Publications by authors named "Chengran Fang"

19 Publications

  • Page 1 of 1

Effect of air and water on the release of chlorine from semi-aerobic landfill.

Environ Technol 2021 Jan 10:1-10. Epub 2021 Jan 10.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, People's Republic of China.

Landfill leachate has a high chloride (Cl) content. Because it is highly mobile, and cannot be sorbed or transformed bio-chemically, it is important to have detailed information about how it migrates in landfill sites. In this study, we set up four lab-scale simulated landfills, including an anaerobic landfill (AL), an anaerobic landfill with leachate recirculation (RAL), an anaerobic/semi-anaerobic landfill with leachate recirculation (RASL), and an anaerobic/semi-aerobic landfill (ASL), to explore how, when regulated, moisture and air affected the migration of chlorine. We found that water and air had a strong influence on the release of Cl. Leachate obviously promoted Cl dissolution in refuse when recirculated. When air was introduced into landfill, thereby changing it from anaerobic to semi-aerobic, the leachate Cl concentration increased sharply from around 4-9 g L (RASL) and 18 g L (ASL), respectively. In principle, Cl is released continuously when leachate is recirculated in landfills (RAL and RASL), but it can also be found a terminal when the leachate recirculation stops (AL and ASL). Cumulative amounts of 64, 66, 27, and 53 g of Cl were released from the AL, RAL, RASL, and ASL, respectively. Lower COD/Cl and -N/Cl ratios in ASL and RASL after day 175 indicated that lower Cl pollution risk than that in AL and RAL.
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http://dx.doi.org/10.1080/09593330.2020.1869838DOI Listing
January 2021

Arsenic transformation behavior mediated by arsenic functional genes in landfills.

J Hazard Mater 2021 Feb 14;403:123687. Epub 2020 Aug 14.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, 310023, China.

Landfill arsenic pollution is a complicated problem because of the sophisticated species and transformation of fractions involved. This study investigated arsenic transformation behavior from the viewpoint of arsenic functional genes based on analysis of 29 aged refuse samples collected from 11 sanitary landfills in 10 cities in Zhejiang Province, China. Arsenic species distribution varied significantly with landfill process. Landfill contains rich arsenic resistant microbes. arrA genes were the key factor responsible for arsenic transformation and migration in landfill. Although the abundance of aioA genes was the lowest among the four tested arsenic functional genes, it was the second important genes for arsenic distribution. Microbial metabolic activity was the main cause of arsenic transformation, and arsenate reduction by microbes was a key driver of arsenic mobilization in landfills. Moreover, arsenate was reduced to arsenite and further methylated to monomethylarsine (MMA) and dimethylarsine (DMA), decreasing the total arsenic content during the landfill process, but also inducing a new risk because of the arsenic effluent will be more easily as the state of arsenite, MMA, and DMA in the liquid phase. Overall, this study provides a picture of arsenic species transformation and insight into key roles involved in arsenic pollution during landfill processes.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123687DOI Listing
February 2021

Effect of substrate sulfur state on MM and DMS emissions in landfill.

Waste Manag 2020 Oct 12;116:112-119. Epub 2020 Aug 12.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China; Instrumental Analysis Center of Zhejiang Gongshang University, Hangzhou 310018, China. Electronic address:

Methyl mercaptan (MM) and dimethyl sulfide (DMS) are typical landfill odorous gases that have received little attention compared with hydrogen sulfide (HS). In this study, landfill MM and DMS emissions were investigated regarding their origin from substrates with different sulfur states, namely, intrinsic organic sulfur and external inorganic sulfur (SO). Substrates with high protein contents showed the highest potential for MM and DMS emissions, at 46.0 and 9.2 μL·g substrate, respectively. Meanwhile, a comparable contribution by SO was achieved when the SO content comprised over 40% of the substrate. The substrate contribution to DMS emission was up to 10 times the SO contribution. Meanwhile, the SO contribution to MM emission was over 1000 times that to DMS emissions. MM and DMS can accumulate in landfill sites and then be transformed into HS or sulfide (S). This research offers a comprehensive understanding of MM and DMS emissions in landfill and provides a basis for classification management methods in landfill sites.
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http://dx.doi.org/10.1016/j.wasman.2020.08.005DOI Listing
October 2020

Performance, mechanism and stability of nitrogen-doped sewage sludge based activated carbon supported magnetite in anaerobic degradation of coal gasification wastewater.

