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1.
ABSTRACT

In power grids, a significant amount of the generated power in power plants is wasted in the grid between power plants and consumers. The amount depends on different factors. With regard to the vital role of electricity in economic and social development alongside with high investment costs in electricity generation, transmission and distribution, practical solutions for decreasing grid losses and enhancing the efficiency of existing facilities are crucial. Due to the global environmental situation and significant effects of energy consumption on the environment, the general trend is towards the deployment of methods which are more efficient and less fuel consuming. In addition, more implementation of monitoring and controlling equipment and instalment of more efficient equipment in electricity transmission and distribution sectors reveal the effort towards the reduction of pollutants. These facts reveal the importance of this issue amongst authorities in the power industry. In this research through the assessment of power grid losses and studying different types of power plants in Iran, the amount of electricity generation and grid loss are studied. In addition, the impact of different power plants on the amount of environmental pollutants especially CO2 is presented. Also, some solutions to reduce CO2 emission are provided.  相似文献   

2.
Water supply is a core service on which civilised society depends. It involves considerable energy consumption, CO2 emissions and costs. As such, scientific efforts in the water industry in recent years have focused on improving the sustainability of water supply. This paper examines the potential for energy recovery in the water industry which may be exploited through the use of mini or micro‐hydropower installations. A case study of water infrastructure in Ireland is included in the analysis to highlight the potential of this concept in practice. The results of this investigation show that in certain circumstances significant energy, environmental and economic savings are available with modest investment.  相似文献   

3.
Reducing greenhouse gas (GHG) emissions involves effort from different sectors of the economy, including the water and sewerage industry. This study estimates the marginal cost of curtailing GHG emissions in the water and sewerage industry using stochastic frontier analysis techniques for a sample of ten English and Welsh water and sewerage companies over the 2010–2019 period. Results illustrated that the average marginal cost of reducing GHG emissions was 0.181 £/Kg CO2 equivalent. The marginal cost estimated notably differs across companies and over time. Findings further illustrate the impact of water companies' operating characteristics on the marginal cost of reducing carbon emissions.  相似文献   

4.
随着现代工业的迅速发展,生产过程中排出的有害重金属离子废水、印染废水等日益增加,寻找更为高效的水处理材料成为环境保护中亟待解决的问题。磁性壳聚糖微球是一种新兴的水处理吸附剂,对多种污染物都具有优良的吸附效果,再加上可回收重复利用的特点,受到了广泛关注。对磁性壳聚糖微球进行改性,可赋予它不同的功能特性。综述了不同交联剂制备磁性壳聚糖微球的研究现状,分别介绍了对壳聚糖外壳和Fe_3O_4磁核的改性方法、机理及其应用,并对磁性壳聚糖微球未来的研究趋势进行了展望。  相似文献   

5.
6.
Phosphogypsum (CaSO4·2H2O), a by-product of phosphate-rock processing, contains high amounts of impurities such P2O5, F, radioactive elements, organic substances, secondary nanominerals, and ultrafine particles (UFP) enriched in metals and metalloids. In this study, we examine phosphogypsum (PG) collected from abandoned fertilizer industry facility in south Brazil (Santa Catarina state). The fragile nature of nanominerals and UFP assemblages from fertilizer industry systems required novel techniques and experimental approaches. The investigation of the geochemistry of complex nanominerals and UFP assemblages was a prerequisite to accurately assess the environmental and human health risks of contaminants and cost-effective chemical and biogeological remediation strategies. Particular emphasis was placed on the study and characterization of the complex mixed nanominerals and UFP containing potentially toxic elements. Nanometer-sized phases in PG were characterized using energy-dispersive X-ray spectrometer (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) images. The chemical composition and possible correlations with morphology of nanominerals and UFP, as well as aspects of nanominerals and UFP, are discussed in the context of human health exposure, as well as in relation to management of the nanominerals and UFP in PG environments.  相似文献   

