Mercury Monitoring Update for the Utility MACT Working Group

Barrett ParkerOAQPS03/04/03

Overview

• Purpose• Background• Phase I• Phase II • Planned Phase III

Purpose

• Explain– Where we are– How we got here– Where we intend to go

• EPA’s goal– Options for continuous mercury monitoring

• Maximum flexibility• Minimum cost

Background Partners

• External– NIST– DOE– ETV– EPRI

BackgroundMonitor Types

• One time– Manual reference test method (wet)

• Ontario Hydro is ASTM approved • Real time

– Wet CEMS• Automated version of reference method

– Dry CEMS• Proprietary catalysts and CVAAS or AFS

– Other CEMS • Carbon impregnated paper tape x ray fluorescence

• Time delayed– Carbon tube (EPRI)

BackgroundGerman Experience

• Mercury CEMS on Incinerators – No requirement 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

BackgroundTechnical Concerns

• Stability, reliability, and availability of calibration standards

• Loss of sample in handling system

• Species conversion

Background Concerns

• CEMS costs, complexity, performance

• CEMS application on US sources

• Fuel, equipment, control uniqueness

• Availability

Background Work plan

• Phase I - summer 01– Test 2 German certified CEMS at minimally controlled

coal-fired power plant

• Phase II - fall 02– Test 7 CEMS and EPRI’s carbon tube at minimally

controlled coal-fired power plant

• Phase III - spring 03 to spring 04– Test most promising CEMS and EPRI’s carbon tube

at well controlled coal-fired power plant(s)

Phase I Description

• Installed 2 German certified dry CEMS at a full scale, representative power plant– 140 MW PC with cold-side ESP firing bituminous– Plant type provides most challenge to CEMS

• Collected data over 5 months with 2 Relative Accuracy Test Audits (RATAs)– Total mercury using Ontario Hydro

• Included ORD’s wet CEMS

Phase IInitial RATA

1 2 3 4 5 6 7 8 9 10 11Run Number

0

5

10

15

20

Ontario Hydro Dry CEMS #1

Phase IFinal RATA

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Run Number

0

5

10

15

20

Ontario Hydro Wet CEMS Dry CEMS #2

Phase IResults

• Collected evidence of stable, reliable calibration standards– Elemental and ionic

• Demonstrated no mercury loss in sample handling system

• Showed wet CEMS met draft RATA criteria

Phase IIDescription

• Continued with 2 Phase I CEMS– Modified dry CEMS converter– Relocated wet CEMS to trailer

• Tested 4 new CEMS – 3 with differing dry conversion systems– 1 with plasma emission spectroscopy

• Included EPRI’s carbon tube sampler • Gathered reliability and operational data

Phase IIMonitor Trailer

• Instruments (left to right)– Envimetrics, Mercury Instruments, Genesis, Opsis,

Durag, PS Analytical

Phase IIEPRI’s Carbon Tube Sampler

Phase II Results (ready spring 03)

• Reliability, cost, and operational dataover 3 months

• Analysis of – Differing approaches

• Plasma emission spectroscopy and X ray fluorescence

– Differing interference minimization• Larger volume systems and manual response

correction

Phase IIInitial RATA (preliminary)

1 2 3 4 5 6 7 8 9 10 11 12Run Number

0

5

10

15

20

Ontario HydroWet CEMS

Dry CEMS #2Dry CEMS #3

EPRI

Phase IIFinal RATA (preliminary)

1 2 3 4 5 6 7 8 9 10 11 12Run Number

0

5

10

15

20

Ontario HydroWet CEMSDry CEMS #2

Dry CEMS #3Dry CEMS #4Dry CEMS #5

X ray CEMSEPRI

Planned Phase III

• Determine low level, co-pollutant impacts (by Jun 03)

• Manage NIST standards development (by Jan 06)

Planned Phase III

• Evaluate CEMS at better controlled full scale power plant (by Aug 03)– Dry FGD with SCR and baghouse firing

subbituminous coal– Evaluate carbon tube sampler with EPRI

Planned Phase III

• Evaluate CEMS at full scale power plants (by Jan 04)– Wet scrubber firing bituminous coal or– Uncontrolled unit firing subbituminous coal