Microwave heating has unique advantages compared to convection-radiation heating methods including fast heating rate and selective heating of objects. This thesis studied two applications of microwave heating in the environmental field: adsorbent regeneration and oil sands coke activation. The thermal behavior during microwave heating of select adsorbents when dry or saturated with selected adsorbates was studied to assess the potential for using microwave heating to regenerate adsorbents. Strong microwave-absorbing adsorbents depicted faster heating rate when dry. Weakly microwave-absorbing adsorbents depicted faster heating rate when saturated with polar adsorbates. Fast activation of oil sands coke using microwave heating and KOH was successfully completed. The iodine number of the activated delayed coke obtained after 10 minutes of microwave activation was 1130 mg/g. The short activation time and simplicity of the process demonstrate that microwave-activation is a promising approach to convert oil sands coke into activated carbon adsorbent with high adsorption capacity. / Environmental Engineering

We have carried out a theoretical and an experimental study of thermal effects arising in bulk high-Tc superconductors. The theoretical study has allowed us to predict the self-heating behaviour. We have calculated the temperature evolution. We have shown the existence of a forbidden temperature window, and we have determined the analytical expression of a threshold field (Htr2) separating the « middle» and the «high» dissipation state . From a numerical modelling of a short cylinder, we have determined the time and spatial dependance of dissipated power and temperature within the sample. We have shown that the temperature rise is the highest along the corner location where the dissipated power is maximum. We have designed and constructed a susceptometer for characterizing large bulk superconductors (f →32 mm). The susceptometer allows a small temperature gradient (< 0.1K) to be achieved in the presence of large heating rates. It allows large AC and DC fields to be applied simultaneously, and was upgraded to measure simultaneously local temperatures and magnetic inductions. We have determined the heat transfer occuring in the susceptometer chamber. Magneto-thermal measurements with this system can be carried out with a high sensitivity and are found to be in very good agreement with the theoretical predictions. This work underlines the importance of the cooling conditions that can affect the distribution of the magneto-thermal properties within the superconductor.

The main aim of this project is to develop an ESES lab on a full scale system. The solar combisystem used is available most of the time and is only used twice a year to carry out some technical courses. At the moment, there are no other laboratories about combisystems. The experiments were designed in a way to use the system to the most in order to help the students apply the theoretical knowledge in the solar thermal course as well as make them more familiar with solar systems components. The method adopted to reach this aim is to carry out several test sequences on the system, in order to help formulating at the end some educating experiments. A few tests were carried out at the beginning of the project just for the sake of understanding the system and figuring out if any additional measuring equipment is required. The level of these tests sequences was varying from a simple energy draw off or collector loop controller respond tests to more complicated tests, such as the use of the ‘collector’ heater to simulate the solar collector effect on the system. The tests results were compared and verified with the theoretical data wherever relevant. The results of the experiment about the use of the ‘collector’ heater instead of the collector were positively acceptable. Finally, the Lab guide was developed based on the results of these experiments and also the experience gotten while conducting them. The lab work covers the theories related to solar systems in general and combisystems in particular.

Cultural heritage and human comfort: The issue of indoor climate in historic buildings in the twentieth centuryI

