| The U.S. Department of Energy has determined that more than five billion tons of coal fines are stored in various impoundments across the country. Obviously, the short-term solution for these problems is to utilize the coal fines currently being discarded, while the long-term approach remains in substantial reclamation of the coal impoundments.; The primary objective of this research was to develop a novel dewatering technique for handling fine fractions of coal. Using existing commercially available briquetting equipment and a binding agent, the process investigates the potential to produce robust fine coal briquettes that have a low moisture content. The expertise of a commercial briquetting machine manufacturer and empirical data obtained from the research were utilized to develop an expert system that controls the briquetting machine.; Several modifications were implemented to the briquetting machine, which enhanced the dewatering efficiency of the feed material. As a result, robust fine coal briquettes with acceptable low moisture content, were produced. Through various studies, basic relationships between several operating variables, including roll speed, briquetting form pressure and feed screw speed, were established. The study that focused on the use of a solvent in the coal/binder mixture suggested that at low binder concentration the addition of a solvent can effectively deliver the binder onto the fine coal surface, and thus improve briquette characteristics. Overall, these studies have provided further insights on this conceptually simple, yet complicated process.; As seen in this study, this process has the potential to be a highly efficient yet low cost addition to coal preparation plants used in the mining industry. Furthermore, the success of this process can also play a significant part in fine coal reconstitution from old coal impoundments. Besides recovering a valuable energy source, this process provides an opportunity to accelerate the cleanup of thousands of coal impoundments across the country, which has been the subject of significant criticism of the mining industry for generations. |
