8 results on '"Jiashun Cao"'
Search Results
2. New insights into different surfactants’ impacts on sludge fermentation: Focusing on the particular metabolic processes and microbial genetic traits
- Author
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Jingyang Luo, Shiyu Fang, Wenxuan Huang, Feng Wang, Le Zhang, Fang Fang, Jiashun Cao, Yang Wu, and Dongbo Wang
- Subjects
General Environmental Science - Published
- 2021
- Full Text
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3. Degradation of cefradine in alga-containing water environment: a mechanism and kinetic study
- Author
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Zhilin Zhao, Ruixue Jiang, Jiaqin Wang, Jiayu Sun, Jiashun Cao, Yaru Wei, Xiaochen Li, and Yifei Liu
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Ultraviolet Rays ,Health, Toxicology and Mutagenesis ,Kinetics ,010501 environmental sciences ,01 natural sciences ,Hydrolysis ,Adsorption ,Cefradine ,Desorption ,Microalgae ,medicine ,Water environment ,Environmental Chemistry ,Photodegradation ,0105 earth and related environmental sciences ,Cephradine ,Photolysis ,Chemistry ,Water ,General Medicine ,Pollution ,Anti-Bacterial Agents ,Biodegradation, Environmental ,Chemical engineering ,Degradation (geology) ,Chlamydomonas reinhardtii ,Water Pollutants, Chemical ,medicine.drug - Abstract
Large quantities of antibiotics are manufactured, used, and eventually discharged into alga-containing water environment as prototypes, by-products, or transformation products. Different activities of Chlamydomonas reinhardtii toward cefradine (CFD) were studied, and the results indicated that CFD is resistant (removal rate of 5.45–14.72%) in simulated natural water environment. Cefradine was mainly removed by hydrolysis, adsorption, desorption, photodecarboxylation, and photoisomerization. The effects of C. reinhardtii density, initial solution pH, and different light sources on CFD removal efficiency were investigated. The optimum conditions occurred at a density of algae 10 × 104 cells/mL, a solution pH of 9.0, and the ultraviolet (UV) light. Additionally, the removal kinetics under 16 different conditions was explored. The results showed that the removal of CFD fits well with a pseudo-first-order kinetic, and the half-life times are from 0.8 to 261.6 days. This study summarizes the CFD removal mechanisms in alga-containing water environment, highlights the important role played by light irradiation in eliminating CFD, and obtains the important kinetic data on CFD removal.
- Published
- 2019
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4. Coagulation- and Adsorption-Based Environmental Impact Assessment and Textile Effluent Treatment
- Author
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Haroon Rashid, Muhammad Aleem, Muhammad Waqar Akram, Muhammad Abbas, Jiashun Cao, Yang Wu, Chao Li, and Muhammad Nawaz
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Environmental Engineering ,Alum ,Ecological Modeling ,Chemical oxygen demand ,010501 environmental sciences ,Total dissolved solids ,Pulp and paper industry ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,Wastewater ,chemistry ,medicine ,Environmental Chemistry ,Environmental science ,Sewage treatment ,Effluent ,0105 earth and related environmental sciences ,Water Science and Technology ,Activated carbon ,medicine.drug ,Total suspended solids - Abstract
Disposal of industrial effluents (especially the textile industry) into the drains without prior treatment is a common practice that affects aquatic life and pollutes the soil and groundwater quality. Textile effluents contain organic and inorganic pollutants in terms of high pH, suspended and dissolved solids, chemical oxygen demand, heavy metals, and many other contaminants. Therefore, it is obligatory to dispose off wastewater according to environmental standards. The present study is planned to determine textile wastewater characteristics and recommend efficient and economical treatment options. Wastewater samples from three different industries were collected and analyzed. Nine different treatments using different dosages of alum, activated carbon, and their mixture were used to investigate treatment performance. Analysis of variance and correlation was used to optimize the results. A highly significant correlation was found among the treatments ranging from 92 to 100% for observed parameters. pH, chemical oxygen demand, and total suspended solids were removed significantly. A combination of alum and activated carbon found to be the most efficient treatment. Based on the highly significant results among different parameters, a combined wastewater treatment plant is recommended for a cluster of industrial units.
