Advances in the adsorptive particulate flotation process

Abstract

The removal of contaminants from liquid effluents by the adsorptive particulate flotation (APF) process, including new adsorbents and flotation devices, are reported. Herein, contaminants are adsorbed (and/or absorbed) onto the surface of a particulate carrier and both are separated attached to rising bubbles. The adsorbents were coal, charcoal, coal beneficiation tailings, modified Brazilian smectites and barite. Emulsified oils in water, dyes and metal ions present in synthetic and industrial effluents were successfully removed using various carrier and DAF, induced air flotation, IAF or jet flotation for the separation of the loaded carrier. Process efficiency was found to be a function of the carrier/contaminant mass ratio, size distribution of the carrier and system hydrodynamics. Results and mechanisms involved are discussed in terms of adsorption and flotation phenomena.