Development of Upgrading Method of Low Rank Coal for Its Utilization in Cokemaking

Abstract

Japanese steel industries, which are importing all coal resources required, are facing the necessity of increasing usable coal resources. They are to increase the kinds and amounts of usable coal and to develop the technologies for upgrading low rank coals such as subbituminous coal and brown coal as substitutes. In this work we have developed methods for upgrading brown coal. The methods involve the fractionation of brown coal using sequential thermal solvent extraction, dewatering and upgrading of brown coal using hydrothermal treatment, and co-pyrolysis of upgraded brown coal and plastic derived wax. It is shown that these methods enable to produce binders for cokemaking and substitute of slightly/noncaking coal.