ATMOSPHERIC
EMISSION
EVALUATION
U.S. LIME
HENDERSON, NEVADA
TEST NO. 74 - LIM -4
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF AIR QUALITY PLANNING & STANDARDS
CONTRACT NO. 68-O2-O236
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U.S. LIME
HENDERSON, NEVADA
TABLE OF CONTENTS
I. Discussion of Results
«
II. Procedure
III. Clean-Up and Analysis
IV. Process Description and Operation
V. Computer Print-Outs °f Emission Data
VI. Appendix - Field Data Sheets
PAGE
1-6
7 - 8
9 - 10
11 - 12
13 - 20
21 - 43
(SECTIONS V AND VI ARE-NOT INCLUDED IN THIS REPORT)
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VALENTINE, FISHER & TDMLINSDN
CONSULTING ENGINEERS
«.».M,N.A.C.,A.A.A.»., B.A..M.H., I.B.C.
BZO LLOYD BUILDING or (zoe) 8ZS-C717
SEATTLE, WASHINGTON 98101
WM. M. VALENTINE, M.E.
ARTHUR K. FISHER, M.E.
GEORGE D. TOMLINSON, E.E.
BR. ASSOCIATES
WAYNE A. HANSON, M.E.
DOUGLAS W. PASCOE, E.E.
P. "CHIC" CICCHETTI
December 26, 1974
ASSOCIATES!
PHILIP W. WOODRUPF
DENNIS W. FINLAYSON
HENRY L. ROYCE, ILLUM.
WILLIAM T. MCDONALD
DEAN A. MANNIG
ROGER C. HUNTLEY
WESLEY D. SNOWDEN, P.E.
INDRU J. PRIMLANI. M.E.
PURPOSE
Emissions samples were taken on the outlet duct at a lime hydrator located at
Henderson, Nevada. The plant is owned and operated by U.S. Lime which is a
division of Flintkote Co. The plant used a baghouse for particulate reduction
purposes and was assumed to be one of the best controlled sources, in
connection with this type of industrial process. Results of the tests are
to be used by the EPA for evaluating and setting Nation-wide standards for
this type of industrial process.
SUMMARY
The evaluation was performed on April 23/24, 19/4. The outlet grain loadings
for the four samples were 0.0126, 0.0209, 0.0161, and 0.0186 for the
respective runs. The grain loading was not corrected for COo. The average
percent moisture for the four runs was 82.24%. The percent isokinetic
for the four respective runs was 153%, 194%, 155%, and 140%.
The standard cubic foot is defined at 70°F., 1 atmosphere pressure and dry.
VALENTINE, FISHER & TOMLINSON
Wesley D-xSttowden, P.E.
Manager^JEnvironmental Services
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DISCUSSION OF RESULTS
The sampling team arrived on the afternoon of April 22, 1974. Due to
U.S. Lime's early shutdown time of 4 P.M., work was not started until the
morning of April 23, 1974. The sampling equipment was setup according to
EPA Method 5 Procedures and a wet and dry bulb temperature was taken.
The approximate moisture content of the stack gases was determined by using a
high temperature psychrometric chart. This moisture content was 80%.
A nomograph was then set up using the collected data. The standard EPA
nomograph for isokinetic sampling is based upon a maximum moisture content
of 50%. This made it necessary to interpolate several values in order to
arrive at an approximate "K" value on the nomograph. A short 25-minute sample
was taken to confirm the moisture content and isokinetic sampling rate.
The moisture content agreed with the psychrometeric chart, but preliminary
calculations showed the precent isokinetic well below 100%. This was
attributed to the high moisture content of the stack gases. During the next
4 runs the air flow rate through the dry gas meter was hand calculated for
each point. At the completion of each test the isokinetic sampling rate
was calculated and adjustments were made. A review of the data summary shows
that the ideal 100% _+ 10% isokinetic sampling rate was not reached.
The isokinetic sampling rates for all of the five runs were substantially above
100%. This discrepancy can be accounted for by considering two factors.
The nomograph used was intended for moisture contents from 0% to 50%. This
made it necessary to interpolate several values in order to arrive at an
approximate "K" value on the nomograph, as mentioned above.
The second reason can be reviewed on the following graph. Curve No. 1 is
comparing the percent moisture and the percent isokineLic lor Lhe first lest
at U.S. Lime. For this run the "C" value was only approximated and the sample
was run to determine isokinetic values and percent moisture. As can be seen
the slope of the curve is quite steep in the area between 90% and 110%
isokinetic which are the allowable limits of EPA Method 5. If the original
determination of the percent moisture of the stack gases is in excess of +_ 3% •
of the actual, the percent isokinetic will be beyond the allowable limits. This
compares with a tolerance of + 11% moisture for stack gases in the vicinity
of 5% moisture content (Curve No. 2) which is a more typical percent moisture.