Sci Total Environ 2020 Oct 17;737:140285. Epub 2020 Jun 17.

Rural Ecological and Energy Station of Zhejiang Province, Hangzhou 310012, China.

In current study, the UASB reactor was enhanced by nitrogen-doped sewage sludge based activated carbon supported FeO (FeO/N-SBAC) for coal gasification wastewater treatment. The results showed that COD removal efficiency was increased to 64.4% with FeO/N-SBAC assistance and the corresponding methane production rate achieved up to 1093.6 mL/d. FeO/N-SBAC promoted microbial growth and enzymatic activity, leading to high extracellular polymeric substances and coenzyme F concentrations. FeO/N-SBAC also facilitated the sludge granulation process with high particle size, substantial interspecific signal molecules and low diffusible signal factor. Microbial community analysis revealed that FeO/N-SBAC might support direct interspecies electron transfer process, in which the enriched Geobacter was likely to communicate with Methanothrix via electrical connection, improving anaerobic degradation of coal gasification wastewater. Total phenols shock and pH impact revealed that reactor stability was enhanced in the FeO/N-SBAC-supplemented system.
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http://dx.doi.org/10.1016/j.scitotenv.2020.140285DOI Listing
October 2020

Diffusion MRI simulation of realistic neurons with SpinDoctor and the Neuron Module.

Neuroimage 2020 11 27;222:117198. Epub 2020 Jul 27.

INRIA Saclay, Equipe DEFI, CMAP, Ecole Polytechnique, 91128 Palaiseau Cedex, France. Electronic address:

The diffusion MRI signal arising from neurons can be numerically simulated by solving the Bloch-Torrey partial differential equation. In this paper we present the Neuron Module that we implemented within the Matlab-based diffusion MRI simulation toolbox SpinDoctor. SpinDoctor uses finite element discretization and adaptive time integration to solve the Bloch-Torrey partial differential equation for general diffusion-encoding sequences, at multiple b-values and in multiple diffusion directions. In order to facilitate the diffusion MRI simulation of realistic neurons by the research community, we constructed finite element meshes for a group of 36 pyramidal neurons and a group of 29 spindle neurons whose morphological descriptions were found in the publicly available neuron repository NeuroMorpho.Org. These finite elements meshes range from having 15,163 nodes to 622,553 nodes. We also broke the neurons into the soma and dendrite branches and created finite elements meshes for these cell components. Through the Neuron Module, these neuron and cell components finite element meshes can be seamlessly coupled with the functionalities of SpinDoctor to provide the diffusion MRI signal attributable to spins inside neurons. We make these meshes and the source code of the Neuron Module available to the public as an open-source package. To illustrate some potential uses of the Neuron Module, we show numerical examples of the simulated diffusion MRI signals in multiple diffusion directions from whole neurons as well as from the soma and dendrite branches, and include a comparison of the high b-value behavior between dendrite branches and whole neurons. In addition, we demonstrate that the neuron meshes can be used to perform Monte-Carlo diffusion MRI simulations as well. We show that at equivalent accuracy, if only one gradient direction needs to be simulated, SpinDoctor is faster than a GPU implementation of Monte-Carlo, but if many gradient directions need to be simulated, there is a break-even point when the GPU implementation of Monte-Carlo becomes faster than SpinDoctor. Furthermore, we numerically compute the eigenfunctions and the eigenvalues of the Bloch-Torrey and the Laplace operators on the neuron geometries using a finite elements discretization, in order to give guidance in the choice of the space and time discretization parameters for both finite elements and Monte-Carlo approaches. Finally, we perform a statistical study on the set of 65 neurons to test some candidate biomakers that can potentially indicate the soma size. This preliminary study exemplifies the possible research that can be conducted using the Neuron Module.
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http://dx.doi.org/10.1016/j.neuroimage.2020.117198DOI Listing
November 2020

Antibiotics in Leachates from Landfills in Northern Zhejiang Province, China.

