February 2007
Environmental Technology
Verification Report
TEKRAM INSTRUMENTS CORPORATION
SERIES 3300 MERCURY CONTINUOUS EMISSIONS
MONITORING SYSTEM
Prepared by
Battelle
Batteiie
"Ihe Business o/ Innovation
Under a cooperative agreement with
U.S. Environmental Protection Agency
ET1/ET1/ET1/
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February 2007
Environmental Technology Verification
Report
ETV Advanced Monitoring Systems Center
TEKRAM INSTRUMENTS CORPORATION
SERIES 3300 MERCURY CONTINUOUS EMISSIONS
MONITORING SYSTEM
by
Thomas Kelly
Jan Satola
Zachary Willenberg
Amy Dindal
Battelle
Columbus, Ohio 43201
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Notice
The U.S. Environmental Protection Agency (EPA), through its Office of Research and
Development, has financially supported and collaborated in the extramural program described
here. This document has been peer reviewed by the Agency. Mention of trade names or
commercial products does not constitute endorsement or recommendation by the EPA for use.
This report was prepared by Battelle to summarize testing supported in part by the Illinois
Department of Commerce and Economic Opportunity through the Office of Coal Development
and the Illinois Clean Coal Institute (ICCI). Neither Battelle nor any of its subcontractors nor the
Illinois Department of Commerce and Economic Opportunity, Office of Coal Development, the
ICCI, nor any person acting on behalf of either:
(a) Makes any warranty of representation, express or implied, with respect to the accuracy,
completeness, or usefulness of the information contained in this report, or that the use of
any information, apparatus, method, or process disclosed in this report may not infringe
privately-owned rights; or
(b) Assumes any liabilities with respect to the use of, or for damages resulting from the use of,
any information, apparatus, method, or process disclosed in this report.
Reference herein to any specific commercial product, process, or service by trade name,
trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement,
recommendation, or favoring; nor do the views and opinions of authors expressed herein
necessarily state or reflect those of the Illinois Department of Commerce and Economic
Opportunity, Office of Coal Development, or the ICCI.
Notice to Journalists and Publishers: If you borrow information from any part of this
report, you must include a statement about the state of Illinois' support of the project.
11
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Foreword
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the
nation's air, water, and land resources. Under a mandate of national environmental laws, the
Agency strives to formulate and implement actions leading to a compatible balance between
human activities and the ability of natural systems to support and nurture life. To meet this
mandate, the EPA's Office of Research and Development provides data and science support that
can be used to solve environmental problems and to build the scientific knowledge base needed
to manage our ecological resources wisely, to understand how pollutants affect our health, and to
prevent or reduce environmental risks.
The Environmental Technology Verification (ETV) Program has been established by the EPA to
verify the performance characteristics of innovative environmental technology across all media
and to report this objective information to permitters, buyers, and users of the technology, thus
substantially accelerating the entrance of new environmental technologies into the marketplace.
Verification organizations oversee and report verification activities based on testing and quality
assurance protocols developed with input from major stakeholders and customer groups
associated with the technology area. ETV consists of six environmental technology centers.
Information about each of these centers can be found on the Internet at http://www.epa.gov/etv/.
Effective verifications of monitoring technologies are needed to assess environmental quality
and to supply cost and performance data to select the most appropriate technology for that
assessment. Under a cooperative agreement, Battelle has received EPA funding to plan,
coordinate, and conduct such verification tests for "Advanced Monitoring Systems for Air,
Water, and Soil" and report the results to the community at large. Information concerning this
specific environmental technology area can be found on the Internet at http://www.epa.gov/etv/
centers/center 1 .html.
in
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Acknowledgments
The authors wish to acknowledge the support of all those who helped plan and conduct the
verification test, analyze the data, and prepare this report. This verification was funded in part by
the Illinois Clean Coal Institute (ICCI) under Project No. 04-1/3.2D-1; we appreciate the
involvement and support of Dr. Francois Botha, Project Manager for the ICCI. We acknowledge
the contribution of the Northern Indiana Public Service Company (NIPSCo, a NiSource
company) in hosting this verification at the R. M. Schahfer Generating Station and, in particular,
the efforts of Craig Myers, Bert Valenkamph, and Gary Logan of NIPSCo in support of the field
testing. We also thank Eric Ginsburg and William Grimley of U.S. EPA for their assistance in
setting up a Site Access Agreement among EPA, Battelle, and NiSource. Finally, we would like
to thank Robin Segall of U.S. EPA, Ernest Bouffard of the Connecticut Department of
Environmental Protection, Francois Botha of ICCI, and Craig Myers of NIPSCo for their review
of this verification report.
IV
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Contents
Notice ii
Foreword iii
Acknowledgments iv
List of Abbreviations viii
Chapter 1 Background 1
Chapter 2 Technology Description 2
Chapters Test Design and Procedures 4
3.1 Introduction 4
3.2 Test Facility 5
3.3 Test Procedures 6
3.3.1 Relative Accuracy 6
3.3.2 Linearity 7
3.3.3 Seven-Day Calibration Error 7
3.3.4 Cycle Time 7
3.3.5 Data Completeness 7
3.3.6 Operational Factors 7
3.4 CEM Installation 8
3.5 Verification Schedule 8
Chapter 4 Quality Assurance/Quality Control 11
4.1 OH Reference Method 11
4.1.1 OH Reproducibility 11
4.1.2 OH Blank and Spike Results 13
4.2 Audits 14
4.2.1 Performance Evaluation Audits 14
4.2.2 Technical Systems Audit 15
4.2.3 Data Quality Audit 16
4.3 QA/QC Reporting 16
4.4 Data Review 16
Chapters Statistical Methods 17
5.1 Relative Accuracy 17
5.2 Linearity 17
5.3 Seven-Day Calibration Error 18
5.4 Cycle Time 18
5.5 Data Completeness 18
Chapter 6 Test Results 19
6.1 Relative Accuracy 20
6.2 Linearity 22
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6.3 Seven-Day Calibration Error 23
6.4 Cycle Time 24
6.5 Data Completeness 25
6.6 Operational Factors 26
Chapter 7 Performance Summary 28
Chapters References 30
Figures
Figure 2-1. Tekran Series 3300 CEM 2
Figure 6-1. HgT Readings from the Tekran Series 3300 CEM During the Field Test 19
Figure 6-2. Tekran Series 3300 and OH Mercury Results, June 12-15, 2006 21
Figure 6-3. Tekran Series 3300 and OH Mercury Results, July 10-13, 2006 21
Tables
Table 3-1. Operating and Stack Gas Conditions at Schahfer Station Unit 17 6
Table 3-2. Weekly Test Activities During the Field Perio 9
Table 3-3. Schedule of OH Method Sampling in the Week of June 12, 2006 10
Table 3-4. Schedule of OH Method Sampling in the Week of July 10,2006 10
Table 4-1. OH Results from June 12-15,2006, Sampling Period 12
Table 4-2. OH Results from July 10-13, 2006, Sampling Period 13
Table 4-3. Summary of PE Audit Results 15
Table 6-1. Results from Tekran Series 3300 CEM for Each OH Sampling Run 20
Table 6-2. RA Results for Tekran Series 3300 CEM 22
Table 6-3. Mean Mercury Values from Tekran Series 3300 CEM and OH Method 23
Table 6-4. Tekran Series 3300 Linearity Test Results 23
Table 6-5. Results of Zero/Calibration Stability Tests for Tekran Series 3300 CEM 24
VI
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Table 6-6. Assessment of Cycle Time of the Tekran Series 3300 CEM 25
Table 6-7. Tekran Series 3300 CEM Operational Activities During the Field Test 26
vn
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List of Abbreviations
AC
agl
AMS
ASTM
°C
CEM
CFR
DI
EPA
ETV
°F
FGD
ft3
H202
H2S04
HC1
Hg
HgCl2
Hg°
Hgox
HgT
HNO3
ICCI
KC1
klb/hr
KMnO4
LE
L/min
ug/dscm
ug/L
mL
MW
NIST
NOX
alternating current
above ground level
Advanced Monitoring Systems
American Society for Testing and Materials
degrees Celsius
continuous emission monitor
Code of Federal Regulations
deionized
U.S. Environmental Protection Agency
Environmental Technology Verification
degrees Fahrenheit
flue gas desulfurization
cubic foot
hydrogen peroxide
sulfuric acid
hydrogen chloride
mercury
mercuric chloride
elemental mercury
oxidized mercury
total mercury
nitric acid
Illinois Clean Coal Institute
potassium chloride
thousands of pounds per hour
potassium permanganate
linearity error
liter per minute
microgram per dry standard cubic meter
microgram per liter
milliliter
megawatt
National Institute of Standards and Technology
nitrogen oxides
Vlll
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OH Ontario Hydro
ppm parts per million
PE performance evaluation
QA quality assurance
QC quality control
QMP Quality Management Plan
RA relative accuracy
%RD percent relative deviation
SO2 sulfur dioxide
TSA technical systems audit
UV ultraviolet
V volt
IX
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Chapter 1
Background
The U.S. Environmental Protection Agency (EPA) supports the Environmental Technology
Verification (ETV) Program to facilitate the deployment of innovative environmental
technologies through performance verification and dissemination of information. The goal of the
ETV Program is to further environmental protection by accelerating the acceptance and use of
improved and cost-effective technologies. ETV seeks to achieve this goal by providing high-
quality, peer-reviewed data on technology performance to those involved in the design,
distribution, financing, permitting, purchase, and use of environmental technologies.
