Problems & Solutions

Why Does Filter Cloth Blind?

Slow Filtration & Rising Pressure Drop — 4 Causes · 3 Solutions

Filter cloth blinding is a permeability problem: fine particles or chemical scale become trapped inside the cloth pores, causing flow to fall while differential pressure rises. Diagnose pore blockage separately from cake adhesion, cloth wear or plate drainage restriction before changing the media.

The Problem

Filter Cloth Blinding

When a cleaned cloth still shows low permeability and pressure rises early in each cycle, inspect embedded fines, precipitated scale, slurry solids and aperture selection rather than treating the issue as a cake-release problem.

Common Symptoms

Significantly reduced filtration flow rate
Continuously rising pressure differential
Increased moisture content in filter cake
Difficulty discharging and releasing filter cake

Why It Happens

4 Root Causes of Filter Cloth Blinding

Fine Particle Penetration

Ultra-fine particles penetrate and lodge within the cloth pores, progressively blocking the filtration path and reducing permeability.

High Slurry Solid Content

Excessively high solid concentration causes rapid filter cake buildup on the cloth surface, sealing the pores before full filtration occurs.

Incorrect Cloth Selection

Mismatched pore size between cloth and particle distribution leads to blinding. Too coarse allows pass-through; too fine causes premature blocking.

Chemical Scale Deposits

Chemical compounds in the slurry precipitate and crystallize within cloth fibers, forming hard scale deposits that permanently reduce flow.

The Solution

3 Proven Solutions to Stop Filter Cloth Blinding

Solution 01

Optimize Cloth Selection

Select pore size matched to your particle size distribution — use higher mesh count cloth for fine particles.

Solution 02

Adjust Filtration Parameters

Reduce feed concentration moderately and increase filtration pressure to maintain optimal flow balance.

Solution 03

Regular Cleaning & Maintenance

Match the cleaning method to the deposit: remove loose solids first, then use a chemically compatible treatment only when scale analysis confirms it is required. Record clean-cloth flow after each service to identify irreversible pore blockage before production is affected.