Bull Environ Contam Toxicol 2020 Jul 29;105(1):36-40. Epub 2020 May 29.

Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, 310023, China.

The concentrations and distributions of five sulfonamide, three tetracycline, and two macrolide antibiotics in leachates from three landfill sites in northern Zhejiang Province, China, were determined by solid-phase extraction and ultra-high performance liquid chromatography mass spectrometry. Most of the antibiotics were detected in the leachate samples. The concentrations and distributions of the antibiotics in leachates of different ages were very different. The total sulfonamide, tetracycline, and macrolide concentrations in the leachates ranged from not detected to 1.57 × 103, not detected to 5.19 × 103, and 7.30 to 5.42 × 102 ng/L, respectively. The total concentrations of detectable antibiotics were higher in fresh leachates than aged and middle-aged leachates. Higher TC-group concentrations were found in the leachates than have been found in previously published studies of landfill leachates in China. The results improve our understanding of and ability to manage antibiotic residues in landfills.
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http://dx.doi.org/10.1007/s00128-020-02894-xDOI Listing
July 2020

Sulfate reduction behavior in the leachate saturated zone of landfill sites.

Sci Total Environ 2020 Aug 25;730:138946. Epub 2020 Apr 25.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China. Electronic address:

Municipal solid waste landfills are considered one of the most important parts of the sulfur cycle. However, few studies have focused on sulfate reduction in the leachate saturated zone, where the temperature may be variable. In this work, the sulfate reduction behavior was evaluated in a landfill leachate saturated zone under temperatures between 30 and 80 °C. The results show that microbial sulfate reduction is high in the saturated zone, especially when the temperature is at 50-60 °C. The microbial diversity and the abundance of functional genes results reveal that specific sulfate-reducing bacteria such as Dethiobacter, the bacteria that offer energy to them, and genes other than dsrA and dsrB may have a close relationship with the variation in the reduction of sulfate. This work may improve the knowledge of sulfate reduction in the landfill sites and therefore offer theoretical support to management strategies.
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http://dx.doi.org/10.1016/j.scitotenv.2020.138946DOI Listing
August 2020

Effects of di-n-butyl phthalate and di-2-ethylhexyl phthalate on pollutant removal and microbial community during wastewater treatment.

Ecotoxicol Environ Saf 2020 Jul 27;198:110665. Epub 2020 Apr 27.

Zhejiang Gongshang University, School of Food Science and Biotechnology, Hangzhou, 310018, China.

Due to the wide use of plastic products and the releasability of plasticizer into surrounding environment, the hazards, residues and effects of phthalic acid esters (PAEs) in ecosystems have been paid more and more attention. Little information is available about the effects of PAEs on the normal wastewater treatment, although the distribution of PAEs in soil and other ecosystems is closely related to the discharge of sewage. In this study, the effects of high concentrations of di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) on pollutant removal and the microbial community during landfill leachate treatment was investigated. After domestication, the activated sludge was used in the co-treatment of landfill leachate and simulated domestic wastewater. We verified that this process reduced the toxicity of landfill leachate. However, high concentrations of added DBP and DEHP were removed first, while the removal of these pollutants from raw landfill leachate was limited. The results of high-throughput sequencing revealed that the bacterial diversity was diminished and the microbial community structure was significantly affected by the addition of DBP and DEHP. The DBP and DEHP samples had 79.05% and 82.25% operational taxonomic units (OTU), respectively, in common with the raw activated sludge. Many genera of PAE-degrading bacteria that had no significant evolutionary relationship were found in the raw activated sludge. And the widespread presence of PAE-degrading bacteria could effectively keep the concentrations of PAEs low during the wastewater treatment.
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http://dx.doi.org/10.1016/j.ecoenv.2020.110665DOI Listing
July 2020

