[1. Morse, G.K., Lester, J.N. & Perry, R. (1993). The economicand environmental impact of phosphorus removal from wastewaterin the European Community. Selpher Publications, London.]Search in Google Scholar
[2. Jasinski, S.M. (2010). U.S. Geological Survey, MineralCommodity Summaries, chapter Phosphate Rock. United States Government Printing Offi ce, Washington.]Search in Google Scholar
[3. Schröder, J.J., Cordell, D., Smit, A.L. & Rosemarin, A. (2009). Sustainable use of phosphorus, European Union tenderproject ENV.B.1/ETU/2009/0025. Report 357. Plant Research International, Wageningen University and Research Centre, Wageningen, The Netherlands. Retrieved March 23, 2011, from: http://ec.europa.eu/environment/natres/phosphorus.htm.]Search in Google Scholar
[4. Steen, I. (1998). Phosphorus availability in the 21st century: Management of a non-renewable resources. Phosphorus andPotassium, 217, 25-31.]Search in Google Scholar
[5. Schröder, J.J., Smit, A.L., Cordell, D. & Rosemarin, A. (2011). Improved phosphorus use effi ciency in agriculture: A key requirement for its sustainable use. Chemosphere, 84, 822-831. DOI:10.1016/j.chemosphere.2011.01.065.10.1016/j.chemosphere.2011.01.065]Search in Google Scholar
[6. Smith, V. (1999). Eutrophication: impacts of excess nutrients of freshwater, marine and terrestrial ecosystems. Environ.Pollut., 100, 179-196.10.1016/S0269-7491(99)00091-3]Search in Google Scholar
[7. Andersen, A. (2003). Disposal and recycling routes for sewage sludge- report for the UE Commission - DG - Environment - B/2, SEDES. CEEP Scope Newsl., 50, 2-3. Retrieved 12 September, 2010, from: http://www.ceep-phosphates.org/Files/ Newsletter/scope50.pdf.]Search in Google Scholar
[8. Kowalski, Z., Przewrocki, P., Kulczycka, J., Wzorek, Z., Gorazda, K. & Jodko, M. (2004). Risk Analysis of Sewage Sludge - Poland and EU Comparative Approach. Pol. J. Environ.Stud., 13(2), 237-244.]Search in Google Scholar
[9. Dulley, B., (2001). Recycling phosphorus by recovery from sewage. In: Conference Summary - Second International Conference on the recovery of phosphorus from sewage and animal wastes, 12-13 March 2011, Noordwijkerhout, Netherlands.]Search in Google Scholar
[10. Lundin, M., Olofsson, M., Pettersson, G.J. & Zetterlund, H. (2004). Environmental and economic assessment of sewage sludge handling options. Resour. Conserv. Recyc., 41(4), 255-278. DOI:10.1016/j.resconrec.2003.10.006.10.1016/j.resconrec.2003.10.006]Search in Google Scholar
[11. Stark, K., Plaza, E. & Hultman, B. (2006). Phosphorus release from ash, dried sludge and sludge residue from supercritical water oxidation by acid or base. Chemosphere, 62 (5), 827-832. DOI:10.1016/j.chemosphere.2005.04.069.10.1016/j.chemosphere.2005.04.069]Search in Google Scholar
[12. Rittmann, B.E., Mayer, B., Westerhoff, P. & Mark Edwards, M. (2011). Capturing the lost phosphorus. Chemosphere, 84, 846-853. DOI:10.1016/j.chemosphere.2011.02.001.10.1016/j.chemosphere.2011.02.001]Search in Google Scholar
[13. Takahashi, M., Kato, S., Shima, H., Sarai, E., Ichioka, T., Hatykawa, S. & Miyajiri, H. (2001). Technology for recovering phosphorus from incinerated wastewater treatment sludge. Chemosphere, 44, 23-29.10.1016/S0045-6535(00)00380-5]Search in Google Scholar
[14. Stasta, P., Boran, J., Bebar, L., Stehlik, P. & Oral, J. (2006). Thermal processing of sewage sludge. Appl. Therm. Eng., 26(13), 1420-1426. DOI:10.1016/j.applthermaleng.2005.05.030.10.1016/j.applthermaleng.2005.05.030]Search in Google Scholar
[15. Jozuka, T. (2001). P-recovery from sewage sludge incineration ash. CEEP Scope Newsl., 43, 7-8. Retrieved 11 September, 2010, from: http://www.ceep-phosphates.org/Files/ Newsletter/scope43.pdf.]Search in Google Scholar
