EPA/600/ETV-10/023

                                April 2010
Environmental Technology Verification


Baghouse Filtration Products
W.L. Gore & Associates, Inc.
L3650 Filtration Media
(Tested November-December 2009)
                Prepared by
      RTI International



  HRTI
  INTERNATIONAL
                        ETS Incorporated
           Under a Cooperative Agreement with
           U.S. Environmental Protection Agency
            wEPA
             ET/ ET/

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           THE ENVIRONMENTAL TECHNOLOGY VERIFICATION
                                      PROGRAM
                                  E
             
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The Air Pollution Control Technology Center (APCT Center) is operated by RTI International* (RTI), in
cooperation with EPA's National Risk Management Research Laboratory (NRMRL). The APCT Center
evaluates the performance of baghouse  filtration  products (BFPs) used primarily to control PM25
emissions (i.e.,  particles 2.5  urn and smaller in aerodynamic diameter).  This verification statement
summarizes the test results for W.L. Gore & Associates, Inc.'s L3650 filtration media.

VERIFICATION TEST DESCRIPTION

All tests were performed in accordance with the APCT Center draft Generic Verification Protocol for
Baghouse Filtration Products, available at http://www.epa.gov/etv/pubs/05_vp_bfp.pdf  The protocol is
based on and describes modifications to the equipment and procedures described in Verein Deutscher
Ingenieure  (VDI)  3926,  Part  2,  Testing of Filter Media for  Cleanable Filters under  Operational
Conditions, December 1994.  The VDI document is available from Beuth Verlag GmbH, 10772 Berlin,
Germany.  The protocol  also includes requirements for quality management and  QA, procedures for
product selection, auditing of the test laboratories, and the test reporting format.

Outlet particle  concentrations from a  test fabric  were measured with  an impactor equipped  with
appropriate substrates to filter and measure PM2s within the dust flow.  Outlet particle concentrations
were  determined  by weighing the mass  increase of dust collected in each impactor  filter stage and
dividing by the gas volumetric flow through the impactor.

Particle size was measured while  injecting the  test dust into  the  air upstream of the baghouse filter
sample.  The test dust was dispersed into the flow using a brush-type dust feeder.  The particle size
distributions in the air were determined both upstream and downstream of the test filter fabric to provide
accurate results for penetration through the test filter of PM25.  All tests were performed using a constant
18.4  ± 3.6 g/dscm (8.0 ± 1.6  gr/dscf) loading rate,  a  120 ± 6.0 m/h (6.6 ± 0.3  fpm) filtration velocity
[identical to gas-to-cloth ratio (G/C**)], and aluminum  oxide test dust with a measured mass mean
aerodynamic diameter maximum of 1.5 um (average of three impactor runs). All BFPs are tested in their
initial (i.e., clean) condition.

Each of the three test runs consisted of the following  segments:

•  Conditioning period—10,000 rapid-pulse cleaning cycles

•  Recovery period—30 normal-pulse cleaning cycles
•  Performance test period—6-hour filter fabric test period with impactor.

VERIFIED TECHNOLOGY DESCRIPTION

W.L.  Gore & Associates, Inc. provided the following information about their product.  The  L3650 is a
membrane /  fiberglass fabric laminate with a weight of 22 oz/yd2 (746  g/m2) and used in both GORE®
Filtration Products and PRISTYNE® Filter Media Type 6250.  Figure  1 is a photograph of the  fabric.
Sample material was received  as nine 46 x 91 cm (18 x 36 in.) swatches marked with the manufacturer's
model number, year and month of manufacture,  and cake side.  Three of the swatches were selected at
random for preparing three test specimens  150 mm (5.9 in.) in diameter.
* RTI International is a trade name of Research Triangle Institute.
"Filtration velocity and gas-to-cloth ratio are used interchangeably and are defined as the gas flow rate divided by
the surface area of the cloth.

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       W.L Gore
       PC# L3650
       Gore™ Membrane Fiberglass
      Figure 1.  Photograph of W.L. Gore & Associates, Inc.'s L3650 filtration media.

