Upgrading of coal using cryogenic HGMS

Abstract

High gradient magnetic separation (HGMS) is a promising technique for upgrading coal. Preliminary results using liquid nitrogen as carrier fluid in HGMS equipment are shown. The reduction of ash and sulfur content of pulverized coal upon processing with cryogenic HGMS is comparable to earlier results using other transport fluids such as water. The expected increase of capacity of cryogenic HGMS, compared to conventional HGMS, is experimentally confirmed. Cryogenic HGMS, if done at liquid natural gas (LNG) terminals, may well be a new incentive for the commerical application of HGMS for coal cleaning.