On the solvent‐induced swelling of low‐rank coals

Abstract Swelling of low rank coals due to solvent contact is measured for a suite of such coals from different sources. The method is a simple one: the pouring of solvent on to samples of the coal in glass tubes and measurements of coal height before and after pouring on the solvent. Correlations between swelling and coal properties are discussed, and for one of the coals a ‘swelling spectrum’, displaying swelling as a function of solvent solubility parameter, is presented.