Working principle
A- S 660 series sand filter which use quartz sand as a filter medium is a high efficiency filter, It can effectively remove the suspended substance, microorganisms, and other fine particles in water. Ultimately achieve to reduce water turbidity, purify water quality. When the filter work normally, sewage through the water inlet to the dielectric layer, then a majority of the contaminants trapped in the medium surface, fine dirt and other floating organic matter trapped in the medium layer. When the
impurity in the water and suspended matter reaches a certain amount of time, the filter system through the differential pressure control device for real time detect the pressure difference between inlet and outlet. When the pressure reaches the certain value, the electric control PLC send signals to the three way solenoid valve of control system. The three way electromagnetic valve through a water automatic control corresponding to the filtering unit three way valve, closing the inlet channel and at the same time to open the discharge channel, because the discharge channel less pressure, other

filtration unit of water in water under pressure from the outlet of the filter unit to enter, and continued to scour the filtration unit of the dielectric layer, thereby achieve cleaning the medium effect, after rinsing wastewater under the action of water pressure by the filtering unit of the sewage outfall into the sewage pipe, then complete a sewage process. This kind of filter can also be used for timing control of sewage, when time reaches the set time timing controller, electric control box issued a clean signal to the three electromagnetic valve, the discharge process as above.

Feature description
(1).Sand filter with high precision, can increase the multi-layer filter medium, large filtering area. Low pressure loss, can realize the large flow, high precision filter, the traditional filter is difficult to achieve.
(2).Various pollutant discharge control modes: automatic control,pressure control, manual control.
(3).Sand filter repair, maintenance conveniently, set inspection station, replacing the filter medium is convenient.
(4).Using the sequential filtering, when cleaning the dirt, one by one, when cleaning the uninterrupted water supply, constant flow.
(5).Advanced control system: control system according to different water to adjust its working mode and operating condition, can adapt to various water quality ability.
(6).Can achieve local control and remote control: if the site circumstances is special, the operator inconvenience into, can be additionally provided with remote control function.
(7). Medium filter control system possesses running status output, fault alarm output function, to ensure the equipment safe and reliable.
(8).Filter unit uses ultra low carbon austenitic stainless steel.Has strong corrosion resistance, high temperature resistance, creep resistance, etc.
(9).Sand filter is usually made of high quality steel cylinder body, special structure of the water collecting device, the advanced control system and pollution discharge device.
(10).Connection way is flange. General is GB flanges, strong versatility.