Dissertations / Theses: 'Coal-fired power plant; biomass'

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Arcot, Vijayasarathy Udayasarathy. "Mercury emission control for coal fired power plants using coal and biomass." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2535.

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Arumugam, Senthilvasan. "Nitrogen oxides emission control through reburning with biomass in coal-fired power plants." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1508.

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Oxides of nitrogen from coal-fired power stations are considered to be major pollutants, and there is increasing concern for regulating air quality and offsetting the emissions generated from the use of energy. Reburning is an in-furnace, combustion control technology for NOx reduction. Another environmental issue that needs to be addressed is the rapidly growing feedlot industry in the United States. The production of biomass from one or more animal species is in excess of what can safely be applied to farmland in accordance with nutrient management plans and stockpiled waste poses economic and environmental liabilities. In the present study, the feasibility of using biomass as a reburn fuel in existing coal-fired power plants is considered. It is expected to utilize biomass as a low-cost, substitute fuel and an agent to control emission. The successful development of this technology will create environment-friendly, low cost fuel source for the power industry, provide means for an alternate method of disposal of biomass, and generate a possible revenue source for feedlot operators. In the present study, the effect of coal, cattle manure or feedlot biomass, and blends of biomass with coal on the ability to reduce NOx were investigated in the Texas A&M University 29.31 kW (100,000 Btu/h) reburning facility. The facility used a mixture of propane and ammonia to generate the 600 ppm NOx in the primary zone. The reburn fuel was injected using air. The stoichiometry tested were 1.00 to 1.20 in the reburn zone. Two types of injectors, circular jet and fan spray injectors, which produce different types of mixing within the reburn zone, were studied to find their effect on NOx emissions reduction. The flat spray injector performed better in all cases. With the injection of biomass as reburn fuel with circular jet injector the maximum NOx reduction was 29.9 % and with flat spray injector was 62.2 %. The mixing time was estimated in model set up as 936 and 407 ms. The maximum NOx reduction observed with coal was 14.4 % and with biomass it was 62.2 % and the reduction with blends lay between that of coal and biomass.

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Wang, Dongcan. "Comparative analysis of development potential for biomass- vs coal-fired powerplants in Henan province,China." Thesis, KTH, Energiteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211707.

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Coal-fired power plants’ typically large capacity and relatively low electricity generation costs in the Chinese power market can be compared with their typically low specific thermal efficiency and older age on average. At the same time, the environment pollution caused by local coal-fired power plants has started to receive due attention. Sustainable renewable energy sources and the application of effective conversion technologies for those has become a top priority of China's current energy strategy. Biomass in general and anaerobic biogas in particular can be regarded as clean, locally available renewable energy resources. Replacing coal with biomass-derived energy is especially relevant for certain locations in China. For the case of Henan province, work has already been undertaken by the local authorities for the proper estimation of the biomass potential and the selection of most applicable energy conversion technologies with the lowest environmental footprint to replace aging coal-fired plants with various biomass-based power generation facilities.
Kolkraftverkens typiska stora kapacitet och relativt låga elproduktionskostnader på den kinesiska elmarknaden kan jämföras med deras typiskt låga specifika verkningsgrader och äldre ålder i genomsnitt. Samtidigt har miljöföroreningarna som orsakas av lokala kolkraftverk börjat uppmärksammas på riktigt i Kina. Hållbara förnybara energikällor och tillämpningen av effektiv konverteringsteknik för dessa har blivit en topprioritet för Kinas nuvarande energistrategi. Biomassa i allmänhet och anaerobisk biogas (rötgas) i synnerhet kan betraktas som rena och lokalt tillgängliga förnybara energiresurser. Byte av kol mot biobränslen blir särskilt relevant för vissa platser i Kina. När det gäller Henanprovinsen har en del arbete redan gjorts av de lokala myndigheterna för en korrekt uppskattning av biomasspotentialen och en analys av de mest tillämpliga teknologier för omvandling av bioenergi med lägsta miljöpåverkan som ersätter åldrande koleldade anläggningar med olika biobränslen.

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Asgaryan, Mohammad. "Prediciton of the remaining service life of superheater and reheater tubes in coal-biomass fired power plants." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8278.

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As a result of concern about the effects of CO2 emssions on the global warming, there is increasing pressure to reduce such emissions from power generation systems. The use of biomass co-firing with coal in conventional pulverised fuel power plants has provided the most immediate route to introduce a class of fuel that is regarded as both sustainable and carbon neutral as it produces less net CO2 emissions. In the future it is anticipated that increased levels of biomass will be required to use in such systems to accomplish the desired CO2 emissions targets. The use of biomass, however, is believed to result in severe fireside corrosion of superheater and reheater tubing and cause unexpected early failures of tubes, which can lead to significant economic penalties. Moreover, future pulverised fuel power systems will need to use much higher steam temeptures and pressures to increase the boiler efficiency. Higher operating temperatures and pressures will also increase the risk of fireside corrosion damage to the boiler tubing and lead to shorter component life. Predicting the remaining service life of superheater and reheater tubes in coal-biomass fired power plants is therefore an important aspect of managing such power plants. The path to this type of failure of heat exchangers involves five processes: combustion, deposition, fireside corrosion, steam-side oxidation, and creep. Various models or partial models each of these processes are available from existing research, but to fully understand the impact of new fuel mixtures (i.e. biomass and coal) and changing operating conditions on such failures, an integrated model of all of these processes is required. This work has produced an integrated set of models and so predicted the remaining service life of superheater/reheater tubes based on the three frameworks which have been developed by analysing those models used in depicting the five processes: one was conceptual and the other two were based on mathematical model. In addition, the outputs of the integrated mathematical models were compared with the laboratory generated data from Cranfield University as well as historical data from Central Electricity Research Laboratories. Furthermore, alternative models for each process were applied in the model and the results were compared with other models results as well as with the experimental data. Based on these comparisons and the availability of models constants the best models were chosen in the integrated model. Finally, a sensitivity analysis was performed to assess the effect of different model input values on the residual life superheater and reheater tubing. Mid-wall metal temperature of tubes was found to be the most important factor affecting the remaining service life of boiler tubing. Tubing wall thickness and outer diameter were another critical input in the model. Significant differences were observed between the residual life of thin-walled and thick-walled tubes.

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Alipour, Yousef. "High temperature corrosion in a biomass-fired power boiler : Reducing furnace wall corrosion in a waste wood-fired power plant with advanced steam data." Licentiate thesis, KTH, Yt- och korrosionsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121155.

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The use of waste (or recycled) wood as a fuel in heat and power stations is becoming more widespread in Sweden (and Europe), because it is CO2 neutral with a lower cost than forest fuel. However, it is a heterogeneous fuel with a high amount of chlorine, alkali and heavy metals which causes more corrosion than fossil fuels or forest fuel. A part of the boiler which is subjected to a high corrosion risk is the furnace wall (or waterwall) which is formed of tubes welded together. Waterwalls are made of ferritic low-alloyed steels, due to their low price, low stress corrosion cracking risk, high heat transfer properties and low thermal expansion. However, ferritic low alloy steels corrode quickly when burning waste wood in a low NOx environment (i.e. an environment with low oxygen levels to limit the formation of NOx). Apart from pure oxidation two important forms of corrosion mechanisms are thought to occur in waste environments: chlorine corrosion and alkali corrosion. Although there is a great interest from plant owners to reduce the costs associated with furnace wall corrosion very little has been reported on wall corrosion in biomass boilers. Also corrosion mechanisms on furnace walls are usually investigated in laboratories, where interpretation of the results is easier. In power plants the interpretation is more complicated. Difficulties in the study of corrosion mechanisms are caused by several factors such as deposit composition, flue gas flow, boiler design, combustion characteristics and flue gas composition. Therefore, the corrosion varies from plant to plant and the laboratory experiments should be complemented with field tests. The present project may thus contribute to fill the power plant corrosion research gap. In this work, different kinds of samples (wall deposits, test panel tubes and corrosion probes) from Vattenfall’s Heat and Power plant in Nyköping were analysed. Coated and uncoated samples with different alloys and different times of exposure were studied by scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), X-ray diffraction (XRD) and light optical microscopy (LOM). The corrosive environment was also simulated by Thermo-Calc software. The results showed that a nickel alloy coating can dramatically reduce the corrosion rate. The corrosion rate of the low alloy steel tubes, steel 16Mo3, was linear and the oxide scale non-protective, but the corrosion rate of the nickel-based alloy was probably parabolic and the oxide much more protective. The nickel alloy and stainless steels showed good corrosion protection behavior in the boiler. This indicates that stainless steels could be a good (and less expensive) alternative to nickel-based alloys for protecting furnace walls. The nickel alloy coated tubes (and probe samples) were attacked by a potassium-lead combination leading to the formation of non-protective potassium lead chromate. The low alloy steel tubes corroded by chloride attack. Stainless steels were attacked by a combination of chlorides and potassium-lead. The Thermo-Calc modelling showed chlorine gas exists at extremely low levels (less than 0.1 ppm) at the tube surface; instead the hydrated form is thermodynamically favoured, i.e. gaseous hydrogen chloride. Consequently chlorine can attack low alloy steels by gaseous hydrogen chloride rather than chlorine gas as previously proposed. This is a smaller molecule than chlorine which could easily diffuse through a defect oxide of the type formed on the steel.

QC 20130423

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Ozcan, Dursun Can. "Techno-economic study of the calcium looping process for CO2 capture from cement and biomass power plants." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/10455.