ETV works in partnership with recognized testing organizations; with stakeholder groups
consisting of buyers, vendor organizations, and permitters; and with the full participation of
individual technology developers. The program evaluates the performance of innovative
technologies by developing test plans that are responsive to the needs of stakeholders,
conducting field or laboratory tests (as appropriate), collecting and analyzing data, and preparing
peer-reviewed reports. All evaluations are conducted in accordance with rigorous quality
assurance (QA) protocols to ensure that data of known and adequate quality are generated and
that the results are defensible.
The EPA's National Exposure Research Laboratory and its verification organization partner,
Battelle, operate the Advanced Monitoring Systems (AMS) Center under ETV. The AMS Center
recently evaluated the performance of the Tekran Instruments Corporation Series 3300 Mercury
Continuous Emissions Monitoring (CEM) System for determining mercury in stack gas at a coal-
fired power plant. This evaluation was carried out in collaboration with the Illinois Clean Coal
Institute and with the assistance of the Northern Indiana Public Service Company.
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Chapter 2
Technology Description
The objective of the ETV AMS Center is to verify the performance characteristics of
environmental monitoring technologies for air, water, and soil. This report provides results for
the verification testing of the Tekran Series 3300 Mercury CEM. The following is a description
of the Series 3300, based on information provided by the vendor. The information provided
below was not verified in this test.
The Series 3300 (Figure 2-1) measures total mercury (Hgx), elemental
mercury (Hg°), and oxidized mercury (Hgox) in combustion sources. It
has a dual channel stack gas conditioner with selective scrubbing. The
system is designed to separate mercury into elemental and oxidized
species, while removing interfering acid gases, and provide real-time
feedback to optimize mercury reduction technologies. It is designed to
be insensitive to the presence of sulfur dioxide (862), nitrogen oxides
(NOx), carbon monoxide, hydrogen chloride (HC1), and other common
combustion by-products and can operate unattended for extended
periods. In this verification the Series 3300 was programmed to report a
reading of mercury concentration every 2.5 minutes. The CEM
alternated measurements of Hgx and Hg°, providing two successive
readings of Hgx, followed by two of Hg°, two of Hgx, etc.
The Series 3300 consists of a sampling probe, a heated umbilical line, a
sample conditioner, a mercury analyzer, a saturated Hg° vapor
calibrator, and a control system. It uses a stack-mounted inertial probe to
minimize mercury measurement artifacts due to filtering. The sample
flow is then diluted and sent at a high rate through a heated line to the
sample conditioning module. The probe performs automated filter
blowback, multi-point calibrations, and standard additions of mercury
into the sample matrix. The conditioning module speciates the mercury
into elemental and oxidized forms, without using chemical reagents or
solid sorbents. The diluted sample is split into two streams. In the first
stream, a thermal conditioner unit converts all mercury forms into Hg°.
Tekran's patented thermal conditioner/scrubber system is designed to
avoid recombination by the quantitative removal of HC1 and other gases. The second pathway
removes oxidized (water soluble) mercury, leaving only the Hg° to pass through to the converter.
This stream is then subjected to additional conditioning to remove acid gases and excess
humidity from the sample. The two conditioned streams are analyzed using a Tekran Model
Figure 2-1. Tekran
Series 3300 CEM
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2537A mercury vapor analyzer. The analyzer uses gold preconcentration combined with atomic
fluorescence detection.
A calibration source of Hg° allows both multi-point calibrations and standard additions to be
automatically initiated. Both these operations are performed through the entire CEM path,
including all probe filters. The calibration unit generates concentrations of Hg° by using a
saturated mercury vapor source. Precision mass flow controllers dilute the output of this source
to the desired value. The computer provides full control of each module within the system. All
temperatures, flows, and pressures are displayed by the application program and may be set by
authorized users. The system features remote operation and problem diagnosis. The Series 3300
can be audited by introduction of mercury calibration gas standards, which can be delivered
directly to the probe inlet by the umbilical line.
The Series 3300 component rack system (Figure 2-1) is approximately 67 inches high by
31.5 inches deep by 23 inches wide. The associated air purification system occupies a wall-
mountable panel 24 inches by 24 inches in size.
The cost of the Series 3300 CEM as tested was approximately $125,000, excluding the umbilical
line, installation, and training.
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Chapter 3
Test Design and Procedures
3.1 Introduction
This verification test was conducted according to procedures specified in the Test/QA Plan for
Verification of Continuous Emission Monitors (CEMs) and Sorbent-Based Samplers for Mercury
at a Coal-Fired Power Plant.^ CEMs for mercury are designed to determine total and/or
chemically speciated vapor-phase mercury in combustion source emissions. Performance
requirements for mercury CEMs are contained in Chapter 40 of the Code of Federal Regulations,
Part 75 and Part 60 (40 CFR Parts 75 and 60)(2) and require assessment of the performance of
newly installed mercury CEMs only for their determination of Hgx. This total is the sum of
vapor-phase mercury in all chemical forms in the combustion gas, including Hg° and Hgox
(which is primarily mercuric chloride [HgCb]) vapors. In this test the Series 3300 was verified
for its measurement of vapor-phase Hg°, Hgox, and Hgx.
The Series 3300 was verified by evaluating the following parameters:
• Relative accuracy (RA)
• Linearity
Seven-day calibration error
• Cycle time
• Data completeness
Operational factors such as ease of use, maintenance and data output needs, power and other
consumables use, reliability, and operational costs.
Verification of the Series 3300 was conducted in a field test that lasted from June 12 to July 25,
2006, and that included two separate four-day periods of reference mercury measurements
carried out by ARCADIS Inc., under subcontract to Battelle, using American Society for Testing
and Materials (ASTM) D 6784-02, the "Ontario Hydro" (OH) method.(3) RA was determined by
comparing CEM vapor-phase mercury results to simultaneous results from the OH method. RA
of the Series 3300 was determined for HgT and Hg°. Linearity was determined based on
Series 3300 responses to Hg° standards. Calibration error was evaluated by comparing
Series 3300 readings on mercury standard and zero gases performed once each day over a
consecutive seven-day period. Cycle time was evaluated in terms of the response of the
Series 3300 when switching from a zero gas or upscale Hg° standard gas, supplied at the
Series 3300 inlet, to sampling of stack gas. Data completeness was assessed as the percentage of
maximum data return achieved by the Series 3300 over the test period. Operational factors were
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evaluated by means of observations during testing and records of needed maintenance, vendor
activities, and expendables use.
3.2 Test Facility
The host facility for the Series 3300 verification was the R. M. Schahfer Generating Station,
located near Wheatfield, Indiana, approximately 20 miles south of Valparaiso, Indiana. The
Schahfer plant consists of four units (designated 14, 15, 17, and 18), with a total rated capacity of
about 1,800 megawatts (MW). The Series 3300 verification was conducted at Unit 17, which
burns pulverized Illinois sub-bituminous coal and has an electrostatic precipitator and a wet flue
gas desulfurization (FGD) unit. Unit 17 has a typical capacity of about 380 MW. The unit was
operated near this capacity for most of the test period, although the typical daily pattern of
operation was to reduce load substantially for a few hours between late evening and early
morning.
