MarÃa C. Veiga
University of A Coruña, Spain
Title: Biodegradable polymers from brewery wastewater
Biography
Biography: MarÃa C. Veiga
Abstract
Brewery mills generate large volumes of wastewater that is characterized by high content of easily degradable organic matter, mainly volatile fatty acids, ethanol and sugars that can be used as substrate to produce polyhydroxyalkanoates (PHA). The PHA production process was developed in a three-step process: acidogenic fermentation of wastewater, selection of a culture with high storage capacity fed with acidogenic effluent and finally a storage step. The acidogenic fermentation of brewery wastewater was carried out in a sequencing batch reactor (SBR) at pH 6, obtaining an acidification of 70%. Fed-batch assays were performed using the enriched biomass, obtaining a maximum of 70 % PHA on a cell dry weight basis and a storage yield of 0.75 Cmmol PHA/Cmmol VFA. Moreover some polymer properties like temperature melting and crystallization or thermal stability were determined. A study of the mixed microbial cultures was also performed in order to identify the dominant strains of PHA accumulating microorganisms. To further assess the industrial relevance of the waste-based PHA process, the second step was studied in a semi-pilot scale reactor. Acknowledgements: The present research was financed through project CTQ2013-45581-R from the Spanish Ministry of Economy and Competitiveness.