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Table 3
Data Summary of Nomex Felt Post Run Analysis
Uncoated Coated
127 Hours 13 Hours 113 Hours
Inherent Viscosity 0.95 1.61 1.13
Amine End/106 g polymer 7.9 0.64 3.8
Frazier Air Permeability*
AP = 0.5" 51 42 52
Strip Tensiles X*
B.S., Ibs./in. 107 140 119
Grab Tensile. X*
B.S., Ibs.
Wt.. oz/yd.2*
Thickness, mils*
328
15.5
121
427
17.4
131
372
14.8
124
*Permeability, Strip and Grab Tensile, Weight, and Thickness are based
on ASTM tests D737, 01682-Modified, D1910 and D1777, respectively.
28
-------
provides a summary of the data obtained. Inherent viscosity and amine
end analysis gives an indication of chemical breakdown; i.e. the lower
the viscosity and the higher the number of amine ends, the greater
the fabric deterioration. The balance of the tests conducted provide
primarily an indication of overall mechanical property changes. Data
is given for three cases: lime coated with thirteen hours of exposure,
coated with one hundred and thirteen hours of exposure and uncoated
with one hundred and twenty seven hours of exposure. It is observed
that both the uncoated bags and the precoated bags with over one
hundred hours of exposure show significant deterioration. In addition,
while the data is very limited it does appear that the precoating did
slow down the degradation to some extent.
29
-------
ECONOMIC CONSIDERATIONS
A preliminary evaluation of the economic factors was executed.
Hardware installed costs were determined for a fabric filter dust
collector sized for 70,000 ACFM at 250° F. This was done for the
following fabric materials: Nomex felt, Teflon felt, Teflon woven
and Gore-Tex on Nomex backing. Installed costs were also determined
for a comparably sized electrostatic precipitator. All costs are
based on vendor quotes obtained in February, 1974. Annual operating
costs and annualized costs were then determined. Example calculations
for computing costs can be found in Appendix A-5.
The installed costs for a fabric filter dust collector employing
Nomex felt are provided in Figure 13. The assumptions here were
firstly that it would be necessary to insulate the house and hopper
and secondly that continuous lime coating of the bags is required.
The air-to-cloth ratios considered were 4.3, 6.3 and 7.5. Fabric
filter (baghouse) sizes versus air-to-cloth ratios are given in
Table 4. The corresponding installed costs were found to be $164,000,
$141,700 and $104,000 or on the basis of $ dollars per ACFM, they are
$2.34, $2.02 and $1.48. These estimates were based upon a bag price
of $15.50 each (vendor quote).
Similarly, installed costs were determined for the case of Teflon
felt, These figures are provided in Figure 14. As in the case of
Nomex, the air-to-cloth ratios considered were 4.3, 6.3 and 7.5. The
corresponding installed costs were found to be $187,200, $153,300 and
$115,800. On a $/ACFM basis these same costs were $2.67, $2.19 and
$1.65. Because of the quick release properties of the Teflon and also
its resistance to chemical attack it was assumed that no insulation
and no lime coating would be required. The price of the Teflon felt
bags was taken to be $50/bag (vendor quote) for the purpose of these
estimates.
30
-------
Figure 13
Installed Coat vs. Air-to-Cloth Ratio
150
o
O
to
o
o
o
0)
100
CASE: Nomex Felt, Reverse Air
Cleaning, Insulated
Lime Coated
a
c
50
8
10
11
Air-to-Cloth Ratio (ACFM/Ft. )
31
-------
Table 4
Fabric Filter Unit Size
vs.
Air-to-Cloth Ratio
-to-Cloth
Ratio
2.9*
4.3
6.3
7.5
8.7
12.5
Number
of Cells
54
28
20
16
14
10
Number
of Bags
2,916
1,512
1,080
864
756
540
Net Filter
Area - Sq. Ft
31,620
16,120
11,160
9,300
8,060
5,580
*Based on three (3) units: each with 18 cells, 972 bags and
10,540 ft. net filter area. One unit is always off stream
due to shaker operation.
