Dissertations / Theses on the topic 'Thermal power plants - Air pollution'

In this study, emission inventory was prepared and pollutant dispersion studies were carried out for the area around Ç
ayirhan Thermal Power Plant to determine the effects of the plant on the environment. Stack gas measurement results were used for the emissions from the power plant and emission factors were used for calculating the emissions from residential sources and coal stockpiles in the study region. Ground level concentrations of SO2, NOx and PM10 were estimated by using EPA approved dispersion models
namely ISCST3 and AERMOD. The ground level concentrations predicted by two models were compared with the results of ambient air pollution measurements for November 2004. Predictions of both ISCST3 and AERMOD were underestimating the ground level SO2 concentrations. However, AERMOD predictions are better than ISCST3 predictions. The results of both models had good correlation with the results of NOx measurements. It has been shown that the contribution of the power plant to SO2, NOx and PM10 pollution in the area studied is minimal.

Le droit applicable aux centrales thermiques implique de nombreux enjeux environnementaux. Si la pollution atmosphérique et le changement climatique sont les plus cités, la pollution de l’eau fait également partie de ceux-ci. La protection de l’environnement, que ce soit en droit français ou en droit chinois, se réalise de différentes façons en fonction de l’étape de la vie de la centrale mais aussi du milieu qui cherche à être protégé. Si les similitudes entre le droit français et le droit chinois sont nombreuses, des différences existent également.Dans le cas de la construction future de ces centrales, de manière générale, ou d’un projet précis d’une centrale, la façon de protéger l’environnement a connu d’importants changements ces dernières années. Si le niveau de protection est aujourd’hui encore largement local, il tend à devenir de plus en plus global en prenant en compte un nombre croissant d’éléments durant la phase de réflexion du projet. Dans le cas des émissions quotidiennes dans l’air et dans l’eau des centrales thermiques en fonctionnement, un certain niveau de protection de l’environnement est assuré en les limitant. La limitation passe principalement par la fixation de seuils qui forment le socle fondamental de cette protection quotidienne et sont complétés par d’autres outils juridiques. Enfin, cette protection de l’environnement passe par la vigilance par le biais du système de la surveillance des émissions mais aussi par l’anticipation liée à l’éventuel dysfonctionnement de la centrale et la période post-fonctionnement de celle-ci
Applicable law to thermal power plants involves many environmental issues. If air pollution and climate change are the most well-known issues, water pollution is also one of them. Environmental protection, whether in French or Chinese law, is achieved in different ways depending on the stage of the plant’s life but also on the environment that seeks to be protected. If they are many similarities between French law and Chinese law, many differences also exist.In the case of the future construction of these plants in general, or of a specific plant project, the way of protecting the environment has undergone significant changes in recent years. If the level of protection is still largely local nowadays, it tends to become more and more global by taking increasing amount of elements when the power plant project is carried out. In the case of daily air and water emissions from thermal power plants in operation, some environmental protection is ensured by limiting them. The limitation mainly involves the setting of emission limits which try to be gradually lowered. These form the fundamental foundation of this daily protection and are complemented by other legal tools. Finally, this protection of the environment requires vigilance through the emissions monitoring system but also through anticipation linked to the possible malfunction of the power plant and the post-operation period of it

