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Lime softening coagulants

Sodium alumiaate is used ia the treatment of iadustrial and municipal water suppHes and the use of sodium alumiaate is approved ia the clarification of drinking water. The FDA approves the use of sodium alumiaate ia steam generation systems where the steam contacts food. One early use of sodium alumiaate was ia lime softening processes, where it iacreases the precipitation of ions contributing to hardness and improves suspended soHds removal from the treated water (17). Sodium alumiaate reacts with siHca to leave very low residual concentrations of siHca ia hot process water softeners. Sodium alumiaate is often used with other chemicals such as alum, ferric salts, clays, and polyelectrolytes, as a coagulant aid (18,19). [Pg.140]

Makeup. Makeup treatment depends extensively on the source water. Some steam systems use municipal water as a source. These systems may require dechlorination followed by reverse osmosis (qv) and ion exchange. Other systems use weUwater. In hard water areas, these systems include softening before further purification. Surface waters may require removal of suspended soHds by sedimentation (qv), coagulation, flocculation, and filtration. Calcium may be reduced by precipitation softening or lime softening. Organic contaminants can be removed by absorption on activated carbon. Details of makeup water treatment may be found in many handbooks (22—24) as well as in technical Hterature from water treatment chemical suppHers. [Pg.363]

Iron Fe+2 (ferrous) Fe+3 (ferric) Discolors water on precipitation source of deposits in water lines, boilers, etc. interferes with dyeing, tanning, paper mfr., etc. Aeration, coagulation and filtration, lime softening, cation exchange, contact filtration, surface active agents for iron retention... [Pg.161]

Some of the available options are powdered activated carbon, UV/o2one, magnetite, lime softening, ion exchange, conventional media filtration, and coagulation with inorganic and polymeric coagulants. [Pg.78]

Ion exchange using packed beds of chloride-form anion-exchange resins Iron(n) coagulation-microfiltration without flocculation and presedimentation Lime softening... [Pg.218]

Aeration coagulation and filtration lime softening cation exchange contact filtration surface-active agents for iron retention... [Pg.89]

Lime is the largest tonnage chemical used in the treatment of potable and industrial water supplies. In conjunction with alum or iron salts it is urod to coagulate suspended solids and remove turbidity. It is also used in water softening to remove lempotaty (bicarbonate) hardness. Typical reactions ate ... [Pg.120]

Precipitation and dissolution phenomena are extremely important in both natural waters and water treatment processes. Dissolution of minerals is a prime factor in determining the chemical composition of natural waters. Natural water chemical composition can be altered by precipitation of minerals and the subsequent sedimentation of these solids from supersaturated solutions. Water and wastewater treatment processes such as lime-soda softening, iron removal, coagulation with hydrolyzing metal salts, and phosphate precipitation are based on precipitation phenomena. [Pg.243]

See other pages where Lime softening coagulants is mentioned: [Pg.299]    [Pg.299]    [Pg.146]    [Pg.149]    [Pg.132]    [Pg.59]    [Pg.314]    [Pg.80]    [Pg.87]    [Pg.92]    [Pg.238]    [Pg.1179]    [Pg.333]    [Pg.345]    [Pg.50]    [Pg.164]    [Pg.178]    [Pg.11]    [Pg.643]    [Pg.499]    [Pg.755]    [Pg.269]    [Pg.311]    [Pg.1723]    [Pg.867]    [Pg.364]    [Pg.509]    [Pg.2083]    [Pg.2010]    [Pg.269]    [Pg.169]    [Pg.75]    [Pg.1998]    [Pg.316]    [Pg.136]    [Pg.155]    [Pg.1019]   
See also in sourсe #XX -- [ Pg.92 ]



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Lime (coagulant

Lime softening

Lime softening softener

Liming

SOFTEN

Softens

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