TEST NUMBER 73-ROC-l
INTERNATIONAL MINERALS
  AND CHEMICAL CORP.
  KINGSFORD, FLORIDA
         PEDCo ENVIRONMENTAL

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             PEDCo-EN VI RON MENTAL
                  SUITE 8 -  ATKINSON SQUARE
                       CINCINNATI. OHIO 45 3 4 G
                                 513 1-7-7 1-4330
 TEST NUMBER 73-ROC-l
INTERNATIONAL MINERALS
  AND CHEMICAL CORP.
  KINGSFORD, FLORIDA
    February, 1973
      Prepared By
Norman Kulujian, P.E.
Richard W. Gerstle, P.E.
 Contract No. 68-02-0237
      Task No. 12

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                    I.  TABLE OF CONTENTS

       Subject                                           Page

  II.  INTRODUCTION                                        1

 III.  SUMMARY OF RESULTS                                  3

  IV.  PROCESS DESCRIPTION        •                        10

   V.  PROCESS OPERATION                                  12

  VI.  LOCATION OF SAMPLING POINTS                        14

 VII.  SAMPLING AND ANALYTICAL PROCEDURES                 20

VIII.  APPENDIX                                           27

       A.  Complete Particulate Results with
           Example Calculations.

       B.  Complete Fluoride Results with
           Example .Calculations.

       C.  Process Operational Log.

       D.  Field Data.

       E.  Standard Sampling Procedures.

       F.  Laboratory Report.

       G.  Sample Number Log.

       H.  Test Log.

       I.  Sampling Handling Log.

       J.  Project Participants and Titles.

       K.  Presurvey Report.

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II. INTRODUCTION  .  •'   ' .."/.    " -'.;;; .    •;••'•••.'.

     Under the Clean Air Act of.  1970, as 'amended,  the Environ-

mental Protection Agency is 'charged with the establishment

of performance standards for stationary sources which may

contribute significantly to air  pollution.  A performance

standard is based on the best emission reduction  systems

which have been shown to be technically and economically

feasible.          .. .     ''.-.'             .  ,


     In order to set realistic performance standards, accurate

data on pollutant emissions must be gathered from  the stationary
                                                t  '
source category under consideration.


     Atmospheric emissions of particuJate and fluorides from

the International Minerals and Chemical Corporation  (IMC)

phosphorus plant dryer in Kingsford, Florida were  sampled to

establish a guide for New Source. Performance Standards as

authorized by the Clean Air Act  of 1970.  Triplicate tests were

made to determine particulate and fluoride concentrations at  the

inlet and outlet of the dryer scrubber.  The six  tests were made

February 12-15, 1973.                         ;'•.'


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     Wet phosphate rock enters the IMC dryer where the



particles are dried by hot furnace gases.  Dust entrainment



in the exit flue gases are scrubbed in a vertical spray



chamber scrubber.  Fluoride emissions in the phosphate rock



are driven off to the exit gases by the heat in the dryer.
                            - 2 -

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III. SUMMARY OF RESULTS



     Table 3.1 presents the overall test summary of particulate



and fluoride concentrations in U.S. and metric units.  Three
           i


particulate and three fluoride tests were averaged to obtain



values in Table 3.1.  Individual test results are shown as



follows in subsequent Tables:



Table                             Description



 3.2                      Particulate Analysis Summary



 3.3                      Fluoride Analysis Summary



 3.4                      Scrubber Water Analysis Summary



 3.5                      Rock Material Analysis Summary




     In all cases, except particulate Test 3, outlet flow



rates were slightly higher than volumes sampled at the inlet.



This may have been caused by a cyclonic flow distribution, but



since the maximum difference is only three percent, other



factors may have contributed to the variation.




     Individual particulate test data (Table 3.2) do not vary



appreciably for this type of process.  Outlet loadings from Run 1



are approximately twice the values from the last two runs, but



this could be due to the particle size distribution in the type



of feed.  Types of feed are discussed in Section V.