The harsh winter conditions on the Canadian prairies impose special challenges in providing acceptable environmental conditions for broiler chickens during transportation. A research program was developed aiming to improve the transport conditions for broilers. As part of the research program, a research project was developed to design and construct an experimental trailer equipped with active ventilation and heating, to characterize the performance of the experimental trailer in field tests under Canadian Prairie winter conditions, to develop, calibrate and validate CFD models used for simulating the environmental conditions found inside the experimental trailer, and to utilize one of the CFD models to predict the performance of the experimental trailer when subjected to different operational conditions. This dissertation consists of six chapters. The first introductory chapter reviews economical, logistical and legislative aspects surrounding the poultry transport industry. This chapter also includes a discussion of important parameters for the design of an experimental transport system, a review of fundamental concepts of the Computational Fluid Dynamics (CFD) modeling method, and why CFD was chosen as a tool to complement the experimental work in this project. The second chapter reviews the designs of commercial poultry transport equipment and how they inspired the design of an actively heated and ventilated experimental vehicle. The setup of the experimental trailer was also discussed in detail. The third chapter reviews the experimental protocol used to evaluate the performance of the experimental trailer. The performance of this experimental trailer was evaluated in a series of field tests conducted under commercial loading operations, in winter conditions on the Canadian Prairies. It was found that the average load temperature varied from 7.1 to 15.6°C in the nine sts of data. The system was able to maintain an environment above 1°C. As for the humidity level inside the trailer, the majority of sensors had representative relative humidity (RH*) values between 10 and 40%, with the rest having RH* values below saturation. The fourth chapter reviews the development, calibration and validation of the 3-D CFD models developed to simulate the environmental conditions inside the experimental trailer. A total of three CFD models were developed to simulate the three different ventilation regimes encountered in field tests. Sensitivity studies revealed that inlet velocities, heat and moisture production had a great impact on the results obtained from the CFD models. The levels of porosity investigated did not play a significant role. The standard error of estimate was selected as a statistical measure to evaluate the accuracy of the CFD models against experimental data. For temperature data, its standard error of estimate varied from 3.2 to 7.3°C. For humidity ratio, its standard error of estimate varied from 1.7 to 5.0 g of water vapour per kg of dry air. The CFD models were able to recreate the temperature trends as observed from experimental data. It was concluded that these CFD models have adequate accuracy to be used as a design tool for comparative studies. The fifth chapter investigates the use of the 1-fan CFD model to study several scenarios. Three cases were investigated, based on conditions which may be encountered by the poultry transport industry. The first case examined the effects of vehicle travel speed and ambient temperature. The second case looked at the effects of bird size, loading density and ambient temperature. The last case studied the effects of side tarp insulation and ambient temperature. For the range of values examined, results from the simulations concluded that ambient temperature, bird sizes, loading density and side tarp insulation value were important factors to consider in the design of an actively ventilated poultry transport vehicle. The last chapter of this dissertation summarizes the main findings in this research project, discussed future work and presented final conclusions. Overall, this research project answered two key questions in the poultry transport research program. Firstly, the experimental work proved that the concept of active ventilation and heating is a promising option to improve the transport conditions for broiler chickens during cold ambient conditions. Secondly, the CFD work demonstrated that CFD modeling is a valuable tool for designing the next generation of actively ventilated poultry transport vehicle.