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The first detailed systematic investigation of a cement plant with various carbon capture technologies has been performed. The calcium looping (Ca-looping) process has emerged as a leading option for this purpose, since this process applied to a cement plant provides an opportunity to use the CaO purge for clinker production. The Ca-looping process is comprised of two interconnected reactors where the carbonator captures CO2 from flue gases and the calciner regenerates the CaCO3 into CaO by oxy-combustion. Fully integrated process flowsheets have been developed and simulated in UniSim Design Suite from Honeywell. The detailed carbonator model has been implemented using Matlab and incorporated into UniSim to provide a full flowsheet simulation for an exemplary dry-feed cement plant as a user-defined operation. The base cement plant simulation was also modified to integrate three different carbon capture processes: membrane; indirect calcination; and amine-scrubbing. Furthermore, an advanced configuration of Ca-looping process has been investigated where the energy intensive air separation unit was replaced with a chemical looping combustion (CLC) cycle. Each case has been optimised to minimise its energy consumption and compared in terms of levelised cost of cement and its resulting cost of CO2 avoided at the same CO2 avoidance rate. The proposed integration of the Ca-looping process is capable of achieving over 90% CO2 avoidance with additional fuel consumption of 2.5 to 3.0 GJth/ton CO2 avoided. By using an advanced configuration of the Ca-looping process with a CLC cycle, the additional fuel consumption can be reduced to 1.7 GJth/ton CO2 avoided, but the cost of the oxygen carrier is the major concern for this system. Among the other CO2 capture options, the membrane process is a promising alternative for the Ca-looping process since it has a potential of achieving the target CO2 avoidance rate and purity requiring lower energy consumption. The indirect calcination process provides moderate levels of CO2 avoidance (up to 56%) without a need of an external capture process whereas the integration of the amine process in a cement plant is challenging as a result of the requirement of steam for solvent regeneration. Furthermore, considering zero net CO2 emissions associated with biomass combustion systems, a novel concept has been analysed to capture of CO2 in-situ with the Ca-looping process while operating the combustor of a dedicated biomass power plant at sufficiently low temperature. This process is capable of achieving 84% overall CO2 capture rate with an energy penalty of 5.2% when a proper heat exchanger network is designed with the support of a pinch analysis. The techno-economic performance of the biomass power plant with in-situ Ca-looping CO2 capture process was compared with that of the alternative biomass-air-fired and biomass-oxy-fired power plants.

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Lay, Victoria F. "The affect of ash chemistry and deposits from co-firing biomass and coal in power plant systems." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/32154.

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Hemp, eucalyptus, coal, hemp and coal blended fuel, and eucalyptus and coal blended fuel were ashed and then heat treated for 1 hour at temperatures from 600-1100°C. X-ray diffraction analysis indicated reactions between the phases present after initial ashing of the fuel showed biomass-biomass, biomass-coal and coal-coal interactions. Two phase systems were identified as dominant in the biomass and coal ash blends, these were CaO-MgO-SiO2 and CaO-Al2O3-SiO2. The phases identified in these systems have also been identified in ceramics produced at high temperatures which have similar compositions to the ash matrix of the laboratory synthesised ash; this indicates that phase diagrams can be powerful tools in phase formation prediction. Structures identified as trichomes (phosphate-silicate structures with melting points above 1100°C) from the hemp fuel which had not decomposed were present in both the hemp ash and the hemp and coal ash. The composition determined by Energy-dispersive X-ray spectroscopy analysis of laboratory synthesised ashes was also in agreement with the phases identified through X-ray diffraction. Hemp and coal, eucalyptus and coal, and eucalyptus ash samples (deposited, quenched, cyclone, and bottom ash) removed from a full scale 1MWth combustion rig were analysed. Phase composition of the fly ash samples are similar to those identified in the analagous samples produced in the laboratory with several of the same phases present; confirming that laboratory testing is useful for the predictions of phases present on the industrial scale combustion rig. Particle morphology is one of the largest differences between the laboratory scale tests and combustion rig samples. The dominant particle shape of fly ash particles removed from the combustion rig is spherical. These particles of characteristic shape are often referred to as plerospheres and cenospheres and were first identified in coal fly ash. The presence of the spheres in the combustion rig when only biomass (eucalyptus) is present indicates the formation mechanism of the particles is similar to that of coal. There are similarities between the chemical composition of the spheres which are solely of biomass origin and co-fired; it is likely that phase composition of the sphere and not the fuel origin contributes to the formation of the spheres. Phases identified in the bottom ash are similar to those identified in the fly ash. High temperature phases such as (e.g. Ca9MgK(PO4)7) ocur in the bottom ash suggesting that higher temperatures are reached in the bottom of the rig than in the flue gas. Analysis of 15Mo3 alloy corrosion coupons with fly ash deposited onto the surface, alongside the interactions between gas phases and coupons, deposits and coupons, and gas phases and deposits, showed that some oxidation/reduction of the metal had occurred. The presence vi of metal oxide flakes indicated corrosion. Oxidation of 15Mo3 alloy was observed in hemp and coal, and eucalyptus and coal combustion trials, likely due to the observed deposition of potassium chloride which has caused detachment of several scales. Between the metal-deposit interface, hematite whiskers were observed; magnetite octahedra were also present on the surface of scales. The phases present in the coupon deposit ash differ from those observed in the laboratory and fly ash due to the length of time spent in the high temperature environment. This indicates that some phases will not form until the deposits have built up and are in the furnace for an extended period of time. When the coupon samples were coated, fewer metal scales were observed meaning that the coatings are an affective method of corrosion reduction leading to an increased lifetime of boiler components. The dominant particle morphology present in the combustion rig is the cenospheres and plerospheres. The phases formed can be broadly catergorised into CaO-MgO-SiO2, CaO-Al2O3-SiO2, and K2O-Al2O3-SiO2 phases. Potassium chloride is observed in the laboratory ash and combustion rig ash indicating, alongside the presence of metal oxide scales, that the fuel blends are likely to lead to corrosion during combustion.

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Sasi, Giuma A. A. "Evaluation Of Metal Concentrations In Groundwater Nearby Soma Coal-fired Power Plant." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606756/index.pdf.

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ABSTRACT EVALUATION OF METAL CONCENTRATIONS IN GROUNDWATER NEARBY SOMA COAL FIRED POWER PLANT Giuma Sasi M.S., Department of Chmistry Supervisor: Prof. Dr. Semra G. Tuncel December 2005, 95 Pages In this work, metal pollution in groundwater near by Soma coal-fired power plant was invistigated. Coal combustion results in huge amounts of bottom ash from which metals can originate and migrate to groundwater and pollute it. Forty groundwater samples were collected from water wells in an area near by the power plant to determine 14 metals namely
Na, Ca, K, Mg, Al, Ba, Fe, Zn, Cu, Pb, Cr, Cd, Ni and V. Samples were collected in polyethylene bottles, the pH of the water was measured. Then, the samples were acidified and stored to be analyzed. FAAS, FAES, GFAAS and ICP-AES were used to determine the elements. The results were compared with the WHO, the Turkish and EC guidelines for drinking water quality. Fe concentrations in 12 wells were higher the three guidelines. Zn concentrations in 5 wells were higher than the EC guidelines, but not higher than the Turkish guidelines. Pb concentrations was less than all guilelines but it was relatively high in 8 wells. The other anthropogenic elements were lower than all guidelines but these metals tend to accumulate and they will exceed the guildlines overtime. Enrichment factor calculations showed that the anthropogenic elements were enriched in the regions close to the ash piles pointing out that the ash piles are the main source of these elements. Factor analysis was applied and four main factors of the determined metals were found indicating that the power plant and the ash piles are the main source for the anthropogenic elements.

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Vir, Arun. "Solar Booster Augmentation for Existing Coal Fired Power Plant (A Feasibility Study)." Thesis, KTH, Kraft- och värmeteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-103911.

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The fast depletion of fossil fuel has increased the havoc and need of finding an alternative for the existing fossil fuel based energy industry. As a result, many renewable energy sources such as Solar, Wind, Geo Thermal, Bio mass, etc... are being looked in to. One of the major sources of renewable energy is our sun. There are two methods of tapping the energy from the sun. 1. Solar Thermal It involves using the sun’s heat directly in some processes or indirectly to produce electricity. 2. Photo Voltaic It involves using the light to produce electricity using Photo Voltaic cells. This report involves only the Solar Thermal part where the sun’s heat is indirectly used to produce electricity. This report focuses mainly on a method known as Compact Linear Fresnel Reflectors (CLFR). This method involves the focusing of sun’s energy to an over head tube through mirrors arranged to form the shape similar to that of a Fresnel lens and hence the name. Water runs in the over head tube, the focused energy from the sun, heats up the over head tube and produces steam which in turn runs a steam turbine which in turn produces electricity. This report focuses mainly the potential of using CLFR technology to be augmented in to existing coal fired power plants in India. India has a solar reception of 5 Peta watt hours per year with an average of 4 – 7 kW/m2 DNI. One of National Thermal Power Corporation’s Coal fired thermal power station, Dadri Thermal Power Station, has been chosen for the purpose of case study for this particular thesis. Since there is coal shortage at the power plant location and the plant is not able to produce the peak load, our primary objective was to achieve the production of peak load. The existing power cycle and the solar steam augmented power cycles have been simulated using Thermoflow software and the results have been tabulated.

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Syed, Muzaffar Ali. "CO2-fuel gas separtationfor a conventional coal-fired power plant (first approach)." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18705.

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In order to mitigate climate change, there is a desperate need to reduce CO2 emissionsfrom different sources. CO2 capture and sequestration will play an important role in thesereductions. This report is focused on the capture of CO2 from flue gas emitted by a coalfired power plant, which is also described in this report. From the available technologies,post combustion capture with chemical absorption is chosen. It is already been shown byprevious work that it is possible to capture CO2 by this method; this report goes a stepahead to simulate this process. Various methods available are described briefly alongwith the justification why 30% (wt) MEA is used as solvent for this kind of process. Afirst approach is made towards the simulation of the process using Aspen Plus 2006. Themass balance and the energy required for the process have been calculated. Forsimulation the help was taken from Aspen Plus 2006 documentation, also previous workassisted in performing it. The results obtained can be used as the base for optimizing thesimulation.
Uppsatsnivå: D

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Smith, P. J. "Predicting hot corrosion rates under coal fired combined cycle power plant conditions." Thesis, Cranfield University, 1994. http://dspace.lib.cranfield.ac.uk/handle/1826/10512.

