Treatment of low strength sewage with high suspended organic matter content in an anaerobic sequencing batch reactor and modeling application

 Andrés Donoso-Bravo*
Escuela de Ingeniería Bioquímica
Pontificia Universidad Católica de Valparaíso
General Cruz 34, Valparaíso, Chile
Tel: 56322273819
Fax: 56322273803
E-mail: andres.donoso.b@mail.ucv.cl

Marta Carballa
Escuela de Ingeniería Bioquímica
Pontificia Universidad Católica de Valparaíso
General Cruz 34, Valparaíso, Chile
Valparaíso, Chile

Gonzalo Ruiz- Filippi
Escuela de Ingeniería Bioquímica
Pontificia Universidad Católica de Valparaíso
General Cruz 34, Valparaíso, Chile
Valparaíso, Chile

Rolando Chamy
Escuela de Ingeniería Bioquímica
Pontificia Universidad Católica de Valparaíso
General Cruz 34, Valparaíso, Chile
Valparaíso, Chile

*Corresponding author

Financial support: FONDECYT project (n°1080329).

Keywords: acidogenesis, anaerobic treatment, hydrolysis, low strength wastewater, modeling.

In this work, an anaerobic sequencing batch reactor (ASBR) was operated for 8 months to treat low strength sewage with high suspended organic matter content. Three phases of operation with increasing organic loading rates (OLR) were performed: 0.4 kg COD/m³ x d (phase I), 0 .8 kg COD/m³ x d (phase II) and 1.2 kg COD/m³ x d (phase III). Adequate stability parameters (pH, total alkalinity) were obtained through all three experimental phases. During phases I and II, the removal efficiencies of organic matter (expressed as total chemical oxygen demand (COD) and total suspended solids ranged between 50-60%. However, these values decreased to 15-25% in phase III. In addition, a non-complex model, including hydrolysis, acidogenesis and methanogenesis, was applied to predict the reactor behavior.