Desalination is a proces where salt is removed from water in order to get pure water, which is then easily processed into drinking water. Regarding the rapid growth of human population on earth, the need of drinking water is also growing. Climate change also doesn't do as any favour, therefore desalination process could be the key to producing drinking water in the future.
In the introduction there is a short review of some history facts and common usage of desalination in the world. In the main part few desalination processes are presented. In this work three kinds of processes are presented: membrane, thermal and solar processes. With advancing technology, membrane processes are more and more popular, since they are less energy demanding and are already getting more popular than thermal processes. Most widespread process is membrane process – reverse osmosis. Beside reverse osmosis two more processes are presented, each with its unique property and working principle. Those two processes are Electrodialysis and vacuum membrane distillation. Second most common process used in desalination industry are the thermal processes, which are technologically less demanding therefore more used in the past. This process is multistage flash distillation. Multistage flash distillation process has been known for a long time, therefore it is already well studied. In this part of diploma, beside multistage flash distillation process, vapor compression is presented even though it is not a very common process. We live in a world where climate changes and environmental pollution are a big problem, and because desalination processes also need a lot of energy (thermal and/or electrical) to operate (some more than others), part of my work is dedicated to solar energy and processes that convert solar energy to thermal or electrical energy for desalination process purposes. Solar pond is one of them, other are sun collectors and photovoltaic systems.
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