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Type 11 hot corrosion has been identified as a major life limiting factor of gas turbine components in the topping cycle of coal fired combined cycle power plant. Impurities in the coal combustion gases provide the environmental contaminants necessary for type 11 hot corrosion to occur. It is the purpose of the present study to develop corrosion lifting models such that corrosion rates and thus component lives in coal fired combined cycle plant gas turbines may be accurately predicted thus minimising efficiency losses and plant downtime due to corrosion related problems. Type 11 hot corrosion has been shown to follow bi11lodal distributions which cannot be modelled using the well known mathematical models. It has been shown that a probabilistic approach to modelling is appropriate and that the Gumbel Type I extreme value model of maxima can be used to model the maximum extreme corrosion data This is appropriate as it is the maximum extreme corrosion which in life limiting in the plant gas turbine. Basic corrosion data has been generated through a series of laboratory hot corrosion tests designed to simulate the ambient conditions within the plant gas turbine. The variables having most influence on the corrosion process have been identified as ; temperature, thermal cycling, alkali (Na + K) metal sulphate deposition rate, S02 and HCl in the ambient atmosphere. The corrosion models have been developed from this data which accurately predict the type 11 hot corrosion rates observed in the coal fired gas turbine of a combined cycle power plant .

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Paredez, Jose Miguel. "Coal-fired power plant flue gas desulfurization wastewater treatment using constructed wetlands." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18255.

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Master of Science
Department of Civil Engineering
Natalie Mladenov
In the United States approximately 37% of the 4 trillion kWh of electricity is generated annually by combusting coal (USEPA, 2013). The abundance of coal, ease of storage, and transportation makes it affordable at a global scale (Ghose, 2009). However, the flue gas produced by combusting coal affects human health and the environment (USEPA, 2013). To comply with federal regulations coal-fired power plants have been implementing sulfur dioxide scrubbing systems such as flue gas desulfurization (FGD) systems (Alvarez-Ayuso et al., 2006). Although FGD systems have proven to reduce atmospheric emissions they create wastewater containing harmful pollutants. Constructed wetlands are increasingly being employed for the removal of these toxic trace elements from FGD wastewater. In this study the effectiveness of using a constructed wetland treatment system was explored as a possible remediation technology to treat FGD wastewater from a coal-fired power plant in Kansas. To simulate constructed wetlands, a continuous flow-through column experiment was conducted with undiluted FGD wastewater and surface sediment from a power plant in Kansas. To optimize the performance of a CWTS the following hypotheses were tested: 1) decreasing the flow rate improves the performance of the treatment wetlands due to an increase in reaction time, 2) the introduction of microbial cultures (inoculum) will increase the retention capacity of the columns since constructed wetlands improve water quality through biological process, 3) the introduction of a labile carbon source will improve the retention capacity of the columns since microorganisms require an electron donor to perform life functions such as cell maintenance and synthesis. Although the FGD wastewater collected possessed a negligible concentration of arsenic, the mobilization of arsenic has been observed in reducing sediments of wetland environments. Therefore, constructed wetlands may also represent an environment where the mobilization of arsenic is possible. This led us to test the following hypothesis: 4) Reducing environments will cause arsenic desorption and dissolution causing the mobilization of arsenic. As far as removal of the constituents of concern (arsenic, selenium, nitrate, and sulfate) in the column experiments, only sulfate removal increased as a result of decreasing the flow rate by half (1/2Q). In addition, sulfate-S exhibited greater removal as a result of adding organic carbon to the FGD solution when compared to the control (at 1/2Q). Moderate selenium removal was observed; over 60% of selenium in the influent was found to accumulate in the soil. By contrast, arsenic concentrations increased in the effluent of the 1/2Q columns, most likely by dissolution and release of sorbed arsenic. When compared to the control (at 1/2Q), arsenic dissolution decreased as a result of adding inoculum to the columns. Dissolved arsenic concentrations in the effluent of columns with FGD solution amended with organic carbon reached 168 mg/L. These results suggest that native Kansas soils placed in a constructed wetland configuration and amended with labile carbon do possess an environment where the mobilization of arsenic is possible.

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Sekar, Ram C., John E. Parsons, Howard J. Herzog, and Henry D. Jacoby. "Future Carbon Regulations and Current Investments in Alternative Coal-Fired Power Plant Designs." MIT Joint Program on the Science and Policy of Global Change, 2005. http://hdl.handle.net/1721.1/30594.

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This paper assesses the role of uncertainty over future U.S. carbon regulations in shaping the current choice of which type of power plant to build. The pulverized coal technology (PC) still offer the lowest cost power— assuming there is no need to control emissions of carbon. The integrated coal gasification combined cycle technology (IGCC) may be cheaper if carbon must be captured. Since a plant built now will be operated for many years, and since carbon regulations may be instituted in the future, a U.S. electric utility must make the current investment decision in light of the uncertain future regulatory rules. This paper shows how this decision is to be made. We start by describing the economics of the two key coal-fired power plant technologies, PC and IGCC. We then analyze the potential costs of future carbon regulations, including the costs of retrofitting the plant with carbon capture technology and the potential cost of paying charges for emissions. We present the economics of each design in the form of a cash flow spreadsheet yielding the present value cost, and show the results for different scenarios of emissions regulation. We then discuss how to incorporate uncertainty about the future regulation of carbon emissions into the decision to build one plant design or the other. As an aid to decision making, we provide some useful benchmarks for possible future regulation and show how these benchmarks relate back to the relative costs of the two technologies and the optimal choice for the power plant investment. Few of the scenarios widely referenced in the public discussion warrant the choice of the IGCC technology. Instead, the PC technology remains the least costly. The level of future regulation required to justify a current investment in the IGCC technology appears to be very aggressive, if not out of the question. However, the current price placed on carbon emissions in the European Trading System, is higher than these benchmarks. If it is any guide to possible future penalties for emissions in the U.S., then current investment in the IGCC technology is warranted.
Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).
This research was supported by the MIT Joint Program on the Science and Policy of Global Change and the MIT Carbon Sequestration Initiative. The MIT modeling facility used in this analysis was supported by the US Department of Energy, Office of Biological and Environmental Research [BER] (DE-FG02-94ER61937), the US Environmental Protection Agency (XA-83042801-0), the Electric Power Research Institute, and by a consortium of industry and foundation sponsors.

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Brajkovic, Jurica. "Evaluating investment in base load coal fired power plant using real options approach." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/171553/.

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This thesis investigates the impact of uncertainty on investment in a coalfired power plant using a real options (RO) framework. It is organized in five chapters. In the first chapter I give an outline of the thesis. In Chapter 2 I review the background material. I describe the electricity sector in the pre- and post-liberalization periods and discuss the implication of the transition on investment in new generation capacity. Further, I analyze the mainstream approach to investment analysis used by the majority of electricity companies, the discounted cash flow (DCF) approach. Next, I describe an alternative approach for evaluating investments, RO. In Chapter 3 I perform an econometric analysis of dark spread prices. I select four different stochastic processes and fit them to the observed data. The goal is to find which of the four processes (arithmetic Brownian motion (ABM), Ornstein-Uhlenbeck (OU), Cox-Ingersoll-Ross (CIR) and the Schwartz one-factor process) can best describe the evolution of dark spread prices. The analysis shows that the CIR process is the most appropriate model to use to represent the evolution of dark spread prices. In Chapter 4 I evaluate an investment in a coal-fired power plant assuming the dark spread is the only source of uncertainty and using the stochastic processes for which I estimated parameters in Chapter 3. First I calculate the optimal investment threshold using a traditional budgeting approach based on the DCF principle. Following this, using the RO framework, I calculate the optimal investment threshold for the four stochastic processes. I conclude that one should use mean reverting process to model the investment decision but the choice of mean reverting process does not significantly affect the investment threshold values. In Chapter 5 I extend the analysis and model coal and electricity prices separately. Now the investment decision is affected by two factors: the price of electricity (output) and the price of coal (input). The goal of this chapter is to analyze whether this increase in complexity (going from a one-factor to a two-factor model) affects the result obtained in the previous chapter. Given the different dynamics of electricity and coal prices, I find that this approach enriches the investment analysis and gives additional insights. In particular, the higher the coal price, the greater the dark spread needs to be in order to undertake the investment. Finally, Chapter 6 concludes. The thesis contributes to the existing knowledge in several ways. RO have been applied to the electricity sector before, but this is the first time they have been applied to the evaluation of investment in a coal-fired power plant. Secondly, this is the first time that dark spread, electricity and coal prices are modeled for use in a RO analysis. Finally, the thesis provides a comparison of investment analysis for a coal-fired power plant using RO based on single and two state variables, which has not been carried out so far.

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Agbonghae, Elvis Osamudiamen. "Modelling and optimization of coal-fired power plant generation systems with CO2 capture." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/7816/.

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This thesis investigates the capture of CO2 from the flue gas of coal-fired power plants using an aqueous solution of MEA, and the main aim of this thesis is the development of an optimized amine-based post-combustion CO2 capture (PCC) process that can be integrated optimally with a pulverized coal-fired power plant. The relevance of this thesis cannot be overemphasised because the reduction of solvent regeneration energy is the focus of most of the solvent-based post-combustion CO2 capture (PCC) research currently being performed globally. From the view point of current research and development (R&D) activities worldwide, three main areas are being investigated in order to reduce the regeneration energy requirement of an amine-based PCC process, namely: (i) development of new solvents with better overall performance than 30 wt% monoethanolamine (MEA) aqueous solution, (ii) PCC plant optimization, and (iii) optimal integration of the PCC Plant, including the associated CO2 compression system, to the upstream power plant. In this thesis, PCC plant optimization and the optimal integration of an optimized PCC Plant, including the associated CO2 compression system, with an upstream coal-fired power plant has been investigated. Thus, an integrated process comprising ~550 MWe (net power after CO2 capture and compression) pulverized coal-fired (PC-fired) supercritical power plant, an MEA-based post-combustion capture (PCC) plant and a CO2 compression system has been modelled, simulated and optimized. The scale-up design of the PCC plant was performed using a novel method based on a rate-based calculation and thus the unnecessary over-design of the PCC plant columns was avoided. Furthermore, because of the importance of the operating pressure of the stripper in a PCC plant integrated to a PC-fired power plant, the impact of the operating pressure of the stripper on the net plant efficiency of the integrated system has been quantified. Also, the impacts of coal type on the overall performance of the integrated process have been quantified.

