Phosphorous removal

Phosphorous removal is most commonly done by chemical precipitation with iron or aluminum compounds, such as ferric chloride or alum (aluminum sulfate). The solids which are produced can be settled along with other sludges, depending on where in the treatment train the process takes place. "Lime", or... 

Phosphorus is removed in wastewater treatment plants by chemical means (e.g., phosphorus precipitation with iron or aluminum see Section 10.1.2) and by microbiological means known as biological phosphorous removal. The principal advantages of biological phosphorus removal include reduced chemical costs and a smaller sludge production as compared to chemical precipitation. It is based on the following facts ... 

Cornwell, D.A. and Zoltec, J. Recycling of alum used for phosphorous removal in domestic wastewater treatment. J. WPCF, 49, 600-612, 1977. 

Cellulose acetate (CA) is still considered the preeminent membrane for wastewater treatment because it is capable of producing the highest flux per unit surface area at specified levels of solute rejection. The rejection performance of RO using a 90% sodium chloride rejection CA membrane was studied. Phosphorous removal was greater than 95% in all cases. Ammonia removals were generally in excess of 90%, and nitrite and nitrate removals generally ranged from 84% to 97% (32). 

Phosphorous can exist as H PO (i = 0, 1, 2, and 3) at different pH values. As shown in the above equation, solution pH will decrease with the release of hydrogen ions. According to the pC-pH diagram illustrated in Fig. 5, the formation of H PO and HPO contributes to the uptake of phosphorous at pH 1 to 5 and 5 to 10, respectively. The pH dependency of phosphorous removal indicates that the amount of HPO4 is higher than that of H2PO4 as shown in Fig. 6. 

McMahon, K.D. Jenkins, D. Keasling, J.D. Polyphosphate kinase genes from activated sludge carrying out enhanced biological phosphorous removal. Water Sci. Technol. 2002, 46 (1-2), 155-162. 

This Is a compilation of articles and papers from WEFJournals and conferences. Treatment processes covered are disinfection, nutrient and phosphorous removal, RBCs, activated sludge, and digesters. 

Sulfur removal is a partition process and is favoured by high basicity, a high FeO level in the slag, a large volume of slag and high temperatures. Typically 40 % of the sulfur in the hot metal is removed in the BOS vessel. Phosphorous removal is favoured by lower temperatures otherwise the optimum conditions are similar to those for sulfur. 

DeBusk, T. A., K. A. Grace, F. E. Dierberg, S. D. Jackson, M. J. Chimney, and B. Gu. 2004. An investigation of the limits of phosphorous removal in wetlands amesocosm study of a shallow periphyton-dominated treatment system. Ecol. Eng. 23 1-14. 

Phosphoric Removal of calcium Horizontal pan filter Up to 6 100 Crystalline/ 1,9 Resists abrasion and blinding... 

---