在间接热干燥过程中,脱水废水污泥的粘附行为
Junyeong Yoo1, Kazuyuki Oshita1, Taketoshi Kusakabe2
1Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Cluster C, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto, 615-8540, Japan.
Journal of environmental management
|April 5, 2025
概括
在热干燥过程中,泥的附着性随着温度的升高和可溶性细胞外聚合物质 (S-EPS) 的增加而增加. 随着S-EPS度的下降,粘度会增加,这表明热能转化有机物质,增强粘度. 降低温度或减少S-EPS可以减轻这种情况.
科学领域:
- 环境工程 环境工程
- 废物管理 废物管理
- 材料科学 是一种材料科学.
背景情况:
- 在热干燥过程中粘附的泥会带来操作上的挑战.
- 了解影响污泥粘性的因素对于高效的干燥过程至关重要.
研究的目的:
- 调查影响污泥在间接热干燥过程中粘附的因素.
- 分析污泥特性,细胞外聚合物质 (EPS) 和粘附之间的相关性.
- 确定减轻污泥粘附的策略.
主要方法:
- 用皮和剪切测试评估了泥的特性和粘附性.
- 在100°C至180°C的温度下进行热干燥.
- 在干燥过程中监测可溶性EPS (S-EPS) 度的变化.
主要成果:
- 随着干燥温度的提高和初始S-EPS度 (R > 0.88) 的增加,泥的粘合性增加.
- 最初的S-EPS度增加,然后在干燥过程中减少,更高的初始度在早期释放更多的S-EPS.
- 在S-EPS度开始下降后,泥粘附度增加.
结论:
- 污泥粘附受有机物热引起的转变的影响,而不是直接由S-EPS水平影响.
- 通过无氧消化降低干燥温度或降低初始S-EPS度,可以减轻污泥粘附.
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