Influence of temperature on the hydrolysis, acidogenesis and methanogenesis in mesophilic anaerobic digestion: parameter identification and modeling application

Abstract

The effect of temperature on the kinetic parameters involved in the main reactions of the anaerobic digestion process was studied. Batch tests with starch, glucose and acetic acid as substrates for hydrolysis, acidogenesis and methanogenesis, respectively, were performed in a temperature range between 15 and 45 degrees C. First order kinetics was assumed to determine the hydrolysis rate constant, while Monod and Haldane kinetics were considered for acidogenesis and methanogenesis, respectively. The results obtained showed that the anaerobic process is strongly influenced by temperature, with acidogenesis exerting the highest effect. The Cardinal Temperature Model 1 with an inflection point (CTM1) fitted properly the experimental data in the whole temperature range, except for the maximum degradation rate of acidogenesis. A simple case-study assessing the effect of temperature on an anaerobic CSTR performance indicated that with relatively simple substrates, like starch, the limiting reaction would change depending on temperature. However, when more complex substrates are used (e.g. sewage sludge), the hydrolysis might become more quickly into the limiting step.

Moderate temperature increase leads to disintegration of floating sludge and lower abundance of the filamentous bacterium Microthrix parvicella in anaerobic digesters

“…In contrast to the work of Donoso-Bravo et al (2009), which showed that a temperature increase from 37 °C to 40 °C negatively affected acidogenesis and subsequent methanogenesis, our results indicate that a smooth transition from mesophilic operation at 37 °C to thermophilic operation at 55 °C enables a stable biogas production.…”

Influence of digestion temperature and organic loading rate on the continuous anaerobic treatment of process liquor from hydrothermal carbonization of sewage sludge

“…Hydrolysis constant is of major interest in the context of biogas production as hydrolysis is known to be the speedlimiting step in digesting conventional biomass (Donoso-Bravo et al, 2009). Anaerobic wastewater digestion is rather dominated by methanogenesis as the speed-limiting step as there is nearly no particulate matter that needs to be hydrolyzed prior to methanation (Donoso-Bravo et al, 2009;Wirth and Mumme, 2013).…”

Bioelectrochemical regulation accelerates facultatively syntrophic proteolysis

“…Hydrolysis and methanogenesis are considered to be rate limiting steps in the methane fermentation process (7), and obligatory or facultatively syntrophic associations between various bacteria and archaea are reported to be involved in the methanogenesis from some compounds (8). This complexity makes it difficult to investigate the factors influencing the microbial consortia in methanogenic environments under bioelectrochemical control.…”