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Zhou Y, Huang X, Ma S, He J. Thermo-alkaline pretreatment of excess sludge: Effects of temperature on volatile fatty acids accumulation and microbial community. J Environ Manage 2023; 342:118244. [PMID: 37269730 DOI: 10.1016/j.jenvman.2023.118244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 06/05/2023]
Abstract
In order to explore the role of thermal-alkaline pretreatment temperatures (TAPT) in sludge fermentation and the microbial characteristics, five groups (100, 120, 140, 160 °C and control group) were set up and the results showed that the increasing TAPT promoted the dissolution of soluble chemical oxygen demand (SCOD) and VFAs, but had slight influence on the release of NH4+-N and PO43--P. What's more, when it was 120 °C, the SCOD dissolution was comparable to that at 160 °C. Overall, 120 °C was the optimal condition, corresponding to the fact that the maximum release of SCOD was 8788.74 mg/L (2.63 times of the control group), the maximum dissolution of VFAs was 4596 mg/L (about 1.28 times of the control group). The trend of C/N was not significant. High-throughput sequencing showed that Firmicutes and Actinobacteriota were enriched with the temperature increasing, while Proteobacteria and Chloroflexi did not change significantly. Firmicutes was in a stable dominant position. Temperature conditions brought about significant changes in microbial interspecific interaction. Carbohydrate and amino acids had the highest metabolic abundance, especially at 120 °C group. The change rule of amino acid metabolism was similar to that of lipid metabolism, and the abundance of energy metabolism gradually increased with temperature. The protein metabolism was greatly affected by temperature. This study revealed the effect of microbial mechanism of TAPT on the sludge acid production efficiency.
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Affiliation(s)
- Yuqi Zhou
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Xiao Huang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - Silan Ma
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Jianghao He
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
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Liu Q, Li C, Fan J, Peng Y, Du R. Evaluation of sludge anaerobic fermentation driving partial denitrification capability: In view of kinetics and metagenomic mechanisms. Sci Total Environ 2023; 884:163581. [PMID: 37086990 DOI: 10.1016/j.scitotenv.2023.163581] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/30/2023] [Accepted: 04/15/2023] [Indexed: 05/03/2023]
Abstract
Partial denitrification (PD) provides a promising approach of efficient and stable nitrite (NO2--N) generation for annamox. In this study, the feasibility of short-term sludge anaerobic fermentation driving PD was evaluated. It was found that a higher NO2--N accumulation in nitrate (NO3--N) reduction was obtained with the 5-days fermented sludge compared to 8 and 15-days fermentation. Moreover, compared to acetate as carbon source, sludge fermentation products (SFPs) induced the higher NO2--N production with nitrate-to-nitrite transformation ratio (NTR) nearly 100 %. Denitrification activity of fermented sludge were obviously improved with SFPs as electron donor. Metagenomic analysis revealed that Thauera was the dominant bacteria, which was assumed to be the key contributor to PD performance by harboring the highest narGHI and napAB but much lower nirS and nirK. Under the conditions of SFPs and fermented sludge, Thauera was speculated to have higher resistance than other denitrifiers attributed to versatile carbon metabolic capabilities utilizing SFPs with the significantly improved genes for metabolism of complex organic carbon via glycolysis after anaerobic fermentation. A novel integration of sludge fermentation driving PD and anammox for mainstream wastewater treatment and sidestream polishing was proposed to offer a promising application with reduced commercial carbon source consumption and waste sludge reduction.
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Affiliation(s)
- Qingtao Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Cong Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jiarui Fan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Rui Du
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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Du R, Li C, Liu Q, Fan J, Peng Y. A review of enhanced municipal wastewater treatment through energy savings and carbon recovery to reduce discharge and CO 2 footprint. Bioresour Technol 2022; 364:128135. [PMID: 36257527 DOI: 10.1016/j.biortech.2022.128135] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/08/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Municipal wastewater treatment that mainly performed by conventional activated sludge (CAS) process faces the challenge of intensive aeration-associated energy consumption for oxidation of organics and ammonium, contributing to significant directly/indirectly greenhouse gas (GHG) emissions from energy use, which hinders the achievement of carbon neutral, the top priority mission in the coming decades to cope with the global climate change. Therefore, this article aimed to offer a comprehensive analysis of recently developed biological treatment processes with the focus on reducing discharge and CO2 footprint. The biotechnologies including "Zero Carbon", "Low Carbon", "Carbon Capture and Utilization" are discussed, it suggested that, by integrating these processes with energy-saving and carbon recovery, the challenges faced in current wastewater treatment plants can be overcome, and a carbon-neutral even be possible. Future research should investigate the integration of these methods and improve anammox contribution as well as minimize organics lost under different scales.
