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Atmospheric Dispersion Modeling of the Emissions from the Logbaba Thermal Power Plant, Douala-Cameroon  [PDF]
R. Mbiaké, E. Mfoumou, A. Beya Wakata, E. Ndjeuna, J. R. Kaze Djamen, R. Leduc, C. Bobda
Open Journal of Air Pollution (OJAP) , 2017, DOI: 10.4236/ojap.2017.64010
Abstract: Air quality in the vicinity of the thermal power plant of Logbaba in the town of Douala was investigated in this study using data collected in a 5-year period (2008-2012). The distribution of pollutants such as SO2, NOx, CO and the particle matter PM2.5 was analyzed using numerical modeling, based on physical and thermal characteristics, as well as the operating periods of the power plant. The American Environmental Regulator Model (AERMOD) that is an atmospheric dispersion model was used for simulation. The wind rose and others National Oceanic Atmospheric Administration (NOAA) in-situ data were used for the validation of the model. The pollutants distribution was evaluated at two locations: the exit of the power plant, considered as reference point, and at 330 m away from the exit where the first houses appeared. The results show that the relative concentration for each contaminant at the exit of the power plant is 7.2% for the PM2.5 during 24 hours of emission, 46.0% for CO over 8 hours of emission, and 17.5% for SO2 over one hour. The NOx is the highest pollutant with 259.1% over an hour of emission and 51.0% over one year. Beyond 330 m of the power plant, only NOx keeps a polluting character with a relative rate of 100%. These results show that the pollution level of the power plant is over the threshold for air quality set by the World Health Organization. Moreover, among all pollutants investigated, NOx appears to be the most critical for the population in the vicinity of the Logbaba thermal power plant. This information is therefore important for policy and decision makers in preventing the vulnerability of the population to air pollutants from such industrial settings.
Improvement of environmental aspects of thermal power plant operation by advanced control concepts  [PDF]
Mikulandri? Robert,Lon?ar Dra?en,Cvetinovi? Dejan,Spiridon Gabriel
Thermal Science , 2012, DOI: 10.2298/tsci120510134m
Abstract: The necessity of the reduction of greenhouse gas emissions, as formulated in the Kyoto Protocol, imposes the need for improving environmental aspects of existing thermal power plants operation. Improvements can be reached either by efficiency increment or by implementation of emission reduction measures. Investments in refurbishment of existing plant components or in plant upgrading by flue gas desulphurization, by primary and secondary measures of nitrogen oxides reduction, or by biomass co-firing, are usually accompanied by modernisation of thermal power plant instrumentation and control system including sensors, equipment diagnostics and advanced controls. Impact of advanced control solutions implementation depends on technical characteristics and status of existing instrumentation and control systems as well as on design characteristics and actual conditions of installed plant components. Evaluation of adequacy of implementation of advanced control concepts is especially important in Western Balkan region where thermal power plants portfolio is rather diversified in terms of size, type and commissioning year and where generally poor maintenance and lack of investments in power generation sector resulted in high greenhouse gases emissions and low efficiency of plants in operation. This paper is intended to present possibilities of implementation of advanced control concepts, and particularly those based on artificial intelligence, in selected thermal power plants in order to increase plant efficiency and to lower pollutants emissions and to comply with environmental quality standards prescribed in large combustion plant directive. [Acknowledgements. This paper has been created within WBalkICT - Supporting Common RTD actions in WBCs for developing Low Cost and Low Risk ICT based solutions for TPPs Energy Efficiency increasing, SEE-ERA.NET plus project in cooperation among partners from IPA SA - Romania, University of Zagreb - Croatia and Vinca Institute from Serbia and. The project has initiated a strong scientific cooperation, with innovative approaches, high scientific level, in order to correlate in an optimal form, using ICT last generation solutions, the procedures and techniques from fossil fuels burning processes thermodynamics, mathematical modelling, modern methods of flue gases analysis, combustion control, Artificial Intelligence Systems with focus on Expert Systems category.]
