Publications by authors named "Zishen Mou"

14 Publications

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Synergetic activation of peroxymonosulfate by MnO-loaded β-FeOOH catalyst for enhanced degradation of organic pollutant in water.

Sci Total Environ 2019 Nov 29;693:133589. Epub 2019 Jul 29.

Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130026, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130026, PR China.

In this paper, manganese dioxide (MnO) loaded iron oxyhydroxide (β-FeOOH) was synthesized aiming to improve the catalytic performance of β-FeOOH as peroxymonosulfate activator. The β-FeOOH@MnO/PMS system exhibited excellent performance and its reaction rate constant of Acid Orange 7 (AO7) degradation (0.0533 min) was approximately 2.3 times as that in β-FeOOH/PMS system (0.0232 min). β-FeOOH@MnO possessed superior properties as catalyst than β-FeOOH, owing to the higher surface hydroxyl density with higher specific surface area, redox ability and electronic transmission rate. Moreover, on the basis of the analysis from FTIR and XPS, it was found that the redox reaction of Fe/Fe and Mn/Mn synergistically activated PMS as well as the generation of FeOH and MnOH accelerated activating PMS in the β-FeOOH@MnO/PMS system. Thus, MnO and FeOOH synergistically activated PMS to reactive oxygen species (ROS). And O, O and OH were identified as predominant ROS in the β-FeOOH@MnO/PMS system on the basis of the result from quenching experiments and ESR. As a result, TOC removal rate was increased up to 22.62%. Additionally, β-FeOOH@MnO exhibited good stability with low iron dissolution and manganese dissolution. Generally, this study proposed that β-FeOOH@MnO was an efficient and environmental catalyst as PMS activator for organic pollutant degradation in water.
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http://dx.doi.org/10.1016/j.scitotenv.2019.133589DOI Listing
November 2019

Identification and evaluation of flos introduced to the Hailuogou area based on ITS sequences and active compounds.

PeerJ 2019 3;7:e7636. Epub 2019 Sep 3.

State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution (Chengdu University of Technology), Chengdu, People's Republic of China.

flos (LJF), the dried flower buds of Thunb., have been used in traditional Chinese herbal medicine for thousands of years. Recent studies have reported that LJF has many medicinal properties because of its antioxidative, hypoglycemic, hypolipidemic, anti-allergic, anti-inflammatory, and antibacterial effects. LJF is widely used in China in foods and healthcare products, and is contained in more than 30% of current traditional Chinese medicine prescriptions. Because of this, many Chinese villages cultivate LJF instead of traditional crops due to its high commercial value in the herbal medicine market. Since 2005, the flower buds of are the only original LJF parts considered according to the Chinese Pharmacopoeia of the People's Republic of China. However, for historical and commercial reasons, some closely related species of . continue to be mislabeled and used as LJF. Currently, there are hundreds of commercial varieties of LJF on the market and it is difficult to choose fine LJF varieties to cultivate. In this study, a total of 21 varieties labeled as LJF on the market were planted in the Hailuogou area. In order to choose the optimum variety, internal transcribed spacer (ITS) sequence alignment analysis was used to test whether the 21 varieties were genuine LJF or not. Cluster analysis of active components based on the content of chlorogenic acid and luteoloside in flower buds, stems and leaves was used to evaluate the quality of the varieties. Results demonstrated that four of the varieties were Hand.-Mazz., while the other 17 varieties were , and genuine LJF. The ITS sequence analysis was proven to be highly effective in identifying LJF and flos. Among the 17 varieties, the amounts of chlorogenic acid and luteoloside in flower buds, stems and leaves were significantly different. Based on the cluster analysis method, the variety H11 was observed to have the highest level of active components, and is therefore recommended for large-scale planting in the Hailuogou area.
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http://dx.doi.org/10.7717/peerj.7636DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6730534PMC
September 2019

Characteristics of Inorganic Phosphate-Solubilizing Bacteria from the Sediments of a Eutrophic Lake.

Int J Environ Res Public Health 2019 06 17;16(12). Epub 2019 Jun 17.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.

