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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

CO2-Abtrennung aus Gasströmen durch Absorption in Poly(methyldiglykol)amin

Ohle, Andrea 16 July 2009 (has links)
In dieser Dissertation wird ein Prozess für die absorptive CO2-Abtrennung aus Gasströmen vorgestellt, der durch die Nutzung des neu entwickelten Waschmittels GenosorbN in einem Postcombustion-Prozess einen geringeren Energiebedarf als bisher bekannte Verfahren aufweist. Für die Nachrüstung bereits vorhandener Kraftwerke ist der Postcombustion-Prozess vorteilhaft, da er im Vergleich zum IGCC- oder dem Oxyfuel-Verfahren die geringsten Änderungen im Kraftwerksprozess selbst erfordert. Die bisher für die CO2-Abtrennung diskutierten Absorptionsmittel, wie z. B. MEA (Mono-Ethanol-Amin), haben allerdings vor allem in der Regeneration einen sehr hohen Energiebedarf, der vom Kraftwerk zusätzlich zur Verfügung gestellt werden muss. In Zusammenarbeit zwischen dem Institut für Verfahrenstechnik und Umwelttechnik der TU Dresden und der Clariant GmbH wurde das Absorptionsmittel GenosorbN (chemische Bezeichnung: Poly(methyldiglykol)amin) entwickelt. GenosorbN weist als Hybrid-Waschmittel gegenüber CO2 sowohl physikalische als auch chemische Bindungseigenschaften auf. Ausgehend von der Löslichkeitscharakteristik dieses Absorptionsmittels für CO2 und wichtigen Stoffwerten (z. B. Wärmekapazität und Lösungswärme von CO2) wurden mit Hilfe eines umfangreichen Versuchsprogramms an einer Technikumsanlage Betriebsparameter für einen energetisch günstigen technischen Einsatz ermittelt. Dabei hat sich herausgestellt, dass der Absorptionsprozess mit unverdünntem GenosorbN gegenüber einer MEA-Wäsche bei einem CO2-Abscheidegrad von ca. 90 % einen um ca. 20 - 27 % geringeren Energiebedarf in der Waschmittelregeneration aufweisen kann. Außerdem ist für die Desorption ein energetisch minderwertiger Heizdampf mit geringerem Temperatur- bzw. Druckniveau als bei dem MEA-Prozess ausreichend, da die Regenerationstemperatur um 40 - 50 K niedriger ist. Eine zusätzliche Druckabsenkung auf 400 mbar Absolutdruck im Desorber begünstigt die Regeneration deutlich. / This dissertation presents a process for the absorptive CO2-separation from gas streams, which shows a lower energy requirement than established methods by using the newly developed absorption liquid GenosorbN in a postcombustion-process. To retrofit an already existing power plant, the postcombustion-process is advantageous, because it needs the least changes in the power plant-process itself compared to the IGCC- or the Oxyfuel-process. The absorbents discussed for the CO2-separation up to now, for example MEA (mono-ethanol-amine), cause a high energy requirement mainly in the solvent regeneration, which has to be provided additionally from the power plant. The solvent GenosorbN (chemical notation: poly(methyldiglycol)amine) was developed in cooperation between the Institute of Process Engineering and Environmental Engineering of the Technical University of Dresden and the Clariant GmbH. GenosorbN is a hybrid-absorbent and therefore it shows both physical and chemical bonding forces. Based on the solvents characteristic of solubility for CO2 and important data on chemical media (for example heat capacity and enthalpy of solution) operating parameters for an energetic advantageous technical application were identified by a lot of test series at a pilot plant. The measurements show that the absorption process with the undiluted GenosorbN has a circa 20 - 27 % lower energy demand for the solvent regeneration compared to the MEA-process to reach a degree of separation of 90 %. Furthermore a low-value heating steam with lower temperature and therefore lower pressure level suffices because of the significant lower (40 - 50 K) regeneration temperature. An additional pressure reduction to 400 mbar absolute pressure in the regeneration column favours the solvent regeneration considerably.
162

