ZL Type Self-Cleaning Reverse Osmosis Filter

I. Features and Applications

The ZL type backwashing self-cleaning filter is widely used in metallurgy, chemical industry, petroleum, papermaking, food, mining, power, and urban water supply fields. It is suitable for filtering industrial wastewater, recycling water, regenerating emulsified liquids, filtering and treating waste oil, and in metallurgical industry continuous casting water systems, blast furnace water systems, and high-pressure water descaling systems for hot rolling. It is an advanced, efficient, and easy-to-operate fully automatic filtration unit.

Section 2: Equipment Structure and Working Principle

The ZL type self-cleaning filter with backwashing feature consists of the shell, multi-core filter, backwashing mechanism, electrical control box, reducer, electric valve, and differential pressure controller. The transverse partition inside the shell divides the internal cavity into upper and lower chambers. The upper chamber is equipped with multiple filter cores, maximizing the use of filtering space and significantly reducing the filter's volume. The lower chamber is fitted with a backwashing suction cup. During operation, the turbid liquid enters the lower chamber of the filter through the inlet, then passes through the partition holes into the inner chamber of the filter cores. Impurities larger than the gaps of the filter cores are retained, while the clean liquid passes through the gaps to the upper chamber and is then discharged through the outlet.

This filter's core utilizes a high-intensity Johnson wedge-shaped filter screen, which automatically cleans the core through differential pressure control and timing control. When impurities accumulate on the core surface within the filter, causing the differential pressure between the inlet and outlet to increase to a set value, or when the timer reaches the preset time, the electric control box sends a signal to activate the backflushing mechanism. When the backflushing suction port is aligned with the core inlet, the drain valve opens, releasing system pressure and draining. A negative pressure zone with a relative pressure lower than the core exterior water pressure forms inside the core, forcing some clean recirculating water to flow from the exterior to the interior of the core. The impurities adhering to the core inner wall are washed into the suction port with the water flow and expelled through the drain valve. The specially designed Johnson screen creates a jet effect inside the core, ensuring any impurities are flushed away from the smooth inner wall. Once the differential pressure between the filter's inlet and outlet returns to normal or the timer's set time has elapsed, the motor stops, and the electric drain valve closes. Throughout the process, material flow is continuous, with minimal backflush water usage, achieving continuous and automated production.

Section 3: Machine Features

This filter's deceleration mechanism uses an NRV type decelerator, with an aluminum alloy die-cast housing that offers good heat dissipation, low noise, light weight, and high load-bearing capacity.

● The sealing device employs the CVA62.1-85 standard to enhance the four-fluorine double-face sealing structure, ensuring reliable sealing performance, long service life, and strong pressure-bearing capacity.

● Equipped with an automatic exhaust valve at the top, the structure is compact and the operation is sensitive.

The pressure difference sampling section utilizes a D520/7DD type switchable differential pressure controller, with correct signal feedback.

● The filter cores utilize high-strength Johnson filter mesh, offering high gap rate, large effective filtering area, low pressure drop, and high backwashing efficiency.

● The filter core plate is made of 304 stainless steel and is mirror-polished at the interface with the backwash suction cup.

● The reverse flush suction cup features an enhanced polytetrafluoroethylene structure and an automatic alignment mechanism for the reverse flush suction cup, ensuring long-lasting sealing between the suction cup and the filter core plate, enhancing the reverse flush effect.

● This filter's electrical control section uses an SRBC programmable controller, featuring differential pressure control, timing control, and manual control in parallel. The cleaning program utilizes a timing positioning mode, with low backwash water consumption and thorough cleaning.

The control box features a pillar-type full-transparent screen outdoor waterproof structure.

IV. Main Technical Parameters

Nominal Diameter: 150, 200, 250, 300, 350, 400, 500, 600, 700, 800, 900, 1000, 1200

Design Pressure: 1.0 MPa (Additional options available in 1.6 MPa and 2.5 MPa)

● Filtration Precision: (1) Perforated Plate Structure: ≥1000μm (2) Composite Woven Mesh Structure: ≥25μm (3) Johnson Wedge Mesh: ≥50μm

● Differential Pressure Setting Range: 0.02～0.16 MPa

● Switching differential adjustment range: 0.035～0.15 MPa

● Backwash time setting range: 1-24h

Pressure Drop: 0.02～0.1 MPa

● Operation Method: Manual, Automatic

Motor Parameters: 380V 50Hz

● Motor Power: 0.15～2.2 kW

Section 5: Product Dimensions