Flue gas from Unit 17 feeds into a free-standing concrete chimney with an internal liner. The top
of the stack is 499 feet above ground level (agl). Emission test ports and penetrations in the
concrete chimney and liner are located at a platform approximately 8 feet wide that encircles the
outside of the stack at 370 feet agl. The stack diameter at the platform level is 22 feet 6 inches, so
the total flow area is 397.6 square feet. The last flow disturbance is at the FGD connection to the
stack liner at 128 feet agl. Thus, the emission test ports were over 10 stack diameters
downstream from the last flow disturbance and nearly six diameters upstream from the stack
exit. Four emission test ports were located at 90° intervals around the circumference of the stack
about 4 feet above the platform at 370 feet agl and were standard 4-inch ports with #125 flanges.
No traversing was done during sampling; both the OH method and the Series 3300 CEM
sampled from a single fixed point inside the inner liner of the stack at their respective port
locations. This arrangement is justified by the absence of stratification observed for SCh and
NOX at this sampling location.
Table 3-1 summarizes key operating and stack gas conditions that characterize Schahfer Unit 17
during the field period, showing the range and average values of key parameters and
constituents. Stack gas pressure was slightly positive at the sampling location.
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Table 3-1. Operating and Stack Gas Conditions at Schahfer Station Unit 17
Parameter
Unitl7Loada
Coal Feed Ratea
Temperature21
Moistureb
NO/
S02a
Hgx vaporb
Average
334 MW
297 klb/hrc
130°F
15.5 %
97 ppmd
193 ppm
0.91 ug/dscme
Range
140-391
140-374
118-140
13.3-16.7
61-165
104-316
0.73-1.22
a: Values calculated from hourly data recorded routinely at the R.M. Schahfer facility, June 12 to July 25, 2006.
b: Values based on measurements made during OH reference sampling periods June 12-15 and July 10-13, 2006.
c: klb/hr = thousands of pounds per hour.
d: ppm = parts per million.
e: ug/dscm = micrograms per dry standard cubic meter.
3.3 Test Procedures
Following are the test procedures used to evaluate the Series 3300 mercury CEM.
3.3.1 Relative A ccuracy
The RA of the Series 3300 CEM was evaluated by comparing its mercury results to simultaneous
results obtained by sampling stack gas with the OH reference method. The OH method is the
currently accepted reference method for mercury measurements in stack gas and employs dual
impinger trains sampling in parallel through a common probe to determine oxidized and
elemental vapor-phase mercury by means of appropriate chemical reagents.(3) In each of two
separate weeks of the field test period, ARCADIS conducted a series of 12 OH runs, each of two
hours in duration, as described in Sections 3.5 and 4.1. The Hg°, Hgox, and HgT determined by
the OH reference method were compared to corresponding results from the Series 3300, by
averaging the successive Series 3300 readings over the period of each OH run. A Tekran vendor
representative operated the Series 3300 throughout all OH sampling.
The OH trains were dismantled for sample recovery in the field by ARCADIS staff, and all
collected sample fractions were logged and stored for transfer to the ARCADIS analytical
laboratory. All sample handling, quality assurance/quality control (QA/QC) activities, and
mercury analyses were conducted by ARCADIS. Subsequent to mercury analysis, ARCADIS
reviewed the data and reported final mercury results from all trains in units of ug/dscm. The
results from the paired OH trains were checked relative to the duplicate precision requirement for
use of the OH data,(3'4) and qualified OH results were averaged to produce the final reference
data used for comparison to the Series 3300 results. RA was calculated as described in Section
5.1 for Hgx and Hg° for each of the two sets of OH reference data. In addition, the averages of
the Series 3300 results for HgT, Hg°, and Hgox were compared to the corresponding averages
from the OH reference method, for each of the two sets of OH data.
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3.3.2 Linearity
Linearity was evaluated by challenging the Series 3300 with three concentrations of Hg° standard
gases using a calibration source built into the Series 3300. These standards were supplied to the
Series 3300 in non-repetitive triplicate through the Series 3300's inlet filter at a rate that
exceeded the Series 3300's inlet flow rate. Each challenge was maintained long enough to
achieve a stable response before moving to the next challenge gas. The triplicate responses of the
Series 3300 at each challenge concentration were averaged, and the average values were then
compared to the known mercury level of the standards. The three challenge concentrations were
initially set at about 4, 8, and 16 ug/dscm, but the linearity test was later repeated at about 1, 2.5,
and 4.5 ug/dscm, as these concentrations were judged more appropriate given the relatively low
mercury level in the Unit 17 stack gas.
3.3.3 Seven-Day Calibration Error
At programmed 24-hour intervals over the period of July 18 to July 24, the Series 3300 was
challenged with zero gas and an Hg° standard concentration of about 4.5 ug/dscm, using the
Series 3300 calibration source. These challenge gases were supplied through the Series 3300's
inlet filter at a rate that exceeded the Series 3300's inlet flow rate. Each such challenge was
maintained long enough to achieve a stable response. Deviation of the Series 3300 zero and
calibration readings from the expected zero or calibration value was assessed to determine
calibration error in the CEM readings.
3.3.4 Cycle Time
Cycle time was determined by monitoring the Series 3300 readings while switching from
sampling of zero gas to sampling of stack gas, and from sampling an Hg° standard to sampling of
stack gas. The former procedure determined the upscale response (or rise) time, and the latter the
downscale response (or fall) time. In each case, the response time was determined as the time
needed to achieve 95% of the change from one stable reading to the next.
3.3.5 Data Completeness
No additional test procedures were carried out specifically to address data completeness. This
parameter was assessed based on the overall data return relative to the total amount of data return
possible for the technology being tested.
3.3.6 Operational Factors
Operational factors such as maintenance needs, data output, consumables use, and ease of use
were evaluated based on observations by Battelle and Schahfer facility staff. A laboratory record
book was maintained at the host facility and was used to enter daily observations on these
factors. Examples of information recorded in the record books are the daily status of diagnostic
indicators for the Series 3300, use or replacement of any consumables, the effort or cost
associated with maintenance or repair, vendor effort (e.g., time on site) for repair or
maintenance, the duration and causes of any down time or data acquisition failure, and operator
observations about ease of use of the Series 3300.
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3.4 CEM Installation
The Series 3300 rack system, argon gas cylinder, and deionized (DI) water container were
installed in an air-conditioned laboratory trailer placed at the base of the Unit 17 stack. The rack
components drew electrical power from two 120V/15A AC circuits inside the trailer.
Compressed air (110 pounds per square inch gauge) was supplied from a compressor located
near the trailer to a wall-mountable air purification panel provided by Tekran and located inside
the trailer. The rack system was connected to the sampling probe on the stack by a heated
umbilical approximately 480 feet in length. Heating of the umbilical was powered by a separate
240V transformer located near the trailer at ground level. The dilution sampling probe was
powered by two additional 120V/15A circuits located near the Series 3300's sampling port on
the platform at 370 feet agl.
Installation of the Series 3300 was conducted by two Tekran field engineers; the more senior of
the two trained the other in the installation procedures as the installation was carried out. The
more junior field engineer then remained on site to conduct instrument checkout and calibration
procedures, and trained Battelle and Schahfer facility staff in routine operation of the Series
3300. That Tekran field engineer operated the Series 3300 CEM during both periods of OH
reference method sampling.
The Series 3300 umbilical and needed utility supplies were in place by June 7, 2006, and the
Series 3300 was first connected to the stack and began sampling stack gas on June 8. However,
the slightly recessed position of the flange on the sampling port was found to prevent the opening
of doors on the CEM's sampling probe, so a port extension was installed that allowed the doors
to clear the port opening on the side of the stack. The use of this extension caused the sampling
point for the Series 3300 probe to be 2.45 feet from the inner wall of the stack, rather than
3.28 feet (1 meter) as prescribed in the test/QA plan.(1) Thus, the Series 3300 sampled stack gas
from a point 10 inches closer to the stack wall than did the OH reference method. This difference
is not expected to affect the comparison of CEM and OH data in Section 6.1 because of the lack
of stratification observed in the Unit 17 stack for other gases (SO2 and NOX).
As noted below, the field verification began with collection of a series of 12 OH samples from
June 12 to 15. The Series 3300 then continued to monitor stack gas continuously until July 25, a
time period that included completion of a second series of 12 OH measurements over the period
of July 10 to 13,2006.
3.5 Verification Schedule
The Series 3300 was verified between June 12 and July 25, 2006, in a field effort that also
evaluated two sorbent-based mercury sampling systems and one other mercury CEM. The
Series 3300 sampled stack gas at Unit 17 throughout that entire period. Table 3-2 shows the
weekly activities conducted prior to and during the field period. Flue gas mercury was sampled
using the OH reference method during the first and fifth weeks of the test period, and the other
weeks were used for routine monitoring by the Series 3300.
