| Title: | Enhancing the quantity and quality of short-chain fatty acids production from waste activated sludge using CaO2 as an additive |
| Author(s): | Li Y; Wang J; Zhang A; Wang L; |
| Address: | "State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: liyongmei@tongji.edu.cn. State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: wangmumu01@163.com" |
| DOI: | 10.1016/j.watres.2015.06.021 |
| ISSN/ISBN: | 1879-2448 (Electronic) 0043-1354 (Linking) |
| Abstract: | "The effect of calcium peroxide (CaO2) addition on anaerobic fermentation of waste activated sludge (WAS) was investigated. The lab-scale experiments were conducted at 35 degrees C with CaO2 doses ranging from 0.05 to 0.3 g/g VSS. The performances of hydrolysis and acidification of WAS were significantly enhanced by CaO2 addition, whereas the production of methane was inhibited. Maximum total short-chain fatty acids (TSCFA) production (284 mg COD/g VSS) occurred at a CaO2 dose of 0.2 g/g VSS and fermentation time of 7 d, which was 3.9 times higher than the control tests. Further, CaO2 addition led to the conversion of other SCFAs to acetic acid. Acetic acid comprised 60.2% of TSCFA with the addition of 0.2 g CaO2/g VSS compared with 45.1% in the control tests. The mechanism of improved SCFAs generation was analyzed from the view of both chemical and biological effects. Chemical effect facilitated the disintegration of WAS, and improved the activities of both hydrolytic enzymes and acid-forming enzymes. Illumina MiSeq sequencing analysis revealed that bacteria within phylum Firmicutes increased significantly due to CaO2 addition, which played an important role in the hydrolysis and acidification of WAS. In addition, CaO2 oxidized most refractory organic contaminants, which were difficult to biodegrade under the ordinary anaerobic condition. Hydroxyl radicals were the most abundant reactive oxygen species released by CaO2, which played a key role in the removal of refractory organic compounds. We developed a promising technology to produce a valuable carbon source from WAS" |
| Keywords: | "Anaerobiosis Archaea/genetics/metabolism Bacteria/genetics/metabolism Fatty Acids, Volatile/*metabolism Fermentation Molecular Sequence Data Peroxides/*metabolism Sequence Analysis, DNA Sewage/*chemistry Waste Disposal, Fluid/*methods Water Pollutants, Ch;" |
| Notes: | "MedlineLi, Yongmei Wang, Jie Zhang, Ai Wang, Lin eng Research Support, Non-U.S. Gov't England 2015/07/05 Water Res. 2015 Oct 15; 83:84-93. doi: 10.1016/j.watres.2015.06.021. Epub 2015 Jun 17" |
