Sökning: "bubbling"

Visar resultat 11 - 15 av 51 avhandlingar innehållade ordet bubbling.

  1. 11. Fluidized-Bed Reactor Systems for Chemical-Looping Combustion with Inherent Separation of CO2

    Författare :Eva Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical-Looping Combustion; Interconnected Fluidized Beds; Carbon Dioxide Capture;

    Sammanfattning : In chemical-looping combustion (CLC) a gaseous fuel can be burnt with inherent separation of carbon dioxide. The system consists of two reactors, a fuel reactor and an air reactor and an oxygen-carrier in the form of metal oxide particles that transports oxygen from the air to the fuel. LÄS MER

  3. 12. Fluid Dynamics and Erosion in a Fluidized Bed for Energy Production. A Numerical and Experimental Study

    Författare :Klas Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; experimental validation; multiphase flow; energy; two-fluid model; environment;

    Sammanfattning : This thesis presents an experimental and a numerical investigation of fluid dynamics and erosion of heat transfer tubes in fluidized beds for energy conversion. The objective is to obtain recommendations for suitable models that can be used to predict the fluid dynamics and material wastage of heat exchanger tubes in fluidized beds. LÄS MER

  4. 13. Layer formation on quartz particles during fluidized bed combustion/gasification of woody biomass

    Författare :Hanbing He; Christoffer Boman; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Sammanfattning : The formation of sticky layers on bed particles has been considered as a prerequisite for bed agglomeration in fluidized bed combustion and gasification of woody fuels. In addition, the layer formed makes the bed particle less resistant against fragmentation. The fragments from quartz particles can result in deposition. LÄS MER

  5. 14. Fabrication and characterization of graphene-superconductor devices

    Författare :Niclas Lindvall; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Graphene; Atomic force microscopy; Aharonov-Bohm effect; Weak localization; Bolometer; Chemical vapor deposition; Synthesis; Mechanical cleaning;

    Sammanfattning : Graphene is the first single-atom-thick two-dimensional material and exhibits a large set of interesting properties. This thesis consists of two parts. The first regards the growth of large-area graphene using chemical vapor deposition (CVD). LÄS MER

  7. 15. The effect of surface morphology on bed particle layer characteristics in fluidized bed combustion and gasification of woody biomass

    Författare :Ali Valizadeh; Marcus Öhman; Mikael Thyrel; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energy Engineering; Energiteknik;

    Sammanfattning : A critical process phenomenon in fluidized bed combustion and gasification is the bed particle layer formation which might be problematic in cases where it instigates bed agglomeration and bed material deposition or could improve the process performance in cases where it has a positive effect on tar reduction in biomass gasification. The interactions between ash forming matter for a wide variety of wood-derived fuels with different types of bed materials in fluidized bed combustion and gasification have been profusely studied, and the underlying mechanism of bed particle layer formation has been suggested. LÄS MER