Multi-column Automatic Backwash Filter

Overview

Multi-column Automatic Backwash Filter is an advanced, high-efficiency and easy-operated fully automatic filtration equipment. This Multi-column Automatic Backwash Filter is widely applied in metallurgy, chemical industry, petroleum, paper making, pharmaceutical, food, mining, electric power, municipal water supply and other sectors. It handles industrial condensate, washing water, wastewater and circulating water, and serves for continuous casting water systems, high-pressure water descaling systems in hot rolling mills and other metallurgical water circuits.

The equipment consists of pressure vessel housing, filter elements, backwash rotating mechanism, differential pressure controller and electrical control cabinet. The filter cartridge is made of high-strength Johnson wedge wire screen or woven metal mesh. It triggers cleaning by two modes: differential pressure alarm or preset timer. When contaminants accumulate on the inner surface of filter elements and the pressure difference rises to the set value, or the preset cycle time arrives, the control unit activates the backwash mechanism. As the suction scanner aligns with a filter element, the drain valve opens, forming a negative pressure zone inside the scanner. Part of the filtered clean water flows backward through the filter media, stripping off particulate sludge attached to the inner wall of the screen. The contaminants are carried into the suction tray and discharged through the sewage outlet. The backwash differential pressure is controlled at 3–4 times the normal filtering differential pressure for thorough cleaning.

Product Features

• Microcomputer program control: automatic filtration, differential pressure detection, automatic backwashing and automatic sewage discharge, low operation cost.

• Uninterrupted operation: cleans filter elements one by one, without stopping the whole filtration process.

• High efficiency and low energy consumption: large effective filtration area, low backwash frequency, small sewage discharge volume and low pressure loss.

• Excellent cleaning performance: special screen structure and suction control deliver strong backwash force for complete dirt removal.

• Wide filtration range: available precision from 10 μm to 3000 μm, adaptable to diverse raw water conditions.

Application Fields

This Johnson wedge wire screen filter is suitable for many heavy-duty industrial water treatment scenarios.

• Metallurgy: Filtration for heavy metal recovery washing water, cooling circulating water and condensate, to protect nozzles and water pumps and stabilize long-term operation.

• Chemical & Petrochemical: Purification of brine, process water and circulating cooling water to remove suspended solids and improve medium quality.

• Power Plant & Thermal Power Plant: Treatment for electrostatic precipitator spray water, ash water and condensate in desulfurization systems, stabilizing water quality and protecting downstream equipment.

• Oilfield: Removing suspended solids in oilfield produced water to meet reinjection water standards.

Technical Parameters

Filter Media: Johnson wedge wire screen / woven metal mesh 

Filtration Precision: 10 ~ 3000 μm 

Control Mode: Differential pressure control / timing control 

Working Mode: Online continuous filtration, sequential backwashing

Backwash Structure: Rotating suction scanner 

Housing Material: Carbon steel / stainless steel (optional)

FAQ

Q1: What are the trigger modes for this Multi-column Automatic Backwash Filter? 

A1: It supports both differential pressure triggering and fixed-time triggering; users can set and switch according to working conditions.

Q2: What is the advantage of this Johnson wedge wire screen filter compared with ordinary self-cleaning filters? 

A2: The wedge wire screen has high mechanical strength, is not easy to deform, and the suction-scan backwash method realizes element-by-element cleaning without system shutdown.

Q3: Can it keep filtering while backwashing? 

A3: Yes. Only one column is cleaned at a time; the rest of the filter columns keep working, achieving uninterrupted filtration.

Q4: What kind of impurities is it good at removing? 

A4: It mainly intercepts suspended particles, sediment, rust and fine solid contaminants in various industrial water systems.

Q5: Can we customize the material, size and precision for the Multi-column Automatic Backwash Filter? 

A5: Yes. We can customize housing material, filter precision, connection size and control cabinet configuration according to site requirements.