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1.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   

2.
Kizildere, which is the only commercial geothermal power plant in Turkey and located in Buyuk Menderes Graben in south-west Turkey, discharges annually 6 million tonnes of wastewater into the Buyuk Menderes river, creating environmental pollution. Currently, the wastewater, which includes up to 24 mg/l boron, is discharged into the river at a rate of 750–1500 tonnes per hour. The temperature of the wastewater is approximately 1401°C. The water quality of Buyuk Menderes river is very important for the environment and aquatic life. Reinjection seems to be the only possible solution to this environmental problem.  相似文献   

3.
As the Korean national economy has continued to grow and the industrial structure has become increasingly advanced, the amount of wastes being generated is rapidly on the rise. Recycling to cope with the environmental problems caused by wastes has become an increasingly important policy issue in developing countries such as Korea, as well as in developed countries. To provide policy-makers with practical and responsible analysis regarding the role of the national recycling utility in the economy, this study employed input–output (I–O) analysis with specific application to Korea. The major goal was the development of a static I-O framework for examining the role of the national recycling utility in the short run. The second goal was to obtain at least a preliminary indication of the role of the national recycling utility. This paper also discusses the role of a public firm that was established with an objective of promoting and facilitating the reuse of recyclable wastes. The overall results indicate that the national recycling utility may have a significant influence on the standard of living and industrial production.  相似文献   

4.
The dye and dye intermediaries industry is an important segment of the chemical industry that provides inputs to a large number of industries. Currently, the Indian dyestuff industry is in the midst of a major restructuring and consolidation phase. With the emphasis on product innovation, rebuilding and environmental friendliness, this industry is increasingly moving towards greater customer orientation. Given the dynamic nature of the dyestuff industry in India and its tremendous potential, this study aims to conduct an economic analysis of the industry, with specific reference to its inherent environmental problems. The scope of the study was limited to a study of some units in Ranaghat, a town in the Nadia district of West Bengal. The potential environmental problems and the health hazards arising as results of dyes and dye production have been investigated. A case study of a dyeing unit in Ranaghat is presented, highlighting the negative impact on the water quality of its adjoining river, followed by some suggestions on ways of handling the pollution problem. A cost–benefit analysis of a dyeing unit in Ganganagar, and application of the results to the dyeing industry in Ranaghat, is also reported. The study also suggests some policies for consideration.  相似文献   

5.
This paper describes the main features of the study 'Natural Resources and Environmental Accounting in the Czech Republic' (NREACR), carried out under the Phare programme during 1998—1999. Within the project, five major methodological areas were specified: NAMEA-type accounting; land cover/land use (LC/LU) accounting; abatement cost curves (air—energy, transport and industry; water—agriculture, industry, housing); economic (monetary) appraisal of natural assets; and dynamic modelling and scenario development. The results of the first four modules can be thought of as elements of a policy support databank that can have many uses, including the information inputs needed for national economy scenario modelling aimed at exploring the potentials, constraints and trade-oils in the setting and evaluation of Czech Republic economic and environmental policy. In this paper, an overview is given of the modular approach adopted for economy—environment accounting and of the main results, followed by discussion of the outlook for further work in the field in the Czech Republic and also potentially for other EU Accession countries.  相似文献   

6.
Weekend air quality is analysed with the aid of Fourier analysis, in order to reveal time-series structures for Athens, Greece. For this reason, an appropriate analysis of a 10 year record from 1990–1999 of air quality data from the monitoring network in Athens is carried out for two specific monitoring sites. The aim of the paper is to investigate the temporal pattern of observations in order to reveal relations and trends. Thus, it is expected that the estimation of environmental consequences related to various incentives aimed at the reduction of air emissions will be enriched. The aim of the current work is also to demonstrate that the analysis of weekend air quality monitoring data records is an appropriate method for estimating the temporal variation of air pollution in urban agglomerations, based on appropriate approximations.  相似文献   

