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ISO 9001 & ISO 14001 Certified
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80 + Countries Served
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≤ 5 mg/Nm³ Achievable Emission
Metallurgy & Foundry Filter Bags
Complete Baghouse Filtration Solutions for Steel Mills, Foundries, Aluminum Smelters, Ferroalloy Plants & Non-Ferrous Metal Processing — Engineered by ECOGRACE
Metallurgy and foundry filter bags face some of the most extreme operating conditions in industrial dust collection — temperatures exceeding 250 °C, highly abrasive metallic particulate, intermittent spark hazards, sub-micron metal fume, and corrosive acid gases. From the electric arc furnace (EAF) floor of a modern steel mini-mill to the shake-out deck of an iron foundry, every dust collection point demands a filter bag engineered specifically for the metallurgical environment it serves.
ECOGRACE is a specialist metallurgy and foundry filter bag manufacturer with over 25 years of direct experience supplying baghouse filtration media to steel mills, iron and aluminum foundries, ferroalloy smelters, copper/lead/zinc refineries, and precious-metal recovery operations across more than 80 countries. We don’t offer generic filter bags — we engineer application-specific filtration solutions that match the exact temperature profile, dust chemistry, particle size distribution, and cleaning cycle of each metallurgical process point.
Whether you need to upgrade an aging EAF baghouse to meet tightening EPA MACT standards, replace failing fiberglass bags in a clinker-grade ferrosilicon furnace, or commission a brand-new fume extraction system for an aluminum casthouse — ECOGRACE delivers the right filter media, the right bag construction, and the right surface treatment to maximize service life and minimize total cost of ownership.
Why Metallurgy & Foundry Dust Collection Requires Specialized Filter Bags
Standard industrial filter bags designed for cement or grain handling will fail rapidly — often within weeks — when exposed to metallurgical process conditions. The unique combination of challenges in metal processing demands purpose-built filtration media.
Extreme Temperatures
EAF off-gas can spike to 300 – 400 °C during oxygen blow. Ladle furnace fume reaches 200 – 250 °C. Ferroalloy furnace exhaust operates at 180 – 280 °C continuously. Filter bags must withstand both sustained high temperatures and rapid thermal cycling without losing tensile strength or dimensional stability.
Highly Abrasive Metallic Dust
Metal scale, slag particles, and silica sand from foundry shake-out are extremely abrasive — Mohs hardness 5 – 7. These particles erode conventional filter media at cage contact points, seam junctions, and the bag bottom within months. Metallurgy demands heavy-duty felt weights (550 – 600 g/m²) and reinforced construction.
Spark & Ember Hazards
Hot metal splashes, welding sparks, and incandescent particles are inherent to steelmaking and foundry operations. A single ember can burn through polyester or acrylic filter media instantly. Metallurgy filter bags require inherently flame-resistant fibers (LOI ≥ 28) such as Nomex, PTFE, P84, or fiberglass — never commodity polyester.
Sub-Micron Metal Fume
EAF and induction furnace operations generate metal oxide fume with primary particle sizes of 0.01 – 1.0 μm. These ultra-fine particles penetrate deep into conventional depth-filtration media, causing irreversible blinding. PTFE membrane surface filtration is essential for capturing sub-micron fume while maintaining cleanable pressure drop.
Heavy Metal & Toxic Dust
Metallurgical dust contains lead, zinc, cadmium, hexavalent chromium (Cr⁶⁺), manganese, and other regulated heavy metals. Regulatory agencies worldwide impose strict emission limits — any bag failure or bypass results in immediate compliance violations and potential facility shutdown.
CO & Explosive Atmosphere Risk
Closed and semi-closed submerged arc furnaces, blast furnace casthouse, and certain smelting operations produce carbon monoxide (CO) and combustible dust atmospheres. Anti-static filter bags with surface resistivity ≤ 10⁹ Ω are mandatory for ATEX/NFPA compliance in these environments.
Metallurgy & Foundry Filter Bags by Application
ECOGRACE provides application-specific metallurgy and foundry filter bags for every major metal processing sub-sector. Click through to explore detailed product specifications, material selection guides, and case studies for your specific industry.
