• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 135
  • 36
  • 16
  • 9
  • 7
  • 7
  • 5
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 235
  • 60
  • 59
  • 47
  • 29
  • 28
  • 24
  • 24
  • 23
  • 23
  • 21
  • 21
  • 21
  • 21
  • 19
  • 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.
191

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
192

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
193

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel January 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
194

Využití pěnoasfaltu v asfaltových směsích / Usage of foam bitumens in asphalt mixtures

Venclíková, Michaela January 2018 (has links)
In this diploma thesis there are described the issues use of foamed bitumen as binder in asphalt mixtures. The thesis is divided into two parts, theoretical and practical. The aim of theoretical part was to elaborate an overview of technologies, which allow to reduce the temperature during the production and laying of asphalt mixtures. The aim of the practical part was to compare the selected empirical and functional parameters of two types of asphalt mixtures produced in two variants, with hot bitumen and foamed bitumen. Attention was paid mainly to stiffness and low temperature parameters.
195

Využití technologie pěnoasfaltu / Usage of foam bitumen technology

Machel, Ondřej January 2019 (has links)
The diploma thesis deals with the production of warm mix asphalts, using the foam bitumen technology. The thesis is divided into theoretical and practical part. The theoretical part is focused on the basic division of roadway constructions, particularly on warm mix asphalts. The aim of the practical part was to find out whether the produced asphalt mixture retains its functional properties when the operating temperature is reduced. For this purpose, two asphalt mixtures of the ACO 11+ type at operating temperature of 150 °C and reduced operating temperature of 130 °C were made. Functional tests and empirical and functional tests were carried out on the produced asphalt mixtures and the extracted bitumen binders respectively. In the conclusion of the thesis, the results of the tests are mutually compared.
196

Asfaltové směsi s vyšší životností za použití R-materiálu / Bituminous mixtures with a higher lifetime using recycled asphalt

Stromecký, Roman January 2019 (has links)
This diploma thesis deals with a project of asphalt mixtures with high stiffness modulus using R-material. The theoretical part describes the characteristics of these mixtures in the Czech Republic and in Switzerland. Further this part deals with the use of R-material in the Czech Republic and chosen other countries of the world, it also deals with the ways of recycling roads. The theoretical part also deals with the testing methods used. In the practical part two new asphalt mixtures of the high stiffness modulus type with the addition of 25 % R-material are suggested. As a base for these two mixtures a mixture of the high stiffness modulus type, which was taken from an asphalt mixing plant, was used. Tests were run on the binders and several functional tests (stiffness modulus, fatigue resistance, low temperature qualities) wer done on the suggested asphalt mixtures and also the mixture taken from the mixing plant. Consequently, the results were compared. The conclusion of the thesis is devoted to modelling a construction of a road using the program LayEps, which verified if the suggested mixtures could reduce the thickness of roads.
197

Asfaltové směsi se zpěněným asfaltem / Foam asphalt mixtures

Brtníková, Tereza January 2020 (has links)
The diploma thesis is divided into theoretical and practical part. The theoretical part is mainly focused on methods for reducing the working temperature in the production of hot mix asphalt and the main reasons for this. Most attention is paid to the warm mix asphalt, mainly foam asphalt technology. In practical part are describes working procedures of individual tests on asphalt mixtures and recovered bitumen binders. The tests were performed on 3 types of ACO 11+, one was made with working temperature 160°C without foamed bitumen and the other two with foamed bitumen,one with working temperature 160°C and the second 140°C. Then were the results compared.
198

Využití fluxačních přísad pro úpravu vlastností asfaltových pojiv / Use of fluxing additives to modify the properties of asphalt binders

Šefránková, Radka January 2020 (has links)
The subject of the thesis is to describe the effect of fluxing additives on the behaviour of asphalt binders. Emphasis will be placed on changes in rheological properties of asphalt binders at intermediate temperatures, stability during aging and influence of fluxing agents on their low-temperature properties. Theoretical part will deal with the principle of asphalt binders aging and it will summarize knowledge about fluxing additives. Further, empirical and functional tests will be described in order to evaluate asphalt binders. In the practical part, all laboratory tests will be evaluated and the effects of two different fluxing additives will be compared.
199

Uplatnění pryžového granulátu v asfaltových pojivech a hutněných asfaltových směsích / Application of crumb rubber in bituminous binders and in bituminous mixtures

Dašek, Ondřej Unknown Date (has links)
Presented dissertation thesis is focused on the possibility of using the crumb rubber from waste tires for modification of paving grade bitumen. The resulting asphalt rubber can be used as an alternative to polymer modified bitumen in compacted bituminous mixtures. The theoretical part describes the rheological properties of asphalt binders and the history and today state of the art in the world and in the Czech Republic. The practical part of the work contains a description of the properties of chosen crumb rubbers and produced asphalt rubbers focused on their rheological properties and on change of these properties caused by the aging at high temperature. Subsequently, the chosen empirical and functional properties of bituminous mixtures with asphalt rubber are described. Laboratory properties of these mixtures were verified under real service conditions on 32 test sections. Based on the dissertation thesis results the preliminary technical specification of the Ministry of Transport (TP 148) and their following revision were approved. The conclusion of the work summarizes and highlights the results of the dissertation.
200

Využití R-materiálu v krytových vrstvách vozovek / Usage of recycled material in asphalt surface layers

Malá, Markéta January 2016 (has links)
Diploma thesis deals with adding R - material to the wearing asphalt courses, specifically to the SMA 11S. It has two parts – theoretical and practical. The theoretical part describes using R - material in the recycling of roads, different types of recycling and how is this problem handled in the Czech Republic, the practical part deals with the design of three kinds of asphalt mixtures with different added ratios of R – material, describing empirical and functional tests on the bitumen binder and the designed asphalt mixtures and the results of those tests.

Page generated in 0.0421 seconds