Optimizing Dewatering-Introducing a new Dewaterability Testing Procedure

Ongoing research into causes in dewaterability losses required a method to conduct dewatering testing with properties that were difficult to find in one unit. The method needed to be bench scale, simple, robust, mobile, utilize equipment commonly found in wastewater treatment plants, and produce dewatered cake. This lead to the design of a bench scale pneumatic press that functions similar to a belt or plate filter press with respect to the dewatering forces. The press is small enough to fit in a trunk of a car and weighs roughly 100 lb assembled. The design is simple and the main parts can be fabricated locally and for larger utilities even in-house. The prototype (Figure 2-4) has been in use for nearly a year and hundreds of tests have been conducted. This included extensive testing of the method itself to establish the protocol, confirm its functionality and reproducibility of the results. The available variables were maximum pressure, duration, and rate of pressure increase.