Effect of sonication for in-situ stainless steel leaf filtration

Abstract

The application of ultrasound wave fields in the filtration and separation technology has been identified as a new and clean technology and as an alternative to the classical cleaning processes. Fouling phenomena is a major bottleneck in this separation technology, as expected in the industrial application of such finely porous media. As the filtration process continues, the concentration of solute keeps building up on the filter surface to form a filter cake. This results in a continuous decline of the flux. A number of methods are reported in preventing the fouling phenomena. In this paper, the effect of intermittent application of ultrasound wave fields (sonication) on the filtration of Refined Bleached Deodorised (RBD) oil suspension will be presented. The application of ultrasound field is projected to enhance the filtration rate by reducing the thickness of the filter cake formed on the surface of the filtering medium. The main mechanism which is expected to dominate in reducing the thickness of the filter cake is the cavitation phenomenon. In carrying out the study, parameters affecting the performance of the sonicated filtration also will be presented. Among the parameters of concern is the sonication cycle time. An average flux is measured in each experiment as an indication of effectiveness of this method in reducing the filter fouling. In all cases, the application of ultrasound for filtration and separation processes has been successful by reducing the flux decline at different variables.