1
|
Li P, Zhang J, Shen Y, Feng X, Jia W, Liu M, Zhao S. Efficient, quick, and low-carbon removal mechanism of microplastics based on integrated gel coagulation-spontaneous flotation process. WATER RESEARCH 2024; 259:121906. [PMID: 38861760 DOI: 10.1016/j.watres.2024.121906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 06/04/2024] [Accepted: 06/06/2024] [Indexed: 06/13/2024]
Abstract
To address the problems of unstable efficiency, long treatment period, and high energy consumption during microplastics (MPs) removal by traditional coagulation-flotation technology, a gel coagulation-spontaneous flotation (GCSF) process is proposed that employs laminarin (LA) as the crosslinker and polyaluminum chloride (PAC)/polyaluminum ferric chloride (PAFC) as the coagulant to remove MPs. Herein, the effects of GCSF chemical conditions on microplastic-humic acid composite pollutants (MP-HAs) removal were investigated, and the removal mechanisms were analyzed through theoretical calculations and floc structure characterization. Results showed that an LA to PAC/PAFC ratio of 2.5:1 achieved the highest removal of HA (86 %) and MPs (93 %-99 %) in short coagulation (< 1 min) and spontaneous flotation (< 9 min) period. PAC-LA exhibited strong removal ability for MP-HAs while PAFC-LA induced fast flotation speed. The peak intensity and peak shift in Fourier-transformed infrared and X-ray photo-electron spectra indicated that the removal mechanisms of MPs include hydrogen bond adsorption and the sweeping effect, mainly relying on -OH/-C = O on the MPs surface and entrapment of gel flocs with a high degree of aggregation, respectively. The extended Derjaguin-Landau-Verwey-Overbeek calculation also revealed that interactions between PAC/PAFC-LA and MP-HAs were mainly polar interaction (hydrogen bonding) and intermolecular attraction interaction (Lifshitz-van der Waals force), and the sweep effect was reflected by intermolecular interaction. In addition, density function theory calculations indicated that -OH in LA mainly adsorbs DO through a double hydrogen bond configuration, and the crosslinking ligand FeO6/AlO6 assists in DO absorption by -OH.
Collapse
Affiliation(s)
- Panpan Li
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China
| | - Jianguo Zhang
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China
| | - Yongheng Shen
- Department of Life Science, Imperial College London, Silwood Park Campus, Berks SL5 7PY, United Kingdom
| | - Xuefei Feng
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China
| | - Wenlin Jia
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China
| | - Mingkai Liu
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China
| | - Shuang Zhao
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221110, China.
| |
Collapse
|
2
|
Dong P, Li J, Woldeyohans AM, Parmentier D, Van Hulle SWH. Coagulation in combination with anaerobic digestion for enhancement of resource recovery from faecal sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120902. [PMID: 38657411 DOI: 10.1016/j.jenvman.2024.120902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 03/28/2024] [Accepted: 04/10/2024] [Indexed: 04/26/2024]
Abstract
Poorly managed faecal sludge (FS) poses significant challenges to public health and the environment. Anaerobic digestion (AD) of FS provides an effective method for energy recovery while reducing FS associated threats. Recognizing the critical role of the dewatering process before AD, this study investigates the synergistic application of chemical coagulation and mesophilic AD for synthetic FS treatment. FeCl3, AlCl3, Fe2(SO4)3, poly ferric sulfate (PFS) and poly aluminium ferric chloride (PAFC) were utilized at varying dosages to examine their impact on FS properties and subsequent biogas production from the dewatered FS. It was found that coagulation enhances sedimentation efficiencies and dewaterability through mechanisms such as charge neutralization, charge patching and bridging, thereby improving the FS feasibility for AD. Notably, polymer coagulant PFS showed good performance in balancing pollutant removal and methane recovery, contributing to facilitating the hydrolysis and acidogenesis microorganisms involved in the AD process. Optimal dosage was identified at 150 mg/g TS (1.7 g/L FS), achieving prominent removal efficiencies for total COD (67%), turbidity (85%), and total phosphorus (60%), while simultaneously enhancing AD performance with specific CH4 production reaching 517 ml CH₄/g VS or 24.8 ml CH₄/g AD wet feedstock compared to 309 ml CH₄/g VS or 2.7 ml CH₄/g AD wet feedstock in untreated FS.
