量化生物质颗粒化对使用单粒子反应器,X射线计算机断层学和计算建模的快速热解的影响
Meagan F Crowley1, Reinhard Seiser1, Mario Alejandro Sánchez Posada2
1National Renewable Energy Laboratory (NREL), Golden, Colorado 15013, United States.
概括
用于快速热解的生物质原料颗粒化显著改变 pore 结构,减缓转化并增加 char. 准确的计算模型必须考虑这些微观结构变化,以优化生物燃料生产.
科学领域:
- 生物质热化学转换生物质的热化学转换.
- 生物燃料的生产生产.
- 基纤维素原料的特性表征
背景情况:
- 基纤维素原料的孔隙结构和密度对于热化学转化过程中的粒子内部运输至关重要.
- 生物质微观结构因物种和预处理技术 (如颗粒化) 而异,影响热解行为.
- 火解过程中的形态变化会影响孔隙结构,转化时间和产品分布.
研究的目的:
- 为了全面比较整洁与颗粒化松原料的快速热解.
- 调查颗粒化对粒子尺度运输现象和转化行为的影响.
- 用实验数据和X射线计算机断层扫描 (XCT) 成像来验证粒子尺度模型.
主要方法:
- 单粒子快速热解实验用整洁和颗粒化松树进行.
- 开发一个粒子尺度模型,包括异性热和质量传输和CRECK机制反应.
- 使用X射线计算机断层扫描 (XCT) 进行定量微观结构分析的3D成像.
主要成果:
- 颗粒化制造出更密集,更不透的松原料,导致较慢的热解和较高的碳产量,与整洁的松相比.
- Pyrolytic 转化增加了碳的多孔性和透性,同时降低了形性和异型性.
- 粒子建模证明了动态,异型运输对于精确的模拟具有至关重要的重要性.
结论:
- 颗粒化在快速热解过程中显著改变了生物质转化行为.
- 微结构属性,特别是孔隙结构和异构性,必须纳入计算模型,以准确设计热解过程.
- 了解这些微结构效应对于优化从纤维纤维素原料中生产生物燃料和生物化学品至关重要.
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