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environmental impact of radionuclide migration in groundwater from a low intermediate level radioactive waste repository

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Journal of environmental Sciences 2001年第2期13卷 180-184页

作者： J S Wang Z F Yang S S Li Z M Wang Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository environmental impact of radionuclide migration in groundwater from a low

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Estimation of the radionuclide distribution in sediment in coast area

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Journal of environmental Sciences 2001年第4期13卷 398-400页

作者： SHEN Zhen-yao YANG Zhi-feng LI Wei-juan NI Shi-wei YAO Lang-gen CAI Yuan Institute of Environmental Science Beijing Normal UniversityState Key Joint Laboratory of Environmental Simulation and Pollution ControlBeijing 100875China China Institute for Radiation Protection Key Laboratory of Nuclear Radiation Environmental SimulationTaiyuan 030006China

The study of the radionuelide distribution in sediment is a very important aspect in environmental impact of the low level radioactive liquid waste (LLW) from coastal nuclear facilities or nuclear power plant. Even now we do not know much about it. In this paper, a simple and useful method is put forward and it is used to estimate the nuclide distribution in sediment. The result showed that the LLW from nuclear facility or nuclear power plant will do a little harm to the sediment nearby. But the harm is not very serious. Much works have to be done before full understanding of the situation.

关键词： radionuclide coast area deposit characteristic sediment

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Organic peroxide production in the CI_2-ethane-air photoreaction system

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Science China Chemistry 2001年第1期44卷 74-79页

作者：齐斌胡敏陈忠明邵可声张远航唐孝炎 1. Department of Chemistry Shaanxi Normal University 710062 Xi’an China 2. State Key Laboratory of Environmental Simulation and Pollution Control Center of Environmental Sciences Peking University 100871 Beijing China

HPLC along with FT-IR technique was used to study the formation of organic peroxides in the Cl2-ethane-air photoreaction system. Ethyl hydroperoxide (CH3CH21OOH, EHP) and peroxyacetic acid ( CH3C(O)OOH, PAA) were conformed to be the peroxide product in the reaction system. In addition, methyl hydroperoxide (CH3OOH, hydroxymethyl hydroperoxide (HOCH2OOH, HMHP) and two unidentified organic peroxides were detected for the first time. EHP and were the dominant peroxide products. The identification of HMHP showed that Criegee biradical CH2OO may be formed as an intermediate in the oxidation of ethane. simulation results showed that photooxidation of ethane may make substantial contribution to source of organic peroxides in the atmosphere.

关键词： ethane HPLC FT-IR photooxidation organic peroxides

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A HIGH-ORDER-ACCURATE DIFFERENCE SCHEME WITH UNCONDITIONAL STABILITY FOR THE DIFFUSION EQUATION ON NONUNIFORM GRIDS

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Journal of Hydrodynamics 2001年第1期13卷 92-98页

作者： Wang Xuan, Yang Zhi-feng state key laboratory of Environment simulation and pollution control, Institute of environmental Sciences, Beijing Normal University, Beijing 100875, China[WT5”HZ] State Key Laboratory of Environment Simulation and Pollution Control Institute of Environmental Sciences Beijing Normal University

WT5”BZ]A high-order-accurate difference scheme with unconditional stability is developed for the diffusion equation on nonuniform grids. The theoretical analysis shows that the accuracy of this scheme is between third order and fourth order, and fourth-order accuracy is achieved in the case of the same grid steps being used within the computational domain. Two numerical examples are given to demonst ate the advantages of the proposed scheme. Compared with the conventional difference scheme, more accurate numerical solution can be obtained by using the proposed scheme even with relatively larger grid sizes. It is also pointed out that the appropriate structure of the nonuniform grid can not only make the proposed scheme more practical, but lead to a solution superior to that for a uniform grid structure. [WT5”HZ]

关键词： ]finite difference scheme diffusion equation nonuniform grid high accuracy computational fluid dynamics

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SPECTRUM CHARACTERISTICS OF MAJOR IONCONCENTRATIONS AT WUHAN SECTOIN OF THECHANGJIANG RIVER

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Chinese Geographical Science 2001年第4期11卷 29-34页

作者： XIA Xing-hui1, CHEN Jing-sheng2, CAI Xu-yi3(1. Institute of environmental Sciences, Beijing Normal University / state key Joint laboratory of environmentalsimulation and pollution control, Beijing 100875, P. R. China 2. Department of U Institute of Environmental Sciences Beijing Normal University/ State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing P.R. China Department of Urban & Environmental Science Peking University Beijing P. R. China Geography Department Graduate School of University of Science and Technique of China Beijing P. R. China

ABSTRACT: Spectrum analyses of water quality time series have been carried out for five hydrometric stations including Wuhan hydrometric station of the Changjiang( Yangtze) River, etc. The fluctuations of Ca2 +, Mg2+ and HCO3-concentrations in river water under different physical geography conditions have about two-year cycle which is corresponding to hydrometeorological quasi-biannual-oscillation(QBO). Na + Cl- SO2-4 have about two-year cycle in the area lightly affected by human activities while two-year cycle doesn’t exist in the area heavily affected by human activities. All the fluctuations of major ions have about three-month cycle. The river discharge fluctuation accounts for 43. 9% , 45.1%, 54.3%, 33.9%, 30.3% and 42. 7% of the variance of Ca2 +, Mg2+ HC03-, Na+ Cl-, SO2-4, respectively, at Wuhan from 1962 to 1985. According to the spectrum characteristic of major ions, the duration of the time series has to be at least 13 years for trend analysis of monthly water quality data.

