Avancerad sökning

Visar resultat 1 - 5 av 309 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Deposit-feeding in benthic macrofauna : Tracer studies from the Baltic Sea

    Författare :Lars Byrén; Ragnar Elmgren; Lisa A. Levin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Deposit-feeding; Macrofauna; Baltic Sea; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : A low content of organic matter, which is largely refractory in nature, is characteristic of most sediments, meaning that aquatic deposit-feeders live on a very poor food source. The food is derived mainly from sedimenting phytodetritus, and in temperate waters like the Baltic Sea, from seasonal phytoplankton blooms. LÄS MER

  3. 2. 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

  4. 3. Fouling in biomass fired boilers

    Författare :Jan Sandberg; Rebei Bel Fdhila; Erik Dahlqvist; Anders Nordin; Mälardalens högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fouling; deposit; boiler; biomass; simulations; Thermal energy engineering; Termisk energiteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

    Sammanfattning : In order to reduce the discharge of the greenhouse gas CO2, the use of biomass is nowadays promoted as fuel in boilers. Compared to boilers fired with coal and oil the biomass-fired boilers have more complications related to both fouling and corrosion on the heat transfer surfaces. LÄS MER

  5. 4. Ash Behavior in Fluidized-Bed Combustion and Gasification of Biomass and Waste Fuels : Experimental and Modeling Approach

    Författare :Farzad Moradian; Högskolan i Borås; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluidized-bed; combustion; gasification; waste-derived fuels; biomass; ash-related problems; deposit; fouling; slagging; bed agglomeration; thermodynamic equilibrium modeling;

    Sammanfattning : Over the past few decades, a growing interest in the thermal conversion of alternative fuels such as biomass and waste-derived fuels has been observed among the energy-producing companies. Apart from meeting the increasing demand for sustainable heat and power production, other advantages such as reducing global warming and ameliorating landfilling issues have been identified. LÄS MER

  7. 5. Alkali Induced Corrosion of 304L, The Influence of Potassium Salts and Water Vapour

    Författare :Jesper Pettersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 304L; Alkali; Breakaway Corrosion; KCl; Oxidation; Deposit;

    Sammanfattning : This work investigates the influence of alkali salts on the oxidation of304-type (Fe18Cr10Ni) austenitic stainless steel in laboratory and fieldexposures. Stainless steel coupons were exposed isothermally inlaboratory furnaces at 400-600 °C in 5% O2 and 5% O2 + 40% H2O.Thermobalance exposures were also performed. LÄS MER