Rapid microwave pyrolysis of coal

A detailed study of the microwave pyrolysis of the Moroccan (Youssoufia) rock phosphate

“…This result suggests that the residue does not contribute to the heating. This is confirmed by other works on organic or mineral solids [56,[72][73][74], which showed that the residues obtained after pyrolysis do not present neither a dielectric nor an ionic character [44].…”

Microwave pyrolysis of sewage sludge: analysis of the gas fraction

“…These materials are, in general, poor receptors of microwave energy, so they cannot be heated directly up to the high temperatures usually required to achieve total pyrolysis. However, microwave-induced pyrolysis is possible, if the raw material is mixed with an effective receptor of microwave energy such as carbon [21][22][23][24] or certain metal oxides [19,20]. The use of microwave-assisted processes in sewage sludge handling or treatment is not entirely new.…”

“…Thus, processes such as the drying and heating of minerals and inorganic products, the carbothermic reduction of metal oxides, mineral leaching, coal liquefaction, the production of active carbon, spent carbon regeneration and the surface chemistry modification of carbons are only a few examples of the different processes currently being used or investigated [8][9][10][11][12][13][14][15][16]. Microwave heating has also been considered as an alternative for carrying out the pyrolysis of biomass [17,18], coal [19,20], oil shales [21,22], and various organic wastes [23,24]. These materials are, in general, poor receptors of microwave energy, so they cannot be heated directly up to the high temperatures usually required to achieve total pyrolysis.…”

Influence of Additives on Cokemaking from a Semi-soft Coking Coal during Microwave Heating

“…8) Various researchers have reported on utilizing susceptors to enhance certain metallurgical reactions during microwave heating. Substances such as CuO, V2O5, WO3, Fe2O3 and even metallurgical coke were utilized by Monsef-Mirzai and co-workers 9,10) as microwave susceptors. Other substances included for example different chars.…”

“…The addition of a proportion of the susceptor enhances both the heating rate in a microwave field, due to a very rapid energy transfer into the material being heated, and also the rate of reduction of the susceptor for the case where the susceptor is a metal oxide. 13,21) Other advantages of microwave heating are that the susceptor particles would heat simultaneously, thus reducing heat transfer problems, 10) and rapid dissipation of energy and the high energy densities capable in small volumes allows equipment to be significantly smaller in physical size than conventional systems. 21) The aim of this study was to i) determine dielectric properties of granular Waterberg semi-soft coking coal (sscc) as well as fines from ferro-alloys and their ores, ii) followed by investigating coke formation from admixtures.…”