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Ihiabe, Daniel. "Assessing biomass-fired gas turbine power plants : a techno-economic and environmental perspective." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8451.

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Fossil fuels continue to deplete with use as they are irreplaceable. In addition, the environmental impact with the continuous use of these conventional fuels has generated global concern due to the production of harmful emission gases. An alternative source of energy has become inevitable. Technological advancements in the area of biomass use for both aviation and power generation are at different levels of development. There is however the need for an integrated approach to assess gas turbine engine behaviour in terms of performance, emission and economics when they are running on biofuels. The current research work is concerned with finding alternative fuel resources for use on stationary gas turbine engines for power generation with the necessary identification of suitable biofuels using a multidisciplinary approach. A techno-economic, environmental and risk assessment (TERA) model comprising the performance, emissions, economics and risk modules has been developed. There had been several simulations of two gas turbine engines (GTEs) to ascertain the effects of both ambient and operating conditions and the effect of fuel types on the engines. These simulations were done with the use of an in-house code-the Turbomatch and a code developed for the steam cycle which is employed for the combined cycle simulation. Cont/d.

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Schuhbauer, Christian [Verfasser]. "Dynamic and Coupled Simulation of the 700°C Coal-Fired Power Plant / Christian Schuhbauer." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045988774/34.

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Shimeles, Surafel. "Thermo-economic Analysis of Retrofitting an Existing Coal-Fired Power Plant with Solar Heat." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17216.

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At a time when global environmental change is posing a growing challenge to the world’s economy and creating uncertainties to livelihood of its inhabitants, Coal thermal power plants are under pressure to meet stringent environmental regulations into achieving worldwide set millennial goals for mitigating the effect of emission gases on the atmosphere. Owing to its abundance, it is unlikely to see the use of coal completely missing from the global energy mix within the next hundred years to come. While innovative emission reduction technologies are evolving for the better, trendy technological solutions which require reintegration of these coal plants with alternative greener fuels are growing at the moment. Among these solutions, the following paper investigates possible means for repowering a coal steam power plant with indirect solar heating solutions to boost its annual outputs. Two widely deployable solar thermal technologies, parabolic trough and Central tower receiver systems, are introduced at different locations in the steam plant to heat working fluid thereby enhancing the thermodynamic quality of steam being generated. Potential annual energy output was estimated using commercially available TRNSYS software upon mass and heat balance to every component of solar and steam plant. The annual energy outputs are weighed against their plant erecting and running costs to evaluate the economic vitality of the proposed repowering options. The results show that parabolic trough heating method could serve as the most cost effective method generating electricity at competitive prices than solar only powered SEGS plants. While cost may be acceptable in the unit of energy sense, the scale of implementation has been proven to be technically limited.
Kriel Power Plant

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Mohamed, Omar R. Ibrahim. "Study of energy efficient supercritical coal-fired power plant dynamic responses and control strategies." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3662/.

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The world is facing the challenge of global warming and environment protection. On the other hand, the demand of electricity is growing fast due to economic growth and increase in population. Since the growth in demand is also a heavy factor in energy equations, then the renewable energy alone is not able to generate enough electricity to fill the gap within a short time of period. Therefore, fossil fuel such as coal fired power plants cannot be ruled out immediately due to their generation capacity and flexibility in load following. However, any new coal fired stations should be cleaner compared with traditional power plants. Supercritical power plants are one of the most suitable choices for environmental enhancement and higher efficiency. However, there has been an issue of whether or not to adopt this technology in the UK because it is not clear whether the performance for SC plants can satisfy the British Gird Code requirement. This thesis reports a study of dynamic responses of SC power plants through mathematical modeling, and simulation for Gird Code compliance. It also presents a new control strategy based on an alternative configuration of generalized predictive control for power plant control.

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Zhao, Qiao. "Conception and optimization of supercritical CO2 Brayton cycles for coal-fired power plant application." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0080/document.

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L'amélioration des systèmes énergétiques est considérée comme un levier technologique pour répondre aux défis liés à la croissance de la demande d’électricité et des émissions des gaz à effet de serre. Les futures centrales devraient présenter une intégration thermique plus flexible et des sources de chaleur mixtes possibles. Une des solutions fiables consiste à utiliser un cycle de Brayton au CO2 supercritique (CO2-SC), un tel cycle à haut rendement est théoriquement prometteur pour les applications nucléaires, fossiles et solaires thermiques. Un des principaux obstacles au déploiement du cycle de Brayton au CO2-SC est de justifier sa faisabilité, sa viabilité et son potentiel à l’échelle industrielle. Dans ce contexte deux axes de recherche ont été identifiées : • Une sélection rigoureuse de l’équation d’état qui permet de représenter les propriétés d’intérêt du CO2-SC. • Une nouvelle méthodologie pour l’optimisation des centrales électriques, permettant de sélectionner automatiquement le procédé optimal parmi une grande quantité de configurations possibles (dénomme superstructure). Les résultats de la première partie de cette thèse mettent en lumière que l’équation de SW est pertinente pour limiter l’impact de l’imprécision de l’équation d’état sur le dimensionnement du procédé. Dans cette thèse, un simulateur de procédé commercial, ProSimPlus a été combiné avec un solveur type évolutionnaire (MIDACO) afin d’effectuer des optimisations superstructure. Premièrement, le critère d’optimisation est de maximiser le rendement énergétique du procédé. Dans un deuxième temps, on cherche simultanément à minimiser les coûts du procédé. Pour ce faire, des fonctions de coût internes à EDF ont été utilisées afin de permettre l’estimation des coûts d'investissement (CAPEX), des dépenses opérationnelles (OPEX) et du coût actualisé de l'électricité (LCOE)
Efficiency enhancement in power plant can be seen as a key lever in front of increasing energy demand. Nowadays, both the attention and the emphasis are directed to reliable alternatives, i.e., enhancing the energy conversion systems. The supercritical CO2 (SC-CO2) Brayton cycle has recently emerged as a promising solution for high efficiency power production in nuclear, fossil-thermal and solar-thermal applications. Currently, studies on such a thermodynamic power cycle are directed towards the demonstration of its reliability and viability before the possible building of an industrial-scale unit. The objectives of this PhD can be divided in two main parts: • A rigorous selection procedure of an equation of state (EoS) for SC-CO2 which permits to assess influences of thermodynamic model on the performance and design of a SC-CO2 Brayton cycle. • A framework of optimization-based synthesis of energy systems which enables optimizing both system structure and the process parameters. The performed investigations demonstrate that the Span-Wagner EoS is recommended for evaluating the performances of a SC-CO2 Brayton cycle in order to avoid inaccurate predictions in terms of equipment sizing and optimization. By combining a commercial process simulator and an evolutionary algorithm (MIDACO), this dissertation has identified a global feasible optimum design –or at least competitive solutions– for a given process superstructure under different industrial constraints. The carried out optimization firstly base on cycle energy aspects, but the decision making for practical systems necessitates techno-economic optimizations. The establishment of associated techno-economic cost functions in the last part of this dissertation enables to assess the levelized cost of electricity (LCOE). The carried out multi-objective optimization reflects the trade-off between economic and energy criteria, but also reveal the potential of this technology in economic performance

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Orlicka, Dominika. "Development of novel coatings to resist fireside corrosion in biomass-fired power plants." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/11825.

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The emission of CO2 to the atmosphere from firing conventional fossil fuels has become a major concern for the power industry, due to the enhanced greenhouse effect and global warming predictions. The increasing worldwide demand for electricity production is another issue. The replacement of fossil fuels with increasing quantities of biomass is of interest as biomass is considered to be carbon neutral and is widely distributed. Unfortunately, due to its composition, the risk of fireside corrosion found on heat exchangers (super- heaters and re-heaters) is greater than in coal-fired plants. Consequently, biomass-fired power plants operate at lower steam temperatures and pressures, leading to their poorer efficiency. Biomass-fired power plants suffer from alkali chloride-induced corrosion, considered faster and more severe than alkali sulphate-based corrosion common in traditional coal-fired plants. The main aim of this project was to develop a range of novel coating compositions which would be resistant to fireside corrosion found on boiler tubes in biomass-fired power plants. To accomplish this, studies were carried out into salt stabilities, coating oxidation and deposit corrosion. Salt stability experiments have resulted in improved understanding of the evaporation and sulphidation behaviour of KCl, NaCl, K2SO4 and Na2SO4 at high temperatures in environments containing HCl and SO2. KCl was chosen as a deposit for coating screening. Two-target magnetron co-sputtering was successfully used to deposit a range of coating compositions. These coatings were analysed at 550°C in corrosion environments containing combinations of HCl, KCl and water vapour. The addition of gaseous HCl did not have a significant influence on the coating degradation compared to similar tests in air. Deposited KCl significantly increased the corrosion rate, whereas adding 10% moisture to the environment with KCl had little additional effect. The growth of either protective Cr2O3 or less protective mixed oxides was observed on the different coating compositions. The best performing coatings had compositions in the range: 26.2 – 79.4 at% Cr, 12.1 – 62.9 at% Fe, 8.5 – 10.9 at% Al.

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Shomo, Laurie Suzanne 1951. "Biotic and physico-chemical conditions in a cooling reservoir of a coal-fired power plant." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277958.

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Cholla Lake is a cooling reservoir for the coal-fired Cholla electrical generating plant. The lake provides recreational fishing and water contact recreation. The fish populations are self-sustaining. I collected water, sediment, and whole body fish samples to be analyzed for levels of some possibly toxic inorganic constituents. I also measured dissolved oxygen, pH, Secchi disk transparency. I compared current fish population structure, fish stomach contents, and the frequency of occurrence of benthos, with those same parameters in previous studies. Water temperature and turbidity have increased; catfish and bluegill have increased in their relative abundance; and the density of benthic invertebrates has decreased. Aquatic insects occur most commonly in the stomach contents of bluegill and filamentous algae in the stomachs of catfish. Selenium levels in all matrices exceed national averages and are above levels in a nearby reservoir unaffected by the power station.

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Draganescu, Mihai. "Study of supercritical coal-fired power plant dynamic responses and control for grid code compliance." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/73963/.

