Measurement of adhesion strengths and energy between calcium carbonate cake and filter cloth
Abstract
Various devices in liquid-solid separation require mechanical cake discharge using different technologies. An incomplete cake discharge causes yield losses, cycle time increase, irregular cake formation, high mechanical constraints which decrease medium life time, excess consumption of cleaning liquors... Currently, cake discharge is only assessed qualitatively by observations of filter cloth after discharge or quantitatively by weighing recovered solids. A prototype has been developed to carry out reliable and repeatable measurements by removing filter cloth from filter cake by shearing. This study presents results of experiments performed with calcium carbonate (which forms sticky cakes) and discusses the conditions of cake formation and cake detachment from filter cloth. It highlights the role of two main parameters: filter cloth characteristics and pressure.