污泥细胞外聚合物质的水友性/疏水性特征与污泥在热压干燥中保持水分的能力之间的关系
Dexiao Ma1, Shuo Cheng2, Yulin Zhang1
1School of Environmental Science & Technology, Dalian University of Technology, Dalian, 116024 Liaoning, China.
The Science of the total environment
|January 21, 2024
概括
热压泥干燥通过影响细胞外聚合物物质 (EPS) 来降低保持水分的能力. 机械压缩和热能加速水分释放,主要来自细胞内和EPS结合的来源.
科学领域:
- 环境科学 环境科学
- 化学工程是化学工程的重要组成部分.
- 材料科学 是一种材料科学.
背景情况:
- 污泥处理带来了环境风险.
- 热压干燥在污泥处理中是有效的,因为它具有快速加热和高干燥率.
- 细胞外聚合物物质 (EPS) 在干燥过程中污泥保持水分的能力中的作用尚未得到充分研究.
研究的目的:
- 调查EPS水友性/疏水性特征与污泥保持水分的能力之间的关系.
- 分析干燥时间和机械压缩对污泥湿度的影响.
- 为了阐明在热压泥干燥过程中释放水分的机制.
主要方法:
- 使用热压干燥的泥处理,使用不同的干燥时间和机械压缩.
- 用于EPS分析的XAD树脂分化.
- 热力学分析水分吸附异热,异热热和差异.
主要成果:
- 增加的干燥时间和机械压缩降低了污泥的保持水分的能力.
- 机械压缩 (25 kPa) 在相同的干燥时间内,污泥温度增加了16%,蛋白质含量增加了13.8%.
- 托芬蛋白样物质是EPS中主要的水友性/疏水性有机物质.
结论:
- 热压干燥,加快温度升高和机械挤压通过破坏微生物和释放水分来降低污泥的保持水分的能力.
- 随着蛋白质含量和水组暴露到85°C,EPS的疏水性增加.
- 在85°C以上,蛋白质分解进一步促进了EPS结合的水分释放,这表明了污泥干燥机制的不同阶段.
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