7.
In the present paper, analytical expressions are derived for the below-cloud gas scavenging coefficient, considering various functions that can be found in the literature to describe raindrop populations and terminal velocities. Three primary cases have been identified where an analytical solution exists: (i) a raindrop size distribution described by a gamma function and raindrop terminal velocity by a power function of raindrop size; (ii) a raindrop size distribution described by a gamma function and raindrop terminal velocity by an exponential function; and (iii) a raindrop size distribution described by a log–normal function and raindrop terminal velocity by a power function. In addition, in case (i), the gas scavenging coefficient is expressed analytically as a function of rain intensity. The derived analytical expressions are subsequently used to compute the scavenging coefficients of HNO3 for different parameterizations of the raindrop size distribution and terminal velocity functions. In order to broaden the sensitivity test of HNO3 scavenging coefficients on parameterizations, scavenging coefficients of HNO3 are also computed numerically for the raindrop terminal velocity as a function of raindrop size and atmospheric conditions. The results show that there is a relative variation in the values of the gas scavenging coefficient up to 50% for the parameterization considered in this study, and that the overestimation given by the analytical formulas is not important for cut-off limits of raindrop spectra below 0.2 mm.  相似文献   

8.
We present a material flow analysis (MFA) of biological oxygen demand (BOD5) and suspended solids (SS) in estuaries located on the northern and southern coasts of Taiwan. Using data from 1992–2000, we examine human economic activities in each watershed to predict associated pollutant flows. This estimate is compared to data collected at monitoring stations. The ratio allows us to calculate each river system's ability to assimilate and decompose these pollutants, its self-purification capacity. Our results show that over six times as much BOD5 reaches the northern estuary from the urban watershed that in the south. More SS reaches the southern estuary than the north due to more intense land disturbance. Trends for pollutant flows to the northern estuary threaten its capacity to meet sustainability criteria. Trends in the south show a receding threat. We suggest management objectives to enhance prospects for sustaining environmental quality in these two critical regions.  相似文献   

9.
Biotic and abiotic transformations of methyl tertiary butyl ether (MTBE)   总被引:1,自引:0,他引:1  
Background Methyl tertiary butyl ether (MTBE) is a fuel additive which is used all over the world. In recent years it has often been found in groundwater, mainly in the USA, but also in Europe. Although MTBE seems to be a minor toxic, it affects the taste and odour of water at concentrations of < 30 μg/L. Although MTBE is often a recalcitrant compound, it is known that many ethers can be degraded by abiotic means. The aim of this study was to examine biotic and abiotic transformations of MTBE with respect to the particular conditions of a contaminated site (former refinery) in Leuna, Germany. Methods Groundwater samples from wells of a contaminated site were used for aerobic and anaerobic degradation experiments. The abiotic degradation experiment (hydrolysis) was conducted employing an ion-exchange resin and MTBE solutions in distilled water. MTBE, tertiary butyl formate (TBF) and tertiary butyl alcohol (TBA) were measured by a gas chromatograph with flame ionisation detector (FID). Aldehydes and organic acids were respectively analysed by a gas chromatograph with electron capture detector (ECD) and high-performance ion chromatography (HPIC). Results and Discussion Under aerobic conditions, MTBE was degraded in laboratory experiments. Only 4 of a total of 30 anaerobic experiments exhibited degradation, and the process was very slow. In no cases were metabolites detected, but a few degradation products (TBF, TBA and formic acid) were found on the site, possibly due to the lower temperatures in groundwater. The abiotic degradation of MTBE with an ion-exchange resin as a catalyst at pH 3.5 was much faster than hydrolysis in diluted hydrochloric acid (pH 1.0). Conclusion Although the aerobic degradation of MTBE in the environment seems to be possible, the specific conditions responsible are widely unknown. Successful aerobic degradation only seems to take place if there is a lack of other utilisable compounds. However, MTBE is often accompanied by other fuel compounds on contaminated sites and anaerobic conditions prevail. MTBE is often recalcitrant under anaerobic conditions, at least in the presence of other carbon sources. The abiotic hydrolysis of MTBE seems to be of secondary importance (on site), but it might be possible to enhance it with catalysts. Recommendation and Outlook MTBE only seems to be recalcitrant under particular conditions. In some cases, the degradation of MTBE on contaminated sites could be supported by oxygen. Enhanced hydrolysis could also be an alternative. - * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August to 1 September 2004, Bordeaux, France.  相似文献   

