Investigation of the effect of mixing and biomass temperature in the anaerobic digester on the volume of biomethane

Abstract

The article is devoted to the study of the process of biomethane production during anaerobic fermentation in a biomethane installation. The most effective methods for increasing the efficiency of biomethane plants are to increase the intensity of mixing and the temperature of the biomass. However, currently there are various data on the optimal temperature of the fermentation process and the frequency of mixing of biomass per day. A program for conducting experimental studies and an experimental setup for producing biomethane with a bubble-type mixing system has been developed. For research, the central composite rotatable plan of the full factorial experiment was used. Experimental studies of the process of biomethane production during anaerobic fermentation of pig manure in mesophilic temperature conditions were carried out. In the process of implementing the plan, a regression equation was obtained that characterizes the effect of the bubbling mixing intensity and biomass temperature on the biomethane output. Plots of the dependence of the specific yield of biomethane on varied factors are obtained. A rational mode of operation of the biomethane plant has been established, which is achieved with a mixing intensity of 5…6 days−1 and a biomass temperature of 39.5…40.5 °C with a maximum specific yield of biomethane of 393.58 l/kg. This mode can be recommended for the operation of biomethane plants in the processing of organic waste from agricultural enterprises.