caa a22 4500 475783786 CHVBK 20180406123652.0 cr unu---uuuuu 170329e20001001xx s 000 0 eng 10.1023/A:1008146421368 doi (NATIONALLICENCE)springer-10.1023/A:1008146421368 High rate algal pond operating strategies for urban wastewater nitrogen removal [Elektronische Daten] [J. García, R. Mujeriego, M. Hernández-Mariné] Two experimental high rate algal ponds (HRAPs) (1.5m2, 570 L per unit), each with a secondaryclarifier for algal biomass separation (0.025 m2,without recirculation), were fed with urban wastewaterfor a one-year period (June 1993 to July 1994). TheHRAPs were installed on the roof of the Department ofHydraulic, Coastal and Environmental Engineering ofthe Technical University of Catalonia, Barcelona,Spain (lat. 41° 24′ 42″ N; long. 2° 7′42″ E). Nitrogen removal efficiency and changes intotal nitrogen, total organic nitrogen,NH4 +-N, and oxidized nitrogen underdifferent hydraulic retention times (HRTs) werecompared. HRAP A was always operated at a higherHRT than HRAP B. Both HRAPs were subjected to thesame environmental conditions of solar radiation, airtemperature and influent water quality. Grab samplesof influent, effluent of the HRAP (mixed liquor) andfinal effluent from the clarifiers were taken once aweek. The annual average nitrogen removal was 73% forHRAP A, and 57% for HRAP B. Higher removal in HRAP Awas due to a lower inorganic nitrogen concentration inits effluent. Significant differences (p> 0.05) inthe relative proportions of nitrogen forms between thetwo HRAPs were observed only in autumn and winter.This was mainly because HRAP B did not achieve a highlevel of NH4 +-N removal by stripping andalgal uptake, as observed in HRAP A. NH4 +-Nstripping was the most important mechanism fornitrogen removal (mean efficiency of 47% and 32% inHRAP A and B, respectively) followed by algal uptake,and subsequent algal separation in the clarifiers(mean efficiency of 26% and 25% in HRAP A and Brespectively). The conclusion of this study is thatHRT determines both the nitrogen removal efficiencyand the distribution of nitrogen forms in the effluentof a HRAP. The nitrogen removal level can becontrolled through suitable HRT operating strategies.By operating at a HRT of 4 days in spring and summer,and 10 days in autumn and winter, nitrogenconcentration in the effluent of a HRAP system can bereduced to less than 15 mg L-1 N. Kluwer Academic Publishers, 2000 algal biomass nationallicence algal uptake nationallicence ammonia stripping nationallicence biological nutrient removal nationallicence high rate algal ponds nationallicence nitrogen nationallicence nutrients nationallicence nitrification nationallicence urban wastewater treatment nationallicence waste stabilisation ponds nationallicence García J. Departamento de Ingeniería Hidráulica, Marítima y Ambiental, ETS de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Cataluña, c/ Gran Capitan s/n, 08034, Barcelona, Spain aut Mujeriego R. Departamento de Ingeniería Hidráulica, Marítima y Ambiental, ETS de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Cataluña, c/ Gran Capitan s/n, 08034, Barcelona, Spain aut Hernández-Mariné M. Departamento de Productos Naturales, Biología Vegetal y Edafología, Facultad de Farmacia, Universidad de Barcelona, c/ Joan XXIII s/n, 08028, Barcelona, Spain aut Journal of Applied Phycology Kluwer Academic Publishers 12/3-5(2000-10-01), 331-339 0921-8971 12:3-5<331 2000 12 10811 https://doi.org/10.1023/A:1008146421368 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1008146421368 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- García J. Departamento de Ingeniería Hidráulica, Marítima y Ambiental, ETS de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Cataluña, c/ Gran Capitan s/n, 08034, Barcelona, Spain aut NATIONALLICENCE 700 1- Mujeriego R. Departamento de Ingeniería Hidráulica, Marítima y Ambiental, ETS de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Cataluña, c/ Gran Capitan s/n, 08034, Barcelona, Spain aut NATIONALLICENCE 700 1- Hernández-Mariné M. Departamento de Productos Naturales, Biología Vegetal y Edafología, Facultad de Farmacia, Universidad de Barcelona, c/ Joan XXIII s/n, 08028, Barcelona, Spain aut NATIONALLICENCE 773 0- Journal of Applied Phycology Kluwer Academic Publishers 12/3-5(2000-10-01), 331-339 0921-8971 12:3-5<331 2000 12 10811 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer