ZHANG Yan-ping,HU Rui-qi,LI Yi-bing,et al.Lysis and Reduction of Excess Sludge by Ferrate Oxidation[J].China Water & Wastewater,2020,36(15 15):59-64.
Lysis and Reduction of Excess Sludge by Ferrate Oxidation
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
15 15
Page:
59-64
Column:
Date of publication:
2020-08-01
- Keywords:
- ferrate; excess sludge; oxidation; sludge reduction
- Abstract:
- Ferrate was used to oxidize excess sludge to realize reduction. The sludge was oxidized quickly by the ferrate, and intermediate oxides were formed during the reaction. After reaction of 5 min, MLVSS and VSS/SS decreased rapidly, which indicated that EPS and sludge cells were oxidized and cracked， and the internal substances were released. This caused the remarkable increase of TPN, SPN, polysaccharide, SCOD, TN and TP. With the increase of reaction time, SCOD and polysaccharide increased slowly, and TPN, SPN, TN and TP eventually tended to be stable. This was due to the fact that Fe(Ⅵ) and its intermediate oxides could further react with the intracellular dissolution substances. At the same time, the oxidants were gradually consumed over time. According to UV-visible scanning spectrogram results, the sludge cells could be further oxidized to smaller molecules organic matters, which resulted in the absorbance values significantly increased in the ultraviolet region. Microscopic examination showed that ferrate gradually destroyed the structure of sludge floc during the oxidization process. It led to naked cells, which were then oxidized and broken.
Last Update:
2020-08-01