Collapse
Affiliation(s)
- Pengyu Dong
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint Martens-Latemlaan 2B, Kortrijk, B-8500, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Belgium.
| | - Jin Li
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint Martens-Latemlaan 2B, Kortrijk, B-8500, Belgium; School of Human Settlement and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shannxi Province, 710049, PR China
| | - Akalu M Woldeyohans
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint Martens-Latemlaan 2B, Kortrijk, B-8500, Belgium
| | - Dries Parmentier
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint Martens-Latemlaan 2B, Kortrijk, B-8500, Belgium; Noah Water Solutions Bvba, Burchtweg 7, B-9890, Gavere, Belgium
| | - Stijn W H Van Hulle
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Ghent University Campus Kortrijk, Sint Martens-Latemlaan 2B, Kortrijk, B-8500, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Belgium
| |
Collapse
|
3
|
Mandal P, Gupta AK, Dubey BK. Simultaneous ammonia and organics degradation from municipal landfill leachate by electrochemical oxidation. ENVIRONMENTAL TECHNOLOGY 2024:1-15. [PMID: 38471068 DOI: 10.1080/09593330.2024.2323554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 02/20/2024] [Indexed: 03/14/2024]
Abstract
The two primary issues for wide implementation of the electrochemical oxidation of wastewater are the significant cost of electrode and high energy consumption. On the other side, conventional biological processes and membrane technology have several drawbacks for recalcitrant landfill leachate (LL) treatment. To address these issues, graphite/PbO2 anode was used to treat medium to mature age (biodegradability index, 5-day biochemical oxygen demand/chemical oxygen demand: 0.25) LL. To reduce the cost of the oxidation process and maximize the efficiency, operating conditions were optimized. The optimum parameter values were obtained as 24.7 mA cm-2, 180 ± 3 rpm, and 1.9 cm of current density, stirring rate, and electrode gap, respectively. Dissolved organic carbon (DOC), chemical oxygen demand (COD), and ammonia-N removal efficiencies of 55 ± 1.4%, 81 ± 1.9%, and 56 ± 3% were obtained after 8 h of degradation at optimum conditions. The decrease in aromatic substances and ultraviolet (UV) quenching materials were evaluated by UV-Visible spectroscopy and Specific UV absorbance. The conversion of aromatic compounds into simpler molecule compounds was also verified by Fourier-transform infrared spectroscopy analysis. The lab-scale anode synthesis cost was evaluated as 0.42 USD.
Collapse
Affiliation(s)
- Pubali Mandal
- Department of Civil Engineering, Birla Institute of Technology and Science-Pilani, Pilani, India
| | - Ashok K Gupta
- Environmental Engineering Division, Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Brajesh K Dubey
- Environmental Engineering Division, Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, India
| |
Collapse
|
4
|
Chen H, Xu H, Zhong C, Liu M, Yang L, He J, Sun Y, Zhao C, Wang D. Treatment of landfill leachate by coagulation: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169294. [PMID: 38110093 DOI: 10.1016/j.scitotenv.2023.169294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/06/2023] [Accepted: 12/09/2023] [Indexed: 12/20/2023]
Abstract
Landfill leachate is a seriously polluted and hazardous liquid, which contains a high concentration of refractory organics, ammonia nitrogen, heavy metals, inorganic salts, and various suspended solids. The favorable disposal of landfill leachate has always been a hot and challenging issue in wastewater treatment. As one of the best available technologies for landfill leachate disposal, coagulation has been studied extensively. However, there is an absence of a systematic review regarding coagulation in landfill leachate treatment. In this paper, a review focusing on the characteristics, mechanisms, and application of coagulation in landfill leachate treatment was provided. Different coagulants and factors influencing the coagulation effect were synthetically summarized. The performance of coagulation coupled with other processes and their complementary advantages were elucidated. Additionally, the economic analysis conducted in this study suggests the cost-effectiveness of the coagulation process. Based on previous studies, challenges and perspectives met by landfill leachate coagulation treatment were also put forward. Overall, this review will provide a reference for the coagulation treatment of landfill leachate and promote the development of efficient and eco-friendly leachate treatment technology.
