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for up to half of a plant’s production cost. In South Africa, we do not have a constant or consistent energy supply available to see this process as a final solution. Membrane technology makes use of semi-permeable membranes to separate salts from water. In the Cape Town area, the emergency desalination plants used reverse osmosis, which uses high pressure and a semi-permeable membrane to filter salt and other impurities from water. In reverse osmosis, water from the ocean is forced through thousands of tightly wrapped, semi-permeable membranes under extremely high pressure. The membranes allow the smaller water molecules to pass through, leaving salt and other impurities behind. Desalination processes are still developing and there are a number of other technologies available as alternative solutions. One of them would be so-called multiple effect distillation (MED) which uses heat and electricity to produce
A complex process Desalination, in any form, is based on simple principles but highly complicated in practice. It is the process of removing salt and other impurities from seawater to make it drinkable. The two most common methods for desalination are thermal and membrane technologies. The thermal technology involves heating saline water (seawater) to produce water vapour, which is then condensed and collected as fresh water. This process is called distillation, which involves boiling seawater in a still, collecting steam, and condensing it to obtain fresh water. Distillation is the most obvious method for removing salt, but it consumes large amounts of energy whcih can account
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Issue 1 – 2024
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