关键词： major ions spectrum characteristic of water quality water quality change the Changjiang River

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Bioaugmentation: a new strategy for removal of recalcitrant compounds in wastewater—a case study of quinoline

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Journal of environmental Sciences 2000年第1期12卷 24-27页

作者： HAN Li-ping WANG Jian-long SHI Han-chang QIAN Yi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

To demonstrate the feasibility of using bioaugmentation to enhance biodegradation of quinoline, four strains capable of using quinoline as sole source of carbon, nitrogen and energy were isolated from different environmental samples by enrichment technique. Screening for quinoline degrader with the highest quinoline mineralizing rate was carried out in respirometer and one bacterium identified as \%Burkholderia pickettii W2\% was chosen as inoculum in bioaugmentation tests. Quinoline biodegradation experiment results showed that this bacterium degraded quinoline very quickly. 100, 200 and 500 mg/L quinoline can be transformed completely within 1, 2 and 7 hours respectively. A bioaugmentation procedure was proposed and laboratory experiments confirmed that bioaugmentation was an effective way to improve the performance of traditional wastewater treatment facilities for quinoline removal. The effect of inoculum size on bioaugmentation was also investigated in this paper.

关键词： bioaugmentation biodegradation quinoline inocula CLC number: X703 Document code: A

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Ceramic Ultra Filtration Membrane Bioreactor for Domestic Wastewater Treatment

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Tsinghua Science and Technology 2000年第3期5卷 283-287页

作者：文湘华邢传宏钱易 State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Engineering Tsinghua University Bcljing 100084 China

A long term domestic wastewater treatment experiment was conducted using a recirculating ceramic ultra filtration membrane bioreactor (CUFMB) system. Three experiments were run with a hydraulic retention time of 5h, sludge retention times of 5d, 15d, and 30d and a membrane surface flow rate of 4m/s. The experiment studied the membrane fouling mechanism and cleaning techniques. The results show that a CUFMB system can provide continuous good quality effluent which is completely acceptable for reuse. The system is also not affected by fluctuations of the inlet flow. The CUFMB sludge loading rate is similar to that of conventional biological treatment units. However, the volumetric loading rate of the CUFMB is 24 times that of conventional biological treatment units. Membrane fouling occurs due to channel clogging, which could be easily removed, and surface fouling, which can be effectively removed using the method described in this work which includes water rinsing, base cleaning, and acid washing. 

关键词： ceramic membrane bioreactor ultra filtration hydraulics membrane fouling cleaning

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Performance of Submerged Membrane Bioreactor for Domestic Wastewater Treatment

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Tsinghua Science and Technology 2000年第3期5卷 237-240页

作者：黄霞桂萍钱易 State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

In the present research, a submerged membrane bioreactor was tested to treat domestic wastewater. Three experimental runs were conducted all with a hydraulic retention time of 5h and sludge retention times (SRTs) of 5, 10, and 20 d. The pollutant removal performance of the membrane bioreactor, the membrane effluent quality, and a kinetic model for sludge growth in the bioreactor were investigated. The combined process was capable of removing over 90% of both COD (chemical oxygen demand) and NH 3 N on the average. The total removal for COD was almost independent of SRT, but that for NH 3 N improved with increasing SRT. Membrane effluent quality meets the water quality standard for reuse issued by the Ministry of Construction of China. Increasing SRT causes the concentrations of suspended solids (SS) and volatile suspended solids (VSS) in the bioreactor to increase. However, the ratio of VSS/SS did not change much. Kinetic analysis showed that the sludge yield coefficient (kg VSS·kg COD -1 ) and the endogenous coefficient of microorganisms were 0.25 and 0.04d -1 , which are similar to those of the conventional activated sludge process. 

关键词： submerged membrane bioreactor domestic wastewater treatment pollutant removal performance effluent quality sludge retention time sludge growing kinetics

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Distribution, removal and chemical forms of heavy metals in polluted rice seed

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Toxicological and environmental Chemistry 2000年第3-4期76卷 137-145页

作者： He, Mengchang Yang, Jurong Cha, Yan State Key Joint Laboratory of Environmental Simulation and Pollution Control Institute of Environmental Sciences Beijing Normal University Beijing 100875 China State Key Joint Laboratory of Environmental Simulation and Pollution Control Institute of Environmental Sciences Beijing Normal University Beijing 100875 China

In this paper, the distribution, removal and binding forms of heavy metals in polluted seeds of rice were studied using the methods of histochemistry and biochemistry. The results indicate that the distribution of heavy metals in rice grains was very uneven. The heavy metals in rice grains chiefly exist in association with the parts of high protein. Separation of proteins by Sephadex chromatography and subsequent analysis by atomic absorption spectroscopy revealed that Cd, Pb and As were mainly bound to protein of 54.5 and 5.50 kD molecular weights. During the rice processing, the concentrations of heavy metals in the edible rice decrease greatly, for some heavy metals in these parts of chaff, coarse rice bran and fine rice bran were removed.

关键词： Binding forms Distribution Food processing Gel chromatography Heavy metals Rice grains

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Bioadsorption of 4-Chlorophenol to the Activated Sludge

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Tsinghua Science and Technology 2000年第3期5卷 241-245页

作者：王建龙 Nigel Horan Ed.Stentiford 钱易 State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China School of Civil Engineering Leeds University LS 9JT UK

The adsorption behaviour of 4 chlorophenol from aqueous solution to activated sludge was quantitatively characterized in this paper. The effects of the initial pH values, initial chlorophenol concentration and adsorbent dosage on bioadsorption were investigated. The maximum adsorption capacity was found to be 110.5 mg/g at 100 mg/L initial concentration. The Freundlich and Langmuir adsorption isotherms were applied to describe the biosorption processes and the isotherm constants were evaluated. 

关键词： 4-chlorophenol priority pollutant bioadsorption activated sludge

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