Rotary drum fine screen is a core solid-liquid separation equipment used for sewage treatment, which achieves impurity interception and automatic cleaning through mechanical rotation and filtration technology. The core workflow is as follows:
1.Basic workflow of the drum fine screen
Sewage entry and preliminary filtration
Wastewater enters the interior of the drum screen through the inlet (internal inlet type) or overflows to the surface of the drum (external inlet type), with the water flow direction inclined at a 35 ° angle to the drum axis, enhancing the efficiency of impurity retention.
The surface of the drum is covered with a stainless steel filter (pore size 20-50 μ m), and solid impurities (such as fibers, plastics, suspended solids) are intercepted on the inside or surface of the filter. The filtered water is discharged through the pores.
Drum rotation and impurity lifting
The driving device drives the drum to rotate at a low speed of 2-5 r/min, and the trapped impurities gradually rise to the upper part of the drum as the filter rotates.
Built in rake teeth or cleaning arms rotate synchronously, penetrating deep into the grid seam to assist in peeling off attached impurities and prevent blockage.
High pressure flushing and impurity collection
The high-pressure spray system (pressure 0.3-0.5MPa) located at the top of the drum backwashs the filter screen in reverse, flushing impurities into the spiral conveyor bucket.
The rotating drum screen is designed with variable pitch for extrusion dewatering, reducing the moisture content of the slag to below 65%, and finally discharging it into the collection container.
Purified water discharge and circulation control
The filtered water flows out from the outside of the drum, with a suspended solids removal rate of ≥ 95%, meeting the requirements of subsequent treatment processes.
The intelligent control system automatically starts and stops based on water level differences or time intervals, supporting continuous or intermittent operation modes.