小型污染气源的封闭治理——防汞箱的研制

本文提出将产生少量污染气体的操作在透明玻罩的隔离下进行,将罩内气体抽出净化至工作场所卫生标准后在室内排放,以免影响环境。以研制防汞箱为例,说明这种设想是可能实现的。

大豆压榨厂污染气源处理和监测

采取有效措施限制或减少油厂排放的的污染气源和污染量,在锅炉和其他排废气源安装除尘设备。在5000t/d大豆压榨厂调试期,经广东省环保检测站9个月跟踪监测,环保排放指标达到或超过省或国家环保指标。

啤酒厂气源微生物污染和防治

气源是啤酒厂微生物污染的来源之一。酿造前期用气 (主要指冷麦汁充氧 )的卫生指标已经引起了酿造者足够的注意 ,由于啤酒很快就进行巴氏灭菌 ,因而对酿造后期用气 (包括滤酒工序和灌装工序 )的质量重视程度不够。列举了气源中的一些常见微生物 ,以及它们对啤酒的危害 ,简单介绍了气源的取样方法 。

大豆压榨厂废气污染治理

采取有效措施限制或减少油厂排放的污染气源和污染量,对锅炉和其他排废气源进行处理。在5000 t/d大豆压榨厂调试期间,经环保检测部门跟踪检测,环保排放指标达到或超过有关标准。

Distribution, Chemical Speciation, and Environmental Risk Assessment of Heavy Metals in Tailings Soils near Dexing Copper Mine, China

To complement information of heavy metals＇ distribution, chemical speciation, activity and environmental risks in agricultural soils surrounding tailings, a total of 16 samples obtained from the 4 # railings site of Dexing copper mine of China were investigated. The total concentrations of heavy metals Zn, Fe, Cu, Pb, Cd, Cr, Hg, As, Mn, Ag, Co, and Ni were determined by inductively coupled plasma-atomic emission spectrometry. Chemical speciations of Cu, Cd, and Zn were investigated with the procedures recommended by Tessier（1979）. Two different assessment approaches （GB 15618- 1995 and risk assessment code, RAC ） were employed to estimate heavy metals＇ environmental risks. Results indicated that heavy metals, especially Cu and Cd were in high levels of accumulation in these samples. Chemical speciation analysis results revealed that Cu was mainly in organic matter bound fraction （ORG） and residual fraction （ RES）, and Cd was predominantly in exchangeable fraction （EXC）, while Zn appeared mainly with the RES fraction. Environmental risk analysis results showed that Cd was in ＂heavy＂ pollution level （ classification m ） in almost all samples, which may exert ＂high＂ or ＂very high＂ environmental risks. Whereas, for Cu, one fourth samples showed ＂heavy＂ pollution level, but were located in ＂low＂ or ＂medium＂ environmental risk ranks. For Zn, many samples were grouped in ＂light＂ pollution level （ classification II ）, but were related to ＂ medium＂ and ＂ high＂ environmental risk ranks. These results indicated heavy pollution and high environmental risk of Cd in soils surrounding the 4# tailings site, which should be paid more attention to. Meanwhile, for Cu and Zn, the contrary results obtained by different environmental risk assessment approaches, may suggest that a more scientific, adequate environmental risk assessment criterion should consider both total content and chemical speciation activity of heavy metals.

Microbial Function, Enzymatic Activities and Diversity in an Anaerobic-Anoxic-Aerobic Reactor System

Enzymatic activities of beta-gincosidase （ β-GLC ）, （ LAP）, and alkaline phosphatase （ APA）, corresponding to nutrient eliminations, and the microbial community structures were analyzed in an anaerobic-anoxic-aerobic reactor system. Results showed that most activity of β-GLC （64.2 μmoi/（ L · h ）） associated with the largest fraction of small- molecular-weight carbohydrates was found in the aerobic reactor, indicating the existence of coupled hydrolysis-uptake mechanism in the aerobic bacteria. Similar activities of LAP presented in the anoxic and aerobic environments, whose increases accompanied by increments in nitrogen uptake rates greatly accelerated the processes of aerobic nitrification and anoxic denitrification. The highest APA activity displayed in the anaerobic reactor, however, dephosphorization performance was mainly achieved under aerobic condition. Microbial community fingerprints generated by polymerase chain reaction amplification and denaturing gradient gel dectrophoresls （ PCR-DGGE ） revealed that Proteobacterium, Actinobacterium, and Nitrosplra were the predominant classes in the activated sindge and there was no evidence of community variations among each function reactor in the system with biomass recycling.

