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Sludge reduction with Tubificidae and the impact on the performance of the wastewater treatment process

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Journal of environmental Sciences 2007年第3期19卷 257-263页

作者： GUO Xue-song LIU Jun-xin WEI Yuan-song LI Lin research center for eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

To reduce excess sludge, a Tubificidae reactor was combined with an integrated oxidation ditch with vertical circle （IODVC）, and a new integrated system was developed for wastewater treatment, A pilot-scale of this integrated system was tested to investigate the sludge reduction with Tubificidae and the impact on effluent quality and sludge production. The dominant worm was Branchnria Sowerbyi in the Tubificidae reactor after inoculation of Branchnria Sowerbyi and Limnodrilns sp., and the maximal volume density of wet Tubificidae in vessels of the Tubificidae reactor was 17600 g/m^3. Two operational modes, treating the excess sludge （first mode） and the returned sludge （second mode） of IODVC by the Tubificidae reactor, were used in this experiment. The results showed that the excess sludge reduction rate was 46.4% in the first mode, and the average sludge yield of the integrated system was 6.19× 10^-5 kg SS/kg COD in the second mode. Though the sludge returned to IODVC via the Tubificidae reactor, it had little impact on the effluent quality and the sludge characteristics of the IODVC. No new type of recalcitrant substance in the supernatant was discharged into the environment when the sludge was treated by Tubificidae. The experimental results also indicated that no significant changes occurred on the viscosity, specific resistance, and the floc size distribution of the sludge.

关键词： integrated wastewater treatment system sludge reduction wastewater treatment Tubificidae

Variation of airborne quartz in air of Beijing during the Asia-Pacific economic Cooperation economic Leaders' Meeting

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Journal of environmental Sciences 2016年第1期28卷 62-68页

作者： Gang Li Yingming Li Hongxing Zhang Honghua Li Guanjun Gao Qian Zhou Yuan Gao Wenjuan Li Huizhong Sun Xiaoke Wang Qinghua Zhang State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing Urban ecosystem research Station Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Environment and Health Jianghan University

Quartz particles are a toxic component of airborne paniculate matter（PM）.Quartz concentrations were analyzed by X-ray diffraction in eighty-seven airborne PM samples collected from three locations in Beijing before,during,and after the Asia-Pacific economic Cooperation（APEC） Leaders＇ Meeting in *** results showed that the mean concentrations of quartz in PM samples from the two urban sites were considerably higher than those from the rural *** quartz concentrations in samples collected after the APEC meeting,when the pollution restriction lever was lifted,were higher than those in the samples collected before or during the APEC *** quartz concentrations ranged from 0.97 to 13.2 μg/m^3,which were among the highest values amid those reported from other *** highest quartz concentration exceeded the Californian Office of environmental Health Hazard Assessment reference exposure level and was close to the occupational threshold limit values for occupational ***,a correlation analysis showed that quartz concentrations were positively correlated with concentrations of pollution parameters PM10,PM2.5,SO2 and NOx,but were negatively correlated with O3 *** results suggest that the airborne quartz particles may potentially pose health risks to the general population of Beijing.

关键词： Air pollution Carcinogen Haze PM10 Quartz

A case study of Asian dust storm particles:Chemical composition,reactivity to SO_2 and hygroscopic properties

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Journal of environmental Sciences 2012年第1期24卷 62-71页

作者： Qingxin Ma Yongchun Liu Chang Liu Jinzhu Ma Hong He research center for eco-environmental Sciences Chinese Academy of SciencesBeijing 100085China

Mineral dust comprises a great fraction of the global aerosol loading,but remains the largest uncertainty in predictions of the future climate due to its complexity in composition and physico-chemical *** this work,a case study characterizing Asian dust storm particles was conducted by multiple analysis methods,including SEM-EDS,XPS,FT-IR,BET,TPD/mass and Knudsen cell/*** morphology,elemental fraction,source distribution,true uptake coefficient for SO 2,and hygroscopic behavior were *** major components of Asian dust storm particles are aluminosilicate,SiO 2 and CaCO 3,with organic compounds and inorganic nitrate coated on the *** has a low reactivity towards SO 2 with a true uptake coefficient,5.767×10-6,which limits the conversion of SO 2 to sulfate during dust storm *** low reactivity also means that the heterogeneous reactions of SO 2 in both dry and humid air conditions have little effect on the hygroscopic behavior of the dust particles.

关键词： DRIFTS mineral dust SO2 reaction water adsorption

Effects of elevated ozone on growth and yield of field-grown rice in Yangtze River Delta,China

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Journal of environmental Sciences 2008年第3期20卷 320-325页

作者： CHEN Zhan WANG Xiaoke FENG Zhaozhong ZHENG Feixiang DUAN Xiaonan YANG Wenrui research center for eco-environmental Sciences Chinese Academy of Scienees Beijing 100085 China

With rapid industrialization and urbanization in the Yangtze Delta, China, the tropospheric ozone concentration has increased to levels that induce crop yield loss. Rice, a widely grown crop in China, was investigated in field-established, open-top chambers. Four treatments were used： charcoal-filtered air （CF）, non-charcoal-filtered air （NF）, and charcoal-filtered air with two levels of additional ozone （O3-1 and O3-2）. The AOT40s （accumulated hourly mean ozone concentration above 40 ppbv） were 0, 0.91, 23.24, and 39.28 ppmv.h for treatment of CE NF, O3-1, and O3-2, respectively. The rice height and biomass were reduced in the elevated ozone concentration. Less organic matter partitioning to roots under the elevated ozone significantly decreased rice root activity. The yield loss was 14.3% and 20.2% under O3-1 and O3-2 exposure, respectively. This was largely caused by a reduction in grain weight per panicle.

