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Dissertations / Theses on the topic 'Waste combustion'
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1
Kusar, Henrik. "Catalytic combustion of gasified waste." Doctoral thesis, KTH, Chemical Engineering and Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3600.
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<p>This thesis concerns catalytic combustion for gas turbineapplication using a low heating-value (LHV) gas, derived fromgasified waste. The main research in catalytic combustionfocuses on methane as fuel, but an increasing interest isdirected towards catalytic combustion of LHV fuels. This thesisshows that it is possible to catalytically combust a LHV gasand to oxidize fuel-bound nitrogen (NH3) directly into N2without forming NOX. The first part of the thesis gives abackground to the system. It defines waste, shortly describesgasification and more thoroughly catalytic combustion.</p><p>The second part of the present thesis, paper I, concerns thedevelopment and testing of potential catalysts for catalyticcombustion of LHV gases. The objective of this work was toinvestigate the possibility to use a stable metal oxide insteadof noble metals as ignition catalyst and at the same timereduce the formation of NOX. In paper II pilot-scale tests werecarried out to prove the potential of catalytic combustionusing real gasified waste and to compare with the resultsobtained in laboratory scale using a synthetic gas simulatinggasified waste. In paper III, selective catalytic oxidation fordecreasing the NOX formation from fuel-bound nitrogen wasexamined using two different approaches: fuel-lean andfuel-rich conditions.</p><p>Finally, the last part of the thesis deals with deactivationof catalysts. The various deactivation processes which mayaffect high-temperature catalytic combustion are reviewed inpaper IV. In paper V the poisoning effect of low amounts ofsulfur was studied; various metal oxides as well as supportedpalladium and platinum catalysts were used as catalysts forcombustion of a synthetic gas.</p><p>In conclusion, with the results obtained in this thesis itwould be possible to compose a working catalytic system for gasturbine application using a LHV gas.</p><p><b>Keywords:</b>Catalytic combustion; Gasified waste; LHVfuel; RDF; Biomass; Selective catalytic oxidation; NH3; NOX;Palladium; Platinum; Hexaaluminate; Garnet; Spinel;Deactivation; Sulfur; Poisoning</p>
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Sørum, Lars. "Environmental aspects of municipal solid waste combustion." Doctoral thesis, Norwegian University of Science and Technology, Norwegian University of Science and Technology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1488.
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Gopalakrishnan, Priya. "Effects of the reacting flowfield on combustion processes in a stagnation point reverse flow combustor." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22682.
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Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008.<br>Committee Chair: Seitzman, Jerry; Committee Member: Gaeta, Richard; Committee Member: Jagoda, Jeff; Committee Member: Neumeier, Yedidia; Committee Member: Yoda, Minami; Committee Member: Zinn, Ben.
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Kan, Tie. "Combustion of solid waste in a pulse incinerator." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/12975.
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Ou, Jenq-Jang. "The combustion of fossil and waste solid fuels." Thesis, Imperial College London, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308074.
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Laryea-Goldsmith, Rene. "Concurrent combustion of biomass and municipal solid waste." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/5580.
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This PhD research project is primarily an investigation of the gaseous pollutant emissions arising from concurrent combustion of biomass and municipal solid wastes materials, using a fluidized bed combustor. Of the wide range of biomass energy resources available, dried distillers’ grains with solubles and wheat straw were chosen as two example agricultural by-products of the human food supply chain. To consider an integrated waste management programme, a residual waste resource from a materials recycling facility was identified as a waste materials source that could be utilized after materials recycling was performed (which is a higher priority activity with respect to energy recovery). Cont/d.
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Kleiss, Torsten. "Institutional arrangements for municipal solid waste combustion projects." Weimar Bauhaus-Univ, 2008. http://d-nb.info/992651913/04.
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Moradian, Farzad. "Co-Combustion of Municipal Solid Waste and Animal Waste : Experiment and Simulation Studies." Licentiate thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3679.
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Co-combustion of animal carcasses and slaughterhouse waste products (animal waste), which are classed as high-risk infectious waste, has been considered as a “fuel opportunity” for waste-to-energy boilers. In this study, the impact of co-combustion of animal waste with municipal solid waste (MSW) on operational issues such as bed agglomeration, deposit formation and emission was investigated, employing experimental and theoretical methods. In the experimental section, a series of full-scale tests in a bubbling fluidised-bed boiler were carried out, to determine the effects of animal waste co-combustion on the issues addressed. Two combustion scenarios were considered, identified as the reference (Ref) case and the animal waste (AW) case. In the Ref case, a solid-waste fuel mix, consisting of sorted and pretreated industry and household waste was combusted. In the AW case, 20 wt% AW was added to the reference fuel mix. The collected samples, which included super-heater deposits, fuel mixes and bed and fly ashes, were analysed, using chemical fractionation, SEM-EDX and XRD. In addition, the flue gases´ emission rate were continuously analysed, using FTIR spectrometry. The results showed positive effects from co-combustion of AW, indicating decreased deposit formation and lower risk of bed agglomeration, as well as reduced emissions of NOx and SO2. Moreover, it was found that the concentrations of P, Ca, S and Cl were enriched in the bed materials. In the theoretical section, thermodynamic calculations, with respect to experimental data, were performed to provide greater understanding of the ash transformation behaviour and the related melting temperature. The calculations mainly focused on bed agglomeration, where addition of AW to the MSW considerably reduced the risk of agglomeration. The results of equilibrium products and phase diagram information for the bed ashes suggested melt-induced agglomeration as a possible cause of the formation of sticky layers on the bed particle in the Ref case. Moreover, it was concluded that higher amounts of calcium phosphate and sulfates increased the first melting temperature of the bed ashes in the AW case.<br><p><strong>Sponsorship</strong>:</p><p>Waste Refinery and Sparbanksstiftelsen Sjuhärad</p>
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Eriksson, L. Gunnar. "Combustion of solid waste from wood-based ethanol production /." Luleå, 2005. http://epubl.luth.se/1402-1757/2005/22.
