Experimental and modeling study of a two-stage pilot scale high solid anaerobic digester system.

Area of Science:

• Environmental Engineering
• Biotechnology
• Waste Management

Background:

• Municipal solid waste (MSW) presents significant disposal challenges.
• Anaerobic digestion is a promising technology for organic waste treatment.
• High solid anaerobic digestion (HSAD) offers advantages for handling solid organic waste.

Purpose of the Study:

• To develop and validate a comprehensive model for a novel two-stage HSAD system.
• To simulate the anaerobic digestion of the organic fraction of municipal solid wastes (OFMSW).
• To assess the model's ability to predict key process parameters.

Main Methods:

• Configuration of a two-stage HSAD system with natural zone separation.
• Development of a model combining Continuous Stirred-Tank Reactor (CSTR) and Advective-Diffusive Reactor (ADR) modules.
• Incorporation of Anaerobic Digestion Model No. 1 (ADM1) for reaction kinetics.

Main Results:

• The HSAD reactor naturally separated into solid and liquid zones.
• The integrated CSTR-ADR model accurately simulated the two-stage system.
• Simulation results closely matched experimental data for pH, volatile fatty acid (VFA), and biogas production.

Conclusions:

• The developed model provides a reliable tool for configuring and optimizing HSAD systems for OFMSW.
• The study demonstrates the effectiveness of HSAD in treating highly degradable organic waste.
• Accurate prediction of key parameters enhances the design and operation of anaerobic digesters.