Overview

Fully‑automatic mechanical filters serve as water‑supply treatment equipment for industrial and municipal facilities, producing treated water with outlet turbidity generally below 5 mg/L that meets potable‑water standards for industrial or domestic usage. They deliver outstanding removal performance for suspended solids in industrial wastewater. Suspended flocs and sticky colloidal particles that cannot be eliminated by sedimentation can be trapped as water passes through the filter bed inside the pressure filter, yielding clear treated water.

Also called pressure filters, mechanical filters constitute an essential pre‑treatment segment for pure‑water production and water‑purification workflows. Constructed from rubber‑lined steel or stainless steel, different filter media endow them with distinct functions. Typical types include quartz‑sand filters, activated‑carbon filters and manganese‑sand filters, usable alone or in combination.

• Multi‑media filters are filled with quartz sand, anthracite coal and other materials. They remove suspended matter, mechanical impurities and organic substances and reduce water turbidity.

• Activated‑carbon filters adopt activated‑carbon media to adsorb and eliminate water‑borne pigments, organics, residual chlorine and colloids.

• Manganese‑sand filters are packed with manganese sand, primarily removing divalent ferrous ions from raw water.

Working Principle

Mechanical filters deploy one or multiple filter media. Under a certain pressure, raw water flows through the media bed for impurity retention to realize filtration. Common packing materials include quartz sand, anthracite coal, granular porous ceramics and manganese sand, which can be selected according to on‑site requirements.

As a conventional water‑purification technology, mechanical filters rely on filter packing to lower water turbidity, intercept and remove suspended solids, organic compounds, colloidal particles, microorganisms, chlorine odour and partial heavy‑metal ions so as to purify feed water.

Mechanical filters (also named multi‑media filters or quartz‑sand filters) are pressure‑type filters filled with refined quartz‑sand filter media. When feed water flows downward through the filter bed, suspended solids and colloidal particles are trapped and water turbidity decreases. They are widely used for turbidity removal in water treatment, pre‑treatment for water softening, electrodialysis and reverse‑osmosis processes, as well as surface‑water and groundwater treatment. They effectively separate suspended solids, organics, colloids, sediment and other contaminants from water.

Application Scope

In water‑treatment workflows, they are mainly applied for feed‑water turbidity removal and pre‑treatment ahead of reverse‑osmosis and ion‑exchange softening & desalination systems; they also remove sediment from surface water and groundwater. The influent turbidity shall be less than 20 NTU, and the effluent turbidity can reach below 3 NTU.

They are extensively adopted in electronics & power generation, petrochemical industry, metallurgy & electroplating, papermaking & textile, pharmaceutical dialysis, food & beverage, domestic drinking‑water supply, plant process‑water supply and swimming‑pool water systems, satisfying liquid‑filtration demands across diverse industries.

Classification and Features

Classification

Quartz‑sand filter (sand filter), activated‑carbon filter (carbon filter), multi‑media filter, iron‑manganese removal filter (manganese‑sand filter), fibre‑ball filter, hair filter.

Features

Single‑flow mechanical filters feature simple piping and stable operation. Their filtration velocity ranges from 4 m/h to 50 m/h, with a typical service cycle of 8 hours. Double‑flow mechanical filters have water‑inlet assemblies at both upper and lower ends and a water‑outlet assembly in the middle. Their merits lie in larger treatment capacity and higher pollutant‑holding capacity with an extended operating cycle of roughly 20 hours. Drawbacks include complex piping, relatively unstable operation and difficult backwashing and media replacement.

1. Low equipment capital cost, low operating expense and easy management

2. Filter media can be reused after backwashing with long service life

3. Excellent filtration performance and compact footprint

Main Technical Parameters