An Experimental Study of Clay Binders in Fine Coal Froth Flotation

摘要

It is well known that the clay particles in fine coal severely impede the froth flotation process. This is mainly due to the presence of tiny size (< 1mm in most cases) or huge specific surface area of clay particles that result in slime coating on the coal surface. Use of clay binders is a promising method for enhancing coal flotation performance since it can agglomerate clay particles to enlarge their apparent size, reduce their surface area and reagent adsorption, remove coal surface slime coating to restore its hydrophobicity and minimize the non-selective hydraulic entrainment. rnAn experimental laboratory study was conducted to evaluate the performance of several novel clay binders developed by Georgia-Pacific Chemicals, LLC in a metallurgical fine coal froth flotation process. The clay binders are a group of special, low molecular weight polymers produced under acidic conditions with different components and structures, different degrees of functionalization, and different molecular weights and crosslink densities. Process variables such as clay binder dosage and conditioning time, collector and frother dosage, and conditioning intensity were investigated for their effects on clay binder performance. Experimental results have shown that clay binders significantly enhanced flotation selectivity, increasing clean coal yield by up to 15–30%, depending on the flotation conditions.