Visar resultat 1 - 5 av 21 avhandlingar innehållade ordet devolatilization.
1. Fast devolatilization of biomass : An experimental study using high-speed imaging, relevant for suspension firing technologies
Sammanfattning : We have performed experiments using imaging techniques in a flame-assisted, drop-tube reactor with optical access, to extract information relevant to the improvement of multi-particle devolatilization models. These models could be of interest for different suspension firing techniques, such as entrained flow biomass gasification, (EFBG) and oxyfuel combustion. LÄS MER
Sammanfattning : The aim of the current work was at development and validation of modeling tools for simulation of pulverised wood flames in furnaces and study how different factors influence on such flames. The numerical model involves different sub-models for the physo-chemical processes, such as, two-phase flow motion, drying, devolatilization and shrinkage of particles, the formation and oxidation of volatile, tar and char, turbulence-chemistry interaction, turbulence-radiation interaction, etc. LÄS MER
Sammanfattning : The steel industry is aiming to reduce CO2 emissions by different means; in the short-term, by replacing fossil coal with highly reactive carbonaceous material like bio-coal (pretreated biomass) and, in the longer term, by using hydrogen. The use of bio-coal as part of top charged briquettes also containing iron oxide has the potential to lower the thermal reserve zone temperature of the Blast furnace (BF) and, due to improved gas efficiency, thereby give a high replacement ratio to coke. LÄS MER
Sammanfattning : Heat and mass transfer to/from a single active particle in bubbling and circulating fluidized beds have been studied with application to fluidized bed combustion. A method of calculation of the heat and mass transfer coefficients in a bubbling fluidized bed (BFB) has been developed. LÄS MER
5. Fuel conversion and ash formation interactions : a thermochemical study on lignocellulosic biomass
Sammanfattning : Biomass is considered to be CO2 neutral, and to be able to reduce the dependency on fossil fuels the need for expanded and sustainable biomass feedstock is increasing. Ash-related problems are some of the most important aspects of this increasing use of new biomass assortments in thermal energy conversion systems. LÄS MER