VERIFICATION OF PERFORMANCE

Verification testing of the W.L. Gore & Associates, Inc.'s L3650 filtration media was performed during
the period of November 30, 2009, to December 8, 2009, for standard test conditions at the test facility of
ETS Incorporated, 1401 Municipal Road NW, Roanoke, VA 24012.  Test conditions are listed in Table 1.
The overall test results summarized in Table 2 represent the averages of three individual tests.

The APCT Center quality manager has reviewed the test results and the quality control (QC) data and has
concluded that the data quality objectives given in the generic verification protocol and test/QA plan have
been attained.

This verification  statement addresses five aspects of filter fabric performance:  filter  outlet PM2s
concentration, filter outlet total mass concentration, pressure drop, filtration cycle time, and mass gain on
the filter fabric. Users may wish to consider other performance parameters, such as temperature, service
life, and cost when selecting a filter fabric for their application.

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           Table 1.  Test Conditions for Baghouse Filtration Products
       Brand/Model: W.L. Gore & Associates, Inc.'s L3650 Filtration Media
Test Parameter
Dust concentration
Filtration velocity (G/C)
Pressure loss before cleaning
Tank pressure
Valve opening time
Air temperature
Relative humidity
Total raw gas stream flow rate
Sample gas stream flow rate
Number of cleaning cycles
During conditioning period
During recovery period
Performance test duration
Value
18.4 ± 3.6 g/dscm (8.0 ± 1 .6 gr/dscf)
120±6m/h(6.6±0.3fpm)
1, 000 ±12 Pa (4 ±0.05 in. w.g.)
0.5 ± 0.03 MPa (75 ± 5 psi)
50 ± 5 ms
25 ± 2 °C (77 ± 4 °F)
50 ± 1 0%
5.8 ± 0.3 m3/h (3.4 ± 0.2 cfm)
1.13 ± 0.06 m3/h (0.67 ± 0.03 cfm)

10,000 cycles
30 cycles
6h±1 s
      Table 2. Baghouse Filtration Product Three-Run Average Test Results
            for W.L. Gore & Associates, Inc.'s L3650 Filtration Media
Verification Parameter
Outlet particle concentration at standard conditions3
PM25, g/dscm
(gr/dscf)
Total mass, g/dscmb
(gr/dscf)
Average residual pressure drop (A P), cm w.g. (in. w.g.)
Initial residual A P, cm w.g. (in. w.g.)
Residual A P increase, cm w.g. (in. w.g.)
Filtration cycle time, s
Mass gain of test sample filter, g (gr)
Number of cleaning cycles
At Verification Test
Conditions
<0. 0000167°
(<0. 0000073)
<0. 0000167
(<0. 0000073)
2.72(1.07)
2.64(1.04)
0.21 (0.08)
180
0.08(1.29)
120
a Standard conditions: 101.3 kPa (14.7 psia) and 20 °C (68 °F). One or more of the impactor
substrate weight changes for these results were near the reproducibility of the balance.
b Total mass includes the mass of PM2 5 and larger particles that passed through the fabric.
meter. The detection limit is for a 6-hour test and based on VDI 3926.

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In accordance  with the  generic  verification protocol, this verification statement is  applicable to filter
media manufactured between the signature date of the verification statement and 3 years thereafter.
signed by Sally Gutierrez       5/7/2010                 signed by Jason Hill           4/5/2010
Sally Gutierrez                 Date                     Jason Hill                     Date
Director                                                Director
National Risk Management Research Laboratory          Air Pollution Control Technology Center
Office of Research and Development                     RTI International
United States Environmental Protection Agency
NOTICE: ETV verifications are based on an evaluation of technology performance under specific, predetermined
criteria and the appropriate quality assurance procedures.  EPA and RTI make no express or implied warranties as to
the performance of the technology and do not certify that a technology will always operate as verified. The end user
is solely responsible for complying with any and all applicable federal, state, and local requirements.  Mention of
commercial product names does not imply endorsement.

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