Transcript Slide 1

Mercury Monitoring
Barrett Parker, EPA Emissions
Measurement Center
Basis for Mercury Monitoring
• Utility air toxics report to Congress
– EPA made determination for MACT rule
• Proposed rule 1/30 (69 FR 4652)
• New PS included
• Comment period closed 3/30
Electric Utility MACT
• 12 month rolling average mercury
emission limit
• Cap and trade system is an alternative
EMC Involvement
• Collected data on mercury monitors
• Made recommendations for proposal
• Partnered with CAMD, ORD, NIST, EPRI
Test Objectives
• Determined
– Ability for reliable data over time
– Durability, availability, maintenance
requirements
– Suitability of draft PS-12 for CEMS
• Investigated all types of mercury monitors
– Sought options for flexibility and accountability
Monitoring Types
• Periodic Testing (ASTM D 6784-02, M29)
– Reference method
• Continuous collection, delayed analysis
(sorbent tube)
• Continuous collection and analysis
(CEMS)
– Wet conversion, dry conversion, other
Monitoring Types (continued)
• CEMS and sorbent tube selected
– Requested comments on monitoring for
sources emitting less than 25 pounds of
mercury per year
German Experience
• Mercury CEMS on Incinerators
– No requirements for coal-fired power plants
• Visited six incinerators
– One co-fired lignite to produce electricity
• Sources are well controlled
– ESPs, scrubbers, carbon adsorption, and
SCR
• 3rd party instrument certification
Test Phase Description
• Phase I (summer 01)
– 140 MW firing bituminous coal with cold side
ESP
– Use 2 German-certified CEMS
• Phase II (fall 02)
– Same site
– Use 6 CEMS and EPRI monitor
Test Facility During Phase II
• Instruments (left to right)
– Envimetrics, Mercury Instruments, Genesis, Opsis,
Durag, PS Analytical
EPRI’s Carbon Tube Sampler
Test Phase Description
(continued)
• Phase III Pilot (spring 03)
– Low level detection and interference checks
– Pilot scale facility firing natural gas and lignite,
bituminous, and subbituminous coals
– Use 3 CEMS and EPRI monitor
Test Phase Description
(continued)
• Phase III (summer 03)
– 550 MW firing subbituminous coal with dry
FGD, SCR, and baghouse
– 5 CEMS and EPRI monitor
Test Phase Description
(continued)
• Phase IV (fall 03)
– 440 MW firing bituminous coal with wet FGD
and reverse-air baghouse
– 2 CEMS and EPRI monitor
– 3 three-hour test periods
Phase I - Initial
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
RM
8
9
10
11
Phase I - Initial
20
ug / m3
15
10
5
0
1
2
3
4
5
RM
6
7
8
CEMS #1
9
10 11
Phase I – Final
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
RM
Phase I - Final
20
ug / m3
15
10
5
0
1
2
3
4
RM
5
6
7
8
9 10 11 12 13 14 15
Wet CEMS
CEMS #2
Phase II - Initial
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
RM
8
9
10 11 12
Phase II - Initial
20
ug / m3
15
10
5
0
1
RM
2
3
4
Wet CEMS
5
6
7
8
CEMS #2
9
10 11 12
CEMS #3
Phase II - Final
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
RM
8
9
10 11 12
Phase II - Final
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
8
9
10 11 12
RM