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Gudim, Simen Johan. "Haraldrud Municipal Solid Waste Combustion Plant in Oslo : Optimizing, Stabilizing and Modeling the Combustion Process." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13233.
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This thesis has studied Haraldrud MSW combustion process. Haraldrud is a realcombustion plant burning waste for citizens of Oslo. A thoroughly description ofthe combustion process has been presented based on manipulating and analyzing theprocess, together with long discussions with the plant engineers. Working with a realplant is time-consuming, challenging and very informative. Rarely theories are easyto implement on a real plant, and the focus of this thesis has been to connect theoryand practice. All simulations are based on real process data.Burning MSW is a complex process to control, and several factors including;unknown calorific value, regulation of the waste flow, and the long time constant formeasuring and regulating the energy contributes to this. Todays unknown calorificvalue and measuring the energy from the combustion can be calculated from flue gasmeasurements. By implementing these in a new controller at Haraldrud the variationin energy from the combustion will be reduced and results in waste flow increase.One method to develop a model and estimate the model parameters is to decide amodel set and estimate the model parameters based on system identification theory.An open-loop system identification test was applied to the combustion process. Further,the model parameters to a MIMO ARX model were estimated from recordedtest data. It was concluded that the process variation in the gathered open-loopdata was too large, which resulted in a poor model. The model should instead beestimated based on closed-loop identification.Another method to estimate the model parameters is to use a control law toestimate the parameters on-line. Gradient method is one control law and has beenvalidated from recorded process data. The simulation shows that the estimated andmeasured outputs followed each other perfectly.
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Arunajatesan, Srinivasan. "Numerical modeling of waste incineration in dump combustors." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/12332.
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Roberts, Warren B. "Black liquor droplet combustion and modeling /." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1339.pdf.
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Lee, Tai-Gyu. "Modeling of hazardous waste incinerator : failure diagnostic and staged combustion." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/35447.
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Shui, Siyuan. "Pyrolysis of medical waste and the pyro gas combustion system." Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204873.
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This report reviews the different types of medical waste and associated medical waste generation data by geographic regions. Incineration methods and non-incineration methods, together with their associated technologies, are reviewed in detail. Among all the methods, pyrolysis technologies are, in principle, technically and politically attractive due to less pollution and toxic products emissions as compared to other methods (especially traditional incineration methods). In this report, the data are organized and analyzed from a series of pyrolysis tests carried out by KTH according to a technology concept developed by Bioincendia AB. A combustion system for the pyro gas treatment is built based on the small-scale induction pyrolysis machine. The concept of the pyro gas combustion system is expressed through the block diagram and the boundary conditions are estimated according to the test data and the literature. The result of theoretical calculation indicates the boundary conditions of system are in reasonable range. The critical parameters of heat exchange unit increase the building of whole system.
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Miller, Brendon Bruce. "Hazardous emissions from co-combustion of coal, biomass and waste." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/7206.
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Bethani, Sofia. "Production of lightweight aggregates from 'energy from waste' combustion ashes." Thesis, Imperial College London, 2004. http://hdl.handle.net/10044/1/7932.
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Carlin, Nicholas Thomas. "Thermo-chemical conversion of dairy waste based biomass through direct firing." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4844.
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Growing rates of manure produced from large dairies have increased concern for
the environmental quality of nearby streams and watersheds. Typically the manure from
the freestalls on these dairies is flushed with water to a mechanical separator. Here,
flushed dairy biomass (DB) is parted into separated solids and separated liquid. The
separated liquid is discharged into lagoons for treatment and eventual land application.
This thesis proposes thermodynamic models for firing DB in small scale boiler
systems that would eliminate land application and lagoons, which are being claimed to
be the source of nutrient leaching and overloading.
Fuel analysis of flushed DB from a dairy in central Texas show that it contains
93%moisture (%M), 3%ash (%A), and 4%combustibles (%Cb), while separated DB
solids contain 81%M, 2%A, and 17%Cb. The dry, ash-free higher heating value of DB
is approximately 20,000 kJ/kg. Using dry, ash-free results, computations can be made
over ranges of %M and %A. For example, DB containing 70%M requires 9.74%Cb to
vaporize all moisture and produce gaseous products of combustion at 373 K, but requires
17.82%Cb to burn in a regenerative combustor with a flame temperature of 1200 K. Separated solids that are pressed in an auger to 70%M (3%A and 27%Cb) can
burn at 1200 K with exhaust temperatures of up to 1130 K and a minimum required heat
exchanger effectiveness of 15%. Pressed solids can thus be fired in a boiler, where the
remaining separated liquid can be used as feed water. The pressed solids only can
release about 30% of the heat required to vaporize the remaining unclean feed water.
However, pressed DB solids can be blended with drier fuels to vaporize almost all the
unclean water. The low quality steam produced from the unclean water can be used in
thermal processes on the farm.
A similar system can be developed for vacuumed DB without the need to
vaporize unclean feed water. As for large dairies with anaerobic digester systems
already installed, directly firing the produced biogas in a small scale boiler system may
be another way to similarly vaporize the remaining effluent.
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Suksankraisorn, Kriengkrai. "Co-combustion of municipal solid waste and thailignite in a fluidized bed." Mulhouse, 2002. http://www.theses.fr/2002MULH0713.
