Dynamic modeling of biological methanation for different reactor configurations: An extension of the anaerobic digestion model No. 1

In biological methanation, the methane produced by anaerobic digestion (AD) is upgraded with the addition of syngas. Several mathematical models have been developed to represent the AD process. However, the modeling of biomethanation is still under development. In this work, an extension of the anaerobic digestion model (ADM1_ME) was proposed to describe the dynamics of biomethanation. The model considered the addition of syngas flow rate (H2/CO) and the adaptation of the volumetric mass transfer coefficient for two different reactor configurations: bubble column reactor and continuous stirred tank reactor operating at mesophilic and ther-mophilic conditions. A sensitivity analysis using the Sobol' and Morris methods was performed for this model, where 14 parameters were selected for model calibration. Simulation results showed an accurate fit for two experimental operating conditions from literature with a RMSE <5.15. The results showed the feasibility of the ADM1_ME to describe the biomethanation process at different operational conditions and reactor configurations.