Changes in the distribution of South Korean forest vegetation simulated using thermal gradient indices
Sungho Choi,Woo-Kyun Lee,Yowhan Son,Seongjin Yoo,Jong-Hwan Lim
Science China Life Sciences , 2010, DOI: 10.1007/s11427-010-4025-1
Abstract: To predict changes in South Korean vegetation distribution, the Warmth Index (WI) and the Minimum Temperature of the Coldest Month Index (MTCI) were used. Historical climate data of the past 30 years, from 1971 to 2000, was obtained from the Korea Meteorological Administration. The Fifth-Generation National Center for Atmospheric Research (NCAR) /Penn State Mesoscale Model (MM5) was used as a source for future climatic data under the A1B scenario from the Special Report on Emission Scenario (SRES) of the Intergovernmental Panel on Climate Change (IPCC). To simulate future vegetation distribution due to climate change, the optimal habitat ranges of Korean tree species were delimited by the thermal gradient indices, such as WI and MTCI. To categorize the Thermal Analogy Groups (TAGs) for the tree species, the WI and MTCI were orthogonally plotted on a two-dimensional grid map. The TAGs were then designated by the analogue composition of tree species belonging to the optimal WI and MTCI ranges. As a result of the clustering process, 22 TAGs were generated to explain the forest vegetation distribution in Korea. The primary change in distribution for these TAGs will likely be in the shrinkage of areas for the TAGs related to Pinus densiflora and P. koraiensis, and in the expansion of the other TAG areas, mainly occupied by evergreen broad-leaved trees, such as Camellia japonica, Cyclobalanopsis glauca, and Schima superba. Using the TAGs to explain the effects of climate change on vegetation distribution on a more regional scale resulted in greater detail than previously used global or continental scale vegetation models.
Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder
C. Clerbaux, A. Boynard, L. Clarisse, M. George, J. Hadji-Lazaro, H. Herbin, D. Hurtmans, M. Pommier, A. Razavi, S. Turquety, C. Wespes,P.-F. Coheur
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2009,
Abstract: Atmospheric remote sounding from satellites is an essential component of the observational strategy deployed to monitor atmospheric pollution and changing composition. The IASI nadir looking thermal infrared sounder onboard MetOp will provide 15 years of global scale observations for a series of key atmospheric species, with unprecedented spatial sampling and coverage. This paper gives an overview of the instrument's capability for measuring atmospheric composition in the perspective of chemistry and air quality. The assessment is made in terms of species, accuracy and vertical information. Global distributions are presented for CO, CH4, O3 (total and tropospheric), HNO3, NH3, and volcanic SO2. Local distributions of organic species measured during fire events, such as C2H4, CH3OH, HCOOH, and PAN are also shown. For each species or process, the link is made to specialized papers in this issue.
Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder  [PDF]
C. Clerbaux,A. Boynard,L. Clarisse,M. George
Atmospheric Chemistry and Physics Discussions , 2009,
Abstract: Atmospheric remote sensing from satellite is an essential component of the observational strategy deployed to monitor atmospheric pollution and changing composition. The IASI nadir looking thermal infrared sounder onboard MetOp will provide 15 years of global scale observations for a series of key atmospheric species, with unprecedented spatial sampling and coverage. This paper gives an overview of the instrument's capability for measuring atmospheric composition in the perspective of chemistry and air quality studies. The assessment is made in terms of species, accuracy and vertical information. Global distributions are presented for CO, CH4, O3 (total and tropospheric), HNO3, NH3 and volcanic SO2. Local distributions of organic species measured during fire events, such as C2H4, CH3OH, HCOOH, and PAN are also shown. For each species or process, the link is made to specialized papers in this issue.
Investigations of plant infections by thermal vision and NIR imaging
H.J. Hellebrand,W.B. Herppich,H. Beuche,K.-H. Dammer
International Agrophysics , 2006,
Abstract: The successful applicability of thermal vision in horticulture was the starting point to launch a project in plant protection. Earlier studies proved the applicability of thermal vision for the assessment of freshness status and of microbial infestation by local temperature differences of plant parts. In recent laboratory experiments, studies were performed on the development of infestation of wheat plants which were infected by powdery mildew and by stripe rust. Fungi infections, which may cause variations of the surface temperature of plants, could be recognised by infrared cameras in the thermal range under laboratory conditions. Field studies revealed that pronounced natural temperature variations of several Kelvin within the crop canopy prevented the recognition of infected plants. Additionally, the comparatively low resolution of commercial thermal vision systems limited the detection chances of fungi-caused temperature variations within the plant canopy. Near infrared cameras fitted with band-pass filters showed different intensity distributions of the reflected radiation. The evaluation of the spectral intensity relations improved the differentiation.
