The growing demand for rare-earth elements and yttrium (REY) in modern technologies has resulted the systematic depletion of primary ores. For this reason, research is being conducted around world on alternative sources elements, e.g., possibilities recovering REY from coal waste or combustion. article presents results comprehensive tests fuel—hard coal, high-temperature HTA ash, fly bottom ash...

Thermal pretreatment or torrefaction of biomass under anoxic condition can produce an energy dense and consistent quality solid biomass fuel for combustion and co-firing applications. This paper investigates the fuel characteristics and grindability of pine chips and logging residues torrefied at temperatures ranging from 225 °C to 300 °C and 30 min residence time. Grinding performance of torre...

Coal and biomass pyrolysis and gasification has gained importance in the last few decades for synthetic fuel synthesis, which is a promising solution to the current energy crisis. Efficient fuel feed is necessary to the coal and biomass utilization processes. Common gasification systems employ large-scale slurry feeders to inject the fuel into the gasifier vessel. The presence of excess water i...

Since oxy-combustion is a relatively new technology, many problems associated with the behavior of coal in this novel combustion process still need to be solved. In particular, there is a lack of knowledge regarding the behavior of toxic trace elements, and there is a need to determine whether trace element distribution among the by-products and emissions to the environment, is comparable with ...

Selective flocculation has long been suggested as a method for the treatment of ultra-fine particles typical of which are those produced in a de-sliming process ahead of flotation. In this paper the results of the coal de-mineralization, using synthetic polyacrylamide polymers, are presented. A prescreening test on the suitability of the polymers using Run-Of-Mine (R.O.M.) coal and artificial m...

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Oxy-fuel combustion is a clean coal technology based on firing fuel in an enriched oxygen atmosphere to obtain a high CO2 concentration in the off-gases. This technology can be combined with the co-firing biomass and the use of blends of coal and biomass can compensate for the fact that the gas properties in the furnace in an oxycombustion process differ from the air-firing case (oxy-firing flu...