Inorganic phosphate-solubilizing bacteria (IPB) are an important component of microbial populations in lake sediments. The phosphate that they decompose and release becomes an important source of phosphorus for eutrophic algae. The IPB strains were screened and isolated from the sediments of Sancha Lake using National Botanical Research Institute's phosphate (NBRIP) plates. Their taxonomy was further determined by the 16S rDNA technique. The tricalcium phosphate-solubilizing ability of obtained IPB strains was evaluated using NBRIP- bromophenol blue (BPB) plates and Pikovskaya (PVK) liquid medium. Then, the ability of IPB strains to release phosphorus from the sediments were investigated by mimicking the lake environment. In this study, a total of 43 IPB strains were screened and isolated from the sediments of Sancha Lake, belonging to three phyla, eight families, and ten genera. Among them, two potentially new strains, SWSI1728 and SWSI1734, belonged to genus Bacillus, and a potentially new strain, SWSI1719, belonged to family Micromonosporaceae. Overall, the IBP strains were highly diverse and Bacillus and Paenibacillus were the dominant genera. In the tricalcium phosphate-solubilizing experiment, only 30 of the 43 IPB strains exhibited clear halo zones on plates, while in the liquid culture experiment, all strains were able to dissolve tricalcium phosphate. The phosphate-solubilizing abilities of the strains varied significantly, and the strain SWSI1725 of the genus showed the strongest ability with a phosphate-solubilizing content of 103.57 mg/L. The sterilized systems demonstrated significantly elevated phosphorus hydrochloride (HCl-P) decomposition and release from the sediments after the inoculation of IPB strains, whereas no significant effect was demonstrated on the phosphonium hydroxide (NaOH-P). Thus, the IPB strains in the sediments of Sancha Lake possessed rich diversity and the ability to release phosphorus in sediments.
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http://dx.doi.org/10.3390/ijerph16122141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6617373PMC
June 2019

Rapid Sequestration of Ecosystem Carbon in 30-year Reforestation with Mixed Species in Dry Hot Valley of the Jinsha River.

Int J Environ Res Public Health 2019 05 31;16(11). Epub 2019 May 31.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.

Reforestation plays an important role in the carbon cycle and climate change. However, knowledge of ecosystem carbon sequestration through reforestation with mixed species is limited. Especially in dry hot valley of the Jinsha River, no studies cover total ecosystem carbon sequestration level in mature mixed plantations for a limited area of mixed plantations and difficulty in the sampling of plant roots and deep soil. In this study, carbon sequestration of seven mixed plantations of different ages in dry hot valley of the Jinsha River was investigated with analogous sites method. The results are as follows: 1) Deep soil organic carbon (SOC) storage significantly increased with stand age ( = 0.025), possibly due to fine root exudates and dissolved organic carbon transportation into deep soil and retention. 2) Total biomass carbon storage in the 30-year-old mixed plantation was 77.78 t C ha, 54 times reference wasteland and 9 times reference natural recovery shrub-grassland. However, total biomass carbon storage of 30-year-old mixed plantation was insignificantly lower than that of reference natural forest ( = 0.429). After 30 years of reforestation, plantation biomass carbon storage recovered to reference level, and its sequestration rate was 2.54 t C ha yr. 3) The total ecosystem carbon storage of 30-year-old mixed plantation was 185.50 t C ha, 2.38 times reference wasteland, 2.29 times reference natural recovery shrub grassland, and 29% lower than reference natural forest. It indicated that niche complementary, good stand structure, and characteristics of dominant species in mixed plantations facilitate more rapid carbon sequestration, especially biomass carbon in the dry hot valley.
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http://dx.doi.org/10.3390/ijerph16111937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6604323PMC
May 2019

Microbial Community Structure in the Sediments and Its Relation to Environmental Factors in Eutrophicated Sancha Lake.

Int J Environ Res Public Health 2019 05 31;16(11). Epub 2019 May 31.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.

