Textural properties in density-separated coal fractions

The results presented in this work are part of a more extensive research pr ogramme aimed at assessing the impact of coal porous structure on density-b ased process evaluation and modelling. The coal samples used were obtained from two different density-based cleaning processes, a Vorsyl dense medium separator for treating an anthracite (TW) with a size fraction of 0.5-8.0 m m and a spiral concentrator for heating a bituminous coal (DH) with a size of less than 2 mm. Textural characterisation of the samples was carried out by measuring hue (helium) and apparent (mercury) densities and mercury por osimetry up to a maximum pressure of 200 MPa. Adsorption isotherms in CO2 a t 273 K were also determined for both coal series. In the case of the bitum inous coal series a linear relationship between porosity and ash level was found. This may have important implications if coal porosity and/or textura l parameters need to be incorporated into new density-based simulation mode ls. (C) 1999 Elsevier Science Ltd. All rights reserved.