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On étudie les principales caractéristiques de la co-combustion des ordures ménagères (OM) et du lignite Thai͏̈landais. Les sorties aléatoires du système (yj) , liées à l'alimentation du solide (ui) et à la distribution d'air (uo) dans le réacteur en lit fluidisé sont filtrées et analysées autour d'états stationnaires. La co-combustion réduit les émissions de S02 et augmente légèrement celles des NOx en réduisant sensiblement l'efficacité de la combustion. Un rapport air secondaire sur air primaire (uo =0. 2) pour 40 à 60 % d'excès d'air (U2) et une composition massique de 20 % en OM permet de maximiser l'efficacité de la combustion et de minimiser les taux de rejet en CO et NOx. Les rejets de S02 peuvent être fortement réduits par addition de chaux- L'analyse statistique par des fonctions de corrélation, l'étude de la puissance spectrale des signaux filtrés (yj) de température et de concentration des gaz en sortie de réacteur montrent une compétition entre des réactions en phase gaz donnant lieu à un phénomène périodique. Des modèles linéaires obtenus montrent qu'il est possible de contrôler la combustion, mais de grandes erreurs résiduelles pour les sorties CO et S02 devraient être prises en compte par des modèles non-linéaires plus complexes.
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Aripin, Wildan. "Trace element emissions from co-combustion of coal, biomass and waste." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405761.
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Mears, Kevin S. "Water distillation using waste engine heat from an internal combustion engine." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36725.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.<br>Includes bibliographical references (leaf 36).<br>To meet the needs of forward deployed soldiers and disaster relief personnel, a mobile water distillation system was designed and tested. This system uses waste engine heat from the exhaust flow of an internal combustion engine to vaporize water for the purpose of removing impurities. The vapor is condensed back down to water in a finned condenser that experiences forced convection. The system pumps heat transfer oil through a 0.61 meter long, cross flow, annulus-type heat exchanger installed over a section of exhaust pipe where the oil experiences a AT of 7°C. The hot heat transfer oil is then piped to a boiler where it releases its heat to the water and returns to the exhaust heat exchanger to be reheated. Testing demonstrated that the system has a heat up time of 30 minutes, and a steady state distillation rate of 2 gallons per hour. In steady state, the system removes and transfers heat from the exhaust at a rate of 4600 Watts.<br>by Kevin S. Mears.<br>S.B.
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Hedman, Björn. "Dioxin emissions from small-scale combustion of bio-fuel and household waste." Doctoral thesis, Umeå University, Chemistry, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-593.
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<p>Denna avhandling behandlar rökgasutsläpp av persistenta organiska föroreningar, framförallt dioxiner, vid förbränning av fasta biobränslen och torrt hushållsavfall i relativt små anläggningar (5-600 kW) utan avancerad rökgasreningsteknik.</p><p>Samförbränning av avfall och biobränsle i effektiva mindre biobränslepannor testades som en alternativ strategi till den vanligen förekommande storskaliga hanteringen och förbränningen fast hushållsavfall. Medan storskalig förbränning av avfall ger investeringsmässiga fördelar med rökgasreningsteknik etc. kan små lokala anläggningar ha transportmässiga fördelar och möjligheter till utnyttjande av lokala biobränsletillgångar. Källsorterat, torrt, brännbart hushållsavfall insamlades från hushåll i glesbygd och samförbrändes i brikettform med energigräset rörflen i 150-600 kW biobränslepannor. Endast undantagsvis understeg dioxinemissionerna gällande gränsvärden för avfallsförbränning och nivåerna av väteklorid i rökgas översteg gränsvärdena flerfaldigt. Det bedömdes att någon form av extra rökgasrening är nödvändig för att säkerställa nivågränserna. Dioxiner hittades också i det eldade avfallet, framförallt i textilfraktionen. Dioxinmängderna i rökgaserna var oftast lägre än i det ingående bränslet.</p><p>Intermittent pelletseldning gav oväntat höga utsläpp av dioxiner med en emissionsfaktor på 28 ng(WHO-TEQ)/kg. Vedeldning i en modern miljömärkt villapanna gav betydligt lägre utsläpp av dioxiner än eldning i en gammal kombipanna och eldning med full lufttillförsel, som kan jämföras med användning av ackumulatortank, resulterade i upp till 90% minskning av utsläpp av dioxiner jämfört med eldning med reducerat lufttillskott (’pyreldning’). Eldning av plastavfall i en vedpanna gav höga utsläpp av dioxiner.</p><p>Okontrollerad förbränning av trädgårdsavfall och hushålls avfall i tunna eller som öppen eld ’bakgårdsbränning’, gav stora variationer i utsläppsnivåer som bara delvis kunde kopplas till avfallsinnehåll. Resultaten visar att denna typ av förbränning kan vara en betydande källa till dioxiner i miljön, och ett emissionsfaktorintervall på 4-72 ng (WHO-TEQ)/kg föreslås för bedömningar av utsläpp från backgårdsbränning av avfall med låga eller måttliga klorhalter.</p><p>En sammanfattande slutsats av alla försök är att dioxin utsläpp beror på komplicerade samband mellan bränsleinnehåll och förbränningsbetingelser. Bränslen med mycket höga klorhalter av ger oftast högre utsläpp av dioxiner än bränslen med låga klorhalter medan små skillnader döljs av variationer i förbränningsbetingelser.</p><br><p>This thesis deals with emissions of persistent organic pollutants, primarily dioxins, from the combustion of solid biofuels and dry combustible household waste in relatively small facilities, 5-600 kW, without advanced air pollution controls.</p><p>Co-combustion of waste and biofuel in effective small boilers was tested as an alternative to prevailing large-scale management and combustion strategies for handling municipal solid waste. This approach includes no advanced air pollution control systems, but offers two advantages: limiting transport and providing scope to use local biofuel resources. Source-sorted, dry, combustible household waste was collected from households in a sparsely populated area and co-combusted as briquettes together with reed canary-grass in 150-600 kW biofuel boilers. Most trials showed difficulties to meet regulative limits for the emissions of dioxins valid for incineration of MSW and the regulated limits for emissions of hydrochloric acid were exceeded manifold. It was concluded that additional flue-gas cleaning will be needed to ensure that emissions are sufficiently low. Dioxins were also found in the waste, especially in the textile fraction. The mass of dioxins in the flue-gas emissions was generally lower than the mass in the fuel input.</p><p>Intermittent combustion of wood pellets in a residential boiler resulted in an unexpectedly high dioxin emissions factor of 28 ng (WHO-TEQ)/kg fuel. Combustion of wood in a modern environmentally certified boiler yielded considerably lower dioxin emissions than combustion in an old boiler, and combustion with a full air supply, i.e. with use of heat storage tank, resulted in up to 90% reductions in dioxin emission factors compared to combustion with reduced air supply. Combustion of plastic waste in a residential wood boiler resulted in high emissions of dioxins.</p><p>Tests of uncontrolled combustion of garden and household waste in barrels or open fires, ‘backyard burnings’, resulted in emissions with large variations that could only be partly correlated to the waste constituents. The results imply that this may be an important source of dioxins in the environment and an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested for estimating emissions from backyard burnings of lightly and moderately chlorine-contaminated waste.</p><p>A summarized conclusion from all of the experiments is that predicting emission levels from waste contents is not straightforward (except that fuels with very high chlorine levels will usually result in high levels of dioxins in flue-gas emissions). Moderate differences in chlorine levels will usually be masked by the effect of variations in combustion conditions.</p>
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Hedman, Björn. "Dioxin emissions from small-scale combustion of bio-fuel and household waste /." Umeå : Department of Chemistry, Umeå University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-593.
