The rotary drum screen, or rotary sifter, is part of the equipment usually found in municipal and industrial water treatment processes. This is the second pre-treatment process used in wastewater treatment plants after screening. It is generally placed upstream of the system, i.e. at the discharge of the pumping station which is in charge of collecting the wastewater. In addition, the sifter can collect mechanically fine and coarse debris such as trash rack debris (RAG), thick sands or grease… This way, the waste will not be mixed with mud and will not interfere with the downstream process.