7.
Understanding the complex impact of air pollution is crucial to assessing exposure risk and defining public health policies in China. However, the evidence and hence knowledge of how urban activity responds to air pollution are limited. In this paper, we propose to use geotagged check-in records on Weibo, a Tweeter-like platform, to systematically investigate the effect of air pollution on urban activity.Based on panel models, we found clear evidence that such effect exists and varies between pollutants, visitors and residents, and different activity types. Typically, SO2 has the largest impact, followed by PM2.5, NO2, and PM10; local citizens' activities are more susceptible than visitors; leisure-related activity has a sensitivity at least twofold higher than work-related activities. Additionally, we tested hypotheses about the heterogeneous effect. We confirmed the role of Income and air quality, showing that people who live in richer and more polluted cities are more likely to experience the effects of air pollution. Specifically, people who live in a more polluted city with 100 unit increments in AvgAQI show on average the same sensitivity as those who live in a less polluted city and earn about 20.3 thousand yuan more in average Income.This reveals new insights about environmental injustice in China. By presenting a portrait of the spatial heterogeneity, we argued that environmental injustice in terms of air pollution is not just about the difference in exposure risk measured based on population distribution, rather the measurement should also consider the disparity derived from urban activity. Secondly, new injustice may arise in underdeveloped areas where manufacture industry is transferred to but people barely take avoidance behavior. Finally, the map also reveals the general neglect of the detrimental effect of light air pollution, which we speculate is partly due to China's comparatively low standard in governmental regulations.We believe our finding contributes significantly to exposure risk assessment and environmental justice debates. Hence it highlights the necessity and urgency of public healthy polices that spread the health consequence of air pollution, especially in the underdeveloped region.  相似文献   

8.
Road transportation plays a major role in the economic and social development of a country. With the increase in vehicle population, noise levels will increase. This paper discusses the results of a study undertaken to assess the noise levels at the major traffic junctions of an urban city. The noise equivalent level L eq was measured in the community areas as well as at the traffic junctions. The statistical levels L10, L50, L90 were also measured to determine the Traffic Noise Index at the junctions. A holistic approach was adopted to study the impact of noise on the community and at the work place of an industry.  相似文献   

9.
The aim of the present study was to identify the main sources contributing to the air pollution of three indoor environments of different use: a museum, a printery industry and an office. For that purpose, particulate matter (TSP, PM10, PM2.5), inorganic pollutants (NOx, SO2, O3) and organic compounds (BTX, formaldehyde) were monitored. Factors such as the kind of the activities occurred indoors, the emissions from the existing equipment, the number of occupants, the ventilation pattern and the outdoor background substantially varied among the three sites.  相似文献   

10.
《Soils and Foundations》2009,49(3):391-395
The critical state friction angle, φc, is a parameter of interest in many geotechnical analyses dealing with cohesionless soils. However, despite the triaxial test being widely used to estimate this parameter, the accuracy achievable from a limited number of triaxial tests is unknown. Accuracy is of particular interest in industry, where typically only a few soil tests are possible due to budget limitations. Statistical analysis of an extensive high quality triaxial testing program from the literature is used here to obtain guidance on the number, density range, and pressure range of triaxial tests required to reach a specified level of confidence in the critical state friction angle. The adequacy of the estimating methodology is then tested against a smaller and independent set of triaxial tests on the same sand, performed in a commercial testing laboratory. The results suggest about six drained triaxial tests are needed for routine engineering where a precision of ±1.0° may suffice. However, for research or high precision work, more than twenty drained triaxial tests may be needed to determine φc to an accuracy of ±0.5° at 90% confidence. In all cases, tested samples should be uniformly distributed across the range of the soil's relative density.  相似文献   

