Modelling of anaerobic digestion of microalgae biomass: Effect of overloading perturbation

Anaerobic digestion (AD) of microalgae is an intriguing approach for bioenergy production. The scaling-up of AD presents a significant challenge due to the systematic efficiency losses related to process instabilities. To gain a comprehensive understanding of AD behavior, this study assessed a modified version of the anaerobic digestion model No1 (ADM1) + Contois kinetics to represent microalgae AD impacted by overloading. To this end, two new inhibition functions were implemented: inhibition by acetate for acidogenesis/acetogenesis and total volatile fatty acids for hydrolysis. This proposed ADM1 modification (including Contois kinetics) simulated AD behavior during the stable, disturbed and recovery periods, showing that the inhibition functions described in the original ADM1 cannot explain the AD performance under one of the most common perturbations at industrial scale (overloading). The findings underscore the importance of refining the inhibitions present in original ADM1 to better capture and predict the complexities of microalgae AD against overloading.微藻厌氧消化（Anaerobic Digestion，AD）是一种颇具研究价值的生物能源生产途径。受工艺不稳定性引发的系统性效率损失制约，AD的规模化放大面临显著挑战。为全面认知AD的运行特性，本研究对厌氧消化模型1号（ADM1）结合康托伊斯动力学（Contois kinetics）的改进版本进行了评估，以表征受超负荷影响的微藻AD过程。为此，研究新增了两类抑制函数：分别用于产酸/产乙酸阶段的乙酸抑制，以及用于水解阶段的总挥发性脂肪酸抑制。该改进后的ADM1方案（含康托伊斯动力学）可模拟稳定、受扰及恢复阶段的AD运行行为，结果表明，原始ADM1中的抑制函数无法解释工业规模下最常见的扰动之一（超负荷）对应的AD运行表现。本研究结果凸显了优化原始ADM1内置抑制机制的必要性，以更精准地捕捉并预测微藻AD在超负荷扰动下的复杂特性。