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Chemical Filtration Systems | PSA, DBS, CA & WGP | YONGFAN
ANSI/ISA-71.04 Class G1 · ISO 10121-1/2 Testing · Up to 100,000+ m³/h

Chemical Filtration Systems: Gas-Phase Corrosion & Emission Control

Chemical filtration systems remove molecular contaminants that particulate filters cannot capture; selecting the wrong unit can leave electronics exposed or send untreated gases to exhaust.

Compare YONGFAN PSA Fresh-Air Filtration (850–34,000 m³/h), PSA-PG High-Airflow Filtration (1,700–68,000 m³/h per unit), DBS & CA Recirculation Scrubbers (850–6,800 m³/h), and WGP Exhaust Gas Treatment Units (up to 100,000+ m³/h with ≥99% H2S/SO2 removal).

PSA Fresh Air850–34,000 m³/h · Class G1
PSA-PG High Flow1,700–68,000 m³/h · 2x Flow
DBS / CA RecircIn-Room Polishing · MediaPAK
WGP ExhaustUp to 100,000+ m³/h · ≥99% H2S
Select a Chemical Filtration System Chemical Systems Matrix
YONGFAN PSA fresh-air chemical filtration unit
Molecular Contaminant Removal Adsorption · Chemisorption · ANSI/ISA-71.04 Class G1 · ISO 10121 Compliance
01 / Gas-Phase Physics

Gas-Phase Failures Begin When Particles and Molecules Are Treated as the Same Contaminant

A particulate filter can look spotless and still allow corrosive gases (H2S, SO2, Cl2, NH3, VOCs) to pass directly into electronics rooms, causing micro-corrosion failures.

Gaseous molecules pass unobstructed through HEPA fibers because filtration mechanisms must change from physical particle interception to adsorption, chemisorption, or multi-stage chemical reaction.

Airflow roles must be kept distinct: PSA / PSA-PG treats outdoor fresh-air intake; DBS / CA polishes recirculated indoor room air; and WGP cleans outgoing toxic, corrosive, or odorous exhaust streams before stack release.

Chemical beds do not show exhaustion through pressure drop changes alone. Service life planning depends on gas concentration, residence time, and coupon reactivity monitoring.

YONGFAN deep-bed chemical filtration unit

ISO 10121-1 and ISO 10121-2 establish laboratory test methods for gas-phase air-cleaning media and devices. Environmental corrosion severity for electronics rooms is benchmarked against ANSI/ISA-71.04 Class G1 (mild, <300 Å/30 days copper reactivity).

Adsorption & Chemisorption

Virgin activated carbon physically adsorbs VOCs; impregnated chemical media irreversibly neutralizes acid gases (H2S, SO2, Cl2).

Chemical Reaction Media

ANSI/ISA-71.04 Class G1

Maintains control room environment severity below 300 Å copper corrosion to ensure DCS, PLC, and server warranty compliance.

Electronics Protection

Duty-Specific Separation

Fresh-air pressurization (PSA/PSA-PG), indoor room recirculation (DBS/CA), and process stack exhaust (WGP) have dedicated designs.

Intake vs Exhaust Routing
02 / Product Architecture

Match the Family to Where the Contaminated Air Is Moving

Detailed technical features across PSA fresh-air units, PSA-PG high-capacity scrubbers, DBS/CA recirculation scrubbers, and WGP exhaust treatment units.
Family 01 · Standard Control-Room Fresh-Air Intake 850–34,000 m³/h · ANSI/ISA-71.04 Class G1

PSA Chemical Filtration Unit for Fresh-Air Intake

Cleans incoming outdoor ventilation air for central control rooms, DCS rack rooms, and substation switchgear spaces in petrochemical, refining, and chemical plants.

Airflow Range850 to 34,000 m³/h (approx. 500 to 20,000 CFM)
Target SeverityANSI/ISA-71.04 Class G1 target (<300 Å/month Cu)
Gases RemovedH2S, SO2, Cl2, NOx, NH3, VOCs, mercaptans
ApplicationControl room blast-wall intake, electrical substation fresh air
View PSA Fresh-Air Units Request PSA Sizing
YONGFAN PSA fresh-air chemical filtration unit
PSA Series 850–34,000 m³/h · Control Room Fresh Air · Class G1 Environment
Family 02 · High-Capacity Control-Room Intake 1,700–68,000 m³/h · Double PCB Chemical Beds

PSA-PG High-Airflow Chemical Filtration Unit

Delivers twice the airflow capacity per unit footprint of standard PSA units, utilizing a robust G4 pre-filter + 2 PCB chemical media stages + F8 final filter train with 2,000 Pa casing pressure rating and toxic gas interlocks.