This project has been developed at the company Gavlegardarna. The companyowns a large part of the buildings of Gävle and two of them are the objective ofthe project. Gavlegardana is highly concerned about the environment; for thisreason, they cooperate on the subject with the energy management from theirtechnical department. Gävle is one of the Swedish cities where the DH (district heating) network isdistributed, arriving to most of the dwellings, industries and commercialbuildings. As DH uses environmentally friendly sources of energy,Gavlegardana is introducing it in its buildings. Electrical radiators and boilers were installed in the buildings when the price ofelectricity was more affordable than nowadays. The price of the electricity canbe considered 1,23 SEK/kWh while the DH price is 0,45 SEK/kWh. Consequently, this is another reason why the objective of the company at thepresent time is to replace electrical space heating systems by means of districtheating. The energy balance of the buildings is analysed in order to study their currentenergy situation. This entails the consideration of heat gains and lossesinvolved. The heat gains of the building are the heat from solar radiation whicharrives at the building trough the windows, the heat internally generated (bypersons, lighting and other devices) and the heat supplied. The heat losses are composed by the transmission trough walls and windows, the infiltrations, the heat used for hot tap water and the ventilation losses. An important part of the work required to calculate the energy balance hasconsisted of the collection and organization of all the data (areas, types ofmaterial, electrical devices, lighting, number of employees, opening hours...).This data comes from the drawings of the buildings provided by the companyand from the information gathered during the visits to the installation. In addition, the ventilation flows were measured in-situ using the tools provided by Theorells. Gavle Energi, the DH distributor company, has been contacted in order to fixthe cost and other details related to the district heating connection. The heatexchanger models, selected from Palmat System AB, are TP20 for Building Aand TP10 for Building B. TP20 provides 100 kW of heating and 0,4 l/s of hot tap water and TP10 provides 50 kW and 0,31 l/s respectively. The capital cost is 187500 SEK which includes the heat exchangers and the connection cost. As the secondary circuit is not currently installed because the existing system iscomposed by electrical radiators, the installation of the piping network in thebuilding has been designed. The radiators’ power is calculated taking intoaccount the need of heat in each room which is estimated as the transmissionlosses. This need of heat calculated is higher than the energy currently supplied which means that the thermal comfort is not achieved in all the rooms of the buildings. In spite of using more energy for space heating, the change of heat sourceentails a lower energy cost per year. The selected radiators are from Epeconand the investment cost (including the installation) is 203671 SEK. The brand of the selected pipes is Broson and the investment cost of the total piping system is 66000 SEK. The initial investment of the new installation is 457171 SEK, considering the DHconnection, heat exchangers, radiators and pipes. If the initial investment istotally paid in cash by the company the payback will be fulfilled in 6 years. Incase of borrowing the money from the bank (considering an interest rate of 5%), two possibilities can be considered: paying back the money in annual rates over 15 years or 30 years of maturity. The paybacks are 11 and 8 years respectively. After designing the DH piping system in the buildings, estimating the total costs of the investment and studying the project’s feasibility by suggesting different payment options, some possible energy savings are recommended.   The first of the options refers to the transmission losses trough the windowswhose values’ are considerably high. Using a glass with a lower U-value, theselosses can decrease until 66% (with triple glass windows). Consequently, thepower required for space heating can also be reduced until 26%. Regarding the ventilation, rotating heat exchangers are currently used, whichentails the problem of smells mixture detected by the users of the buildings. By changing them with flat-plate heat exchangers, the problem is solved and the efficiency is increased from 66% to 85%. The new heat exchanger cost is340387 SEK and it has a payback of 10 years.

The aim of this Project is to study the influence of high return temperatures in district heating on the costs for heat and power production in a CHP plant.When the temperatures of the water coming back to the heating plant are so high, the overall performance of heat and power production is decreased and, consequently, also the production costs. Along the project, the influence of this temperature on the different parts of a CHP plant are analysed as well as the economical impact it has. At the same time, some general impacts on the entire network are mentioned.   A real network is used in this project, and it is the net of district heating in Gävle (Sweden), and the most of the study is focus in its bigger combined heat and power production plant (CHP), called Johannes.

Abstract The behavior for MoSi2 based high temperature heating elements for resistive heating has been examined in elevated temperature and low oxygen content environment. MoSi2 spontaneously forms a protective SiO2 scale at high temperature if the amount of oxygen in the ambient atmosphere is sufficient according to the following reaction: 5MoSi2 + 7O2(g)  7SiO2 + Mo5Si3 If the oxygen content at a specific temperature is too low, SiO(g) is more stable than SiO2 and the following reaction will occur instead: 2SiO2  2SiO(g) + O2(g) Then surface will be Si-deplated and finally, the base material will be exposed. Si and Mo will oxidize and degas from the surface as SiO and MoO3 with severe diameter reduction of the heating element as a result. It is therefore of high interest to find the relationship between the maximum element temperature and the oxygen content in the ambient atmosphere to be able to fully exploit the potential of the heating elements and also to aid and help diagnose customer complaints.   After 14 full scale tests in a custom made atmospheric furnace, the following equation could be calculated: p(O2) = 1.748·100.01677·T·log(e)-10 The equation gives the minimum oxygen content at a specified temperature. The equation is based on 100 hours tests at atmospheric pressure, gas flow rate of 4 liter per minute, varying temperature and varying oxygen content. Nitrogen has been used as carrier gas for the oxygen.