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Table 3-2. Weekly Test Activities During the Field Period
Week of Test Activity
May 15 Battelle trailer arrived at Schahfer facility
May 22 Electric power and other utilities established at Schahfer facility
May 29 Series 3300 equipment arrived at site
June 5 Series 3300 installed; trial operations conducted
June 12 First OH reference method sampling period
June 19 Routine operation
June 26 Routine operation
July 3 Routine operation
July 10 Second OH reference method sampling period
July 17 Routine operation
July 24 Routine operation concluded; Series 3300 shut down and removed from
Battelle trailer
Table 3-3 shows the actual schedule of OH reference method sampling completed by ARCADIS
in the week of June 12, and Table 3-4 shows the corresponding schedule of OH sampling
completed in the week of July 10. The OH sampling proceeded efficiently, with three runs
conducted on each of four successive days in each week. In all cases, Tekran personnel and other
participating vendors were informed of the planned start time of each OH run and, in few
instances, the start time of a run was delayed slightly to assure that the technologies being tested
were fully ready to obtain data during the OH run. All OH runs were of exactly two hours
duration, and Tekran personnel were notified as the ending time of each run approached.
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Table 3-3. Schedule of OH Method Sampling in the Week of June 12, 2006
Run Number
1
2
O
4
5
6
7
8
9
10
11
12
Table 3-4. Schedule
Run Number
1
2
3
4
5
6
7
8
9
10
11
12
Date
6/12/06
6/12/06
6/12/06
6/13/06
6/13/06
6/13/06
6/14/06
6/14/06
6/14/06
6/15/06
6/15/06
6/15/06
of OH Method
Date
7/10/06
7/10/06
7/10/06
7/1 1/06
7/1 1/06
7/1 1/06
7/12/06
7/12/06
7/12/06
7/13/06
7/13/06
7/13/06
Start Time
09:15
12:15
15:40
08:15
11:10
14:05
08:10
11:25
14:30
08:20
11:05
13:45
Sampling in the Week of July
Start Time
9:00
11:50
14:55
8:30
11:15
14:00
8:30
11:40
14:15
8:20
11:10
13:45
End Time
11:15
14:15
17:40
10:15
13:10
16:05
10:10
13:25
16:30
10:20
13:05
15:45
10, 2006
End Time
11:00
13:50
16:55
10:30
13:15
16:00
10:30
13:40
16:15
10:20
13:10
15:45
10
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Chapter 4
Quality Assurance/Quality Control
QA/QC procedures were performed in accordance with the Quality Management Plan (QMP) for
the AMS Center(5) and the test/QA plan for this verification test.(1) QA/QC procedures and
results are described below.
One deviation from the test/QA plan occurred due to the inability to position the Series 3300
sampling point at 1 meter inside the inner wall of the stack (see Section 3.4). A deviation form
was prepared and approved noting this occurrence.
4.1 OH Reference Method
This verification test included a comparison of the Series 3300 results to those of the OH
reference method for flue gas mercury.(3'4) The quality of the reference measurements was
assured by adherence to the requirements of the OH method, including requirements for solution
and field blanks, spiked samples, and continuing calibration standards. All OH reference
measurements were made with paired trains, and the percent relative deviation (%RD = the
difference between the paired train results divided by the sum of those results, expressed as a
percentage) of each data pair was required to be < 10% (at mercury levels >1.0 ug/dscm) or
< 20% (at mercury levels < 1.0 ug/dscm).(4) Data not meeting this criterion were excluded from
comparison with the Series 3300 results. The following sections present key data quality results
from the OH method.
4.1.1 OH Reproducibility
The mercury results of the OH stack gas samples are shown in Tables 4-1 and 4-2, for the initial
(June 12-15) and final (July 10-13) weeks of OH method sampling, respectively. Each table
indicates the OH run number and lists the average vapor phase Hgox, Hg°, and HgT results from
the paired OH trains in each run and the %RD of each pair of results. All mercury results are in
ug/dscm, i.e., adjusted to 20°C (68°F) and one atmosphere pressure.
Inspection of Tables 4-1 and 4-2 shows that HgT in the Unit 17 stack ranged from 0.727 to
0.933 ug/dscm in the OH runs conducted in the June 12-15 period, and from 0.787 to
1.215 ug/dscm in the OH runs conducted in the July 10-13 period. The average HgT values in
these periods were 0.815 and 1.008 ug/dscm, respectively (note that one OH result for HgT is
excluded from the latter average because of inadequate dual train precision, as described below).
11
-------
Hg° comprised the great majority of the HgT, consistent with the scrubbing of the Schahfer Unit
17 flue gas. Hg0x never exceeded about 0.09 ug/dscm, and was typically about 5% of the HgT.
The %RD values in Tables 4-1 and 4-2 show generally close agreement between the paired OH
train results for all three mercury fractions. The %RD values are less than about 6.5% in almost
all runs for both Hg° and HgT. The only exceptions were the results for OH Run #8 in the
second set of runs (Table 4-2). The HgT result from that run is excluded from calculations of
RA because the %RD value is outside the 10% criterion for values >1.0 ug/dscm. (Note that the
Hg° result from that run is not similarly excluded because its %RD value is within the 20%
criterion for values <1.0 ug/dscm.) The %RD values for Hgox are slightly higher than those for
HgT and Hg°, presumably due to the low Hgox concentrations, with two %RD values from the
second data set exceeding 20%. RA was not calculated using the Hgox data, so no Hgox values
need be excluded based on %RD.
Table 4-1. OH Results from June 12-15, 2006, Sampling Period
OH Run
1
2
3
4
5
6
7
8
9
10
11
12
Mercury Concentration (ug/dscm) and % RD of Paired Train
Hgox
0.022
0.037
0.038
0.058
0.053
0.048
0.072
0.060
0.055
0.054
0.037
0.032
%RD
15.3
6.8
3.9
3.4
6.6
11.4
1.2
0.5
5.0
0.2
2.5
1.8
Hg°
0.762
0.822
0.821
0.875
0.795
0.684
0.739
0.690
0.819
0.766
0.691
0.748
%RD
3.6
3.8
1.1
2.0
0.6
4.9
2.1
4.3
1.9
3.9
1.1
2.4
HgT
0.783
0.859
0.859
0.933
0.848
0.732
0.811
0.750
0.874
0.820
0.727
0.781
Results"
%RD
3.0
3.4
0.9
1.7
0.1
5.3
2.0
3.9
1.5
3.6
0.9
2.4
a: %RD = difference between paired train results divided by sum of paired train results.
12
-------
Table 4-2. OH Results from July 10-13, 2006, Sampling Period
Mercury Concentration (ug/dscm) and %RD of Paired Train Results3
OH Run
1
2
3
4
5
6
7
8
9
10
11
12
Hgox
0.033
0.037
0.040
0.066
0.029
0.038
0.028
0.084
0.090
0.093
0.092
0.037
%RD
10.1
2.9
3.7
52.3
11.6
2.0
5.7
7.2
6.3
0.6
0.9
22.7
Hg°
0.902
0.823
0.929
0.886
0.757
1.018
1.055
0.997
1.126
0.982
1.014
1.015
%RD
0.8
1.4
1.1
1.4
0.3
6.5
1.2
12.6
0.7
0.1
2.0
0.6
HgT
0.935
0.860
0.969
0.952
0.787
1.056
1.083
1.081b
1.215
1.074
1.107
1.053
%RD
0.4
1.2
0.9
4.9
0.1
6.4
1.3
11.0
0.2
0.1
1.8
0.2
a: %RD = difference between paired train results divided by sum of paired train results.
b: This data point excluded from calculation of RA because %RD value exceeds acceptance criterion.
4.1.2 OH Blank and Spike Results
Analyses were conducted on 18 total samples collected at the Schahfer site from the blank
reagents used in the OH method. Only four of those samples showed detectable mercury, with
concentrations ranging from 0.003 to 0.006 micrograms per liter (ug/L). These blank reagent
concentrations are negligible in comparison to the mercury in impinger solutions recovered from
trains after stack sampling. Those recovered sample concentrations were typically about
0.1 ug/L, 0.2 ug/L, and 3 to 4 ug/L in potassium chloride (KC1) solution, hydrogen peroxide
(H2O2) solution, and potassium permanganate (KMnO4) solution, respectively.