32
-------
o
Q
CO
O
0}
o
u
(0
c
Figure 14
Installed Cost vs. Air-to-Cloth Ratio
150-
100
I
6 7 8 9 10
Air-to-Cloth Ratio
11 12
CASE: Teflon Felt, Reverse Air Cleaning
Uninsulated, No Coating
33
-------
Figure 15 provides the installed costs for the case of Gore-Tex
bags. Based upon the bench studies of this material it appears that
air-to-cloth ratios higher than those achievable on felt might be
possible. For this reason the annualized costs were investigated up
to an air-to-cloth ratio of 12.5/1. The ratios investigated were 4.3,
6.3, 7.5, 8.7 and 12.5. The corresponding annualized costs were
determined to be $138,816, $118,800, $88,152, $82,948 and $72,940. On
the dollar per ACFM basis these same figures are $1.98, $1.69, $1.25,
$1.18 and $1.04. As with Teflon it was assumed no insulation and no
coating would be required. The price of Gore-Tex is assumed to be $18
per bag (vendor quote). The inflection point in the curve of Figure
15 is due to the higher percentage of total cost attributed to the
house at the lower A/C ratios as opposed to a higher percentage of
total cost attributed to the bags at the higher A/C ratios.
A graphical comparison of the installed costs for these three bag
materials is made in Figure 16. Teflon felt is seen to be the most
expensive route for all three air-to-cloth ratios investigated and
Gore-Tex is seen to be the least expensive for the same air-to-cloth
ratios. The curves draw closer as the air-to-cloth ratio increases.
One case for a continuous shaker was studied. Woven Teflon bags
were chosen as the filter media and an air-to-cloth ratio of 2.9 was
assumed. For this case a low air-to-cloth ratio was used, simply for
economic comparison. If this case is competitive then all others
would be also. A bag price of $14.60 (vendor quote) was used. The
capital cost was found to be about $180,000.
The installed cost for an electrostatic precipitator capable of
handling 70,000 ACFM was determined for three levels of efficiency.
The bases for development of these costs are provided in Table 5
These were 98, 99 and 99.5% removal efficiency. The difference in
grain loading of 0.5 vs. 0.4 for Kerr boiler is not considered signif-
icant. The corresponding installed cost was determined to be $202,300,
34
-------
Figure 15
Installed Cost vs. Air-to-Cloth Ratio
CASE: Gore-Tex on Nomex Backing,
Reverse Air Cleaning,
Uninsulated, No Coating
150
o
Q
oo
o
s
M
100
7 8 9 10
Air-to-Cloth Ratio
11
12 13
35
-------
200 r-
CD
M
tO
O
0
(0
o
u
0)
d
150
Figure 16
Installed Cost vs. Air-to-Cloth Ratio
CASES FOR EA£H FABRIC SAME AS
STATED INDIVIDUALLY
Nomex Felt
Teflon Felt
Gore-Tex
100
5QJ
_L
6789
Air-to-Cloth Ratio
10
36
-------
Table 5
Electrostatic Precipitator Purchase Cost Basis
Design Efficiency: 98%
Inlet Conditions: %% S Coal, % Grain/ACFM Inlet Loading
Precipitator Design:
Type = Cold Precipitator
2
Collection Surface Requirement = 22,800 ft.
Plate Height = 30 ft.
No. of Ducts = 15
Treatment Length = 27 ft.
No. of Electrical Sections = 3 (9 ft. ea.)
No. of Power Supplies = 3 (500 milliamps each)
Assembled Flange-to-Flange Selling Price = $119,000
37
-------
$248,800 and $279,200. These are shown in Figure 17. On a $/ACFM
basis, these same costs are $2.89, $3.55 and $3.99. Thus the installed
cost of the electrostatic precipitator even at 98% efficiency is
greater than that of fabric filter dust collector even when Teflon felt
is employed at an air-to-cloth ratio of 4.3.
