Rapid generation of volatile fatty acids (VFA) through anaerobic acidification of livestock organic waste at low hydraulic residence time (HRT)

• Published in: Bioresource technology 2017-08, Vol.238, p.188-193
• Main Authors: Kuruti, Kranti, Nakkasunchi, Shalini, Begum, Sameena, Juntupally, Sudharshan, Arelli, Vijayalakshmi, Anupoju, Gangagni Rao
• Format: Article
• Language: English
• Subjects: Anaerobic digestion; Anaerobiosis; Animals; Cattle; Cattle manure; F/M ratio; Fatty Acids, Volatile; Livestock; Manure; Poultry; Poultry litter; Pre-treatment; VFA
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2017.04.005

Acidogenic anaerobic digestion of livestock organic waste for the production of volatile fatty acids at low hydraulic residence time (HRT). [Display omitted] •Rapid generation of VFA’s through acidogenic anaerobic digestion from CM and PL.•Pre-treatment of CM and PL, optimization of pH, HRT and F/M ratio to maximize VFAs.•HRT of 4days, pH of 5.5, and F/M ratio of 1.0 were found optimum for the process.•Pre-treated CM and PL yielded 0.43 and 0.67kg of VFA/(kg VS reduced) respectively. The purpose of this study was to investigate the effect of pre-treatment and F/M (Food to Microorganism) ratios for the rapid generation of volatile fatty acids (VFA) from livestock organic wastes (cattle manure (CM) and poultry litter (PL)) through an anaerobic acidification process at a pH range of 4.5–5.5. Experiments were organized using CM and PL in batch reactors (1L and 25L) with and with no pre-treatment of substrate at F/M ratios (0.4, 0.6, 0.8 and 1). Among various existing pre-treatments methods, thermal-acidic (120°C; 1% H2SO4) pre-treatment was found effective. The results revealed that 0.31 and 0.47kg VFA/(kg VS reduced) could be obtained from CM and PL respectively with no pre-treatment, whereas it improvised to 0.43 and 0.67kg VFA/(kg VS reduced) correspondingly due to pre-treatment. Aforesaid, better yield of VFA was obtained at F/M ratio of 1.0, pH-5.5 and hydraulic residence time of 4days.