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The thesis is concerned with the study of the dynamic responses of a supercritical coal-fired power plant via mathematical modelling and simulation. Supercritical technology leads to much more efficient energy conversion compared with subcritical power generation technology so it is considered to be a viable option from the economic and environmental aspects for replacement of aged thermal power plants in the United Kingdom. However there are concerns for the adoption of this technology as it is unclear whether the dynamic responses of supercritical power plants can meet the Great Britain Grid Code requirement in frequency responses and frequency control. To provide answers to the above concerns, the PhD research project is conducted with the following objectives: to study the dynamic responses of the power plant under different control modes in order to assess its compliance in providing the frequency control services specified by the Great Britain Grid Code; to evaluate and improve the performance of the existing control loops of the power plant simulator and in this regard a controller based on the Dynamic Matrix Control algorithm was designed to regulate the coal flow rate and another controller based on the Generalized Predictive Control algorithm was implemented to regulate the temperature of the superheated steam; to conduct an investigation regarding frequency control at the power plant level followed by an analysis of the frequency control requirements extracted from the Grid Codes of several European and non-European countries. The structure and operation of the supercritical power plant was intensively studied and presented. All the simulation tests presented in this thesis were carried out by the mean of a complex 600 megawatts power plant simulator developed in collaboration with Tsinghua University from Beijing, China. The study of the conducted simulation tests indicate that it is difficult for this type of power plant to comply with the frequency control requirements of the Great Britain Grid Code in its current control method. Therefore, it is essential to investigate more effective control strategies aiming at improving its dynamic responses. In the thesis, new Model Predictive Control power plant control strategies are developed and the performance of the control loops and consequently of the power plant are greatly improved through implementation of Model Predictive Control based controllers.

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Cheng, Lei. "CO2 Separation from Coal-Fired Power Plants by Regenerable Mg(OH)2 Solutions." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1378216250.

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Wang, Kelin. "Mercury Transportation in Soil Using Gypsum from Flue Gas Desulphurization Unit in Coal-Fired Power Plant." TopSCHOLAR®, 2012. http://digitalcommons.wku.edu/theses/1199.

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This work investigates mercury flux in soil amended by gypsum from flue gas desulphurization (FGD) units of coal-fired power plants. There are two phases of this research, including field and greenhouse studies. Previous studies indicate that FGD gypsum could increase corn yield, but may lead to more mercury uptake by corn. Recent studies have been carried out in greenhouses to investigate mercury transport in FGD gypsum treated soil. Major aspects include uptake of mercury by plants and emission of mercury into the atmosphere based on application rates of FGD gypsum. Additional aspects include rainfall, temperature, soil, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentration in the soil, as well as, increased mercury emission into the atmosphere, and increased mercury levels in plants, especially roots and leaves. Soil properties and plant species also played important roles in mercury transport. In addition, it was also found that increased water and higher temperatures may contribute to mercury emission in the atmosphere. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration within the soil. Mercury concentration in the stem of plants was found to be increased and then plateaued upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from mercury in the surrounding atmosphere.

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Bouzguenda, Mounir. "Study of the combined cycle power plant as a generation expansion alternative." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/101165.

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Analysis of future alternatives for US utilities is needed as a part of evaluating the impact of combined cycle and phased-construction of integrated coal gasifier power plants on generation expansion. The study encompassed both large and small electric utilities and long-run, least-cost expansion plan for the generating system and studies of the short-run production cost of electrical generation for selected years. The long-run studies were carried out using the Wien Automatic System Planning Package (WASP-II). The optimal combined cycle penetration level was determined for a set of assumptions that involve economics, new technology trends, and feasibility as well as the utility's existing capacity and load forecast. Additional cases were run to account for phased construction and coal gasification. Two electric utilities were selected in this study. These are a U.S. southeastern utility the Bangladesh Electric Utility. The former was chosen as the large utility. The latter was considered a small size utility. WASP-II enhancements enabled us to run cases using IBM-RT and to account for phased construction. The sensitivity studies involved the penetration levels, the fuel supply (oil and natural gas), and economic dispatch of coal gasifiers in particular, and combined cycle power plants in general. Load forecast, and availability of hydroelectric energy were kept uniform. However, adding new power plants and retiring old ones were considered to achieve a more economical and reliable planning strategy while considering issues of technical feasibility.
M.S.

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27

Le, Grange Willie. "Component development for a high fidelity transient simulation of a coal-fired power plant using Flownex SE." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29863.

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Large coal-fired power stations are designed to be run predominantly at full load and optimum conditions. The behaviour of plants, operating at low load and varying conditions, is getting more and more attention due to the introduction of variable renewable generation on the grid. Consequently, the need for a fully transient high-fidelity system based model has grown, as this will enable one to study the behaviour of plants under such non-ideal conditions. This report details the development of a feedwater heater, deaerator and turbine component for such a high-fidelity transient system model using the Flownex Simulation Environment, a onedimensional thermohydraulic network solver. The components have been modelled all with the aim of using minimal design input data. The feedwater heater component model includes transient effects and thermodynamic relations to represent aspects such as heater performance, level control and transient inertia. In determining the heat transfer characteristics, the model makes use of plant-performance data and correlates the amount of heat transfer by using the feedwater mass flow as the load indicating parameter. This approach eliminates the need for specific geometrical details to calculate the effective heat transfer area. The level control is modelled by using a level representation built from using heat exchanger design methods. The turbine component is modelled by using Fuls’ Semi-Ellipse law or the pressure drop modelling and Ray’s semi-empirical method for the efficiency modelling. The model also contains transient effects, which include thermal inertia due to the shaft and casing, and rotational inertia due to the shaft. The deaerator component is modelled by adapting the model presented by Banda, and modifying the model to work under various conditions. This involved using curve fit methods in Flownex to use input data to model the pressure drop over the main condensate valve. Each of the mentioned components was validated and verified with plant data and finally packaged into a compound component which is a component consisting of a subnetwork in Flownex. These compound components further contain design inputs which are easily accessible by the user. The component models were integrated into larger networks in which various scenarios can be run. A short transient scenario was run on the low-pressure feedwater train of a specific power station. The scenario involved a turbine trip where the bled steam valves for the heaters were closed suddenly. The speed of the valves closing was however unknown and after closing the valves in approximately 10 seconds, results agreed relatively well with plant data. This illustrated the short transient capabilities of the feedwater heater component model. The three component models (feedwater heater, turbine and deaerator) were finally integrated into a regenerative Rankine cycle and was set up using minimal design data. The boiler, condenser and condensate pump were set as boundary conditions in the network but all extraction points for the network were connected. Steady-state results were obtained for various load cases and the main temperature, flow and pressure results were compared. Results agree well with plant data, even at low load conditions

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Akpan, Patrick Udeme-Obong. "Impact on heat rate and subsequent emissions due to varying operation of coal fired power plants." Doctoral thesis, Faculty of Engineering and the Built Environment, 2019. https://hdl.handle.net/11427/31647.

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Energy mix modellers often use a constant emissions factor model, which more or less implies a constant heat rate, when trying to show the emissions reduction benefits of integrating renewable power generation system on the grid. This approach does not consider the fact that there is a deterioration in the heat rate with load for the Coal Fired Power Plants that need to accommodate the additional renewable supply. If varying heat rate were to be included in a study, it is often limited to plant specific cases. This PhD presents a novel Variable Turbine Cycle Heat Rate (V-TCHR) model for predicting the part load Turbine cycle heat rate (TCHR) response of various Coal Fired Power Plant (CFPP) architectures, without detail knowledge of the entire steam cycle parameters. A total of 192 process models of representative CFPP architectures were developed using a Virtual Plant software. The models had different combinations of the degree of reheat; the throttle temperature; throttle pressure; and condenser cooling technology. The part load response of all the models were simulated using the software.

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Alie, Colin F. "CO₂ capture with MEA integrating the absorption process and steam cycle of an existing coal-fired power plant /." Waterloo, Ont. : University of Waterloo, 2004. http://etd.uwaterloo.ca/etd/calie2004.pdf.

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Thesis (M.A.Sc.)--University of Waterloo, 2004.
Contains hypertext links. "A thesis presented to the University of Waterloo in fulfilment of the thesis requirement for the degree of Master of Applied Science in Chemical Engineering". Includes bibliographical references.

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Clay, Joshua Dewaine. "An Energetic and Exergetic Analysis of a Mid-Sized, Coal Fired Power Plant in the Midwestern United States." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2459.

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The focus of this project is the performance of an energy and exergy audit on a 173 MW pulverized coal fired, subcritical steam power plant unit in the Midwestern United States. Thermal efficiency is good for measuring the overall energy conversion capability of a process but it does not account for the entropy generation which occurs in real-world processes. This is where exergy analysis can be used to identify the greatest sources of loss due to the system’s irreversibilities, an unavoidable consequence of the second law of thermodynamics. The goal of this study is the calculation and mapping of energy and exergy cycle performance characteristics as well as the amounts of exergy destroyed throughout the process in the various components. With the magnitudes of the losses and their sources identified, mitigation options are compiled. The overall cycle energetic and exergetic efficiencies were found to be 32.8% and 33.7%, respectively. These values fall within the normal range expected for plants of this size and type. The largest source of exergy destruction in the cycle was found to be within the steam generator.

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Schneider, Helfried, Thomas Frank, Klaus Pachler, and Klaus Bernert. "A Numerical Study of the Gas-Particle Flow in Pipework and Flow Splitting Devices of Coal-Fired Power Plant." Universitätsbibliothek Chemnitz, 2002. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200200348.