Operating costs were also determined. For the three bag materials
under study, operating costs versus air-to-cloth ratios are provided in
Figure 18. The worst case of $26,200 per year was Teflon felt at an
air-to-cloth ratio of 4.3; while the best base of $9,800 per year was
Gore-Tex at an air-to-cloth ratio of 12.5. The main assumptions were
25% bag replacement per year and a pressure drop of 5 inches of water.
Two curves for Teflon felt are given. The higher was for 25% bag
replacement per year and the lower for 20% bag replacement per year.
Finally, the annualized costs were developed from the preceeding
installed and operating costs. These results are shown in Figure 19
Here it is seen that at air-to-cloth ratios of 7.5 and greater all the
bag materials studied will have annualized cost below that of an
electrostatic precipitator operating at 98 percent efficiency.
One separate economic study conducted was aimed at evaluating the
costs of preheating the inlet gas stream to the baghouse in order to
determine if avoidance of dew point excursions via this route is
economically feasible. Avoidance of the acid dew point is assumed to
be a favorable factor in filter media life. Based upon the operating
costs for various heating alternatives shown in Table 6, natural gas
is the least expensive alternative. See example calculation for
computing direct heating fuel costs in Appendix A-5. The capital cost
for the natural gas system hardware is in the range of $2,000 to $3,000.
Thus in relation to the total control system capital outlay, the heating
system is a small figure; however, in terms of operating costs if a
temperature rise of fifty degrees is required the annual fuel costs are
still very high relative to an annual operating cost in the range of
38
-------
300
Figure 17
Installed Costs vs. Efficiency
Case: Electrostatic Precipitator
o
Q
250
4J
CO
o
o
0)
rH
rH
B)
4J
c
200
150
98.0
98.5 99.0
Efficiency %
99.5
100
39
-------
Figure 18
Annual Operating Costs
vs.
Air-to-Cloth Ratio
30;
CASE:
en
j-i
cd
o
o
on
o
o>
o
oo
C
Reverse Air Cleaning
25% Bag Replacement/Year
Power Costs - $.0175/KWH
Operating Time - 6240 Hrs./Yr.
AP - 5" H00
20
O
A
O
Q
Nomex
Teflon Felt
Gore-Tex
Teflon Felt at 20%
Bag Replacement/
Year
-------
Figure 19
Annualized Cost vs. Air-to-Cloth Ratio
ro
O
c
o
u
en
o
u
0)
N
CO
c
o
H
o
A
o
Q
o
Nomex
Teflon Felt
25% Bag Replacement
Gore-Tex
Teflon Felt
20% Bag Replacement
ESP at 98%
^-0-\s«- O
7 8 9 10 11
Air-to-Cloth (ACFM/Ft.9
14
-------
Table 6
Annual Fuel Cost
Direct Heating to Avoid Condensation
Heater Type Dollars/Year
Natural Gas 28,500
Fuel Oil 48,200
Propane 69,200
Electricity 84,100
Assumptions:
1. Operating Hours/Year = 6,240
2. Fuel Costs:
Natural Gas - $1.35/Thousand Cubic Feet
Fuel Oil - $30<£/Gallon
Propane - $30<£/Gallon
Electricity - $.017
-------
$10,000 to $14,000 as shown in Figure 18 for Nomex and Gore-Tex. It
appears that direct heating is not feasible unless the dust collection
system is insulated. Once insulated, it appears that the heater may
not be required.
43
-------
REFERENCES
1. Vandergrift, A. E., et al, "Particulate Pollutant System Study"
Volume I - Mass Emissions, May 1, 1971, P.B. 203 128, see p. 50.
2. Glockley, G. H., et. al, "Dust Collectors for Low Sulfur Fossil
Fuel Plants", ASME Air Pollution Control Division Proceedings
April 24-25, 1973, Philadelphia, Pennsylvania.
3. Bagwell, F. A., et al, "Design and Operating Experience With a
Filterhouse Installed On An Oil-Fired Boiler", Presented to Air
Pollution Control Association. St. Paul, Minnesota, June 1968.
4. Borgwardt, R. H., "Filtration Characteristics of Fly Ash From A
Pulverized Coal Fired Power Plant, JAPCA VI8 N6, p. 387, June
1968.
