In 2008 planning commenced for the new lime processing and calcining plant at the Saal site operated by the company Fels-Werke. The plant is designed for a running time and operating lifetime of 40 years, the annual production rate is to range between around 110 000 and 140 000 t. Maerz, a leading manufacturer of lime shaft kilns also involved in this project, has been successfully using roller screens supplied by Sandvik for many years now. Together the two companies therefore decided to integrate a Sandvik roller screen in the processing of the lime ready for calcining; the roller screen is installed directly in front of the filling opening of the kiln.
Key features of the SR roller screen (Fig. 1), which was specially developed to handle wet materials such as limestone, marl, clay, gypsum rock as well as chalk, slate, coal and lignite, is its compact design, easy handling and excellent engineering, which guarantee constant screening performance even in the severe conditions of the winter months. Conventional screens blind over time, leading to downtime in the cleaning process or unwanted different screened grain sizes. The Sandvik SR roller screen, on the other hand, ensures non-clogging operation and is designed for pre- and intermediate screening of large volumes of low-abrasive materials. It is available in 12 standard models with sizes ranging from 1200 x 2000 mm to 2400 x 6000 mm.
Since commissioning of the plant in September 2009, the Sandvik SR roller screen has operated very efficiently (Fig. 2). The maximum throughput of the plant is 100 t/h. Limestone in sizes up to 60 mm is fed over the entire width of the roller screen. It is cut at 15 mm, that is fine and flaky material < 15 mm is screened off. The cleaned material stream of limestone in the size 15/60 mm is then fed to the kiln.
Sandvik Mining and Construction Central Europe GmbH, Lutz Kaufmann, Equipment Sales Manager Crushers and Screens, Tel. +49 174 3367-313, E-Mail: email@example.com, www.sandvik.com