Goat Manure Potential as a Substrate for Biomethane Production—An Experiment for Photofermentation

This article presents the current state of biogas (biomethane) production technology—an example of the use of goat manure in terms of photofermentation efficiency. The theoretical and experimental potential of biomethane using biodegradability for anaerobic fermentation of goat manure was indicated. Goat manure was tested for its elemental composition to determine the suitability of this raw material for biogas production. The quality of biogas produced under atmospheric conditions from goat manure placed in a reactor (photodigester) was assessed. An attempt was made to determine the process conditions for immobilization on a goat manure bed (depending on the research material collected), which allows for demonstrating the activity of the fermentation bacterial flora, thus influencing the amount of biogas (biomethane) produced in the reactor. A mechanism for the photofermentation process involving the production of biomethane was developed. The novelty of this article is the development of the use of goat manure in an innovative way, pointing to the development of the biomethane industry. When comparing goat manure, active group (compact bed), it should be noted that K 3.132%, Na 0.266%, Ca 1.909% and Mg 0.993% are lower values compared to the material with values of K 3.397%, Na 0.284%, Ca 1.813% and Mg 0.990% which are higher. This is undoubtedly due to the presence of nutrients in the deposit that support the biomethane production process. The active group (compact bed) material A shows a dynamic increase in biomethane production with lower nutrient values. However, material B, having a higher percentage of ingredients, shows stabilization of biomethane production after the sixth month of the process. Technological trends and future prospects for the biomethane sector were initiated.