Thesis (MScEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Concentrating solar power technology is a modern power generation technology in which central receiver systems play a significant role. For this technology a field of heliostats is used to reflect solar irradiation to the receiver located on top of the tower. An extensive review has shown that contemporary receiver designs face geometric complexities, lack of thermal efficiency as well as issues with durability and cost. The purpose of this study is to develop a new receiver concept that can potentially reduce these issues. A parametric analysis was used to identify potential means of improvement based on an energy balance approach including sensitivities involved with convection and radiation heat transfer. Design criteria such as the use of headers to minimize pressure drop was also investigated. Based on these findings the hybrid pressurized air receiver was developed which is a combination of tubular and volumetric receiver technologies. The fundamental idea of the receiver was investigated by simulating the ray-tracing and coupled natural convection and radiation heat transfer. The ray-tracing results have shown that the use of quartz glass is a prospective solution to higher allowable flux densities, but with reflection losses in the order of 7 %. The coupled natural convection heat transfer simulation further revealed that the receiver concept effectively eliminates the escape of buoyant plumes and radiative heat losses are minimized. Empirical data was gathered from a medium flux concentrator and good agreement with the numerical results was obtained. The thesis therefore concludes that the research outcomes were met. Ongoing research aims to optimise the receiver concept for a 5MW pilot plant.
AFRIKAANSE OPSOMMING: Gekonsentreerde sonkrag tegnologie is ’n moderne kragopwekkingstegnologie waar sentrale ontvangersisteme ’n beduidende rol speel. Vir hierdie tegnologie word ’n veld heliostate gebruik om sonstraling na die ontvanger wat aan die bopunt van die toring geleë is te reflekteer. ’n Omvattende hersiening het daarop gewys dat kontemporêre ontwerpe van die ontvangers ’n aantal geometriese kompleksiteite, ’n tekort aan termiese doeltreffendheid sowel as probleme in terme van duursaamheid en koste in die gesig staar. Die doel van die studie is om ’n nuwe ontvangerskonsep te ontwikkel wat moontlik hierdie probleme kan verminder. ’n Parametriese analise is gebruik om potensiële maniere van verbetering aan te dui wat gebaseer is op ’n energiebalans benadering; insluitend sensitiwiteite betrokke by konvektiewe en stralingswarmteoordrag. Ontwerpkriteria soos die gebruik van spruitstukke om drukverliese te minimaliseer is ook ondersoek. Gebaseer op hierdie bevindinge is die hibriede saamgepersde-lug ontvanger ontwikkel. Laasgenoemde is ’n kombinasie van buis- en volumetriese ontvangertegnologie. Die fundamentele idee van die ontvanger is ondersoek deur straalberekening asook die gelyktydige natuurlike konveksie en stralingswarmteoordrag te simuleer. Die straalberekeningsresultate het getoon dat die gebruik van kwarts glas ’n moontlike oplossing is om hoër stralingsintensiteit te bereik, maar met refleksieverliese in die orde van 7 %. Die gelyktydige natuurlike konveksie en stralingswarmteoordrag simulasie het verder aan die lig gebring dat die ontvangerkonsep die ontsnapping

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 81-82).
Air cooled power plants experience significant performance fluctuations as plant cooling capacity reduces due to higher daytime temperature than nighttime temperature. The purpose of this thesis is to simulate the detailed operation of a cold side thermal energy storage system in order to evaluate its potential. An organic Rankine cycle geothermal power station is used as an example application. Detailed sizing and operation considerations are discussed. Several representative case studies compare the performance of candidate configurations. Operation of the selected configuration is then simulated for a full year and a proposed integration of the system with existing plant hardware is laid out. A correlation between weather trends and production is outlined. Finally an economic cost/benefit analysis performed to determine the payback period for implementing the proposed system. The cold side TES system is shown to shift substantial power generation capability from nighttime to daytime when electrical demand is highest, especially during hot summer months. For example, daily energy production is shown to increase by up to 18% under particularly favorable conditions. This redistribution of the power generation curve is accomplished with less than a 5% reduction in overall annual energy production in Mega-Watt hours. The system is shown to be more effective at shifting power generation capacity during warmer months than cooler months. The reduced day to night temperature fluctuation during cooler months results in a reduced thermal storage benefit under similar parasitic loads. The economic benefits of this system are dependent upon the on-peak vs off-peak electricity prices. Economic analysis using 2011 transient price data from the U.S. Midwest Region results in a small increase in annual income. The increased income from the proposed cold side TES system is found to be insufficient to outweigh the required capital investment at current electricity prices.
by Daniel David Williams.
S.M.