Blank OH sampling trains were prepared and taken to the sampling location on the Unit 17 stack
on three occasions in each week of OH sampling, and were then returned for sample recovery
without exposure to stack gas. These blank OH trains provide additional assurance of the quality
of the train preparation and recovery steps. For the June 12 to 15 sampling period, the total
amounts of mercury recovered from the three blank trains ranged from 0.126 to 0.144 ug,
equivalent to approximately 7% of the typical total amount of mercury recovered from an OH
train after stack gas sampling in that period. Those blank train results correspond to stack gas
mercury concentrations of less than 0.06 ug/dscm. For the July 10-13 sampling period, the total
amounts of mercury recovered from the three blank trains ranged from 0.193 to 0.250 ug,
13
-------
equivalent to less than 10% of the typical total amount of mercury recovered from a train after
stack gas sampling in that period. Those blank train results correspond to stack gas mercury
concentrations of less than 0.1 ug/dscm.
All initial and continuing blank and calibration values from laboratory analysis of the OH
samples met the requirements of the OH method. The recovery of mercury spiked into each
reagent solution recovered from blank and sampled OH trains was also evaluated during
laboratory analysis. Those spike recoveries ranged from 85 to 117% and averaged 97%. The
recovery of mercury spiked into blank train samples as part of the performance evaluation (PE)
audit also met the prescribed criteria, as described in Section 4.2.1.
4.2 Audits
Three types of audits were performed during the verification test: a PE audit of the reference
method, a technical systems audit (TSA) of the verification test procedures, and a data quality
audit. Audit procedures are described further below.
4.2.1 Performance Evaluation Audits
PE audits of the OH method were carried out through procedures implemented at the Schahfer
plant during the field period. Table 4-3 summarizes the procedures and results of the PE audits of
the OH reference method, showing the parameter audited, the date of the audit, the OH and
reference values, the observed agreement, and the target agreement. The OH method
incorporates dual sampling trains, and the equipment used by ARCADIS to carry out the OH
sampling included dual Model 522 Source Sampler meter boxes (Apex Instruments, Fuquay-
Varina, North Carolina) designated by their serial numbers as #2007 and #2008. As a result, for
some parameters Table 4-3 includes results for both meter boxes or for both of the dual OH
trains.
Four PE audits were conducted:
• A Fluke Model 52 II digital thermometer (Serial No. 80730162) was used to audit the probe
temperature measurements made by the #2007 meter box and the stack temperature
measurements made by the #2008 meter box. For this comparison, the appropriate
thermocouple was disconnected from the meter box and connected to the Fluke thermometer.
• A BIOS International Corporation DryCal National Institute of Standards and Technology-
(NIST)-traceable flow measurement standard (Model DC2-B, Serial No. 103777, vendor-
calibrated on May 9, 2006) was used to audit the sample gas flow rate with each of the two
OH meter boxes.
• A set of weights (Rice Lake Weight Set, Serial No. 1JXA) calibrated to ASTM Class 3
standards was used to audit the electronic balance (AND FP-6000, Serial No. 6402118) used
for weighing the OH method impingers.
• Recovery of mercury from OH trains was audited by spiking impingers containing KC1,
H2O2/nitric acid (HNOs), and KMnOVsulfuric acid (E^SC^) reagents in two blank OH
impinger trains, with 1 milliliter (mL) of a prepared mercury solution, in each of the two
14
-------
separate periods of OH sampling. The mercury spiking solution was 2.5 ug/mL Hg in 1%
HNO3 and was prepared by dilution of a NIST-traceable 1,000-ppm (i.e., 1,000-ug/mL)
standard (Aa34n-l, Accustandards, Inc.). In the first week of OH sampling, Impingers 2, 4,
and 5 of Blank Trains 8L and 8R were spiked; and, in the final week of OH sampling,
Impingers 2, 4, and 6 of Blank Trains 7L and 7R were spiked.
Table 4-3 shows that all the PE audit results were within the target tolerances set in the test/QA
plan.(1)
Table 4-3. Summary of PE Audit Results
Parameter
OH temperature
measurement
OH sample flow
measurement
Impinger weighing
Mercury spike
recovery
Date
6/14/06
probe T
stack T
7/11/06
6/14/06
6/14/06
train 8L
imp 2
imp 4
imp 5
train 8R
imp 2
imp 4
imp 5
7/12/06
train 7L
imp 2
imp 4
imp 6
train 7R
imp 2
imp 4
imp 6
OH Result
228°Fa
127°Fb
15.02L/mina
14.58 L/minb
199.72
499.27
2.48 ug
2.02 ug
2.08 ug
2.47 ug
1.97ug
2.10ug
2.24 ug
2.12ug
2.38 ug
2.27 ug
2.33 ug
2.39 ug
Reference
Value
230°F
129°F
14.56 L/min
14.35 L/min
200 grams
500 grams
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
2.5 ug
Agreement
with
Standard
0.29%
0.31%
3.2%
1.6%
0.14%
0.15%
0.8%
19.2%
16.8%
1.2%
21.2%
16.0%
10.4%
15.2%
4.8%
9.2%
6.8%
4.4%
Target
Agreement
2% absolute T
5%
Greater of 1%
or 0.5 gram
25%
25%
25%
25%
25%
25%
25%
25%
25%
25%
25%
25%
a: #2007 meter box.
b: #2008 meter box.
L/min = liters per minute; T = temperature; imp
4.2.2 Technical Systems A udit
-• impinger.
A Battelle Quality Management representative conducted a TSA at the Schahfer test site on
June 14 to ensure that the verification test was being conducted in accordance with the test/QA
plan(1) and the AMS Center QMP.(5) As part of the TSA, test procedures were compared to those
specified in the test/QA plan,(1) and data acquisition and handling procedures, as well as the
reference standards and method, were reviewed. The Quality Management representative
15
-------
observed OH method sampling and sample recovery processes, interviewed ARCADIS
personnel, and observed the PE audit procedures noted above, except for the OH sample flow
and second OH train spiking audits, which were conducted at a later date. Observations and
findings from the TSA were documented and submitted to the Battelle Verification Test
Coordinator for response. None of the findings of the TSA at the Schahfer site required
corrective action. In addition, an internal TSA was conducted in the laboratory charged with
analyzing the OH samples. This TSA was conducted by the ARCADIS independent QA Officer
in the laboratory on-site at EPA in Research Triangle Park, North Carolina, on July 19 and
July 27, 2006. None of the findings of this laboratory TSA required corrective action. Records
from both TSA efforts are permanently stored with the Battelle Quality Manager.
4.2.3 Data Quality Audit
At least 10% of the data acquired during the verification test were audited. Battelle's Quality
Manager traced the data from the initial acquisition, through reduction and statistical analysis, to
final reporting to ensure the integrity of the reported results. All calculations performed on the
data undergoing the audit were checked.
4.3 QA/QC Reporting
Each audit was documented in accordance with Sections 3.3.4 and 3.3.5 of the QMP for the ETV
AMS Center.(5) Once the audit reports were prepared, the Battelle Verification Test Coordinator
ensured that a response was provided for each adverse finding or potential problem and imple-
mented any necessary follow-up corrective action. The Battelle Quality Manager ensured that
follow-up corrective action was taken. The results of the TSA were submitted to the EPA.
4.4 Data Review
Records generated in the verification test received a one-over-one review before these records
were used to calculate, evaluate, or report verification results. Data were reviewed by a Battelle
technical staff member involved in the verification test. The person performing the review added
his/her initials and the date to a hard copy of the record being reviewed.
16
-------
Chapter 5
Statistical Methods
The statistical methods used to evaluate the performance factors listed in Section 3.1 are
presented in this chapter. Qualitative observations were also used to evaluate verification test
data.
