Anaerobic co digestion from cattle manure, pig manure and horse manure as an alternative to improve the energy potential in household digesters

Abstract

The manures from bovine (EB), equine (EE) and porcine (EP) are among the most abundant renewable waste in agroecosystems, which can be managed and avoid contamination problems, and one option is a stabilization by anaerobic digestion (DA). This study was carried out to reflect the biochemical and microbiological behavior of mixtures of dilutions from bovine, equine and porcine manures and according to the proportions described by the simplex experiment design {3,3} augmented with axial points, having consider as response variables the potential of biomethanation (PBM) for the biochemical part and the synergy (Φ) for the microbiological part. Characterization of the physical properties was performed before performing the experiments for the determination of the PBM. For the DA of the case studies, the equine-bovine manure mixture with a ratio in % P / P 8,3% and 16,7% respectively and remaining in water, generated the greatest synergy 3,63 and achieved the second-best potential 46,56 N-lCH4 / kg SV, showing how equine manure is an excellent co-substrate for bovine manure and equine-porcine manure mixture with a ratio in % P / P 16,7% and 8,3% respectively and remaining in water, reached the highest PBM of 51,22 N-lCH4 / kg SV with a synergy 3,09 being the second-highest among all digestions, indicating how these manures complement their biochemical and microbiological qualities to obtain a greater result. As for the analysis of the digested energy potential, the highest energy production is 0,43 kWh / kg from the EE-EP mixture and the substrate that generates the least amount of energy is bovine manure with 0,08 kWh / kg of sample.