Modified anaerobic digestion model No.1 (ADM1) for modeling anaerobic digestion process at different ammonium concentrations

Abstract

Anaerobic digestion (AD) is an established method for sustainable energy production. Anaerobic digestion model No.1 (ADM1) was used to simulate methane production (MP) and volatile fatty acid (VFA) concentrations at different ammonium concentrations. In accordance with the incomplete description of several biochemical reactions and the omission of several reaction processes, ADM1 was modified with the consideration of acetic acid inhibition and valeric acid existence. ADM1_ac (ADM1 added acetic acid inhibition) could obtain better simulation accuracy of MP (goodness‐of‐fit value = 0.945), and VFA concentrations (goodness‐of‐fit values > 0.39) were all higher than ADM1_original, but cannot explain the valeric acid production. ADM1_va (ADM1 added valeric acid existence) could achieve better simulation of valeric acid (achieving a breakthrough of zero), nevertheless the accuracy of propionic and butyric acids was poorer than ADM1_ac with differences between experimental and simulation values were 5%–10% lower. With both factors coordinated, MP and VFA concentrations could be simulated accurately by ADM1_ac_va (ADM1 added acetic acid inhibition and valeric acid existence), with the highest goodness‐of‐fit values (>0.85). The results of a verification experiment with ADM1_ac_va simulation further indicated that acetic acid inhibition and valeric acid as new component were both important in ADM1. Practitioner points ADM1_ac could simulate MP and acetate, propionate and butyrate concentrations better. ADM1_va could explain the valerate production during AD of glucose. ADM1_ac_va could simulate AD process quite accurately, with the highest goodness‐of‐fit values (>0.85). Acetate inhibition and valerate existence were both important and should be considered in ADM1.

Thermophilic Anaerobic Co-Digestion of Exhausted Sugar Beet Pulp with Cow Manure to Boost the Performance of the Process: The Effect of Manure Proportion

“…These high TVFA values may be related to the inhibition of acetoclastic methanogenesis [42]. Li, X. et al [43] reported that in the AD process, valeric acid is not normally generated in appreciable amounts and that the formation of this VFA is due to the reversibility of the biochemical reactions of acetic acid, propionic acid, and hydrogen.…”

Not Just Numbers: Mathematical Modelling and its Contribution to Anaerobic Digestion Processes

“…As noted earlier, the model is far from perfect but its flexibility and structure means it is suitable as a tool to be used at the design stage of AD plant development, for qualitative scenario testing, or for benchmarking control schemes [63][64][65]. As with the ASMs, modifications to the model have been implemented based on process requirements, such as operating mode [66,67], or to include new biochemical processes [68,69]. A more comprehensive transition to a consensus ADM No.…”

“…Such a multi-scale model is highly complex and requires a large degree of multi-disciplinarity to ensure successful implementation. However, the use of IbMs is becoming more ubiquitous and recent efforts to develop large scale simulators of EBS using hybrid IbM and statistical emulators have established a framework for studying microbial community behaviour at scale [69,173,174], opening the door for application to anaerobic digestion processes [172,175] (See Fig. 5 for an example application of an IbM applied to anaerobic processes).…”

Modeling, instrumentation, automation, and optimization of water resource recovery facilities (2019) DIRECT

“…The two-phase (solid, liquid) model simulated the increasing diameter granular biomass using a multilayer biofilm model. Using laboratory-scale thermophilic glucose digestion data for model verification, the ADM1 digestion model was extended to incorporate the valeric acid dynamics and acetic acid inhibition (Li, Yang, Liu, Ma, & Wang, 2019). Miletic, Rieger, Schraa, and Wade (2019) presented the concept of a statistical partial least squares model for predicting the wastewater orthophosphate concentration based on its multivariate correlation with the wastewater concentrations of chemical oxygen demand (COD), TSS, ammonia, pH, dissolved oxygen (DO), and temperature.…”

“…The two‐phase (solid, liquid) model simulated the increasing diameter granular biomass using a multilayer biofilm model. Using laboratory‐scale thermophilic glucose digestion data for model verification, the ADM1 digestion model was extended to incorporate the valeric acid dynamics and acetic acid inhibition (Li, Yang, Liu, Ma, & Wang, 2019).…”