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1.
在大气环境污染研究中,不仅要测量污染物地面浓度,还必须在大气近地层测量污染物的时间和空间分布,以了解污染物的输送,扩散以及物理化学变化过程,验证和改进污染物输送、扩散的数学模式。因此传统的定点监测仪器已不能完全满足需要,各种遥测仪器便应运而生,激光雷达就是其中的  相似文献   

2.
一、前言随着电力工业的不断发展,排入大气环境的烟尘越来越多。我国环境工作者研究表明,目前我国大气中以尘的污染为主,烟尘是城市大气污染中的主要污染物之一,我国近期环保工作的重点是解决大气中尘的污染。解决这个问题,首先是应了解和研究各地大气中颗粒物(即气溶胶)的浓度和粒度分布规律。在新建、扩建电厂的环境予评价中,须粒物的影响预测也是评价中的主要内容之一。  相似文献   

3.
介绍了FLUENT软件的基本原理、方法及主要特点,综述了其在燃煤电厂大气污染控制、大气污染扩散、大气污染物生成模拟方面的研究进展和实际应用情况,在此基础上,总结了FLUENT软件在燃煤电厂大气污染领域应用中存在的问题,并提出了今后的研究方向和发展趋势。  相似文献   

4.
本文介绍了沿海大气过程和边界层结构特点及其对沿海电站空气污染物散布的影响,国内外的有关研究状况与测试技术,以及现有沿海大气污染物扩散模式,并对今后开展沿海空气污染气象研究工作提出了意见。  相似文献   

5.
前言等斜率灰色聚类法是以等斜率的方式来构成白化函数,从而较大地拓展了各类白化函数所表达的污染范围,并以修正系数对白化函数进行修正,使相邻白化函数在评价级别分界值上具有相同的函数值,避免了边界值附近的误判现象,提高了分辩率,解决了边界值问题。该法既能评价出各评价对象的污染级别,也能同时评价出污染的轻重顺序。本文用等斜率及色聚类法评价衡水电厂大气环境质量现状,其结果与实际是相符的。1评价方法1,王建立白化函数首先选择GB3O95-96(大气环境质量标准》作为分级标准,然后依据分级标准确定评价对象的污染级别,…  相似文献   

6.
湿法烟气脱硫中GGH对污染物扩散影响初探   总被引:24,自引:2,他引:24  
介绍了烟气换热器(GGH)在湿法烟气脱硫工程中的应用情况,从大气污染物扩散的角度,分析探讨了设置或取消GGH情况下烟气污染物对大气环境的影响。  相似文献   

7.
80年代初美国环保局为研究点源大气扩散特征所需的大气测量要求,组织一个专家工作组,提出数据采集和记录方法、专门的测量技术和精度以及测量规范化等方面意见。专家组的工作报告中强调用湍流强度的现场测试表征大气扩散特征甚于以Pasquill-  相似文献   

8.
应用空气质量模式预测大气污染物的浓度和分布,有其特定的适用条件和限制。评价模式的性能和分析预报结果的质量,对于改善空气污染控制和管理具有重要意义。文中介绍了模式性能评价的内容、方法、量度等方面有关问题。  相似文献   

9.
我国现行环境保护法规以控制排放浓度为基础,利用大气和水体的扩散稀释能力使环境中污染物浓度不超过规定限度,但污染物排放总量实际上并未减少。只有实行排放总量控制,才可从总体上有效地控制污染。限于我国的经济条件,不能象工业发达国家  相似文献   

10.
物元分析在大气环境质量评价中的应用   总被引:2,自引:0,他引:2  
冯玉国 《化工环保》1994,14(3):163-166
将大气环境质量级别、评价指标及其特征值作为物元,根据大气环境质量标准建立关联函数,提出了一种用物元分析评价大气环境质量的方法。用实例与贴近度法及模糊综合评判法进行了对比,结果完全一致。  相似文献   

11.
氯气泄漏扩散过程及后果评价的研究现状分析   总被引:1,自引:0,他引:1  
综述了氯气泄漏扩散过程及后果评价的研究成果。从现场试验、实验室模拟和数学模拟三方面分析了氯气泄漏扩散各研究方法的优势和局限性。强调了氯气泄漏扩散后果评价的必要性。指出:必须针对中国特有的一些重气扩散建立专属知识产权的数学模型;不同层次数学模型的精度皆有待于进一步提高;需加强基于特定数学模型的全过程统一界面模拟程序的开发。  相似文献   

