Lime causticization

Additional operations essential to commercial bauxite processing are steam and power generation, heat recovery to minimise energy consumption, process liquor evaporation to maintain a water balance, impurity removal from process liquor streams, classification and washing of ttihydrate, lime caustication of sodium carbonate [497-19-8] to sodium hydroxide [1310-73-2] repair and maintenance of equipment, rehabiUtation of mine and residue disposal sites, and quaUty and process control. Each operation in the process can be carried out in a variety of ways depending upon bauxite properties and optimum economic tradeoffs. 

Polymeric coagulants do not affect pH therefore, the need for supplemental alkalinity, such as lime, caustic, or soda ash, is reduced or eliminated. Polymeric coagulants do not add to the total dissolved soHds concentration, eg, 1 ppm of alum adds 0.45 ppm of sulfate ion (expressed as CaCO ) the reduction ia sulfate can significantly extend the capacity of anion-exchange systems. 

Corrosion—various salts have different acidities (pH of brine can be controlled with lime, caustic soda, or calcium bicarbonate). 

Chemical precipitation is used in porcelain enameling to precipitate dissolved metals and phosphates. Chemical precipitation can be utilized to permit removal of metal ions such as iron, lead, tin, copper, zinc, cadmium, aluminum, mercury, manganese, cobalt, antimony, arsenic, beryllium, molybdenum, and trivalent chromium. Removal efficiency can approach 100% for the reduction of heavy metal ions. Porcelain enameling plants commonly use lime, caustic, and carbonate for chemical precipitation and pH adjustment. Coagulants used in the industry include alum, ferric chloride, ferric sulfate, and polymers.10-12... 

Metallic ions in soluble form are commonly removed from wastewater by conversion to an insoluble form followed by separation processes such as flocculation, sedimentation, and filtration. Chemicals such as lime, caustic soda, sulfides, and ferrous or ferric compounds have been used for metals separation. Polymer is usually added to aid in flocculation and sedimentation. 

For many years since its discovery in 1853 the lime causticization method of manufacturing caustic soda was used, which involves reaction of slaked lime and soda ash. 

This technology involves the addition of chemical reagents to cause insoluble compounds to form. A common method nsed to precipitate metal ions is pH adjustment. The desired pH is one in which the metals exhibit low solubilities in water and therefore precipitate. Common reagents nsed for pH adjnstment include aUcahs such as lime, caustic soda, or magnesium hydroxide slurries to precipitate metal hydroxides. Sulfides such as sodium sulfide or ferrous sulfide slurries are often nsed to precipitate metal snlfides. Other reagents, such as xanthates, can also be nsed to precipitate metal ions. 

In the previous reaction, the number of references is 6. Thus, the equivalent mass of alum is Al2(S04)3 XH2O/6 = 57.05 + 3x and that of the calcium bicarbonate species is 3Ca(HC03)2/6 = 81.05. The other alkalinity sources that can be used are lime, caustic soda, and soda ash. Lime is used in the discussion that follows. Also, alkalinity requirements are usually expressed in terms of CaC03. Therefore, we also express the reactions of alum in terms of calcium carbonate. The respective chemical reactions are ... 

Barium dihydroxide Barium hydroxide Barium hydroxide (Ba(OH)2) Barium hydroxide lime Caustic baryta EINECS 241-234-5 HSDB 1605. Used in glass manufacture, rubber vulcanization, corrosion inhibitors, drilling fluids and lubricants, [monohdratej White powder d = 3.743 slightly soluble in H2O, soluble in acids [octahydratej crystals mp = 78° freely soluble in H2O, MeOH, soluble in EtOH, insoluble in MezCO. 

Cauliflower unsaponifiables. See Cauliflower (Brassica oleracea botyris) oil unsaponifiables Caurite. See Urea-formaldehyde resin Caustic alcohol. See Sodium ethylate Caustic antimony. See Antimony trichloride Caustic baryta. See Barium hydroxide lime Caustic lime. See Calcium hydroxide Caustic potash. See Potassium hydroxide Caustic soda. See Sodium hydroxide Cavamax W6 Pharma, Cavamax W6, Cavamax W7, Cavamax W8. See Cyclodextrin... 

Nutrient correction and pH balancing may be part of pretreatment steps before anaerobic treatment. Nutrient correction may involve dosing with a solution of mainly nitrogen and phosphorus, micro-nutrients or compounds to provide alkalinity. Alkaline compounds (e.g. lime, caustic soda) could also be used for pH correction, dosed in the balancing tank and/or directly inside the reactor whenever the need arises. 

The pH value is a determining factor in many flotation circuits. It is adjusted by using various chemicals such as lime, caustic soda, sulfuric acid, etc. 

Mars red is one of the mars pigments (. v.), developed during the eighteenth century and manufactured by the aqueous precipitation of iron salts (sulfates, chlorides, nitrates and acetates) with an alkali (lime, caustic soda (NaOH), potash, etc.). Mars red was produced by roasting the precipitate produced by this process,... 

Phenol Formaldehyde - 212 100 E E E U sulfuric acid, phosphoric acid. lime, caustic, moderate aeration... 

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