Advances in Engineering Advances in Engineering features breaking research judged by Advances in Engineering advisory team to be of key importance in the Engineering field. Papers are selected from over 10,000 published each week from most peer reviewed journals.
Chemical Engineering Journal, Volume 228, 2013, Pages 87-92.
Pasiano Rivas-García, José E. Botello-Álvarez, Alejandro Estrada-Baltazar, José L. Navarrete-Bolaños.
Department of Chemical Engineering, Technological Institute of Celaya, Av. Tecnológico y A. García Cubas S/N, C.P. 38010, Celaya, Guanajuato, Mexico and
Department of Biochemical Engineering, Technological Institute of Celaya, Av. Tecnológico y A. García Cubas S/N, C.P. 38010, Celaya, Guanajuato, Mexico.
Abstract
In this study, the interactions between the microbial populations in an anaerobic digester leading to the acidification of the fermentation medium were investigated using numerical simulation in the Anaerobic Digestion Model No. 1 (ADM1). The anaerobic digestion of cattle manure at 10 g volatile solids (VSs)/L and 35 °C was used as the case study. The numerical runs were performed using a factorial experimental approach with two levels. The minimum pH reached in the digestion was considered the response variable, whereas the initial concentrations of the main microbial groups included in the ADM1 were considered the factors. The statistical analysis demonstrated that the initial concentration of acetoclastic bacteria was the most critical variable in the acidification of the medium. It was estimated that permanent acidification occurred when the initial concentration of this group of microorganisms was less than or equal to 0.0838 g chemical oxygen demand (COD)/L, regardless of the population density of the other microbial groups.
