The automatic backwash filter is composed of one or more filter circuits connected to the main pipeline by the inlet valve and the outlet valve. Each filter circuit is called a "column", and each column of filters consists of several filter units. The number of filter units in each column of filters and the total number of columns of backwash filters are determined according to the required process characteristics, namely flow, flow rate, viscosity, average particle content in the medium, and some other process parameters.When working normally, the raw material medium enters the lower part of the filter shell through the inlet valve of the filter, then passes through the filter element from outside to inside, enters the upper part of the filter, and enters the subsequent process through the outlet, and the impurities in the liquid are intercepted by the filter element in the filter element. On the outer surface, when the impurities on the surface of the filter element accumulate more and more, and gradually form a filter cake, the effective filtration area of the filter element decreases, and the pressure difference between the inlet and outlet gradually increases. When the pressure difference reaches the set value, the control program follows the programmed Output signal to control the action of the actuators of each valve for backwashing. During the backwashing period, only one group of filter units is in the backwashing state, while the other groups of filter units are always in the online working state, which can filter the raw material medium uninterruptedly. Backwashing form There are two types, namely internal backwash and external backwash.
