ABSTRACT
By the introduction of a water-insoluble flocculant, coal particles can be agglomerated even in a liquid slurry. Under appropriate shear conditions and assuming that the gangue materials are liberated, this process will tend to reject gangue materials from the coal. This process is known as selective agglomeration, which forms a size-enlarged coal product that can be easily separated from the gangue material. While the final separation quality is on par with froth flotation, selective agglomeration is useful for rejecting additional water from the coal. This chapter discusses the basic principles of selective agglomeration, along with a careful overview of the many process variables which influence the process. Unlike selective flocculation, selective agglomeration has seen significant industrial use and development, of which a brief history is provided. The primary limitation of selective agglomeration is a high reagent usage.
