Phosphorus removal

Handbook of Membrane Separations Chemical, Pharmaceutical, Food and Biotechnological Applications 

Although EBPR and denitrification can have adverse effects on each other, as nitrate in the anaerobic zone allows hetero-trophic bacteria to oxidize the carbon compounds instead of producing VFA, there are some denitrifying PAOs (DPAO), which can utilize nitrates under anoxic conditions to assimilate phosphate. DPAO s growth rate is lower than PAOs under aerobic conditions. Monclus et al. [29] achieved phosphate removal rates of 13.6 mg P g VSS h for PAO and 5.6 mg P g- VSS h-i for the DPAO. 

Micropollutant-degrading bacteria generally have a low specific growth rate, and therefore, the extended SRT in MBRs should favor the enrichment and growth of specialist bacteria with the ability to assimilate and mineralize specific pollutants. However, when making comparisons between processes, consideration must be given to the possibility that improved removal rates from the MBR may arise from the retention of such pollutants by adsorption on biomass particles rather than by improved biodegradation. 

The precipitated hydroxyapatite or other form of calcium phosphate is incorporated in the sludge floe. 

Chemically, 90-95% phosphate removal is accomplished by precipitation with lime as shown by the following reaction  

Salts of Al, Fe and Mg are also capable of forming precipitates with phosphate. Phosphate can be removed from solution by adsorption on some solids, particularly activated alumina, AI2O3. Removals of up to 99.9% of orthophosphate have been achieved with this method. 

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Phosphorus Removal. Phosphoms can be removed from wastewater either chemically or biologically. 

Aluminum based chemicals have been used for many years in wastewater treatment applications for suspended solids removal. These include dry and liquid alum, with sodium aluminate used in activated sludge plants for phosphorus removal. 

B) Preparation of o- 2-Thienyl-(2 )-Ethyl]Benzoic Acid 24.0 g of thenylidene-(2)-phthalide, 8.8 g of red pulverized phosphorus, 240 ml of hydrochloric acid (d = 1.7) and 240 ml of glacial acetic acid are heated to boiling under nitrogen and while stirring vigorously. 70 ml toluen are then added and 6.0 g of red phosphorus added in small portions over a period of 1 hour. It is then poured into 3 liters of ice water, stirred with 300 ml of chloroform and the phosphorus removed by filtration. 

Modified ASM2d model including pH effect on enhanced biological phosphorus removal... 

The dissolved inorganic pollutants for the coil coating category are hexavalent chromium, chromium (total), copper, lead, nickel, zinc, cadmium, iron, and phosphorus. Removal of these inorganics is often... 

Sanchez, M., Mosquera-Corral, A., Mendez, R., and Lema, J.M., Effect of ammonia on the performance of denitrifying reactors, European Conference on New Advances in Biological Nitrogen and Phosphorus Removal for Municipal or Industrial Wastewaters, Narbonne, France, pp. 119-126, 1998. 

Xie B, Wang L, Liu H (2008) Using low intensity ultrasound to improve the efficiency of biological phosphorus removal. Ultrason Sonochem 15 775-781... 

Dabert P, Fleurat-Lessard A, Mounier E et al (2001) Monitoring of the microbial community of a sequencing batch reactor bioaugmented to improve its phosphorus removal capabilities. Wat Sci Technol 43 1-3... 

The first step in solving this problem is to write down a series of equations, one for each reservoir, that expresses the balance between the phosphorus supplied to each reservoir (the source) and the phosphorus removed from each reservoir (the sink). Corresponding to each of the arrows in Figure 3-1 is a flux of phosphorus equal to the water flux multiplied by the concentration of phosphorus in the reservoir from which the water is flowing. Let sat be the concentration of phosphate in the surface Atlantic, sind in the surface Indo-Pacific, dind in the deep Indo-Pacific, ant in the Antarctic, and dat in the deep Atlantic. Express all concentrations in units of 10 3 mole P/m3. 

Bowker, R. P. G. and Stensel, H. D., Phosphorus Removal from Wastewater, Noyes Data, Park Ridge, NJ, 1990,21. 

Preservation of readily biodegradable substrates in sewers may be crucial in case of denitrification and phosphorus removal in advanced treatment processes. 

The results in Figure 6.9 show that the production rate of readily biodegradable substrate (Ss) by the anaerobic hydrolysis is larger than the removal rate. It is a major result that readily biodegradable substrate is not just preserved but produced. This fact has positive implications on the subsequent treatment processes in terms of denitrification and biological phosphorus removal. On the other hand, it is negative if wastewater treatment is only required in terms of BOD removal. 

Biological phosphorus removal, as advanced wastewater treatment, 25 907... 

Phosphorus production technology, 79 5 Phosphorus production plants, 79 17 Phosphorus removal, as advanced wastewater treatment, 25 907 Phosphorus-rich phosphides, 79 59 Phosphorus selenides, 22 87 Phosphorus sesquisulfide, 79 47 Phosphorus-silver, UNS designation,... 

According to the German Association for the Water Environment, ATV (Teichgraber B., 1998 and Teichgraber et al. 2001) to calculate tP from the whole cycle to biological phosphorus removal phase tBio-p should be taking away. 

Goronszy, M.C., Rigel, D. Simplified biological phosphorus removal in a fed-batch reactor without anoxic mixing sequences. J. W P C F 63 (3), 1991, 248-258. 

Buchan [92] has carried out a study using electron microscopy combined with energy dispersive X-ray analysis, to determine the location and nature of the stored phosphorus in activated sludge samples from seven different treatment plants in South Africa, which all show enhanced phosphorus removal. The results indicate that there is a biological mechanism of enhanced phosphorus uptake in activated sludge. 

The experimental aspects of this study were focussed on two hard-water lakes in Switzerland, namely, the northern basin of Lake Zurich and Lake Sempach. The hydraulic residence time of Lake Zurich is 1.2 years. Most of the particles in the lake are produced directly or indirectly by biological processes within the lake itself (e.g., photosynthesis, CaC03 precipitation). Phosphorus removal has been implemented in recent years at all wastewater treatment plants discharging into the lake at present Lake Zurich can be described as between meso- and eutrophic. Lake Sempach has an average hydraulic residence time of 15.8 years as in Lake Zurich, particles in the lake waters are primarily autochthonous. Phosphorus concentrations have increased substantially and the lake is eutrophic. 

Fluoride and Phosphorus Removal from a Fertilizer Compiex Wastewater... 

Improvement and Phosphorus Removal in Wetlands and Sand Filters... 

USEPA. Process Design Manual for Phosphorus Removal Office of Technology Transfer, U.S. Environmental Protection Agency Washington, DC, 1971. 

Akin, B.S. Ugurlu, A. Enhanced phosphorus removal by glucose fed sequencing batch reactor. J. Environ.. Sci. and Health 2001, A 36 (9), p 1757. 

Wang, L.K. An Emerging Technology for Phosphorus Removal from Wastewaters, Technical Report LIWT/1-2002/253 Lenox Institute of Water Technology Lenox, MA, 2002, 18 p. 

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