The nucleation of flocculent sludge as seed in a mesophilic Internal Circulation Anaerobic reactor was investigated with a quantitative method proposed by us in this paper. In the 85th days, the average sludge diameter increased from 47.8 microm to 96.1 microm, which indicated that the nucleation was completed. During this process, the average sludge diameter had a significant linear correlation with the time with coefficient of 0.9893, the increase rate of average sludge diameter was 0.58 microm/d. Nucleus ratio of sludge increased from 7.6% on the 1st day to 36.1% on the 85th day. The increase rate of the nucleus ratio fluctuated in a wide range, experienced 'fast-slow-fast' three stages. During the experiment, the concentration of extra cellular polymers (ECPs) of the sludge was significantly positively correlated with the increase rate of the nucleus ratio, which indicated that ECPs could affect nucleation rate. During nucleation, the bio-activity of the sludge increased, but the improvement of settlement ability was not significant. The above-mentioned quantitative method and results would be useful to understand the sludge granulation mechanism on the level of reactor.
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J Hazard Mater
January 2025
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, PR China. Electronic address:
Copper (Cu)-containing wastewater has proven difficult to effectively treat using the anammox process. In this study, the nitrogen removal efficiency (NRE), sludge characteristics, microbial community and recovery mechanisms of biochar-mediated anammox under Cu stress were elucidated. At a Custress of 5 mg/L, a 73.
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Center for Satellite Application on Environment, Ministry of Ecology and Environment, Beijing 100094, China.
The edge structures of carbonaceous materials exhibit temperature-dependent behavior on the atomic scale, with variations in the relative ratios of zigzag, reconstructed 5-7 zigzag (ZZ57), and armchair edges observed at different temperatures. Nevertheless, the mechanisms underlying the interconversion of these edge structures and the influence of the surrounding metals remain unclear. This study investigates the reconstruction and reversible transformation processes of ZZ57 edge structures in carbon materials and examines the effects of different metal atoms (Na, K, and Ca) by using density functional theory.
View Article and Find Full Text PDFJ Hazard Mater
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Shanxi Key Laboratory of Sorghum Genetic and Germplasm Innovation, Sorghum Research Institute, Shanxi Agricultural University, Jinzhong 030600, China.
The partitioning and migrating of antibiotic residues pose a considerable pollution to the river environment. However, a source-specific approach for quantifying the fate of antibiotics is lacking. To further elucidate the migration behavior of antibiotics from different pollution sources in aquatic environments, we introduced a source-specific partition coefficient (S-Kp) based on Positive Matrix Factorization (PMF) model to improve the multimedia model.
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Sanitary Engineering Laboratory, Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 9 Iroon Polytechniou St., Zographou Campus, 15773, Athens, Greece.
Vertical subsurface flow constructed wetlands (VSSF CWs) were employed to investigate the use of biochar that could be produced with local agricultural biomass through pyrolysis, recycled glass from local recycling companies and gel beads with decreased packing volume and shipping cost as substrate alternatives to sand. The materials were assessed in terms of granulometry, porosity, adsorption capacity and hydraulic conductivity and were used for the treatment of an upflow anaerobic sludge blanket (UASB) reactor, treating domestic wastewater, effluent. Granulometry was a major factor impacting TSS removal that ranged from 81% ± 10% to 97% ± 2%.
View Article and Find Full Text PDFEnviron Res
January 2025
Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, P. R. China; Key Laboratory of Urban Stormwater System and Water Environment (Beijing University of Civil Engineering and Architecture), Ministry of Education, Beijing 100044, P. R. China. Electronic address:
The use of purified hydrocolloids extracted from waste-activated sludge has significant potential for preventing seed deterioration caused by aging. In this study, we compared the advantages and disadvantages of 3 types of purified hydrocolloid seed coatings from different waste sludges and one commercial seed coating at different spraying times (2, 4, 6, and 8). Compared with coated maize seeds, uncoated maize seeds underwent significant functional changes during the aging process according to the infrared spectroscopy results.
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