CSTR based Semi-Dry Fermentation Process
Salient features of the technology
- CSTR Semi-Dry Fermentation Technology: Designed for
agro wastes like paddy straw, press mud, cane trash,
Napier grass, poultry litter and more.
Over 100 Operational Plants in Europe: Demonstrating
the technology's success and widespread use.
Developed by Dr. Friedmann: Co-founder of J & F Biogas,
the technology originated in 2002-2003.
Space and Cost Efficiency: J&F's process-based digester
reduces digester footprint and ground work costs.
Reduced Internal Power Requirement: Digesters
consume only 50% of power compared to other
Repowering Opportunities: Existing plants can be
improved through process optimization.
J & F biogas High load reactors
The loading rate of J & F biogas reactors are in the range of 8 to 14 kgs of ODM per m3 of reactor volume. Conventional reactors have a loading rate between 2 to 5 kg of ODM per m3. High loading rate is one of the main operating principles of J&F reactors. This process is particular suitable for substrates with 30-35 % DM content.
The main advantage of J & F process plant is a flexibility regarding the feedstock. If there are any changes in DM content of the feedstock’s from the initial design , for example sudden change of feedstock due to unavailability of planned feedstock’s will only have a less impact of operation of J & F process based digesters. The digesters and the robust components can adjust to the change of mix in feedstock’s.
Comparison of CSTR Semi-dry Fermentation Vs other technologies
|CSTR semi Dry Fermentation
|Size of digester(M3)
|700 to 10,000 M3
|Due to lesser number of digesters/agotators and containerized feeding system the power required will be 50% of other technologies
|Number of agitators reuired will be two times CSTR semi dry process and multiple pumps will be required for pumping slurry at various stages
|water/slurry required for feed stocks
with 30% solids and 70% moisture
Dry matter %
|up to 35%
|co digestion with Multi feed stocks
|Greater flexibility with co-digestion with other feed stocks such as straw poultry litter etc
|Lesser flexibility for co-digestion with feed stocks with higher dry matter more water will be required for dilution
|Liquied effluent /slurry generated post digestion
|Minimal liquid slurry generation due to higher viscosity inside the digester
|liquid slurry generation will be higher
|Operation and maintenance
|Low(Agitator life time of 8+ years)
|Medium (Agitators will require regular maintenance)