5.1 Relative Accuracy
The RA of the Series 3300 with respect to the OH reference method results was assessed as a
percentage, using Equation 1:
RA = _ ^" xlOO% (1)
where Prefers to the difference between the OH reference mercury concentration and the
average Series 3300 reading over the OH sampling period, and x corresponds to the OH
reference mercury concentration. Sd denotes the sample standard deviation of the differences,
while fn-i is the lvalue for the 100(1 - a)th percentile of the distribution with n-1 degrees of
freedom. The RA was determined for an a value of 0.025 (i.e., 97.5% confidence level, one-
tailed). RA was calculated separately for HgT and Hg°, and was calculated separately for the two
periods of OH reference method sampling. All paired OH data meeting the method quality
criteria were eligible for inclusion in the calculation of RA. However, for each of the OH
sampling periods, if more than nine OH results met the acceptance criteria, then selected OH
results could be omitted and RA recalculated. At least nine results were always included in the
calculation. An RA of less than 20% is considered acceptable.(2) Alternatively, when the mean
reference mercury level is less than 5.0 ug/dscm (as in this test), agreement of the overall mean
Series 3300 CEM value within 1.0 ug/dscm of the mean OH value is also considered
acceptable.(2)
5.2 Linearity
The linearity of the Series 3300 response was assessed by comparing its responses to the Hg°
standard concentrations, using Equation 2:
R-A ,~
LE = xlOO (2)
R
17
-------
where LE is the linearity error at each concentration, R is the reference mercury concentration
supplied to the Series 3300, and^4 is the average of the triplicate readings at each concentration.
LE within 10% is considered acceptable.(2)
5.3 Seven-Day Calibration Error
The assessment of calibration error was based on the difference between the Series 3300
responses and the known mercury content of the zero or standard gas. Calibration error was
calculated from the Series 3300 responses to both the zero and calibration gases for each of the
seven consecutive days of this test. Specifically, calibration error was calculated using
Equation 3:
R-A ^
CE = xlOO (3)
S
where CE is the calibration error as a percentage of the Series 3300 span value, R is the reference
mercury concentration supplied to the CEM, A is the Series 3300 response to the reference gas,
and S is the span value of the instrument. Acceptable calibration error is within 5%.(2) However,
for this verification, a span value of 10 ug/dscm was assumed and, therefore, the secondary
acceptance criterion of 1.0 ug/dscm (10% of span) applies.(2) The absolute value of the
differences (R-A) were also reported.
5.4 Cycle Time
The upscale and downscale cycle times (essentially the rise and fall times) of the Series 3300
response were determined as the elapsed time needed to achieve 95% of the final stable reading
after switching from zero gas to stack gas and from a high mercury standard to stack gas,
respectively. The slower (i.e., longer) of the two response times was reported as the cycle time of
the Series 3300. Cycle times not exceeding 15 minutes are acceptable under Part 75.(2)
5.5 Data Completeness
Data completeness was calculated as the percentage of the total possible data return that was
achieved by the Series 3300 over the entire field period. This calculation used the total hours of
data recorded divided by the total hours of data in the entire field period. The field period began
at the start of the first OH method run on June 12 and ended at the shutdown of the CEM on
July 25. For this calculation, no distinction was made between data recorded during stack gas
monitoring and that recorded during calibration or zeroing, or in performance of linearity, cycle
time, and seven-day calibration error testing. The causes of any substantial incompleteness of
data were established from operator observations or vendor records.
18
-------
Chapter 6
Test Results
The results of the verification tests of the Tekran Series 3300 Mercury CEM are presented below
for each of the performance parameters. To illustrate the overall results for this CEM, Figure 6-1
shows all of the Tekran CEM's stack gas HgT readings for the entire test, which spanned over
43 days, from June 12 (designated as Day 0) to July 25 (Day 44). Figure 6-1 shows that the HgT
readings of the Series 3300 were usually below 1 ug/dscm, with most readings centered around
0.8 ug/dscm. A frequent daily pattern of HgT readings is evident, in that lower HgT values were
reported in the early morning hours when the load was reduced on Unit 17. Figure 6-1 also
shows the occurrence of frequent readings of 0 ug/dscm for HgT from the Tekran CEM between
days 15 and 30 (June 27 to July 12). This period includes part of the second set of OH reference
method samples (the x-axis label in Figure 6-1 defines the OH sampling periods).
Tekran HgT
1.5
0.5 -
I.
0 1 2 3 4 5 6 7 8 91011121314151617181920212223242526272829303132333435363738394041424344
Time in Days (Days 0 - 3 span OH1 [12 -15 June 2006], days 28- 31 span OH2 [10 -13 July 2006])
Figure 6-1. HgT Readings from the Tekran Series 3300 CEM During the Field Test
19
-------
6.1 Relative Accuracy
The RA of the Series 3300 with respect to the OH results for HgT and Hg° was calculated using
Equation 1 in Chapter 5. Table 6-1 lists the Tekran results for HgT, Hg°, and Hgox for those time
periods corresponding to each of the OH sampling runs (see Tables 4-1 and 4-2). The Tekran
Hgx and Hg° results in Table 6-1 are each the averages of 24 2.5-minute readings over the
2-hour period of each OH run. The Tekran Hg0x values were determined as the difference
between the average HgT and Hg° readings for each 2-hour OH run. Note that the OH result for
HgT from run #8 in the July 10-13 sampling period was excluded from the calculation because
the %RD value exceeded the acceptance criterion (see Section 4.1.1).
Table 6-1. Results from Tekran Series 3300 CEM for Each OH Sampling Run
Date
6/12/2006
6/12/2006
6/12/2006
6/13/2006
6/13/2006
6/13/2006
6/14/2006
6/14/2006
6/14/2006
6/15/2006
6/15/2006
6/15/2006
7/10/2006
7/10/2006
7/10/2006
7/1 1/2006
7/1 1/2006
7/1 1/2006
7/12/2006
7/12/2006
7/12/2006
7/13/2006
7/13/2006
7/13/2006
OH
Run
1
2
3
4
5
6
7
8
9
10
11
12
1
2
3
4
5
6
7
8
9
10
11
12
Mercury (ug/dscm)
HgT
1.027
0.977
0.900
1.016
0.982
0.958
0.860
0.876
0.931
0.877
0.821
0.851
0.077
0.734
0.800
0.700
0.608
0.609
0.640
0.910
0.908
0.943
0.967
0.945
Hg°
0.946
0.903
0.844
0.914
0.887
0.864
0.773
0.835
0.872
0.829
0.760
0.757
0.040
0.683
0.711
0.584
0.536
0.489
0.533
0.799
0.795
0.843
0.830
0.838
Hgox
0.081
0.074
0.056
0.102
0.095
0.094
0.087
0.041
0.059
0.049
0.061
0.094
0.037
0.051
0.090
0.116
0.072
0.120
0.107
0.111
0.112
0.099
0.138
0.108
The Tekran and OH results are shown graphically in Figure 6-2 for the June 12-15 OH sample
set, and in Figure 6-3 for the July 10-13 sample set.
20
-------
1 1 -,
1 0 -
1
n Q
0 8
n 7
« u-' "
^ 06
0) U'D
3
= 05-
D)
1 04
0 3 -
0 9 -
0 1 -
u.i t
00^
>
4
i
i
!
^ ^
i 2
>
! $
' 4
4
| i
i 1
* 1
>
4
>
] J
[
i
' 1
> ^
> '
]
<
t
L
i Z
>
1 4
<
^ 3
i
1 1
; :
' j
[
* <
4
- j
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> \
>
> <
c
' ^
>
> <
] 1
s
[
* (
4
>
\ i
]
I
^ '
123456 789 10 11 1
OH1 Run Number
»
s
5 « Tekran Hg(T)
• Tekran Hg(0)
A Tekran Hg(ox)
OOH1 Hg(T)
DOH1 Hg(0)
AOH1 Hg(ox)
L
^
2
Figure 6-2. Tekran Series 3300 and OH Mercury Results, June 12-15, 2006
1 ?
1 9
1 1
1 n
0.9 i
_ n «
E
"5i 0 7
3
c n R
^05
n 4 -
0 ?
0 9
0,
n n i
]
~~l ^
§ .
