Investigation of the deswelling characteristics of Illinois No. 6 coal by nuclear magnetic resonance imaging (NMRI) and NMR techniques

摘要

NMRI can observe the internal and external physical structural changes of a sample as well as the solvent penetration process without physical handing. Although the spatial resolution achievable in NMRI of coal samples is only 20--40 (mu)m swelling of coal can be measured because a polar solvent expands the coal to almost twice its original volume. NMR can also monitor the change of solvent concentration in a swollen coal (by integrating the peak areas of the NMR spectra), and can also examine solvent mobility (by measuring spin-lattice and spin-spin relaxation times). This paper reports results on application of NMR and NMRI for study of solvent induced-deswelling in an Illinois No. 6 coal.