Possibilities for Anaerobic Digestion of Slaughter Waste and Flotates for Biomethane Production

Abstract

Anaerobic digestion for biomethane production is an important tool regarding sustainable energy production. The objective of this study was to investigate the effects of the substrate composition and operating parameters on biomethane production during anaerobic digestion, focusing on the use of flotates and slaughterhouse waste as substrates with a high organic content. A novelty here was the use of a moving bed biofilm reactor (MBBR) with circulation pump for the anaerobic treatment of flotates, slaughter waste (SW), and their mixture. Flotates and waste from slaughterhouses offer a substrate with a high organic content. In this work, it was shown that both substrates provide a high biochemical methane potential (BMP). The highest methane yield was achieved by mixing both substrates. In continuous operation, special challenges arose, due to the high nitrogen and fat content of the substrates. These could be overcome by mixing the substrates and using a circulation pump in the reactor for improved back-mixing. As a result, the highest average methane yield of 0.65 NLCH4·gTS eli−1 was achieved in mesophilic operation at an organic loading rate (OLR) of 4.2 gTS·L−1·d−1.

The Impact of Biochar Additives and Fat-Emulsifying Substances on the Efficiency of the Slaughterhouse Waste Biogasing Process

“…Slaughterhouse waste is one of the most problematic forms of waste due to the threat posed by its improper management. At the same time, it has very high potential in the context of energy use and in the context of returning elements to biocirculation [39]. Ware and Power [49] indicate that the potential for methane production from mixed cattle slaughterhouse waste is 690 dm 3 /kg of waste.…”

“…Due to the limitations of the methanogenesis of slaughterhouse waste, which are related to its chemical composition, this research focused mainly on using this waste as small additions to other materials that improve the input parameters (manure, green waste, sewage sludge, flotates, etc.) [37,39,40]. This research focuses on improving process conditions in a biomass reactor, in which slaughter waste is the main carrier of carbon transferred to methane.…”

Anaerobic Digestion of Olive Mill Wastewater and Process Derivatives—Biomethane Potential, Operation of a Continuous Fixed Bed Digester, and Germination Index

“…Lower HRT and higher OLR resulted in higher hydrolysis and acidification. The stable pH at the outflow indicates that higher OLRs are likely feasible without overacidification [18,19]. The FOS/TAC ratio is a practical indicator that can be determined with simple laboratory equipment and is used by many operators of biogas digesters to determine the biochemical state of the digesters.…”

Bibliometric Analysis of Renewable Natural Gas (Biomethane) and Overview of Application in Brazil

“…Several studies were carried out to reduce biogas from waste, aiming to make full use of residual biomass in a circular economy context [43]. The waste and biomass used in research for biomethane production were the following: slaughterhouse waste as substrates with high organic content [44]; different percentages of fats, oils and grease in anaerobic co-digestion with slaughterhouse wastewater [45]; waste from the agri-food sector, such as chestnut shells [46]; co-digested sheep manure and kitchen waste [47]; effluents from E. coli Energies 2024, 17, 2920 4 of 15 fermenters through anaerobic fermentation using wastewater treatment sludge [48]; straw corn coupled with disk refining to increase biomethane production [49]; and avocado oil and wastewater, which can potentially be digested anaerobically to produce biomethane [50] from pine sawdust [51], okra waste and pig manure [52]; however, landfills and ETEs are more viable sources of biomethane production in terms of cost efficiency [53].…”

“…Most biomethane production is obtained through the anaerobic digestion process, which is an important tool for sustainable energy production [44]. It can be used with different organic waste and is a promising technique to increase the production of clean energy (bioenergy), thus reducing stress on the environment [15,56,57].…”