起始pH值在调节污泥无氧发酵中的硫循环动态中的作用
Zirui Liu1, Qizi Fu1, Jiyong Wang1
1College of Environmental Science and Engineering and Key Laboratory of Environmental Biology and Pollution Control (Ministry of Education), Hunan University, Changsha 410082, PR China.
Bioresource technology
|February 16, 2025
概括
最初的pH值在污泥无氧发酵 (AF) 过程中显著影响硫化 (H2S) 的产生. 酸性条件增加H2S,而性条件通过改变硫化合物和微生物活动来减少它.
科学领域:
- 环境微生物学 环境微生物学
- 生物地质化学循环的过程
- 废水处理 废水处理
背景情况:
- 最初的pH值对于污泥无氧发酵 (AF) 是至关重要的,影响短链脂肪酸的产生.
- 在AF期间,初始pH对有毒硫化 (H2S) 生产的影响仍未得到充分研究.
研究的目的:
- 为了研究初始pH对硫化 (H2S) 在污泥无氧发酵 (AF) 过程中产生的影响.
- 阐明将初始pH与H2S生成和厌氧硫循环联系起来的机制.
主要方法:
- 泥无氧发酵 (AF) 实验在不同的初始pH条件下进行 (例如pH7,4,9).
- 测量包括累积的H2S产量,污泥分解,溶解的硫化物和有机硫释放,以及有机硫化合物的结构分析.
- 进行了细胞膜完整性和产生H2S的微生物活动的分析.
主要成果:
- 将初始pH值从7变为4增加了142%的累积H2S产量,而将pH值变为9则降低了45.4%.
- 酸性和性初始pH都促进了污泥的分解和溶解和有机硫化合物的释放.
- 酸性pH改变了蛋白质结构,有利于H2S的产生,但抑制了H2S的产生活动,而性pH促进了硫化金属的形成.
结论:
- 最初的pH值显著影响污泥AF中的H2S产量,因为它会影响污泥的分解,硫的分化和微生物活动.
- 酸性初始pH通过结构变化和改变的硫化物平衡增强H2S释放,而性pH通过金属硫化物沉减轻它.
- 这些发现加深了对污泥处理过程中依赖pH的无氧硫循环的理解.
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