00/00626 Adaptation of a briquetting machine for the dewatering and consolidation of fine coal

Abstract

The Illinois Clean Coal Institute (ICCI) developed a new coal preparation method to recover the high heating value Illinois coal, containing high amounts of sulfur (in the form of pyrite). Unfortunately, the new cleaning method, consisting of fine grinding the coal to liberate mineral matter, such as the pyrite, produced large amounts of high moisture ultra-fine coal. One of the economically viable alternatives to dewater and recover the fine coal was to adapt a commercially available machine. A roll briquetting machine was chosen for the dual purpose of dewatering and consolidating fine coal. Preliminary results indicated that robust briquettes with low moisture content could be produced under the current configuration. However, two areas of concern were realized during the pilot-scale experiments. First, the arching and caking problems resulted in inconsistent feeding of material. Second, back drainage into the feed hopper resulted in varying the feed moisture. Therefore, to effectively utilize the briquetting machine to dewater fine coal, appropriate mechanical modifications were needed. Design changes were conducted on the feed area of the machine, which resulted in the elimination of the problems encountered. Briquettes with consistent low moisture content and adequate strength characteristics could now be produced under the new configurationmore » of the briquetting machine.« less