmental Engineering


Sustained water scarcity conditions due to increased fresh water demand necessitates water authorities to consider alternatives for supplementary water supply. Water recycling in a sustainable manner is increasingly being practiced around the world for protection of water resources. Abundantly available brackish water sources with suitable treatment can be used for recycling purposes. On the other hand, grey water recycling has been accepted due to the quantity and quality of this source compared to sewage. A typical household’s grey water contains approximately 70% of the domestic wastewater and its TDS, COD and TOC concentrations are 49.7, 39.7 and 38.3% less than medium sewage. Grey water treatment for reuse will not only decrease the rate of fresh water consumption in urban areas but also will reduce the pressure on wastewater treatment plants. These substantial improvements are obtainable by means of an appropriate treatment technology in a sustainable and efficient manner. Water is also closely interconnected with energy. Water extraction, treatment, transport and distribution all requires energy. In regard with the exigent situations predicted for water and energy in future as well as their interactions, the potential of solar powered treatment technologies are investigated as an attractive and promising solutions.

This research compared three innovative solar-based treatment systems from a selection of a broad range of technologies that have been used for brackish and grey water treatment. The treatment systems were assessed through a multi-criteria decision analysis method embedding twelve sustainability indicators under three major criteria. Pairwise comparison of indicators and selected systems revealed that the solar powered vacuum membrane distillation (SVMD) system was the most sustainable technology option for both brackish and grey water treatment based on economic, environmental and social pillars.