Transcript Slide 1

Engineering Fiber Blends for
Enhanced Filtration Efficiency
Use of Micro Denier Fibers to
Improve Pulse Jet Baghouse
Performance
Keith Ogilvie
Director, National Filter Media
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Abstract
When conventional needle felts provide inadequate filtration
efficiency, what affordable options are available? This paper will
highlight some intriguing designs that have been developed by
blending various fibers, both homogeneously and in composite
construction, to achieve higher filtration efficiencies.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Briefly as a Cursory Description…
•A Homogenous blend is one that consists of uniform blending of
multiple fibers either of different denier sizes, cross section, and/or of
different fiber types.
•A Composite construction is one that consists of a stratification or
laying of fibers of different denier sizes, cross section, and/or of
different fiber types on the face side (facing the dust stream) versus
the back side of the needle felt.
•As one can imagine, there are many variations that are available in
the construction of needle felt.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
General Evolution of Blended Needle Felts
HISTORICALLY
WOVENS for Shaker & Reverse Air Baghouses
Late 1960s
NEEDLEFELTS INTRODUCED (3.0 DENIER)
Early 1980s
BOOM of PJBH - 1.5 AND 3.0 DENIER BLENDS
Mid 1980s
TEFAIRE® first blended fiber/felt. PTFE + FG
Early 1990s
100% 1.5 DENIER IN REGULAR PRODUCTION
Mid 1990s
100% 0.7 DENIER IN REGULAR PRODUCTION
Present
MICRO-DENIER CAP PRODUCTS
Depth v. Surface Filtration
Surface Filtration
ePTFE Membrane Laminates
Fiber Caps
Engineering Fiber Blends for
Enhanced Filtration Efficiency
What about Needle Felt Finishes?
Though this presentation deals
with fiber blends, it is important to
recognize that various chemical
treatments and surface finishes
might provide enhanced
performance characteristics even
beyond blends as in the case of
ePTFE membranes, which are
generally recognized as the
PM2.5/MACT for emissions.
PTFE - Intrinsic™
v.
ePTFE-Membrane
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Perspective
•Development of fine/micro denier fibers (defined as having a
fiber diameter of less than 10 microns) and fibers with unique
cross-sections are available not only for low temperature fibers
but now available for most high temperature fibers as well.
•Improved needle felting techniques and machinery has
enabled the proper processing of finer or micro denier fibers
into new and distinctive constructions.
•More stringent emission regulations have created the need for
more filtration efficient products.
•Better understanding by the Market of the “Cost/Performance”
or “True Value” of higher performance needle felts allows endusers to see a payback or benefit for using these products.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
What is Denier?
Denier is Weight per unit Length (linear
density) measure of a continuous filament
or yarn, used traditionally in textile industry.
Denier = The weight in Grams of 9,000
meters of fiber. Therefore lower the denier
number, finer the material; and higher the
denier number, coarser the material.
dtex = In most countries other than the US,
“denier” has been replaced by the Tex
system. So, fiber is measured by the
weight in Grams of 1,000 meters.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
llustration of the Length, in Miles,
of 1 Pound of Fiber
6000
5000
4000
3000
2000
1000
0
0.5
1
1.5
2
2.5
3
Denier
3.5
4
4.5
Fiber Comparison Chart
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Specific Diameter
Diameter
Diameter
Fiber Type
Gravity Microns Denier Microns Denier Microns Denier
Polypropylene 0.91
10
0.64
13
1.09
18
2.08
Nylon
1.14
10
0.81
13
1.36
18
2.61
Acrylic
1.15
10
0.81
13
1.36
18
2.61
Polyester
1.38
10
0.98
13
1.65
18
3.16
Aramid
1.38
10
0.98
13
1.65
18
3.16
PPS
1.38
10
0.98
13
1.65
18
3.16
P84
1.41
10
0.99
13
1.68
18
3.22
PTFE
2.3
10
1.56
13
2.24
18
5.04
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Comparison of Standard
and Micro Denier Fibers
Standard 2.25 Denier Fiber
0.7 Micro Denier Fiber
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Fiber Cross-Section
Blended Designs Can Incorporate Unique
Fiber Cross-Sections
Y-Shaped CrossSection of P84® Fiber
Round Cross-Section
of PPS Fiber
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Illustration of Layered
Composite Construction
Dirty Air
Surface Layer typically of
finer denier fibers
Felt Substrate
Clean Air
Structure of Micro-Maxx® (Denier Mixture) PPS Felt
With Torcon® PPS Fibers
Sketch of Micro-Maxx® with Torcon® PPS fibers
Torcon® 0.9d
Torcon® 2.7d
Mixed Top Batt
Enhances the collection performance
Torcon®7.0d
Bottom Batt
Gas stream
Results of Micro-Maxx® PPS felt
The diameter of Torcon® PPS fibers
Torcon® Micro-Maxx® 0.9d（9.7μｍ）
1．Extend the useful lifetime of filter bag
2．Lower emission v. traditional felt
Torcon® Std. 2.7d（14.5μｍ）
Torcon® Coarse 7.0d
（27μm）
Cross-section of the Micro-Maxx® PPS Felt
v.
