| Common wet density separation processes require large amounts of water, expensive wastewater cleanup, and do not effectively recover fine particles. A circulating fluidized bed riser system was developed as an exploratory system for dry separation by density that will eliminate many problems associated with wet separation. The system sends an air-solid mixture through a vertical riser. The flow pattern in the riser, established by varying gas velocity (Uo) and mass flux (Jp), allowed dense particles to collect at the bottom of the riser while less dense particles were collected through the riser exit at the top. The system was developed with many variables used to determine the most effective system geometry for separation. The system was capable of separating 83% of the dense particles and only 1.3% of the less dense particles from the mixture. The separation quality can be adjusted by altering Uo, Jp, or the system geometry. |