5. IGCI/AMBA Joint Technical Committee Survey for Stoker Boilers.
44
-------
Appendices
A-l Filter Material Specifications and 46
Gore-Tex Bench Results
A-2 K« Determinations 52
A-3 Annualized Cost and Direct Fired Heating 55
Cost - Sample Calculations
A-4 Kerr Coal Analysis and Steam Flow Charts 59
A-5 Stack Emission Test Report
45
-------
Appendix A-l
Filter Material Specification
and
Gore-Tex Bench Results
46
-------
Table A-l
Filter Media Characteristics
Filter
Media
Nomex Felt1
Teflon Felt2
Style 2663
Gore-Tex3
Weight
Ozs./Yd/
14
24-26
4-5 +
Laminate
Permeability
CFM/Sq. Ft.
25-35
15-35
8-15
Mullen
Burst
psi
450
250
329-400
Weave
Design
Twi 1 1
Teflon Woven2 8
Style 954
Dralon T Felt4 13-15
20-40
20-30
250
3X1
1 - High Temperature Resistant Nylon Fiber (Polyamide)
2 - Tectrafluoroethylene (TFC) Fluro-Carbon
3 - Expanded Teflon (Polytetrafluroethylene) with Interlacing Air
Filled Pores
4 - Homopolymer of 100% Acrylonitrile
47
-------
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Test Parameters
Air-to-Cloth Ratio: 14:1
Air Flow Rate: 25 cfm
Temperature: Ambient
Pulse Rate: 1 Pulse/Minute
Air Pressure of Pulse: 70 psi _
Solids Feed Rate: 5 grains/ft.
Test Dust: Funkhauser Limestone
Data not taken on Kerr Pilot Unit
KEY:
15r-
o
o
O
n
A
Felted Nomex
Felted Nomex
(A)
(B)
Felted Polyester
Gore-Tex/Nomex
Gore-Tex/PTFE (G-T)
O
_Gore-Tex/
a n--
Gore-Tex/PTFE
To-
Nomex
T)
10 20 30 40 50
Running Time, Hours
60
70
Figure A-2
Performance of Gore-Tex Filter Bags
Pressure Drop vs. Time
(Results Provided by W. L. Gore & Associates, Elkton, Md.)
51
-------
Appendix A-2
K' Determinations
52
-------
Appendix A-2
1C Determinations
A few determinations of the "Specific Cake Resistance" K£ for both
Gore-Tex and Nomex.
Data of 9/19/73 allowed for the following Nomex felt case calculation:
K- - (0.60) (620)2 (7000)
^2 ~ 7810 (10) (0.8) (195) (15.43)
K = 8.6
Data of 8/30/73 allowed for the following Nomex felt case:
_ (1.4) (620)2 (7000)
5000 (3) (0.8) (250MT5.43)
K£ = 81
Data of 8/30/74 allowed for the following Gore-Tex/Nomex case:
1.2) (620)2 (7000)
^
(0-
K2 5000 (2) (0.8) (250) (15.43)
= 104
N.B. The value chosen for the 'gas volume is based upon the assumption
of equal distribution of the gas.
The above calculations were based on the following formula:
- - ( PT- PE) (A)2 (7000 grains/lb)
"
E) (A)
-FJ (R
_
2 (Q) (T) (1-FJ (R) (15.43 grains/gram)
Where: APr ~ Final pressure drop across collected dust and
filter cloth, in W.C.
Apr - Initial pressure drop across clean cloth, in
h W.C.
- 53 -
-------
Formula (continued)
o
A = Bag area (total filtration area), ft.
T = Filtration time from start of filtration to
clean down, min.
F = Fallout fraction, dust that never gets on
fabric, but goes to hopper.
R = Average dust feed rate to baghouse, grams/min.
