The process of removing contaminants from water is generally referred to as water purification or water treatment. There are several methods used to achieve this, including:
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Filtration: This involves passing water through physical barriers, such as sand, gravel, or membranes, to remove solids and some microorganisms.
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Coagulation and Flocculation: Chemicals (coagulants) are added to water to bind with contaminants, forming larger particles (flocs) that can be easily removed by sedimentation or filtration.
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Sedimentation: After coagulation and flocculation, the water is allowed to sit so that the larger particles can settle to the bottom.
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Disinfection: This process involves killing or inactivating pathogens in the water using chlorine, ozone, ultraviolet (UV) light, or other disinfectants.
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Reverse Osmosis: This method uses a semi-permeable membrane to remove a wide range of contaminants from water, including dissolved solids, salts, and microorganisms.
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Activated Carbon Adsorption: This method uses activated carbon to adsorb organic chemicals and some heavy metals, improving taste and odor.
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Ion Exchange: This technique is used to remove specific ions from water, such as heavy metals or hardness ions (calcium and magnesium), by exchanging them with less harmful ions.
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Biological Treatment: In some cases, biological processes using microorganisms are employed to break down organic contaminants.
These methods can be used individually or in combination, depending on the source of the water and the specific contaminants present.