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In power plants using large utility coal-fired boilers for generation of electricity the coal is pulverised in coal mills and then it has to be pneumatically transported and distributed to a larger number of burners (e.g. 30-40) circumferentially arranged in several rows around the burning chamber of the boiler. Besides the large pipework flow splitting devices are necessary for distribution of an equal amount of pulverised fuel (PF) to each of the burners. So called trifurcators (without inner fittings or guiding vanes) and ''riffle'' type bifurcators are commonly used to split the gas-coal particle flow into two or three pipes/channels with an equal amount of PF mass flow rate in each outflow cross section of the flow splitting device. These PF flow splitting devices are subject of a number of problems. First of all an uneven distribution of PF over the burners of a large utility boiler leads to operational and maintenance problems, increased level of unburned carbon and higher rates of NOX emissions. Maldistribution of fuel between burners caused by non uniform concentration of the PF (particle roping) in pipe and channel bends prior to flow splitting devices leads to uncontrolled differences in the fuel to air ratio between burners. This results in localised regions in the furnace which are fuel rich, where insufficient air causes incomplete combustion of the fuel. Other regions in the furnace become fuel lean, forming high local concentrations of NOX due to the high local concentrations of O2. Otherwise PF maldistribution can impact on power plant maintenance in terms of uneven wear on PF pipework, flow splitters as well as the effects on boiler panels (PF deposition, corrosion, slagging). In order to address these problems in establishing uniform PF distribution over the outlet cross sections of flow splitting devices in the pipework of coal-fired power plants the present paper deals with numerical prediction and analysis of the complex gas and coal particle (PF) flow through trifurcators and ''riffle'' type bifurcators. The numerical investigation is based on a 3-dimensional Eulerian- Lagrangian approach (MISTRAL/PartFlow-3D) developed by Frank et al. The numerical method is capable to predict isothermal, incompressible, steady gas- particle flows in 3-dimensional, geometrically complex flow geometries using boundary fitted, block-structured, numerical grids. Due to the very high numerical effort of the investigated gas-particle flows the numerical approach has been developed with special emphasis on efficient parallel computing on clusters of workstations or other high performance computing architectures. Besides the aerodynamically interaction between the carrier fluid phase and the PF particles the gas-particle flow is mainly influenced by particle-wall interactions with the outer wall boundaries and the inner fittings and guiding vanes of the investigated flow splitting devices. In order to allow accurate quantitative prediction of the motion of the disperse phase the numerical model requires detailed information about the particle-wall collision process. In commonly used physical models of the particle-wall interaction this is the knowledge or experimental prediction of the restitution coefficients (dynamic friction coefficient, coefficient of restitution) for the used combination of particle and wall material, e.g. PF particles on steel. In the present investigation these parameters of the particle-wall interaction model have been obtained from special experiments in two test facilities. Basic experiments to clarify the details of the particle-wall interaction process were made in a test facility with a spherical disk accelerator. This test facility furthermore provides the opportunity to investigate the bouncing process under normal pressure as well as under vacuum conditions, thus excluding aerodynamically influences on the motion of small particles in the near vicinity of solid wall surfaces (especially under small angles of attack). In this experiments spherical glass beads were used as particle material. In a second test facility we have investigated the real impact of non-spherical pulverised fuel particles on a steel/ceramic target. In this experiments PF particles were accelerated by an injector using inert gas like e.g. CO2 or N2 as the carrier phase in order to avoid dust explosion hazards. The obtained data for the particle-wall collision models were compared to those obtained for glass spheres, where bouncing models are proofed to be valid. Furthermore the second test facility was used to obtain particle erosion rates for PF particles on steel targets as a function of impact angles and velocities. The results of experimental investigations has been incorporated into the numerical model. Hereafter the numerical approach MISTRAL/PartFlow-3D has been applied to the PF flow through a ''riffle'' type bifurcator. Using ICEM/CFD-Hexa as grid generator a numerical mesh with approximately 4 million grid cells has been designed for approximation of the complex geometry of the flow splitting device with all its interior fittings and guiding vanes. Based on a predicted gas flow field a large number of PF particles are tracked throughout the flow geometry of the flow-splitter. Besides mean quantities of the particle flow field like e.g. local particle concentrations, mean particle velocities, distribution of mean particle diameter, etc. it is now possible to obtain information about particle erosion on riffle plates and guiding vanes of the flow splitting device. Furthermore the influence of different roping patterns in front of the flow splitter on the uniformness of PF mass flow rate splitting after the bifurcator has been investigated numerically. Results show the efficient operation of the investigated bifurcator in absence of particle roping, this means under conditions of an uniform PF particle concentration distribution in the inflow cross section of the bifurcator. If particle roping occurs and particle concentration differs over the pipe cross section in front of the bifurcator the equal PF particle mass flow rate splitting can be strongly deteriorated in dependence on the location and intensity of the particle rope or particle concentration irregularities. The presented results show the importance of further development of efficient rope splitting devices for applications in coal-fired power plants. Numerical analysis can be used as an efficient tool for their investigation and further optimisation under various operating and flow conditions.

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Hutchens, Steven Jason. "Modeled sulfur dioxide exposure from a proposed coal fired power plant, using geographic information systems and air dispersion modeling." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3376.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains xii, 161 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 132-137).

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Li, Fei. "Modelling and optimisation of post-combustion carbon capture process integrated with coal-fired power plant using computational intelligence techniques." Thesis, University of Newcastle upon Tyne, 2018. http://hdl.handle.net/10443/4013.

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Coal-fired power plants are the major source of CO2 emission which contributes significantly to global climate change. An effective way to reduce CO2 emission in coal-fired power plants is post-combustion carbon dioxide (CO2) capture (PCC) with chemical absorption. The aim of this project is to carry out some research in model development, process analysis, controller design and process optimization for reliable, optimal design and control of coal-fired supercritical power plant integrated with post-combustion carbon capture plant. In this thesis, three different advanced neural network models are developed: bootstrap aggregated neural networks (BANNs) model, bootstrap aggregated extreme learning machine (BAELM) model and deep belief networks (DBN) model. The bootstrap aggregated model can offer more accurate predictions than a single neural network, as well as provide model prediction confidence bounds. However, both BANNs and BAELM have a shallow architecture, which is limited to represent complex, highly-varying relationship and easy to converge to local optima. To resolve the problem, the DBN model is proposed. The unsupervised training procedure is helpful to get the optimal solution of supervised training. The purpose of developing neural network models is to find a best model which can be used in the optimization of the CO2 capture process precisely. This thesis also presents a comparison of centralized and decentralized control structures for post-combustion CO2 capture plant with chemical absorption. As for centralized configuration, a dynamic multivariate model predictive control (MPC) technique is used to control the post-combustion CO2 capture plant attached to a coal-fired power plant. When consider the decentralized control structures based on multi-loop proportional-integral-derivative (PID) controllers, two different control schemes are designed using relative disturbance gain (RDG) analysis and dynamic relative gain array (DRGA) analysis, respectively. By comparing the two control structures, the MPC structure performs better in terms of closed-loop settling time, integral squared error, and disturbance injection.

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Khobo, Rendani Yaw-Boateng Sean. "A modelling methodology to quantify the impact of plant anomalies on ID fan capacity in coal fired power plants." Master's thesis, Faculty of Engineering and the Built Environment, 2020. http://hdl.handle.net/11427/32244.

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In South Africa, nearly 80 % of electricity is generated from coal fired power plants. Due to the complexity of the interconnected systems that make up a typical power plant, analysis of the root causes of load losses is not a straightforward process. This often leads to losses incorrectly being ascribed to the Induced Draught (ID) fan, where detection occurs, while the problem actually originates elsewhere in the plant. The focus of this study was to develop and demonstrate a modelling methodology to quantify the effects of major plant anomalies on the capacity of ID fans in coal fired power plants. The ensuing model calculates the operating point of the ID fan that is a result of anomalies experienced elsewhere in the plant. This model can be applied in conjunction with performance test data as part of a root cause analysis procedure. The model has three main sections that are integrated to determine the ID fan operating point. The first section is a water/steam cycle model that was pre-configured in VirtualPlantTM. The steam plant model was verified via energy balance calculations and validated against original heat balance diagrams. The second is a draught group model developed using FlownexSETM. This onedimensional network is a simplification of the flue gas side of the five main draught group components, from the furnace inlet to the chimney exit, characterising only the aggregate heat transfer and pressure loss in the system. The designated ID fan model is based on the original fan performance curves. The third section is a Boiler Mass and Energy Balance (BMEB) specifically created for this purpose to: (1) translate the VirtualPlant results for the steam cycle into applicable boundary conditions for the Flownex draught group model; and (2) to calculate the fluid properties applicable to the draught group based on the coal characteristics and combustion process. The integrated modelling methodology was applied to a 600 MW class coal fired power plant to investigate the impact of six major anomalies that are typically encountered. These are: changes in coal quality; increased boiler flue gas exit temperatures; air ingress into the boiler; air heater inleakage to the flue gas stream; feed water heaters out-of-service; and condenser backpressure degradation. It was inter alia found that a low calorific value (CV) coal of 14 MJ/kg compared to a typical 17 MJ/kg reduced the fan's capacity by 2.1 %. Also, having both HP FWH out of service decreased the fan's capacity by 16.2 %.

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Basson, Nicol. "Studying water-wedging as a cause for short term overheating in the boiler of a coal-fired power plant." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29585.

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A common failure occurrence on fossil fuel power plant boiler systems is referred to as short term overheating (STO). This phenomenon occurs when the tube is heated to higher than its design temperature in a short period of time, causing a ductile failure of the tube material. The superheaters are particularly susceptible to STO. Such a failure can be caused by various conditions, where most of these are condition-based, i.e. based on the physical condition of the pipes or boiler. However, there are some cases which are process-related, i.e. based on the thermo-physical process occurring inside the pipe. Very often a water blockage or water wedge is recorded to be the root cause of the short term overheating in superheaters when no condition-based indicators can be found. It then is claimed to be the result of over-attemperation spray by the operator. This type of failure tends to happen at the outlet of vertical (pendant-type) superheaters. This study aims to find thermo-physical conditions where such a conclusion is valid by studying the transient behaviour of a representative superheater segment under postulated conditions. The specific geometry chosen is one for which short term overheating due to water wedging has been recorded in the past. A transient flow model was constructed and verified by comparing its results with plant data, as well as some results from a numerical model developed from fundamental principles. Once the simulation modelling methodology was confirmed, the model was modified to resemble the geometry of the final superheater outlet leg to facilitate direct comparison with a pendant boiler component as found on a power plant. A number of scenarios were executed in transient state on the model at different boiler loads. The temperature evolution of the pipe wall was tracked over time, and together with calculated equivalent stresses, was compared to the yield strength of the material. A temperature vs yield strength curve was obtained from material testing using new and aged tube material. The results showed that short term overheating at the superheater outlet tubes due to water blockages alone is unlikely to occur, even at low loads and substantial over firing. The stresses exerted over the tube wall and throughout the tube length is not enough to overcome the yield stress of the superheater tube material, even for aged material. Thus, the claim of overattemperation as the root cause of a short term overheating failure is improbable, and other explanations for the failure must be observed. Even though it is possible for water-wedging to occur, the phenomenon alone is unlikely to be the root cause for the occurrence of short term overheating.