     The inlet combustion gas analysis for the particulate runs



indicates arise in 009 and a decrease in O  for the three tests.
                            - 3 -

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                                 Table 3.1  OVERALL SUMMARY OF RESULTS FROM PHOSPHATE ROCK DRYER
Pollutant
Measurement
System
Volume of Gas Sampled
Percent Moisture by Volume
Average Stack Temperature
Dry Stack Volumetric Flow Rate
Actual Stack Volumetric Flow Rate
Percent Isokinetic
Feed Rate
Partial Catcha
Weight
Concentration/Dry Volume
Concentration/Actual Volume
Concentration/Time
Lb/ton, Feed Concentration/
Input Feed Rate
Total Catch
Weight
Concentration/Dry Volume
Concentration/Actual Volume
Concentration/Time
Lb/ton. Feed Concentration/
Input Feed Rate
Percent Impinger Catch
Percent Insoluable Fluoride
Units
U.S.
DSCFb
%
op
DSCFM0
ACFMd
Ton/hr
mg
gr/DSCF
gr/ACF
Ib/hr
lb/tort

mg
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
%
'
Metric
DNm3
%
°C
M3/ g
'see
Mton/hr
mg
mg/DNm3
kg/hr
kg/Mton

mg
mg/m
kgAr
kg/Mton
%
•'
PARTICIPATE
U.S.
Inlet
51.608
31.63
164
65597
110262
107.6
333
5621
1.639
0.9783
923.8
2.741

5746
1.677
0.9922
945.5
2.810
2.55

Outlet
108.212
27.19
151
65040
101562
105.0
333
302
0.04275
0.02741
23.80
0.076

411
0.05832
0.03740
32.51
0.102
27.6

Metric
Inlet
1.4614
31.63
73.3
30.958
52.038
107.6
302
5621
3751
2239
419.0
1.371

5746
3837
226.2
428.9
1.405
2.55

Outlet
3.0642
27.19
66.1
30.696
47.932
105.0
302
302
97.83
62.72
10.80
0.0380

411
133.4
85.57
14.75
0.0510
27.6

FLUORIDE
U.S.
Inlet
65.795
31.89
164
65011
109554
107.8
295
3.8
0.00089
0.00053
0.50
0.0017

166.2
0.03902
0.02319
21.76
0.0732

97.7
Outlet
106.414
26.00
151
66754
102868
100.5
295
4.7
0.00068
0.00044
0.39
0.0014

27
0.0040
0.0026
2.3
0.0076

63
Metric
Inlet
1.8609
31.89
73.3
30.682
51.704
107.6
268
3.8
2.0
1.2
0.23
0.00085

166.2
89.28
53.06
9.870
0.0366

97.7
Outlet
3.0133
26.00
66.1
31.505
48.549
105.0
268
4.7
1.6
1.0
0.18
0.00070

27
9.2
5.9
1.0
0.0038

63
a)  For particulate, catch includes probe, cyclone and filter.  For fluoride, catch includes the water soluble  portion.
b)  Dry standard cubic feet at 70°F, 29.92 in. Hg.
c)  Dry standard cubic feet per minute at 70°F, 29.92 in. Hg.
d)  Actual cubic feet per minute
e)  Dry normal cubic meters at 21.1°C, 760 mm Hg.
f)  Dry normal cubic meters per second at 21.1°C, 760 mm Hg.
g)  Actual cubic meters per second

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                          Table 3.2  PARTICULATE EMISSION DATA SUMMARY
                       IMC Corp. , Kingsford, Florida - Rock Dryer Scrubber


Date
Volume of Gas Sampled-DSCFa
Percent Moisture by Volume
.Average Stack Temperature- °F
Inlet
1
2-12-73
43.182
31.06
164
Stack. Volumetric Flow Rate- 64,172
DSCFM
Stack Volumetric Flow Rate-
ACFMC
Percent Isckinetic
Percent CO2
Percent 0_
Percent CO