Collapse
Affiliation(s)
- Hongni Chen
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Hui Xu
- Guangxi Key Laboratory of Advanced Structural Materials and Carbon Neutralization, School of Materials and Environment, Guangxi Minzu University, Nanning 530006, China
| | - Chao Zhong
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Mingjie Liu
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Liwei Yang
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Jiaojie He
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Yan Sun
- School of Civil Engineering, Chang'an University, Xi'an 710061, China
| | - Chuanliang Zhao
- School of Civil Engineering, Chang'an University, Xi'an 710061, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Dongsheng Wang
- College of Environmental and Resource Science, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
5
|
Li J, Wang L, Lu J, Peng W, Chen J, Jiang G, Liu D. Treatment of landfill leachate nanofiltration concentrate by a three-dimensional electrochemical technology with waste aluminum scraps as particle electrodes: Efficacy, mechanisms, and enhancement effect of subsequent electrocoagulation. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 173:118-130. [PMID: 37989011 DOI: 10.1016/j.wasman.2023.11.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/24/2023] [Accepted: 11/13/2023] [Indexed: 11/23/2023]
Abstract
Landfill leachate nanofiltration concentrate is a kind of wastewater containing high concentrations of color and refractory organics. Herein, we proposed a novel three-dimensional electrochemical technology (3DET) with waste aluminum scraps as particle electrodes for its treatment. The planar and particle electrodes were first optimized. Ti/RuO2 and graphite were used as anodes in the two-dimensional electrochemical technology (2DET). In the light of contaminant removal (color, UV254, COD, and TOC), chlorine reduction, and energy consumption, graphite was selected as planar anodes and cathodes. Moreover, 3DET with Al particle electrodes (Al 3DET) outperformed that with conventional granular activated carbon electrodes, 2DET, and Al particles. At 120 min, the removal efficiencies of color, UV254, COD, and TOC using Al 3DET were 98.94 %, 84.72 %, 51.93 %, and 67.46 %, respectively. UV-vis and EEM spectroscopy, and GC-MS analyses indicate that macromolecular organic matter such as humic-like substances could be effectively degraded and simultaneously removed. Reactive species identification tests including free radical quenching and EPR spectra were conducted. The results indicate that in addition to anodic direct oxidation, indirect oxidation by oxidative species (H2O2, •OH, and RCS) and flocculation by Al species also played a vital role in contaminant removal. Continuous-flow experiments show that Fe EC as a post-treatment step of Al 3DET could effectively provide a neutralization effect for the 3DET effluent and enhance the removal efficiency of contaminants. The total operating cost of combined process was 1.307 USD/m3. This study shows that the Al 3DET-Fe EC process is a promising technology for the treatment of nanofiltration concentrate.
Collapse
Affiliation(s)
- Jie Li
- School of Economics and Management, Yantai University, Yantai 264005, Shandong Province, China
| | - Lei Wang
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong Province, China
| | - Jianbo Lu
- School of Civil Engineering, Yantai University, Yantai 264005, Shandong Province, China.
| | - Wuliang Peng
- School of Economics and Management, Yantai University, Yantai 264005, Shandong Province, China
| | - Jing Chen
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, Shandong Province, China
| | - Guangming Jiang
- School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, Australia
| | - Dongfang Liu
- School of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| |
Collapse
|
6
|
Shen W, Zhang H, Li X, Qi D, Liu R, Kang G, Liu J, Li N, Zhang S, Hu S. Pathogens and antibiotic resistance genes during the landfill leachate treatment process: Occurrence, fate, and impact on groundwater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:165925. [PMID: 37544439 DOI: 10.1016/j.scitotenv.2023.165925] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/08/2023]
Abstract
Landfill leachate is an essential source of pathogens and antibiotic resistance genes (ARGs) in the environment. However, information on the removal behavior of pathogens and ARGs during the leachate treatment and the impact on surrounding groundwater is limited. In this study, we investigated the effects of leachate treatment on the removal of pathogens and ARGs with metagenomic sequencing, as well as the impact of landfill effluent on groundwater. It is shown that the leachate treatment could not completely remove pathogens and ARGs. Twenty-nine additional pathogens and twenty-nine ARGs were newly identified in the landfill effluent. The relative abundance of pathogens and multiple antibiotic resistance genes decreased after ultrafiltration but relative abundance increased after reverse osmosis. In addition, the relative abundances of Acinetobacter baumannii, Erwinia amylovora, Escherichia coli, Fusarium graminearum, Klebsiella pneumoniae, and Magnaporthe oryzae, as well as mdtH, VanZ, and blaOXA-53 increased significantly in the landfill effluent compared to the untreated leachate. The relative abundance of some mobile genetic elements (tniA, tniB, tnpA, istA, IS91) in leachate also increased after ultrafiltration and reverse osmosis. The size of pathogens, the size and properties of ARGs and mobile genetic elements, and the materials of ultrafiltration and reverse osmosis membranes may affect the removal effect of pathogens, ARGs and mobile genetic elements in leachate treatment process. Interestingly, the pathogens and ARGs in landfill effluent were transferred to groundwater according to SourceTracker. The ARGs, mobile genetic elements, and pathogens that are difficult to remove in the leachate treatment process, provide a reference for optimizing the leachate treatment process and improving the control of pathogens and ARGs. Furthermore, this study clarifies the effect of landfill leachate sources of pathogens and ARGs in groundwater.
Collapse
Affiliation(s)
- Weitao Shen
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Houhu Zhang
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China
| | - Xuejian Li
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China; Department of Engineering, China Pharmaceutical University, Nanjing 211198, China
| | - Dan Qi
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China
| | - Ran Liu
- Key Laboratory of Environment Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Guodong Kang
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China
| | - Jinglong Liu
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China
| | - Nan Li
- Zhongda Hospital Southeast University, Nanjing 210009, China
| | - Shenghu Zhang
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China.
| | - Shuangqing Hu
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai Academy of Environment Sciences, Shanghai 200233, China.
| |
Collapse
|