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991.
Evaluation of mercury speciation and removal through air pollution control
devices of a 190 MW boiler 总被引:1,自引:0,他引:1
Chengli Wu Yan Cao Zhongbing Dong Chinmin Cheng Hanxu Li Weiping Pan 《环境科学学报(英文版)》2010,22(2):277-282
Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction
(SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration
and operational conditions of APCDs and mercury speciation a ect mercury removal e ciently at coal-fired utilities. The Ontario
Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation
simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor
a ecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more
elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized
mercury when SCR was in service, and oxidation e ciency reached 71.0%. Therefore, oxidized mercury removal e ciency was
enhanced through a wet FGD system. In the non-ozone season, about 89.5%–96.8% of oxidized mercury was controlled, but only
54.9%–68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal e ciency was 95.9%–98.0%, and there
was a big di erence in the total mercury removal e ciencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was
evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from
0.84 to 1.08. 相似文献
992.
Using a revised version of a previously published expert classification system, a database of potential Sustainable Flood Retention Basins has been developed for Scotland. The research shows that the majority of small and former (often old) drinking water reservoirs are kept full and their spillways are continuously in operation. Utilising some of the available capacity to contribute to flood control could significantly reduce the costs of complying with the European Union Flood Directive. Furthermore, the application of a previously developed classification model for Baden in Germany for the Scottish data set showed a lower diversity for basins in Scotland due to less developed infrastructure. The classification system appears to be robust and has the potential, with minor modifications, to be applied across Europe. The principle value of this approach is a clear and unambiguous categorisation, based on standard variables, which can help to promote communication and understanding between stakeholders. 相似文献
993.
994.
Prodigiosin is a reddish antibiotic pigment that plays an important role in the biocontrol of plant diseases by the bacterium
Serratia marcescens. However, its activity is unstable under agricultural conditions; further, it can be degraded by various environmental factors.
To examine the effect of epiphytic microbes on the stability of prodigiosin used for biological control processes, we collected
a total of 1,280 bacterial isolates from the phylloplane of cyclamen and tomato plants. Approximately 72% of the bacterial
strains isolated from the cyclamen plants and 66% of those isolated from the tomato plants grew on minimal agar medium containing
100 μg ml−1 prodigiosin. Certain isolates obtained from both plant species exhibited prodigiosin-degrading activity. We compared the
16S rRNA gene sequences derived from the isolates with sequences in a database. The comparison revealed that the sequences
determined for the prodigiosin-degrading isolates were homologous to those of the genera Pseudomonas, Caulobacter, Rhizobium, Sphingomonas, Janthinobacterium, Novosphingobium, and Rathayibacter. These results indicate that indigenous epiphytic microorganisms may interfere with the interaction between plant pathogens
and biocontrol agents by degrading the antibiotics produced by the agents. 相似文献
995.
对在粪大肠菌群实验过程中涉及到的实验室质控设备、培养基、精密度检验等内容进行了分析,并对实验过程中的关键问题进行了阐述。 相似文献
996.
N. Anger B. Brouns J. Onigkeit 《Mitigation and Adaptation Strategies for Global Change》2009,14(5):379-398
We investigate the role of domestic allowance allocation and global emissions constraints for the carbon-market impacts of
linking the EU Emissions Trading Scheme (ETS) internationally. Employing a quantitative simulation model of the global carbon
market, we find that the economic benefits from connecting the European ETS to emerging non-EU schemes strongly depend on
the regional allowance allocation of the linking participants: In a world of moderate carbon constraints, an economically
efficient regional allowance allocation induces a much stronger fall in total compliance costs than a sub-optimal (i.e. too
high) domestic allocation of emissions permits. However, a more efficient (i.e. stricter) allocation shifts abatement efforts
and compliance costs to energy-intensive industries which are covered by the domestic ETS. We further find that committing
to ambitious global emissions reduction targets (compatible with stabilizing CO2 concentrations at 450 ppm) induces much stronger regional abatement efforts and substantially higher compliance costs for
the abating regions. In such an ambitious climate policy regime, an efficient domestic allocation of allowances is even more
important from an economic perspective: Here, linking emissions trading schemes diminishes the associated compliance costs
on the largest scale.