Feed Rate-ton/hr
Particulates-probe , cyclone ,
and filter catch
106,284

107.5
2.93
17.93
0.00

270


mg ' j 3170
gr/DSCF 1.133
gr/ACF 1 0.6840
i
Ib/hr j 623.2
Ib/ton feed

Particulates-total catch
mg

gr/DSCF

gr/ACF
Ib/hr
Ib/ton feed
Percent impinger catch
2.307
2
2-13-73
56.089
32.43
164
65,578

110,850

109.3
3.20
17.50
0.03

' 350


7566
2.082
1.231

1170
3.343
i

3315

1.185

0.7153
651.7
2.413
4.37

7698

2.118

1.253
1191
3.401
1.71
3
2-13-73
55.553
31.41
164
67,040

113,652

105.9
5.00 .
15.70
0.07

380


6128
1.702
1.020

978.2
2.574


6226

1.729

1.036
993.8
2.615
1.57
Outlet
1 j 2
2-12-73
111.796
26.94
151
64,707

100,604

108.9
5.00
15.43
0.03

270
*

438
0.06046
0.03892

33.53
0.124


537

0.07412

0.04772
41.11
0.152
18.4
2-13-73
10_6.232
27.15
150
66,569

103,573

100.6
3
2-13-73
106.817
27.48
152
63,843
I
100,508

105.5
4.03 5.47
15.13
0.00
15.57
0.03
i
350 380
i i
I

229
0.03326
0.02138

239
0.03452
0.02193

18.98
0.054


376

0 .05462
13.90
0.049


320

0.04623
i
0.03511 0.02936
31.12
0.089
39.1
25.30
0.066
25.3
i
a) Dry standard cubic feet at 70°F, 29.92 in. Kg.
b) Dry standard cubic feet per minute at 70°F, 29.92 in. Hg.
c) Actual cubic feet per minute.

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The Orsat apparatus did not have a water jacket around the




gas tube which may have varied the gas temperature and, in turn,



the gas analysis.






     The insoluble portion of the outlet fluoride catch (Run 5,



Table 3.3) is approximately an order of magnitude greater than



values from the other two tests.  Duplicate laboratory analysis



produced the same results.  A 60% pebble - 40% concentrate was



being fed to the dryer during this test.  The fluoride analysis



of the feed (Table 3.5) confirms the rock was similar to other



runs.  Therefore it appears that the scrubber efficiency was



lower during this run.






     After each of the three fluoride runs, 100 ml of inlet



and outlet sample was removed and given to IMC personnel for



their analysis.  This was considered when EPA analyzed the



samples for fluoride concentration.






     No major testing problems occurred during sampling at the



Kingsford site.  A pump in one of the outlet meter boxes acted



up at times, so another meter box was used to complete the tests,



A cyclone bypass connector on the outlet train broke after one



test was complete, so the sample stayed intact.  During the last



fluoride test, the probe contacted the mud on the inside of the



duct creating a vacuum in the sample train.  The impinger water
                             -  6  -

