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171.
Pressure-retarded osmosis (PRO) is a method for converting salinity gradients to power by allowing water to flow through a semi-permeable membrane against an applied hydraulic pressure. PRO already has a long history, starting from the middle of the last century, and has rapidly improved in recent years. In this paper, we present a historical development of PRO since its inception: the development of this renewable energy process has gone through several stages, depending on technological developments, worldwide energy demands, and environmental concerns. The technological progress of the process is also studied, as well as its cost viability and environmental impact. Finally, some ideas to further develop the PRO process and mitigate its detrimental effects are discussed. 相似文献
172.
Majority of the studies on offshore wind power potential assessment is limited to the examination of the wind speed only. This study examines the offshore wind power potential of the Black Sea coastal region in Turkey based on location selection criteria including territorial waters, military areas, civil aviation, shipping routes, pipelines and underground cables, social, and environmental concerns. Wind Atlas Analysis and Application Program (WAsP) is used to do the statistical analysis of wind speed and wind direction data for 20 locations in the Black Sea coastal region. WAsP results are then elaborated based on the location selection criteria for better assessment of offshore wind power utilization. The study reveals that there are limited numbers of locations for offshore wind power generation in the Black Sea region in spite of its long coastline. Moreover, there is a high need for a zoning change for Amasra shores in order to utilize high offshore wind power potential of Amasra. Our finding suggests that location selection criteria other than wind speed should definitely be considered for better assessment of the wind power potential of a region. 相似文献
173.
Fate of pharmaceuticals and personal care products in wastewater treatment plants - Conception of a database and first results 总被引:1,自引:0,他引:1
C. Miège J.M. Choubert L. Ribeiro M. Eusèbe M. Coquery 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1721-1726
We created a database in order to quantitatively assess the occurrence and removal efficiency of pharmaceuticals and personal care products (PPCPs) in wastewater treatment plants (WWTPs). From 117 scientific publications, we compiled 6641 data covering 184 PPCPs. Data included the concentrations of PPCPs in WWTP influents and effluents, their removal efficiency and their loads to the aquatic environment. The first outputs of our database allowed to identify the most investigated PPCPs in WWTPs and the most persistent ones, and to obtain reliable and quantitative values on their concentrations, frequency of detection and removal efficiency in WWTPs. We were also able to compare various processes and pointed out activated sludge with nitrogen treatment and membrane bioreactor as the most efficient ones. 相似文献
174.
An Assessment of Stakeholder Perceptions and Management of Noxious Alien Plants in Spain 总被引:1,自引:1,他引:0
Despite biological invasions being a worldwide phenomenon causing significant ecological, economic, and human welfare impacts,
there is limited understanding regarding how environmental managers perceive the problem and subsequently manage alien species.
Spanish environmental managers were surveyed using questionnaires to (1) analyze the extent to which they perceive plant invasions
as a problem; (2) identify the status, occurrence, and impacts of noxious alien plant species; (3) assess current effort and
expenditure targeting alien plant management; and, finally, (4) identify the criteria they use to set priorities for management.
In comparison to other environmental concerns, plant invasions are perceived as only moderately problematic and mechanical
control is the most valued and frequently used strategy to cope with plant invasions in Spain. Based on 70 questionnaires
received, 193 species are considered noxious, 109 of which have been the subject of management activities. More than 90% of
species are found in at least one protected area. According to respondents, the most frequently managed species are the most
widespread across administrative regions and the ones perceived as causing the highest impacts. The perception of impact seems
to be independent of their invasion status, since only half of the species identified as noxious are believed to be invasive
in Spain, while 43% of species thought to only be casual aliens are causing a high impact. Records of management costs are
poor and the few data indicate that the total actual expenditure amounted to 50,492,437 € in the last decade. The majority
of respondents stated that management measures are insufficient to control alien plants due to limited economic resources,
lack of public awareness and support, and an absence of coordination among different public administrations. Managers also
expressed their concern about the fact that much scientific research is concerned with the ecology of alien plants rather
than with specific cost-efficient strategies to manage alien species. 相似文献
175.
Arun Kansal Mukesh Khare Chandra Shekhar Sharma 《Journal of Environmental Planning and Management》2009,52(7):881-899
This study estimates minimum marginal health benefits (morbidity reduction only) of air pollution control and total health benefits arising from regulatory intervention regarding the adoption of the World Bank emission guidelines (WBEG) for thermal power plants (TPPs) in Delhi. The Industrial Source Complex-Short-Term Version–3 (ISCST3) model has been used to estimate the contribution to air pollution from TPPs. The household health production function (avertive behaviour) has been used to value health benefits of air pollution control. The study revealed that the ambient air pollution due to TPPs is reduced by between 62.17% to 83.45% by adopting the WBEG. Annual marginal benefit due to reduction in exposure to air pollution by 1 μg m?3 is estimated to be US$0.353 per person. Total annual health benefits for adopting the WBEG for TPPs are estimated at US$235.19 million. This study provides a novel methodology to evaluate health benefits of regulatory intervention. 相似文献
177.
178.
Rita Castro Sofia Pereira Ana Lima Sofia Corticeiro Mnica Vlega Eduarda Pereira Armando Duarte Etelvina Figueira 《Chemosphere》2009,76(10):1348-1355
This work evaluates the role of a plant community in mercury (Hg) stabilization and mobility in a contaminated Portuguese salt marsh. With this aim, the distribution of Hg in below and aboveground tissues, as well as the metal partitioning between cellular fractions (soluble and insoluble) in four different species (Triglochin maritima L., Juncus maritimus Lam, Sarcocornia perennis (Miller) A.J. Scott, and Halimione portulacoides (L.) Aellen) was assessed. Mercury accumulation, translocation and compartmentation between organs and cellular fractions were related to the plant species.Results showed that the degree of Hg absorption and retention was influenced both by environmental parameters and metal translocation/partitioning strategies. Different plant species presented different allocation patterns, with marked differences between monocots (T. maritima and J. maritimus) and dicots (S. perennis, H. portulacoides). Overall, the two monocots, in particular T. maritima showed higher Hg retention in the belowground organs whereas the dicots, particularly S. perennis presented a more pronounced translocation to the aboveground tissues. Considering cellular Hg partitioning, all species showed a higher Hg binding to cell walls and membranes rather than in the soluble fractions. This strategy can be related to the high degree of tolerance observed in the studied species. These results indicate that the composition of salt marsh plant communities can be very important in dictating the Hg mobility within the marsh ecosystem and in the rest of the aquatic system as well as providing important insights to future phytoremediation approaches in Hg contaminated salt marshes. 相似文献
179.
我国火电厂脱硫脱硝行业2008年发展综述 总被引:1,自引:0,他引:1
中国环境保护产业协会锅炉炉窑脱硫除尘委员会 《中国环保产业》2009,(7):8-13,19
介绍了2008年我国火电厂脱硫脱硝行业的发展概况,分析了行业存在的主要问题,并提出了对策及建议。 相似文献
180.
以位于自然保护区边缘的火电厂建设项目环境影响评价为实例,阐述了火电厂生态环境评价中对自然保护区珍稀鸟类的保护方法,以供类似项目的生态环境影响评价借鉴。 相似文献