10.
Based on previous theoretical work by Gottinger (1997, 1998), we propose a simple model of optimal monitoring of oil-related activities in harbour areas that is suitable for empirical estimation within the Russian— Ukrainian context, in spite of the poor availability of data in these countries. Specifically, the model indicates how to best allocate at the steady state a given monitoring budget between different monitoring activities. An approximate analytical solution to the optimisation problem is derived, and a simple procedure for estimating the model on the basis of the actually available data is suggested. An application using data obtained for several harbours of the Black and Baltic Seas is given. It suggests that the current Russian monitoring practice could be much improved by better allocating the available monitoring resources.  相似文献   

11.
Slippery Rock University's Macoskey Center for Sustainable Systems has served as an ideal locale for the study of biological waste and wastewater concerns in Western Pennsylvania. The Center's constructed ponds, waterless composting toilet and indoor greywater treatment system produced, in 1998–2000, great amounts of data on ecological approaches to wastewater treatment, which need to be reviewed. In particular, the study of these three separate systems widens the understanding of the different mechanisms needed to treat wastewater of different levels of contamination. Research and development was done in 1998–2004 to explore sustainable approaches to small-scale residential wastewater issues when a constructed wetland is built at the Center.  相似文献   

12.
- DOI: http://dx.doi.org/10.1065/espr2006.01.295 Background Many organic micropollutants occur at trace concentrations in municipal wastewater effluents and in the aquatic environment. Some of these xenobiotic chemicals can be considered as 'emerging' contaminants and some are suspect to have endocrine disrupting effects. Among the latter are nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), which deserve special attention due to their ubiquitous occurrence in the aquatic environment. The complexing agents benzotriazole (BT) and tolyltriazole (TT) are applied as anticorrosive agents (e.g. in cooling and hydraulic fluids, in antifreezing fluids, in aircraft deicing fluids, in dish washing liquids for silver protection), as antifogging agents and as intermediates for the synthesis of various chemicals. The environmental occurrence of NP and OP is caused by the fact that they are intermediate products (metabolites) in the biodegradation of alkylphenol polyethoxylate surfactants. BPA is globally used for the production of polycarbonate and epoxy resins. Methods BT, TT, NP, OP and BPA were quantitatively determined in municipal wastewater effluents in Switzerland and in the Glatt River. The analytes were enriched by solid-phase enrichment. BT and TT were determined underivatized by electrospray LC/tandem MS. Reversed-phase LC was performed on octylsilica columns with isocratic water/methanol elution. Multiple reaction monitoring of the positive ions provided selective and sensitive detection for reliable quantifications. NP, OP and BPA were determined by GC/MS after derivatization with N-methyl-N-(trimethylsilyl)-trifluoroacetamide. Results and Discussion BT and TT concentrations in primary and secondary effluents of municipal wastewater treatment plants varied from below 10 to 100 μg/L. The ranges of the concentrations in the Glatt River in ng/L were 636–3,690 for BT, 122–628 for TT, 68–326 for NP, 6–22 for OP and 9–76 for BPA. The corresponding mass flows in g/d were 93–1,870 for BT, 18–360 for TT, 24–183 for NP, 1–16 for OP and 2–72 for BPA. The concentrations and mass flows of NP in the River Glatt were drastically lower than the analogous values found 15 years ago. Thus, a substantially decreased environmental exposure can be observed due to the reduction of the use of alkyphenol polyethoxylate surfactants in Switzerland. The current concentrations of NP, OP and BPA are within the ranges reported for weakly impacted surface waters. Conclusion The investigated contaminants occur at quantitatively measurable but varying concentrations in municipal wastewaters and in the Glatt River reflecting their ubiquitous input into wastewaters and their different behaviour during biological wastewater treatment.  相似文献   

13.
Reducing greenhouse gas (GHG) emissions to avert or slow climate change has become an increasingly important policy issue in developing countries such as Korea, as well as in developed countries. This paper uses the willingness to pay survey technique to assess the benefits that would ensue from a proposed OHO emissions reduction policy. It aims to provide at least a preliminary evaluation of the policy, using Korea as a specific case study. Respondents overall accepted the contingent market and were on average willing to contribute a significant amount toward the GHG emissions reduction policy. This willingness varies according to respondents' individual characteristics and environmental concerns. Finally, this study discusses the importance of including the climate change problem in cost—benefit analysis and presents the policy implications of the results.  相似文献   

