IRTA GIRO Joint Research Unit IRTA UPC
IRTA GIRO Joint Research Unit IRTA UPC
Cerrillo M.,Irta Giro Joint Research Unit Irta Upc |
Vinas M.,Irta Giro Joint Research Unit Irta Upc |
Bonmati A.,Irta Giro Joint Research Unit Irta Upc
Journal of Chemical Technology and Biotechnology | Year: 2017
BACKGROUND: Bioelectrochemical systems have been proposed as a possible polishing step for anaerobic digestion (AD). They can also be useful to overcome AD instability in case of AD inhibition while, at the same time recovering ammonia. Continuous assays with a microbial fuel cell (MFC) fed with digested pig slurry were performed to evaluate its operation during malfunction periods of the AD reactor and its feasibility as a strategy to recover ammonia, either by introducing volatile fatty acid (VFA) pulses in the MFC or by inducing AD inhibition. A microbial community assessment was performed to study MFC changes during its operation when fed with the digestate. RESULTS: The MFC achieved COD removal efficiencies of 50% during AD inhibition, reaching a maximum ammonium removal of 31% (11.19 gN m-2 d-1). A high throughput 16S rRNA gene based sequencing assessment revealed that the anode biofilm was different from the digestate fed, showing a reduction in microbial population diversity in the anode after a 182-day-operation period with digested pig slurry. The main enriched populations in the anode belonged to Bacteroidetes (Flavobacteriaceae), Chloroflexi (fermentative bacteria Anaerolineaceae), Methanosarcinaceae and hydrogenotrophic methanogens belonging to Methanobacteriaceae. CONCLUSION: MFCs have proven to be a reliable technology to complement the operation of AD, improving the quality of the effluent and recovering ammonia, particularly during AD inhibition. © 2017 Society of Chemical Industry.
Garcia-Gonzalez M.C.,Agricultural Technological Institute of Castilla and Leon ITACyL |
Riano B.,Agricultural Technological Institute of Castilla and Leon ITACyL |
Teresa M.,Aragon Company of Agri environmental Management S.L.U. SARGA |
Herrero E.,Aragon Company of Agri environmental Management S.L.U. SARGA |
And 8 more authors.
Scientia Agricola | Year: 2016
In this study, eight different manure treatment plants were monitored. The plants were four on-farm and four centralized treatment plants, all of them at full-scale level. Assessment includes a total of seven pre-treatment and process units as follows: mechanical separation, with and without coagulant and flocculant addition, pasteurization, nitrification-denitrification, anaerobic digestion, and composting. The plants are located in nutrient surplus areas of three European Member States (Spain, Italy and Denmark), the majority of these areas being Nitrate Vulnerable Zones (NVZ). Results presented herein are data collected over a six-month period and comprise performance data of the treatment plants, pathogen indicators (E.coli and Salmonella) and greenhouse gas (GHG) emissions data under two scenarios: 1) the baseline scenario and 2) the treatment plant scenario. The assessment includes GHG emissions of the storage facilities, transportation, and subsequent intermediate storage, electric consumption, electric production, composting, and land application. All treatment plants studied generated a significant reduction in GHG emissions (between 53 and 90 %) in comparison to the baseline scenario. Organic matter and total solids (TS) content in manure were also greatly reduced, with values ranging between 35-53 % of chemical oxygen demand (COD) and, 24-61 % of TS for anaerobic digestion (AD) treatment plants, 77-93 % COD and 70 % TS in the case of AD combined with nitrogen (N)- removal unit plants. Nitrogen concentrations were also greatly reduced (between 65-85 %) total Kjeldahl nitrogen (TKN) and 68-83 % ammonium (NH4 +-N)) in plants with N-removal units. © 2016, Scientia Agricola. All rights reserved.