- Published
- 2020
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5. Catalytic Degradation of Humic Acid by Mn-Cu/Al-MCM-41 Catalyst in Electro-Fenton/Chlorine Processes: Influencing Factors, Mechanisms, and Kinetics
- Author
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Hailing Meng, Zailiang Liu, Liu Tinglei, Chao Li, Yaohui Lv, and Jiashun Cao
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inorganic chemicals ,chemistry.chemical_classification ,Environmental Engineering ,Chemistry ,Ecological Modeling ,Kinetics ,Oxide ,chemistry.chemical_element ,010501 environmental sciences ,01 natural sciences ,Pollution ,Catalysis ,chemistry.chemical_compound ,MCM-41 ,Chlorine ,Environmental Chemistry ,Humic acid ,Leaching (metallurgy) ,Bimetallic strip ,0105 earth and related environmental sciences ,Water Science and Technology ,Nuclear chemistry - Abstract
Degradation of humic acid (HA) in heterogeneous electro-Fenton/chlorine processes was investigated using a catalyst of Mn-Cu bimetallic oxides supported on Al-containing MCM-41. The catalyst was synthesized by co-precipitation method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption–desorption, and X-ray photoelectron spectroscopy (XPS) techniques. The bimetallic oxide catalyst exhibited a higher activity compared to monometallic one. Adding Al in the bimetallic oxide catalyst enhanced the stability of the catalyst, reduced metal ion leaching, increased the initial ratio of Mn3+/Mn4+ and Cu+/Cu2+, and slightly enhanced the degradation efficiency of HA and corresponding chemical oxygen demand (COD). The effect of Mn and Cu content in MCM-41, catalyst dosage, pH value, and initial concentration of HA and salinity on degradation efficiency were investigated. A high COD reduction about 91.5% and general current efficiency (GCE) about 41.7% have been achieved under the optimal conditions of pH 6, salinity 1000 mg/L, catalyst dosage 0.5 g/L, HA sodium salt concentration 200 mg/L, and reaction time 60 min. A possible mechanism for the reaction was suggested. Kinetic analysis showed that HA degradation in the electro-Fenton/chlorine processes was fit with first-order kinetics.
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- 2019
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6. Achieving low effluent NO3-N and TN concentrations in low influent chemical oxygen demand (COD) to total Kjeldahl nitrogen (TKN) ratio without using external carbon source
- Author
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Zhaoxia Xue, Oloche James Oleyiblo, Y. Martins Otache, Qian Feng, and Jiashun Cao
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Anaerobic digestion ,Denitrification ,Activated sludge ,Chemistry ,Environmental chemistry ,Chemical oxygen demand ,Sewage treatment ,Oceanography ,Effluent ,Kjeldahl method ,Anoxic waters ,Water Science and Technology - Abstract
Two mathematical models were used to optimize the performance of a full-scale biological nutrient removal (BNR) activated treatment plant, a plug-flow bioreactors operated in a 3-stage phoredox process configuration, anaerobic anoxic oxic (A2/O). The ASM2d implemented on the platform of WEST2011 software and the BioWin activated sludge/anaerobic digestion (AS/AD) models were used in this study with the aim of consistently achieving the designed effluent criteria at a low operational cost. Four ASM2d parameters (the reduction factor for denitrification \((\eta _{NO_3 H} )\), the maximum growth rate of heterotrophs (µH), the rate constant for stored polyphosphates in PAOs (qpp), and the hydrolysis rate constant (kh)) were adjusted. Whereas three BioWin parameters (aerobic decay rate (bH), heterotrophic dissolved oxygen (DO) half saturation (KOA), and YP/acetic) were adjusted. Calibration of the two models was successful; both models have average relative deviations (ARD) less than 10% for all the output variables. Low effluent concentrations of nitrate nitrogen (N-NO3), total nitrogen (TN), and total phosphorus (TP) were achieved in a full-scale BNR treatment plant having low influent chemical oxygen demand (COD) to total Kjeldahl nitrogen (TKN) ratio (COD/TKN). The effluent total nitrogen and nitrate nitrogen concentrations were improved by 50% and energy consumption was reduced by approximately 25%, which was accomplished by converting the two-pass aerobic compartment of the plug-flow bioreactor to anoxic reactors and being operated in an alternating mode. Findings in this work are helpful in improving the operation of wastewater treatment plant while eliminating the cost of external carbon source and reducing energy consumption.
