Abstract
Resource recovery from wastewater, preferably as high value products, has become an integral part of modern wastewater treatment. This work presents the potential to produce single cell protein (SCP) from pre-settled piggery wastewater (PWW) and meat chicken processing wastewater (CWW), utilising anaerobic purple phototrophic bacteria (PPB). PPB were grown as biofilm in outdoors 60 L, 80 L and 100 L flat-plate reactors, operated in sequential batch mode. PPB biofilm was recovered from reactor walls at a total solid (TS) content ∼90 g•L − 1, and the harvested biomass (depending on the wastewater) had a consistent quality, with high protein contents (50–65%) and low ash, potentially applicable as SCP. The COD, N and P removal efficiencies were 71±5.3%, 22±6.6%, 65±5.6% for PWW and 78±1.8%, 67±2.7% and 37±4.0% for CWW, respectively, with biofilm areal productivities up to 14 g TS•m − 2•d − 1. This was achieved at ammonium-N concentrations over 1.0 g•L − 1 and temperatures up to 55 °C and down to 6 °C (daily fluctuations of 20–30 °C). The removal performances and biomass productivities were mostly dependent on the bioavailable COD in the form of volatile fatty acids (VFA). At sufficient VFA availability, the irradiance became limiting, capping biofilm formation. Harvesting of the suspended fraction resulted in increased productivities and recovery efficiencies, but lowered the product quality (e.g., containing undesired inerts). The optimum between quantity and quality of product is dependent on the wastewater characteristics (i.e., organic degradable fraction) and potential pre-treatment. This study shows the potential to utilise sunlight to treat agri-industrial wastewaters while generating protein-rich PPB biomass to be used as a feed, feed additive or feed supplement.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.