New screening techniques for the new millennium - The MuST screen

This paper describes Valmet's newest innovation in screening technology. The paper discusses benefits of multistage screening (MuST Screen) in mechanical pulp and papermachine broke. The multistage screen makes it possible to replace several separate screens with only one screen. The multistage screen has many advantages compared with single screens, such as cost effectiveness, reduced energy consumption, excellent runnability, easy and quick reaction to controls, simplified process and excellent pulp quality. The relevant information for this paper came from a Finnish groundwood mill using the multistage screen in production since 1996, where production in one single screen is 400 t/d in 4 stages. In addition, some results from broke screening with the multistage screen are discussed.