Analyses of Compressible Suspensions for an Effective Filtration and Deliquoring

Abstract

Cake filtration is frequently used in the industry to remove the majority of liquid from a suspension before the solids are dried in a thermal dryer. As the amount of liquid removed in the filtration step is an order of magnitude greater than the liquid removed during thermal drying, a slight improvement in the cake dryness from a filter can greatly reduce the duty and energy cost of the dryers. The most challenging issue in cake filtration is when a compressible material is encountered. High cake compressibility will not only slow down the filtration process, but also cause high moisture content in the final cake. Instead of pumping pressure, mechanical expression is the best deliquoring method when dealing with highly compressible cakes. Therefore, it is important for industrial users to recognize the degree of compressibility of the material being treated. In this work, a simple method is developed to estimate the cake compressibility from a single filtration run. This method provides a practical tool for engineers to understand the compressibility nature of the cake and select the right filtration/deliquoring strategy.

Keywords:

• Compressibility
• Industrial application
• Method
• Select
• Tool