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                     Table 3.3   FLUORIDE  EMISSION DATA SUMMARY
                  IMC Corp.,  Kingsford, Florida - Rock Dryer Scrubber
'
Date
Volume of Gas Sampled-DSCFa
Percent Moisture by Volume
Average Stack. Temperature-°F
Stack Volumetric Flow Rate-
DSCFMb
Stack Volumetric Flow Rate-
ACFMC
Percent Isokinetic
Feed Rate-ton/hr
Fluoride-water soluble
mg
gr/DSCF
gr/ACF
Ib/hr
Ib/ton feed
Fluoride -total
mg
gr/DSCF
gr/ACF
Ib/hr
Ib/ton feed
Percent insoluble fluoride
Inlet
4
2-14-73
66.354
33.19
164
64,884
111,213
108.9
270
3.1
0.00072
0.00042
0.400
0.0015
137.2
0.03190
0.01861
17.75
0.0654
97.7
5
2-14-73
65.280
32.27
164
65,641
111,127
105.9
300
5.7
0.00134
0.00079
0.758
0.0025
189.6
0.04482
0.02647
25.22
0.083S
97.0
6
2-15-73
65.751
30.22
164
64,528
106,321
108.5
315
2.6
0.00061
0.00037
0.337
0.0011
171.9
0.04034
0.02448
22.30
0.0705
93.5
Outlet |
4
2-14-73
105.672
25.45
151
66,251
101,226
100.6
270
5.6
0.00082
0.00053
0.464
0.0017
7.9
0.00115
0.00075
0.655
0.0024
29.1
5
2-14-73
105.913
24.92
150
67,700
102,610
98.6
300
6.3
0.00091
0.00060
0.532
0.0018
67.4
0.00982
0.00648
5.69S
0.0187
90.7
6
2-15-73
107.658
27.64
151
66,312
104,767
102.4
315
2.2 :
i
0.00031
0.00019
0.179
0.0006
6.9
0.00098
0.00062
0.562
0.0018
68.1
a) Dry standard cubic feet at 70°F, 29.92 in. Hg.
b) Dry standard cubic feet per minute at 70°F, 29.92 in. Hg.
c)-Actual cubic feet per minute

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         Table 3.4.   SCRUBBER WATER ANALYSIS SUMMARY
Item
Total Fluorides, mg/1
P205, mg/1
PH
Test Number i
Scrubber Inlet
4
0.4
0.1
7.77
5
0.4
0.1
7.93
6
0.4
0.1
7.81
Avg.
0.4
0.1
7.84
Scrubber Outlet
4
1.3
1.4
7.60
5
1.2
1.2
7.89
6
1.1
1.4
7.66
Avg_.
1.2
1.3
7.72
         Table  3.5.   ROCK MATERIAL ANALYSIS  SUMMARY
Test
1
2
3
4
5
6
Total Fluoride, mg/gm
Raw Feed
38.9
37.8
38.5
38.6
36.9
38.5
Dry Product
36.2
39.9
39.2
38.5
37.1
39.4
Total P20sr %
Raw Feed
31.1
30.5
33.0
31.8
31.5
32.4
Dry Product
31.8
32.4
33.1
30.9
30.7
33.8
Sample collection times can be found in Appendix H.
                                - 8 -

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backed up and wet the filter.  The sampling team replaced the



filter without losing any of the sample water.
                            -  9  -

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IV.  PROCESS DESCRIPTION




     A phosphate rock plant flow diagram, shown in Figure 4.1,



illustrates the steps of the process in relation to the drying



operation.  After the phosphate rock is mined, a flotation



process separates the impurities by chemically separating the



impurities from the phosphate sand.  The washed rock is then



conveyed to storage bins.






     The wet rock contains between 7 and 20 percent moisture



while being transported to the drying site.  All grades of rock



are normally dried to 3 percent or less in the drying operation,






     The IMC.rock dryer at Kingsford, Florida is a 270 TPH



fluid bed unit.  The rock is dried by heat supplied by natural



gas, with No.  5 residual fuel oil as a standby.





     From the drier, combustion gases enter a cyclone



separator where the majority of the particulate is removed



and recycled back to the product conveyor belt.  The gases



then flow to a cyclonic scrubber using fresh water as the



scrubbing media.  The clean gas flow leaves the scrubber and



exits through a ninety foot stack.
                            - 10 -

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HIGH PRESSURE
       WATER
DRAGLINE
                 ~7  \  RECOVERY PLANT

                     CI
                                                             WASHER
                             >, r^x^     ^
                           -—-». • *  \ *•' V N/ V V
                          -XV \V    ' / V VX'N  NX
                         , ' /-- '< ^    A/V v v\X    M ! M r
                         (>^S7^^^    M'Nl-
                         '.x^xx x vyy v v \2i2iiX
PUMP
                                    777-
                                                      SURGE
                                                     HOPPER
                      DRY ROCK
                       STORAGE
                                             DRY ROCK
                                             SHIPPING

                 GROUND ROCK
               J SH PPING
                        WET
                        ROCK
                     SHIPPING
                                                                            WET ROCK STORAGE
                                                                              AND RECOVERY
                       Figure  4.1.  Phosphate rock  flow sheet.

