A novel process simulation model (PSM) for anaerobic digestion using Aspen Plus.

Area of Science:

• Biotechnology and Bioengineering
• Environmental Engineering
• Chemical Engineering

Background:

• Anaerobic digestion is a key process for biogas production.
• Accurate modeling is crucial for optimizing biogas yield and digester performance.
• Existing models may lack comprehensive features for diverse substrates and conditions.

Purpose of the Study:

• To develop a novel and comprehensive process simulation model (PSM) for biogas production in anaerobic digesters.
• To predict biogas yields from various substrates under different operational parameters.
• To validate the model's accuracy using experimental data.

Main Methods:

• Developed a process simulation model (PSM) using Aspen Plus®.
• Incorporated 46 reactions, including inhibitions, kinetics, pH, ammonia, and retention time.
• Modeled hydrolysis reactions by extent and acidogenic, acetogenic, and methanogenic reactions by kinetics.
• Validated the PSM against laboratory and industrial anaerobic digestion data.

Main Results:

• The model accurately predicts biogas production across various conditions.
• Statistical analysis (P-value = 0.701) confirmed no significant difference between model predictions and experimental data.
• Sensitivity analysis showed a minor deviation (5.285%) for a ±10% change in substrate composition and reaction extent.

Conclusions:

• The developed PSM is a reliable tool for simulating biogas production in anaerobic digesters.
• The model's comprehensive approach allows for accurate predictions across diverse substrates and process conditions.
• The validated model can aid in optimizing anaerobic digestion processes for enhanced biogas yield.