Experiment on adhesion and removal of suspended particle in liquid by bubble - Investigation on removal rate constant at initial stage

It is widely recognized that inclusions in steel cause defects to the products. Therefore, it is important to remove inclusions from liquid steel. The attachment and removal by bubble flotation is expected as one of promising techniques for inclusion removal in liquid steel. The process of particle removal by bubbles is influenced by various factors, including the liquid flow, particle diameter, bubble size. The present work is intended to investigate experimentally the effects of some factors such as particle diameter, gas flow rate and agitation speed to particle removal rate. In this study, water model experiments on bubble flotation have been done under turbulent flow condition using a mechanically agitated vessel. It was confirmed that the change in particle concentration of suspended liquid with time shows first order kinetics until 4 minutes in the initial stage. Furthermore, it was found that the particle removal rate has increased with increasing particle diameter, gas flow rate and agitation speed.