To study the microbial community structure in sediments and its relation to eutrophication environment factors, the sediments and the overlying water of Sancha Lake were collected in the four seasons. MiSeq high-throughput sequencing was conducted for the V3-V4 hypervariable regions of the 16S rRNA gene and was used to analyze the microbial community structure in sediments. Pearson correlation and redundancy analysis (RDA) were conducted to determine the relation between microbial populations and eutrophic factors. The results demonstrated four main patterns: (1) in the 36 samples that were collected, the classification annotation suggested 64 phyla, 259 classes, 476 orders, 759 families, and 9325 OTUs; (2) The diversity indices were ordered according to their values as with summer > winter > autumn > spring; (3) The microbial populations in the four seasons belonged to two distinct characteristic groups; (4) pH, dissolved oxygen (DO), total phosphorus (TP), and total nitrogen (TN) had significant effects on the community composition and structure, which further affected the dissolved total phosphorus (DTP) significantly. The present study demonstrates that the microbial communities in Sancha Lake sediments are highly diverse, their compositions and distributions are significantly different between spring and non-spring, and Actinobacteria and Cyanobacteria may be the key populations or indicator organisms for eutrophication.
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http://dx.doi.org/10.3390/ijerph16111931DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6603867PMC
May 2019

A novel spatiotemporally anaerobic/semi-aerobic bioreactor for domestic solid waste treatment in rural areas.

Waste Manag 2019 Mar 29;86:97-105. Epub 2019 Jan 29.

School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.

To meet the requirements of domestic solid waste treatment and technological upgrading of bioreactors, a spatiotemporally anaerobic/semi-aerobic bioreactor (STASAB) was designed. The STASAB took full advantages of anaerobic and semi-aerobic bioreactors by the sequential alternation of anaerobic and semi-aerobic operation and by recirculation of mixed leachate from different-stage bioreactors. Results indicated that after the start-up stage, the pH of leachate in the STASAB always remained higher than 6.88, even in the hydrolysis and acidogenesis stage. The maximum total nitrogen concentration in the STASAB was 1461 mg·L, which was merely half that of the sequentially anaerobic/semi-aerobic bioreactor (SASAB) and had no adverse effects on the anaerobic process. Nitrogen removal in the STASAB reached 92.3%-95.5% when operated in the semi-aerobic phase and even reached 49.4% when operated in the anaerobic phase. The peak concentration of chemical oxygen demand was much lower and the anaerobic digestion lag time was much shorter in the STASAB than in the SASAB. The period of rapid biogas production in the STASAB was double that of the SASAB, which resulted in a 70% increase in biogas generation. Moreover, leachate could be exhausted by evaporation in just 3-5 months during the semi-aerobic phase. Therefore, the STASAB can eliminate acidogenic and ammonia inhibition during solid waste treatment, enhance the rate and extent of organic waste decomposition, rapidly initiate methanogenesis, enhance methane generation, and achieve zero leachate discharge (excluding rainfall infiltration). The STASAB is an efficient and feasible technique for treating domestic solid waste in rural areas.
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http://dx.doi.org/10.1016/j.wasman.2019.01.034DOI Listing
March 2019

Gene Diversity of Quinoprotein Glucose Dehydrogenase in the Sediment of Sancha Lake and Its Response to the Environment.

Int J Environ Res Public Health 2018 12 20;16(1). Epub 2018 Dec 20.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.

Quinoprotein glucose dehydrogenase (GDH) is the most important enzyme of inorganic phosphorus-dissolving metabolism, catalyzing the oxidation of glucose to gluconic acid. The insoluble phosphate in the sediment is converted into soluble phosphate, facilitating mass reproduction of algae. Therefore, studying the diversity of genes which encode GDH is beneficial to reveal the microbial group that has a significant influence on the eutrophication of water. Taking the eutrophic Sancha Lake sediments as the research object, we acquired samples from six sites in the spring and autumn. A total of 219,778 high-quality sequences were obtained by DNA extraction of microbial groups in sediments, PCR amplification of the gene, and high-throughput sequencing. Six phyla, nine classes, 15 orders, 29 families, 46 genera, and 610 operational taxonomic units (OTUs) were determined, suggesting the high genetic diversity of . genes came mainly from the genera of (1.63⁻77.99%), (0.13⁻56.95%), (0.32⁻25.49%), and (0.16⁻11.88%) in the phylum of Proteobacteria (25.10⁻98.85%). The abundance of these dominant -harboring bacteria was higher in the spring than in autumn, suggesting that they have an important effect on the eutrophication of the Sancha Lake. The alpha and beta diversity of genes presented spatial and temporal differences due to different sampling site types and sampling seasons. Pearson correlation analysis and canonical correlation analysis (CCA) showed that the diversity and abundance of genes were significantly correlated with environmental factors such as dissolved oxygen (DO), phosphorus hydrochloride (HCl⁻P), and dissolved total phosphorus (DTP). OTU composition was significantly correlated with DO, total organic carbon (TOC), and DTP. GDH encoded by genes transformed insoluble phosphate into dissolved phosphate, resulting in the eutrophication of Sancha Lake. The results suggest that genes encoding GDH may play an important role in lake eutrophication.
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http://dx.doi.org/10.3390/ijerph16010001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6339069PMC
December 2018

Graphene-Modulated Removal Performance of Nitrogen and Phosphorus Pollutants in a Sequencing Batch Reactor.