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BARUA, SUKHENDU LAL. "APPLICATION OF CONDITIONAL SIMULATION MODEL TO RUN-OF-MINE COAL SAMPLING FREQUENCY DETERMINATION AND COAL QUALITY CONTROL AT THE POWER PLANT (BLENDING, GOAL PROGRAMMING, MICROCOMPUTER)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/187940.

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Run-of-mine (ROM) coal sampling is one of the most important factors in determining the disposition of ROM coal for an overall emission control strategy. Determination of the amount of sample, or still better, the frequency of ROM coal sampling is thus essential to the analysis of overall emission control strategies. A simulation model of a portion of the Upper Freeport coal seam in western Pennsylvania was developed employing conditional simulation. On the simulated deposit, different mining methods were simulated to generate ROM coal data. ROM coal data was statistically analyzed to determine the sampling frequency. Two schemes were suggested: (1) the use of geostatistical techniques if there is spatial correlation in ROM coal quality, and (2) the use of classical statistics if the spatial correlation in ROM coal quality is not present. Conditions under which spatial correlation in ROM coal quality can be expected are also examined. To link the ROM coal and coals from other sources to coal stockpiles and subsequently to solve coal blending problems, where varying qualities of stockpiled coals are normally used, an interactive computer program was developed. Simple file-handling, for stockpiling problems, and multi-objective goal programming technique, for blending problems, provided their solutions. The computer program was made suitable for use on both minicomputer and microcomputer. Menu-driven and interactive capabilities give this program a high level of flexibility that is needed to analyze and solve stockpiling and blending problems at the power plant.

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37

Alie, Colin. "CO₂ Capture With MEA: Integrating the Absorption Process and Steam Cycle of an Existing Coal-Fired Power Plant." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/796.

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In Canada, coal-fired power plants are the largest anthropogenic point sources of atmospheric CO₂. The most promising near-term strategy for mitigating CO₂ emissions from these facilities is the post-combustion capture of CO₂ using MEA (monoethanolamine) with subsequent geologic sequestration. While MEA absorption of CO₂ from coal-derived flue gases on the scale proposed above is technologically feasible, MEA absorption is an energy intensive process and especially requires large quantities of low-pressure steam. It is the magnitude of the cost of providing this supplemental energy that is currently inhibiting the deployment of CO₂ capture with MEA absorption as means of combatting global warming. The steam cycle of a power plant ejects large quantities of low-quality heat to the surroundings. Traditionally, this waste has had no economic value. However, at different times and in different places, it has been recognized that the diversion of lower quality streams could be beneficial, for example, as an energy carrier for district heating systems. In a similar vein, using the waste heat from the power plant steam cycle to satisfy the heat requirements of a proposed CO₂ capture plant would reduce the required outlay for supplemental utilities; the economic barrier to MEA absorption could be removed. In this thesis, state-of-the-art process simulation tools are used to model coal combustion, steam cycle, and MEA absorption processes. These disparate models are then combined to create a model of a coal-fired power plant with integrated CO₂ capture. A sensitivity analysis on the integrated model is performed to ascertain the process variables which most strongly influence the CO₂ energy penalty. From the simulation results with this integrated model, it is clear that there is a substantial thermodynamic advantage to diverting low-pressure steam from the steam cycle for use in the CO₂ capture plant. During the course of the investigation, methodologies for using Aspen Plus® to predict column pressure profiles and for converging the MEA absorption process flowsheet were developed and are herein presented.

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38

Sansayavichai, Pathratipa. "An approach designed for regional prospective human health and ecological risk assessment and its application to mercury risks from a coal-fired power plant." Connect to this title online, 2009.

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39

Olaleye, Akeem Kehinde. "Modelling and operational analysis of coal-fired supercritical power plant integrated with post-combustion carbon capture based on chemical absorption under UK grid requirement." Thesis, University of Hull, 2015. http://hydra.hull.ac.uk/resources/hull:13227.

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Fossil-fuel fired power plants are subjected to stringent operational regime due to the influx of renewable resources and the CO2 emission reduction target. This study is aimed at modelling and analysis of supercritical coal-fired power plant (SCPP) integrated with post-combustion CO2 capture (PCC) and its response electricity grid demand constraints. Current status of dynamic modelling of SCPP integrated with PCC was reviewed to identify the gaps in knowledge. It was observed that no accurate dynamic model of an SCPP integrated with PCC had been reported in open literature. A steady state model of the SCPP integrated with PCC was developed with Aspen Plus®. The model was validated with the reference plant and it was found that the relative error is about 1.6%. The results of the conventional and advanced exergetic analysis showed that the energy/exergy consumption and the efficiency of the integrated system can be improved by recovering the avoidable exergy destruction in the whole system. Dynamic models of SCPP once-through boiler based on lumped parameter and distributed parameter approaches were compared. The distributed parameter model gave a more accurate prediction of the SCPP boiler dynamics at different load levels. Analysis of the strategies for operating the SCPP under the UK grid requirement as regards to primary frequency response was performed using the validated SCPP model. The results show that using turbine throttling approach, extraction stop or condensate stop individually was not sufficient to meet the grid requirement. A combination of turbine throttling, extraction stop and/or condensate stop can achieve a 10% increase in maximum continuous rating (MCR) of the power plant within 10 seconds to 30 seconds of primary frequency change as required by the UK grid. The dynamic model of SCPP was integrated with a validated and scaled-up model of PCC. Analysis of the strategies for operating the SCPP integrated with PCC under the UK grid requirement as regards to primary frequency response was undertaken. The results show that the stripper stop mechanism is not sufficient for the 10% MCR required for the primary response. The results show that the combination of stripper stop mechanism with extraction stop can meet the 10% MCR requirement for integrated plant operating at above 75% of its full capacity. The throttling and stripper stop configuration only barely meets the demand at full load capacity. The condensate stop combination with the stripper stop mechanism on the other hand could not meet the frequency response requirement at any load level.

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40

Prinsloo, Gerto. "Online boiler convective heat exchanger monitoring: a comparison of soft sensing and data-driven approaches." Master's thesis, Faculty of Engineering and the Built Environment, 2018. http://hdl.handle.net/11427/30038.

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Online monitoring supports plant reliability and performance management by providing real time information about the condition of equipment. However, the intricate geometries and harsh operating environment of coal fired power plant boilers inhibit the ability to do online measurements of all process related variables. A low-cost alternative lies in the possibility of using knowledge about boiler operation to extract information about its condition from standard online process measurements. This approach is evaluated with the aim of enhancing online condition monitoring of a boiler’s convective pass heat exchanger network by respectively using a soft sensor and a data-driven method. The soft sensor approach is based on a one-dimensional thermofluid process model which takes measurements as inputs and calculates unmeasured variables as outputs. The model is calibrated based on design information. The data-driven method is one developed specifically in this study to identify unique fault signatures in measurement data to detect and quantify changes in unmeasured variables. The fault signatures are initially constructed using the calibrated one-dimensional thermofluid process model. The benefits and limitations of these methods are compared at the hand of a case study boiler. The case study boiler has five convective heat exchanger stages, each composed of four separate legs. The data-driven method estimates the average conduction thermal resistance of individual heat exchanger legs and the flue gas temperature at the inlet to the convective pass. In addition to this, the soft sensor estimates the average fluid variables for individual legs throughout the convective pass and therefore provides information better suited for condition prognosis. The methods are tested using real plant measurements recorded during a period which contained load changes and on-load heat exchanger cleaning events. The cleaning event provides some basis for validating the results because the qualitative changes of some unmeasured monitored variables expected during this event are known. The relative changes detected by both methods are closely correlated. The data-driven method is computationally less expensive and easily implementable across different software platforms once the fault signatures have been obtained. Fault signatures are easily trainable once the model has been developed. The soft sensors require the continuous use of the modelling software and will therefore be subject to licencing constraints. Both methods offer the possibility to enhance the monitoring resolution of modern boilers without the need to install any additional measurements. Implementation of these monitoring frameworks can provide a simple and low-cost contribution to optimized boiler performance and reliability management.

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Krydl, Ondřej. "Uhelné elektrárny: levná elektřina vs. čisté životní prostředí." Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-264667.

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The aim of this thesis is to analyze the importance of coal-fired power plants on the market of electric energy, with emphasis on aspects that fundamentally affect their production. Coal-fired power plants belongs nowadays among socially unpopular source of electricity. In recent decades intensively growing interest groups that support state intervention and regulation of the energy sector. This is essentially a massive promotion of renewable energy sources at the expense of fossil fuel plants. Analysis of individual power sources shows that despite the current restrictive measures imposed on power plants burning fossil fuels, and especially coal-fired power plants, electricity produced from coal resources is still competitive, despite some drawbacks has many positive qualities. Coal-fired power plants produce higher amounts of greenhouse gases and other pollutants than other types of power plants. On the other hand, they are able to provide a stable supply of electricity to transmission network, and thus partially offset the high volatility of electricity supply from renewable energy sources. The price of electricity from coal-fired power plants could be considered as relatively low in comparison with other energy sources. The analysis shows that in terms of practical economic policy is not economically justified to reduce the proportion of coal-fired power plants in the total production of electricity.

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Fahrni, Jason K. "Assessment of the Severity, Sources, and Meteorological Transport of Ambient and Wet Deposited Mercury in the Ohio River Valley Airshed." Ohio University / OhioLINK, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1125427320.

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Stephan, Christopher C. "Investigation of Air Moisture Quality in the Ohio River Valley." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416906418.

