Compliance of Biomass Plants with PM2.5 and MACT Emission Limits: The Risks of Emission Testing

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1 Source Emissions Testing and Emissions Specialists Compliance of Biomass Plants with PM2.5 and MACT Emission Limits: The Risks of Emission Testing Craig Thiry Business Development Director Kevin Crosby Technical Director Oregon California - Arizona AWMA Puget Sound Chapter March 27, 2012

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4 Boiler MACT rule delay denied in Senate vote Mar 8, 2012 The U.S. Senate March 8 voted for the EPA Regulatory Relief Act, also known as the Collins Amendment to the Highway Bill of In order for the bill to pass, 60 votes were required under a previous agreement between senators. The vote means that current rulemaking on the ICI-Boiler Most Available Control Technology (ICI-Boiler MACT) can continue without Congressional delay. A finalized Boiler MACT rule is expected to be issued within 90 days. EPA said it planned to present a less costly Boiler MACT rule to the boiler industry by spring of The rule was initially issued in March 2011 and stopped through a stay provision issued by the EPA in May EPA is issuing no-action assurance letters to those affected by the MACT rules. Randy Rawson, president and CEO of the American Boiler Manufacturers Association, said while he has been a longtime supporter of letting the rulemaking continue, he believes the issue is not over. It is likely to reappear in some form or another any time before the rules are finalized by US EPA; those opposed to the rulemaking will be energized by the closeness of the vote, Rawson said.

5 If you take one thing with you... A POLLUTANT IS NOT DEFINED BY THE CHEMICAL OR THE PHYSICAL CHARACTERISTICS OF THE POLLUTANT (e.g. PM2.5, CPM) IT IS DEFINED BY THE SAMPLING METHODOLOGY USED TO COLLECT THE POLLUTANT (and the sampler?)

6 PM and PM2.5 Measurement Challenges Lowering emission limits Addition of Condensable Particulate Matter (CPM) Bias in the measurement of CPM emissions (historical and new methods) Test methods may not measure low enough to quantify low-concentration emissions 1970 s Limits As high as 125 mg/m 3 (Filterable PM only) Limits Today 2 to 15 mg/m 3 (Filterable + Condensable)

7 Emission Limits lb/mmbtu, NSPS, NSR in CA & OR and MACT

8 EPA 5/17 with Old EPA 202 Test Method Filterable/front half & condensable/back half/cpm

9 New EPA 202 Impinger Train

10 PM2.5 Compliance Challenges Front-Half or Filterable PM2.5 Old MACT 0.03 lb/mmbtu for ALL Existing Units lb/mmbtu for ALL New Units Reconsidered MACT lb/mmbtu for Dry Stoker 0.32 lb/mmbtu for Wet Stoker and so on for other combustion types The reconsidered standards are a great relief, but still pose challenges for some facilities

11 Drivers for Testing PM2.5 Compliance Permit Limits New Source Review (NSR), Prevention of Significant Deterioration (PSD) Data for Future Needs Baseline data for future permitting Emission inventories and inputs to AQ models Require accurate data for: - Primary, Directly emitted PM2.5 - Gaseous Precursors to formation of Secondary PM2.5 (SO 2, NO X, VOC, NH 3 )

12 PM2.5 Test Methods Filterable Particulate Matter (FPM) collection is straightforward (not an issue or problem) Condensable PM collection can include artifacts interferences from gases Salts form from the gases that dissolve in the water that condenses in the sampling train and these get counted as CPM Example: Ammonia and SO 2 dissolve (as does O 2 ) to form ammonium sulfate (NH 4 ) 2 SO 4 which is measured as CPM

13 Maximizes air to liquid contact

14 Filterable and Condensable PM2.5 CPM is usually much higher than the FPM May be about the same as FPM, may be around 10 times higher If you have significant SO 3, HCl with NH 3 or semi-volatile organic emissions, these ARE CPM Otherwise, your test results will depend on your SO 2 and NH 3 emissions.

15 Biomass and Wood Boiler CPM emissions by EPA Old 202 and New 202 Linear Scale, vs. SO2 CPM emission rate, lb/mmbtu SO2 concentration, ppm vol dry Old 202 New 202 Linear (Old 202) Linear (New 202) These results are from a variety of wood and biomass fired boilers. Note the wide range of emission rates in lb/mmbtu. Most of these results would be within the MACT limits for PM2.5 but some are barely within.

