Development and scale-up of a gas-promoted oil agglomeration process for coal beneficiation

The important characteristics of agas-promoted oil agglomeration process fo r cleaning coal particles in an aqueous suspension were determined. Numerou s agglomeration tests with scale-model mixing systems of different sizes wi th controlled amounts of air were conducted. The tests were conducted on hi gh- and medium-volatile bituminous coals using either i-octane or hexadecan e as an oily agglomerant. The performance of the system was characterized b y employing the minimum time required to produce spherical agglomerates (t( E)), the mean agglomerate diameter (d(p)), coal recovery and product ash co ntent. Among these parameters, tE Was found the most useful. It is a key pa rameter in the scale-tip of an agglomeration mixing system. This parameter was found to depend on a number of system and operating variables. By contr olling these variables and conducting further agglomeration tests with mixi ng systems that varied in size, an appropriate size scale-lip rule was esta blished.