Abstract In this study, the steady states of an anaerobic digestion model are analytically computed and characterized. The influence of the dilution rate on the system states and methane outflow rate is illustrated by means of one-parameter bifurcation diagrams. A two-parameter bifurcation diagram is also computed. This diagram illustrates the combined effect of the dilution rate and inlet substrate concentration on the system steady states and allows to determine corrective actions (in terms of selecting appropriated inputs) for preserving system stability and efficiency. Expressions for all the boundaries and critical points appearing in the diagram are provided. Furthermore, the complex system behavior is illustrated by means of phase portraits. The paper emphasizes the methodology, which can also be applied to other bioprocesses taking place in continuously stirred tank reactors. The method allows practitioners to build two-parameter bifurcation diagrams by solving a set of algebraic equations. This implies low computational requirements.

中文翻译：

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一种评估厌氧消化系统稳定性的建设性方法

摘要 在这项研究中，对厌氧消化模型的稳态进行了分析计算和表征。稀释率对系统状态和甲烷流出率的影响通过单参数分叉图来说明。还计算了一个二参数分岔图。该图说明了稀释率和入口底物浓度对系统稳态的综合影响，并允许确定纠正措施（在选择适当的输入方面）以保持系统稳定性和效率。提供了图中出现的所有边界和临界点的表达式。此外，复杂的系统行为通过相图来说明。论文强调方法论，这也可以应用于在连续搅拌釜反应器中进行的其他生物过程。该方法允许从业者通过求解一组代数方程来构建双参数分岔图。这意味着低计算要求。