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V.  PROCESS OPERATION*



     The operations at the Kingsford rock drying plant were



monitored from the systems control room by Mr. J. Peoples



of EPA.  From this vantage point, Mr. Peoples was able to



collect data and communicate any upsets or abnormalities



during the testing periods to the test crew.  Data recorded



included recording times, feed and production rates, and other



additional information related to the fluid bed dryer and



scrubber cleaning operation (Appendix C tabulates this informa-



tion along with related comments).






     Particulate and fluoride tests were conducted at the



rock drying plant during the week of February 12, 1973.  On



the first day, Feb. 12, 1973, no process or sampling problems



were encountered while conducting Run 1.  However, fuel oil



to furnish heat for the dryer was substituted for natural gas



due to the fuel shortage.






     The raw materials fed to the dryer consisted of a mixture



of 60% pebble - 40% concentrate.  For the second particulate



feed-in materials consisted of 70% pebble - 30% concentrate.



One process shutdown occurred during the second run and delayed



testing from 11:00 A.M. until 12:50 P.M. due to conveyor belt



trouble.  The dryer feed for the third run was 100% concentrate.
*Written and supplied by EPA.
                           - 12

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     On Wednesday, Feb. 14, at 9:10 A.M. the fluoride tests



were begun at Kingsford.  A mixture of 60% pebble - 40% concen-



trate was being processed during runs one (1) and two  (2).



Test three (3) was completed on Thursday with 100% concentrate



being processed under normal conditions.  No process upsets



interfered with these tests.






     The opacity of the Kingsford dryer effluent was difficult



to estimate because of the high moisture content.
                          - 13 -

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VI  LOCATION OF SAMPLING POINTS






A.  Inlet Location



     The configuration of the ductwork downstream of the drier



as shown in Figure 6.1 made it impossible to choose a section



completely free of turbulent effects.  The best possible



sampling location was chosen at a point nine inches upstream



from two vertical water sprays and approximately twelve feet



downstream of an induced draft fan.






     Since this chosen sampling location was less than 0.5 diameters



from the water sprays, the maximum number of traverse points



was chosen as required by the Federal Register, Vol. 36, No. 247.



Figure 1.1, Dimensions of the duct are 79 inches high by 56.5



inches wide.  Five ports were decided upon with ten traverse



points per port for a total of fifty  (50) points as illustrated



in Figure 6.2.  Each sampling area would then theoretically



be 15.8 inches long by 5.65 inches wide, resulting in an aspect



ratio of 2.66,  Increasing the sampling ports would reduce the



aspect ratio but the existing framework around the bypass



stack made this impossible, since a minimum of 14 inches was



needed from the existing framework to the sampling port.






     Actual sampling areas in Figure 6.2 are somewhat smaller



than theoretical areas due to a 6 to 7 inch layer of mud on



the bottom of the duct.  This reduction in area was considered in
                            - 14 -

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      Figure 6.1  Dryer Inlet Location
        Gas Flow
     cyclone
     scrubber
     and existing
     stack
24"  /  water sprays
    -
                      _ j
               Top View
            78" ID
   water spray line
sampling platform
                         A

                         B

                         C
                                  sampling
                                  port
                      Elevation
                          - 15 -

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            Figure 6.2  Inlet Traverse Points
  .-H 4"
 I
7.5"
           o-   o
14.5"
14"
14"
14"
15"
Al  A2   A3  A4   A5   A6  A7   A8  A9   A10
          Bl  B2   B3  B4   B5   B6  B7   B8  B9   BIO

           OOOOOOOSOO
          Cl  C2   C3  C4   C5   C6  C7  C8   C9   CIO
          Dl  D2   D3  D4   D5   D6  D7  D8   D9   D10
          El  E2   E3  E4   E5   E6  E7  E8   E9   E10

           OOOO    OGOOOO
                "6 to 7 inch mud layer
                                                          79"
                            56.5"
                  Looking Down Stream
                              - 16 -

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determining air flow rates.  A bypass stack without control



equipment is less than one duct diameter upstream from the



chosen sampling location and was blocked off by a damper



which eliminated air stream turbulence.