To demonstrate how the high moisture content could have affected over isokinetic
Values, the following conditions could apply. If the same nomograph setting
was used on Run No. 2 as on Run No. 1 the percent isokinetic for Run No. 2
would have been approximately 98% based upon the moisture correction. If
the same nomograph setting was used on Run No. 3 the percent isokinetic
would have been approximately 160% isokinetic. The conclusion is that when
sampling stack gases with this high of moisture content continuous
monitoring of the percent moisture with a wet bulb, dry bulb and psychrometric
chart is necessary and the nomograph or equations should be readily available
to make adjustments in the sampling flow rate.
The existing outlet duct was modified with a duct extension, (Figure 3)_ and
sampling was accomplished with this extension. A total of twelve (12)
sampling points were selected, three (3) traverses with 4 points each,
in the square stack. Data readings were taken every two and one-half
minutes with 5 minutes per point for a total of one hour per sample.
Due to the extremely high moisture content of the flue gases the impinger
section of the sampling train would become completely filled with condensed
water in approximately 30 minutes.
ffSr
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DISCUSSION OF RESULTS
PAGE TWO .
When this occured the sampling train was stopped and the backhalf of the sampling
train (impingers) was completely removed and a new section installed. Approximately
25 pounds of ice were required for each one hour run, due to the high heat content
of the nearly saturated gases.
COo readings were taken during each run with a Fyrite. The maximum value
which could accurately be read was 20% C0_. Any value greater than this had
to be read by visually extending the scale and interpolating the values. Due
to the extremely high moisture content a correction was made for the moisture
added to the fryrite solution, which could result in higher readings. The
Fyrite was zeroed and a C0~ reading was taken. After reading the C02
concentration, the Fyrite solution was released and allowed to return to its
neutral level. The difference between the original zero and this final neutral
level was deducted from the CO 2 reading and was assumed to be the fraction
added by the water vapor. This correction quantity never exceeded 1% (X>2
and in most cases was zero.
The outlet grain loadings were 0.0126, 0.0209, 0.0161 and 0.0186 grains per
standard cubic foot for Runs 2 through 5. Run No. 2 has a substantially
lower grain loading >than the other three runs. This can be accounted for
because of two factors. . Approximately 660 ml of sample was lost, thus only
1610 ml of the original 2270 ml was analyzed. An approximate value for the
particulate lost was calculated by determining the concentration of the
particulate in the remaining solution and multiplying it times the quantity
of solution lost. This can be considered only an approximation, as a review
of ths iiiipiriSvsr "CiGhcc of the othsr runs indic-itcc thct the "articulate vcs
not evenly distributed throughout the various sample bottles. The second
point is that no acetone wash of the impingers and bubblers was performed
•on this run.
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EFFE.CT Or MOISTURE! CONTENT OF STACK 6AS
ON /SO/C-//VE77C TOL.ERA/VCC
/SO-
yields 3i~/
'if
I
I
.©
„•*,,.«>.,
lo
lo
•KV-v1"
±31,
/VIOIS.
-i L- J
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DATA SUMMARY
LIME HYDRATOR - U.S. LIME
. HENDERSON, NEVADA
RUN
NO.
1**
2
3
4
5
AIR
ACFM
5367
6175
5791
5378
5895
FLOW
SCFM
683
939
581
675
539
PERCENT
MOISTURE
80.4
76.2
86.4'
80.7
85.7
PERCENT
ISOKINETIC
114
153
194
155
140
OUTLET GRAIN
LOADING (FRONT
HALF)*GR/SCF
-
0.0126
0.0209
0.0161
0.0186
PMR
(FRONT
HALF)*
LB/HR
-
0.102
0.104
0.093
0.086
Data based on particulate collected in front half of sampling train, uncorrected for non-isokinetic
conditions. Calculated using ratio of front half particulate to Pt of data print-out.
Sample collected to determine % moisture. Particulate collected was not analyzed.
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^4
^e-
k.
SIDE/ELEV. FRONT ELEV.
PLAN
SAMPLING PORT
PROVISIONS
HYDRATED LIME FACILITY
U S L IME CO.