Energy Efficiency and Carbon Management in Mineral Processing Plants

Miti, Wilson January 2014 (has links)
Copper processing plants involved in smelting, electro-refining and electro-winning are heat-intensive undertakings that provide extensive challenges for attainment of high energy efficiency. Literature has shown that most of these plants, especially smelters, operate at low overall energy efficiency due to the seemingly complex energy scenario where heat and electricity as forms of energy are treated distinctively from each other. Many copper processing plants have not yet explored both available and emerging waste heat recovery technologies hence remain operating at lower energy efficiencies. In the copper processing plants under study in particular the Nchanga tailings leach plant (TLP), plant operators hinted that some of the processes that ought to operate in heated environments operate at ambient temperatures because of lack of a heating mechanism. The project discusses possible heating mechanisms from available local resources and applicable technologies. As the competing options for providing the required heat at the Nchanga TLP present different carbon emission scenarios, the carbon emissions associated to the recommended installations shall be quantified against a suitable baseline. Flue gas waste heat from the nearby Nchanga smelter has been taken as the available local energy source on which the applicable heating scenarios at TLP are analyzed. The project analyzed waste heat scenarios for three furnaces at Nchanga smelter where it has been established that flue gases from the furnaces contain 37.31 MW of waste heat. Analysis for channeling the waste heat into heat recovery steam generators gave the steam turbine power generation potential of 7.06 MW. The project also demonstrated how energy efficiency undertakings can be used as a driver for carbon emission reduction measures and for participation to the available carbon trading mechanisms such as CDM. Selection of suitable baseline scenarios revealed a lot of potential for carbon finance undertakings in the three case study plants. At the Nchanga smelter, the 7.06 MW power generation capacity has an associated potential of 61,820 tCO2/year emission reductions that can be monetized through the available carbon trading markets. The research established that Nchanga TLP has a heating demand of 10.87MW. If this heating demand was to be met by using the smelter waste heat, the undertaking can be taken as CDM activity or other carbon trading platform with an associated potential of 95,183 tCO2/year.
163

Kamna v konceptu moderního vytápění / The stove in the concept of modern heating

Koutecký, Jan January 2012 (has links)
Thesis deals with stoves, considering them as the main source of heating. The theoretical part is focused on practical and theoretical stove designing and burnnig proces. The designing addresses three of the countless variations on the koncept of modern stove heating. Each variant is unique in its technical and design way of solution. Experiment affects the properties hypokaust stove.
164

SOFT-TEMPLATING SYNTHESIS OF MESOPOROUS SILICA-BASED MATERIALS FOR ENVIRONMENTAL APPLICATIONS

Gunathilake, Chamila Asanka 19 April 2017 (has links)
No description available.
165

Kondenzační technika a odvody spalin / Condensing technology and flue gas

Müller, Jan January 2014 (has links)
This thesis is developed as a proposal for heating for a primary school and kindergarten in the region of Brno-countryside. For the insulated building, a combination of heating and air-conditioning is proposed. The concept is designed so that the air-conditioning preheats the exterior air and the heating system warms the incoming air to a comfortable temperature. For the required thermal performance, sources of heat (for gas and pellets) and a layout solution for the boiler room is designed. Drainage of combustion products is proposed for both solutions. The project solution is per the extent of the construction permit. The theoretical part is linked with the practical part through the condensation boilers, their function and division, and drainage of combustion products. The experiment for the given topic was conducted on the drainage of combustion products. The pressure loss of the reverse knob was determined in relation to the flow rate of air in the condensation boilers as this loss is essential in assessing the drainage of combustion products.
166

Distribuční soustava Kypru - realizovatelnost obnovitelných zdrojů a přenos energie / Distribution system of Cyprus - feasibility of renewable energy sources and transfer of energy

Šimonová, Lucie January 2011 (has links)
Until a few decades ago few people could imagine that the photovoltaic, solar thermal and other power based on renewable resources, will become a reality. Today people from all over the world on the contrary try at full blast derive benefit from of all possible available source. Using sunlight as a source of energy is first enforced only for small devices such as calculators for charging the battery, but now we are able to produced energy from the sun to supply people around the world. Of course it is not possible supply consumer sector plus firm only from performances renewable power supply. Therefore endeavour is derive benefit from classical energy production at the same time with others power supply. The basic components of photovoltaic and solar thermal power are panels. The panels are made of different materials in different shapes and sizes. During production, the resulting effect looks in addition to costs associated with production. For photovoltaic and solar thermal power plant requires sufficient sunlight. The sunshine has biggest intensity on south of ours planets. Therefore endeavour is build lump these power station just in stand with bigger intensity sunshine. One of them is just Cyprus, too.

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