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Trouillet-Richaud, Raphaelle. "Toxic emissions from the gasification and combustion of coal and biomass waste." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313145.
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Hassan, Sajid. "Emissions of nitrogen oxides, particulates and toxic metals from fossil-and -waste-fired combustors." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267994.
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Walsh, Allan R. "A computer model for in-flight black liquor combustion in a kraft recovery furnace." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/7060.
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Gewald, Daniela [Verfasser]. "Waste heat recovery of stationary internal combustion engines for power generation / Daniela Gewald." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045987735/34.
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Hosseinian, Aida. "Thermodynamic Equilibrium Prediction of Corrosion Tendency in Fluidized-Bed Combustion of Solid Waste." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-13619.
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Global warming and air pollution are two issues of greatest concerns to human life in recent years. Environmental concerns and econimal/political independency of fossil fuels have been the driving force of developing interest in renewable resources of energy for many countries. Different type of waste-derived fuels such as biomass, municipal solid waste and industrial waste are interesting energy resources for energy producing companies. There are mainly two main paths when it comes to waste-to-energy industry, which are thermal treatment of waste, as well as biochemical treatment. Thermal treatment of waste to produce energy could benefit both for hygienic consideration of waste management and avoiding waste landfill.Heat and power generation through combustion of waste or biomass has several environmental, and economical advantageous over utilization of fossil fuels. Thermal conversion of waste and biomass fuels, however, has some challenges mainly due to their chemical composition and high alkali metals (potassium and sodium) content. Combustion of these fuels usually can result in some operational challenges such as deposition, fouling, bed agglomeration and corrosion in different part of the boiler. The less reactive and non-combustible part of the fuel known as ash-forming matter has a major role in these operational challenges. Ash related problems in waste-to-energy boilers lead to lower efficiency, high maintenance costs and equipment failure. Therefore, investigating the chemical composition of fuel and ash-forming matter is essential prior to thermal conversion of waste-derived fuels. High-temperature corrosion due to formation of corrosive alkali chloride compounds during combustion is one of the main ash-related concerns in boilers.This study investigated high-temperature corrosion in circulating fluidized-bed (CFB) combustion of solid waste. Flue gas composition of solid waste combustion in the CFB boiler was analysed in two cases: combustion of the reference fuel, and combustion of the “same” fuel with a sulphur containing additive (ammonium sulphate), to decrease the corrosive alkali chlorides in the flue gas. Chemical fractionation was carried out for fuel samples to determine the reactive and less-reactive fraction of ash-forming matter. A thermodynamic equilibrium model was developed using Factsage thermochemical software, to predict the chemical composition of the flue-gas with a special focus on corrosive alkali chlorides. The modelling results were evaluated using In-situ Alkali Chloride Monitoring (IACM) results obtained during the full-scale combustion measurements.
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Ip, Leong-Teng. "Comprehensive Black Liquor Droplet Combustion Studies." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd677.pdf.
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Hegarty, Kieran Thomas. "Investigation of UEGO sensors and their application to novel engine measurements." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708615.
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Hedberg, Erika, and Helén Danielsson. "Potential for Absorption Cooling Generated from Municipal Solid Waste in Bangkok : A Comparison between Waste Incineration & Biogas Production with Combustion." Thesis, Linköpings universitet, Industriell miljöteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57240.