Q = Gas glow rate, ACFM
54
-------
Appendix A-3
Annualized Cost and Direct Fired Heating
Cost - Sample Calculations
55
-------
Annual i zed Cost - Example Calculation
Formula for figuring theoretical annual cost (s) for operation and
maintenance from Edminsten, N.G. and Bunyard, F. L., "A Systematic
Procedure For Determining The Cost Of Controlling Particulate Emissions
From Industrial Sources", JAPCA V20 N7, p. 446, July 1970.
G = S PHK + W
Where:
S = Design Capacity of Fabric Filter in ACFM
P = Pressure Drop, Inches of Water
E = Fan Efficiency
0.7457 = A Constant (1 hp = 0.7457 KW)
H = Annual Operating Time in Hours
K = Power Cost, Dollars Per Kilowatt-Hour
M = Maintenance Cost, Dollars Per ACFM
In this case:
S = 70,000 ACFM
P = 5 Inches of Water
E = 60%
H = 6,240 Hours
K = $.0175/KWH
M = [No. of Bags in House X 25% Replacement Rate X Cost
Per Bag] IS
M = 1Q80 Bags X .25 X $15.50/Bag = $.06/ACFM
70,000 ACFM
Assuming a 60% fan efficiency reduces the above equation for
G to
G = S [195.5 X 10"6 PHK + M]
56
-------
Substituting the figures above yields
G = 70,000 [195.5 X 10"6 X 5 X 6,240 X .0175 + .06]
= 70,000 [.106 + .06]
= 70,000 [.166]
= $11,620
Formula for figuring annualized capital cost is equal to depreci-
ation plus capital charges.
Depreciation is assumed to be 6 2/3% of investment cost. The
capital charges are assumed to be equal to the depreciation, therefore
the annualized capital cost = .133 X total investment cost .
Total investment = $141,660 from annualized capital =
.133 X $141,600
= $18,841
For the example we are working with the total annualized cost of
control equals annual operating cost plus the annualized capital cost.
Total annualized cost equals $18,841 + $11,620 = $30,461
57
-------
Direct Heating Fuel Cost - Example Calculation
1. BTU/Hr. = (SCFM Air) (1.1) (AT°F)
70,000 X = 70,000 X = 49,200 SCFM
BTU/Hr. = (49,200) (1.1) (50)
= 2.706 X 106 BTU/Hr.
2.706 X 106 BTU/Hr. X 6,240 Hr. = 1.69 X 1010 BTU
2. Fuel oil is rated at 140,000 BTU/Gal. At .75% efficiency oil
puts out 105,000 BTU/Gal. Oil costs $.30/Gal.
2.706 X IP6 BTU/Hr. _ 25 -,-, G ^
.105 X 10° BTU/Gal. ' ' '
25.77 Gal.Hr. X $.30/Gal. X 6,240 Hrs. = $48,200
58
-------
Appendix A-4
Kerr Coal Analysis
and
Steam Flow Charts
59
-------
GENERAL TESTING & ENGINEERING COMPANY
Whitewood, Virginia
COMPANY: Jno. McCall Coal Company, Inc.
ADDRESS: Bluefield, West Virginia
MINE NAME: Loftis #2
LOCATION: Sharondale, Kentucky
SEAM: Cedar Grove
SIZE OF COAL: 1-1/4 X 1/4"
IDENTIFICATION: N&W 20376
DATE SAMPLED: 12/20/72
SAMPLED BY: G. Scott
SAMPLE RECEIVED: 12/21/72
SAMPLE SUBMITTED: 12/22/72
CERTIFICATE OF ANALYSIS
Laboratory Number
% Moisture
% Volatile Matter
% Fixed Carbon
% Ash
Total
% Sulphur
BTU
As Received
4.00
35.00
54.85
6.15
100.00
.60
13,850
Dry
36.45
57.14
6.41
100.00
.62
14,427
Fusion Temperature of Ash 2800 Plus
Free Swelling Index
Hardgrove Grindability Index
60
-------
xT
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--__ _.-- ^- ^ ^
-------
\
-------
Appendix A-5
Stack Emission Test Report
63
-------
INTRODUCTION
This report was prepared for the purpose of presenting the
results of emission tests conducted on January 23 and 24, 1973 a"t
Kerr Industries, Inc., Concord, North Carolina. -The tests were per-
formed on one of two coal-fired boilers and were conducted by
Michael Y. Aldridge of the North Carolina Office of Water and Air
Resources, Air Quality Division, and R. W. Buck of L. E. Wooten and
Company.
