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1.
A number of studies have so far been conducted to assess the magnitude of pollution generated by domestic and industrial sources in the Istanbul Metropolitan Area. They indicate that a management scheme for wastewater treatment and disposal should involve a total discharge of 15.4 m3 s(-1) with a potential pollution load of 330 tons BOD5 day(-1) for 1990. A scheme of this magnitude inevitably requires careful evaluation of receiving water characteristics, both from an oceanographic and a quality standpoint. In this paper significant water quality parameters related to the Black Sea-Bosphorus Strait-Marmara Sea System are reviewed and incorporated in the evaluation of treatment and disposal alternatives. In this context, the pollution exchange between the Mamara Sea and Bosphorus is quantified, pollutant contents of the Mamara Sea and discharges from the Istanbul Metropolitan Area are compared, and a number of scenarios are evaluated to define the optimum treatment and disposal strategy.  相似文献   

2.
Environmental Science and Pollution Research - Biomass waste contributes 14% of the total global energy. And 15–20% of the coal-fine waste from coal mines are deposited in the rivers, ponds,...  相似文献   

3.
Combustion of coal, oil, and natural gas, and to a lesser extent deforestation, land-cover change, and emissions of halocarbons and other greenhouse gases, are rapidly increasing the atmospheric concentrations of climate-warming gases. The warming of approximately 0.1-0.2 degrees C per decade that has resulted is very likely the primary cause of the increasing loss of snow cover and Arctic sea ice, of more frequent occurrence of very heavy precipitation, of rising sea level, and of shifts in the natural ranges of plants and animals. The global average temperature is already approximately 0.8 degrees C above its preindustrial level, and present atmospheric levels of greenhouse gases will contribute to further warming of 0.5-1 degrees C as equilibrium is re-established. Warming has been and will be greater in mid and high latitudes compared with low latitudes, over land compared with oceans, and at night compared with day. As emissions continue to increase, both warming and the commitment to future warming are presently increasing at a rate of approximately 0.2 degrees C per decade, with projections that the rate of warming will further increase if emission controls are not put in place. Such warming and the associated changes are likely to result in severe impacts on key societal and environmental support systems. Present estimates are that limiting the increase in global average surface temperature to no more than 2-2.5 degrees C above its 1750 value of approximately 15 degrees C will be required to avoid the most catastrophic, but certainly not all, consequences of climate change. Accomplishing this will require reducing emissions sharply by 2050 and to near zero by 2100. This can only be achieved if: (1) developed nations move rapidly to demonstrate that a modem society can function without reliance on technologies that release carbon dioxide (CO2) and other non-CO2 greenhouse gases to the atmosphere; and (2) if developing nations act in the near-term to sharply limit their non-CO2 emissions while minimizing growth in CO2 emissions, and then in the long-term join with the developed nations to reduce all emissions as cost-effective technologies are developed.  相似文献   

4.
简易水处理活性炭的选择和应用方法   总被引:18,自引:11,他引:7  
首先介绍活性炭性能测试与水处理活性炭选炭、吸附技术选择、工艺应用的关系,其次报导两个活性炭选用方面的改进方法。通过重新定义、整合、完善现有活性炭性能指标,建立了以酚值、碘值、亚甲基蓝、丹宁酸值为吸附性能指标的选炭方法。这四种指标化合物的分子量与直径覆盖了大多数有机污染物的范围,用此法可减少活性炭应用测试的炭型。在活性炭精选和吸附工艺应用研究中,用微型炭柱进行穿透实验可弥补缩小式传统型、小型炭柱的不足。相对于国外现用微型柱的实验方法,文中介绍的微型柱快速穿透(MCRB)方法的设备要求较低,操作简单,可以在国内大多数实验室中进行;遇过对多种污染物质的实验结果,建立了MCRB方法的可信性和适用性。这两种新方法完善了活性炭水处理研究的实验体系,可降低其应用于水与污水处理的成本,有利于中国的环境保护。  相似文献   