Quantifying Changes of Mobile Source Air Pollution in Metropolitan Areas Using Vehicle Emission Model MOVES

Vehicle emissions are one of the major sources of urban air pollution and are also called mobile source emissions. A large amount of gross vehicle emissions is generated by vehicles commuting between residential homes and the workplace. Homebuyers generally prefer to purchase residential houses that are relatively less expensive, albeit at the cost of relatively longer commuting times. Consumers usually consider additional travel time, fuel consumption, and other personally concerned factors, with less apprehension about the extra air pollution possibly generated. In cities with populations between 15,000 and 1,000,000, an increase of one additional minute of average commuting time is associated with a reduction of 1.9 dollars in housing price per square foot （p-value： 0.038）. To account for the generation of additional air pollution, this paper numerically characterizes factors related to air pollutants caused by additional travel time due to housing prices. Air pollutants such as CO, CO2, NO2, NO, NOx and SO2 as well as fuel consumption were estimated by MOVES （motor vehicle emissions simulator）. The results will be a useful reference to generate recommendations for more efficient reduction of mobile source air pollution in metropolitan areas through joint efforts by government, agencies, the public, and industry from multiple fields including environment protection, land use, housing markets, transportation management, and law enforcement.

STUDY ON EVOLUTION REGULARITIES AND ABSORPTION CHARACTERISTICS OF SULFIDE DURING BITUMINOUS BRIQUETTE HORIZONTAL COMBUSTION

This paper discusses the evolution regularity and the absorption characters of sulfide for bituminous briquette burned in a horizontal burning fornace. The evolution rate of sulphur is affected by some factors, such as the sulphur content in the burning coal, burning time and the mean excess air coefficient in the furnace. With processing the experimental result, the calculation related expression has been obtained to predict the evolution rate of sulfide. The sulphur absorption efficiency of briquette is affected by tbe factors such as the character of the sulphur sorbent, the type of the coal and the operating parameters. By means of appropriately adjusting the calciumsulphur mole ratio, the mean excess air coefficient and the time-interval between pushing two layer briquettes, a high sulphur absorption efficiency (>74% ) can be obtained.

Preface

Owing to the fast economic growing and the concern over greenhouse gases and air pollution, the development of nuclear energy is one important option to meet the expanded energy consumption in our future. To achieve that goal, continuing and reliable supplies of uranium are critical to future nuclear power projects. As is well known, global terrestrial reserves of uranium are limited and the deposits in China are relatively small.

The effect of temperature changes and K supply on the reproduction and growth of Bolboschoenus planiculmis

Aims Climate warming and agricultural non-point source pollution both resulting from anthropogenic activities have been projected to affect plant reproduction and growth in wetlands worldwide.In order to predict and mitigate impacts of these anthropogenic activities,it is important to investigate how marsh plants respond to such environmental changes.Methods In this study,Bolboschoenus planiculmis,a tuberous sedge with a wide distribution range in Eurasia,was selected to examine the effect of air temperature changes(15,20 and 25°C over 24 h;20/10 and 30/15°C,day/night)and K supply(0,1,3,9 and 18 mmol/L)on its reproductive and growth traits in climate chambers.Important Findings We found that high constant temperatures(20 and 25°C)were more beneficial for tuberization of B.planiculmis than high alternating temperatures(30/15°C),whereas aboveground biomass and shoot height were generally largest at high temperatures(30/15 and 25°C).Both reproductive and growth traits of B.planiculmis showed hump-shaped relationships with K supply,with an optimum K concentration of around 1–3 mmol/L.The combination of high constant temperatures and optimal K concentrations promoted reproductive traits the most,whereas the combination of higher temperatures(30/15 and 25°C)and K concentrations up to 9 mmol/L increased growth traits only.We therefore conclude that population abundance of B.planiculmis might benefit from global warming and the additional K supply.