64
-------
CONTENTS
Introduction
Description of Boiler
Sampling and Analytical Procedure
Presentation and Discussion of Results
Calculation Procedures
Analytical Data and Test Data
Stack Gas Analysis
Field Data
Steam Plow Charts
Page 1
Page 2
Page 2
Page 3
Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
65
-------
A BRIEF DESCRIPTION OP
BOILER ON WHICH TESTS WERE PERFORMED
The steam generating facilities at Kerr Industries consist of
two Babcock and Wilcox boilers which are equipped with "Detroit
Rotostoker" spreader stokers. These boilers have a design capacity
of sixty thousand pounds of steam per hour, each with a two-hour
peaking capacity of seventy thousand pounds per hour. The design
efficiency of these units is 82 percent. Based on the above
parameters, the heat input for these units is 73.2 million BTU/hr
each. Both boilers are equipped with fans for supplying draft and
unit number two has overfire steam injection for better combustion
control.
SAMPLING AND ANALYTICAL
PROCEDURES
Equipment
The sampling train used for the tests described herein was the
E. P. A. type participate train described in the Federal Register
dated December 2j5, 1971, Volume 36, Number 2^7, Part II.
Sampling Schedule
Boiler number two was selected for testing and Kerr Industries
assumed the responsibility of installing ports in the stack. The
ports were situated 90° apart from each other. The equipment set
up was completed on January 22. One two-hour run was made on each
of the following days; each run consisted of spending ten minutes
at each of twelve sampling points. The filter holder was not large'
enough to handle the encountered concentrations, making it necessary
to stop periodically during testing to change filters. Run //I re-
quired the use of four filters; run $2 required the use of three
filters. Each filter was placed in a separate, labeled container.
66
-------
Sample Clean Up
At the end of each test run, the volumes of water condensed in
the impingers were measured to the nearest 1.0 ml. The silica gel
from the fourth irapinger was transferred to a collecting jar and
sealed. The last filter was carefully removed from its holder and
placed in a container and sealed. The probe, cyclone, and the
inlet side of the filter holder were washed with acetone. The
washings were captured in a collecting jar and sealed.
Analysis
The probe and cyclone washings were transferred to pre-woighed
beakers and placed in an oven at 90° C. The acetone was evaporated,
after which, the beakers were removed from the oven and allowed
to assume room temperature. The beakers, with the residues they
contained, were then weighed on an analytical balance to the near-
est 0.1 milligram. The tare weights of the beakers were subtracted
to determine the weight of the particulate residue. The filters
were similarly weighed and their tare weights subtracted. The
total particulate weight for a given run was considered to be the
sum of the beaker residues from the washings and the weight
differential of the filter.
The silica gel was weighed to the nearest 0.1 gram. The dry
weight of the silica gel vias subtracted to obtain the weight of
water captured. This quantity, expressed on a volume basis, was
added to the volume of water condensed in the first three impingers.
This sum was considered to be the total volume of water captured.
PRESENTATION AND
DISCUSSION OP RESULTS
The results of the first run indicate a particulate emission
rate of 131.4 Ib/hr. The results of the second run indicate an
emission rate of 135-6 Ib/hr.
The particulate regulation vzhich relates to emissions from coal-
fired boilers is stated as follows:
67
-------
"No person shall cause, suffer, allow or permit particulate
matter caused by the combustion of a fuel to be discharge from
any stack or chimney into the atmosphere in excess of the hourly
rate set forth in the following table:
Heat Input in Maximum Allowable Bniasion
Million BTU/hr of Particulate Matter in
Lbs/million BTU
Up to and including 10 0.60
100 0.33
1000 0.18
10,000 0.10"
In order to determine the allowable emission rate, the heat
input capacity of the unit must be determined. This determination
is made on the basis of design parameter as follows:
Design Steam Rate 60^000 Ib/hr
Design Efficiency 82$
BTU Input 73-2 million BTU/hr (Based on
1000 BTU/lb. steam)
A graph in the back of the "North Carolina Rules and Regulations
Governing the Control of Air Pollution" and referred to therein as
Figure 1 gives emission rates for all heat input. This graph eliminates
the need for interpolating the table which accompanies the regulation.