5.
Abstract

Combustion of coal, oil, and natural gas, and to a lesser extent deforestation, land-cover change, and emissions of halocarbons and other greenhouse gases, are rapidly increasing the atmospheric concentrations of climate-warming gases. The warming of approximately 0.1–0.2 °C per decade that has resulted is very likely the primary cause of the increasing loss of snow cover and Arctic sea ice, of more frequent occurrence of very heavy precipitation, of rising sea level, and of shifts in the natural ranges of plants and animals. The global average temperature is already approximately 0.8 °C above its preindustrial level, and present atmospheric levels of greenhouse gases will contribute to further warming of 0.5–1 °C as equilibrium is re-established. Warming has been and will be greater in mid and high latitudes compared with low latitudes, over land compared with oceans, and at night compared with day. As emissions continue to increase, both warming and the commitment to future warming are presently increasing at a rate of approximately 0.2 °C per decade, with projections that the rate of warming will further increase if emission controls are not put in place. Such warming and the associated changes are likely to result in severe impacts on key societal and environmental support systems. Present estimates are that limiting the increase in global average surface temperature to no more than 2–2.5 °C above its 1750 value of approximately 15 °C will be required to avoid the most catastrophic, but certainly not all, consequences of climate change. Accomplishing this will require reducing emissions sharply by 2050 and to near zero by 2100. This can only be achieved if: (1) developed nations move rapidly to demonstrate that a modern society can function without reliance on technologies that release carbon dioxide (CO2) and other non-CO2 greenhouse gases to the atmosphere; and (2) if developing nations act in the near-term to sharply limit their non-CO2 emissions while minimizing growth in CO2 emissions, and then in the long-term join with the developed nations to reduce all emissions as cost-effective technologies are developed.  相似文献   

6.
7.
Kao CM  Chen SC  Su MC 《Chemosphere》2001,44(5):925-934
The industrial solvent trichloroethylene (TCE) is among the most ubiquitous chlorinated compounds found in groundwater contamination. The objective of this study was to develop a biobarrier system containing oxygen-organic releasing material to enhance the aerobic cometabolism of TCE in situ. The oxygen-organic material, which contains calcium peroxide and peat, is able to release oxygen and primary substrates continuously upon contact with water. Batch experiments were conducted to design and identify the components of the oxygen-organic releasing material, and evaluate the oxygen and organic substrate (presented as COD equivalent) release from the designed oxygen-organic material. The observed oxygen and chemical oxygen demand (COD) release rates were approximately 0.0246 and 0.052 mg/d/g of material, respectively. A laboratory-scale column experiment was then conducted to evaluate the feasibility of this proposed system for the bioremediation of TCE-contaminated groundwater. This system was performed using a series of continuous-flow glass columns including a soil column, an oxygen-organic material column, followed by two consecutive soil columns. Aerobic acclimated sludges were inoculated in all three soil columns to provide microbial consortia for TCE biodegradation. Simulated TCE-contaminated groundwater with a flow rate of 0.25 l/day was pumped into this system. Effluent samples from each column were analyzed for TCE and other indicating parameters (e.g., pH, dissolved oxygen). Results show that the decreases in TCE concentrations were observed over a 4-month operating period. Up to 99% of TCE removal efficiency was obtained in this passive system. Results indicate that the continuously released oxygen and organic substrates from the oxygen-organic materials enhanced TCE biotransformation. Thus, the biobarrier treatment scheme has the potential to be developed into an environmentally and economically acceptable remediation technology.  相似文献   

8.

Purpose  

Tannins and dyes pose major threat to the environment by generating huge pollution problem. Biodegradation of wattle extract, chrome tannin and dye compounds using suitable fungal culture namely Aspergillus niger, Penicillium sp. were carried out. In addition to these, ozone treatment was carried out to get higher degradation rate.  相似文献   

9.
10.
微电解工艺研究进展   总被引:10,自引:5,他引:5  
本文探讨了微电解工艺的基本原理和反应机理 ,总结了该工艺的设计参数、优缺点 ,并概述了该工艺在电镀、染料、石油化工等工业废水治理中的应用现状。我国对微电解工艺从 2 0世纪 80年代研究至今 ,已在各个行业有了广泛的应用。从实际应用来看 ,该工艺具有适用范围广、处理效果好、使用寿命长、成本低廉等优点 ,具有良好的工业应用前景。但同时也出现了结块等问题。  相似文献   

