Integrated experimental and techno-economic modeling of renewable natural gas production from prairie biomass

This study coupled experimental and techno-economic modeling to evaluate the economic prospects of utilizing prairie biomass as a feedstock for anaerobic digestion. Anaerobic digestion experiments were performed using 15 lab-scale bioreactors under semi-continuous operation, designed based off a box-Behnken design with three factors. Response variables included biogas and biomethane yields, in addition to numerous digestate physico-chemical characteristics. Statistical models were developed from the experimental data to predict these responses and were subsequently incorporated into a techno-economic model developed in Python using BioSTEAM. In addition to optimizing key anaerobic digestion parameters, four scenarios were evaluated investigating liquid digestate recirculation, as well as methane recovery from the liquid digestate in a two-stage anaerobic digestion process.

本研究耦合实验与技术经济建模手段，评估以草原生物质为原料开展厌氧消化(anaerobic digestion)的经济可行性。研究采用15台实验室规模生物反应器，以半连续运行模式实施厌氧消化实验，实验设计基于三因素Box-Behnken设计(Box-Behnken Design)。响应变量包含沼气与生物甲烷产率，以及沼渣的多项理化特性。研究基于实验数据构建统计模型以预测上述响应变量，随后将其集成至依托Python语言结合BioSTEAM工具开发的技术经济模型中。除优化关键厌氧消化参数外，本研究还评估了四种场景，分别考察液体沼渣回流工艺，以及两级厌氧消化过程中从液体沼渣中回收甲烷的效果。