Removal of COD and nitrogen from animal food plant wastewater in an intermittently-aerated structured-bed reactor.
This study evaluated the performance of a continuous flow structured-bed reactor in the simultaneous removal of total nitrogen (TN) and chemical oxygen demand (COD) in the effluent from an animal food plant. The reactor had an intermittent aeration system; hydraulic retention time (HRT) of one day; temperature of 30 °C; and recirculation ratio of five times the flow. An experimental central composite rotational delineation (CCRD) type design was used to define the aeration conditions and nitrogen load (factors) to be studied. Response surface methodology was used to analyse the influence of the factors above the results, the removal of TN and COD. It was observed that the aeration factor showed the greatest significance for the results and that the affluent TKN concentration did not have a significant effect, at a 95% level of confidence, on COD removal. Throughout the experiment, the COD/N ratio remained between 3.2 and 3.8. The best results for COD and TN removal, 80% and 88%, respectively, were obtained with 158 min of aeration on a cycle of 180 min and 255 mg L(-1) of Total Kjeldahl Nitrogen (TKN) in the substrate.
Department of Food Engineering, State University of Ponta Grossa, Av. Gal. Carlos Cavalcanti 4748, CEP 84030-900, Ponta Grossa, Paraná, Brazil.
Priscila Arcoverde
PA
Wosiack
Department of Civil Construction, State University of Londrina, Rodovia Celso Garcia Cid, Km 380 - Campus Universitário, CEP 86057-970, Londrina, Paraná, Brazil.
Deize Dias
DD
Lopes
School of Engineering of São Carlos, University of São Paulo, Av. Trabalhador São-Carlense 400, CEP13566-590, São Carlos, São Paulo, Brazil.
Márcia Helena
MH
Rissato Zamariolli Damianovic
School of Engineering of São Carlos, University of São Paulo, Av. Trabalhador São-Carlense 400, CEP13566-590, São Carlos, São Paulo, Brazil.
Eugenio
E
Foresti
Department of Food Engineering, State University of Ponta Grossa, Av. Gal. Carlos Cavalcanti 4748, CEP 84030-900, Ponta Grossa, Paraná, Brazil.
Daniel
D
Granato
Department of Food Engineering, State University of Ponta Grossa, Av. Gal. Carlos Cavalcanti 4748, CEP 84030-900, Ponta Grossa, Paraná, Brazil. Electronic address: acbarana@uepg.br.
Ana Cláudia
AC
Barana
D000003:Abattoirs; D000818:Animals; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D008460:Meat; D009584:Nitrogen / Q000737:chemistry*; D062065:Wastewater; D018508:Water Purification / Q000379:methods*
D009584:Nitrogen; D062065:Wastewater
Biological reactor; Denitrification; Nitrification; Removal of carbon; Removal of nitrogen