High Airflow1,700 to 68,000 m³/h per unit (2x standard PSA capacity)
Filtration TrainG4 pre-filter + 2 chemical stages + F8 final filter
Casing Pressure2,000 Pa structural rating · leakage <1% @ 1,000 Pa
Safety InterlocksAutomatic intake shutoff on toxic or combustible gas detection
View PSA-PG High-Flow Units Request PSA-PG Sizing
YONGFAN deep-bed chemical filtration unit
PSA-PG Series 1,700–68,000 m³/h · 2x Footprint Airflow · Casing Leakage <1% @ 1 kPa
Family 03 · Indoor Recirculation & In-Room Polishing CA 850–6,800 m³/h · MediaPAK · DBS ~2yr Interval

DBS & CA Recirculation Chemical Filtration Scrubbers

Dedicated in-room air scrubbers designed for server rooms, data centers, archive vaults, and control rooms where indoor gas contaminants and personnel ingress require continuous internal polishing.

CA Purifiers850 to 6,800 m³/h with plug-in MediaPAK cartridges
DBS UnitsHigh-durability indoor/corridor scrubbers with ~2-year media life
Quiet OperationLow radiated noise design for occupied data and equipment rooms
Stand-Alone FitOperates independently without modifying existing AHU chillers
View Recirculation Scrubbers Request Recirc Sizing
YONGFAN PK12 chemical filtration module
DBS & CA Series Indoor Air Polishing · MediaPAK Quick-Change · Data Center Electronics
Family 04 · Industrial Process & Odor Emission Control Up to 100,000+ m³/h · ≥99% H2S/SO2 Removal

WGP Exhaust Gas Treatment Units

High-capacity industrial exhaust scrubbing units designed to remove toxic, corrosive, and odorous chemical gases before stack discharge. Features deep-bed virgin activated carbon combined with chemical reaction stages.

High CapacityCustom engineered from several thousand to 100,000+ m³/h
Carbon SpecIodine ≥1,000 mg/g · hardness ≥95% · CTC adsorption ≥60%
Removal Rates≥99% for H2S and SO2 · ≥95% for TVOC
OGP PairingPairs seamlessly with OGP tank covers for wastewater odor control
View WGP Exhaust Systems Request WGP Sizing
YONGFAN deep-bed fresh-air chemical filtration system
WGP Series Up to 100,000+ m³/h · Deep-Bed Carbon + Chemisorption · Emission Compliance
03 / Selection Matrix

Chemical Filtration Family Comparison Table

Side-by-side comparison across fresh-air, high-airflow, recirculation, and exhaust-gas treatment lines.
Product Family What It Solves Documented Airflow Boundary First Input to Confirm Action
Fresh-Air Chemical Filtration (PSA)
 Corrosion-controlled outdoor air for control rooms and protected electronics
PSA: 850–34,000 m³/h
 Fresh-air quantity and outdoor gas analysis Configure PSA
High-Airflow Chemical Filtration (PSA-PG)
 Higher-volume control-room intake with fewer units
PSA-PG: 1,700–68,000 m³/h per unit
 Required fresh-air volume and room pressurization Configure PSA-PG
Recirculation Chemical Filtration (DBS/CA)
 Indoor/cabinet gas-phase corrosion control
CA: 850–6,800 m³/h; DBS sized by room duty
 Room volume, infiltration and target environment Configure Recirc
Exhaust Gas Treatment (WGP)
 Treatment of toxic, corrosive or odorous exhaust before discharge
WGP: Several thousand to 100,000+ m³/h
 Exhaust airflow and full gas composition Configure WGP
04 / Engineering Procurement

Chemical-Filtration Enquiries Should Start with a Gas Analysis

Essential parameters to confirm before sizing gas-phase chemical filtration media beds.
Gas Sizing Protocol

Key Chemical Parameters

Submitting your target gas species, peak/average concentrations (ppm/ppb), airflow, room volume, temperature, and humidity allows our chemical engineers to calculate media mass and bed residence times.

1. Gas Species (H2S, SO2, Cl2, NOx, NH3, VOCs)
2. Average & Peak Gas Concentrations (ppb, ppm, mg/m³)
3. Design Airflow Rate (m³/h or CFM)
4. Protection Role: Fresh Air (PSA) vs Exhaust (WGP)
5. Environmental Target: ANSI/ISA-71.04 Class G1
6. Operating Air Temperature (°C) & Relative Humidity (%RH)
7. Monitoring: Copper/Silver Coupons or Online Monitor
8. Control Interlocks & Gas Leak Detection Relays
05 / Testing & Standards

Third-Party Testing and Chemical Media QA

Tested against GB/T 14294-2008 and GB/T 34012 with UL/SGS certified media fire safety and SDS documentation.
Efficiency Testing

GB/T 34012 Efficiency

Gas purification efficiency tested in accordance with GB/T 34012; whole unit performance evaluated to GB/T 14294-2008.

