Desalination turns seawater into drinking water primarily by removing salt and other minerals, often using a process called reverse osmosis.
Here's a breakdown of the process:
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Intake: Seawater is drawn into the desalination plant.
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Pre-treatment: The seawater undergoes filtration to remove larger particles, algae, and debris. This step is crucial to protect the delicate reverse osmosis membranes.
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Reverse Osmosis (RO):
- The pre-treated seawater is forced under high pressure through a semi-permeable membrane.
- This membrane allows water molecules to pass through while blocking salt, minerals, and other impurities.
- The result is two streams: permeate (desalinated water) and concentrate (brine - a highly concentrated salt solution).
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Post-treatment: The desalinated water is stabilized and disinfected to meet drinking water standards. This may involve adding minerals for taste and alkalinity control, as well as disinfection with chlorine or other methods.
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Brine Disposal: The concentrated brine is typically discharged back into the ocean, carefully managed to minimize environmental impact. Methods include dilution and diffusion to reduce salinity spikes.
In essence, desalination mimics the natural process of osmosis but reverses the flow by applying pressure to separate water from salt. This ensures a safe and reliable source of fresh drinking water, especially in regions facing water scarcity.