4
1
4
> i
i
t
I 1
L
1 4
1
1
J
1 t
a
4
\ *
1
k
' 1 i
t
i
j
fc 3
4
i
i
L t
^ L
\
4
>
i
I
I
i
^
i « i
I I
s
1
t
4
k
1
L ,
S L
J <
• i
i
\ L
>
T i
^
> 1
1 1
I .
i J
^
1 23456789 10 11 1
OH2 Run Number
, ^Tekran Hg(T)
• Tekran Hg(0)
A Tekran Hg(ox)
OOH2Hg(T)
D OH2 Hg(0)
AOH2Hg(ox)
^
2
Figure 6-3. Tekran Series 3300 and OH Mercury Results, July 10-13, 2006
21
-------
The RA results for the Tekran Series 3300 CEM for HgT and Hg°are shown in Table 6-2, for
both of the two OH data sets. RA values within 20% were achieved by the Series 3300 CEM for
both HgT and Hg° in comparison to the June 12-15 OH data set, but not when compared to the
July 10-13 OH data set. The cause for the latter result appears to be the relatively low readings
obtained from the Series 3300, including readings of 0 ug/dscm for stack gas mercury, over
portions of the test (see Figure 6-1). The Tekran field engineer noted the severely low readings
from the Series 3300 CEM during the first OH run on July 10 (see Figure 6-3) and requested that
that run be excluded from the calculation of RA with the July 10-13 OH data set. He then made
adjustments to the Series 3300 before the start of the second OH run on that day. Consistent with
the application of the equation for RA (Section 5.1), additional Series 3300 data points were also
excluded, so that the RA calculation with the July 10-13 OH data set was performed with the
minimum nine data points for HgT and for Hg°. The additional data points excluded were those
with the poorest agreement between the Series 3300 and OH results. For HgT the one additional
data point excluded was from run #6 (note that run #8 was already excluded because of its %RD
value). For Hg° the two data points excluded were from runs #6 and #7. Table 6-2 shows that
omission of these data points and use of the minimum nine data points resulted in RA values of
28.7% for Hgx and 27.8% for Hg° in comparison to the July 10-13 OH data set.
Table 6-2. RA Results for Tekran Series 3300 CEM
OH Reference Method
Sampling Period
June 12-15
July 10-13a
RA (%)
Hgx Hg°
18.5 15.4
28.7 27.8
a: Results shown based on RA calculation using nine data points.
In addition to the calculation of RA, the mean values of HgT, Hg°, and Hg0x from the OH
method and the Series 3300 CEM were compared for each of the two OH data sets. That
comparison is shown in Table 6-3. For the June 12-15 data set, the comparison in Table 6-3 is
based on all 12 OH and Tekran results. For the July 10-13 data set, the comparison is based on
the nine OH and Tekran results used to calculate RA, as described above. The nine runs used for
the RA calculation were not all the same for different mercury fractions, so the sum of Hg° and
Hgox averages in Table 6-3 may not exactly equal the corresponding HgT average. Table 6-3
shows that the Tekran Series 3300 mean values differed from the OH mean values by 0.027 to
0.213 jig/dscm. All of these differences are well within the 1.0 jig/dscm acceptable difference
from the mean OH value.(2)
6.2 Linearity
The linearity of the Tekran Series 3300 CEM was evaluated over concentration ranges of 4 to
16 jig/dscm and 1 to 4.5 jig/dscm. Table 6-4 shows the results of the linearity tests. Shown in the
table are the dates of the tests, the Hg° standard concentrations, the triplicate CEM responses to
each mercury standard, the mean of the triplicate sets of responses, the difference between that
mean and the standard value, and the resulting LE, calculated using Equation 2 (Section 5.2). As
shown in Table 6-4, the LE of the Series 3300 CEM was within 7% at all three points in both
concentration ranges.
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Table 6-3. Mean Mercury Values from Tekran Series 3300 CEM and OH Method
OH Sampling Period
June 12-15
July 10-13a
Species
HgT
Hg°
Hgox
HgT
Hg°
Hgox
OH Mean
(ug/dscm)
0.815
0.768
0.047
1.011
0.948
0.060
Tekran Mean
(ug/dscm)
0.923
0.849
0.074
0.805
0.735
0.098
Difference
(ug/dscm)
0.108
0.081
0.027
0.206
0.213
0.038
a: Results based on nine OH results.
Table 6-4. Tekran Series 3300 Linearity Test Results
Linearity Test
Date
June 14-15
June 28
Hg° Standard
(ug/dscm)
3.969
7.937
15.86
1.034
2.412
4.478
Tekran
Responses
(ug/dscm)
4.251
4.053
4.285
8.291
7.887
8.484
15.96
15.83
16.58
1.447
0.821
0.640
2.556
2.096
2.087
4.375
4.294
4.136
Tekran
Mean
(ug/dscm)
4.196
8.221
16.12
0.970
2.246
4.268
Difference
(ug/dscm)
0.227
0.284
0.26
0.064
0.166
0.210
LE
(%)
5.7
3.6
1.6
6.2
6.9
4.7
6.3 Seven-Day Calibration Error
Calibration error of the Tekran Series 3300 CEM was determined based on zero and calibration
responses obtained on each of seven consecutive days. Table 6-5 summarizes the results, listing
the zero and calibration responses and the resulting calibration error, calculated according to
Equation 3 (Section 5.3) and expressed as a percentage of the 10 ug/dscm span value. Table 6-5
shows that the Series 3300 exhibited zero readings up to 1.455 ug/dscm (14.6% of span), and
differences from the 4.478 ug/dscm standard of up to 0.314 ug/dscm (3.14% of span). All the
Series 3300 calibration results are within the 5% of span acceptance criterion in Part 75, and well
within the alternate 1 ug/dscm acceptance criterion for a span range of 10 ug/dscm.(2) However,
the zero readings of the Tekran CEM all exceeded the 5% acceptance criterion, and the result
from July 24 even exceeded the 1 ug/dscm tolerance.
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Table 6-5. Results of Zero/Calibration Stability Tests for Tekran Series 3300 CEM
Difference
Zero from
Readings Standard"
Date (jig/dscm) (jig/dscm)
July 18 0.814 0.814
July 19 0.575 0.575
July 20 0.895 0.895
July 21 0.679 0.679
July 22 0.738 0.738
July 23 0.976 0.976
July 24 1.455 1.455
a: Relative to standard concentration of zero.
b: Relative to span value of 10 jig/dscm.
c: Relative to standard concentration of 4.478
Zero
Error
(%)b
8.14
5.75
8.95
6.79
7.38
9.76
14.6
jig/dscm.
Calibration
Readings
(jig/dscm)
4.251
4.393
4.544
4.265
4.327
4.559
4.792
Difference
from
Standard"
(jig/dscm)
0.227
0.085
0.066
0.214
0.151
0.081
0.314
Calibration
Error (%)b
2.27
0.85
0.66
2.14
1.51
0.81
3.14
6.4 Cycle Time
The cycle time of the Tekran Series 3300 CEM was assessed by inspection of periods when the
CEM was switched between sampling of calibration or zero gas and sampling of stack gas. This
assessment was complicated by the automated sequencing of the Series 3300 in continuous
monitoring, which alternated between two readings of HgT and two of Hg°; by the integrated
sampling mode of the Series 3300, which produced new mercury readings at 2.5-minute
intervals; and by noise in the CEM readings at the low stack gas mercury levels observed.
However, data were sufficient to allow an estimate of cycle time. Table 6-6 presents the data
from periods used to assess the cycle time of the Series 3300, showing the date, time, and value
of the Tekran Series 3300 readings in ug/dscm; the readings chosen as the initial and final
readings, and readings near the 95% change level; and the estimate of cycle time (either fall time
from calibration gas to stack gas or rise time from zero gas to stack gas).
Table 6-6 shows that the Tekran Series 3300 HgT cycle time (both fall and rise time) was
estimated to be 7.5 to 10 minutes. The Series 3300 response actually rose slightly for one reading
upon switching from calibration gas to stack gas, and similarly the Series 3300 reading initially
overshot the stack gas HgT level upon switching from zero gas to stack gas. These readings are
apparently artifacts of the switching of gases supplied to the Series 3300 probe.
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Table 6-6. Assessment of Cycle Time of the Tekran Series 3300 CEM
Date Time
6/13/06 17:35:01
17:37:31
17:40:01
17:42:31
17:45:01
17:47:31
17:50:01
17:52:31
17:55:01
17:57:31
18:00:01
18:02:31
7/11/06 21:42:31
21:45:01
21:47:31
21:50:01
21:52:31
21:55:01
21:57:31
22:00:01
22:02:31
Tekran
Reading
(ug/dscm)
17.47a
17.84a
10.06a
2.35a
1.39b
1.21b
1.51a
1.47a
1.00b
1.25a
1.30a
0.00a
1.15a
0.90a
0.76a
0.73a
0.51b
0.76b
0.85a
0.81a
Comments
Initial HgT reading
93.5% decrease
98.7% decrease
Final HgT reading
Initial HgT reading
93.8% increase
105% increase
Final HgT reading
Cycle Time
Estimate
Fall time 7. 5 to
10 minutes (3 to
4 measurement
intervals)
Rise time 7.5 to
10 minutes (3 to
4 measurement
intervals)
a: HgT
b:Hg°
6.5 Data Completeness
The total duration of the field test was from the start of the first OH sampling run on June 12 to
the shutdown of the CEMs on July 25, a total of 43.4 days. The Tekran CEM operated for all of
that period, and suffered minimal down time or loss of data, recording 24,955 readings. The
maximum number of 2.5-minute readings possible was 24,977, so the Series 3300 achieved
99.9% data recovery. However, not all of the Tekran CEM readings were valid measurements of
stack gas mercury. A more detailed breakdown of the Series 3300 operational activity is shown
in Table 6-7.