Wet CEMS
CEMS #2
CEMS #3
CEMS #4
CEMS #5
Xray CEMS
Phase III - Pilot Scale
20
ug / m3
15
10
5
0
1
3
5
7
9
11
RM avg
13
15
17
Phase III - Pilot Scale
20
ug / m3
15
10
5
0
1
RM avg
3
5
7
Wet CEMS
9
11
CEMS #6
13
15
17
CEMS #4
Phase III - Initial
20
ug / m3
15
10
5
0
1
2
3
4
5
6
7
RM
8
9
10 11
12
Phase III - Initial
20
ug / m3
15
10
5
0
1
2
3
4
5
RM
CEMS #5
6
7
8
CEMS #2
CEMS #6
9
10 11
CEMS #4
Xray MS
12
Selected Phase III – Initial Runs
Run
RM
RM
dup
1
2
1.36
5.34
1.26
3.05
1.2
2.9
1.6
2.3
1.0
2.4
1.08
2.75
4
6
8
11
1.50
6.91
14.27
3.33
1.50
4.22
1.5
4.4
10.1
3.2
1.4
4.7
13.4
3.2
1.5
3.8
11.8
3.1
1.38
4.39
19.00
3.37
3.36
CEMS
#6
CEMS
#2
CEMS
#4
CEMS
#5
3.4
1.1
Xray
MS
Phase III - Final
20
ug m3
15
10
5
0
1
2
3
4
5
6
7
RM
8
9
10 11
12
Phase III - Final
20
ug /m3
15
10
5
0
1
2
3
4
5
RM
CEMS #5
6
7
8
CEMS #2
CEMS #6
9
10 11
CEMS #4
Xray MS
12
DRAFT Phase IV - Initial
20
ug / m3
15
10
5
0
1
2
RM 1 avg
3
RM 2 avg
DRAFT Phase IV – Initial and
Proposed MACT Limit
20
ug / m3
15
10
5
0
1
RM 1 avg
CEMS #6 avg
2
RM 2 avg
10% Limit
3
CEMS #4 avg
DRAFT Phase IV – Initial and
Proposed MACT Limit (Rescaled)
0.4
ug / m3
0.3
0.2
0.1
0
1
RM 1 avg
CEMS #6 avg
2
RM 2 avg
10% Limit
3
CEMS #4 avg
DRAFT Phase IV - Final
20
ug / m3
15
10
5
0
1
2
RM 1 avg
3
RM 2 avg
DRAFT Phase IV – Final and
Proposed MACT Limit
19
ug / m3
14
9
4
-1
1
RM 1 avg
CEMS #6 avg
2
RM 2 avg
10% Limit
3
CEMS #4 avg
DRAFT Phase IV – Final and
Proposed MACT Limit (Rescaled)
0.4
ug / m3
0.3
0.2
0.1
0
-0.1
1
2
3
-0.2
RM 1 avg
CEMS #6 avg
RM 2 avg
10% Limit
CEMS #4 avg
Findings
• No sample loss in 200 feet of line
• Monitors improving between Phases
• Monitors can meet RA requirements of
draft PS-12, but low-level correction
needed
Findings (continued)
• Dual train reference method testing is
important
• Monitors can operate for up to 3 months
with routine maintenance
Products
• Monitoring operational characteristics and
costs
• Data for GPRA report on Mercury CEMS
and coal combustion
• Proposed PS 12A
– Covers only vapor phase (no particulates)
– Designed for fossil fuel fired boiler exhaust
– Allows use of existing equipment
Products (continued)
• Proposed PS 12A (continued)
– Requires at least 9 paired sets of 2 hour
(minimum) runs
– Allows up to 3 sets to be rejected
– Specifies results to be within 20% of
reference method or 10% of MACT limit
– Identifies outliers as
• RSD > 10% if mercury > 1 μg / m3 or
• RSD > 20% if mercury  1 μg / m3
Products (continued)
• Proposed PS 12A (continued)
– Requires measurement error test using NIST
traceable Hg0 and HgCl2 at zero, mid, and
high levels
• Calibration standards from NIST
– Certified elemental mercury in cylinders
• 2, 5, and 20 micrograms per cubic meter
– Ionic mercury to follow (1/06)
Concurrent Activities
• Assist R2 and NJ with PSEG’s NSR
settlement
• Monitor and assist State rulemakings
• Coordinate with ETV mercury CEMS
Phase III
Next Steps
• Respond to proposal comments
• Potential additional testing
– Longer term subbituminous and bituminous
coals with cold side ESP