An Aspect on the Magnetic Properties.of Coals

Abstract

Four coals were separated into portions of different density by the float-and-sink method.The magnetic susceptibility, density, ultimate analysis, proximate analysis and calorific value of each portion were determined and compared.For each coal sample the susceptibility showed approximately the linear relationship with the ash content.Therefore, the ash content may be estimated from the susceptibility measurements without direct determination.The Wiedemann's law on magnetic susceptibility appeared to be valid for coal and further the conditions of ash and molecules in coal were discussed.