Materials (Basel) 2018 Nov 4;11(11). Epub 2018 Nov 4.

Haitian Water Grp. Co. Ltd., Chengdu 610059, China.

In this work, the influence of graphene on nitrogen and phosphorus in a batch reactor was studied. The impact of graphene on the removal performance of was investigated in a home-built sewage treatment system with seven identical sequencing batch reactors with graphene contents of 0 mg/L (T1), 0.05 mg/L (T2), 0.1 mg/L (T3), 0.2 mg/L (T4), 0.4 mg/L (T5), 0.8 mg/L (T6) and 10 mg/L (T7). The influence of graphene concentration and reaction time on the pollutant removal performance was studied. The malondialdehyde (MDA) and total superoxide dismutase (SOD) concentrations in each reactor were measured, and optical microscopy and scanning electron microscopy (SEM) characterizations were performed to determine the related mechanism. The results show that after 168 h, the total nitrogen (TN), ammonia nitrogen (AN) and total phosphorus (TP) removal rates of reactors T1⁻T7 become stable, and the TN, AN and TP removal rates were gradually reduced with increasing graphene concentration. At 96 h, the concentrations of both MDA and SOD in T1⁻T7 gradually increased as the graphene concentration increased. In optical microscopy and SEM measurements, it was found that graphene was adsorbed on the surface of , and entered cells, deforming and reducing . Through the blood plate count method, we estimated an average reduction of 16%. According to the water quality and microscopic experiments, it can be concluded that the addition of graphene causes oxidative damage to microalgae and destruction of the cell wall and cell membrane, inhibiting the nitrogen and phosphorus removal in reactors. This study provides theoretical and practical support for the safe use of graphene.
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http://dx.doi.org/10.3390/ma11112181DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266974PMC
November 2018

Treatment of Sewage Using a Constructed Soil Rapid Infiltration System Combined with Pre-Denitrification.

Int J Environ Res Public Health 2018 09 14;15(9). Epub 2018 Sep 14.

State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China.

The activated sludge process of the anaerobic/oxic (A/O) process has a good denitrification performance because it can make full use of the carbon source in the original sewage, and the denitrification can provide alkalinity for aerobic nitrification. The traditional constructed soil rapid infiltration (CSRI) system, on the other hand, has a poor nitrogen removal effect. Dividing the traditional CSRI system into two sections, one performs denitrification as an anoxic section, while the other performs nitrification as an aerobic section and is placed after the anoxic section. The nitrification liquid of the effluent from the aerobic section is mixed with the original wastewater and enters the anoxic section for denitrification. We expected that this would be improved by combining CSRI with a pre-denitrification step that would make full use of the carbon source in the original sewage. In a small-scale experimental model, the removal efficiencies of nitrogen, in the form of ammonium, nitrate, and total nitrogen (TN), as well as chemical oxygen demand (COD), were determined. The hydraulic load was varied, while the backflow reflux capacity was kept constant, to determine the effect on the pre-denitrification process. An average removal rate of 95.4% for NH₄⁺-N and 96% for COD could be obtained when a hydraulic load of 80 cm³(cm²·d) and a reflux ratio of 75% were applied. Under these conditions, the average removal rate of TN was 77.4%, which is much higher than what can be typically achieved with conventional CSRI systems.
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http://dx.doi.org/10.3390/ijerph15092005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6163630PMC
September 2018

Mitigation of methane emissions in a pilot-scale biocover system at the AV Miljø Landfill, Denmark: 1. System design and gas distribution.

Waste Manag 2017 May 21;63:213-225. Epub 2017 Jan 21.

Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark. Electronic address:

Greenhouse gas mitigation at landfills by methane oxidation in engineered biocover systems is believed to be a cost effective technology, but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation semi-passive biocover system was constructed at the AV Miljø Landfill, Denmark. The biocover system was fed by landfill gas pumped out of three leachate collection wells. An innovative gas distribution system was used to overcome the commonly observed surface emission hot spot areas resulting from an uneven gas distribution to the active methane oxidation layer, leading to areas with methane overloading. Performed screening of methane and carbon dioxide surface concentrations, as well as flux measurement using a flux chamber at the surface of the biocover, showed homogenous distributions indicating an even gas distribution. This was supported by results from a tracer gas test where the compound HFC-134a was added to the gas inlet over an adequately long time period to obtain tracer gas stationarity in the whole biocover system. Studies of the tracer gas movement within the biocover system showed a very even gas distribution in gas probes installed in the gas distribution layer. Also the flux of tracer gas out of the biocover surface, as measured by flux chamber technique, showed a spatially even distribution. Installed probes logging the temperature and moisture content of the methane oxidation layer at different depths showed elevated temperatures in the layer with temperature differences to the ambient temperature in the range of 25-50°C at the deepest measuring point due to the microbial processes occurring in the layer. The moisture measurements showed that infiltrating precipitation was efficiently drained away from the methane oxidation layer.
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http://dx.doi.org/10.1016/j.wasman.2017.01.013DOI Listing
May 2017

Evaluation and application of site-specific data to revise the first-order decay model for estimating landfill gas generation and emissions at Danish landfills.

J Air Waste Manag Assoc 2015 Jun;65(6):686-98

a Department of Environmental Engineering , Technical University of Denmark , Kongens Lyngby , Denmark.

Unlabelled: Methane (CH₄) generated from low-organic waste degradation at four Danish landfills was estimated by three first-order decay (FOD) landfill gas (LFG) generation models (LandGEM, IPCC, and Afvalzorg). Actual waste data from Danish landfills were applied to fit model (IPCC and Afvalzorg) required categories. In general, the single-phase model, LandGEM, significantly overestimated CH₄generation, because it applied too high default values for key parameters to handle low-organic waste scenarios. The key parameters were biochemical CH₄potential (BMP) and CH₄generation rate constant (k-value). In comparison to the IPCC model, the Afvalzorg model was more suitable for estimating CH₄generation at Danish landfills, because it defined more proper waste categories rather than traditional municipal solid waste (MSW) fractions. Moreover, the Afvalzorg model could better show the influence of not only the total disposed waste amount, but also various waste categories. By using laboratory-determined BMPs and k-values for shredder, sludge, mixed bulky waste, and street-cleaning waste, the Afvalzorg model was revised. The revised model estimated smaller cumulative CH₄generation results at the four Danish landfills (from the start of disposal until 2020 and until 2100). Through a CH₄mass balance approach, fugitive CH₄emissions from whole sites and a specific cell for shredder waste were aggregated based on the revised Afvalzorg model outcomes. Aggregated results were in good agreement with field measurements, indicating that the revised Afvalzorg model could provide practical and accurate estimation for Danish LFG emissions. This study is valuable for both researchers and engineers aiming to predict, control, and mitigate fugitive CH₄emissions from landfills receiving low-organic waste.

Implications: Landfill operators use the first-order decay (FOD) models to estimate methane (CH₄) generation. A single-phase model (LandGEM) and a traditional model (IPCC) could result in overestimation when handling a low-organic waste scenario. Site-specific data were important and capable of calibrating key parameter values in FOD models. The comparison study of the revised Afvalzorg model outcomes and field measurements at four Danish landfills provided a guideline for revising the Pollutants Release and Transfer Registers (PRTR) model, as well as indicating noteworthy waste fractions that could emit CH₄at modern landfills.
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http://dx.doi.org/10.1080/10962247.2015.1008653DOI Listing
June 2015

Evaluating the methane generation rate constant (k value) of low-organic waste at Danish landfills.

Waste Manag 2015 Jan 27;35:170-6. Epub 2014 Oct 27.

Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.