Metallurgy & Foundry Filter Bag Selection Guide — By Process Point
Use the table below to quickly identify the recommended ECOGRACE filter bag specification for your specific metallurgical process. This guide covers 20+ process points across all major metal processing operations.
| Industry | Process Point | Temp (°C) | Dust Loading | Recommended Media | Surface Treatment | Anti-Static | A/C Ratio |
|---|---|---|---|---|---|---|---|
| Steel Mill | |||||||
| Steel | EAF Primary Fume | 200 – 260 | 5 – 15 g/Nm³ | Fiberglass 750 g/m² | PTFE Membrane | Optional | 0.8 – 1.0 |
| Steel | EAF Secondary (canopy) | 80 – 150 | 1 – 5 g/Nm³ | Polyester 550 g/m² | Singe + Calendar | Yes | 1.0 – 1.2 |
| Steel | BOF Primary Gas Cleaning | 180 – 250 | 10 – 30 g/Nm³ | Fiberglass 800 g/m² | PTFE Membrane + Acid Coat | No | 0.7 – 0.9 |
| Steel | Ladle / AOD Furnace | 180 – 220 | 2 – 8 g/Nm³ | Nomex 550 g/m² | Singe + Calendar | Optional | 0.9 – 1.1 |
| Steel | Sinter Plant Windbox | 120 – 180 | 3 – 10 g/Nm³ | PPS 550 g/m² | PTFE Membrane | No | 0.8 – 1.0 |
| Steel | Blast Furnace Casthouse | 150 – 200 | 2 – 5 g/Nm³ | Nomex 500 g/m² | Singe + Calendar | Yes | 1.0 – 1.2 |
| Steel | Continuous Caster | 100 – 160 | 1 – 3 g/Nm³ | Nomex 500 g/m² | W&O Repellent | No | 1.0 – 1.3 |
| Foundry | |||||||
| Foundry | Induction Furnace Melting | 160 – 200 | 3 – 10 g/Nm³ | Nomex 550 g/m² | PTFE Membrane | Yes | 0.8 – 1.0 |
| Foundry | Cupola Furnace | 200 – 260 | 5 – 15 g/Nm³ | Fiberglass 750 g/m² | PTFE Membrane | Yes | 0.7 – 0.9 |
| Foundry | Pouring / Cooling Line | 80 – 160 | 1 – 5 g/Nm³ | Nomex 500 g/m² | Singe + Calendar | Yes | 1.0 – 1.2 |
| Foundry | Shake-Out / Sand Handling | 60 – 120 | 10 – 30 g/Nm³ | Nomex 600 g/m² HD | Singe + Calendar | No | 0.8 – 1.0 |
| Foundry | Shot Blast / Grinding | Ambient | 5 – 20 g/Nm³ | Polyester 550 g/m² | Singe + Calendar | Yes | 1.2 – 1.5 |
| Aluminum Smelter | |||||||
| Aluminum | Potline GTC | 130 – 180 | 2 – 8 g/Nm³ | Fiberglass 550 g/m² | PTFE Membrane | No | 0.8 – 1.0 |
| Aluminum | Casthouse Fume | 120 – 180 | 1 – 5 g/Nm³ | Nomex 500 g/m² | W&O Repellent | No | 1.0 – 1.2 |
| Aluminum | Anode Baking Furnace | 200 – 260 | 1 – 3 g/Nm³ | PTFE Felt / Fiberglass | Acid Resistant Coat | No | 0.7 – 0.9 |
| Ferroalloy | |||||||
| Ferroalloy | FeSi SAF (Open) | 200 – 280 | 20 – 50 g/Nm³ | Fiberglass 800 g/m² | PTFE Membrane | No | 0.6 – 0.8 |
| Ferroalloy | FeCr SAF | 180 – 250 | 10 – 30 g/Nm³ | Fiberglass 750 g/m² | PTFE Membrane | No | 0.7 – 0.9 |
| Ferroalloy | SiMn / FeMn (Closed SAF) | 160 – 220 | 5 – 15 g/Nm³ | Fiberglass 750 g/m² | PTFE Membrane | Yes (mandatory) | 0.7 – 0.9 |
| Non-Ferrous Smelting | |||||||
| Non-Ferrous | Copper Flash / Bath Smelter | 200 – 260 | 2 – 10 g/Nm³ | PTFE Felt 800 g/m² | Acid Resistant | No | 0.6 – 0.8 |
| Non-Ferrous | Lead / Zinc Smelter | 160 – 200 | 3 – 10 g/Nm³ | PPS 550 g/m² | PTFE Membrane | No | 0.7 – 0.9 |
| Non-Ferrous | Nickel Laterite Kiln | 220 – 280 | 5 – 15 g/Nm³ | Fiberglass 800 g/m² | PTFE Membrane | No | 0.6 – 0.8 |
Filter Media Comparison for Metallurgy & Foundry Applications
Selecting the right filter media is the most critical decision in metallurgical baghouse design. The table below compares the five primary media types used in metal processing dust collection.