Water has been heated with the sun has almost as long as there have been humans, but itis not until recently that more advanced and effective solar water heating systems havebecome common, and they are still gaining ground. Through the years new systems andnew solar collectors have been developed. In Kosovo, however, not much attention hasbeen paid to replace fossil fuels with renewable energy sources and solar water heatingsystems is a new concept.The United Nations Development Programme (UNDP) in Kosovo is working on a projecton sustainable development in Dragash Municipality in southern Kosovo. A solar waterheating system has recently been installed at the hospital in Dragash, as part of the UNDPproject. The system is a pilot project, to see how well solar energy can be used in thisarea.The existing solar water heating system at the hospital in Dragash was examined andevaluated. The possibilities of using the fundamental principle of the solar water heatingsystem at the hospital on residential houses in Dragash were looked into. Six prototypesof average residential houses in the village of Brod and Dragash Town were created. Thesolar collector size and storage needed to meet the demands for the six house prototypeswere calculated. Information on the incoming solar irradiation for each hour of a year wasobtained from the online service SoDa Solar Radiation Data. The total annual incomingsolar radiation for one square meter was calculated.The environmental, social and economic effects of solar water heating in Dragash wereconsidered and discussed. Rough economic calculations were made on the effects ofinstallation of solar water heating systems.The solar water heating system at the hospital in Dragash is a good pilot project, and islikely to work satisfyingly. The annual output effect of the system is approximately 7 400kWh. The fundamental principle needs to be altered to work on residential houses. Thesolar collector needs to be of a cheaper kind, and the collector and storage tank can be ofsmaller dimensions.Solar water heating can contribute to Kosovo’s work toward sustainable environmental,social and economic development focusing on hot water supply. Kosovo has sufficientsolar radiation for solar water heating systems to work in a satisfactory way. The outputeffect for a solar water heating system in Dragash is around 390 kWh/(m2∙year) with atotal efficiency for the system of 30%. If the solar water heating system replaces heatingby electricity the annual savings can be 31 €/m2 solar collector. The biggest obstacles forthe use of solar energy are the public’s lack of knowledge on solar water heating andenvironmental problems connected to energy, as well as economy.The work done in this thesis is a good foundation for future research on solar energy inKosovo. It can be extended and elaborated with more thorough economic calculations,since economy is an important factor in the future for solar energy. Only roughcalculations were made in this thesis, since it has a technical approach. More extensiveresearch could also be done to evaluate the possibilities of using solar water heating forspace heating. / Varmvatten har värmts med hjälp av solen nästan så länge det funnits människor, men detär inte förrän nyligen som mer avancerade och effektivare solvärmesystem har blivitvanliga, och de blir allt vanligare. Genom åren har nya system och nya solfångareutvecklats. I Kosovo däremot har inte mycket uppmärksamhet ägnats åt att ersätta fossilabränslen med förnyelsebara energikällor, och solvärme är ett nytt koncept.FN:s utvecklingsprogram (UNDP) i Kosovo arbetar med ett projekt med målet hållbarutveckling i Dragash kommun i södra Kosovo. Ett solvärmesystem har nyligeninstallerats på sjukhuset i Dragash, som en del av UNDP:s projekt. Systemet är ettpilotprojekt för att se hur bra solenergi fungerar i det här området.Det befintliga solvärmesystemet på sjukhuset i Dragash undersöktes och utvärderades.Möjligheterna att använda grundprincipen för solvärmesystemet på sjukhuset påbostadshus i Dragash undersöktes. Sex prototyper för genomsnittliga hus i byn Brod och iDragash centrum togs fram. Solfångararean och ackumulatortanksvolymen som krävs föratt klara behoven för de sex husprototyperna beräknades. Information om solinstrålningenför varje hus erhölls från SoDa Solar Radiation Data. Den totala solinstrålningen på enkvadratmeter beräknades.De miljömässiga, sociala och ekonomiska effekterna av solvärme i Dragash diskuterades.Ekonomiska överslagsberäkningar gjordes på effekterna av installation av solvärme.Solvärmesystemet på sjukhuset i Dragash är ett bra pilotprojekt, och är sannolikt attfungera tillfredsställande. Den årliga energi som systemet kan ge kommer att vara ungefär7 400 kWh. Grundprincipen behöver ändras för att fungera på bostadshus. Solfångarnabehöver vara av en billigare typ, och storleken på solfångare och ackumulatortankbehöver vara mindre.Solvärme kan bidra till Kosovos arbete mot hållbar miljömässig, social och ekonomiskutveckling med fokus på varmvattenbehov. Kosovo har tillräcklig solinstrålning för attsolvärmesystem ska fungera tillfredsställande. Med en totalverkningsgrad på 30 % för ettsolvärmesystem kan systemet ge ungefär 390 kWh/(m2∙year). Om systemet ersätteruppvärmning med el kan de årliga besparingarna bli ungefär 31 €/m2 solfångare. Destörsta hindren för användning av solenergi är allmänhetens brist på kunskap om solvärmeoch miljöproblem kopplade till energi, samt ekonomi.Arbetet i detta examensarbete är en bra grund för fortsatta studier om solenergi i Kosovo.Arbetet kan vidgas och utvecklas med mer ingående ekonomiska beräkningar, eftersomekonomi är en viktig faktor i framtiden för solenergi. Endast överslagsberäkningar gjordesi detta examensarbete, eftersom det har ett tekniskt förhållningssätt. Mer omfattandestudier kan också göras för att utvärdera möjligheterna ätt använda solvärme föruppvärmning av bostäder.