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44

Ebune, Guilbert Ebune. "Carbon Dioxide Capture from Power Plant Flue Gas using Regenerable Activated Carbon Powder Impregnated with Potassium Carbonate." Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1221227267.

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45

Zhang, Wei, Genchong Zhen, Long Chen, et al. "Benefits of Mercury Controls for China and the Neighboring Countries in East Asia." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/15.

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Exposure to mercury poses significant risks to the health of humans and wildlife. Globally, coal-fired power plant (CFPP) is a major source of mercury emissions, with China being the largest contributor to global atmospheric mercury. As a signatory country of the Minamata Convention on Mercury, China is developing its National Implementation Plan on Mercury Control, which gives priority to control of mercury emissions from CFPPs. While social benefits play an important role in designing environmental policies in China, the potential public health and economic benefits of mercury control in the nation are not yet understood, mainly due to the scientific challenges to trace mercury’s emissions-to-impacts path. Moreover, little is known about the potential benefits for the neighboring countries in East Asia resulted from China’s mercury control. This study evaluates the health and economic benefits for China and neighboring countries in East Asia from mercury reductions from China’s CFPPs. Four representative mercury control policy scenarios are analyzed, and the evaluation is explicitly conducted following the policies-to-impacts path under each policy scenario. We link a global atmospheric model to health impact assessment and economic valuation models to estimate economic gains for China and its three neighboring countries (Japan, South Korea and North Korea) from avoided mercury-related adverse health outcomes under the four emission control scenarios, and also take into account the key uncertainties in the policies-to-impacts path. Under the most stringent control scenario, the cumulative benefit of the mercury reduction by 2030 is projected to be $430 billion for the four countries together (the 95% confidence interval is $102-903 billion, in 2010 USD). Our findings suggest that although China is the biggest beneficiary of the mercury reduction in CFPPs, neighboring countries including Japan, South Korea and North Korea can also benefit (~7% of the total benefits) from China’s mercury reduction.

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JHONG, CHENG-EN, and 鍾承恩. "Benefit Assessment of Converted Biomass Energy Palm-fired Power Generation in Coal-fired Thermal Power Plants in Mailiao." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/daeged.

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碩士
國立雲林科技大學
電機工程系
107
In recent years, due to the crisis of power supply in our country, considering the factors such as greenhouse gases and air pollution, the industry and academia have been making a lot of comments and research on this topic. The more common issues at present are the pro-nuclear, the conversion of power plants to gas units and the restart of the ShenAo Thermal Power Plant. However, due to the unresolved EIA, the high cost of investment and time, it is imperative for the current situation. Therefore, the thesis proposes puts forward different views for the problems. Based on the average cost computation proposed by the IEA, we use the MaiLiao Thermal Power Plant as an example. Cost-effectiveness and carbon emission cost of palm kernel shells power generation are calculated, and the combustion emissions are evaluated. Compared with burning coal (hard coal), the use of palm kernel shells as the fuel for power plants not only generates lower power generation costs, but also reduces the cost and time of thermal power plant transformation, and provides another method.

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47

Gomez, Patsky O. "Development of a Low NOx Burner System for Coal Fired Power Plants Using Coal and Biomass Blends." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-651.

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The low NOx burner (LNB) is the most cost effective technology used in coal-fired power plants to reduce NOx. Conventional (unstaged) burners use primary air for transporting particles and swirling secondary air to create recirculation of hot gases. LNB uses staged air (dividing total air into primary, secondary and tertiary air) to control fuel bound nitrogen from mixing early and oxidizing to NOx; it can also limit thermal NOx by reducing peak flame temperatures. Previous research at Texas A&M University (TAMU) demonstrated that cofiring coal with feedlot biomass (FB) in conventional burners produced lower or similar levels of NOx but increased CO. The present research deals with i) construction of a small scale 29.31 kW (100,000 BTU/hr) LNB facility, ii) evaluation of firing Wyoming (WYO) coal as the base case coal and cofiring WYO and dairy biomass (DB) blends, and iii) evaluating the effects of staging on NOx and CO. Ultimate and Proximate analysis revealed that WYO and low ash, partially composted, dairy biomass (LA-PC-DB-SepS) had the following heat values and empirical formulas: CH0.6992N0.0122O0.1822S0.00217 and CH_1.2554N_0.0470O_0.3965S_0.00457. The WYO contained 3.10 kg of Ash/GJ, 15.66 kg of VM/GJ, 0.36 kg of N/GJ, and 6.21 kg of O/GJ while LA-PC-DB-SepS contained 11.57 kg of Ash/GJ, 36.50 kg of VM/GJ, 1.50 kg of N/GJ, and 14.48 kg of O/GJ. The construction of a LNB nozzle capable of providing primary, swirled secondary and swirled tertiary air for staging was completed. The reactor provides a maximum residence time of 1.8 seconds under hot flow conditions. WYO and DB were blended on a mass basis for the following blends: 95:5, 90:10, 85:15, and 80:20. Results from firing pure WYO showed that air staging caused a slight decrease of NOx in lean regions (equivalence ratio, greater than or equal to 1.0) but an increase of CO in rich regions (=1.2). For unstaged combustion, cofiring resulted in most fuel blends showing similar NOx emissions to WYO. Staged cofiring resulted in a 12% NOx increase in rich regions while producing similar to slightly lower amounts of NOx in lean regions. One conclusion is that there exists a strong inverse relationship between NOx and CO emissions.

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Carlin, Nicholas T. "Optimum usage and economic feasibility of animal manure-based biomass in combustion systems." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-759.

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Manure-based biomass (MBB) has the potential to be a source of green energy at large coal-fired power plants and on smaller-scale combustion systems at or near confined animal feeding operations. Although MBB is a low quality fuel with an inferior heat value compared to coal and other fossil fuels, the concentration of it at large animal feeding operations can make it a viable source of fuel. Mathematical models were developed to portray the economics of co-firing and reburning coal with MBB. A base case run of the co-fire model in which a 95:5 blend of coal to low-ash MBB was burned at an existing 300-MWe coal-fired power plant was found to have an overall net present cost of $22.6 million. The most significant cost that hindered the profitability of the co-fire project was the cost of operating gas boilers for biomass dryers that were required to reduce the MBB's moisture content before transportation and combustion. However, a higher dollar value on avoided nonrenewable CO2 emissions could overrule exorbitant costs of drying and transporting the MBB to power plants. A CO2 value of $17/metric ton was found to be enough for the MBB co-fire project to reach an economic break-even point. Reburning coal with MBB to reduce NOx emissions can theoretically be more profitable than a co-fire project, due to the value of avoided NOx emissions. However, the issue of finding enough suitable low-ash biomass becomes problematic for reburn systems since the reburn fuel must supply 10 to 25% of the power plant?s heat rate in order to achieve the desired NOx level. A NOx emission value over $2500/metric ton would justify installing a MBB reburn system. A base case run of a mathematical model describing a small-scale, on-the-farm MBB combustion system that can completely incinerate high-moisture (over 90%) manure biomass was developed and completed. If all of the energy or steam produced by the MBB combustion system were to bring revenue to the animal feeding operation either by avoided fueling costs or by sales, the conceptualized MBB combustion system has the potential to be a profitable venture.

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Ming-ChouTsai and 蔡銘洲. "Optimization Matching Analysis for Coal-fired Power Plant." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/72607197342122093457.

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碩士
國立成功大學
工學院工程管理專班
98
As it is well known, traditional fire power plants are coal-fired. The exhaust gas, however, contains substances such as fly ash, sulfur oxide, nitrogen oxide and carbon dioxide, which worsen the environment and global warming. Unfortunately, there is no single type of coal that can be used to generate electricity with regard to the environmental protection. Apart from that, the quality of coal has a tremendous influence on the operation of the boiler. As a result, it requires a circumspect investigation and evaluation to select and matching the coal. Since various characteristics of the coal will decrease boiler efficiency and exceed the limit set by the environmental protection policy, the cost will consequently increase.To learn to lower the cost, the study investigates the conditions of the equipment in power plants and the data of burning coal. Then, it analyses both the relationship between the coal quality and the materials concerned, and the operation cost that is affected. Using the Linear Programming Model, this study obtains the optimization matching formula of coal with the minimum price and the range of price changes. This case study indicates that, by setting up the Linear Programming Model,the optimization matching formula can be obtained despite various limitations. Since the material purchasing, coal price, coal amount,payment and the emissions of air pollutants can be estimated in advance, it helps the power plant to set up the annual budget, including material purchasing and sales amount, and therefore to improve the overall operational performance. In addition, Situational Analysis can help power plants to increase the accuracy of investment analysis as they try to ameliorate the equipments or expand the power plant.

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Chen, Meng-Kan, and 陳孟甘. "Constituents of Coal-Fired Power Plant Flue Gas Characteristic." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/93095442900315862311.

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碩士
崑山科技大學
環境工程研究所
101
Taiwan has more than 60% areas dependent on the coal-fired power generation, will produce air pollutants of combustion process and cause the destruction of the environment and the ecosystem, constitutes a serious threat to human health and animal and plant. Through the analysis of exhaust gas composition, to understand the characteristic of the emitted pollutants and their precursor substances, advanced air pollution prevention and control for the coal-fired power generation in the future. Coal main components for carbon, hydrogen, oxygen few of nitrogen, sulfur and other element, sulfur is coal most main impurities one of, usually to sulphides of forms appeared coal of combustion generated material in this research for domestic a coal-fired power plant of smoke road wall crystals, stack flue and smoke flow gas for sampling analysis; crystal detection results found main anionic ingredients for F-, and Cl- and the SO42-; cationic part is to NH4+ and Na+. Testing basic Physical chemistry stack flue exhaust composition differences, dry exhaust average exhaust flow, flow rate, temperature, oxygen, water, carbon dioxide, carbon monoxide and other projects, in different units moving emissions stable. Exhaust emissions of NH3 in the composition and H2SO4 to pipe gas main ingredient, and crystallization of particulate anion and caution SO42-, NH4+ primary characteristic ingredients of consistent results.

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Dissertations / Theses on the topic 'Coal-fired power plant; biomass'

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