燃烧性城市固体废弃物组件在早期热解阶段的机械强度变化和机制分析
Yifan Jia1,2, Dezhen Chen1,2, Sijia Xu1,2
1Thermal and Environmental Engineering Institute, School of Mechanical Engineering, Tongji University, Shanghai, China.
概括
城市固体废物 (MSW) 碎片化是困难的,因为高抗拉强度. 这项研究分析了温度如何影响早期热解过程中织品,塑料和纸张等可燃MSW组件的断裂强度.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 废物管理 废物管理
背景情况:
- 城市固体废物 (MSW) 的来源隔离有助于回收织品,塑料和纸张等可燃成分.
- 这些材料具有很高的抗拉强度,这给破碎和随后的资源回收带来了挑战.
- 了解早期热解过程中的机械强度变化对于优化碎碎工艺至关重要.
研究的目的:
- 为了研究温度对可燃MSW组件的断裂强度的影响.
- 探索早期热解过程中强度减少的潜在机制.
- 提供基础数据,以改善MSW的破碎和资源回收.
主要方法:
- 使用通用电子测试机器进行机械测试,以确定棉花,PET,象牙板, kraft 纸和羊毛在N2大气下30-250°C的破裂强度.
- 反应力场分子动力学 (ReaxFF-MD) 模拟,分析半纤维素糖群的分解行为和羊毛中的范德瓦尔斯能量变化.
- 棉线束断裂强度与线数量和温度的相关性分析.
主要成果:
- 所有测试的可燃MSW组件的断裂强度随着温度的增加而下降.
- 聚乙烯二甲 (PET) 的强度降低率最高,其次是羊毛和棉花.
- 与棉花相比, kraft 纸和象牙板的强度降低速度较慢.
- 棉花强度的降低与半纤维素分解 (葡萄糖酸) 和CO2释放有关.
- 由于分子链放松,PET强度下降.
- 羊毛强度的降低最初是由于范德瓦尔斯能量的降低,随后是分子链断裂.
结论:
- 在早期热解过程中,温度显著降低了可燃MSW组件的断裂强度.
- 不同的材料表现出不同的强度减弱机制,受其化学成分和结构的影响.
- 材料大小,正如棉花捆的例子所示,也会影响热处理期间的断裂强度变化.
- 这项研究为MSW组件的热力学行为提供了关键的见解,为增强回收和资源回收的策略提供了信息.
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