Precipitation In Precipitation

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Removal process in a precipitation process dominates, while some small role Coagulation and adsorption play. Transform phosphorus ions into Solid place in three stages. According to Shen and Morgan (1988) and Stam and Morgan (1970), these stages include: • solid material to form the core • Storage precipitated crystals and begin to grow • Crystal mature As used herein orthophosphate, paragraph 2 is the most common Groups phosphorus compounds and theoretical papers focused on these Reagent 4. Trivalent metal salts for phosphorus removal of urban sewage. The most common are: ♦ aluminum sulfate, ♦ ferric chloride, ♦ ferrous(bivalent) and ferric sulfates. Lime is one of the main chemicals used in previous phosphorus (EPA1976), now only played a minor role. The reason for this change is significant Maintenance and operation of lime to increase the quality of sludge, and issues Processing and consumption facilities (Hruschka1980). Precipitation mentioned above: Iron (Ⅲ), Fe (Ⅱ), aluminum (III) and the presence of salt in the form of Ca Orthophosphate solution precipitates. The following formula Precipitation (Alvin 1983, 1989) of the reaction: Aluminum ions from the reaction of phosphate ions, such as: Al 3+ + PO 3- → AlPO4 ↓ so the weight ratio of the reaction is 0.87 : 1 of Al to P. The reaction of ferric ions can be illustrated by: Fe3+ + PO 43- → FePO4 The weight ratio of the stoichiometric reaction is 1.8:1. No sediment content-specific chemical structure. Typically, a simplified The aluminum phosphate FePO4 or form is used in the paper. Summary (Sedlak empirical 1991) allows the actual content of the simplified formula differs from these assumptions And the following empirical formula is proposed: Mer * ... ... middle of paper ... ...ose proposed iron. One hypothesis is That is the only phosphate compounds, aluminum phosphate precipitated. According to these Equation phosphate8 minimum aluminum solubility at pH 5.5 to achieve. Stoichiometric ratio Al: P ratio of 1:1 (molar). In real terms the value of the necessary calculations alum dose varies. Alum dosage may be necessary due to the increase of the calculated value is compared The following factors: + According to Jenkins et al (1971) with some additional aluminum ions react Phosphate ion, hydroxyl ion to react with the other. Therefore, it is Number of Al salt needs to be added specific molar ratio of aluminum big: P = 1:1. This ratio is the real author of the minimum (5 to 3): 1. + Alum in terms of functionality but also react with other components of wastewater Solidification and services exist in trace and colloidal Wastewater,
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