14.
The scaling behaviour in acid deposition dynamics of 184 monitoring sites under the National Atmospheric Deposition Program (NADP) is analysed for the 1978–2001 period. The results show that: the distribution of weekly hydrogen deposition (WHD) is consistent with a power law in two different regimes separated by a crossover WHD (CWHD), and both the CWHD and its probability density increase as the power law commensurate with the mean of WHD series; the distribution of pH values shows a series behaviour similar to that of WHD and can be depicted as a log–linear model with the same form of Gutenberg–Richter model of earthquake occurrence; and the successive time-duration (weeks) of both acid and non-acid rain also obeys a power law, with the average duration of acid rain scaling as a positive power law and that of non-acid rain as a negative power law of average WHD. The power laws in the acid deposition dynamics are considered to be indicators of self-organisation of the atmosphere under environmental pollution stress.  相似文献   

15.
A new approach is proposed to the numerical solution of one-dimensional convection–diffusion equations that arise in modelling atmospheric processes and air pollution modelling. The technique is based on upstream-type difference approximations for first-order derivatives and non-standard difference approximations for second-order derivatives of convection–diffusion equations. This approach leads to the significant qualitative improvements in the numerical solutions behaviour. The relative contribution of convection and diffusion is directly incorporated into the corresponding numerical scheme in such a way that large spatial grids can be taken without affecting solution stability. The method is compared with the contemporary computational schemes for solving problems with severe internal and boundary gradients and is shown to be stable and computationally efficient. The results of a numerical experiment are given.  相似文献   

16.
- DOI: http://dx.doi.org/10.1065/espr2006.01.014 Background, Aims and Scope Triazole-derivatives are potent antifungal agents used as systemic agricultural fungicides and against fungal diseases in humans and domestic animals. They act by inhibiting the cytochrome P-450 conversion of lanosterol to ergosterol, thus resulting in faulty fungal cell wall synthesis. Some data have been published about the teratogenic activity of triazoles on rodent embryos: Hypoplasias, abnormal shape, agenesis of the branchial arches, for example, were reported as typical induced malformations. Unfortunately, no data are available on the embryotoxicity of these compounds in amphibians, despite the increasing concern among the scientific community about the phenomenon of global amphibian population declines. The aim of the present work is to evaluate the embryo-lethal and teratogenic potentials of Triadimefon (FON), a triazolederivative widely used as an antimycotic in agriculture, by the test FETAX (Frog Embryos Teratogenic Assay, Xenopus) with particular attention being paid to the analysis of branchial arch malformations. Methods Xenopus laevis embryos were exposed continuously from stage 9 to increasing concentrations of FON and analyzed at stage 47 for mortality and teratogenicity (group I) to determine the median lethal (LC50) and teratogenic (TC50) concentrations. Another two pools of larvae were exposed to FON for a 2 hour period at early gastrula (Group II) or neurula (Group III) stages to verify which period of development is the most sensitive to FON. The malformations observed were further investigated by histological section and cartilage staining with Alcian blue. Results and Discussion The assay has estimated LC50 and TC50 values of 63.8 μM and 2.73 μM, respectively; the resulting TI (Teratogenic Index = LC50/TC50) value of 23.4 has underlined the very high teratogenic risk associated with this compound. Neurulation was more sensitive to FON exposure than gastrulation, since the TC50 estimated values for group III (neurula exposed) specimens was 7.6 times lower than those of group II (gastrula exposed). Interestingly, for each group analyzed, 100% of malformed embryos showed alterations at branchial arch derived cartilages: Anterior cartilages were reduced, missing, fused or incorrectly positioned while gill cartilages were altered only in the most severely affected specimens. In some cases these malformations were associated with hyperpigmentation. Our results support the hypothesis that FON can interfere with Neural Crest Cell (NCC) migration, since craniofacial components and melanophores are derived from neural crest material. Conclusion In conclusion, our data show Triadimefon to be a potent teratogen able to induce specific craniofacial malformation in Xenopus laevis embryos, probably interfering with the NCC migration into the branchial mesenchyme. These results are also interesting for ecotoxicological reasons as FON, as well as other pesticides, are likely to be present in water systems near agricultural or urban areas which may serve as habitats for developing amphibians and fishes. Recommendation and Outlook Our results are in agreement with the data obtained on in vitro cultured rat embryos suggesting that the FON mechanism of action involves strongly conserved molecules. The choice of Xenopus laevis as the model organism allows us to extend the toxicological and teratological observations to a molecular level, in order to search for novel genes regulated by FON exposure.  相似文献   