Effective degradation of Di-n-butyl phthalate by reusable, magnetic FeO nanoparticle-immobilized Pseudomonas sp. W1 and its application in simulation.

Chemosphere 2020 Jul 25;250:126339. Epub 2020 Feb 25.

Zhejiang Gongshang University, School of Food Science and Biotechnology, Hangzhou 310018, China.

Di-n-butyl phthalate (DBP), one of the most widely used plasticizers, has been listed as a priority pollutant because of its toxicity to both humans and animals. In this study, Pseudomonas sp. W1, isolated from activated sludge, was capable of degrading 99.88% of DBP (1000 mg L) within 8 days. We immobilized the W1 strain using FeO iron nanoparticles (IONPs) coated with poly-dopamine (PDA), and further evaluated its DBP degradation efficiency. The DBP degradation performance of W1 was improved by immobilization, exhibiting 99.69% of DBP degradation efficiency on the 6th day, which was 25.68% higher than un-immobilized W1. After three cycles of magnetic recycling and utilization, W1-PDA-IONPs retained 99.6% of their original efficiency. W1-PDA-IONPs were then used to degrade DBP in landfill leachate. When the proportion of raw leachate was ≤50%, DBP could be all degraded by W1-PDA-IONPs within 6 days. In 100% landfill leachate, DBP degradation efficiency after 10 days of incubation reached 66.40%. Furthermore, W1-PDA-IONPs cells in a simulated aeration system could be effectively magnetically separated at aeration rates from 60 to 600 mL min. These results highlight the potential of W1-PDA-IONPs in the bioremediation of DBP-contaminated waste water.
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http://dx.doi.org/10.1016/j.chemosphere.2020.126339DOI Listing
July 2020

Enhanced 2,4,6-trichlorophenol anaerobic degradation by FeO supported on water hyacinth biochar for triggering direct interspecies electron transfer and its use in coal gasification wastewater treatment.

Bioresour Technol 2020 Jan 21;296:122306. Epub 2019 Oct 21.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou 310023, China.

FeO supported on water hyacinth biochar (FeO/WHB) was successfully used in anaerobic degradation of 2,4,6-trichlorophenol and coal gasification wastewater (CGW). Chemical oxygen demand removal efficiency and methane production were significantly improved to 98.9% and 2.0 L with FeO/WHB assisted. FeO/WHB facilitated the conversion of CO to methane and reduce H production. A higher coenzyme F concentration of 1.32 μmol/(g-mixed liquor volatile suspended solids) was found with the presence of FeO/WHB, which might result in a faster conversion of acetate to methane. More interspecific signal molecules, lower diffusible signal factor, and higher mean particle size indicated that FeO/WHB accelerated the sludge granulation process. Microbial community analysis revealed that enriched bacteria Geobacter along with archaea Methanothrix and Methanosarcina may be involved in direct interspecies electron transfer by FeO/WHB stimulation, enhancing the performance of 2,4,6-trichlorophenol fermentation. It is shown that use of FeO/WHB is feasible for enhanced CGW treatment.
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http://dx.doi.org/10.1016/j.biortech.2019.122306DOI Listing
January 2020

Fate and migration of arsenic in large-scale anaerobic landfill.

Waste Manag 2019 Mar 26;87:559-564. Epub 2019 Feb 26.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou 310023, China.