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This master’s thesis has been performed in Bangkok, Thailand at the company Eco Design Consultant Co., Ltd. The aim is to investigate the possibilities to generate absorption cooling from municipal solid waste in the Bangkok area. The investigation includes a comparison between waste incineration and biogas production with combustion to see which alternative is preferable. During the investigation, a Swedish perspective has been used. The research for the report mainly consisted of published scientific articles from acknowledged sources as well as information from different Thai authorities. Also, experts within different areas were contacted and interviewed. In order to determine which of the two techniques (waste incineration or biogas production with combustion) that is best suited to generate absorption cooling, a model was designed. This model involved several parameters regarding e.g. plant efficiency, amount of treated waste and internal heat usage. As for the results of the model, three parameters were calculated: the generated cooling, the net electricity generation and the reduced greenhouse emissions. The overall Thai municipal solid waste generation in Thailand is estimated to approximately 15 million tons per year and the majority of the waste ends up at open dumps or landfills. There are only two to three waste incinerators in the country and a few projects with biogas generation from municipal solid waste. The main electricity is today generated from natural gas which makes the majority of the Thai electricity production fossil fuel based. As for absorption cooling, two applications of this technique has been found in Thailand during the research; one at the Naresuan University and one at the Suvarnabhumi airport in Bangkok. The model resulted in that the best alternative to power absorption cooling technique is waste incineration. This alternative has potential to generate 3200 GWh cooling per year and 1100 GWh electricity per year. Also, this alternative resulted in the largest decrease of greenhouse gas emissions, ‐500 000 tons per year. The model also showed that the same amounts of generated cooling and electricity can never be achieved from biogas production with combustion compared to waste incineration. Regardless, waste incineration has an important drawback: the citizens of Thailand seem to oppose further development of waste incineration in the country. The biogas technique seems more approved in Thailand, which benefits this alternative. Due to the high moisture and organic content in the municipal solid waste, a combination between the two waste handling alternatives is suggested. This way, the most energy can be withdrawn from the waste and the volume of disposed waste is minimized. Our overall conclusion is that the absorption cooling technique has great potential in Thailand. There is an increasing power‐ and cooling demand, absorption cooling generated from either or both of the alternatives can satisfy these demands while reducing greenhouse gas emissions. We also believes that the cost for using absorption cooling has to be lower than for the current compression cooling if the new technique is to be implemented further.
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Pandelova, Marchela Edvart. "Emissions minimization of chlorinated micropollutants in coal solid waste co-combustion by primary measures." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974171158.
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Ting, Chi-ho, and 丁智浩. "Review of waste co-combustion in Industrial facilities and its applicability to Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31255991.
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Kleiss, Torsten [Verfasser], and Hans Wilhelm [Akademischer Betreuer] Alfen. "Institutional Arrangements for Municipal Solid Waste Combustion Projects / Torsten Kleiss ; Betreuer: Hans Wilhelm Alfen." Weimar : Professur Betriebswirtschaftslehre im Bauwesen, 2008. http://d-nb.info/1116609460/34.
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Rhea, Lisa R. "Mineral Solubilization from Municipal Solid Waste Combustion Residues: Implications for Landfill Leachate Collection Systems." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000534.
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Banzaert, Amy 1976. "Viability of waste-based cooking fuels for Developing countries : combustion emissions and field feasibility." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79158.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (p. 99-109).<br>Biomass-derived cooking fuels are used by three billion people worldwide. The drawbacks of such fuels, typically wood or wood-derived charcoal, include health hazards, negative environmental effects, and perpetuation of poverty. Briquettes made from various waste materials have been proposed as an alternative to address these issues. The purpose of this work is to understand whether such fuels are viable as compared to wood charcoal considering toxicity, usability, and economic criteria. Briquettes made from carbonized agricultural waste (AWC) using a process developed by MIT's D-Lab were investigated. These briquettes were comparable to wood charcoal in terms of energy density, carbon monoxide, and polycyclic aromatic hydrocarbon emissions. Particulate matter emissions from these briquettes were 3-5 times higher but the emissions were only dominant during the initial stages of the fire. Methods for mitigating these emissions are proposed. Ultra-fine particles from wood charcoal and AWC were characterized, offering a novel understanding of these emissions. The effect of variations in raw material inputs on combustion emissions was documented and manure was found to be a promising binder material. Field studies were conducted on AWC, assessing cooking fuel emissions in households in Nicaragua, ascertaining end user perception of the fuel, piloting production with a women's cooperative, and conducting an economic analysis of the viability of this production model. Emissions were found to be comparable to wood, user perception was cautiously positive, and production was hypothetically profitable if systems are introduced effectively. Briquettes produced in Haiti from paper waste and fabric scraps were also studied and found to be highly problematic from the perspective of emissions and cooking performance. Most concerning from a health perspective is the increased particulate emissions, as compared to wood charcoal, by a factor of up to 45. These types of briquettes are being disseminated and no prior art on their emissions has been identified. In summary, AWC has promise as an alternative fuel but care must be taken in terms of particulate matter exposure and minimizing deviation from the studied briquette formula. Any alternative fuels should not be introduced until the emissions hazards and cooking performance limitations are addressed.<br>by Amy Banzaert.<br>Ph.D.
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Saleh, Mostafa, and Sandberg Anton Hedén. "IMPLEMENTATION OF OXYFUEL COMBUSTION IN A WASTE INCINERATION CHP PLANT : A Techno-Economic Assessment." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55210.
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Global energy demand is predicted to rise in the coming decades, necessitating a shift to renewable energy sources to mitigate greenhouse gas emissions. However, due to the inability to supply renewable energy around the clock, it is estimated that only by adding an important technology, carbon capture and storage (CCS), it could be possible to reduce 80% of the 1990s greenhouse gas emissions. CCS aims to reduce anthropogenic carbon emissions by capturing CO2 from flue gases, transporting, and permanently storing or reutilizing industrially. The CCS approach includes three technologies: post-combustion capture, pre-combustion capture, and oxyfuel combustion, with the latter being the emphasis of this thesis. Based on the case study of Mälarenergi’s Refused-derived waste-fired CHP plant, this thesis investigates the viability of converting existing non-fossil fueled CHP plants to oxyfuel combustion. A thorough technical investigation based on analyzing the impact of oxyfuel combustion on system performance was conducted through system modeling using a process simulator, Aspen plus. The model in this thesis considers the development of an air separation unit (ASU), a CHP plant, and a cryogenic CO2 purification unit (CPU). All of which are validated through calibration and comparison with real-world data and similar work. To investigate the influence of employing oxyfuel combustion on the generation of both heat and electricity, two different scenarios were comprised, including recirculating flue gas before and after flue gas condensation. In addition, an analysis of the oxygen purity was conducted to assess the most optimal parameters with the least impact on system performance. Moreover, a detailed eco- nomic assessment comprising the costs of integrating oxyfuel combustion was also conducted. The findings of this thesis show that integrating waste incineration CHP plants with oxyfuel combustion for CO2 capture entails promising features under the condition of 97% oxygen purity and a flue gas recirculation system taking place after flue gas condensation. This is owing to (i) modest imposed energy penalty of approximately 8.7%, (ii) high CO2 recovery ratio, around 92.4%, (iii) total investment cost of approximately 554 M$ during a 20-year lifetime, and (iv) cost of captured CO2 of around 76 $/ton. Aside from system modeling, this thesis pre- sents an overview of the current state-of-the-art technology on the different separation and capture mechanisms. It is important to highlight that the goal of this thesis is not to provide a comprehensive review but rather to present an overall picture of the maturity of the different mechanisms. The findings point to the cryogenic separation mechanism as the most mature technology for both oxygen production and capturing of CO2 during oxyfuel combustion.