ES-1
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PROCEDURE
(PARTICULATE SAMPLING TRAIN)
Stack gas sampling equipment designed by the United States Environmental
Protection Agency (EPA), Office of Air Programs was used on this evaluation.
A schematic of the sampling equipment is included in this report.
Sampling was performed according to the following:
Sampling ports were selected and installed. The number of sampling points were
determined considering the number of duct diameters between obstructions in the
duct up stream and down stream of the sampling ports. Stack pressure, temperature
moisture content and maximum velocity head readings were measured. An EPA
designed nomograph was set up using this data and the correct nozzle diameter
was selected using the nomograph.
The sampling train was prepared as follows:
An impinger was filled with approximately 500 gram of silica gel and weighed
to the nearest 0.1 gram. A filter (MSA 1106-BH) was labeled and dessicated
for at least 24 hours and weighed to the nearest 0.5 mg. 100 milligrams of
water was placed in the first and second impingers. The third impinger was
left dry. All three impingers were then weighed individually to the nearest
0.1 gram and recorded. •
A leak test.was preformed on the assembled sampling train. The leak rate
did not exceed O.Q2- cfm at a vacuum of 24 inches Hg. The probe was heated
so tliau the gas i_euip£i'aLui.*t at the probe cutlc-t was approximately 250 F. The
filter was heated to approximately 250°F. to avoid condensation of moisture
on the filter. Crushed ice was placed around the impingers at the beginning
of the test with new ice being added as.required to keep the gases leaving
the satapling train below 70°F.
The train was operated as follows:
The Probe was inserted into the stack to the first traverse point with the
nozzle tip pointing directly into the gas stream. The pump was started and
immediately adjusted to sample at isokinetic velocities. Equal time was spent .
at selected points of equal elemental areas of the duct with the pertinent
data being recorded from each time interval. The EPA nomograph was used to
maintain isokinetic sampling throughout the sampling period. At the conclusion
of the run the pump was turned off, the probe was removed, and the final
readings were recorded.
Clean up of the sample train and analysis of the samples was performed according
to the enclosed clean up and analysis procedure.
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PROCEDURE (continued)
The weight of the dust per volume and weight of dust per time were calculated
as follows:
The Concentration Method:
The condentration of dust entering the sampling nozzle is calculated and
then multiplied by the volumetric flow rate of the stack gases to
obtain the Pollutant Mass Rate (PMR).
Concentration in Nozzle x Volumetric Flow Rate = Pollutant Mass Rate
On Concentration Basis.
(I>T/VOLSTD) x QQS = PMRp
Assuming the nozzle velocity is greater than the average stack gas velocity
(V greater than V ), the calculated Pollutant Mass Rate will be less than
the true Pollutant Mass Rate because the heavier dust particles will leave
their streamline and not enter the nozzle. If \'n is less than V then the
calculated PMR will be greater than the true PMR.
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CLEM-UP AND ANALYSIS
Clean-up of the EPA train was performed by carefully removing the filter
and placing it in a container marked "Run X, Container A". Distilled
water and brushes were used to clean the nozzle, glass probe and
pre-filter connections. The water wash was placed in a container marked
"Run X, Container B". The volume of water in the impinger and bubblers
(glassware) was weighed in their respective containers to the nearest
0.1 gram. The original weights which included approximately 100 ml. of water
in the bubbler and 100 ml. of water in the impinger were then subtracted
and the difference added with the water weight gain of the silica gel.
This represented the amount of water collected during the run. The water
from the glassware and a water rinse oi: the glassware was placed in a container
marked "Run X, Container C". An acetone rinse of the glassware and all
post-filter glassware (not including the silica gel container) was
performed and placed in a container marked "Run X, Container D".
Analysis of the samples in each container was performed according to the
following:
Run X, Container A - Transfer the filter and any loose particulate from
the sample container to a tared glass weighing dish and desiccated
for.24 hours in a desiccator or constant humidity chamber containing
a saturated solution of calcium chloride or its equivalent. Weighed
to a constant weight and report the results to the nearest 0.1 milligram.
Run X, Container B - Measure tne volume to the nearest 0.1 milliliter.
Transfer water washings from container into a tared beaker and
evaporate to dryness at ambient temperature and pressure. Desiccate
for 24 hours and weigh to a constant weight. Report the result to the
nearest 0.1 milligram.
Run X, Container C - Measure the volume to the nearest 0.1 milliliter.
Extract organic particulate from the water solution with three 25 milliliter
portions of chloroform and three 25 milliliter portions of ethyl ether.
Combine the ether and chloroform extracts and transfer to a tared beaker.