The continuous escalation of intermittent energy added to the grid and forecasts of peaking power demand increments are rising the effort spent for evaluating the economic feasibility of energy storages. The aim of this research is the techno-economic analysis of Compressed Air Energy Storage (CAES) systems, capable of storing large quantities of off-peak electric energy in the form of high-pressure air, as an ―energy stock‖ which allows the production of high-profit on-peak electricity when required by the grid. Several studies of both conventional and innovative adiabatic concepts are carried out in order to identify and improve the parameters that mostly affect the plant performances. Technical models, that consider the effect of time, are developed to evaluate the parameters that reduce the electric energy spent for compressing the air and that maximize the electric energy produced. In the conventional plant, particular attention is put on the understanding of the effects of air storage pressure range, recuperator, reheating and Turbine Inlet Temperature. For the adiabatic instead, a thorough analysis of the challenging Thermal Energy Storage (TES) is performed for understanding the advantages and drawbacks of this novel efficient concept of CAES. In a further step the economic analyses are aimed at evaluating the different configurations proposed in the technical investigation and the effects that variations of generation train and storage characteristics have on the profitability. After an analysis of the TES impact on the profits, a final comparison is carried out against two existing technologies: Pumped Hydro Energy Storage and gas turbine. The results of these studies confirm, from a technical and economic point of view, the reasons of the growing interest toward CAES as a feasible solution to manage the intermittent energy production. In particular they underline the conventional CAES as promising technology to undertake.

Thesis (PhD)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: During the last 30 years I have been involved in the theory and practice of thermal engineering and in particular, in the areas of air-cooled heat exchangers and cooling towers for the power, refrigeration, process and petrochemical industries in South Africa and internationally. During this period, I have authored and co-authored more than 120 papers that were published in technical journals or presented at conferences nationally or internationally. Most of these papers are included in a manuscript entitled "Air-cooled Heat Exchangers and Cooling Towers", in which Ipresent a systematic approach to the thermal performance evaluation and design of industrial air-cooled heat exchangers and cooling towers. This original publication also includes the relevant practice applicable to the design of cooling systems, based on my experience as a consultant to industry. Design offices throughout the world presently follow our design methods, or at least employ many of our research results. Our work has furthermore contributed to the development of improved cooling system designs (e.g. new dephlegmator header designs), components (e.g. single-row flattened finned tubes) and product improvement and quality control (e.g. performance testing and measurement of thermal contact resistance between fin and tube during production). Many of our research findings have found application in the modification of existing cooling systems. The manuscript has also been used as reference work during the presentation of short courses to practising engineers and consultants in industry and to engineering graduates at the University of Stellenbosch. A two-volume edition of this manuscript was published by PennWell Corp., Tulsa, Oklahoma, USA in 2004.
AFRIKAANSE OPSOMMING: Gedurende die laaste 30 jaar was ek betrokke by die teorie en praktyk van lugverkoelde warmteoordraers en koeltorings vir die kragopwekkings-, verkoelings-, proses- en petro-chemiesenywerhede in Suid-Afrika sowel as in die buiteland. Gedurende hierdie periode was ek outeur en mede-outeur van meer as 120 publikasies wat in tegniese tydskrifte, of by plaaslike of oorsese konferensies aangebied is. Die meeste van hierdie publikasies vorm deel van 'n manuskrip getiteld "Air-cooled Heat Exchangers and Cooling Towers" waarin ek 'n sistematiese benadering tot die bepaling van die termiese vermoë en ontwerp van industriële lugverkoelde warmteoordraers en koeltorings aanbied. Hierdie oorspronklike publikasie bevat ook die relevante praktyk wat van toepassing is op verkoelingsaanlegte. Ontwerpkantore wêreldwyd volg tans hierdie ontwerpsmetodes, of gebruik ten minste baie van ons navorsingsresultate. Ons werk het verder bygedra tot die ontwikkeling van verbeterde verkoelingsaanlegte (bv. nuwe deflegmatore), komponente (bv. enkelbuisry platvinbuise ) en verbeterde produkte en kwaliteitskontrole (bv. toetsing van verkoelingsvermoë oftermiese kontakweerstand tussen vin en buis gedurende produksie). Baie van ons bevindinge het toepassing gevind in die modifikasie van verkoelingsaanlegte. Die manuskrip is ook as verwysing gebruik gedurende die aanbieding van kort kursusse aan ingenieurs in die praktyk en aan nagraadse studente aan die Universiteit van Stellenbosch. 'n Twee-volume uitgawe van die manuskrip is deur PennWell Corp., Tulsa, Oklahome, VSA in 2004 gepubliseer.