11.
《Urban Water Journal》2013,10(7):713-721
ABSTRACT

A pervious concrete area (50 m2) was constructed for a dual purpose: stormwater management and bicycle parking. It consisted of two subareas (PCa and PCb) with dissimilar characteristics of pervious concrete mixes in strength, durability and permeability. To make the construction more eco-friendly and economical, coal fly ash was incorporated as a partial cement replacement by 21.4% in the PCa pervious concrete mix. The PCb was constructed with an industry proprietary pervious concrete mix. The subbase water storage can retain 4.1 m3 of the infiltrated stormwater before discharging excess water to a storm drain. The drainage water had an improved water quality in turbidity, organic carbon, phosphorus and fecal coliform concentrations. However, it had high pH and conductivity which might cause a negative impact on the environment. The constructed area has been in active use since its opening, accommodating ~30 bicycles at once on the safe and comfort pervious surface.  相似文献   

12.
The micro-scale wind turbine industry is expanding in the UK with institutional support and UK legislation encouraging the development of numerous companies with a profusion of design options. The application of micro wind turbines in urban environment is encouraged in the UK via a grant scheme which provides a proportion of the initial capital costs. This development is predicated on the assumption that micro wind turbines have the potential to reduce built environment CO2 emissions. Current methods of estimating the wind speed are reported to over predict by approximately 2.0 m/s. The energy yields of a range of typical micro wind turbines (in the 0.4–2.5 kW size range) were estimated here using two wind speed datasets sited within 1 km of each other recorded with a temporal precision of 10 min. The annual energy yield of a 1.5 kW turbine was found to be 277 kWh and 2541 kWh for the two sites analysed indicating the problem with the current method of yield estimation. Between 33 and 55% of the electricity generated would be exported dependant on the dwelling's electrical demand. For the high yield site, the simple economic payback of this turbine was found to be 26.8 years i.e. beyond the likely life time of the turbine with CO2 savings of 1093 kg CO2. The research suggests that this technology does represent a possible route for reducing CO2 emissions but this is unlikely to be realised unless an adequate method is found for more accurately predicting energy yield at a specific site.  相似文献   

13.
Phosphogypsum (PG: CaSO4·2H2O) is a waste product generated by the phosphate industry. World production of this waste exceeds 200 million tonnes per year. PG, discharged into the sea, watercourses or in wilderness stocks, contains toxic elements harmful to ecosystems and human health, including heavy metals and radionuclides, and there is therefore a concern regarding environmental impacts. The concentrations of these elements vary between the regions and the processes used, all of which require particular and specific follow-up after the release of PG and during its use. Phosphogypsum is used in agriculture for soil amendment or as fertilizer, as well as in the brick and cement industry, and in road construction.  相似文献   

14.
Electrochemical advanced oxidation processes are the most promising methods for destroying and degrading organic and inorganic pollutants present in produced water effluents. This study presents the electro-oxidation process using graphite electrodes and electro-Fenton process using iron electrodes for the treatment of real produced water. The effect of operating parameters such as current density on chemical oxygen demand (COD) removal efficiency was addressed. The result showed that electro-Fenton process was more efficient than electro-oxidation process where it gave 98% as maximum COD removal efficiency with energy consumption of 1.9 kWh/dm3 at H2O2 concentration of 12 mM, current density of 10 mA/cm2, temperature of 25°C, pH of 3, and treatment time of 80 min compared with 96.9% as maximum COD removal efficiency with energy consumption of 3 kWh/dm3 at pH of 6, current density of 10 mA/cm2, temperature of 40°C, and reaction time of 80 min when using electro-oxidation process. These results demonstrated that electrochemical technologies are very promising methods for the treatment of produced water from oil/gas industry, so it can be safely disposed of or effectively reused for injection and irrigation.  相似文献   

15.
Since several years odour nuisance is a serious environmental concern in the city of Terni, whose citizens are repeatedly lamenting the presence of malodours. This paper describes the olfactometric approach adopted for assessing the odour impact on the city of Terni, caused by the co-presence of three important industrial poles: the steel industry pole, the chemical pole and a third industrial pole, comprising different activities for the treatment of wastewaters and solid waste. The combination of analyses by dynamic olfactometry and dispersion modelling allowed the evaluation of the citizens' exposure to the industrial odours, resulting in both the quantification of emissions and the assessment of their impact on the territory. The overall odour emissions were estimated to be equal to 218,000 ouE s− 1: 51% from the steel industry pole, 29% from the chemical pole and 20% from the other plants, respectively. The simulation of the emission dispersion shows that the odour impact relevant to all three studied industrial poles is considerable, actually investing almost the whole city of Terni. The study results also enabled the identification of the most problematic odour sources, which turned out to be the primary emissions from the furnace for the steel industry pole, Treofan and the wastewater treatment plant for the chemical pole and the municipal wastewater treatment plant and the pulper incinerator as far as the other plants are concerned.  相似文献   