ASSESSMENT OF THE DRUM REMAINING LIFETIME IN THERMAL POWER PLANT  [cached]
Miroslav M ?ivkovi?,Sne?ana D Vulovi?,Rodoljub S Vujanac
Thermal Science , 2010, DOI: tsci100507030z
Abstract: In this paper analysis of stress and thermal-elastic-plastic strain of the drum is performed. Influence of modified thickness, yield stress and finite element model of welded joint between pipe and drum on assessment of the remaining lifetime of the drum in the thermal power plant is analyzed. Two analyses are compared. In the first, drum is modeled by shell and by 3D finite elements with projected geometrical and material data of drum. Then, the drum is modeled by shell and by 3D finite elements with modified thickness and yield stress. The analysis show that detailed modeling of stress concentration zones is necessary. Adequate modeling gives lower maximal effective plastic strain and increased number of cycles and, in that case, 3D finite elements are better comparing to shell finite elements.
生活垃圾焚烧发电厂烟塔合一大气环境影响分析
Analysis of Atmospheric Environmental Impact for Municipal Solid Waste Incineration Plant Using Natural Draft Cooling Towers with Flue Gas Injection
 [PDF]

胡耘, 王圣, 赵秀勇
Advances in Environmental Protection (AEP) , 2015, DOI: 10.12677/AEP.2015.56021
Abstract:
本文针对安徽某生活垃圾焚烧发电厂,模拟烟塔合一和烟囱排放两种不同排烟方式对大气环境的影响并进行比较,结果表明烟塔方案较烟囱方案的小时浓度、日均浓度较高,但年均浓度明显较低。同时,通过环境风洞实验确定了采用烟塔合一排烟方式时的环境防护距离,未超过“环发[2008]82号”要求“新改扩建项目环境防护距离不得小于300 m”,不会因采取烟塔合一方案而增加额外的拆迁需求。研究结果对生活垃圾焚烧发电厂排烟方式的优化选择具有一定参考价值。
As the case study of a municipal solid waste (MSW) incineration plant in Anhui Province, the maxi- mum ground concentration from natural draft cooling towers (NDCT) with flue gas injection of 88 m high is calculated in this paper, as a parallel calculation, the maximum ground concentrations from a 60 m high chimney and an 80 m high chimney are calculated. The results show that, compared with the concentrations from the chimneys, the maximum yearly average ground concentration from a 88 m high cooling tower is lower, but the maximum daily and hour average ground concentrations are higher. Also, this paper determines the atmospheric environmental protection zone for NDCT with flue gas injection by physical simulation experiment in environmental wind tunnel. The determined zone is within the area required by MEP (Ministry of Environmental Protection of the People’s Republic of China), so there is no more demand for relocation causing by NDCT with flue gas injection. This research is valuable for the optimal selection of flue gas exhausting methods in municipal solid waste incineration plant.
Laser Spectroscopy for Atmospheric and Environmental Sensing  [PDF]
Marc N. Fiddler,Israel Begashaw,Matthew A. Mickens,Michael S. Collingwood,Zerihun Assefa,Solomon Bililign
Sensors , 2009, DOI: 10.3390/s91210447
Abstract: Lasers and laser spectroscopic techniques have been extensively used in several applications since their advent, and the subject has been reviewed extensively in the last several decades. This review is focused on three areas of laser spectroscopic applications in atmospheric and environmental sensing; namely laser-induced fluorescence (LIF), cavity ring-down spectroscopy (CRDS), and photoluminescence (PL) techniques used in the detection of solids, liquids, aerosols, trace gases, and volatile organic compounds (VOCs).
Which Environmental Factors Caused Lammas Shoot Growth of Korean Red Pine?
Lee, Chang-Seok,Hye-Gyung Song,Hye-Soo Kim,Bitnara Lee
Journal of Ecology and Field Biology , 2007,
Abstract: Lammas growth, a rare phenomenon for Korean red pine (Pinus densiflora), occurred in 2006.Lammas shoots showed higher frequency and longer length in Seoul's hotter urban center than in urbanboundary or suburban forest sites. Frequency and length showed a close correlation with urbanization densityand vegetation cover expressed in NDVI. Air temperature in the late summer of 2006 was more than 1℃ higherthan an average year. Of the predominant environmental signals that modulate bud flush, only temperaturechanged significantly during the year. Differences in temperature between the urban centers, urban boundariesand suburban forests correlated with varying land-use density. The rise in temperature likely spurred lammasgrowth of the Korean red pine. Symptoms of climate change are being detected throughout the world, and itsconsequences will be clearer in the future. Considerate interest in the responses of ecological systems to thevariable changes is required to prepare for unforeseeable crises. Monitoring of diverse ecological phenomenaat Long Term Ecological Research sites could offer harbingers of change.
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