Phosphorus removal in low alkalinity secondary effluent using alum

Article

Abstract

The alkalinity plays an important role in phosphorus removal using coagulant. The dosage of coagulant in the low alkalinity wastewater is limited due to rapid pH changes. In the present study, a series of jar test was conducted using low alkalinity wastewater (50 mg/L) to evaluate the optimum pH, dosage and performance parameters (slow mixing and settling time) for the common coagulant alum. From the experiment, it was found that the dosage of coagulant and removal of phosphorus depend upon the pH of the wastewater after adding coagulant. The final optimum pH for efficient P removal was found to be within the range of 5.7–5.9. This range acts as an indicator and it is the maximum tolerable pH range for phosphorus removal for low alkalinity wastewater. The optimum time for slow mix and settling was found to be 20 min. The optimum mole ratio of alum to remove one mole of phosphorous was found to be 2.3. The alum coagulation at pH 7 produced effluent with the total residual phosphorus and reactive phosphorus content of 0.3 and 0.9 mg/L, respectively.

Keywords

Alum phosphorous coagulation pH secondary effluent 

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References

  1. Ahmad, A. L.; Sumathi, S.; Hameed, B. H., (2006). Coagulation of residue oil and suspended solid in palm oil mill effluent by chitosan, alum and PAC. Chem. Eng. J., 118, 99–105.CrossRefGoogle Scholar
  2. APHA (2005). Standard Methods for the Examination of Water and Wastewater., 21st. Ed., American Public Health Association, American Water Works Association, Water Pollution and Control Federation, Washington, DC.Google Scholar
  3. Clark, T.; Stephenson, T.; Pearce, P. A., (1997). Phosphorus removal by chemical precipitation in a biological aerated filter. Water Res., 31(10), 2557–63.CrossRefGoogle Scholar
  4. De Hass, D. W.; Wentzel, M. C.; Ekama, G. A., (2000). The use of simultaneous chemical precipitation in modified activated sludge systems exhibiting biological excess phosphate removal Part 1: Literature review. Water SA., 26(4), 439–452.Google Scholar
  5. Georgantas, D. A.; Grigoropoulou, H. P., (2006). Phosphorus and organic matter removal from synthetic waster using alum and aluminum hydroxide. Global NEST J., 8(2), 121–130.Google Scholar
  6. James, M.; Ebeling Sibrell, P. L.; Ogden, S. R.; Steven, S. T., (2003). Evaluation of chemical coagulation-flocculation aids for the removal of suspended solids and phosphorus from intensive recirculating aquaculture effluent discharge. Aquacult. Eng., 29, 23–42.CrossRefGoogle Scholar
  7. Lee, S. I.; Weon, S. Y.; Lee, C. W.; Koopman, B., (2003). Removal of nitrogen and phosphate from wastewater by addition of bittern. Chemosphere, 51, 265–271.CrossRefGoogle Scholar
  8. Lujubinko, L.; Julianna, G.; Mirjana, D.; Tatjana, K., (2004). Optimization of pH value and aluminium sulphate quantity in the chemical treatment of molasses. Eur. Food Res. Tech., 220, 70–73.Google Scholar
  9. Mahmut, O.; Ayhan, S., (2003). Effect of tannins on phosphate removal using alum. Turkish J. Eng. Environ. Sci., 27, 227–236.Google Scholar
  10. Mervat, E.; Logan, A. W., (1996). Removal of phosphorus from secondary effluent by a matrix filter. Desalination, 106, 247–253.Google Scholar
  11. Metcalf and Eddy, (1993). Wastewater engineering treatment disposal and reuse. McGraw-Hill, USA.Google Scholar
  12. Muller, J. A.; Palonen, H., (2002). Optimisation of floc stability by mechanical pre and post stressing. IWA publishing, UK., 7, 297–308.Google Scholar
  13. Paul, E.; Laval, M., L.; Sperandio, M., (2001). Excess sludge production and cost due to phosphorus removal. Environ. Tech., 22, 1363–1371.CrossRefGoogle Scholar
  14. Pinotti, A.; Zaritzky, N., (2001). Effect of aluminum sulfate and cationic polyelectrolytes on the destabilization of emulsified wastes., Waste Manage. 21(6), 535–542.CrossRefGoogle Scholar
  15. Plaza, E.; Levlin, E.; Hultman, B., (1997). Phosphorus removal from wastewater-a literature review. Division of Water Resources Engineering, Department of Civil and Environmental Engineering, Royal Institute of Technology, Stockholm.Google Scholar
  16. Robert, J.; Takashi, S.; Motoharu, M., (2003). The microbiology of biological phosphorus removal in activated sludge systems. Microbiol. Rev., 27, 99–127.Google Scholar
  17. Sedlak, R., (1991). Phosphorus and nitrogen removal from muuicipal wastewater: Principles and practice. Lewis publishers, USA.Google Scholar
  18. Stanley, E. M., (2001). Fundamentals of environmental chemistry. CRC Press, London.Google Scholar
  19. Vernon, L. S.; David, J., (1980). Water chemistry. John Wiley and Sons, USA.Google Scholar
  20. Wang, X. J.; Xia, S. Q.; Chen, L.; Zhao, J. F.; Renault, N. J.; Chovelon, J. M., (2006). Nutrients removal from municipal wastewater by chemical precipitation in a moving bed biofilm reactor. Proc. Biochem., 41, 824–828.CrossRefGoogle Scholar
  21. Wang, Y.; Han, T.; Xu Bao, G.; Tan, Z., (2005). Optimization of phosphorus removal from secondary effluent using simplex method in Tianjin, China. J. Hazard. Mater., 21, 183–186.CrossRefGoogle Scholar
  22. Xie, W.; Qunhui, W.; Hongzhi, M.; Yukihide, O.; Hiroaki, I. O., (2005). Study on phosphorus removal using a coagulation system. Proc. Biochem., 40, 2623–2627.CrossRefGoogle Scholar
  23. Yeoman, S.; Stephenson, T.; Lester, J. N.; Perry, R., (1988). The removal of phosphorus during wastewater treatment: a review. Environ. Pollut., 49, 183–233.CrossRefGoogle Scholar

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© Islamic Azad University 2008

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringSungkyunkwan UniversitySuwon-SiKorea

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