dust collectors baghouses and cartridge collectors
TRANSCRIPT
Dust CollectorsBaghouses and Cartridge Collectors
Overview
• Dust Collection
• Collectors
• Fabric Filters
• Trends
Grain Loading
Industrial• 0.1 to 100 grains / ft3
– 100 to 100,000 times
• 5 grains / ft3
• 2,000 CFM for 365 days
• 750,857 lbs• 150 lbs in < 2 hours
HVAC• 0.001 grains / ft3
• 2,000 CFM for 365 days• 150 lbs
• Industrial Ventilation– www.ACGIH.org– Design, 28th 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 ft2 Pleat > 60 FPM– 100 ft2 Box 20 FPM– 200 ft2 HEPA 10 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
FiberTensil
e
Abrasion
Resist
AcidResist
Alkali Resist
BurnsTemp
F (Cont)
Temp F (Surge
)
Cotton Good Good Poor Good Yes 180 200
Polypropylene Excellent Excellent Excellent Excellent Yes 170 200
Nylon Excellent Excellent Poor Excellent Yes 200 250
Wool Poor Fair Good Poor No 200 230
HomopolymerAcrylic
Good GoodVery Good
Fair Yes 260 284
CopolymerAcrylic
Average Fair Good Fair Yes 230 248
PolyesterExcelle
ntExcellen
tFair Fair Yes 275 300
AramidVery Good
Excellent Fair Good No 375 425
PTFE Average Fair Excellent Excellent No 450 500
Glass Excellent Fair Good Fair No 500 550
RytonVery Good
Excellent ExcellentVery Good
No 375 425
P84Very Good
ExcellentVery Good
Fair No 500? 550?
Collector Considerations
• Air Velocities– Inlet
– Can / Interstitial
– Media / ACR• Bags
4 to 8 fpm• Pleated
2 to 6 fpm
Example Application
1,880 CFM through 10” line to Model 25S(6)-10
4” Line0.09 ft2
350 CFM
6” Line0.20 ft2
785 CFM
5” Line0.14 ft2
545 CFM
3” Line0.05 ft2
200 CFM
1,880 CFM0.47 ft2
10” Line at 3,450 FPM9” Line at 4,260 FPM
Inlet Duct = 11” Round = 0.66 ft2
Inlet Velocity = 1,880 CFM / 0.66 ft2 = 2,850 FPM
Collector Considerations
• Air Velocities– Inlet
– Can / Interstitial
– Media / ACR
Collector Considerations
• Air Velocities– Inlet
– Can / Interstitial
– Media / ACR
Collector Considerations
Collector Considerations
• Air Velocities– Inlet
– Can / Interstitial
– Media / ACR
12.25 ft242”
42”
Can Velocity = 1,880 CFM / 12.25 ft2 = 155 FPM
Collector Considerations
• Air Velocities– Inlet
– Can / Interstitial
– Media / ACR
42”
42”
Bag Bottom Area = Qty * * Radius2
= 25 * 3.14 * (3”)2
= 4.9 ft2
Interstitial Area = 12.25 - 4.9 ft2
= 7.35 ft2
Interstitial Velocity = 1,880 / 7.35 = 255 FPMInterstitial = 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 ft2
Media Velocity = 1,880/ 393 = 4.8 FPM
Collector Considerations
• Air Velocities– Inlet 2,850 FPM– Can 155 FPM– Interstitial 255 FPM– Media / ACR 4.8 FPM– Exhaust 2,500 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