Overview of Numerical Simulation of Solid-State Anaerobic Digestion Considering Hydrodynamic Behaviors, Phenomena of Transfer, Biochemical Kinetics and Statistical Approaches

Abstract

Anaerobic digestion (AD) is a promising way to produce renewable energy. The solid-state anaerobic digestion (SSAD) with a dry matter content more than 15% in the reactors is seeing its increasing potential in biogas plant deployment. The relevant processes involve multiple of evolving chemical and physical phenomena that are not crucial to conventional liquid-state anaerobic digestion processes (LSAD). A good simulation of SSAD is of great importance to better control and operate the reactors. The modeling of SSAD reactors could be realized either by theoretical or statistical approaches. Both have been studied to a certain extent but are still not sound. This paper introduces the existing mathematical tools for SSAD simulation using theoretical, empirical and advanced statistical approaches and gives a critical review on each type of model. The issues of parameter identifiability, preference of modeling approaches, multiscale simulations, sensibility analysis, particularity of SSAD operations and global lack of knowledge in SSAD media evolution were discussed. The authors call for a stronger collaboration of multidisciplinary research in order to further developing the numeric simulation tools for SSAD.

Modeling of the Anaerobic Digestion of Biomass Produced by Agricultural Residues in Greece

“…Continuing from the aforementioned processes, carbon monoxide (CO) undergoes distinct transformations within the anaerobic digestion system, described by Equations ( 7)- (9). These reactions illustrate the diverse pathways in which carbon monoxide can be transformed, involving the production of hydrogen, acetate, and other intermediate compounds.…”

“…The anaerobic digestion model 1 (ADM1), a popular multi-step timedependent model, was implemented and presented by Batstone et al [8] and has been included as standard in AQUASIM. While ADM1 incorporates dynamics and various state variables, its complexity poses numerical challenges for real-time implementation [9]. Despite a clear understanding of the biochemical mechanisms in the AD process, the specific pathway of biogas formation remains uncertain.…”

“…To address these uncertainties, deriving biogas amounts directly from substrate theoretical yields, combined with measured parameters, is a practical approach for estimating biogas production. However, estimating and measuring parameters can be challenging, time-consuming, laborious, and expensive [9,10]. The present work aims to adapt the ADM1 simulation code, previously implemented in the software platform AQUASIM, to a laboratory-level AD reactor, as described by Aravani et al [11] and Aravani et al [12].…”

A Mass Balance-Based Method for the Anaerobic Digestion of Rice Straw

“…The system assumed as reference for this study is a single-stage low solids anaerobic digester (LSAD) with a dry matter (DM) content lower than 15% [86].…”