Evaporate until no solvent remains at about 70°F. This can be accomplished
by blowing air that has been filtered through activated charcoal over
the sample. Desiccate for 24 hours and weigh to a constant weight. Report
the results to the nearest 0.1 milligram. After the extraction, evaporate
the remaining water to dryness and report the results to the nearest
0.1 milligram.
i
Run X, Container D - Measure the volume to the nearest 0.1 milliliter.
Transfer the acetone washings to a tared beaker and evaporate to dryness
at ambient temperature and pressure. Desiccate for 24 hours and weigh
to a constant weight. Report the results to the nearest 0.1 milligram.
Blanks were taken on the deionized water, ether and chloroform and
subtracted from the respective sample volumes. The filter paper used
with the EPA train was a Mine Safety Appliance 1106 BH, heat treated glass
fiber filter mat.
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The following sample identification numbers were assigned to samples
collected at U.S. Lime Company, Henderson, Nevada:
RUN NO.
ANALYSIS //
2A
2B
2C
2CX
2D
3A
3B
3C
3C
3D"
x
4A
4B
4C
AC
4D~
x
CLEAN-UP //
13A
13B
13C
13D
14A
14B
14C
14D
ISA
15B
15C
15D
DESCRIPTION
Filter
Front Half Acetone Wash
Back Half Water
Ether-Chloroform Extraction
Back Half Acetone Wash
*
Filter
Front Half Acetone Wash
Back Half Water
Ether-Chloroform Extraction
Back Half Acetone Wash
Filter
Front Half Acetone Wash
Back Half Water
Ether-Chloroform Extraction
Back Half Acetone Wash
5A
5B
50
5CX
5D
16A
16B
Ifir.
16D
Filter
Front Half Acetone Wash
Back Half Water
Ether-Chloroform Extraction
Back Half Acetone Wash
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PROCESS
DESCRIPTION AND PROCESSS
Limestone consists primarily of calcium carbonate or combinations
of calcium and magnesium carbonate with varying amounts of impurities.
Lime is calcined or burned form of limestone, commonly divided into
two basic products - quicklime and hydrated lime. Calcination expels
carbon dioxide from the raw limestone, leaving calcium oxide (quicklime).
With the addition of water, calcium hydroxide (hydrated lime) is formed.
The basic processes in production are (1) quarrying the limestone
raw material, (2) preparing the limestone for kilns by crushing and
sizing, (3) calcining the limestone, and (4) optionally processing the
quicklime further by additional crushing and sizing and then hydration.
The Flintkote Company dolomitic lime plant at Henderson, Nevada,
operates a pressure hydration unit controled by a baghouse.
To prevent condensation of moisture on the bag filters, the offgases
from the hydrator are heated to between 300 and 350°F. by a gas burner
before passing through the baghouse. The pressure drop across the bag-
house ranged from 2.3 to 4.1 in H20. The gas exiting from the baghouse
contains approximately 79% H20 and 15% C02. This gas exits through the
fan exhaust directly to the atmosphere. A summary of the operating
variables is presented in the following Table. Process feed rates were
not obtained because the isokinetic sampling was not successful.
For these tests an extension duct was added to allow sampling according
to EPA prescribed methods. Addition of this ducting increased back
pressure on the baghouse and resulted in condensation of water vapor on
the filters. The exhaust fan shaft speed was increased from the normal
rate of 1835 RPM to 2080 RPM to overcome the condensation problem.
Sampling performed consisted of four one-hour particulate samples.
More extensive testing was abandoned when calculations indicated that
sampling could not be performed in accordance with EPA requirements for
90 to 110 percent isokinetic flow. The extremely high moisture content,
approximately 80% by volume, was the source of this difficulty. Future
attempts to sample this plant must be preceded by a revision of EPA
particulate sampling procedures. Visual observation of the residual
plume indicates that the baghouse is doing a very good job of controlling
particulate emissions.
A five minute .collection of hydrate caught in the baghouse indicated
that it was recovering approximately 100 pounds of lime per hour.
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SUMMARY OF PRESSURE HYDRATOR AND
BAGHOUSE OPERATING DATA
DURING SAMPLING
Date 4/24/74 4/24/74 4/25/74
Test No. 11 3, 4, & 5
Lime Feed Rate (tons/hr)
Water Feed Rate (tons/hr)
Hydrated Feed Rate (tons/hr)
Baghouse Pressure Drop (inches H20) 3.9-4.1 3.3-3.5 2.3-3.35
Baghouse Inlet Temp. (°F) 318-356 324-347 305-351
12
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