Carbon Quality

Activated Carbon QA

Virgin coal/coconut activated carbon checked for iodine number (≥1,000 mg/g), ball-pan hardness (≥95%), and CTC adsorption (≥60%).

Fire Safety

UL / SGS Certification

Chemical media tested to UL 900 / UL/SGS fire safety standards with accompanying Safety Data Sheets (SDS).

Custom Fabrication & Lead Time: WGP and PSA-PG systems are fabricated to project drawings. Large modules can be segmented for containerized transport. EXW, FOB, CIF, and DDP terms supported.
06 / Architectural Boundaries

Chemical Filtration Is Not a Substitute for Source Control or Ventilation

Understanding the operating boundaries of gas-phase filtration.

Room Pressurization

Control rooms require positive pressure (+25 to +50 Pa) to prevent fugitive outdoor gas ingress through door gaps and cable penetrations.

Pressure Maintenance

Particulate Pre-Filtration

Always maintain G4/F8 particulate pre-filters to prevent atmospheric dust blinding chemical pores and reducing gas adsorption capacity.

Dust Protection

Media Replacement Tracking

Monitor media life via periodic laboratory residual-capacity testing or copper reactivity coupons rather than relying on pressure gauges alone.

Chemical Bed Lifecycle
ALERTS — NOT PART OF THE PAGE. RESOLVE BEFORE PUBLISHING.
Ensure that documented removal percentages (≥99% H2S/SO2) are quoted with specific bed contact times, face velocities, and challenge gas concentrations.
Verify UL 900 media test certificates and SDS toxicological safety sheets for the specific chemical media blend ordered prior to final project handoff.
07 / Technical Q&A

Chemical Filtration Systems Frequently Asked Questions

Direct engineering answers covering PSA, PSA-PG, DBS, CA, and WGP applications, ISA-71.04 Class G1, and media types.

Which family should I use for a petrochemical control room?

Start with Fresh-Air Chemical Filtration using PSA, or High-Airflow Chemical Filtration using PSA-PG when the outdoor-air demand is larger (up to 68,000 m³/h).

Which unit is intended for data-center or server-room recirculation?

Review Recirculation Chemical Filtration. DBS and CA are the YONGFAN indoor protection routes; CA has a documented range of 850–6,800 m³/h.

When should I choose PSA-PG instead of PSA?

Choose PSA-PG when the same corrosion-control duty requires substantially more airflow per unit. The documented PSA-PG range reaches 68,000 m³/h versus 34,000 m³/h for PSA.

Which family should I use for wastewater odor exhaust?

Use Exhaust Gas Treatment with WGP. Where odor must first be captured from open tanks, pair with the supplier’s OGP collection/enclosure covers.

Can a HEPA filter replace a chemical filter?

No. HEPA filters capture particles. PSA, PSA-PG, DBS, CA and WGP use gas-phase adsorption and chemisorption media to capture airborne molecular gases.

Which YONGFAN family targets Class G1 corrosion control?

The supplier positions PSA, PSA-PG, DBS and CA around the protected-room ANSI/ISA-71.04 Class G1 target (<300 Å Cu / month).

Does WGP use only activated carbon?

No. WGP combines virgin activated carbon (iodine ≥1,000 mg/g) with chemically impregnated media so physical adsorption and chemisorption handle mixed complex gas streams.

Can I choose chemical media only from the gas name?

Not reliably. Sizing requires gas species, concentration, relative humidity, air temperature, velocity, contact time, and target media replacement interval.

08 / Application Engineering Handoff

Select a Chemical Filtration System

Connect gas analysis, airflow, environmental target, and duct pressure into one confirmed equipment schedule. Send your gas analysis data to our chemical filtration engineers.

PSA Fresh-Air (850–34,000 m³/h) PSA-PG High-Flow (1,700–68,000 m³/h) DBS & CA In-Room Recirculation WGP Exhaust Scrubber (100,000+ m³/h) ANSI/ISA-71.04 Class G1 Target ≥99% H2S / SO2 Removal
Select a Chemical System Go to Selection Center Ask an HVAC Engineer
YONGFAN impregnated honeycomb chemical filter
Direct Technical Selection Support
Media mass calculations, ISA Class G1 room sizing, and certified CAD submittals.
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