17.
A detailed characterisation of the incoming wastewater and a performance evaluation were carried out for the domestic wastewater treatment plant of Erzincan City. Conventional characterisation results showed that Erzincan has a medium strength wastewater quality. Structural characterisation of the chemical oxygen demand (COD) indicated that the biodegradable fraction of the total COD was 64.7%. The soluble inert fraction was computed as 10.9% of the total COD. In Erzincan, an activated sludge plant provides secondary treatment using Carrousel treatment units. Because some operational problems, such as sludge bulking and foaming, have been experienced, and performance failures related to carbonaceous matter removal have been recorded many times, a new operational strategy suitable for this type of treatment plant was developed. In the new strategy, the sludge age was kept at 22 days, intermittent aeration was abandoned and replaced by continuous aeration, and the sludge recycle ratio was increased to 1.35 from 0.85. The developed operational strategy showed its merit in that previous operational problems largely disappeared and COD concentrations remained below the Turkish discharge limits of 100 mg/l and the NH4 removal rate was in the range 87–95%.  相似文献   

18.
Air quality in cities is the result of a complex interaction between natural and anthropogenic environmental conditions. Delhi, as well as many other cities in India, is facing problems concerning air pollution. The increase in industrialisation and the vehicle fleet, poor control on emissions and little use of catalytic converters, produce a great amount of particulate and toxic gases. Data on air pollutants and meteorological variables were collected in the metropolitan cities Delhi, Kolkata, Mumbai and Chennai for the period July–August, 2001. Data were treated with the bivariate regression model to explore the influence of the meteorological variables on air pollutant concentrations, and were also used to compute an Air Quality Index, using the weighted arithmetic mean method. The proposed index seems to be applicable in the assessment of overall air quality with respect to air pollutants.  相似文献   

19.
Chemical ionisation mass spectrometry (CI-MS) was applied to study the benzene emission characteristics of a TWC-vehicle at a time resolution of one Hertz. Three important operating conditions with increased emissions were identified: at vehicle start; at extended stop-and-go situations; and whenever a catalyst-induced benzene formation occurs. The cold start influence was detectable for about 200 seconds of driving corresponding to a distance of 1.2 km. At hot engine/catalyst mean pre- and post-catalyst emission rates of 25–150 mg km-1 and 0.1–135 mg km-1 were determined. Catalyst conversion varied from 0.07 to >0.99. Even negative conversion efficiencies were observed at several occasions, indicating that benzene can be formed de novo in a TWC. It is of importance to lower benzene emissions at these critical operating conditions to further reduce ambient air levels in cities and with it the cancer risk for large proportions of our population.  相似文献   

20.
This study was carried out on two field scale test cells constructed at Odayeri Sanitary Landfill (OSL) located at the European side of Istanbul city. Approximately 11,000 tons of municipal solid wastes (MSW) were filled at equal quantities to each cell (C1 and C2). Leachate was periodically recirculated to one (C2) of the test cells in various quantities. These cells are compared in terms of leachate quality (pH, BOD and COD), methane potential (MP) of wastes and surface settlement for a monitoring period of 0–400 days. Experimental results showed that optimum pH for anaerobic decomposition was reached in a shorter period of time in C2 compared to C1. Moreover, BOD and COD concentrations were decreased more rapidly in C2 cell than in C1 cell. BOD/COD ratio was determined as 0.25 and 0.17 for C1 and C2 cells consequently after 380 days from placement of refuse to the test cells. In MP tests, first order rate constants for cell C1 and C2 were found be 0.145 year-1 and 0.222 year-1, respectively. Topographic measurements revealed that cumulative settlements after 12 months from refuse placement were 0.49 and 0.70 m for C1 and C2 cells, respectively. According to results obtained from this study, it can be concluded that appropriate conditions can cause enhance in the decomposition rate of MSW.  相似文献   

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