Det här är ett examensarbete som handlar om en fastighet som står på Norra Kungsgatan 37-43 som har både en värmepump och fjärrvärme för uppvärmning. Värmepumpen används i första hand och fjärrvärmen används som spets när värmepumpen inte räcker till. Detta är en ganska ovanlig kombination. Syftet med arbetet är att ta reda på om detta är en bra lösning och om lösningen är lönsam. För att få fram hur stort fastighetens energibehov är så görs beräkningar utifrån fjärrvärmedata från tidigare år samt en gammal värmepump som är utbytt sedan 2011. Byggnadens energibehov uppskattas vara ungefär 895 MWh/år och värmepumpen beräknas täcka 54 % av värmebehovet. Utifrån detta jämförs sedan kostnaden för uppvärmning av fastigheten med endast fjärrvärme med kostnaden för uppvärmning med både värmepumpen och fjärrvärme. Genom att använda värmepumpen så sparas drygt 140 000 kr per år. Det innebär att värmepumpen är lönsam rent ekonomiskt. Däremot kan användningen av högkvalitativ energi för uppvärmning diskuteras. Värme som är energi med lägre kvalitet borde i första hand användas för uppvärmning. Det för att inte slösa på våra dyrbara energiresurser och på så sätt få en hållbar utveckling. / This is an essay about a property at Norra Kungsgatan 37-43 who is heated with both a heat pump and district heating. The heat pump is used primarily and district heating is used as a tip when the heat from the heat pump is not enough. This is a pretty rare combination. The purpose of this essay is to find out if this is a good solution and if the solution is economically viable. To determine the heat demand of the property, calculations based on district heating data and heat pump data from previously years has been used. The heat demand of the building is estimated to be approximately 895 MWh/year and the heat pump is estimated to cover 54% of the heat demand. Based on this, the cost for heating the building with district heating is compared with the cost of heating the building with the heat pump and district heating. By using the heat pump, more than 140 000 kronor per year can be saved. This means that the heat pump is economically viable. However, the use of high-quality energy for heating is discussed. Heat is energy with lower quality and should be used primarily for heating. We can not waste our precious energy resources if we want to achieve sustainable development.