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Visar resultat 1 - 5 av 18 avhandlingar som matchar ovanstående sökkriterier.

1. 1. From torrefaction to gasification : Pilot scale studies for upgrading of biomass

   Författare :Martin Strandberg; Anders Nordin; Linda Pommer; Jaap Kiel; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Torrefaction; biomass; pilot scale; continuous reactor; grindability; entrained flow gasification; degree of torrefaction; biomass powder;

   Sammanfattning : Increasing the share of biomass, preferably by replacing fossil fuels, is one way to mitigate the present climate change. Fossil coal can be directly replaced by co-combustion of coal and biomass and fossil engine fuels (gasoline and diesel) could potentially partly be replaced by synthetic renewable fuels produced via entrained flow gasification of biomass. LÄS MER

3. 2. Volumetric combustion of torrefied biomass for large percentage biomass co-firing up to 100% fuel switch

   Författare :Jun Li; Weihong Yang; Günter Scheffknecht; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biomass; co-firing; torrefaction; torrefaction degree; kinetics; volumetric combustion; fuel switch;

   Sammanfattning : The co-firing of biomass and coal plays an important role in increasing the biomass power capacity and reducing greenhouse gas (GHG) emissions. The challenges of the large percentage biomass co-firing (over 20% on energy basis) in existing pulverized coal boilers are keeping the same steam parameters and having a high boiler efficiency and a stable operating. LÄS MER

4. 3. Syngas production by integrating thermal conversion processes in an existing biorefinery

   Författare :Katarina Åberg; Anders Nordin; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biorefinery; biofuels; syngas; gasification; torrefaction; methane reforming; H2 CO ratio; system analysis; CO2 negativity;

   Sammanfattning : The use of carbon from fossil-based resources result in changes in the earth’s climate due to emissions of greenhouse gases. Biomass is the only renewable source of carbon that may be converted to transportation fuels and chemicals, markets now fully dominated by traditional oil supply. LÄS MER

5. 4. Dioxins and dioxin-like compounds in thermochemical conversion of biomass : formation, distribution and fingerprints

   Författare :Qiuju Gao; Stina Jansson; Bogdan Dlugogorski; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polychlorinated dibenzo-p-dioxins; polychlorinated dibenzofurans; polychlorinated naphthalenes; PCDD; PCDF; PCN; persistent organic pollutants; torrefaction; pyrolysis;

   Sammanfattning : In the transition to a sustainable energy supply there is an increasing need to use biomass for replacement of fossil fuel. A key challenge is to utilize biomass conversion technologies in an environmentally sound manner. LÄS MER

7. 5. Pretreatment and enzymatic saccharification of lignocellulose : formation and effects of pseudolignin

   Författare :Monica Normark; Leif Jönsson; Sandra Winestrand; Torbjörn Lestander; Wilfred Vermerris; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pretreatment; enzymatic saccharification; ionic liquid; torrefaction; pseudolignin; Analytical Chemistry; analytisk kemi;

   Sammanfattning : Production of advanced biofuels, green chemicals, and bio-based materials from renewable lignocellulosic biomass would contribute to decreased dependence on fossil resources and to sustainable development. The overall aim of the investigations was to explore how preprocessing and pretreatment technologies affected the chemical composition of cellulosic materials and their susceptibility to enzymatic saccharification, which is one of the major routes for biorefining of lignocellulose. LÄS MER