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Affiliation(s)
- Rui Du
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Cong Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qingtao Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jiarui Fan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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Zhang Q, Fang S, Cheng X, Wang F, Zhang L, Huang W, Du W, Fang F, Cao J, Luo J. Persulfate-based strategy for promoted acesulfame removal during sludge anaerobic fermentation: Combined chemical and biological effects. J Hazard Mater 2022; 434:128922. [PMID: 35452991 DOI: 10.1016/j.jhazmat.2022.128922] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/28/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
The acesulfame (ACE) degradation in waste activated sludge (WAS) via direct anaerobic fermentation is difficult and the efficient elimination techniques are imperative for the ultimate safe WAS disposal. Persulfate (PS)-based approach was developed to promote the ACE removal during WAS anaerobic fermentation. Results demonstrated the effectiveness of PS-based treatments on ACE degradation, and the ACE removal efficiency was respectively 48.2% and 96.2% in the PS and PS/Fe-treated reactors while it was only 6.0% in the control reactor. Mechanism explorations revealed that the active free radicals (i.e. OH• and SO4•-) generated in the PS-based reactors were the key oxidative species for the ACE degradation. However, such effects were interfered by the released soluble substrates (i.e. protein, carbohydrate and inorganic ions) during anaerobic fermentation by competing and/or quenching free radicals, which caused the deceleration of the ACE removal efficiency. Moreover, the PS-based treatment facilitated the enrichment of functional microorganisms (i.e. Phyllobacteriaceae and Bradyrhizobiaceae) and upregulated the critical genes (i.e. pncB and nadE) involved in the ACE degradation. Based on the density functional theory (DFT) and metabolic intermediates analysis, the hydroxylation and oxidative ring-opening were the two main proposed metabolic pathways for ACE degradation. Overall, the combined chemical and biological metabolism effects collectively contributed to the efficient ACE degradation, and it provided a novel and effective strategy for refractory pollutants removal during WAS anaerobic fermentation.
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Affiliation(s)
- Qin Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Shiyu Fang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Xiaoshi Cheng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Feng Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Le Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Wenxuan Huang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Wei Du
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Fang Fang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Jiashun Cao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Jingyang Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China; Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse, China.
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Zhang L, Deng F, Liu Z, Ai L. Removal of ammonia nitrogen and phosphorus by biochar prepared from sludge residue after rusty scrap iron and reduced iron powder enhanced fermentation. Journal of Environmental Management 2021; 282:111970. [PMID: 33450434 DOI: 10.1016/j.jenvman.2021.111970] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/23/2020] [Accepted: 01/06/2021] [Indexed: 06/12/2023]
Abstract
The rusty scrap iron (RSI) or a mixture of rusty scrap iron and reduced iron powder (RSI-RIP) can be used as an exogenous additive to enhance the anaerobic fermentation of sewage sludge. In order to make rational use of the fermentation residue, the sludge after intensified fermentation was pyrolyzed to produce biochar in this study, which was used in the adsorption of ammonia and phosphorus from the anaerobic fermentation broth. The experimental results demonstrated that the pore structure of the sludge biochar was greatly improved after enhanced fermentation with RSI and RIP. Meanwhile, there was an increase in the proportion of metallic elements such as Ca, Fe and Mg. On the other hand, the RSI-RIP co-enhanced fermented biochar (ES600) prepared at 600 °C showed a higher adsorption capacity, which was comparable to the commercially activated carbon. Neutral or weakly alkaline environments were preferred during the adsorption process. At a suitable pH condition, the maximum removal efficiency of ammonia nitrogen (NH4+-N) and total phosphorus (TP) on ES600 reached 91.3% and 98.6%, respectively. In addition, the saturated ES600 was regenerated by simple washing with ammonia-free water. After three cycles, the removal efficiency of NH4+-N and TP remained at 71.3% and 83.2%, respectively. As a result, the biochar prepared from RSI-RIP enhanced fermented sludge can be used as a promising low-cost adsorbent.
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Affiliation(s)
- Lu Zhang
- Environmental Science and Engineering College, Nanjing Tech University, Nanjing, 211816, China
| | - Feng Deng
- Environmental Science and Engineering College, Nanjing Tech University, Nanjing, 211816, China.
| | - Zhongkai Liu
- Environmental Science and Engineering College, Nanjing Tech University, Nanjing, 211816, China
| | - Lexian Ai
- Environmental Science and Engineering College, Nanjing Tech University, Nanjing, 211816, China
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