Urine nitrification and sewer discharge to realize in-sewer denitrification to simplify sewage treatment in Hong Kong.

The chemically enhanced primary treatment works in Hong Kong will be upgraded for biological nitrogen removal. This study proposed a novel approach to waive the upgrading by urine source-separation, onsite nitrification and discharge of nitrified urine into sewers to achieve in-sewer denitrification. Human urine was collected and a lab-scale experiment for full urine nitrification was conducted. The results showed that full nitrification was achieved with alkaline addition. Simulation of nitrified urine discharge into an 8-km pressure main in Hong Kong was conducted with a quasi-2D dynamic sewer model developed from a previously calibrated sewer biofilm model. It was assumed that 70% of the residents' urine was collected and fully nitrified on-site. The simulation results revealed that the proposed approach is effective in removal of nitrogen within the sewer, which decreases ammonia-N at the sewer outlet to a level required for secondary effluent discharge in Hong Kong.

[1]  Guanghao Chen,et al.  Utilization of oxygen in a sanitary gravity sewer , 2000 .

[2]  J Lienert,et al.  Young users accept NoMix toilets--a questionnaire survey on urine source separating toilets in a college in Switzerland. , 2006, Water science and technology : a journal of the International Association on Water Pollution Research.

[3]  J Lienert,et al.  Real-life efficiency of urine source separation. , 2009, Journal of environmental management.

[4]  H. Kirchmann,et al.  Human urine - Chemical composition and fertilizer use efficiency , 2004, Fertilizer research.

[5]  Guang-hao Chen,et al.  Biofilm in the sediment phase of a sanitary gravity sewer. , 2003, Water research.

[6]  M C M van Loosdrecht,et al.  Effects of separate urine collection on advanced nutrient removal processes. , 2004, Environmental science & technology.

[7]  Hermann H. Hahn,et al.  Characterization of the municipal wastewaterpart human urine and a preliminary comparison with liquid cattle excretion , 1998 .

[8]  F Jiang,et al.  A New Method for Determination of Parameters in Sewer Pollutant Transformation Process Model , 2007, Environmental technology.

[9]  Willi Gujer,et al.  Urea hydrolysis and precipitation dynamics in a urine-collecting system. , 2003, Water research.

[10]  M. V. van Loosdrecht,et al.  A biofilm model for prediction of pollutant transformation in sewers. , 2009, Water research.

[11]  Keshab Sharma,et al.  A pilot study for wastewater reclamation and reuse with MBR/RO and MF/RO systems , 2007 .

[12]  H Siegrist,et al.  Nitrification and autotrophic denitrification of source-separated urine. , 2003, Water science and technology : a journal of the International Association on Water Pollution Research.

[13]  花田 茂久,et al.  Activated Sludge Model No.3 (ASM3) へのリン除去モジュールの導入とそのキャリブレーション方法の開発 , 2004 .

[14]  M. V. van Loosdrecht,et al.  Evaluation of separate urine collection and treatment to augment existing wastewater treatment works. , 2005, Water science and technology : a journal of the International Association on Water Pollution Research.

[15]  J Vollertsen,et al.  The sewer as a bioreactor--a dry weather approach. , 2002, Water science and technology : a journal of the International Association on Water Pollution Research.

[16]  M. Maurer,et al.  Source separation: will we see a paradigm shift in wastewater handling? , 2009, Environmental science & technology.

[17]  J L Huisman,et al.  Modelling wastewater transformation in sewers based on ASM3. , 2002, Water science and technology : a journal of the International Association on Water Pollution Research.

[18]  J. Heijnen,et al.  Aerobic granulation in a sequencing batch reactor , 1999 .