The emission factor (corresponding to a 73-2 million BTU/hr. input'
taken from this graph is 0.56 Ib/million BTU.
The application of this emission factor is based on the actual
operation conditions which existed during the test runs. These con-
ditions are as follows:
Run #1 Run #2
Actual Steam Rate, 1000 Ib/hr
(average from disk chart) 53-7 59.5
Operating Efficiency
(supplied by Kerr Industries) 11% 11%
BTU Input (million BTU) 69.7 77.3
(Based on 1000 BTU/lb. steam)
68
-------
Maximum Allowable Emission Run ^1 :
-------
PsM
Appendix A
CALCULATION PROCEDURES
The following are the formulae used in calculating the results
for each test run.
1. Stack Velocity:
V = K C - ... A
8 P Pi/ s V Ap
Where:
V = Average stack velocity, ft/sec
3
K = Units conversion factor = 85.48
P
C = Pi tot tube coefficient = .85
T = Stack temperature, °R
P = Absolute stack pressure, in. Hg
9
M = Molecular wt. of gas, Ib./lb. mole
Ap = Velocity pressure, in. HpO
2. Stack Volume Flow Rate;
Q = 60 v A
s s
Where:
Q. = Stack volume flow rate, ft. /min.
v = Stack velocity, ft./sec«
3 2
A = Cross sectional area of stack, ft.
Sample volume corrected to stack conditions;
V V T Pm
m = m . s n_
3 T P
m s
Where:
V = Sample volume corrected to staox conditions,
s
70
-------
V "3
ra = Sample volume as measured by dry gas meter, ft.
T
s = Absolute stack temperature, °R
T = Average absolute temperature of dry gas meter, °R
p
m = Absolute pressure of dry gas meter, in.Hg
p
s =: Absolute pressure in stack in. Eg
Volume of water vapor collected, corrected to stack conditions:
T
= .00267 VLq
s
'Where :
V "5
v = Vapor volume , f t .
V
Lq = Liquid volume, ml.
T
a = Absolute stack temperature, °R
P
s = Absolute stack pressure, in. Hg
5. Total sample volume at stack conditiona;
V V V
sample = m * v
s
"Where:
sample = Total wet volume of gas drawn into sampling train, ft.
Vm 3
s = Dry sample volume, ft.
V = Vapor volume, ft.
. 71
-------
6. Pollutant mass rate based on oarticulate concentration:
PMR0 = (0.1323) Wt Q
sample
VJhere:
PMR = Pollutant mass rate (concentration method), Ib./hr.
c
\J = Total weight of particulate matter collected for a
given run, gm.
Q = Stack volume flow rate, ft. /min.
V n = Total sample volume, ft.
sample
7« Pollutant mass rate calculated on the basis of the ratio of the
cross sectional areas of the stack and the sampling nozzle;
PMR «= (0.1323) W. Ac
Si U £
6 An
"Where:
PMR = Pollutant mass (ratio of areas method) IJb./hr.
d
₯ = Total weight of particulate matter collected for a
given run, gm.
2
A = Cross sectional area of stack, in.
Q
9 = Duration of test run, min.
2
A = Cross sectional area of sampling nozzle, in.
8. Percent isokineticity, % I;
%~L = (100) PMR
PMR
c
9« Average pollutant mass rate, PMR :
* ave
PMR = PIffi + PI'S
ave a c
-------
Appendix B
ANALYTICAL DATA AND TEST DATA
73
-------
ANALYTICAL DATA
Hun # 1 2
Filter weight differential, gm. 0.^709 0.^009
Residue from probe washings, gm. 3.11j59 3.2600
Total particulate weight, gm. jJ-58^8 3-6609
Impinger -water, volume differential,ml. 89 97
Silica gel weight differential, gm. 12.7 1^.5
Total water volume, ml. 101.7 111.5
74
-------
Appendix C
STACK GAS ANALYSIS
An. Orsat analysis was made on the stack gas in order to
determin its molecular weight.
