Last week I worked with an OEM who was looking for a more effective method of cleaning the wire mesh on the rotary screeners they manufacturer. Rotary screens, also know as trammel screens (think of a washing machine drum), separate solid materials by passing the parts through a rotating perforated cylinder, typically elevated on the feed side, to help keep the material moving through to the exit side. With the spiraling motion of the cylinder, the smaller parts begin to pass through the mesh screen, where they are commonly recovered in some type of hopper or fed onto a conveyor system.
In this particular application, their proprietary machine design features a non-vibratory system used in separating pet foods. The screener is working as far as separation but the problem they were having was as the pet food passes through the rotating mesh cylinder, it leaves an oily residue on the screen. Due to this being a food application, they are unable to use any type of cleaning brush over concerns that some of the fibers may break loose, contaminating the finished product, so they were looking at using air as an alternative solution.
I recommended they incorporate our 48″ Stainless Steel Super Air Knife in the application. The Super Air Knife is our most efficient unit, as far as compressed air usage, using only 2.9 SCFM per inch of knife when operated at 80 PSIG supply. The end to end, high velocity airflow produced by the unit would span the 48″ width of the screen. The top of their machine is removable, so I suggested they also incorporate our Model # 9060 Universal Mounting System. The Model # 9060 provides for an easy installation as well as a simple way to change the distance and direction of the knife to provide the most effective blowoff. With the cover off, they could easily move the knife into position to perform the cleaning.
If you are considering an Air Knife to use in your process and would like to discuss the application, please give us a call at 800-903-9247.
Trommel and sluicebox image courtesy of Roy Luck via Creative Common License