The methane (CH4) generation rate constant (k value, yr(-1)) is an essential parameter when using first-order decay (FOD) landfill gas (LFG) generation models to estimate CH4 generation from landfills. Four categories of waste (street cleansing, mixed bulky, shredder, and sludge waste) with a low-organic content, as well as temporarily stored combustible waste, were sampled from four Danish landfills. Anaerobic degradation experiments were set up in duplicate for all waste samples and incubated for 405 days, while the cumulative CH4 generation was continuously monitored. Applying FOD equations to the experimental results, half-life time values (t½, yr) and k values of various waste categories were determined. In general, similar waste categories obtained from different Danish landfills showed similar results. Sludge waste had the highest k values, which were in the range 0.156-0.189 yr(-1). The combustible and street cleansing waste showed k values of 0.023-0.027 yr(-1) and 0.073-0.083 yr(-1), respectively. The lowest k values were obtained for mixed bulky and shredder wastes ranging from 0.013 to 0.017 yr(-1). Most low-organic waste samples showed lower k values in comparison to the default numeric values in current FOD models (e.g., IPCC, LandGEM, and Afvalzorg). Compared with the k values reported in the literature, this research determined low-organic waste for the first time via reliable large-scale and long-term experiments. The degradation parameters provided in this study are valuable when using FOD LFG generation models to estimate CH4 generation from modern landfills that receive only low-organic waste.
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http://dx.doi.org/10.1016/j.wasman.2014.10.003DOI Listing
January 2015

Evaluating the biochemical methane potential (BMP) of low-organic waste at Danish landfills.

Waste Manag 2014 Nov 5;34(11):2251-9. Epub 2014 Aug 5.

Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.

The biochemical methane potential (BMP) is an essential parameter when using first order decay (FOD) landfill gas (LFG) generation models to estimate methane (CH4) generation from landfills. Different categories of waste (mixed, shredder and sludge waste) with a low-organic content and temporarily stored combustible waste were sampled from four Danish landfills. The waste was characterized in terms of physical characteristics (TS, VS, TC and TOC) and the BMP was analyzed in batch tests. The experiment was set up in triplicate, including blank and control tests. Waste samples were incubated at 55°C for more than 60 days, with continuous monitoring of the cumulative CH4 generation. Results showed that samples of mixed waste and shredder waste had similar BMP results, which was in the range of 5.4-9.1 kg CH4/ton waste (wet weight) on average. As a calculated consequence, their degradable organic carbon content (DOCC) was in the range of 0.44-0.70% of total weight (wet waste). Numeric values of both parameters were much lower than values of traditional municipal solid waste (MSW), as well as default numeric values in current FOD models. The sludge waste and temporarily stored combustible waste showed BMP values of 51.8-69.6 and 106.6-117.3 kg CH4/ton waste on average, respectively, and DOCC values of 3.84-5.12% and 7.96-8.74% of total weight. The same category of waste from different Danish landfills did not show significant variation. This research studied the BMP of Danish low-organic waste for the first time, which is important and valuable for using current FOD LFG generation models to estimate realistic CH4 emissions from modern landfills receiving low-organic waste.
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http://dx.doi.org/10.1016/j.wasman.2014.06.025DOI Listing
November 2014

Effect of biocover equipped with a novel passive air diffusion system on microbial methane oxidation and community of methanotrophs.

J Air Waste Manag Assoc 2012 Mar;62(3):278-86

School of Environment, Tsinghua University, Beijing, China.

A novel biocover with passive air diffusion system (PADS) was designed in this study. Its effect on landfill gas components in the macrocosms of simulated biocover systems was also investigated. The results show that O2 concentration increased in the whole profile of the macrocosms equipped with PADS. When simulated landfill gas (SLFG) flow rate was no more than 40 mL min(-1), the methane oxidation rate was 100%. The highest CH4 oxidation capacity reached to 31.34 mol m(-3) day(-1). Molecular microbiology analysis of the soil samples taken from the above macrocosm showed that the growth of type I methanotrophs was enhanced, attributable to enhanced air diffusion and distribution, whereas the microbial diversity and population density of type II methanotrophs were not so affected, as evidenced by the absence of any difference between the biocover equipped with PADS and that of the control. According to a phylogenic analysis, Methylobacter Methylosarcinafor type I, and Methylocystis, Methylosinus for type II, were the most prevalent species in the macrocosm with PADS.
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http://dx.doi.org/10.1080/10473289.2011.647236DOI Listing
March 2012