Anaerobic Digestion Model No. 1 applied to bioenergy generation from fruit and vegetable waste in Upflow Anaerobic...

This study applied the Anaerobic Digestion Model No. 1 (ADM1) to fruit and vegetable waste (FVW) anaerobic digestion, adjusting substrate-dependent parameters and system configuration in AQUASIM 2.0. Key model parameters were determined, including fractions of carbohydrates, lipids, proteins, and inert particles. Sensitivity analysis identified the decay rate of biomass (k_dec), the disintegration rate constant (k_dis), the hydrolysis rate constant for carbohydrates (k_hyd,ch), the half-saturation constant for acetate (k_s,ac), maximum uptake rates for acetate (k_m,ac), long-chain fatty acids (k_m,fa), and sugars (k_m,su) as the most influential parameters on biogas production. These were estimated using experimental data to refine the model, achieving an R² of 0.99 and root mean square error of 0.34. Inhibition indices confirmed acetate's influence, and free ammonia was observed to interfere with acetate absorption, affecting biogas production. The adjusted ADM1 effectively represented biogas and methane production, demonstrating its applicability to FVW anaerobic digestion systems. The results emphasize the need to adjust ADM1 for different substrates and demonstrate its potential as a valuable tool for identifying potential system failures.