method for drying of fine coal and processing high-quality coke

摘要

Fine coal, unsuitable as such for conversion to high-grade coke is prepd. by drying with a hot oxygen-free gas, pref. superheated steam. It is subsequently mixed with a binder and compacted by pressure, e.g. into briquettes, by usual methods before coking. Pref. the whole drying and dust removal process is carried out in a closed system under pressure to prevent entry of air. Steam for the drying coal is released through a pressure valve. The mixing equipment in which binder is incorporated is also maintained under pressure by an oxygen-free gas. Washed fine coal can be dewatered and dried without self-ignition as occurs when heated in air at over 393 degrees K.