Traditional PPS Felt Structure
Micro-Maxx® Felt with
Torcon® PPS Fibers
Traditional PPS Felt
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Micro-Denier Felts
PM 2.5 Efficiency Testing
ASTM D6830-02
~35% Lower Emissions
Smaller particles captured
~45% Reduction in Pulse Cycles
Required to maintain pressure drop
~50% Less Dust Penetration
Increasing filter bag life
~30% Energy Savings
Due to reduced number of pulses
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Polyester Needle Felt
Polyester MicroMaxx®
Standard
Polyester
Face Side
0.7 denier polyester
2.25 denier
polyester
Scrim
Spun polyester
Spun polyester
Back Batt
2.25 denier
polyester
2.25 denier
polyester
Weight
540 g/m2
540 g/m2
Permeability
20 CFM
30 CFM
Southern Felt Company, Inc.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Polyester Micro-Maxx®
0.0001146
Grains / Dry Standard Cubic Feet
0.00012
0.00011
0.00010
0.00009
0.00008
0.00007
0.00006
0.00005
0.00004
0.00003
0.00002
0.0000095
0.00001
0.00000
MicroFelt™
Southern Felt Company, Inc.
Standard Polyester
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Homopolymer Acrylic
Needle Felt
HPA MicroMaxx®
Standard HPA
Face Side
0.5 denier Dolanit
2.5 denier Dolanit
Scrim
Spun Dolanit
Spun Dolanit
Back Batt
2.5 denier Dolanit
2.5 denier Dolanit
Weight
540 g/m2
540 g/m2
Permeability
20 CFM
30 CFM
Southern Felt Company, Inc.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Homopolymer Acrylic
Micro-Maxx®
Grains / Dry Standard Cubic Feet
0.00005
0.0000421
0.00004
0.00003
0.0000226
0.00002
0.00001
0
MicroFelt™
Southern Felt Company, Inc.
Standard
Engineering Fiber Blends for
Enhanced Filtration Efficiency
P84® Needle Felt
P84® MicroMaxx®
Standard P84®
Face Side
0.9 denier P84®
2 denier P84®
Scrim
Spun P84®
Spun P84®
Back Batt
2 denier P84®
2 denier P84®
Weight
475 g/m2
475 g/m2
Permeability
25 CFM
30 CFM
Southern Felt Company, Inc.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
P84® Polyimide
Micro-Maxx®
0.0000478
Grains / Dry Standard Cubic Feet
0.000055
0.000050
0.000045
0.000040
0.000035
0.000030
0.000025
0.000020
0.000015
0.0000053
0.000010
0.000005
0.000000
MicroFelt™
Southern Felt Company, Inc.
Standard P84
Engineering Fiber Blends for
Enhanced Filtration Efficiency
PPS Needle Felt
PPS Micro-Maxx®
Standard PPS
Face Side
0.9 denier PPS
2.7 denier PPPS
Scrim
Spun PPS
Spun PPS
Back Batt
2.7 denier PPS
2.7 denier PPS
Weight
540 g/m2
540 g/m2
Permeability
25 CFM
30 CFM
Southern Felt Company, Inc.
Engineering Fiber Blends for
Enhanced Filtration Efficiency
PPS Micro-Maxx®
0.0001242
0.00013
Grains / Dry Standard Cubic Feet
0.00012
0.00011
0.00010
0.00009
0.00008
0.00007
0.00006
0.00005
0.00004
0.0000211
0.00003
0.00002
0.00001
0.00000
MicroFelt™
Southern Felt Company, Inc.
Standard PPS
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Micro-Maxx®
Outlet Particle Emission Testing
0.0003
0.00025
0.0002
grams/dry standard cubic
0.00015
meter
0.0001
0.00005
0
ePTFE
Membrane
MicroFelt
Acrylic Coated
Polyester
Polyester/P84
Cap
Note: Test dust particle size distribution: 77% less than 2.5 microns
Southern Felt Company, Inc.
Polyester
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Summary of Benefits
•High separation efficiency
•Low dust penetration
•Excellent throughput
•Low residual dust cakes
•Lower operating costs
•Ambient and hot gas needle felts available
•Affordable v. ePTFE Membrane
Engineering Fiber Blends for
Enhanced Filtration Efficiency
Acknowledgements
Southern Felt Company, Inc.