Filter Bag Testing & Analysis

Filter Bag Testing & Analysis

Service Objectives

Is your dust collector underperforming? Are you facing unexpected filter bag failures or struggling with high energy costs? Do you know what media to choose and when to replace your filter bags? Aokai Environtec’s Filter Bag Testing & Analysis Service provides the scientific data you need to maximize the life and efficiency of your filtration system.

Key Service Objectives:

  • Key question answered: What is the root cause of premature bag failure, and how to eliminate it?
  • Value to customers: Prevents future unexpected downtime and costly emergency replacements.
  • Key question answered: What is causing the abnormally high differential pressure, and what system adjustments will restore airflow efficiency?
  • Value to customers: Lowers energy consumption and maximizes the throughput and dust filtration efficiency.
  • Key question answered: What is the filter bag’s remaining useful life, and what upgraded media to choose for the next replacement?
  • Value to customers: Enables planned maintenance, avoids reactive shutdowns, and ensures future media selections are optimal for the application.
Filter Bag Testing & Analysis

Service Descriptions

By conducting thorough filter bag testing and analysis, you can gain valuable insights into your filtration system’s condition and ensure peak performance. A systematic approach deepens your understanding of the ideal match between filter bag materials and filtration applications, empowering you to implement more effective and long-lasting solutions.

Testing Procedures:

This procedure involves:

  • Examine the failed bags for visible signs of damage like tears, holes, abrasion, or caking.
  • Assess the dust cake build-up and its characteristics (thickness, texture, adhesion).
  • Look for evidence of chemical degradation or discoloration.
  • Collect filter bag specs information, such as length, width, construction & design.

We provide comprehensive, laboratory-based analysis to determine the precise condition and cause of failure for your filter media. Our standard testing protocols adhere to international standards.

  • Physical Integrity: Measures resistance to pulling and shock forces. Quantifies fiber degradation and estimated remaining strength. Key data provided includes weight & thickness, tensile strength, and Mullen burst strength.
  • Performance Status: Measures the filter’s airflow capacity (air permeability). Indicates the severity of filter media blinding.
  • Microscopy & Chemical: Diagnoses the root cause of failure (invisible damage). Identifies corrosive and abrasive agents, and evidence of thermal damage. Technologies used include SEM (Scanning Electron Microscopy), FTIR (Fourier-Transform Infrared Spectroscopy), and EDS (Energy-Dispersive X-ray Spectroscopy).

Our laboratory is equipped with state-of-the-art apparatus. For clients requiring the highest level of predictive certainty and performance guarantee, we offer specialized testing:

  • VDI Testing: To measure baghouse filter media performance under defined conditions, such as air velocity, particle size & distribution, differential pressure (dP), and cleaning intensity & cycle. The test complies with internationally recognized standards (VDI 3926 & ASTM D6830-02).
  • Pilot Baghouse Testing:  The custom-built pilot baghouse evaluates filtration efficiency under controlled conditions, including dust loading, air velocity, and pulse-cleaning parameters.

The test data is reviewed and interpreted by a team of skilled filtration engineers. Based on the collected evidence and analysis findings, a report is compiled outlining identified failures, test data, analytical results & root causes, and recommendations for corrective actions and preventive measures.

Filter Bag Testing & Analysis

Testing Equipment

At Aokai Environtec, we are equipped with the most advanced testing equipment:

FX3300-IV Air Permeability Tester (Switzerland)

Permeability Test

Permeability Test measures the volumetric flow rate, measured in cubic feet per minute (cfm), through a square foot of filter media at a prescribed differential pressure.

The measurement is performed on the filter in the “as-received” condition and after various cleaning steps, such as lightly snapping and brushing the filtration surface to simulate a cleaning cycle. The backside (clean side) of the filter media is vacuumed as the final step. An increase in the permeability indicates dust contamination.

Filter Media Testing & Analysis

VDI 3926 Test

VDI 3926 Test is to simulate the real-world, cyclical operation of a filter to determine its long-term performance. The test involves:

  1. Cyclic Operation: Running the filter media through repeated cycles of dust loading and cleaning under controlled conditions.
  2. Long-Term Performance: Evaluating critical parameters over many cycles, which include:
    • The residual pressure drop after cleaning (a measure of cleanability).
    • The filtration efficiency and particulate emissions.
    • The cycle time until cleaning is required.
pilot baghouse 1

Pilot Baghouse Test

A Pilot Baghouse Test offers customers a powerful way to test their filter bags or validate new media against representative process conditions. By utilizing a small-scale baghouse, the service allows us to test filter bags along with either a sample of actual dust or a standardized simulant dust to rigorously assess bag performance. This testing yields vital data on filtration efficiency, pressure drop, and bag life, enabling the customer to choose the best filter media and optimize their full-scale baghouse operations.

filter media tensile strength testing device

Tensile Strength Test

Tensile Strength Test is a measure of the directional strength of the media, measured in pounds per square inch. The sample is secured in the testing machine and is pulled apart to the point of failure. A resultant load-displacement curve is developed which is then compared to new material for residual property characteristics.

sem thermofisher

Microscopic Analysis

Visual analysis of a filter sample is aided by the use of a light microscope. In addition to observing the failure site, determining the particulate interaction with the filter media surface is often critical in solving filter media performance issues. Scanning Electron Microscopy (SEM) is also very helpful when investigating particulate and filter fiber surface morphology. Evidence of abrasion, chemical, and thermal effects is often enhanced during Microscopic Analysis.