Abstract

This article gives an overview of liquid filtration. Cake filtration is the most commonly used filtration in industry to separate solid particles from liquid streams. Depth filters are often used in a posttreatment step to polish liquids and remove particles to achieve a specific liquid purity. Brief descriptions are given on cake filtration and depth filtration theories along with a discussion on pretreatment of the slurry and posttreatment of the filter cake.

The theories described in this paper are useful to interpret experimental data and can help guide in the selection of equipment. The remainder of the article focuses on equipment types, equipment selection, and selected testing methods. There are many types of equipment for separating solids from liquid steams. Selection of the most appropriate equipment for a specific application can be difficult. Some guides are provided that help to narrow down the selection process.

Keywords: Surface filters; Deep bed; Washing; Solids; Cake dewatering; Pretreatment; Suspension; Magnetic separation; Pressure; Centrifugal filters; Vacuum filters