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Jenkinson, Philip. "A new classification system for biomass and waste materials for their use in combustion." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33076/.
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The use of biomass derived solid fuels for electricity generation in combustion, gasification and pyrolysis plant has received increasing levels of interest for commercial operation in recent years. However, there are limited tools available which allow a prediction of the performance of these fuels during thermochemical transformation given an understanding of their original chemical structure. As such, this investigation has concentrated on the derivation of a simply utilised classification system able to predict a series of important fuel combustion characteristics given an understanding of both the organic and inorganic chemical and structural composition of any lignocellulosic biomass fuel. A prediction of volatile matter content and char yields during pyrolysis has been made using correlation with aromatic carbon, potassium and calcium contents using both thermogravimetric slow heating and simulated pulverised fuel (PF) entrained flow rapid heating. Alongside this, investigation of the impact of biomass composition, namely aromaticity and alkali/alkaline earth metal concentrations, on char structure and oxidative char reactivity of simulated PF chars has been conducted. Experimental investigation has involved the pre-treatment of a wide range of commercially available biomass fuels including softwood, hardwood, herbaceous and agricultural waste materials to remove both lignin and ion exchangeable mineral species. In addition to this, torrefaction has been utilised to increase the aromatic character of chosen fuels. This has allowed a quantification of the impact of aromaticity and mineral matter concentration on pyrolysis and char combustion reactions to be derived for a wide range of fuel aromaticity and mineral matter contents. Considerable success has been achieved in the classification of an array of lignocellulosic biomass. Accurate prediction of pyrolysis char and volatile matter yields under both slow and rapid entrained flow drop tube heating conditions have been attained using simple empirical correlations with fuel aromatic carbon and alkali/alkaline earth mineral species concentrations (K+Ca being utilised here). This classification system has relied upon the clear linear correlation observed between aromatic carbon content and char yield in the absence of mineral matter influences (R2 of 0.98 and 0.95 being observed for demineralised biomass under slow and rapid heating pyrolysis respectively). In addition to this, the relative enhancement of char yield due to mineral matter interaction with varying concentration of K and Ca within the fuel has been quantified and is used to calculate total char yields. The empirical relationship derived under slow heating takes the following form: Slow Heating Char Yield=(1×Aromatic Carbon )+(16.1 ×(K+Ca) ) Where slow heating char yield is the char yield wt% on a dry ash free basis (daf), aromatic carbon is the wt% daf aromatic carbon content of the biomass and K+Ca is the wt% K+Ca content of the raw fuel on a dry basis. This relationship applies below K+Ca contents of 0.6 wt% db, beyond this a fixed additional char yield of 9.76 wt% daf can be applied as a quantification of the influence of enhanced char yield due to mineral activity as the second term in the above equation. For rapid heating entrained flow pyrolysis the empirical prediction of char yield is conducted as follows: Rapid Heating Char Yield=(0.58×Aromatic Carbon )+(2.43 ×(K+Ca) ) Strong linear correlations of predicted vs. observed char yield have been derived with correlation coefficient R2 = 0.96 and 0.99 with mean relative errors of 7.8 and 8.4% for slow and rapid heating pyrolysis respectively. Furthermore, the influence of biomass aromaticity and active mineral content on char formation processes, the form of chars generated under PF like devolatilisation conditions and their subsequent oxidation reactivity has been studied in detail. Both alkali/alkaline earth mineral matter content (primarily K and Ca) and aromaticity are instrumental in determining the porosity, morphology and surface area of simulated PF chars. Due to its tendency to soften during heat treatment lignin is shown to produce low surface area, non-porous chars under slow heating and this behaviour drives a reduction in char surface area and combustion reactivity with increasing aromatic carbon content. Although char surface areas have been seen to be negatively correlated with increasing potassium and calcium content this may be due to ash blockage of char pore structures. However, the likelihood of a negative impact of mineral enhanced charring has been discussed. K catalysis of combustion reactions is clearly evident in apparent and inherent char reactivities; however, easy quantitative assessment of this influence has been prevented by the clear complexity of mineral behaviour during the pyrolysis process. The development of char structure and reactivity as a function of char combustion degree has also been investigated under entrained flow combustion conditions. The results of this study indicate that by accurately quantifying aromatic carbon, potassium and calcium contents, all lignocellulosic fuels can be classified in terms of their behaviour during pyrolysis (volatile matter and char yields), the form of char structures generated (surface area and porosity) and char combustion reactivity. It is hoped that this relative classification will shed light on the predicted performance of biomass fuels for use in combustion driven power generation infrastructure, especially in pulverised fuel applications.
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DMITRIJEVAS, CIBELE. "Analise de ecoeficiencia de tecnicas para tratamento e disposicao de residuos solidos urbanos." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9508.