The fate and migration of arsenic in a large-scale anaerobic landfill site was investigated by characterization of the total As content and its speciation using a sequential extraction procedure. The total As content in the anaerobic landfill varied greatly with age of the deposited refuse, ranging from 15.26 ± 4.18 mg kg to 38.41 ± 10.41 mg kg. There was an increasing trend from the upper layer to a depth of 18-19 m, followed by a decrease in the lower layer. Sequential extraction results showed that As present in exchangeable and weak-acid soluble forms (F1) varied from 0.08 ± 0.01 mg kg to 12.61 ± 0.92 mg kg, but from 1.28 ± 0.11 mg kg to 8.40 ± 0.23 mg kg in reducible forms (F2). Oxidizable (F3) and residual (F4) forms of As, which were much more stable and for which the environmental risk correspondingly decreased, accounted for 24.21%-58.70% and 10.11%-30.90% of the total As content, respectively. Nitrate and carbonate had a strong influence on the distribution of As in F1 species; ferric ion affected As distribution in F2; both ferrous ion and dissolved oxygen content contributed to F3 distribution; As in F4 was associated with crystalline minerals structures and was only weakly affected by environmental factors. The deposition process could be divided into six phases to interpret As migration and distribution within the anaerobic landfill after closure.
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http://dx.doi.org/10.1016/j.wasman.2019.02.046DOI Listing
March 2019

Sulfate reduction at micro-aerobic solid-liquid interface in landfill.

Sci Total Environ 2019 Jun 20;667:545-551. Epub 2019 Feb 20.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China.

HS can be produced under aerobic conditions, which goes against the traditional view of an obligatory anaerobic metabolism process. In this research, the sulfate-reduction behavior at the micro-aerobic solid-liquid interface in a landfill was investigated. HS emission from mineralized waste from the landfill material could be enhanced when exposed to O. The highest HS concentration of 56.54 mg·m, observed at an O concentration of 2%, was 4.5 times higher than the highest concentration of HS recorded under anaerobic conditions. The presence of leachate influenced protection of the anaerobic sulfate-reducing bacteria against O, allowing the bacteria to survive and even undergo significant sulfate reduction under micro-aerobic conditions. The sulfate concentration could be maintained at a high level because of possible oxidation-reduction cycling under micro-aerobic conditions and the risk of HS emission was always high. This research provides a theoretical basis for controlling the release of HS within landfills.
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http://dx.doi.org/10.1016/j.scitotenv.2019.02.275DOI Listing
June 2019

Potential enhancement of direct interspecies electron transfer for anaerobic degradation of coal gasification wastewater using up-flow anaerobic sludge blanket (UASB) with nitrogen doped sewage sludge carbon assisted.

Bioresour Technol 2018 Dec 4;270:230-235. Epub 2018 Sep 4.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou 310023, China.

Waste sewage sludge was converted into the novel conductive material of nitrogen doped sewage sludge carbon (N-SC) to enhance anaerobic degradation of coal gasification wastewater (CGW). The results indicated that N-SC played a significant role in enhanced efficiencies, with chemical oxygen demand (COD) removal efficiency increased by 25.4%, methane production rate improved by 68.1% and total volatile fatty acids (VFA) decreased by 37.5% than that of controlled reactor. The conductivity, activity of electron transport, and extracellular polymeric substances (EPS) of anaerobic sludge were remarkably enhanced with N-SC, which promoted sludge granulation and supplied better conductive environment for microorganisms. The microbial community analysis revealed that potential enhancement of direct interspecies electron transfer (DIET) was achieved by electrical connection between enriched Geobacter, Pseudomonas and Methanosaeta with N-SC assisted, which enhanced the anaerobic degradation of CGW. Moreover, anaerobic degradation with N-SC had higher capacity to resist acidic shocks, facilitating the process stability.
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http://dx.doi.org/10.1016/j.biortech.2018.09.012DOI Listing
December 2018

Waste rice straw and coal fly ash composite as a novel sustainable catalytic particle electrode for strengthening oxidation of azo dyes containing wastewater in electro-Fenton process.