16.
随着混凝土行业近年来的逐步升温,越来越多的人选择进入混凝土搅拌站行业。一方面.激烈的竞争直接导致企业在管理方面难免出现疏漏;大量的从业人员在技术方面没有良好的职业素养和工作能力,导致混凝土安全问题时有发生;另一方面,企业因为庞大的人员负担无法集中精力发展自己的核心业务,资源也无法得到高效利用。正是在这种背景下,第三方物流应运而生.它让更多的混凝土企业安心投入到混凝土本身的生产中去,从而增强自身的核心竞争力,在市场中博得一席之地。  相似文献   

17.
Struvite is a suitable fertilizer, and electrochemical precipitation of nutrients from industrial waters provides one answer to the circular economy. Molar ratio between ammonium and phosphate is crucial: Water suitable for the precipitation includes more or at least the same amount ammonium than phosphate. That kind of water typically does not exist in industry. Therefore, ammonium-rich industrial water was mixed with phosphorus-rich water to obtain a suitable molar ratio for struvite precipitation. Parameters were studied to determine their effect on removal-% and struvite yield. 100% struvite yield was obtained under several conditions even without pH control with pH 7–9. The highest phosphate removal (99.7%) was occurred with the molar ratio 1.7:2:1 for Mg:NH4:PO4 (pH 9.0). Waters dilution prevents magnesium anode corrosion. Formed struvite has potential as recycled fertilizer due to low bioavailability of metals and high leachability of nutrients studied by four-stage sequential leaching.  相似文献   

18.
刊首语     
《景观设计》2008,(6):1-1
十月初闻冬的脚步《景观设计》与您共同回顾携手走过的这极不平凡的年:2008年发生的诸多自然灾害促使景观设计行业重新审视人与自然和谐共生的关系以厦景观设计师在二者之间应扮演的角色.房地产行业的低迷也间接影响着景观设计行业前行的脚步。中国景观设计行业面对着前所未有的竞争和挑战——在曲折中前行在探索中试水。《景现设计》杂志也力求通过不懈努力发掘更多具有借鉴意义的项目带给业内人士些新的启发和触动.  相似文献   

19.
In an attempt to convert waste product into useful material for the construction industry, this research considered the use of corn cob ash (CCA) as a pozzolan in cement production. The study investigated the chemical composition of CCA. Factory production of the CCA – blended cement was carried out by replacing 0%, 2%, 4%, 6%, 8%, 10%, 15%, 20% and 25% by weight of Ordinary Portland Cement clinker with CCA. The 0% replacement serves as the control. The results showed that CCA is a suitable material for use as a pozzolan as it satisfied the minimum requirement of combined SiO2 and Al2O3 of more than 70%, which a good pozzolan for manufacture of blended cement should meet. The blended cements produced also satisfied both NIS 439:2000 and ASTM C 150 requirements especially at lower levels (<15%) of CCA percentage replacement. Based on the test results, it was concluded that CCA could be suitably used in blended cement production.  相似文献   

20.
Through the position it holds in the nation's economy, the Egyptian construction industry has an important effect on the country's social and economic growth and development. In the past, the industry's problems stemmed from a lack of resources and technological expertise, but more recently it is the management and administration of those problems that have assumed greater prominence. The paper describes briefly the formal construction industry in Egypt and highlights the factors that currently constrain its effective operation. A call is made for better management and greater stability so that both the capacity and the efficiency of the industry can be improved.  相似文献   

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