University of Michigan, Department of Chemical Engineering, Ann Arbor, Michigan 48109-2136, USA.
Phys Chem Chem Phys. 2012 Mar 7;14(9):3140-7. doi: 10.1039/c2cp23792j. Epub 2012 Jan 30.
The article reports the first quantitative kinetics model for supercritical water gasification (SCWG) of real biomass (algae) that describes the formation of the individual gaseous products. The phenomenological model is based on a set of reaction pathways that includes two types of compounds being intermediate between the algal biomass and the final gaseous products. To best correlate the experimental gas yields obtained at 450, 500 and 550 °C, the model allowed one type of intermediate to react to gases more quickly than the other type of intermediate. The model parameters indicate that gas yields increase with temperature because higher temperatures favor production of the more easily gasified intermediate and the production of gas at the expense of char. The model can accurately predict the qualitative influence of the biomass loading and water density on the gas yields. Sensitivity analysis and reaction rate analysis indicate that steam reforming of intermediates is an important source of H(2), whereas direct decomposition of the intermediate species is the main source of CO, CO(2) and CH(4).
这篇文章报道了首个用于描述各气态产物形成过程的真实生物质（藻类）超临界水气化（SCWG）的定量动力学模型。该唯象模型基于一组反应途径，其中包含两种介于藻类生物质和最终气态产物之间的中间化合物。为了最佳关联在 450、500 和 550°C 下获得的实验气体产率，模型允许一种中间体比另一种中间体更快地与气体反应。模型参数表明，气体产率随温度升高而增加，因为较高的温度有利于更易气化的中间产物的生成和以气体为代价的焦的生成。该模型可以准确预测生物质负荷和水密度对气体产率的定性影响。敏感性分析和反应速率分析表明，中间体的蒸汽重整是 H(2)的重要来源，而中间物种的直接分解是 CO、CO(2)和 CH(4)的主要来源。
