Chemistry and petrology of paired feed coal and combustion ash from anthracite-burning stoker boilers

The feed coal and corresponding ash from a series of stoker boilers burning Pennsylvania anthracite were investigated for their petrographic and chemical characteristics. The coals have low-S and moderate-ash contents with similar major oxide and minor element compositions. The volatile minor elements, such as Zn and As, decrease in concentration from the feed coal to the stoker ash (comparisons on the ash basis). The light rare earth elements (La through Sm) decrease in concentration relative to the heavy rare earth elements (Eu through Lu) from the coal ash to the stoker ash.