12.
A field demonstration of an enhanced in-situ bioremediation technology was conducted between March 1998 and August 1999 at the ITT Industries Night Vision (ITTNV) Division plant in Roanoke, Virginia. The bioremediation process was evaluated for its effectiveness in treating both chlorinated and nonchlorinated volatile organic compounds (VOCs) in groundwater located in fractured bedrock. Chlorinated compounds, such as trichloroethene (TCE), in fractured bedrock pose a challenging remediation problem. Not only are chlorinated compounds resistant to normal biological degradation, but the fractured bedrock presents difficulties to traditional techniques used for recovery of contaminants and for delivery of amendments or reagents for in-situ remediation. The demonstration was conducted under the U.S. Environmental Protection Agency's Superfund Innovative Technology Evaluation (SITE) program. The SITE program was established to promote the development, demonstration, and use of innovative treatment technologies for the cleanup of Superfund and other hazardous waste sites. This article presents selected results of the demonstration and focuses on understanding the data in light of the fractured bedrock formation. © 2002 Wiley Periodicals, Inc.  相似文献   

13.
This paper presents an overview of municipal solid waste (MSW) management in Beijing City. Beijing, the capital of China, has a land area of approximately 1368.32 km2 with an urban population of about 13.33 million in 2006. Over the past three decades, MSW generation in Beijing City has increased tremendously from 1.04 million tons in 1978 to 4.134 million tons in 2006. The average generation rate of MSW in 2006 was 0.85 kg/capita/day. Food waste comprised 63.39%, followed by paper (11.07%), plastics (12.7%) and dust (5.78%). While all other wastes including tiles, textiles, glass, metals and wood accounted for less than 3%. Currently, 90% of MSW generated in Beijing is landfilled, 8% is incinerated and 2% is composted. Source separation collection, as a waste reduction method, has been carried out in a total of 2255 demonstration residential and commercial areas (covering about 4.7 million people) up to the end of 2007. Demonstration districts should be promoted over a wider range instead of demonstration communities. The capacity of transfer stations and treatment plants is an urgent problem as these sites are seriously overloaded. These problems should first be solved by constructing more sites and converting to new treatment technologies. Improvements in legislation, public education and the management of waste pickers are problematic issues which need to be addressed.  相似文献   

14.
This study characterises the heavy-metal content in leachates collected from eight landfills in France. In order to identify heavy metal occurrence in the different size fractions of leachates, a cascade filtration protocol was applied directly in the field, under a nitrogen gas atmosphere to avoid metal oxidation. The results of analyses performed on the leachates suggest that most of the metals are concentrated in the <30 kDa fraction, while lead, copper and cadmium show an association with larger particles. Initial speciation calculations, without considering metal association with organic matter, suggest that leachate concentrations in lead, copper, nickel and zinc are super-saturated with respect to sulphur phases. Speciation calculations that account for metal complexation with organic matter, considered as fulvic acids based on C1(s) NEXAFS spectroscopy, show that this mechanism is not sufficient to explain such deviation from equilibrium conditions. It is therefore hypothesized that the deviation results also from the influence of biological activity on the kinetics of mineral phase precipitation and dissolution, thus providing a dynamic system. The results of chemical analyses of sampled fluids are compared with speciation calculations and some implications for the assessment of metal mobility and natural attenuation in a context of landfill risk assessment are discussed.  相似文献   

15.
Contaminant transport through the clay liner and the underIying secondary leachate drain layer (SLDL) in landfills was studied through a laboratory test, and analysis method on the transport of K+ in a two-layer soil system. The soils used for this study were Ariake clay and the underlying layer, Shirasu soil from the Kyushu region of Japan, representing the clay liner material and SLDL material, respectively. The effective diffusion coefficients (De) of the selected target chemical species, potassium (K+) for the Ariake clay and Shirasu soil were back-calculated using a computer program, and it was found that values of De derived from this study were consistent with those previously published. The hypothesis that the mechanical dispersion process can be negligible has been proved to be reasonable based on both the observation that the predicted values fit the experimental data and the analyses of two dimensionless parameters. Parametric analysis showed the transport of K+ through the soils is controlled by advection-diffusion rather than diffusion only, whereas at low Darcy velocity (i.e. < or = 10(-9) m s(-1)), transport of K+ would be controlled by diffusion. The test results and parametric analysis may be applied in design of landfill liners and SLDLs, particularly in coastal areas.  相似文献   

16.
As part of the Abatement Strategies for Transboundary Air Pollution (ASTA) research program, the dynamic soil chemistry model SAFE was used to make hindcasts and future projections of soil solution chemistry for 645 Swedish forest soils between 1800 and 2100. The data needed were derived from different databases of different spatial resolution ranging from site-specific measurements of soil and stand characteristics from the Swedish Forest Inventory to species-specific nutrient content ranges based on literature surveys. The time-series of nutrient uptake and atmospheric deposition needed were created using the MAKEDEP model and the future scenarios were based on the 1999 Gothenburg protocol. The version of MAKEDEP used included nutrient content elasticity, and the modelled biomass nutrient content thus varies between regions as well as over time. The results were analysed by dividing the sites into three different regions (southwest, central and north) as well as nationally. It was shown that acidification remains a severe environmental problem in the southwest region even after implementation of the 1999 Gothenburg protocol, whereas in the north the problem is far less pronounced.  相似文献   