- Published
- 2015
- Full Text
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7. Pilot-scale study on nitrogen and aromatic compounds removal in printing and dyeing wastewater by reinforced hydrolysis-denitrification coupling process and its microbial community analysis
- Author
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Hongqiang Ren, Yi Li, Jiashun Cao, Chao Li, Tang Siyuan, and Erqin Yin
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Denitrification ,Nitrogen ,Health, Toxicology and Mutagenesis ,chemistry.chemical_element ,Pilot Projects ,Real-Time Polymerase Chain Reaction ,Hydrocarbons, Aromatic ,Waste Disposal, Fluid ,Denitrifying bacteria ,Bioreactors ,Bioreactor ,Environmental Chemistry ,Organic chemistry ,Coloring Agents ,Effluent ,Pollutant ,Denaturing Gradient Gel Electrophoresis ,Chemistry ,Hydrolysis ,General Medicine ,Pulp and paper industry ,Pollution ,Biodegradation, Environmental ,Microbial population biology ,Printing ,Sewage treatment ,Water Pollutants, Chemical - Abstract
Aiming to efficiently dispose printing and dyeing wastewater with “high organic nitrogen and aromatic compounds, but low carbon source quality”, the reinforced anaerobic hydrolysis-denitrification coupling process, based on improved UASB reactors and segregated collection-disposition strategy, was designed and applied at the pilot scale. Results showed that the coupling process displayed efficient removal for these two kinds of pollutants (nitrogen and aromatics), since the concentration of NH3-N (shortened as ρ (NH3-N)) < 8 mg/L, ρ (TN) < 15 mg/L with long-term stability for the effluent, and both species and abundances of aromatics reduced greatly by UASBs according to GC-MS. Microbial community analysis by PCR-DGGE showed that Bacteroidetes and Alphaproteobacteria were the dominant communities in the bioreactors and some kinds of VFAs-producing, denitrifying and aromatic ring opening microorganisms were discovered. Further, the nirK and bcrA genes quantification also indicated the coupling process owned outstanding denitrification and aromatic compound-degrading potential, which demonstrates that the coupling process owns admirable applicability for this kind of wastewater treatment.
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- 2015
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8. Evaluation and improvement of wastewater treatment plant performance using BioWin
- Author
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Jiashun Cao, Zhaoxia Xue, Fang Fang, Qian Feng, Gan Wang, and Oloche James Oleyiblo
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Phosphorus ,chemistry.chemical_element ,Activated sludge model ,Oceanography ,Pulp and paper industry ,Clarifier ,Activated sludge ,chemistry ,Yield (chemistry) ,Environmental science ,Sewage treatment ,Aeration ,Effluent ,Water Science and Technology - Abstract
In this study, the activated sludge model implemented in the BioWin® software was validated against full-scale wastewater treatment plant data. Only two stoichiometric parameters (Yp/acetic and the heterotrophic yield (YH)) required calibration. The value 0.42 was used for Yp/acetic in this study, while the default value of the BioWin® software is 0.49, making it comparable with the default values of the corresponding parameter (yield of phosphorus release to substrate uptake \((Y_{PO_4 } )\)) used in ASM2, ASM2d, and ASM3P, respectively. Three scenarios were evaluated to improve the performance of the wastewater treatment plant, the possibility of wasting sludge from either the aeration tank or the secondary clarifier, the construction of a new oxidation ditch, and the construction of an equalization tank. The results suggest that construction of a new oxidation ditch or an equalization tank for the wastewater treatment plant is not necessary. However, sludge should be wasted from the aeration tank during wet weather to reduce the solids loading of the clarifiers and avoid effluent violations. Therefore, it is recommended that the design of wastewater treatment plants (WWTPs) should include flexibility to operate the plants in various modes. This is helpful in selection of the appropriate operating mode when necessary, resulting in substantial reductions in operating costs.
- Published
- 2014
- Full Text
- View/download PDF
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