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Made available in DSpace on 2014-10-09T12:27:27Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:06:46Z (GMT). No. of bitstreams: 0<br>Dissertacao (Mestrado)<br>IPEN/D<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Patumsawad, Suthum. "Co-firing of high moisture content MSW with coal in a fluidised bed combustor." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339933.
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Mathews, Lopez Francisco. "A Multi-Criteria Decision-Making Model for Evaluation of Waste-to-Energy Technologies from Municipal Solid Waste| Combustion or Gasification for Puerto Rico?" Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10845962.
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<p> The island of Puerto Rico, a commonwealth of the United States of America, has a population of 3,725,789 according to the 2010 census, and generates 11,100 tons daily of waste. In the Island, landfilling is the dominant form of waste disposal. Most municipal solid waste landfills (MSWLF) in Puerto Rico are a principal source of land, water, and air pollution. In addition, the scarcity of appropriate land to open new landfill facilities make this type of waste disposal an unsustainable form of waste management for the Island. </p><p> This study evaluated the current situation of the MSWLFs in Puerto Rico and the geographic limitations of continuing with this type of waste disposal on the Island. As alternatives to this problem, the principal waste-to-energy (WTE) technologies, combustion and gasification, are evaluated as environmentally responsible forms for disposal of non-recycled waste. </p><p> The evaluation methodology used is based on a multi-criteria decision-making model that uses a subjective rank-order weighting method. Evaluation of WTE technologies is performed by comparing dissimilar indicators in five interest areas: technical, economic, environmental, socio-political, and risk. The methodology is composed of two-components: an expert survey and data analysis. </p><p> An evaluation of the environmental interest area was performed to assess which of the WTE technologies studied herein, combustion or gasification, is more environmentally responsible. In addition, using the relevant scores in different interest areas, they were evaluated to determine the economic benefits of these WTE technologies as viable waste management alternatives for Puerto Rico.</p><p>
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Yurdakul, Yorulmaz Sema. "Investigation Of Emissions And Combustion Kinetics Of Waste Wood Samples With Thermal And Spectral Methods." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607570/index.pdf.
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The mechanisms and kinetics of combustion of waste wood as well as the phases during combustion processes are important to eliminate these wastes without any possible damage to environment. In the present study, combustion mechanisms, activation energy and pre-exponential constants, and phases of combustion were investigated for untreated natural pine and treated Medium Density Fiberboard (MDF), plywood and particleboard samples that involve some chemicals and additives. Waste wood samples were heated in air at 10, 20 and 30oC/min heating rates in a Thermo Gravimetric Analyzer (TGA) from room temperature to 900oC. Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) curves for all samples were obtained. The gases formed during combustion reactions were directly fed to a Fourier Transform Infrared Spectroscopy (FTIR) instrument coupled to TGA. Emission characteristics of the samples were determined in-situ by using the FTIR spectrums.
As a result of TG analysis, thermal decomposition of treated samples was observed at lower temperatures as compared to the untreated pine sample because of the catalyzing effects of the chemicals in the treated samples.
Therefore, there were less flammable products, lower weight losses in the main oxidation region, decrease in the max. weight loss temperatures and formation of more char for treated samples as compared to untreated pine sample. In other words, chemicals used during production of these samples lead to decrease in the combustibility of the treated samples.
Thermal kinetic constants for the samples were calculated by using Coats Redfern and Broido Methods. In order to find out the mechanisms responsible for the oxidation of the waste wood samples in different regions, six solid state mechanisms of Coats Redfern Method were tested.
As a result of FTIR analysis of the emitted gases from TG analysis, several chemical groups were detected from pine and treated samples. Combustion of all samples revealed some gases containing aromatics, C-H groups, CO2 and CO. However, there were some toxic and carcinogenic gases like formaldehyde, isocyanate group, ammonia, phenyl group and benzoylbromide among the emissions of treated samples which need utmost attention when recovering energy from treated waste woods.
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Nordin, Anders. "On the chemistry of combustion and gasification of biomass fuels, peat and waste : environmental aspects." Doctoral thesis, Umeå universitet, Kemiska institutionen, 1993. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-110672.
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Farid, Muhammad Usman [Verfasser]. "CFD modeling of combustion of solid waste materials with low melting points / Muhammad Usman Farid." Magdeburg : Universitätsbibliothek, 2018. http://d-nb.info/1154485668/34.
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Nachtrodt, Frederik <1984>. "Development of a method for plasma - induced combustion of intermediate to low-level radioactive waste." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5793/.
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This work demonstrates that the plasma - induced combustion of intermediate to low-level radioactive waste is a suitable method for volume reduction and stabilization. Weaknesses of existing facilities can be overcome with novel developments.
Plasma treatment of LILW has a high economical advantage by volume reduction for storage in final repositories.
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Seneviratne, Hemantha Revata. "Evaluating sorbents produced from waste to remove mercury in simulated flue gases from coal combustion." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/11231.
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Coal-fired utility plants are the largest anthropogenic source of mercury emiSSIOns. Mercury abatement legislation for these plants is in place in Canada and U.S.A. Several facilities are achieving mercury emission reductions by using commercial activated carbons. However, these carbons are expensive. The present project aimed to determine mercury capture efficiencies of some fly ashes and sorbents produced from scrap tyre rubber and sewage sludge, compared to the effectiveness of commercial active carbons. E.U. legislation limits the methods available for disposing of waste materials, using them to manufacture sorbents provides a cost-effective disposal solution. A novel bench scale fixed-bed sorbent test system was designed and built for evaluating mercury capture efficiencies of sorbents by exposing the samples to different gaseous atmospheres. Pre-treating selected sorbents with a gas stream containing either NOx or HCl gave information on the effect of acid gases. Thermal desorption experiments completed on spent sorbents provided indications regarding the adsorption process.
