Modeling of Biomethane Production from Multiple Organic Wastes based on Modified ADM1

The Anaerobic Digestion Model No. 1 (ADM1) has been modified to include enhanced kinetic parameters, which more precisely simulate methane production during the anaerobic digestion of diverse organic solid wastes. Calibration and validation of the model were achieved using experimental data from batch fermentation processes. Simulations of the updated ADM1 were conducted using AQUASIM 2.0 software. Sensitivity analysis helped identify and assess the most critical kinetic parameters affecting biogas production. Key parameters such as the microorganism decay constant (d^-1), disintegration rate constant (d^-1), Monod maximum specific substrate uptake rate (gCOD/ gVSS·d), and half⁃saturation constants were found to significantly influence biogas yield. The optimal values for these parameters were identified as 0. 03, 6. 07, 3. 64, and 0. 27, respectively. These optimized values were validated through batch experiments. The modified ADM1 successfully predicted methane production, achieving R² values greater than 0.8 in all validation trials. Key methanogens, Methanosarcina and Methanosaeta, were identified, and their enrichment during mixed fermentation of various organic solid wastes indicated enhanced methane production via aceticlastic methanogenesis. The microbial characterization and simulations using the modified ADM1 model supported each other.