Kinetic Considerations on Thermophilic Digestion of Maize Silage at Different Feeding Modes

Abstract

Digestion of maize silage in batch, semi‐batch and continuous mode was investigated under similar experimental conditions with the aim to compare the degradation kinetics. The modeling with the 1st order equation shows that despite the ensiling pre‐treatment the disintegration/hydrolysis step determines the total degradation rate of the substrate. The results confirmed an extremely high adaptation capability of anaerobic biocenosis to increased feeding frequency, rather than to higher but less frequent loadings. 2 – 3 times higher degradation rates were observed for tripled feeding frequency. On the other hand, an increase in organic loading within the same feeding mode always resulted in reduction of digestion rate.

Anaerobic Co-digestion of Agricultural Byproducts with Manure for Enhanced Biogas Production

“…The lower utilization of the co-substrate could probably be corrected by increasing the hydraulic retention time and giving the process more time to fully use the relatively recalcitrant meadow grass. This indicated that meadow grass was a suitable co-substrate for the AD process and that the anaerobic microbial communities of the reactor were already adapted to the substrate . The average methane yields of P-I and P-II (Figure a) had no significant differences ( p > 0.05).…”

“…This indicated that meadow grass was a suitable co-substrate for the AD process and that the anaerobic microbial communities of the reactor were already adapted to the substrate. 35 The average methane yields of P-I and P-II (Figure 4a) had no significant differences (p > 0.05). During period P-III, another steady state was established (days 75−91), with an average methane production rate of 765 ± 31 NmL of CH 4 L −1 day −1 (73% of the expected methane production with 64.0 ± 0.2% CH 4 in the biogas), which was 31% higher (p < 0.05) compared to the methane production rate at period P-II.…”

The Research of Corrected First Order Kinetics on Hydrolysis and Biogas Generation in Batch Anaerobic Digestion

“…1 (ADM1) is the multifaceted model, which represents great complexity and includes an excessive number of parameters [9]. Such a complexity increases the precision of the model, but conversely produces practical complications as all the required data is not often collected [10].…”