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Lundholm, Karin. "Fate of Cu, Cr, As and some other trace elements during combustion of recovered waste fuels." Doctoral thesis, Umeå : Department of Applied Physics and Electronics, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1132.
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Čepanko, Violeta. "Investigation of fermented waste and technologies of disposal." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100628_092621-12161.
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Object of the work – the fermented solid waste (substrate) and liquid (filtrate) fractions and their technologies of disposal. The key aim of this work is to analyse and evaluate the possibilities of using fermented wastes (sewage sludge, swine and poultry manure, fruit and vegetable waste, and grain) for fertilisation, composting and incineration taking into account their elementary composition and a level of pollution with heavy metals. Carry out an evaluation of gaseous pollutant (NOx) emissions from the process of incineration through the employment of a digital model.<br>Tyrimų objektas – fermentuotų atliekų kietoji (substratas) ir skystoji (filtratas) frakcijos bei jų panaudojimo technologijos. Darbo tikslas – išnagrinėti bei įvertinti fermentuotų atliekų (nuotekų dumblo, kiaulių ir vištų mėšlo, vaisių su daržovėmis bei žliaugto) panaudojimo tręšimui, kompostavimui bei deginimui galimybes atsižvelgiant į jų elementinę sudėtį ir užtaršos lygį sunkiaisiais metalais. Atlikti šių atliekų deginimo proceso metu išsiskiriančių dujinių teršalų (NOx) įvertinimą naudojant skaitinį modelį.
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Singh, Surjit. "Waste tyres and plastics as potential reburn fuels for reduction of NOx in large scale combustion systems." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503270.
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Martinez, Jason A. (Jason Alexander). "Improvement of kiln design and combustion/carbonization timing to produce charcoal from agricultural waste in Developing countries." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/40452.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.<br>Includes bibliographical references (leaf 25).<br>Current economic conditions in third world countries like Haiti are so poor that the majority of the population has no access to energy sources that people in the first world take for granted. In Haiti the last two percent of the forests are being cut down to provide energy for basic cooking to survive. In response to the situation, MIT professors and students are designing a multi-step process for making charcoal briquettes from local agricultural waste products, or biomass. The process involves the combustion and carbonization of biomass at sustained high temperature in an air-tight metal barrel kiln to produce char. The char produced from Haiti's main agricultural waste product, bagasse, must be powderized, mixed with a binder, compressed into briquettes, and finally baked. The purpose of the thesis was to improve on key areas of the charcoal making process. The goals were to: conduct and investigation into alternative kiln layouts; address safety concerns with water boiling, briquette baking, and bottom venting; design of a method for uniform and complete briquette baking using heat from the carbonizing kiln; and gain a better understanding of the importance combustion timing and sealing.<br>(cont.) Design for affordable, low level manufacturing would be an important requirement as well. The results of the thesis were: an analysis of possible kiln designs based on the supplies typically available in developing countries; improvements to safety by using wire tethers on kiln hardware to allow kiln operators to keep a safe distance; a proposed new design for a briquette baking box with multiple briquette banks; and combustion timing and kiln insulation techniques to maximize char output.<br>by Jason A. Martinez.<br>S.B.
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Moradian, Farzad. "Ash Behavior in Fluidized-Bed Combustion and Gasification of Biomass and Waste Fuels : Experimental and Modeling Approach." Doctoral thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-9563.
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Over the past few decades, a growing interest in the thermal conversion of alternative fuels such as biomass and waste-derived fuels has been observed among the energy-producing companies. Apart from meeting the increasing demand for sustainable heat and power production, other advantages such as reducing global warming and ameliorating landfilling issues have been identified. Among the available thermal conversion technologies, combustion in grate-fired furnaces is by far the most common mode of fuel conversion. In recent years, Fluidized-Bed (FB) technologies have grown to become one of the most suitable technologies for combustion and gasification of biomass and waste-derived fuels.In spite of the benefits, however, some difficulties are attributed to the thermal conversion of the alternative fuels. Ash-related issues could be a potential problem, as low-grade fuels may include considerable concentrations of ash-forming elements such as K, Na, S, Ca, Mg, P, Si and Cl. These elements undergo many undesirable chemical and physical transformations during the thermal conversion, and often cause operational problems such as deposition-related issues, slag formation in furnaces, corrosion of the heat transfer surfaces, and bed agglomeration of the fluidized-beds. Ash-related problems in the utility boilers are a major concern that may result in decreased efficiency, unscheduled outages, equipment failures, increased cleaning and high maintenance costs.This thesis investigated the ash behavior and ash-related problems in two different FB conversion systems: a Bubbling Fluidized-Bed (BFB) boiler combusting solid waste, and a Dual Fluidized-Bed (DFB) gasifier using biomass as feedstock. Full-scale measurements, chemical analysis of fuel and ash, as well as thermodynamic equilibrium modeling have been carried out for the BFB boiler (Papers I-IV), to investigate the impact of reduced-bed temperature (RBT) and also co-combustion of animal waste (AW) on the ash transformation behavior and the extent of ash-related issues in the boiler. For the DFB gasifier (Paper V), a thermodynamic equilibrium model was developed to assess the risk of bed agglomeration when forest residues are used as feedstock.The experimental results showed that the RBT and AW co-combustion could decrease or even resolve the ash-related issues in the BFB boiler, resulting in a lower deposit-growth rate in the superheater region, eliminating agglomerates, and a less corrosive deposit (in RBT case). Thermodynamic equilibrium modeling of the BFB boiler gave a better understanding of the ash transformation behavior, and also proved to be a reliable tool for predicting the risk of bed agglomeration and fouling. The modeling of the DFB gasifier indicated a low risk of bed agglomeration using the forest residues as feedstock and olivine as bed material, which was in good agreement following the observations in a full-scale DFB gasifier.