[16. Suzuki, Y. (2003). P-recovery from sewage-sludge incineration ash. CEEP Scope Newsl., 52, 4-5. Retrieved 22 September, 2011, from: http://www.ceep-phosphates.org/Files/ Newsletter/Scope52.pdf.]Search in Google Scholar
[17. Nakahara, K. & Hoshino, Y. (2000). US Patent No.6022514. Washington, D.C.: US Patents and Trademarks Offi ce.]Search in Google Scholar
[18. Vogel, C., Adam, C., Peplinski, B. & Wellendorf, S. (2010). Chemical reactions during the preparation of P and NPK fertilizers from thermochemically treated sewage sludge ashes. Soil Sci. Plant Nutr, 56(4), 627-635. DOI:10.1111/j.1747- -0765.2010.00485.x.]Search in Google Scholar
[19. Adam, C. , Peplinski, B. , Michaelis, M. , Kley, G. & Simon, F. (2009). Thermochemical treatment of sewage sludge ashes for phosphorus recovery. Waste Manage. 29(3), 1122-1128. DOI: 10.1016/j.wasman.2008.09.011.10.1016/j.wasman.2008.09.01119036571]Search in Google Scholar
[20. Mattenberger, H., Fraissler, G., Brunner, T., Herk, P., Hermann, L. & Obernberger, I. (2008). Sewage sludge ash to phosphorus fertilizer: Variables infl uencing heavy metal removal during thermochemical treatment. Waste Manage., 28 (12), 2709-2722. DOI: 10.1016/j.wasman.2008.01.005.10.1016/j.wasman.2008.01.00518331787]Search in Google Scholar
[21. Mattenberger, H., Fraissler, G., Jöller, M., Brunner, T., Obernberger, I., Herk, P. & Hermann, L. (2010). Sewage sludge ash to phosphorus fertilizer (II): Infl uences of ash and granulate type on heavy metal removal. Waste Manage., 30 (8-9), 1622-1633. DOI: 10.1016/j.wasman.2010.03.037.10.1016/j.wasman.2010.03.03720418087]Search in Google Scholar
[22. Nowak, B., Perutka, L., Aschenbrenner, P., Kraus, P., Rechberger, H. & Winter, F. (2011). Limitations for heavy metal release during thermo-chemical treatment of sewage sludge ash. Waste Manage., 31 (6), 1285-1291. DOI: 10.1016/j. wasman.2011.01.029.]Search in Google Scholar
[23. Donatello, S., Tong, D. & Cheeseman, C.R. (2010). Production of technical grade phosphoric acid from incinerator sewage sludge ash (ISSA). Waste Manage., 30 (8-9), 1634-1642. DOI: 10.1016/j.wasman.2010.04.009.10.1016/j.wasman.2010.04.00920434899]Search in Google Scholar
[24. Franz, M. (2008). Phosphate fertilizer from sewage sludge ash (SSA). Waste Manage., 28(10), 1809-1818. DOI: 10.1016/j. wasman.2007.08.011.]Search in Google Scholar
[25. Gorazda, K., Kowalski, Z., Wzorek, Z., Jodko, M., Rzepecki, T., Kulczycka, J., Przewrocki, P. (2003). Possibilities of Phosphorus Recovering from Municipal Sewage and Sewage Sludge. Pol. J. Appl. Chem., 2, 51-63.]Search in Google Scholar
[26. Gorazda, K. (2004). Research on phosphorus recovery fromsewage sludge formed after simultaneous municipal sewage treatmentwith the use of iron sulfate, as a phosphorus compoundsprecipitating agent. Unpublished doctoral dissertation, Cracow University of Technology, Cracow, Poland.]Search in Google Scholar
[27. Gorazda, K., Wzorek, Z. & Jodko, M. (2005). Phosphorus compounds extraction from the ash after sewage sludge combustion. Pol. J. Chem. Technol., 7(1), 24-28.]Search in Google Scholar
[28. Gorazda, K. & Wzorek, Z. (2006). Selection of leaching agent for phosphorus compounds extraction from the sewage sludge ash. Pol. J. Chem. Technol., 8(3), 15-18.]Search in Google Scholar
[29. Gorazda, K., Wzorek, Z. & Jodko, M. (2007). The infl uence of the thermal processing of sewage sludge on the usage properties of the formed ash. Pol. J. Chem. Technol., 9(4), 21-27. DOI: 10.2478/v10026-007-0083-y. 10.2478/v10026-007-0083-y]Search in Google Scholar