Optimization of Reactor Parameters in Anaerobic Digesters

Study of the parameters of biogas plants

“…Let`s take into consideration a biogas plant with a 100 m 3 vertical fermentation reactor operating in the mesophilic (32°C) and thermophilic (55°C) range of biomass fermentation temperatures, in a continuous and batch process of biomass fermentation with a 70-90% filling of the reactor [18][19][20][21][22][23]. Let's take the range of ambient air temperature from 20°C to -20 °C, respectively, the initial temperature of the biomass is taken to be 20°C and 10°C.…”

“…Figures 5 and 6 show that the biomass cooling line in a 100 m3 reactor lies to the right (above) the limit of the permissible temperature drop within the fermentation temperature range, which indicates that even without insulation, a 100 m 3 reactor can withstand a temperature jump. However, it should be remembered that mesophilic bacteria are characterized by a range from 30 to 40°C [18][19][20][21][22]. Therefore, marking on the temperature axis 50°C (the temperature rise inside the reactor over the ambient temperature) and keeping this value parallel to the time axis until it intersects with the graphs, we find that for the mesophilic process of biomass fermentation with an initial excess of 52°C in the absence of insulation, a temperature range of no more than 5 hours.…”

“…The higher the temperature of the fermentation process, the more stringent the requirements for the permissible temperature fluctuations for optimal gas formation: with mesophilic -± 1 ° C per hour; thermophilic -± 0.5 ° С per hour [18][19][20][21][22][23]. The shift of the cooling temperature from the area of one biomass fermentation process to the temperature range of another process should also be considered a violation of the requirements for the choice of parameters of biogas plants, since the family of already existing bacteria may not survive at other temperatures.…”

“…The power for heating the daily dose of the substrate with continuous loading of the bioreactor depends on the volume and temperature, as well as the heating time [16,18,[20][21][22][23][24][25]:…”