Environ Sci Pollut Res Int 2017 Dec 30;24(35):27136-27144. Epub 2017 Sep 30.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, 310023, China.

A novel catalytic particle electrode (CPE) was synthesized from waste rice straw and coal fly ash which was employed to strengthen electro-Fenton treating actual azo dyes containing wastewater. Results showed that the prepared CPE exhibited excellent electro-catalytic activity and significantly improved performance of pollutants removal at near-neutral pH condition, achieving over 73.5 and 90.5% of chemical oxygen demand (COD) and color removal percentages, respectively, allowing discharge criteria to be met. And the electro-Fenton with CPE improved the biodegradability of wastewater in terms of BOD/COD, resazurin dehydrogenase activity, and toxicity, indicating the potential application of integrated biosystem for this type of wastewater. On the basis of inhibition of different radical scavengers and fluorescence test, it was deduced that the main contribution of the novel CPE was responsible for catalyzing electro-generate HO to produce more hydroxyl radicals in electro-Fenton, and the positive role of generation of superoxide anion at near-neutral pH was also proved, further the possible reaction mechanism was proposed. Moreover, CPE showed the advantages of superior stability and low cost at successive runs and the results offered new insights for sustainable use of waste materials.
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http://dx.doi.org/10.1007/s11356-017-0319-1DOI Listing
December 2017

Sorption of tetracycline on biochar derived from rice straw under different temperatures.

PLoS One 2017 8;12(8):e0182776. Epub 2017 Aug 8.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, Zhejiang, China.

Biochars produced from the pyrolysis of waste biomass under limited oxygen conditions could serve as adsorbents in environmental remediation processes. Biochar samples derived from rice straw that were pyrolyzed at 300 (R300), 500 (R500) and 700°C (R700) were used as adsorbents to remove tetracycline from an aqueous solution. Both the Langmuir and Freundlich models fitted the adsorption data well (R2 > 0.919). The adsorption capacity increased with pyrolysis temperature. The R500 and R700 samples exhibited relative high removal efficiencies across a range of initial tetracycline concentrations (0.5mg/L-32mg/L) with the maximum (92.8%-96.7%) found for adsorption on R700 at 35°C. The relatively high surface area of the R700 sample and π-π electron-donor acceptor contributed to the high adsorption capacities. A thermodynamic analysis indicated that the tetracycline adsorption process was spontaneous and endothermic. The pH of solution was also found to influence the adsorption processes; the maximum adsorption capacity occurred at a pH of 5.5. These experimental results highlight that biochar derived from rice straw is a promising candidate for low-cost removal of tetracycline from water.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0182776PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5549735PMC
October 2017

Dimethyl sulfide emission behavior from landfill site with air and water control.

Biodegradation 2017 12 3;28(5-6):327-335. Epub 2017 Jul 3.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China.

Municipal solid waste landfills are responsible for odors affecting the environment and human health. Dimethyl sulfide (DMS) is one of the major odorous compounds known for its low odor threshold and wide distribution. This study examined the generation, migration and emission of DMS in four artificial landfill-simulating reactors: Reactor 1 and Reactor 2, running under anaerobic and semi-aerobic conditions, respectively, without leachate recirculation; and Reactor 3 and Reactor 4, running under anaerobic and semi-aerobic conditions, respectively, with leachate recirculation. From the odor control perspective, aeration can efficiently inhibit maximum DMS headspace concentration by 31.7-93.7%, especially with the functioning of leachate recirculation. However, leachate recirculation in anaerobic conditions may double the DMS emission concentration but may also shorten the period over which DMS is effective because of the upward migration of liquid DMS in the recirculated leachate. The DMS generation was active in the acidification and methane fermentation phase of the simulated landfill and was possibly affected by the volatile fatty acid concentration, chemical oxygen demand, total organic carbon concentration and pH of the leachate, as well as total organic carbon in the refuse. Most significantly, DMS emission can be effectually dealt with by aeration along with leachate recirculation.
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http://dx.doi.org/10.1007/s10532-017-9799-4DOI Listing
December 2017

Occurrence of Veterinary Antibiotics in Swine Manure from Large-scale Feedlots in Zhejiang Province, China.