关键词： ozone rice growth yield Yangtze Delta

A fishy odor episode in a north China reservoir: Occurrence, origin, and possible odor causing compounds

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Journal of environmental Sciences 2013年第12期25卷 2361-2366页

作者： Yunyun Zhao Jianwei Yu Ming Su Wei An Min Yang State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences

A significant outbreak of fishy odor occurred in a reservoir located in Inner Mongolia, China, in the winter of 2011, and the odor rating, algal density and concentrations of some potential odorous compounds were monitored over a period of two months. The peak odor rating of the fishy odor was 7 according to flavor profile analysis. Among the dominant algal species （two diatom and one chrysophyte species） observed during the survey, the chrysophyte Dinobryon sp. was the most abundant species, with the peak density recorded at 88,520 cells/mL. Seven potential algal metabolites including heptanal, 2,4-heptadienal, 2,4-decadienal, nonanal, 2-octenal, 2,6- nonadienal and hexanal were detected. The principal component analysis result showed that n-hexanal, n-heptanal and 2,4-decadienal, possibly the metabolites of diatoms, and 2,4-heptadienal, possibly the metabolite of Dinobryon sp., might have contributed to the fishy odor episode. This study demonstrated that the fishy odor episode in this reservoir might be caused by the abnormal growth of chrysophytes and diatoms under the ice-cover.

关键词： fishy odor chrysophyte diatom reservoir drinking water flavor profile analysis

Treatment of black liquor from the papermaking industry by acidification and reuse

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Journal of environmental Sciences 2003年第5期15卷 697-700页

作者： YANG Wen bo, MU Huan zhen, HUANG Yan chu (research center for eco environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. research center for eco-environmental Sciences Chinese Academy of Sciences 北京 100085

Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry. By the treatment, the solid materials in black liquor are transferred into two by products and the other components are reused or evaporated. Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved.

关键词： black liquor acidification reuse lignin water reducing agent

Simultaneous determination of brominated phenols in soils

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Journal of environmental Sciences 2013年第11期25卷 2306-2312页

作者： Wei Han Sen Wang Honglin Huang Lei Luo Shuzhen Zhang State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A （TBBPA）, tribromophenol （TBP）, dibromophenols （DBPs） and monobromophenols （MBPs） in soils using gas chromatography-mass spectrometry analysis （GC/MS） was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor （lower than 55%） due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils.

关键词： brominated phenols analysis soil derivatization GC/MS

Mercury in leaf litter in typical suburban and urban broadleaf forests in China

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Journal of environmental Sciences 2011年第12期23卷 2042-2048页

作者： Zhenchuan Niu Xiaoshan Zhang Zhangwei Wang Zhijia Ci research center for eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

To study the role of leaf litter in the mercury （Hg） cycle in suburban broadleaf forests and the distribution of Hg in urban forests, we collected leaf litter and soil from suburban evergreen and deciduous broadleaf forests and from urban forests in Beijing. The Hg concentrations in leaf litter from the suburban forests varied from 8.3 to 205.0 ng/g, with an average （avg） of （49.7 ± 36.9） ng/g. The average Hg concentration in evergreen broadleaf forest leaf litter （50.8 ± 39.4） ng/g was higher than that in deciduous broadleaf forest leaf litter （25.8 ± 10.1） ng/g. The estimated Hg fluxes of leaf litter in suburban evergreen and deciduous broadleaf forests were 179.0 and 83.7 mg/（ha·yr）, respectively. The Hg concentration in organic horizons （O horizons）（（263.1 ± 237.2） ng/g） was higher than that in eluvial horizons （A horizons）（（83.9 ± 52.0） ng/g）. These results indicated that leaf litterfall plays an important role in transporting atmospheric mercury to soil in suburban forests. For urban forests in Beijing, the Hg concentrations in leaf litter ranged from 8.8–119.0 （avg 28.1 ± 16.6） ng/g, with higher concentrations at urban sites than at suburban sites for each tree. The Hg concentrations in surface soil in Beijing were 32.0–25300.0 ng/g and increased from suburban sites to urban sites, with the highest value from Jingshan （JS） Park at the centre of Beijing. Therefore, the distribution of Hg in Beijing urban forests appeared to be strongly influenced by anthropogenic activities.

关键词： mercury broadleaf forests leaf litter soil flux

In situ adsorption-catalysis system for the removal of o-xylene over an activated carbon supported Pd catalyst

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Journal of environmental Sciences 2009年第7期21卷 985-990页

作者： HUANG Shaoyong, ZHANG Changbin, HE Hong research center for eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. research center for eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

An activated carbon （AC） supported Pd catalyst was used to develop a highly efficient in situ adsorption-catalysis system for the removal of low concentrations of o-xylene. In this study, three kinds of Pd/AC catalysts were prepared and tested to investigate the synergistic efficiency between adsorption and catalysis for o-xylene removal. The Pd/AC catalyst was first used as an adsorbent to concentrate dilute o-xylene at low temperature. After saturated adsorption, the adsorbed o-xylene was oxidized to CO2 and H20 by raising the temperature of the catalyst bed. The results showed that more than 99% of the adsorbed o-xylene was completely oxidized to CO2 over a 5% Pd/AC catalyst at 140℃. Brunauer-Emmett-Teller （BET） analysis, scanning electron microscopy （SEM）, temperatureprogrammed desorption （TPD）, and temperature-programmed oxidation （TPO） were applied to investigate the physical properties of o-xylene adsorption-desorption and the in situ adsorption-catalysis activity of the AC support and Pd/AC catalyst. A synergistic relationship between the AC support and the active Pd species for the removal of low concentrations of o-xylene was established.

关键词： in situ adsorption-catalysis Pd/AC volatile organic compounds