缓解N的缓解 N的缓解
Kyeong Hwan Kang1, Minseok Yang2, Shahbaz Raza1
1Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul, 04763, Republic of Korea.
Chemosphere
|June 3, 2023
概括
从发酵的污水污泥中添加碳来源显著减少了垃圾填埋场液的氧化 (N2O) 排放. 这种方法增强了脱化,在废水处理中有效减轻N2O气体 (N2O(g)).
科学领域:
- 环境工程 环境工程
- 微生物学 微生物学
- 废物管理 废物管理
背景情况:
- 垃圾填埋场液由于含有化合物和潜在的N2O排放,造成环境风险.
- 强化脱需要外部碳源 (C源) 才能有效地去除酸盐.
- 无氧发酵的污水污泥可以作为可持续的C来源.
研究的目的:
- 调查无氧发酵污水污泥作为外部C源的有效性,以减轻垃圾填埋污水中的N2O排放.
- 优化无氧污泥发酵条件,以最大限度地提高VFA的产量.
- 评估这种C源对脱率和N2O减少的影响.
主要方法:
- 污水污泥经历了热友性无氧发酵,有机载荷率 (OLR) 增加.
- 根据水解效率,sCOD和VFA度确定了最佳发酵条件.
- 污泥发酵酸 (SF) 被用作垃圾填埋液 (LL) 的脱测试中的C来源,测量酸盐去除和N2O排放.
主要成果:
- 最佳发酵发生在OLR为40.48g的COD/L·d,产生高的水解效率和VFA度.
- 与原始LL相比,SF添加显著增加了5.42倍的特定酸盐去除率 (KNR).
- 添加SF减少了N2O气体排放量的1.72倍,并证明了6.70 mg N/g VSS小时的特定N2O减排率 (KN2O).
结论:
- 无氧发酵的污水污泥是有效的外部C来源,可以增强脱和减轻垃圾填埋污水中的N2O排放.
- 该研究表明,在生物垃圾填埋场污水处理中,同时减少酸盐和N2O的可行策略.
- 利用发酵有机废物提供了一种可持续的方法来管理废水处理厂的N2O排放.
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