Increasing Biogas Yield During Methane Fermentation of Extruded Straw in a Mixture with Cattle Manure

After harvesting wheat, excess straw remains, which, together with cattle waste, on the basis of anaerobic digestion, can be processed into biogas, as well as into high-quality fertilizers. However, at the moment there is no scientific and methodological apparatus for substantiating the technology of biomass preparation and its fermentation in order to obtain the maximum volumes of biogas for the production of heat and electricity. Achievement of this goal involves the solution of the following experimental and theoretical problems: the study of various methods of preparation and fermentation of biomass, the development of a scientific and methodological apparatus for choosing a rational (suboptimal) method for the preparation and processing of straw with cattle manure. The conceptual basis for increasing the yield of biogas is the preparation of biomass for biogas plants in the form of special pellets with different concentrations of slaked lime. To evaluate the effectiveness of various methods of preparation and fermentation of biomass, the yield of biogas from pellets was determined without the use of slaked lime, with a lime concentration of 50 kg/t, 100 kg/t and 150 kg/t of straw. The most significant result was increase in biogas output by more than 60%.