The modular backwash filter adopts PLC full intelligent control, which can filter online for a long time, and can perform backwash regeneration of the filter element without stopping the machine.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 filter column 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.

Internal backwashing is to use the filtered raw material as the backwashing medium. When the control system receives the backwashing signal, the raw material liquid inlet valve of a filter unit of the filter is closed, and the sewage valve is opened. Under the action of its own pressure, the filtrate is reversed. Flush the solid particles accumulated on the outer surface of the filter element and discharge them into the oil pipe, then close the drain valve, open the raw material inlet valve, put this set of filter units into filtration, and backwash the next set of filter units until all The filter units are backwashed one by one, and the backwashing is over, and the filter enters a normal operating state, waiting for the next backwashing signal to arrive. Internal backwashing is suitable for occasions where the raw material medium has less colloid content, good fluidity, and outlet pressure greater than 0.4MPa.