11.
Sediment quality guidelines (SQGs) assess the ability of bottom sediment to sustain healthy infauna and water quality guidelines (WQGs) provide protection for a designated percentage of aquatic species. Filter-feeding marine species, e.g. oysters and mussels, acquire food from particles in the water column and protection of these animals is not provided by SQGs or WQGs. The current work investigated the relationship between metal (Cu, Zn) concentrations in total and fine-fraction (<62.5 μm) surficial sediment digested in a range of acids and chelating agents and oyster tissue metal concentrations. A strong correlation between oyster tissue Cu and Zn concentrations and fine-fraction surficial sediment digested in 1 M HCl provided a sedimentary guideline which predicted tissue metal concentrations in oysters and established a level (<45 μg g−1 and <1000 μg g−1, respectively) for protecting oysters from exceeding human consumption levels (70 μg g−1 and 1000 μg g−1, respectively).  相似文献   

12.
M Horvat 《Chemosphere》1999,39(7):1167-1179
A good quality control/quality assurance programme should be implemented in all environmental or health related studies on mercury and its organic compounds, particularly, for monomethylmercury (MeHg) which is the most toxic mercury compound. This can be achieved initially by analysing suitable certified reference materials (CRMs), which are available from various producers such as the National Institute of Standards and Technology (NIST) from USA, National Institute of Environmental Studies (NIES), National Research Council of Canada (NRCC), Standards, Measurements and Testing programme (SM&T) of the European Commission, and the International Atomic Energy Agency (IAEA). It is well understood that these materials are not covering present needs, as most of them are of the marine origin, while many laboratories are conducting research and monitoring in terrestrial ecosystems and fresh water environment. In addition, CRMs for human exposure assessment, such as blood, urine, and hair at several levels of concentrations are still lacking. Therefore, many other actions should be undertaken to achieve, improve and/or maintain quality of data, including participation in interlaboratory studies, proficiency testing and production of laboratory reference materials. A review of these actions has shown that MeHg compounds determination in samples such as soil, sediment and water is rather difficult and the results are also method dependent. In addition, it has been shown that some of the most frequently employed analytical methods may be a subject to spurious MeHg formation in the presence of high concentrations of inorganic mercury and organic matter. These findings have put a number of previous data on MeHg in question and consequently prompt actions were undertaken by a number of well experienced laboratories and producers of CRMs. So far, it is shown that the results obtained by various laboratories using different analytical techniques agree well with certified values in all RMs certified for MeHg. This suggests that comparability of data can be achieved, which however is not a guarantee of the true values.  相似文献   

13.
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16.
Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorganic, or hybrid materials for light collection and catalysis. We also briefly discuss challenges and needs for large-scale implementation of direct solar fuel technologies.  相似文献   

17.
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19.
Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l−1 range, some active metabolites could be present at higher concentrations, although limited data on metabolism and environmental fate limit the relevance of PECs. The biological effects are not expected to be restricted to progestagenic activity. Both anti-androgenic activity (mainly for cyproterone acetate, chlormadinone acetate and their metabolites) and estrogenic activity (mainly for reduced metabolites of levonorgestrel and norethisterone) should also occur. All these molecules are likely to have a cumulative effect among themselves or with other xenoestrogens. Studies on occurrence, toxicity and degradation time are therefore needed for several of these compounds.  相似文献   

20.
Yazgan MS  Wilkins RM  Sykas C  Hoque E 《Chemosphere》2005,60(9):1325-1331
Predicting the fate and transport of pesticides in soil environment is an important issue especially in understanding and modelling of the environmental behaviour of pesticides. Classical batch sorption method often has been identified as insufficient to derive the actual extent of sorption. In this study, the batch equilibrium method was compared to the centrifugation method, which can permit measurement of sorption under more natural conditions. The results of the comparison of the batch with the centrifugation method for imidacloprid and carbofuran pesticides indicate that the batch method overestimates sorption in comparison to the centrifugation method. These results are in agreement with others, which use high soil:solution ratios with batch and those that used the centrifugation method.  相似文献   

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