Following a reconstruction period lasting 24 months, RHEWUM reopened its testing centre in November 2014 (Fig.). With the help of new equipment here at the site in Rem-scheid, classifying applications can be tested in very realistic conditions. With the newly installed test rigs, a wide range of different applications and conditions can be fast and flexibly replicated. For the tests, both closed-circuit and continuous plants are available for all commonly used RHEWUM dry screens. The new testing centre is also equipped with a classifier and cyclone test rig for fine to very fine separation as well as a closed circuit configuration for conducting wet screening tests.
The dimensioning of the test rigs enables simulation of the feed rates of industrial processes so that the plants can be reliably upscaled on the basis of the test findings. The continuous plant is used primarily for screening medium-quantity samples, i.e. around 10 kg to several 100 kg. The simple modular set-up enables uncomplicated and fast changeover of all RHEWUM screens. All screen types and dedusting are comfortably controlled by means of a central PLC system.
The closed-circuit plant is suitable for relatively large sample batches (>1 t). In addition it can be used for realistic reproduction of screening processes in continuous operation. Long-term effects, like, for example, the blinding of screening surfaces, the efficiency of screen cloth cleaning or the influence of different material moisture contents can be tested on industrial scale. The closed material circuit is realized by means of a C-type bucket conveyor which can circulate up to 50 m³/h. In this plant too, thanks to the modular design, screens can be simply changed over. A central PLC system is used for adjustment of the screens, dedusting and the circulated load.
For the classification and dewatering of suspensions, the closed-circuit wet screening plant is available. The wet screen was developed partly within the framework of a publicly funded research project. Especially the variety of the potential applications makes this test rig unique. Besides the possibility of conveying and classifying suspensions of water and solids with solid contents between 5 and 50 mass % at up to 40 m3/h, particle suspensions can be processed in saturated salt solutions. The classifying process is supported by a temperature adjustment device for setting temperatures between 10 °C to 80 °C. A spraying unit is fitted for reclassifying or washing the coarse material. As the influence of frequency is a key factor in screening efficiency especially in wet screening processes, the wet screens are infinitely adjustable between 16 and 25 Hz. Tests with high-frequency screens up to 50 Hz can also be conducted.
Special focus was on the compatibility of the plant with PU and steel screening surfaces as in wet screening processes these have a considerable influence on the machine size. To obtain further information or book tests, send an email to