The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous fro...The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.展开更多
A two-stage upflow anaerobic sludge blanket （UASB） and sequencing batch reactor （SBR） system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to impro...A two-stage upflow anaerobic sludge blanket （UASB） and sequencing batch reactor （SBR） system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to improve the total nitrogen （TN） removal efficiency and to reduce the COD requirement for denitrification, the raw leachate with recycled SBR nitrification supematant was pumped into the first-stage UASB （UASB1） to achieve simultaneous denitrification and methanogenesis. The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency. When the organic loading rates of UASB1, UASB2 and SBR were 11.95, 1.63 and 1.29 kg COD/（m^3.day）, respectively, the total COD removal efficiency of the whole system reached 96.7%. The SBR acted as the real undertaker for NH4^＋-N removal due to aerobic nitrification. The system obtained about 99.7% of NH4^＋-N removal efficiency at relatively low temperature （14.9-10.9℃）. More than 98.3% TN was removed through complete denitrification in UASB 1 and SBR. In addition, temperature had a significant effect on the rates of nitrification and denitrification rather than the removal of TN and NH4^＋-N once the complete nitrification and denitrification were achieved.展开更多
文摘The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.
基金supported by the National Natural Science Foundation of China (No.50978003)the Beijing Natural Science Foundation (No.8091001)+1 种基金the Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality (No.PHR20090502)the State Key Laboratory of Urban Water Resource and Environment (No.QAK200802)
文摘A two-stage upflow anaerobic sludge blanket （UASB） and sequencing batch reactor （SBR） system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature. In order to improve the total nitrogen （TN） removal efficiency and to reduce the COD requirement for denitrification, the raw leachate with recycled SBR nitrification supematant was pumped into the first-stage UASB （UASB1） to achieve simultaneous denitrification and methanogenesis. The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency. When the organic loading rates of UASB1, UASB2 and SBR were 11.95, 1.63 and 1.29 kg COD/（m^3.day）, respectively, the total COD removal efficiency of the whole system reached 96.7%. The SBR acted as the real undertaker for NH4^＋-N removal due to aerobic nitrification. The system obtained about 99.7% of NH4^＋-N removal efficiency at relatively low temperature （14.9-10.9℃）. More than 98.3% TN was removed through complete denitrification in UASB 1 and SBR. In addition, temperature had a significant effect on the rates of nitrification and denitrification rather than the removal of TN and NH4^＋-N once the complete nitrification and denitrification were achieved.