| Parameter | Nomex (Aramid) | Fiberglass | PTFE Felt | PPS (Ryton) | P84 (Polyimide) |
|---|---|---|---|---|---|
| Max Continuous Temp | 204 °C | 260 °C | 260 °C | 190 °C | 240 °C |
| Abrasion Resistance | Excellent | Poor | Fair | Good | Fair |
| Flex Fatigue Resistance | Excellent | Very Poor | Good | Good | Fair |
| Acid Resistance | Good | Fair | Excellent | Excellent | Good |
| Oxidation Resistance | Good | Good | Excellent | Poor | Good |
| Sub-Micron Fume Capture | Good (w/ membrane) | Good (w/ membrane) | Excellent (inherent) | Good (w/ membrane) | Excellent (trilobal) |
| Spark Resistance | Good (LOI 28) | Excellent (non-combustible) | Excellent (LOI 95) | Good (LOI 34) | Good (LOI 36) |
| Cost Index (1=lowest) | 3 | 2 | 7 | 4 | 6 |
| Best Metallurgy Fit | Foundry, Ladle, BF | EAF, BOF, FeSi SAF | Cu/Pb/Zn Smelter | Sinter, Zn Electrolytic | EAF Secondary, Mixed |
Global Emission Standards for Metallurgy & Foundry Operations
Metal processing facilities worldwide face increasingly stringent particulate and heavy-metal emission regulations. ECOGRACE metallurgy and foundry filter bags are engineered to meet or exceed all major international standards.
| Standard | Region | PM Limit | Heavy Metal Limits | ECOGRACE Solution |
|---|---|---|---|---|
| EU BAT-AEL (Iron & Steel BREF) | Europe | 2 – 10 mg/Nm³ | Pb ≤ 0.5, Cd ≤ 0.05 mg/Nm³ | PTFE membrane — ≤ 5 mg/Nm³ |
| US EPA NESHAP (Iron Foundries) | USA | 0.005 – 0.1 gr/dscf | Pb ≤ 0.04 mg/dscm | PTFE membrane — compliant |
| US EPA NESHAP (EAF Steelmaking) | USA | 0.0052 lb/ton steel | Various MACT limits | Fiberglass + PTFE membrane |
| China GB 28664 (Steel) | China | 10 – 20 mg/Nm³ | Pb ≤ 0.5 mg/Nm³ | Standard treatment — compliant |
| China Ultra-Low Emission (Steel) | China (key regions) | ≤ 10 mg/Nm³ | Stricter than GB 28664 | PTFE membrane — ≤ 5 mg/Nm³ |
| India CPCB (Foundries) | India | 50 – 150 mg/Nm³ | State-specific | Standard Nomex — compliant |
| World Bank / IFC EHS (Smelting) | Global (developing) | 20 – 50 mg/Nm³ | Pb ≤ 1.0, Hg ≤ 0.05 mg/Nm³ | Standard or membrane — compliant |
Customer Case Studies — ECOGRACE Metallurgy & Foundry Filter Bags in Action
Why Metal Processors Worldwide Choose ECOGRACE
25+
Years in Metals Filtration
Since 2000, ECOGRACE has specialized in filter bags for the most demanding metallurgical environments — from single-furnace foundries to integrated steel complexes with 10 000+ bag baghouses.
500+
Metal Industry Installations
Over 500 successful installations across steel mills, foundries, aluminum smelters, ferroalloy plants, and non-ferrous refineries in 80+ countries on 6 continents.
Lab
In-House Testing Laboratory
Complete in-house laboratory for tensile strength, air permeability, chemical resistance, and used-bag failure analysis. Free diagnostic service for metallurgy customers.
OEM
Compatible with All Brands
ECOGRACE manufactures exact-fit replacement filter bags for all major baghouse dust collector brands — Donaldson, Camfil, BETH, Intensiv-Filter, Scheuch, Redecam, and hundreds of OEMs.
100%
Custom Manufacturing
Every filter bag is made to order — custom diameter, length, media type, weight, surface treatment, and top/bottom configuration. No minimum order for custom sizes. Reverse engineering from sample bags available.
24/7
Technical Support
Dedicated metallurgy engineering team for remote diagnostics, media selection assistance, on-site commissioning support, and preventive maintenance planning.
