Gasification and structural behaviour of different carbon sources and resultant chars from rapid devolatilization for HIsarna alternative ironmaking process

Reduction of FeO in Molten Slag by Solid Carbonaceous Materials for HIsarna Alternative Ironmaking Process

“…Gas diffusion in the halo can also be considered to have an influence on the rate-controlling step at the first stage of the reaction. In the authors' previous findings, [36] TC was shown to be less reactive with CO 2 while CC was the most reactive material. From this, it can be assumed that the chemical reaction at the gas-carbon interface (Eq.…”

“…With regard to the obvious difference in the reduction degree by different char particles in the initial stage (the first 500 seconds in Figure 5), this may be attributed to the difference in their physical and chemical properties of different char particles such as crystalline structure, particle surface roughness, and ash content, which ultimately control the slag interaction with solid carbon particle and governing carbon reactivity. [36] Biomass samples (CC and BGC) have non-compact, low dense fibrous structure, and capillaries from the parent materials are still present, while TC char particles are very compact with more spherical shape and smooth and non-porous surface. [36] The structure and capillaries on biomass char surface contribute to the relatively larger specific surface for interaction.…”

“…[36] Biomass samples (CC and BGC) have non-compact, low dense fibrous structure, and capillaries from the parent materials are still present, while TC char particles are very compact with more spherical shape and smooth and non-porous surface. [36] The structure and capillaries on biomass char surface contribute to the relatively larger specific surface for interaction. The authors' previous study for TC and CC confirms that CC contains disordered graphite structure and is more amorphous compared to TC which will enhance the reactivity of CC.…”

“…This phenomenon is due to the higher reactivity of CC chars compared to the other two selected carbons. [36] This indicates that the carbon type can have a great influence on the rate of reaction, and chemical reaction is the controlling mechanism for the first stage. Regardless of the carbon type used, the conversion degree is more similar at a given temperature for reactions at the second stage.…”

Evaluation of Physical and Chemical Properties of Residue from Gasification of Biomass Wastes

“…The surface area of this sample obtained the highest value under 1000 • C. All char samples indicated similarities with the shapes to the parent materials. The release of volatile matter during gasification did not involve damage to the structure of the char particles due to the natural porosity of the biomass [59]. On the other hand, rapid release of volatile compounds at high temperature leads to the softening of the solid matrix or a coverage of the pores by fractional melt formation [60], which then causes clogging of the pores.…”