16 CPM Emission Measurement Comparison by Old and New EPA Method CPM emission rate, lb/mmbtu Old 202 New 202 Stack gas SO2, ppm vol dry Results are arranged according to SO 2 concentration, X-axis is not linear. These are from a variety of sources with more variables than just the SO 2 concentration. The highest SO 2 sources did not have the highest results. NH 3 slip > 2 ppm can drive results high even at rather low SO 2.

17 Risk and Mitigation Failure to meet emission limits even with properly working control devices Artificially high emission factor for PM2.5 may cause permitting problems in the future Know and understand your process and emissions NH3, SO2, etc. Educate your operators High-quality tests can help minimize the problems with results Pre-compliance testing can help understanding

18 Can we Improve the Situation? Reduce Ammonia Slip (below about 2 ppm) Correct the results for ammonium salts - some have suggested using controlled condensation test results for the inorganic fraction Use a Dilution method (measure filterable and condensable together) - EPA conditional test method CTM-039

19 Controlled Condensation ASTM is working on a standard method EPA has accepted NCASI methods for some uses (CTM-013) CC accurately measures SO 3 and SO 2 from almost any type of source SO 3 would count as CPM; SO 2 would not! This can provide understanding of how much CPM to expect, and how much of the Method 202 measurement is artifact.

20 Dilution Sampler Concept Stack emissions of Primary PM2.5 Emissions into a "virtual" stream of air Stream of air Particles + Condensables + Gases Photochemistry Secondary + Primary PM2.5 Ambient sampler PM2.5 filter Stack sampling of Primary PM2.5 by CTM-039 Sample "emitted" into a stream of air Primary PM2.5 - Particles and Condensables (and Gases) Stream of air Sampled through filter same as Ambient sampler Gases remain as gases, no secondary PM2.5

21 EPA s CTM-039 Designed to emulate dilution of stack emissions in ambient air Condensables form in the same way as in actual emissions EPA s Gold Standard Primary PM2.5 particles and CPM - all sampled together (like ambient sampling) Shows promise the results of comparative studies are encouraging Disadvantage: Expensive new equipment, still rather experimental

22 Update: Area Source Boiler MACT Tune-up Deadline The final Area Source Boiler MACT requires a tune-up for subject boilers by March 21, 2012 The proposed reconsideration rule specifies that all existing boilers subject to the tune-up requirement would have until March 21, 2013 to demonstrate initial compliance EPA has issued a no action assurance letter (NAA) on March 13, To continue following these developments and for information pertaining to the Area Source Boiler MACT rule go to:

23 CO Results for Various Boilers CO Plant ppmvd O2 dry lb/mmbtu CO results vary greatly from plant to plant

24 HCl Results for Various Boilers HCL Plant ppmvd lb/mmbtu 1 <0.137 <2.6 E^-04 2 <0.161 <2.22 E^ N/A HCl results vary greatly from plant to plant

25 Multiple Metals Low Detection Limits Analyite (lb/mmbtu) Plant 1 Plant 2 Plant 3 Antimony (Sb) * Arsenic (As) * Barium (Ba) Beryllium (Be) * * * Cadmium (Cd) * Chromium (Cr) Cobalt (Co) * * Copper (Cu) Lead (Pb) Manganese (Mn) Mercury (Hg) * * * Nickel (Ni) Phosphorus (P) Selenium (Se) * * * Silver (Ag) * Thallium (Tl) * * Vanadium (Vn) N/A N/A Zinc (Zn) *Samples were Non-Detect Plants are looking for very low detection limits

26 Polychlorinated Dibenzo- Dioxin/Polychlorinated Dibenzo-Furan (PCDD/PCDF) Plant 1 Plant 2 Plant 3 CA Toxics EPA Toxics WHO Toxics CA Toxis EPA Toxics Total PCDD Toxic Equivalent, pg/m Total PCDD Toxic Equivalent, 7% O Total PCDF Toxic Equivalent, pg/m Total PCDF Toxic Equivalent, 7% O Total PCDD/PCDF Toxic Equivalent, pg/m Total PCDD/PCDF Toxic Equivalent, 7% O Plants are looking for even lower detection limits for PCDD/PCDF 1pg = g

27 Conclusions Know and understand your process and emissions NH3, SO2, etc. Reduce Ammonia Slip (below about 2 ppm) Educate your operators High-quality tests can help minimize the problems with results Ensure your Source Tester knows about the new method

28 Questions? If you got stack provide your contact information and get your free got stack shirt or the Avogadro 8 gig USB Mole Craig Thiry Business Development Director Source Emissions Testing and Emissions Specialists