World today is facing an acute shortage of energy. Large amount of energy generated from different mechanical processes is dumped into the environment as a waste heat. This heat can be utilized for purification of water. Several researchers had worked in the area of desalination of water using waste heat from different mechanical systems. Many low cost water purifications techniques have been developed by the researchers in the past. The aim of this work is to review different methods/techniques developed for purification of water. The reviewed low cost methods will reduce the usage of excess energy in different water purification techniques like reverse osmosis, deionization etc. In future, renewable or waste energy based water purification systems can be developed. Moreover, the designing of systems based upon distillation for purification of water can solve water related issues in the 'Malwa' belt of Punjab where the content of heavy metals and uranium was found to be quite high.

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Distillation Energy Waste Heat Water Purification