Comparison of Energetic Potential of Disposal of Slaughterhouse Waste by Incineration and Methanogenesis

The circular economy necessitates the identification of waste management methods that minimise the use of environmental resources and do not generate secondary waste streams, whose management poses further challenges. The aim of this analysis was to evaluate the environmental and energy performance of slaughterhouse waste treatment using anaerobic digestion and incineration. The quantity of greenhouse gases emitted during slaughterhouse waste processing was adopted as the evaluation criterion. Although the incineration of slaughterhouse waste delivered a higher net energy yield compared with anaerobic digestion, it was characterised by substantially higher carbon dioxide emissions per unit of energy. Anaerobic digestion of poultry slaughterhouse waste demonstrated superior environmental performance, provided that the resulting digestate is utilised as a source of plant nutrients. The modification of the anaerobic digestion technology did not lead to a reduction in greenhouse gas emissions per unit of energy produced. The most effective method for the treatment of poultry slaughterhouse waste was anaerobic digestion without co-digestion, combined with the use of digestate as a feedstock for fertiliser production. For small slaughterhouses generating less than 3 tonnes of waste per day, incineration was the more rational solution. The efficient utilisation of slaughterhouse waste critically depends on its processing at the place of generation.