The 1990 amendment to the Clean Air Act implemented a cap-and-trade system that required electricity-generating power plants to dramatically reduce Sulfur Dioxide (SO2) and Nitrogen Oxide (NOx) emissions. Plants impacted by this legislation had a variety of compliance options, including decreasing factory operation, purchasing carbon credits, installing scrubbers, and changing fuel inputs. Using data from 1997-2012 of 995 coal-burning power plants, we examine the effectiveness of scrubber installation in reducing SO2 and NOx emissions. Specifically, we employ two methods—a propensity score algorithm and a matching algorithm—to estimate: 1) the causal effect of scrubber installation prior 1997 on the emissions during 1997; and 2) the causal effect of scrubber installation at any time during the period 1997-2012 on emissions two months following scrubber installation. Using a propensity score method, we found that pre-1997 SO2 scrubbers reduced 1997 SO2 emissions by 68% (95% CI 58% to 76%), and pre-1997 NOx scrubbers reduced 1997 NOx emissions by 28% (16%, 38%). Additionally, installing SO2 and NOx scrubbers at any time during the period 1997-2012 reduces SO2 and NOx emissions by 89% (88%, 90%) and 21% (19%, 24%) two months following installation, respectively. These final two results are corroborated by a matching algorithm, which finds scrubbers cause SO2 and NOx emissions decline by 88% (87%, 89%) and by 20%. (17%, 22%) two months following installation, respectively.

Made available in DSpace on 2014-10-09T12:44:55Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:59:48Z (GMT). No. of bitstreams: 1 07173.pdf: 11277724 bytes, checksum: 5b5dfb2b888fca36e76b5cf99fdb18ab (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo

Дисертація присвячена вирішенню актуального науково-практичного питання моделювання впливу теплоенергетичних об’єктів на навколишнє природне середовище та розроблення природоохоронних заходів, що підвищують рівень екологічної безпеки в районах їх розміщення. У результаті проведених досліджень були розроблені математична модель процесу горіння в котлах із циркулюючим киплячим шаром та модель перенесення забруднювальних речовин за профілем грунту в зоні розміщення ТЕЦ. Враховуючи зміни напору та водонасиченості, що залежать від кількості опадів, клімату в цілому, спрогнозували стан підземних вод у зоні аерації досліджуваного об’єкта теплоенергетики, а також під час фільтрації води із золошлаконакопичувача. Алгоритми чисельного розв’язання задач профільної фільтрації, масоперенесення забруднювальних речовин були розроблені на базі методу скінченних елементів. Проведено дослідження утилізації відхідних газів під час деструкції палива на об’єктах теплоенергетики. Сформований механізм зв’язування азотних та сірчистих сполук у зоні деструкції палива. Запропонований режим роботи пристроїв об’єктів теплоенергетики з повною утилізацією техногенних газів. З метою оцінювання впливу на стан навколишнього природного середовища ТЕЦ, які працюють на вугіллі, та для виявлення шляхів міграції забруднювальних речовин проведені дослідження грунтів, рослинності, а також снігового покриву на вміст важких металів у районі розміщення ТЕЦ. Результати досліджень підтвердили, що підприємство негативно впливає на прилеглі території. Водночас найвищий рівень небезпеки для водних об’єктів має золошлаконакопичувач. Запропоноване влаштування захисного екрану в золошлаконакопичувачі, що зменшить техногенне навантаження місць складування золошлакових відходів на об’єкти гідросфери. Проведені дослідження підтвердили, що місцеві глинисті сорбенти можна ефективно використовувати як сорбенти. Перспективним напрямом також є перероблення золошлаків. Обстеження золошлакових відходів ТЕЦ підтвердило можливість їх використання у сфері будівництва.
Диссертация посвящена решению актуального научно-практического вопроса моделирования техногенного воздействия объектов теплоэнергетики на атмосферу и гидросферу и разработки мероприятий по повышению уровня экологической безопасности в районах их расположения. В результате проведенных исследований были разработаны математическая модель процесса горения в котлах с циркулирующим кипящим слоем и модель переноса загрязняющих веществ по почвенному профилю в зоне расположения тепловых электростанций. Учитывая изменения напора и водонасыщения, зависящие от количества осадков, климата в целом, проведено прогнозное оценивание состояния подземных вод в зоне аэрации исследуемого объекта теплоэнергетики, а также при фильтрации воды из золошлаконакопителя. Разработаны алгоритмы численного решения задач профильной фильтрации, массопереноса загрязняющих веществ на базе метода конечных элементов. Проведено исследование утилизации отходящих газов при деструкции топлива на объектах теплоэнергетики. Сформирован механизм связывания азотных и сернистых соединений в зоне деструкции топлива. Предложен режим работы устройств объектов теплоэнергетики с полной утилизацией техногенных газов. С целью оценки влияния на состояние окружающей среды работающих на угле теплоэнергетических объектов и для выявления путей миграции загрязняющих веществ исследовали почву, растительность, а также снежный покров на содержание тяжелых металлов в районе расположения ТЭЦ. Результаты исследований подтвердили, что предприятие негативно влияет на прилегающие территории. При этом самый высокий уровень опасности для водных объектов представляет золошлаконакопитель. Предложено устройство защитного экрана в золошлаконакопителе, уменьшающего техногенную нагрузку мест складирования золошлаковых отходов на объекты гидросферы. Проведенные исследования подтвердили, что местные глинистые сорбенты могут эффективно использоваться в качестве сорбентов. Перспективным направлением также является переработка золошлаков. Обследование золошлаковых отходов ТЭЦ подтвердило возможность их использования в сфере строительства.
The thesis is devoted to the solution of the urgent scientific and practical issue of modeling the technogenic impact of thermal power facilities on the atmosphere and hydrosphere and the development of measures to increase the level of environmental safety in the areas of their location. As a result of the research, a mathematical model of the combustion process in boilers with a circulating fluidized bed and a model of the transfer of pollutants along the soil profile in the area of thermal power plants were developed. Taking into account the changes in the pressure and water saturation, that are depended on the amount of precipitation and the climate as a whole, the forecast of the state of groundwater in the aeration zone of the investigated heat-power facility, as well as in the filtration of water from the ash-and-slag dump, was carried out. Algorithms for the numerical solution of the problems of profile filtration and pollutants’ mass transfer were developed based on of the finite element method. A study of the utilization of waste gases during the destruction of fuel at thermal power facilities was carried out. A mechanism for binding nitrogen and sulfur compounds in the zone of fuel destruction has been formed. The operation mode of devices of thermal power facilities with full utilization of technogenic gases is proposed. In order to assess the impact on the environment of coal-fired thermal power facilities and to identify migration paths of pollutants, soil, vegetation, and snow cover were studied for the content of heavy metals in the area of the CHPP. The research results confirmed that the enterprise has a negative impact on the nearby territories. At the same time, the highest level of danger for water bodies is posed by an ash-and-slag dump. A protective screen in the ash-and-slag dump is proposed, it will reduce the technogenic load of the ash-and-slag waste storage sites on the hydrosphere. Studies have confirmed that local clay sorbents can be effectively used as sorbents. Ash-and-slag waste processing is also a perspective area. Inspection of that wastes on CHPP confirmed the possibility of their use in the construction industry.

碩士
國立臺灣大學
環境工程學研究所
93
Taking a thermal power plant as the object of this study , its expenses on the maintenance of air-pollution protection facility and other costs such as net investment interest and depreciation are analyzed, the average annual cost of air-pollution protection was found to be NT 292 million dollars in the last five years (1998-2002). In addition , the Stratified random sampling was introduced to inquire 500 citizens of 7 districs in Keelung for conducting the questionnaire of “willing to pay price on air-quality improvement”; through the statistics regression analysis, it came to conclusion that each citizen was willing to bear his share of NT 528 dollars for “air-quality improvement”. Meanwhile , “the willing to pay price” was adjusted by introducing CPI ( commodity prices index ) and benefit transferring , the air pollution society cost of PM10 turned out to be NT 11,265 dollars per ton , NOx NT 17,611 dollars per ton , and SOx NT 112,118 dollars per ton. The average air-pollution protection benefit of this thermal power plant was NT 774 millions dollars in the last five years (1998~2002). Finally , by benefit-cost analysis, the average benefit-cost ratio of air-pollution protection in the last five years (1998~2002) was found to be 2.65.