B.  Outlet Location



     The rock drying operation is equipped with a stack



approximately 90 feet high.  Two existing ports were found



to be satisfactory for emission testing.  A diagram of the



stack is shown in Figure 6.3 with sampling port and water



spray locations.  Two sampling locations, 90.degrees apart



are needed for vertical stack sampling  (Federal Register,



Vol. 36,,No. 247, Page 24882).  When dimensions of the stack



were taken, it was noticed the ports were only 80 to 85



degrees apart, which was assumed to be satisfactory.






     The stack is 83 inches in diameter at the sampling



location.  Ports are located 6 ft. below the top of the stack,



and 10 ft. above the closest obstruction.  Forty-eight sampling



points (24 along each diameter) were chosen to satisfy traverse



point requirements as specified by the Federal Register.  A cross



section of the stack is shown in Figure 6.4 with the chosen



sampling points.






     A portion of the existing railing had to be removed to



allow for the sample box traverse.  A support platform was



designed so the sample box could be overhung over the walk,



since the needed sampling width was much greater than the



catwalk width of 30 inches.





                           -  17 -

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Figure 6.3  Dryer Outlet Location
                         -83"ID-H
                       no:
   Outlet Ports
                        \

              T
             17'10"
                  •c
              11...
  Water Sprays
Water Manifold

                                       10'
                                       5'6'
                         Gas Flow
                                       51'9'
                                                 Inlet Duct
                                        78"
                             \
                                  Water Exit
                  Elevation
                      -  18  -

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Figure 6.4  Outlet Traverse Points
      Traverse Point Locations are Tabulated in Appendix D
                       — Port B
                     Looking Down
                          -  19 -

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VII.  SAMPLING PROCEDURES                          f




     All particulate and fluoride sampling procedures were



selected and approved by EPA prior to field sampling.  The



contractor performed all testing and sample recovery operations;



collected samples were analyzed by EPA personnel.  The inlet



and outlet sampling crew consisted of two man teams which



included a meter and probe technician.





     At the inlet site, there was a relatively high positive



pressure combined with high humidity air at approximately



165°F.  Water condensed in the first two impingers which had



to be replaced midway through the test.  After each inlet test



the total water volume was determined and properly stored for



analysis.






     The outlet meter box was positioned approximately fifty



feet below the sampling site.  Since the diameter of the



stack was much greater than the width of the catwalk, two



different probe lengths reduced the sample box overhang.






Preliminary Traverse and Moisture



     A preliminary velocity traverse at the inlet and outlet



location determined approximate nozzle sizes and isokinetic



sampling conditions.  A 0.180 inch I.D. nozzle was used for



subsequent inlet testing while the outlet was sampled with a



0.277 inch I.D. nozzle.
                           - 20 -

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     The inlet stack gas moisture was determined by a train



similar to Figure 4.2, Federal Register, Vol. 36, No. 247,



Page 24887,  Tests on inlet flue gas indicated values were close



to saturation; the outlet gas was assumed to be saturated.






Gas Velocity and Temperature



     Velocities were measured at each sampling point across the



stack diameter to determine an average value according to pro-



cedures described in the Federal Register.  Flow rates were



calculated from velocities at inlet and outlet stations from



which flow continuity was checked.  Gas flow temperatures were



measured by long stem dial thermometers.






Molecular Weight and Gas Analysis



     An integrated sample of the stack  gases was collected



at the inlet and outlet during each particulate run by pumping



flue gas into a Mylar bag at the rate of  approximately 0.5 liter



per minute.  This bag sample was then analyzed on-site with an



Orsat apparatus for CO?, 0_, and CO.  Prior to the first  test



all chemical reagents were  changed to assure accurate readings.