Recommended Filter Media for Metallurgy & Foundry
Nomex Filter Bags
Meta-aramid up to 204 °C — best abrasion resistance for foundry & ladle furnace
Aramid Filter Bags
Nomex needle felt for high-temperature abrasive metallic dust
PTFE Filter Bags
260 °C continuous — ultimate chemical resistance for non-ferrous smelters
High Temperature Filter Bags
Fiberglass, P84 & PTFE for 200 – 280 °C metallurgical processes
Dust Collector Filter Bags
Complete range of baghouse filter bags for all temperature ranges
Baghouse Filter Bags
Pulse-jet & reverse-air baghouse replacement bags for all brands
Industrial Filter Bags
Heavy-duty for mining, power, chemical & metallurgical applications
Pulse Jet Dust Collectors
Complete baghouse systems for metallurgy & foundry dust collection
Frequently Asked Questions — Metallurgy & Foundry Filter Bags
1. What type of filter bags are best for steel mill EAF dust collection?
For electric arc furnace (EAF) primary fume extraction, the industry standard is fiberglass needle felt (750 – 800 g/m²) with PTFE membrane lamination. This combination provides the thermal stability needed for 200 – 260 °C continuous operation, non-combustibility for spark protection, and surface filtration for capturing sub-micron metal oxide fume at ≤ 5 mg/Nm³. ECOGRACE steel mill filter bags with PTFE membrane consistently achieve 24+ month service life in EAF applications. For EAF secondary (canopy hood) collection at lower temperatures, anti-static polyester or Nomex is more cost-effective.
2. How long do filter bags last in foundry applications?
Filter bag service life in foundry operations varies significantly by process point. Melting area (induction/cupola): 24 – 36 months with Nomex + PTFE membrane. Shake-out and sand handling: 18 – 24 months with heavy-duty Nomex 600 g/m² (high abrasion). Shot blasting and grinding: 24 – 36 months with anti-static polyester. Key factors affecting life include dust loading, particle abrasiveness, temperature consistency, and pulse cleaning maintenance. ECOGRACE offers free used-bag laboratory analysis to predict remaining service life and optimize replacement schedules.
3. Why is PTFE membrane important for metallurgy filter bags?
PTFE membrane lamination transforms a depth-filtration felt into a surface filtration medium. In metallurgy, this is critical because: (1) Sub-micron metal fume from EAF, induction furnaces, and smelting operations penetrates conventional felt and causes irreversible blinding. (2) The PTFE membrane captures 99.99 % of particles ≥ 0.1 μm on the membrane surface, allowing clean pulse-jet release. (3) Operating ΔP remains stable at 600 – 900 Pa versus 1 500 – 2 500 Pa without membrane. (4) In ferroalloy applications, membrane filtration maximizes silica fume recovery — a revenue-generating by-product worth $200 – $800/ton.
4. Do foundry filter bags need anti-static treatment?
Yes — anti-static treatment is strongly recommended for most foundry applications and is mandatory for certain environments. Metallic dust from grinding, shot blasting, and melting can be combustible. Electrostatic charge on filter bags can be an ignition source. Anti-static Nomex or polyester filter bags (with conductive fibers at 2 – 5 % by weight) achieve surface resistivity ≤ 10⁹ Ω, meeting ATEX Zone 22 and NFPA 652 requirements. For ferroalloy closed SAF environments with CO gas, anti-static is absolutely mandatory.
5. What emission levels can metallurgy filter bags achieve?
With proper media selection and baghouse design, ECOGRACE metallurgy filter bags achieve: Standard singed/calendered felt: 10 – 30 mg/Nm³. PTFE membrane laminated: ≤ 5 mg/Nm³ (steady state) and ≤ 10 mg/Nm³ during pulse cleaning. These levels comply with EU BAT-AEL for iron and steel (2 – 10 mg/Nm³), US EPA NESHAP MACT, and China Ultra-Low Emission requirements (≤ 10 mg/Nm³). For heavy metals (Pb, Cd, Cr, Hg), PTFE membrane bags prevent fine particulate penetration, ensuring compliance with stack testing requirements.
6. Can ECOGRACE supply filter bags for any baghouse brand used in steel mills?
Yes — ECOGRACE manufactures exact-fit replacement filter bags compatible with all major industrial dust collector brands used in the metals industry, including Donaldson Torit, Camfil APC, BETH Filter, Intensiv-Filter, WAM, Scheuch, Redecam, FLSmidth, GEA, and hundreds of regional OEMs. We offer 100 % custom fabrication — provide bag dimensions, cage diameter, and operating conditions, and we manufacture exact-fit metallurgy filter bags. Reverse engineering from sample bags is also available.