碩士
國立交通大學
經營管理研究所
94
This thesis studies efficiency and productivity of pollution control facilities in Taiwan’s thermal power plants during the period from 2000 to 2004. Twelve sets of flue gas desulfurization (FGD) equipment in three coal-fired thermal power plants (Linkou, Taichung and Hsinta) of Taiwan Power Company (TPC) are included. The two-stage method is applied to evaluate the performance of these FGD sets. In the first stage data envelopment analysis (DEA) is used to measure the efficiency under a model with three inputs (limestone powder, operation hours, and SOx input concentration) and two outputs (SOx reduction and gypsum). Meanwhile, the Malmquist index is used to compute the productivity changes. Sensitivity and slack analyses are also discussed. In the second stage Wilcoxon test is used to test whether or not there is efficiency orderings will significantly change by adding the gypsum output. The main empirical results are as follows: 1. Most of the DMUs are at the production stage of increasing returns to scale. 2. In general, most DMUs have declining producitivity due to technical decline. 3. Efficiency orderings are sensitive to the exlusion of limestone powder and operation hours. 4. Most of the DMUs have to decrease all three inputs, in oder to improve their overall technical efficiency or pure technical efficiency. 5. Inclusion of the gypsum output will sigificantly improve the avearge performance of these FGD sets.

Air quality legislation in South Africa is entering a transformation phase, shifting the concept of atmospheric emission control towards pollution prevention and emission minimisation through a more integrated approach. This transformation, along with public pressure and increased foreign trade, is providing industries with incentives to consider their effect on the environment and to take action where required. To assist South African industries in determining what air pollution control technologies are best suited to power plants, gasification and refining processes in South Africa; an assessment of air pollution control technologies used in other countries was carried out. This assessment concluded that the best available technologies for power plants to control air emissions are electrostatic precipitators, low-NOx burners, selective catalytic reduction systems and wet flue gas desulphurisation (limestone) systems. For gasification processes it was found that the main air pollution contributor is the gas handling and treatment process. Releases from this process are controlled through dust collection, wet scrubbing, conversion of sulphide compounds, sulphur recovery and the incineration of final vent gases before release to the atmosphere. For refining processes the catalytic cracking unit is normally the largest single air emission source and controlling emissions from this unit avoids controlling multiple minor sources. Emissions from this unit are controlled via wet scrubbing, selective catalytic reduction systems and carbon monoxide boilers. An assessment of the financial effects associated with air pollution control at power plants was conducted by completing a cost analysis. This analysis demonstrated that by increasing capital expenditure on control technologies by R 1,7 billion, the external costs associated with producing electricity can be reduced by almost R 3,4 billion. Formulation of external cost factors for South African conditions, and the development of a software database for the information obtained from the different countries, will promote future technology selections.
Dissertation (MASTER OF ENGINEERING(Environmental Engineering))--University of Pretoria, 2007.
Chemical Engineering
unrestricted

Lephalale Municipality is a predominantly rural Municipality with 38 villages, two townships (Marapong and Onverwacht) and one town, Lephalale. Lephalale, formerly known as Ellisras, is a town situated in the “heart of the Bushveld” in Limpopo province. The town is growing rapidly and more industries are becoming concentrated within this small town. The construction of Medupi power station which is underway and other projects such as the expansion of Grootegeluk mine (coal 3 and 4 projects), and road developments in the area; have led to concern about the ambient air quality of the area. Other possible future projects are the Coal to Liquid project by Sasol and the Coal Bed Methane project by Anglo American Thermal Coal. The purpose of this study is to determine the ambient air quality impact of the Matimba power station in the Lephalale area. The AERMOD model and ambient air quality data obtained from Eskom’s Grootstryd and Marapong monitoring stations were used to assess the ambient air quality of Lephalale. Sulphur dioxide and Nitrogen oxides were investigated. Both the model’s results and the ambient air quality monitoring data indicated that the power station contributes to high -ground level concentrations of Sulphur dioxide. AERMOD simulated the nitrogen oxides results as nitrogen dioxide. From the study it is concluded that the power station is not the only source of nitrogen oxides. Nitrogen oxides concentrations were associated with low-level sources. The relationship between the criteria pollutants in this study was assessed. The study found that there is no relationship between sulphur dioxide and nitrogen oxides. This finding was used to support the idea that sulphur dioxide and nitrogen oxides are from different sources. It was also established that seasonality has an influence on the ground level concentrations of pollutants in the area.