17.
Adaptive sampling and analysis programs (ASAPs) provide a cost-effective alternative to traditional sampling program designs. ASAPs are based on field analytical methods for rapid sample turnaround and field-based decision support for guiding the progress of the sampling program. One common objective of ASAPs is to delineate contamination present in soils, either to support feasibility studies or remedial action designs. An ASAP based on portable gas chromatograph/ mass spectrograph (GC/MS) technologies developed at Tufts University combined with decision support tools created at Argonne National Laboratory was used to delineate explosives contamination in soils at Joliet Army Ammunition Plant, Joliet, Illinois. Tufts' GC/MS technologies provided contaminant-specific identification and quantification with rapid sample turnaround and high sample throughput. Argonne's decision support tools estimated contamination extent, determined the uncertainty associated with those estimates, and indicated where sampling should continue to minimize uncertainty. In the case of Joliet, per sample analytical costs were reduced by 75 percent as compared to the cost of off-site laboratory analyses for explosives. The use of an ASAP resulted in a much more accurate identification and delineation of contaminated areas than a traditional sampling program would have with the same number of samples collected on a regular grid. While targeting explosives contamination in soils at Joliet, the ASAP technologies used in this demonstration have much broader application.  相似文献   

18.
This paper discusses two bottom-up models for the estimation of carbon storage and CO2 emissions related to the nonenergy use of fossil energy carriers. The models show how material flow accounting can be applied to policy making. The nonenergy use emission accounting tables model is a static model, while the chemical industry environmental strategy assessment program (CHEAP) model is a dynamic model of the flows of synthetic organic materials. Both models provide detailed and more accurate estimates of carbon storage in materials than the accounting method that is currently used in the framework of the Intergovernmental Panel on Climatic Change (IPCC) guidelines. The results for both models suggest that carbon storage in synthetic organic materials has been overestimated, and consequently CO2 emissions have been underestimated. Japanese CO2 emissions in 1996 were at least 1.9% higher than reported previously. The CHEAP model results indicate that the net carbon storage (storage − emissions in waste incineration) will decrease during the next few decades. This decrease is mainly driven by changing waste management practice. Received: December 8, 2000 / Accepted: August 15, 2001  相似文献   

19.
The service life of many buildings and houses built using asbestos-containing materials is coming to an end and their demolition will lead to a great deal of asbestos-containing waste (ACW). Conventionally, the disposal of such waste is conducted by isolation under controlled landfill procedures; however problems with this method exist, such as the risk at the time of re-utilization of landfill sites and the depletion of lands to be reclaimed. Melting treatment is a promising technology that could be used to solve these problems; a thermal process involving temperatures exceeding the melting points of asbestos, it transforms them into non-hazardous minerals. This technology may be applicable not only for friable ACW but also for nonfriable ACW. We performed a demonstration test of melting treatment of nonfriable ACW using a gasification and melting furnace of the shaft furnace type, which is a typical method for high temperature melting. Detailed observation using transmission electron microscopy as well as general analyses verified that the same level of asbestos remained in the slag obtained by high temperature melting as that of the background soil. In addition, the asbestos concentration in the exhaust gas and the dust from the facility were at sufficiently low levels, and it was thus verified that the asbestos concentration in the atmosphere in the vicinity of the facility during the melting treatment was comparable to that of Japan’s background level reported by the Ministry of the Environment in 2007.  相似文献   

20.
The U.S. Army Corps of Engineers (US ACE) used the Triad approach to expedite site characterization of contaminated soil at the Former Small Arms Evergreen Infiltration Training Range in Fort Lewis, Washington. The characterization was designed to determine if surface soils contain significant concentrations of metals, with the focus on collecting sufficient data for determining appropriate future actions (i.e., risk analysis or soil remediation). A dynamic sampling and analytical strategy based on rapid field‐based analytical methods was created in order to streamline site activities and save resources while increasing confidence in remediation decisions. Concurrent analysis of soil samples during the demonstration of method applicability (DMA) used both field portable X‐ray fluorescence (FPXRF) and laboratory methodologies to establish a correlation between FPXRF and laboratory data. Immediately following the DMA, contaminated soil from the impact berm was delineated by collecting both FPXRF data and fixed laboratory confirmation samples. The combined data set provided analytical results that allowed for revisions to the conceptual site model for the range and directed additional sample collection activities to more clearly determine the extent and distribution of soil contamination. © 2004 Wiley Periodicals, Inc.  相似文献   

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