热水解污泥中的黑色素的表征和对脱水性能的影响
Xiuqin Cao1, Ran He2, Mingyan Jia2
1Key Laboratory of Urban Storm Water System and Water Environment, Ministry of Education, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, 1#Zhanlanguan Road, Xicheng District, Beijing 100044, China.
Environmental research
|October 3, 2023
概括
热水解预处理污泥形成黑色素,阻碍无氧消化. 这项研究描述了黑色素的特征,并表明它们通过改变污泥结构和特性,显著恶化了污泥的脱水能力.
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.
- 水处理 处理水的方法
背景情况:
- 污泥的热水解预处理 (THP) 通过梅拉德反应产生耐火棕色黑色胺素.
- 这些黑色素素对随后的污泥无氧消化 (AD) 和脱水过程产生负面影响.
- 黑胺的特定生成模式和对污泥脱水能力的影响尚不清楚.
研究的目的:
- 开发一种方法来表征和量化在污泥的THP过程中产生的黑色素.
- 调查黑色素素对污泥脱水性能的影响.
- 阐明黑色素因子影响污泥脱水能力的机制.
主要方法:
- 利用三维光区域集成 (3DEEM-FRI) 在污泥中进行黑色素素的表征和半量化.
- 在混合污泥中添加合成黑胺,以评估它们对脱水的影响.
- 分析了污泥表面粘度,一致系数 (k),流动行为指数 (n) 和泽塔潜力的变化.
主要成果:
- 3DEEM-FRI有效地区分了黑胺与其他有机污泥成分.
- 黑胺显著降低了污泥的脱水能力,过蛋糕固体含量在特定的添加水平下降约20%.
- 黑胺增加了污泥的表面粘度和一致性系数 (k),降低了流动行为指数 (n),并削弱了流动性.
结论:
- 黑胺复杂化了污泥的内部结构,增加了粘度,并阻碍了脱水.
- 黑色素素捕获水分子,减少粒子大小和泽塔电位,增强静电排斥,并抑制花.
- 这些影响共同导致污泥脱水性能显著恶化.
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