The molecular weights of the particulate  combustion gas ranged



from 29.19 to 29.50.  A molecular weight  of 29.00 was assumed



for all fluoride test calculations.
                           -  21 -

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Particulate Sampling



     Particulate matter was isokinetically sampled from the



drying operation with a train shown in Figure 7.1  Although



the Federal Register stipulates a minimum sampling time of 5



minutes for each sampling point, shorter times were used due



to the number of traverse points selected.






     The train consisted of a stainless steel nozzle, a heated



glass probe (a 6 ft. probe was used at the inlet while testing



at the outlet was done with 4 ft. and 8 ft. lengths), a heated



glass fiber filter, and four impingers connected in series



with glass ball joint fittings.  The first two impingers



contained 100 ml of water each, the third impinger was left



empty and approximately 200 grams of preweighed silica gel



were placed in the fourth impinger.






     In all cases sampling was conducted under isokinetic



conditions by continually monitoring the velocity with a pitot



tube and adjusting the sampling rate accordingly.









     At the inlet site, the first impinger initially containing



100 ml. of water had to be replaced midway during the tests



due to the large volume of water which condensed in the



impinger.  The stack team was very careful so as not to contact



the nozzle with the muddy ports and stack walls when changing



ports.
                           -  22 -

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                                                           FILTER HOLDER.
                                  STACK WALL
                                                                                           THERMOMETER
U)
I
                 REVERSE-TYPE
                 PITOT TUBE
                                                         DRY TEST METER       VACUUM PUMP
                                      Figure 7.1.   Particulate sampling  train,

-------
     The train cleanup procedure consisted of measuring the



water collected and weighing the silica gel to determine



moisture content.  The water was then poured into a glass



jar.  The filter was removed and placed in a marked container.



The probe and front half of the filter holder were then rinsed



with analytical reagent grade acetone and the washings placed in



a glass container.  The rear half of the train consisting of



filter holder, impingers, and connectors was  rinsed with



distilled water and this water added to the impinger contents.



The rear half of the train was then rinsed with acetone and



placed in a third sample jar.  A portion of the acetone and



distilled water used in the sample recovery were set aside and



used as blanks for analysis.






Fluoride Sampling



     Particulate and gaseous fluorides were withdrawn iso-



kinetically from the phosphate drying operation with the train



shown in Figure 7.2.





     The design and contents of the four impingers are identical



to  the particulate train.  An unheated filter holder containing



a Whatman No. 41 paper filter was placed between the third and



fourth impingers to trap particulate fluorides.  Contents of



the first three impingers, water wash of probe, nozzle, and



filter holder were placed in the same container.  No acetone



wash was required for the fluoride clean up.
                            - 24 -

-------
NJ

Ul
                  PROSE




                  fc=l
                    £
                   U.
              REVERSE-TYPE

              PITOT TU8E
                                STAC KW ALL
                                                                                     THtRMOMEfEP.
FILTER HOLDER
                           \
                                                  CRY TEST METER
                                                                   VAC'JU.'/ PU.UP
                                Figure  7.2   Fluoride  Sampling  Train

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     During the first fluoride test, the filter exhibited a




darkish brown color.  Since the Whatman filter was unheated,



the exhaust gas constituents must have accounted for the color



change.  As explained earlier in Section 3, the original pump



used at the outlet site sounded as if the vanes were sticking.



On the first outlet fluoride test, the flow rate was difficult



to maintain for isokinetic sampling (see Appendix D).  At high



velocities either the filter was starting to plug up or the



pump connections could have been loose.  In either case, another



pump was used for subsequent outlet testing.







     Scrubber water along with raw and finished product rock



samples were taken during each test.  Three scrubber water



samples during each test were measured for pH and temperature



and identified on the individual bottles.






Sample Storage



     All samples were placed in 1000 ml glass and polyethylene



containers and marked with EPA identification tags  (see



Appendix G).  The bottles were then put in wooden boxes with



styrofoam separators and hand delivered to EPA, North Carolina,



after all tests were completed.
                           - 26 -

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