Corrosion-Resistant PPS Filter Bags for Industrial Dust

 Introduction 

Referred to as Polyphenylene Sulfide Filtration Bags (PPS is a high-performance polymer defined by ISO 1043-1) and Chemical-Resistant High-Temp Filter Bags, these industrial filtration solutions are designed to thrive in aggressive chemical environments where both corrosion resistance and thermal stability are non-negotiable. Constructed from 100% virgin PPS (polyphenylene sulfide) needle felt—sourced from leading polymer suppliers like Toray and Solvay—these filter bags provide exceptional resistance to acids, alkalis, and organic solvents, even in high-temperature operations where moisture amplifies chemical attack.

Operating within a continuous temperature range of 160°C to 190°C (320°F to 374°F) with short-term tolerance up to 200°C (392°F), these corrosion-resistant PPS bags outperform acrylic (only resists weak acids) and standard polyester (degrades in pH <4 or >10) filters by a wide margin. Their unique chemical structure—phenylene rings linked by sulfide groups—creates a barrier against hydrolysis (even in 90% relative humidity) and chemical degradation, ensuring long-term reliability in processes like sulfuric acid production, where conventional filters fail in 3–6 months.

 Features 

Chemical and Material Properties

Corrosion Resistance: Withstands exposure to strong acids (pH 2–4, e.g., 30% sulfuric acid, 20% hydrochloric acid), alkalis (pH 10–12, e.g., 10% sodium hydroxide, 5% potassium hydroxide), and organic solvents (e.g., methanol, acetone, toluene) per ASTM D5432 chemical resistance tests—no fiber discoloration or strength loss after 1000 hours of immersion.

Filtration Efficiency: Achieves >99.9% particle retention for 0.5–20μm particles (tested with ISO 12103-1 A1 ultrafine dust), meeting M16 filtration standards (EN ISO 16890) for fine chemical dusts like ammonium nitrate and pesticide powders.

Thermal Stability: Maintains ≥90% of original tensile strength in continuous operation at 190°C, with minimal strength loss (≤5%) after 10,000 hours of exposure—far exceeding PTFE-blended filters, which lose 10% strength in the same period.

Hydrolysis Resistance: Performs reliably in saturated steam environments (100°C, 100% RH) for 500+ hours, avoiding the premature failure common in polyester bags (which hydrolyze in 100 hours of steam exposure).

Operational Specifications

Maximum Continuous Temperature: 190°C (374°F)

Chemical Compatibility: Resists 90% of industrial chemicals, including sulfuric acid (H₂SO₄), nitric acid (HNO₃), sodium hydroxide (NaOH), chlorine gas (Cl₂), and ethylene glycol—critical for chemical manufacturing where multiple chemicals are present.

Pressure Drop: Initial differential pressure <0.6 bar at 1.2 m/min airflow velocity (standard for chemical plant baghouses), with pressure drop increase limited to <0.3 bar annually (due to low dust cake adhesion).

Seam Construction: Chemical-resistant welded seams (using PPS hot-melt adhesive, melting point 280°C) with PPS thread reinforcement (20/2 tex count) to prevent chemical ingress—seams are tested for leakage with 100% helium leak detection (per ISO 15797).

 Application Cases 

Corrosion-Resistant PPS Filter Bags are essential in chemically aggressive industrial processes, where even minor filter failure can lead to regulatory violations or equipment damage:

Chemical Manufacturing: Filters dust from sulfuric acid production (oleum decomposition stages) and chlorine gas processing (electrolysis of brine), resisting acid mist corrosion that would degrade polyester bags in 3 months. A chemical plant in Texas reported 18-month service life with these PPS bags, vs. 4 months for acrylic.

Wastewater Treatment: Captures sludge particles (with heavy metals like cadmium and chromium) in chemical precipitation processes, withstanding caustic cleaning cycles (10% NaOH at 80°C) used to remove fouling.

Pulp and Paper: Manages bleach plant emissions containing chlorine dioxide (ClO₂) and hydrogen peroxide (H₂O₂)—chemicals that break down standard filters. These PPS bags comply with EPA 40 CFR Part 63 Subpart BB (pulp and paper MACT standards).

Electroplating Facilities: Controls heavy metal dust (e.g., nickel, copper, zinc) and acid fumes (e.g., chromic acid) from plating baths, complying with EPA National Emission Standards for Hazardous Air Pollutants (NESHAP) for electroplating.

 Product Advantages 

These PPS filter bags offer significant, data-driven benefits over conventional filtration materials (acrylic, polyester, glass fiber):

Longevity: 2–3 times longer service life than acrylic bags in chemical environments (18–24 months vs. 6–8 months), reducing replacement frequency and labor costs. A wastewater treatment plant in Florida saved $45,000 annually in filter changeout labor.

Total Cost Savings: 30% lower total cost of ownership over 5 years compared to PTFE filters—while PTFE bags cost 300 each (vs. 180 for PPS), PPS requires 50% fewer changeouts, leading to $12,000 savings for a 500-bag baghouse.

Process Compatibility: Performs reliably in both acidic and alkaline environments (pH 2–12), eliminating the need for material switching in processes with variable pH (e.g., batch chemical production).

Regulatory Compliance: Meets EPA MACT standards (e.g., 40 CFR Part 63 Subpart CC for chemical manufacturing) and EU REACH regulations (no restricted substances), avoiding costly fines for non-compliance.

 Quality 

Our specialized customization ensures optimal performance in corrosive environments, with a focus on chemical compatibility and process fit:

Chemical Analysis: Laboratory testing of process gases (via gas chromatography-mass spectrometry, GC-MS) and dust (via X-ray fluorescence, XRF) to determine optimal PPS formulation—for example, adding 5% PTFE fibers for enhanced solvent resistance in pharmaceutical chemical processes.

Engineering Design: Customizes dimensions (diameters 150–300mm, lengths 2000–6000mm) and filter area (calculated based on dust loading, typically 5–10 g/m³) to avoid premature clogging. For a high-dust electroplating facility, we designed 250mm diameter bags to increase surface area by 30%.

Membrane Options: Offers optional ePTFE membrane lamination (0.2μm pore size) for enhanced submicron particle capture (<1μm) in sensitive applications (e.g., pharmaceutical API production). The membrane increases filtration efficiency to 99.99% but adds 20% to cost.

Testing Protocol: Samples undergo 500-hour chemical immersion testing in customer-specific process fluids (e.g., 20% sulfuric acid for a fertilizer plant), followed by tensile strength and filtration efficiency testing to validate resistance.

Production Quality: Manufactured in ISO 9001:2015 facilities with 100% leak testing (using 0.5 bar compressed air) and chemical exposure validation—each bag is tagged with a batch number for traceability, and test reports are provided with every shipment.