The filtration mechanism of the automatic backwashing disc filter lies in the combination of surface filtration, deep filtration and compacted plastic laminates. The core technology is the laminated body, which is composed of polypropylene laminated bodies with grooves in different directions on both sides. After two adjacent stacked bodies overlap, multiple intersection points are formed at the edges of the grooves on the adjacent sides. These intersections form multiple cavities and irregular channels. When these channels are filtered from the outside in, they cause turbulence in the water. Ultimately, impurities in the water are blocked at every intersection. When the laminates are stacked on the frame of the filter element, under the pressure of the spring and water, The outer side will loosen, forming a filter unit with the inner side tightened. Next, let's take a look at the working principle and detailed structural analysis of the automatic backwashing disc filter!

The depth and quantity of the stacked grooves determine the filtration accuracy of the filter unit.

Work status

During the filtration process, the automatic backwashing disc filter is tightly squeezed by the spring force and hydraulic pressure. When water containing impurities passes through, large particles and coarse fibers are directly blocked - this is what is called surface filtration.." Small particles and fibers enter the holes of the grooves and enter the interior of the laminated material. Then, as the gap becomes smaller, Fine particles and fibers are cut in the middle of their respective channels. This is called deep filtering.

Automatic backwashing disc filter

The multi-column automatic backwashing disc filter adopts high-strength wedge-shaped metal wire mesh filter elements. Automatic cleaning is achieved through differential pressure control and timing control. When impurities accumulate on the inner surface of the filter element, the pressure difference between the inlet and outlet increases to the set value, or when the timer reaches the preset time, the electrical control box sends a signal to drive the backwashing mechanism.

When the inlet of the backwash suction cup is aligned with the inlet of the filter element, The drain valve is open. At this point, the system depresses and drains water, creating a negative pressure zone inside the suction cup and filter element where the relative pressure is lower than the external water pressure of the filter element (the backwash pressure difference is controlled at 3 to 4 times the filtration pressure difference).

A portion of the clean circulating water is forced to flow from the outside to the inside of the filter element. The impurity particles adsorbed on the inner wall of the filter element enter the tray with the water flow and are discharged through the drain valve.