碩士
國立成功大學
工學院工程管理專班
91
The objective of the study is based on the air pollution prevention policy of Taiwan Power Company (T.P.C.) in recent years. In this research, it studies the various methodologies of reducing pollution for both of SOx and CO2. Also, evaluating the environmental effect cost for them. This research proposes the best available techniques of implement to reduce equipment with evaluation process framework. Firstly, with the AHP methodology to estimate the various methods of reducing pollution by the using of five factors, such as equipment cost, reducing function, reliability, environmental risk, and uncertain policy risk in three sides. According to the evaluation of AHP, the theory that take better available techniques of reducing equipment as the priority. Secondly, put to use the cost of the unit power generation and the cost of equipment asset to calculate the cost ratio in the equipment before and after investment with the better available techniques of reducing equipment. If the cost of the investment is no benefit, simulate the environment effect cost within three differential scenarios, then to calculate them. The analysis of process framework shows that if the environment effect cost is greater than the cost equipment asset, so we take the evaluating process eventually obtains the best available techniques (B.A.T) of reducing equipment. Finally, by utilizing both of SOx and CO2 approves to show the practical procedures of design for evaluation process framework. Hopefully, this research result can be used as the reference for future policy in air pollution prevention and provides worthwhile suggestions for Taiwan Power Company.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science June 2015
Lephalale is the home of Matimba, one of Eskom’s coal-fired power stations. Matimba is the biggest power station with a dry cooling system in the world. There are other industries (including coal mines) currently in operation in close proximity to the station. This industrial area is expected to grow as more industrial activities are planned for the following years. These activities will aggravate the levels of air pollution and possibly result in it being a “hot spot” for air pollution. The impact of air quality on health is covered by the National Ambient Air Quality Standards (NAAQS), but the impact of air quality on the terrestrial and aquatic ecosystem is not known. Therefore, this study focuses on the deposition of nitrogen oxides (NOx) (as nitrogen dioxide (NO2)) and sulphur dioxide (SO2) within Lephalale in the Waterberg-Bojanala Priority Area. Additionally, inter-annual variability of NOx and SO2 ambient concentrations and back trajectories of air masses were analysed. The study obtained ambient air quality data and meteorological data from Eskom for the period 2008–2012, while additional meteorological data were obtained from the Agricultural Research Council (ARC) and the South African Weather Service (SAWS). An inferential model was used to estimate the dry deposition flux of SO2 and NOx (as NO2), and the Hybrid Single Particle Langrangian Integrated Trajectory (Hysplit) Model was used to cluster back trajectories of air masses. The results of the seasonal dry deposition velocities of SO2 (0.17 to 0.23 cm/s) and NOx (0.10 to 0.15 cm/s) (as NO2) were higher in summer and lower in winter. They were also within the magnitude of the deposition velocities found in previous studies in the Highveld. The high deposition velocities in summer were attributed to photosynthetically active vegetation, turbulence and solar radiation. However, seasonal dry deposition fluxes of SO2 and NOx were higher in winter across the years. The higher flux values in winter were attributed to higher ambient concentrations of the trace gases. Additionally, the annual dry deposition flux of SO2 ranged between 0.43 and 0.67 kg S ha-1 yr-1, while NOx (as NO2) ranged between 0.84 and 1.05 kg N ha-1 yr-1 over the period studied. The annual deposition flux values found in the current study are lower than those found in previous studies in the Highveld. This difference could be because of the lower ambient concentrations of SO2 and NOx observed in this study. There is an inter-annual variability of the ambient concentrations of SO2 and NOx during the period 2008–2012. However, the difference is not large or statistically significant. The dominant direction of the back trajectories of air masses is east and southeast across all seasons for the entire period of 2008–2012. This lack of seasonal pattern in back trajectories and source regions cannot explain the seasonal changes in ambient concentrations (SO2 and NOx). Hence, climatic factors (e.g. change in weather) or seasonal changes in combustion source intensity must be responsible.