Wedge Wire Pressure Arc Screen for Starch

Pressure arc screen is one of popular types of curved screen. It is commonly used in 120° for high filtering and separating efficiency.

The screen consists of surface wedge wires, support rods and frame.

Surface wedge wire. Surface wedge wire is commonly in triangle shape and is resistance welded onto the support rib. The surface wire is designed to allow the starch slurry to flow through the screen surface while retaining any solid particles and impurities that are larger than the slot size of the screen. The surface wire is also designed to be easily cleaned and maintained, ensuring that the screen operates at maximum efficiency and produces a high-quality and contaminant-free starch product.

Support rod. Support rod is positioned behind the screen surface and is used to reinforce the screen and prevent it from deforming or bending under the pressure of the starch slurry. In addition to providing structural support, the support rod also helps to distribute the pressure of the starch slurry evenly across the screen surface, ensuring that the screen operates at maximum efficiency and reducing the risk of blockages or clogging.

Frame. The frame supports and secures the screen during operation. It is typically made of high-quality stainless steel and is designed to withstand the high pressure and flow rates of the starch slurry. It can ensure the proper alignment and positioning of the screen during operation. This helps to optimize the screening efficiency and ensure the reliable operation of the screen, leading to a high-quality and contaminant-free starch product.

The screen is positioned in a cylindrical housing and is subjected to high pressure, typically between 2 and 4 bar, depending on the specific application.

The liquid to be screened, such as starch slurry, is fed into the housing from the nozzle under a pressure of 0.2–0.4 MPa at the center of the screen. As the liquid flows through the narrow slots, the solid particles and impurities are trapped on the surface of the screen, while the clean liquid (starch and water) passes through and is collected at the pulp outlet.

The trapped particles and impurities are periodically removed from the surface of the screen by a backwash or flushing system. The backwash system typically uses water or air to flush the particles from the screen, which are then collected for further processing or disposal.

The pressure arc screen is designed to operate under high pressure, which helps to remove fine particles and impurities from the liquid. The curved shape of the screen surface also ensures that the liquid flows uniformly across the screen, further enhancing its screening efficiency.