7. How do I select the right filter media for my metallurgical process?
Selection depends on four primary factors: (1) Operating temperature: Below 190 °C → Nomex or PPS; 190 – 260 °C → Fiberglass, P84, or PTFE; Above 260 °C → PTFE felt or fiberglass with cooling. (2) Chemical environment: Acid gases (SO₂, HCl) → PPS or PTFE; Alkaline dust → Nomex or Fiberglass; Oxidizing → PTFE (not PPS). (3) Dust abrasiveness: High abrasion (foundry sand, slag) → Aramid/Nomex for flex resistance; Low abrasion (metal fume) → Fiberglass with membrane. (4) Safety: Combustible dust/CO → anti-static mandatory. Contact ECOGRACE for personalized recommendations.
8. What is the price range for metallurgy and foundry filter bags?
ECOGRACE metallurgy and foundry filter bags are priced based on media type, weight, surface treatment, dimensions, and quantity. Indicative ranges: Nomex standard (500 g/m²): $8 – $18/pc. Fiberglass + PTFE membrane (750 g/m²): $12 – $28/pc. PTFE felt (800 g/m²): $25 – $55/pc. PPS + PTFE membrane (550 g/m²): $10 – $22/pc. Despite higher upfront cost, PTFE membrane bags deliver 20 – 40 % lower total cost of ownership over 3 years due to extended life and reduced energy consumption. Request a detailed quotation for your specific requirements.
What special considerations apply to aluminum smelter filter bags?
Aluminum smelter baghouses face a unique challenge: hydrogen fluoride (HF) gas generated by electrolytic reduction. HF attacks most filter media unless bags are pre-coated with fresh alumina that adsorbs HF before reaching the filter surface. ECOGRACE aluminum smelter filter bags are designed for this dual function — fluoride capture/recycling and particulate filtration. PTFE membrane on fiberglass substrate is preferred for potline Gas Treatment Centers (GTCs), providing HF adsorption efficiency and ultra-low particulate emission. Captured fluoride-rich alumina is recycled to reduction cells, recovering 98+ % of fluoride emissions.
How does silica fume recovery work in ferroalloy plants?
Ferrosilicon and silicon metal SAFs generate massive quantities of amorphous micro-silica (SiO₂) fume — 20 – 50 g/Nm³ with primary particle sizes of 0.1 – 0.5 μm. This silica fume is a high-value by-product ($200 – $800/ton) used in concrete, refractories, and ceramics. The key to maximizing recovery is preventing silica fume from penetrating the felt. ECOGRACE ferroalloy filter bags with PTFE membrane achieve ≥ 99.99 % capture, keeping silica on the membrane surface for clean pulse-release collection. This maintains stable ΔP, extends bag life, and produces higher-purity silica commanding premium pricing.
What causes premature filter bag failure in steel mills?
Most common causes: (1) Temperature excursions — EAF oxygen blow spikes to 300+ °C. Solution: temperature interlock with bypass damper. (2) Spark/ember damage — hot metal splashes burn pinholes. Solution: spark arrestor screen or inherently flame-resistant media. (3) Sub-micron fume blinding — metal oxide fume penetrates conventional felt. Solution: PTFE membrane. (4) Cage damage — bent/corroded wires abrade bags internally. Solution: regular cage inspection. (5) Improper pulse cleaning — excessive or insufficient pressure. Solution: calibrate to 4 – 6 bar with proper valve timing per ECOGRACE recommendations.
Can ECOGRACE provide on-site technical support for metallurgy installations?
Yes — ECOGRACE offers comprehensive on-site support: (1) Pre-installation survey — assess baghouse configuration, measure cage dimensions, review operating data. (2) Installation supervision — ensure correct snap band seating, cage fit, and commissioning. (3) Commissioning optimization — pulse calibration, ΔP baseline, emission verification. (4) Preventive maintenance audits — periodic inspections with ΔP trending and bag sampling. (5) Failure root-cause analysis — laboratory identification of failure mechanisms with corrective recommendations. Contact our metallurgy team to discuss your requirements.
Get Expert Filtration Solutions for Your Metallurgy & Foundry Operation
Tell us your process conditions — temperature, dust type, gas volume, current baghouse brand — and our metallurgy engineering team will provide a detailed technical proposal within 48 hours.
Email: [email protected] | Phone: +86 135 8806 5995