Systematic simplification of the Anaerobic Digestion Model No. 1 (ADM1) - Laboratory experiments and model...

Area of Science:

• Biotechnology
• Environmental Engineering
• Process Engineering

Background:

• Established process models like the Anaerobic Digestion Model No. 1 (ADM1) are underutilized in agricultural biogas plants due to limited data.
• Effective monitoring and control of biogas production require reliable and applicable process models.

Purpose of the Study:

• To implement and evaluate simplified versions of the ADM1 for simulating anaerobic digestion of agricultural substrates.
• To assess the accuracy of simplified models in predicting biogas production rates and key intermediates.

Main Methods:

• Process simulation of semi-continuous anaerobic digestion experiments using various agricultural and industrial residues.
• Implementation and comparison of different simplified ADM1 model structures.
• Evaluation of objective functions and parameter values on hydrolysis constants and microbial growth rates.

Main Results:

• Simplified model structures accurately depicted biogas production rates and intermediates (ammonium nitrogen, propionic and acetic acid).
• Model performance was comparable to the original ADM1.
• The study identified the impact of objective functions and parameter values on model estimates.

Conclusions:

• Simplified ADM1 models are suitable for practical application in agricultural biogas plants.
• Reduced parameter requirements and suitable system characteristics make simplified models advantageous.
• These models provide a reliable basis for model-based monitoring and control of biogas processes.