Water Supply, Waste ,Water, treatment

Water Supply

Water Supply: Lime is used in treatments of potable and industrial water supplies. It is used by many municipalities to improve their water quality, especially for softening water and removing arsenic. Indeed, lime is definitely used for drinking water treatment.

Softening: In water softening, hydrated lime is used to remove carbonate hardness from the water. Hardness caused by other calcium and magnesium salts, called non-carbonate hardness, is generally treated by means of lime-soda process, which entails the precipitation of magnesium by lime. Co-produced calcium salt reacts with soda ash to form calcium carbonate precipitate. Lime-enhanced softening can also be used to remove arsenic from water. Recent changes to the national drinking water standard for arsenic have heightened the need for this kind of treatment.

pH Adjustment/Coagulation: Hydrated lime is widely used to adjust the pH of water to prepare it for further treatment. Lime is also used to combat "red water" by neutralizing the acidic water, thereby curtailing corrosion to pipes and mains. Corrosive water also contains an excessive amount of carbon dioxide. Lime precipitates the carbon dioxide, forming calcium carbonate protective coating on the inside of water mains.

Lime is used in conjunction with alum or iron salts for coagulating suspended solid content, clearing up the turbidity of "raw" water. It serves to maintain the proper pH for best coagulation condition. In some water treatment plants, alum sludge is treated with lime to facilitate sludge thickening on pressure filters.

Effect on Pathogen Growth: By raising the pH of water to 10.5-11 through the addition of lime and retaining the water in contact with lime for 24-72 hours, the water is no longer a viable environment for growths of bacteria and certain viruses. This application of lime is utilized where "phenolic water" is a problem because chlorine treatment tends to produce unpalatable water due to the presence of phenols. This process, called "excess alkalinity treatment," also removes most heavy metals./p>

Removal of Impurities: One of the most common methods for removing silica from water is the use of dolomitic lime. The magnesium component of lime is the active constituent in silica removal. Lime is also used to remove manganese, fluoride, organic tannins and iron from water supply.

Quick Lime Powder and Hydrated Lime from Golden Lime (Sutha) have been successfully fulfilling the need of Steel industry for over 10years.

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