Bull Environ Contam Toxicol 2017 Apr 27;98(4):472-477. Epub 2017 Feb 27.

Key Laboratory of Recycling and Eco-treatment of Waste Biomass of Zhejiang Province, Zhejiang University of Science and Technology, Hangzhou, 310023, China.

The occurrence and distribution of five sulfonamides and three tetracyclines in swine manure sampled from large-scale feedlots in different areas of Zhejiang Province, China were detected using solid-phase extraction and high-performance liquid chromatography. All eight test antibiotics were detected in most of the manure samples. The dominant antibiotics in swine manure were sulfadiazine, sulfamerazine, sulfadimidine, tetracycline, and chlortetracycline. The maximum concentration of residual antibiotic reached up to 57.95 mg/kg (chlortetracycline). The concentrations and distribution of both types of antibiotics in swine manure of different areas varied greatly. Relatively higher concentrations of sulfonamides were found in swine manure from the Zhejiang area in this experiment compared with previous studies. The results revealed that antibiotics were extensively used in feedlots in this district and that animal manure might act as a non-specific source of antibiotic residues in farmlands and aquatic environments.
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http://dx.doi.org/10.1007/s00128-017-2052-3DOI Listing
April 2017

Heavy metals and PCDD/Fs in solid waste incinerator fly ash in Zhejiang province, China: chemical and bio-analytical characterization.

Environ Monit Assess 2012 Jun 19;184(6):3711-20. Epub 2011 Jul 19.

Department of Environmental Engineering, Taizhou College, Linhai 317000, China.

Fly ash samples were taken from solid waste incinerators with different feeding waste, furnace type, and air pollution control device in six cities of Zhejiang province. The solid waste incinerators there constitute one fifth of incinerators in China. Heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in the fly ash. Moreover, the fly ash samples were extracted by toxicity characteristic leaching procedure (TCLP). The biotoxicity of the leachate was evaluated by Chlorella pyrenoidosa. High variation and contents were found for both the heavy metals and PCDD/Fs. The contents of Zn, Cu, As, Pb, Cd, Cr, Ni, and Hg in the fly ash samples varied from 300 to 32,100, 62.1-1175, 1.1-57, 61.6-620, 0.4-223, 16.6-4380, 1.2-94.7, and 0.03-1.4 μg g(-1) dw, respectively. The total contents of 17 PCDD/Fs varied from 0.1128 to 127.7939 μg g(-1) dw, and the 2,3,7,8-TeCDD toxic equivalents (TEQ) of PCDD/Fs ranged from 0.009 to 6.177 μg g(-1) dw. PCDF congeners were the main contributor to the TEQ. The leachate of the fly ash showed biotoxicity to C. pyrenoidosa. A significant correlation was found between the Cd and EC(50) values. Further research is required to investigate the environmental impact of the various pollutants in the fly ash.
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http://dx.doi.org/10.1007/s10661-011-2218-0DOI Listing
June 2012

Effects of operational factors on soluble microbial products in a carrier anaerobic baffled reactor treating dilute wastewater.

J Environ Sci (China) 2008 ;20(6):690-5

College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China.

The effects of feed strength, hydraulic residence time (HRT), and operational temperatures on soluble microbial product (SMP) production were investigated, to gain insights into the production mechanism. A carrier anaerobic baffled reactor (CABR) treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9-18 h, and temperatures of 10-28 degrees C. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature (28 degrees C), SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10 degrees C, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand (SCOD) ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.
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http://dx.doi.org/10.1016/s1001-0742(08)62114-2DOI Listing
December 2008