This article explains what air filters are, what they are used for, their main types, and applications with cases.
1. What is an Air Filter?
An air filter is a device that purifies air through physical or chemical methods, designed for factories, workshops, laboratories, etc. Its core functions include:
Trapping particles: Dust, metal debris, smoke (e.g., PM2.5/PM10).
Adsorbing harmful gases: VOCs, acidic gases.
Controlling microbial contamination: Bacteria, viruses.
Components & Principles:
Filter media: Glass fiber, metal sintered mesh, PTFE membrane.
Structure: Filter cartridges, filter bags, panel frames (adapt to different airflow needs).
Working principles: Capture pollutants via gravity settling, inertial impaction, electrostatic adsorption.
2. Main Types of Air Filters
High-Temperature Resistant HEPA Air Filter With Separator
Standard Sub-HEPA Air Filter With Separator
HEPA Air Filter With Separator (High Airflow)
V-Bank Standard HEPA Air Filter
Standard HEPA Air Filter With Separator
HEPA Air Filter Separator-Free (High Airflow)
Standard ULPA Air Filter Separator-Free
3. Core Functions of Air Filters
(1) Preventing Explosions & Safety Hazards
Trapping combustible dust (e.g., aluminum/coal powder) below explosive limits.
Case: ThyssenKrupp Steel Plant (Germany) used ATEX-certified filter cartridges to reduce blast furnace flue dust from 200g/m³ to 5g/m³, avoiding electrostatic ignition.
(2) Protecting Equipment & Product Quality
Preventing particle-induced mechanical wear or product contamination (e.g., chips, pharmaceuticals).
Case: TSMC’s 5nm chip cleanroom used ULPA U17 filters to intercept 99.9999% of ≥0.1μm particles, ensuring wafer yield ≥95%.
(3) Ensuring Hygiene & Biosafety
Blocking microbial contamination (e.g., bacteria in vaccine production).
Case: Pfizer installed H14 HEPA filters on filling lines, achieving ISO 14644 Class 5 cleanliness (≤3,520 particles/m³).
4. Applications & Case Studies
(1) Chemical & Petrochemical
Scenario: Trapping catalyst dust, adsorbing H₂S gas.
Case: Saudi Aramco Refinery used ceramic fiber + activated carbon filters, reducing acidic gas emissions by 90%.
(2) Pharmaceuticals & Biotech
Scenario: Maintaining sterile environments, filtering viruses/bacteria.
Case: Johnson & Johnson’s vaccine facility used isolators + U15 ULPA filters, ensuring ≤0.1 CFU/m³ airborne bacteria in filling zones.
(3) Automotive Manufacturing
Scenario: Purifying paint mist in coating workshops, protecting robots.
Case: Volkswagen Germany deployed electrostatic paint recovery systems, reducing overspray waste by 180 tons/year.
(4) Energy & Metallurgy
Scenario: Filtering high-temperature fumes, recovering precious metal dust.
Case: POSCO (Korea) installed metal sintered plate filters on sintering machines, recovering 12,000 tons/year of zinc dust (worth USD 26 million).
(5) Food Processing
Scenario: Intercepting allergenic particles (e.g., milk powder, starch).
Case: Nestlé Switzerland used food-grade stainless steel filters, complying with EU EC 1935/2004.
5. Summary: Key Roles of Air Filters
Air filters are barriers for safety and drivers for efficiency, with core functions:
Explosion prevention: Controlling combustible dust/gas concentrations.
Equipment protection: Extending machinery lifespan, reducing downtime.
Regulatory compliance: Meeting global environmental laws.
Hygiene assurance: Blocking contamination chains.
Selection advice: Match filter types to industry needs (particle type, temperature, regulations) and monitor pressure drop/efficiency for optimal ROI.