The results are as follows:
Constituent Qy., ml.
CO,
CO
9.5
10.0
0.0
80.5
x 10"2 x
x 10~ x
_2
x 10 x
x 10~2 x
10
-2
Molecular
Weight
44
J52
28
28
Average Molecular Weight =
= 4.18
= 3.20
0.00
= 22.54
29.92 Ib/Lb mole.
75
-------
TEST DATA
Refer to Appendix A for Nomenclature
Run # 1 2
V , ft. /sec. 49.16 48.28
3
Q, c. f. m.
V , ft.5
m
V , ft.5
m *
1U
s
P , in. Hg
m
P , in. Hg
£>
V , ft.5
v1
V .. , ft.5
sample
PMR , Ib./hr.
C
PMR , Ib./hr.
Si
fa
35,925
87.6
132.5
29.30
29.25
7-59
140.1
121.6
141.2
116.1
35,285
82.3
126.1
29.40
29.35
8.26
134.4
127.2
144.2
113.4
76
-------
Appendix D
FIELD DATA
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORTNO.,
5EPA-650/2-74-058
3. RECIPIENT'S ACCESSION-NO.
|4. TITLE AND SUBTITLE
JApplying Fabric Filtration to Coal Fired Industrial
] Boilers (A Preliminary Pilot Scale Investigation)
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
Uohn D. McKenna
9. PERFORMING ORG \NIZATION NAME AND ADDRESS
Enviro-Systems and Research, Inc.
P. O. Box 658
Roanoke, Virginia 24004
10. PROGRAM ELEMENT NO.
1AB012; ROAP 21ADJ-038
11. CONTRACT/GRANT NO.
68-02-1093
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development, NERC-RTP
Control Systems Laboratory, Research Triangle
Park, NC; Enviro-Systems and Research, Inc.; and
Kfirr Indus trips Connnrd Nf!
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTE'S
is. ABSTRACT Tne report gives results of a preliminary pilot-scale investigation to deter-
mine the techno-economic feasibility of applying a fabric filter dust collector to coal-
fired industrial boilers. The pilot facility, on a slipstream of a 60,000 Ib/hr boiler,
was capable of handling 11,000 acfm at an air-to-cloth ratio (A/C) of 6/1. Filter medi;
evaluated include Nomex felt, Teflon woven, Teflon felt, and Gore-Tex laminate.
Overall efficiencies greater than 99. 5% were achieved with Nomex felt at an A/C of
6/1. Cleaning of Nomex felt bags improved with increasing volumes of reverse air.
The Nomex felt bags deteriorated. Both woven Teflon and Gore-Tex on Nomex back-
ing had better release properties than Nomex felt. Installed costs for a fabric filter
capable of handling 70,000 acfm and using Nomex felt at A/C of 4. 3, 6. 3, and 7. 5
were $164,000, #141,700, and $104,000 (3/acfm costs are $2.34, $2.02, and $1.48).
Installed costs for other filter media as well as electrostatic precipitation (ESP) at
three levels of efficiency are presented. Operating and annualized costs were also
determined and compared to those for an ESP. Based on 25% bag replacement per
year and an ESP efficiency level of 98%, Nomex felt and Gore-Tex on Nomex backing
are competitive with ESP at A/C greater than 4/1. A/C must be greater than 7/1
before Teflon felt becomes competitive. Another report is planned.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Air Pollution
Filtration
Filter Materials
Coal
Combustion
Industrial Heating
Boilers
Dust Collectors
Feasibility
Tetrafluoroethylene
Resins
re-Tex
13B
07D
13K , 14A
2 ID
2 IB , 111
13A
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
89
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
82
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