Depth filtration, adsorption and ion exchange are key unit operations in water treatment. CE 581 enables these three operations to be demonstrated.

The raw water is pumped from above into a gravel filter and then routed into a sand filter. In the process, suspended solids are removed from the raw water. The filtered water then flows into the second treatment stage. There dissolved substances are removed by adsorption on aluminium oxide and on activated carbon. Then the water passes on to the third treatment stage. In this stage unwanted ions are removed from the water by ion exchange. First the water is softened by cation exchange. The water is then desalinated in a mixed bed ion exchanger containing cation and anion exchangers.

The separate supply unit includes pumps and tanks for the raw water and treated water. The raw water tank can be aerated. This ensures the raw water is mixed through. It also enables dissolved substances (such as iron) to be precipitated so as to then filter them. A connection to backwash the sand filters is provided.

The flow rate, temperature, conductivity, differential pressure and system pressure are measured. Samples can be taken at all relevant points.

The experimental plant is equipped with a comprehensive range of functions for measurement, control and operation that are controlled by a PLC. A touch panel displays the measured values and operating states and can be used to control the plant. At the same time, the measured values can be transmitted directly to a PC via USB where they can be analysed with the software.