Study of a wedge zone simulation equipment and characterization of the cakes obtained from the filtration of two suspensions

Belt filter press is one of the equipment used for solid-liquid filtration. To achieve a good filtration; the cake has to be stable: this means that a liquid filtrate has to be obtained and/or the cake does not have to spread too much during filtration, depending whether the filtrate or the solid is the product of interest. Experiments were carried out on an anthracite coal slurry and on a metal suspension varying the wedge zone pressure in a lab-scale equipment. First, measurements on the load applied by the wedge zone simulation equipment were performed and they led to the discovery of a failure in the equipment; then experiments on the two suspensions were carried out. The amount of filtrates, the dry solid content and the porosity of the cakes and the dimensions of the cake were measured. At the end a model to evaluate the shape of the cake was proposed and a material balance was carried out.