Influence of flow direction in the performance of anaerobic filters

Ronaldo Fia,Filipe Cruz Schuery,Fátima Resende Luiz Fia,Antonio Teixeira De Matos,Alisson Carraro Borges

doi:10.4025/actascitechnol.v34i2.10353

Abstract

This work aimed to evaluate the performance of similar anaerobic filters operating with opposite wastewater flows, and compare mathematical models that describe the kinetics of organic matter degradation in both. Two pilot-scale filters were fed with domestic effluent – one filter worked as upflow (UAF) and the other as downflow (DAF). Experimental COD data obtained from samples taken along the length of the filters were used to fit the first-order mathematical model, the model proposed by Leduy and Zajic (1973) and the model proposed by Brasil et al. (2007). The first model showed overestimated reaction constant (k) values when compared to those obtained using the other models. The models proposed by Brasil et al. (2007) and Leduy and Zajic (1973) presented the highest coefficients of determination (R2). The average removal efficiencies of total COD were equal to 68 and 79% for UAF and DAF, respectively. The results revealed no significant differences between the two filters with regard to the variables applied.

Highlights

Environmental sanitation is an essential factor for improving the health and quality of life of a given population, as well as for environmental preservation
Water flow – upflow or downflow – occurs in the crevices of the bed formed by the support material, on which proliferate microorganisms that can collect as granules and flakes (SINGH; PRERNA, 2009)
The fact that the biomass attaches to a support material provides improved and more consistent performance of anaerobic filters compared to the removal of organic matter in effluent treatment when compared to UASB reactors (JAWED; TARE, 2000)

Summary

Introduction

Environmental sanitation is an essential factor for improving the health and quality of life of a given population, as well as for environmental preservation. Among the actions comprising environmental sanitation are the collection and treatment of wastewater (GALVÃO JUNIOR; PAGANINI, 2009). One type of sewage treatment unit that combines these characteristics is the anaerobic filter, used in communities where the wastewater collection grid is not present (MANARIOTIS; GRIGOROPOULOS, 2006). Anaerobic filters are reactors filled with a layer of support material (bed), on which microorganisms. Water flow – upflow or downflow – occurs in the crevices of the bed formed by the support material, on which proliferate microorganisms that can collect as granules and flakes (SINGH; PRERNA, 2009). The fact that the biomass attaches to a support material provides improved and more consistent performance of anaerobic filters compared to the removal of organic matter in effluent treatment when compared to UASB reactors (JAWED; TARE, 2000)

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Conclusion