相似文献
J. OnigkeitEmail: |
997.
C. Streck A. Tuerk B. Schlamadinger 《Mitigation and Adaptation Strategies for Global Change》2009,14(5):455-463
An important aspect in the linking of different emissions trading schemes is the degree to which these systems allow (or ban)
external offset project categories. The EU Emission Trading Scheme (EU ETS) currently allows the use of credits from energy
and industry projects developed under the Kyoto Protocol’s Joint Implementation (JI) and Clean Development Mechanism (CDM)
but excludes the use of carbon credits from forestry projects for compliance in the EU ETS. Forestry credits generated by
the CDM have a limited lifetime and expire at the end of a project’s crediting period, or earlier if the carbon stock for
which the credits have been issued ceases to exist. According to the recently adopted amendment of the EU ETS Directive forestry
credits will remain to be excluded until 2020. The present article reviews how the New South Wales Greenhouse Gas Abatement
Scheme (Australia), the Regional Greenhouse Gas Initiative (US) and the voluntary scheme of the Chicago Climate Exchange integrate
forestry offsets into the respective system and how they deal with the risk of losing stored and credited biomass. By comparing
the results of different scenarios this article shows how differences in the treatment of forestry offsets could impact the
efforts to link various emission trading systems in future.
相似文献
A. TuerkEmail: |
998.
We address the future of science and governance for the California Delta, focusing on the CALFED Bay-Delta Program, an interagency, multi-stakeholder effort to understand and manage the Delta for multiple purposes. We portray a Delta history as a coevolutionary process between science, governance and ecosystems. Global integrated environmental assessments (IEA) provide insights into understanding complex, dynamic socio-ecological systems. Many of the discursive stakeholder and scientific activities that have arisen under CALFED are similar to IEA and remain essential to the shared learning needed to effectively interact with a dynamic Delta. More deliberately enmeshing environmental monitoring, analysis, and collective learning into Delta governance will improve outcomes. 相似文献
999.
同一工业行业内的企业存在排污强度个体差异,从数量有限的企业环境统计数据得出行业平均排污强度,并用其代表该行业在区域层面的经济-环境水平,会带来一定偏差.因此以嵌入环境消耗投入的生产函数为基础,建立了企业运营决策的微观模拟模型,从机制上描述企业排污强度的差异.以2005年德阳市机械制造行业为案例,对模型的相关参数进行了率定,使其较好地描述了2005年环境统计口径内各企业的COD排放强度.模型的计算结果表明,由环境统计口径内企业计算的区域平均COD排放强度(万元固定资产排放0.002 6 t,万元工业产值排放0.001 5 t)小于由区域内全部企业计算的区域平均COD排放强度(万元固定资产排放0.003 0 t,万元工业产值排放0.002 3 t),市域内6个县级行政区的排污强度也体现出了明显差异.以上的排污强度区域特征主要源自行业内部结构(企业的规模分布,技术分布),及其空间差异. 相似文献
1000.
雨水管道沉积物对径流初期冲刷的影响 总被引:7,自引:0,他引:7
为了避免汇水面源头以及分流制雨水管道系统中沉积的大量污染物在降雨时随雨水径流被冲刷进入水体,从而控制径流对水环境构成的冲击性污染,从理论和试验2方面分析了管道径流污染物(汇水面和管道沉积物2个来源)的流失规律.结果表明,汇水面源头污染物流失较符合源头冲刷的指数衰减模型,管道内沉积物流失可用流量曲线模型计算;管道内沉积物占管道径流污染物的比例越大,管道径流的初期冲刷现象越不明显.为了提高径流污染控制设施的效率,宜在源头进行分散控制,并加强雨水管网系统清洁维护,避免污染物的积累. 相似文献