Dust Collectors Baghouses and Cartridge Collectors

Overview Dust Collection Collectors Fabric Filters Trends

Grain Loading Industrial 0.1 to 100 grains / ft 3 –100 to 100,000 times 5 grains / ft 3 2,000 CFM for 365 days 750,857 lbs 150 lbs in < 2 hours HVAC grains / ft 3 2,000 CFM for 365 days 150 lbs Industrial Ventilation – –Design, 28 th Edition, $ 140

Media Velocity Industrial Filter Rate / Air to Cloth –5 FPM –0.06 mph –1 hour to walk a football field HVAC 2,000 CFM through… –32 ft 2 Pleat> 60 FPM –100 ft 2 Box20 FPM –200 ft 2 HEPA10 FPM

Purpose of Pollution Control Comply - Collect - Protect COMPLY with Regulations –EPA and OSHA COLLECT Product PROTECT Resources –Equipment and Occupants

Three C’s of Pollution Control Capture Convey Collect

Pollution Control System Pickup Points –Emission Source Ductwork Dust Collector Removal System Fan Exhaust / Return

Pollution Control Components Pickup Points –Emission Source Ductwork Dust Collector Removal System Fan Exhaust / Return

Pollution Control Components Dust Collector Types –Electrostatic Precipitators (ESP) –Wet Collectors –Dry Centrifugal –Fabric Collectors

Pollution Control Components Dust Collector Types –Electrostatic Precipitators (ESP) –Wet Collectors –Dry Centrifugal –Fabric Collectors

Fabric Collectors Baghouse –Shaker - Cleans Off Line –Reverse Air - Cleans Off Line –Pulse Jet - Cleans On Line

Fabric Collectors Baghouse –Shaker - Cleans Off Line –Reverse Air - Cleans On Line –Pulse Jet - Cleans On Line

Fabric Collectors Baghouse –Shaker - Cleans Off Line –Reverse Air - Cleans On Line –Pulse Jet - Cleans On Line Cartridge Collector –Up flow –Cross flow –Down flow / Parallel flow

Fabric Collectors Baghouse –Shaker - Cleans Off Line –Reverse Air - Cleans On Line –Pulse Jet - Cleans On Line Cartridge Collector –Up flow –Cross flow –Down flow / Parallel flow

Pulse Jet Components Inlet Distribution (1) Hopper Housing (2) Plenum (3) Tubesheet (4) Cleaning System –Header –Blow Pipe –Venturi

Cartridge Collector Components Inlet Distribution Housing Hopper Tubesheet Plenum Cleaning System

Collector Considerations Process Conditions –Temperature –Pressure –Moisture –Chemistry –Grain Load Dust Properties –Particle Size –Particle Shape –Explosivity / Flamability –Agglomeration –Abrasive Space Constraints –Footprint –Height Capital Cost Operating Costs –Media –Compressed Air –Energy /  P AIR FLOW

FiberTensile Abrasio n Resist Acid Resist Alkali Resist Burns Temp F (Cont) Temp F (Surge) CottonGood PoorGoodYes PolypropyleneExcellent Yes NylonExcellent PoorExcellentYes WoolPoorFairGoodPoorNo Homopolymer Acrylic Good Very GoodFairYes Copolymer Acrylic AverageFairGoodFairYes Polyester Excelle nt Fair Yes Aramid Very Good ExcellentFairGoodNo PTFEAverageFairExcellent No GlassExcellentFairGoodFairNo Ryton Very Good Excellent Very GoodNo P84 Very Good ExcellentVery GoodFairNo500?550?

Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR Bags4 to 8 fpm Pleated2 to 6 fpm

Example Application 1,880 CFM through 10” line to Model 25S(6)-10 4” Line 0.09 ft CFM 6” Line 0.20 ft CFM 5” Line 0.14 ft CFM 3” Line 0.05 ft CFM 1,880 CFM 0.47 ft 2 10” Line at 3,450 FPM 9” Line at 4,260 FPM

Inlet Duct = 11” Round = 0.66 ft 2 Inlet Velocity = 1,880 CFM / 0.66 ft 2 = 2,850 FPM Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR

Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR

Collector Considerations

Air Velocities –Inlet –Can / Interstitial –Media / ACR ft 2 42” Can Velocity = 1,880 CFM / ft 2 = 155 FPM

Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR 42” Bag Bottom Area = Qty *  * Radius 2 = 25 * 3.14 * (3”) 2 = 4.9 ft 2 Interstitial Area = ft 2 = 7.35 ft 2 Interstitial Velocity = 1,880 / 7.35 = 255 FPM Interstitial = 255 / 155 = 1.6 x Can Velocity

Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR

Collector Considerations Air Velocities –Inlet –Can / Interstitial –Media / ACR Bag Area = Qty *  * Diameter * Length = 25 * 3.14 * 6” * 120” = 393 ft 2 Media Velocity = 1,880/ 393 = 4.8 FPM

Collector Considerations Air Velocities –Inlet2,850 FPM –Can155 FPM –Interstitial255 FPM –Media / ACR4.8 FPM –Exhaust2,500 FPM

Trends New Equipment –High inlets –ePTFE membrane fabric –Pleated filters –Multi-module for off-line cleaning and on-line maintenance Baghouse Modifications –NFPA compliance –ESP / Shaker / Reverse Air conversions to Pulse Jet –Pleat conversions