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Table 6-7. Tekran Series 3300 CEM Operational Activities During the Field Test
Activity
Number
Stack Gas Monitoring
(Stack Gas Readings of 0 ug/dscm)
Filter Blowback
Calibration/Zeroing/Other Checks
a: These readings are a subset of the
b: Maximum number of 2. 5 -minute
Totals
21,953 total stack gas
readings was 24,977.
of Measurements
21,953
(4,643 )a
622
2,380
24,955b
readings.
Days
38.1
(8.1)
1.1
4.1
43.3
Percent of
Time
87.9%
(18.6%)
2.5%
9.5%
99.9%
Table 6-7 shows that operational activities for the Tekran CEM during this test consisted of
38.1 days (87.9% of the field period) of routine monitoring of stack gas mercury; 1.1 days
(2.5%) conducting or re-stabilizing after programmed filter blowback; and 4.1 days (9.5%) in
calibration, zeroing, and other programmed QC procedures. However, for 8.1 days of the routine
stack gas monitoring (18.6% of the total field time), the Tekran Series 3300 produced erroneous
readings of "0" ug/dscm on stack gas. Thus, non-zero stack gas mercury readings were achieved
for at most 69.3% of the field period.
6.6 Operational Factors
The Tekran Series 3300 CEM used high purity argon gas at a rate of about 200 cubic centimeters
per minute, consuming one standard cylinder of argon (i.e., approximately 200 cubic feet [ft3] of
gas) in about one month of continuous operation. This CEM also used DI water at a rate of about
3 L per day. The Series 3300 required both 240 and 120V AC power, and required power
connections both at the ground and aloft at the stack sampling port. Facility compressed air was
also required. The Series 3300 used software that controlled all monitoring, calibration, and data
acquisition functions and provided a detailed display of current readings and activity that was
valuable in the field. For example, it was possible to tell at a glance what the most recent
mercury reading was; whether it was of Hgx or Hg°; and whether a zero, calibration, blowback,
or other QA activity was in progress. A running plot of mercury data could also be displayed.
This software is accessible by means of an analog phone line through a modem built into the
Series 3300's computer, and the vendor frequently used this means of access. The data system
automatically recorded a detailed record of all measurements and operations conducted over each
day of monitoring (midnight to midnight).
The Tekran CEM operated reliably throughout the test period, in the sense of having negligible
down time. However, several problems did require substantial attention by Tekran repre-
sentatives over the course of test. These included adjustments to the internal filter temperature,
probe dilution ratio, and duration of daily zeroing and replacement of the ultraviolet (UV) lamp
in the mercury analyzer. The most recurring problem was the occurrence of low or zero readings
for mercury. Tekran was first notified of this issue on June 27 after the problem was noticed by
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Unit 17 field staff. Efforts to diagnose the problem via modem connection were unsuccessful,
and Tekran personnel then suspected a plug in the sampling probe. In early July, efforts were
made to clean the probe, culminating with the probe being pulled from the stack on July 9 and
reinstalled at a slight downward angle. At this time the voltage of the UV lamp was also adjusted
from 14 V to about 8 V. However, the erroneous low readings persisted, and on July 10 the
Tekran representative concluded that the photomultiplier voltage also should have been adjusted
when the lamp voltage was adjusted. The Tekran CEM readings during the first OH run on
July 10 were severely low, and the Tekran representative requested that this run be omitted from
calculation of JAA. He continued to work on the problem, but it was apparently not corrected
until the UV lamp was again replaced on July 12. After that date, the erroneous zero readings
were not seen again in the Tekran data (see Figure 6-1).
Tekran representatives spent a total of about 21 man-days at the Schahfer Unit 17 test site during
the field test and controlled the Series 3300 CEM remotely via modem in other periods. Most of
the on-site days were during the initial installation and startup, when two Tekran representatives
were on site.
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Chapter 7
Performance Summary
The RA of the Tekran Series 3300 Mercury CEM was 18.5% for HgT and 15.4% for Hg°, based
on comparison to 12 OH reference results obtained at the start of the six-week field test. The
overall average HgT, Hg°, and Hgox values from that first set of OH data were 0.815, 0.768, and
0.047 ug/dscm, whereas those from the Series 3300 were 0.923, 0.849, and 0.074 ug/dscm, with
resulting differences of 0.108, 0.081, and 0.027 ug/dscm, respectively. The RA of the Series
3300 was 28.7% for HgT and 27.8% for Hg°, based on comparison to nine OH reference results
obtained at the end of the six-week field test. The overall average HgT, Hg°, and Hgox values
from that set of OH data were 1.011, 0.948, and 0.060 ug/dscm, whereas those from the
Series 3300 were 0.805, 0.735, and 0.098 ug/dscm, with resulting differences of 0.206, 0.213,
and 0.038 ug/dscm, respectively.
The LE of the Series 3300 was 4.7 to 6.9% when tested over the range of about 1 to 4.5 ug/dscm
and 1.6 to 5.7% when tested over a range of about 4 to 16 ug/dscm.
The seven-day calibration error of the Series 3300 was evaluated with zero gas and with a
calibration gas of about 4.5 ug/dscm Hg°. Error in zero readings ranged from 5.75 to 14.6% of
span, and error in calibration gas readings from 0.66 to 3.14% of span, in both cases relative to
an assumed 10 ug/dscm span value.
Cycle time of the Series 3300 was estimated to be 7.5 to 10 minutes, in switching from either
zero gas or span gas to sampling of stack gas. The Series 3300 provided a mercury reading every
2.5 minutes, so the cycle time was estimated as a multiple of this integration time.
Data completeness of the Series 3300 was 99.9% over the six-week field test, in the sense that
the CEM operated with minimal down time and provided readings at 2.5-minute intervals
throughout the test. However, not all readings were valid measurements of stack gas mercury.
Frequent erroneous readings of 0 ug/dscm were reported by the Series 3300 in a portion of the
field period, amounting to 8.1 days of such readings (18.6% of the field test duration).
The Series 3300 used one standard cylinder of argon (about 200 ft3 of gas) in about one month of
continuous operation. The Series 3300 also used DI water at a rate of about 3 L per day; required
both 240 and 120V AC power, with connections for the latter both at the ground and aloft at the
stack sampling port; and required connection to facility compressed air. The Series 3300 is
controlled by software that can be accessed locally or remotely and provides rapid control of all
instrument operations and detailed information on mercury results and instrument functions. The
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only recurring problem with the Series 3300 was the frequent reporting of 0 ug/dscm for stack
gas mercury over approximately two weeks of the field period. This problem apparently was
related to the UV lamp in the mercury analyzer of the Series 3300 and was ultimately solved by
replacement of the lamp and proper adjustment of lamp voltage.
The cost of the Tekran Series 3300 Mercury CEM as tested was approximately $125,000,
excluding the umbilical line, installation, and training.
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Chapter 8
References
1. Test/QA Plan for Verification of Continuous Emission Monitors and Sorbent-Based
Samplers for Mercury at a Coal-Fired Power Plant, Battelle, Columbus, Ohio, May 18,
2006.
2. Code of Federal Regulations, 40 CFR Part 75, including Appendices A through K, and
Part 60, July 2005.
3. Standard Test Method for Elemental, Oxidized, Particle-Bound and Total Mercury in Flue
Gas Generated from Coal-fired Stationary Sources (Ontario Hydro Method), ASTM D
6784-02, American Society for Testing and Materials, West Conshohocken, PA, June 2002.
4. Performance Specification 12A - Specifications and Test Procedures for Total Vapor Phase
Mercury Continuous Emission Monitoring Systems in Stationary Sources, 40 CFR Part 60
Appendix B, July 2005.
5. Quality Management Plan (QMP) for the ETV Advanced Monitoring Systems Center,
Version 6.0, U.S. EPA Environmental Technology Verification Program, Battelle,
Columbus, Ohio, November 2005.
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