24-10-2014, 10:57 AM
Abstracts: Water treatment system requires identifying and fully characterizing the source of the raw water to be treated. The common sources of feed water for water treatment projects include surface waters, well water, and. A complete and representative water analysis should then be made. Environmental considerations include the generation and discharge of waste materials. Each new system should be chosen or designed based on the prevailing water analysis, user preferences and other nontechnical parameters. Absolutely pure water is rarely, if ever, found in nature. The impurities occur in three progressively finer states - suspended, colloidal and dissolved matter. Different methods of treatment are required for their removal or reduction to acceptable limits. The flow through a unit of a drinking water treatment plant is one of the most important parameters in terms of a unit’s effectiveness. In the production of drinking water, screening, plain sedimentation, coagulation and flocculation are almost universally used before filtration, except where water is treated by slow sand filtration. Clarification, which may be by settlement or flotation, is the unit step used immediately before filtration, unless direct filtration is used in cases where the source water is low in turbidity, colour and microorganisms.