Sökning: "CFB boiler"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden CFB boiler.

  1. 1. Co-firing animal waste, sludge, residue wood, peat and forest fuels in a 50MWth CFB boiler : ash transformation, availability and process improvements

    Författare :Henrik Hagman; Dan Boström; Rainer Backman; Anders Nordin; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Co-combustion; animal waste; peat; waste wood; forest residues; industrial sludge; limestone; CFB boiler; ash transformation; corrosion; erosion; ash and deposit characteristics; deposit buildup; boiler failures; availability; sulfation; boiler design; boiler conversion; waste derived fuels; large scale; Samförbränning; animaliskt avfall; torv; returträ; skogsbränsle; reningsslam; askomvandling; korrotion; erosion; ask- och beläggnings-karaktäristik; beläggningstillväxt; tillgänglighet; sulfatisering; panndesign; pannkonvertering; avfallsderiverade bränslen; storskalig;

    Sammanfattning : The direct variable costs for heat and electricity production based on solid biomass fuel combustion is approximately 3-5 times lower than the costs in a fossil fuel-oil based boiler in Sweden. In addition waste derived biomass fuels are typically much cheaper than biomass not classified as waste. LÄS MER

  3. 2. Co-firing complex biomass in a CFB boiler : ash transformation, corrosion control and materials selection

    Författare :Henrik Hagman; Dan Boström; Rainer Backman; Mats Lundberg; Lars-Erik Åmand; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ash transformation; process control; equilibrium calculations; boiler availability; failures; alloy selection; alloy degradation; vortex finder VF ; service life estimation; sulfation; chloridation; high temperature corrosion; biomass; waste derived fuels; forest residues; RDF; Biomal; slaughterhouse waste; peat; waste wood; industrial waste water treatment sludge; HAD; RSMT; Alloy 253MA; Alloy 310S; Alloy 800H HT; Alloy DS; Alloy 600;

    Sammanfattning : The effects of greenhouse gas net emissions on global warming, stricter legislation on waste handling, and the pursuit of ever cheaper heat- and power production are all important factors driving the introduction of complex fuels in incineration plants. However - without fundamental knowledge regarding ash transformation, corrosion control, and materials selection – this introduction of potentially economically and environmentally beneficial fuels, might instead cause economic loss and environmentally adverse effects. LÄS MER

  4. 3. Deposit Induced Corrosion in Biofuel Combustion

    Författare :Petter Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ferritic steel; high temperature corrosion; superheater; waste combustion; CFB; biofuel boiler; waterwall; alkali chloride; deposit induced corrosion; chromate; nickel-based alloy; austenitic steel; martensitic steel; waste boiler;

    Sammanfattning : Deposit induced corrosion is one of the main mechanisms for attack on heat exchangers in biofuel boilers. This severe corrosion decreases the obtainable steam temperature in boilers, thereby the efficiency in production of electricity is reduced. Deposit formation from the gas on superheater tubes are is generally referred to as fouling. LÄS MER

  5. 4. Gas Mixing in a Circulating Fluidised Bed Boiler

    Författare :Johan Sternéus; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circulating fluidized bed; gas mixing; tracer; boiler; dispersion; scaling; turbulence; two-phase flow; fluidization;

    Sammanfattning : The present thesis is a study on the gas-mixing behaviour in a circulating fluidised bed (CFB) boiler. The aim is to describe how gas is spread in different regions of a CFB furnace and to explain variations in the mixing rate under different operating conditions. LÄS MER

  7. 5. Investigation of Solids Distribution and External Solids Flux in a Circulating Fluidized Bed Boiler

    Författare :Elin Edvardsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; external solids flux; recirculation rate; solids distribution; CFB boiler; co-combustion;

    Sammanfattning : This work concentrates on two issues regarding combustion in circulating fluidized bed (CFB) boilers. Firstly, the impact of co-combustion of coal with sewage sludge on ash flows, bed material and gas concentrations in a CFB boiler is studied. LÄS MER