William R. Roberson RMB Consulting & Research, Inc.

1 William R. Roberson RMB Consulting & research , EPRI CEM Users Group MeetingRaleigh, North Carolina May 8-9, 2013 LEE Qualification For Hg Overview How To Qualify for LEE Status Special Considerations Example Calculations and Qualification Data Questions??? EPRI Project Opportunity Hg Monitoring Status UpdateRMB Consulting & research , Environmental Services to Industry NESHAP National Emission Standard for Hazardous Air Pollutants: Coal and Oil- Fired Electric Utility Steam Generating Units Establishes Hg Emission Limit for Existing Coal Units lb/TBtu or non low rank coal lb/TBtu or low rank coal Establishes Hg Emission Limit for Existing Oil Units or Consulting & research , Environmental Services to Industry NESHAP or Mercury Air Toxic Standard (MATS) Requires: Continuous Compliance of Emission Limit Installation of Continuous Mercury Monitor (CMM) Hg CEMS Sorbent Trap Monitor ( PS-12B) EXCEPTION.

2 Sources that Qualify for LEE StatusRMB Consulting & research , Environmental Services to Industry What is LEE? Low Emitting EGU (Electric Generating Unit) Why Qualify? No Continuous Compliance Required No Hg CEMS or Sorbent Trap Monitor No monitor = minimal labor and reporting requirements Who Can Qualify? All Existing EGUs Scrubber equipped units cannot have a bypassRMB Consulting & research , Environmental Services to Industry Once We Qualify, Are We Always LEE Unit? NO! Must Maintain LEE Status Annual Performance Test Must demonstrate qualification every year.

3 This is different than all other pollutants covered in MATS rule! If LEE Status is Lost, Then What? Commence quarterly stack testing 6 months to install and certify CMM LEE Status can be regained if 3 yrs of testing and CMM data meet LEE criteriaRMB Consulting & research , Environmental Services to Industry Stack Testing Requirements Reference Method 30B Hg Testing Must cover 30 boiler operating days No start-up/shutdown exemption Nominally equal length test runs Each test run can be up to 10 days long Qualify if Results Demonstrate.

4 < 10% of applicable emissions standard or Potential mass emissions < lb/yr and below applicable emissions standard Recommend mass emission approachRMB Consulting & research , Environmental Services to Industry Sampling Location Within 10% of centroidal area of stack Different from typical Method 30B Test Run Duration Up to 10 days per test run ( only 3 paired trains) Spike retention/Breakthrough concerns Moisture Determination Options Method 4 Default Moisture ALT-091 RMB Consulting & research , Environmental Services to Industry Sample within 10% of centroidal areaRMB Consulting & research , Environmental Services to IndustryStack Diameter = 30 ftR = 15 ftArea = 707 ft210% of Area = ft2r = ftProbe Length > (R r ) Probe Length > ft(Typical lengths are 6-8 ft)

5 RrProbe Length Method 30 Considerations Test Run Durations Very little is known about long term 30B runs Concerns about spike recovery for long term sampling Most experience is with PS-12B where spike is in Section 3 Suggest engineering runs to ascertain longest possible run times with goal being 10 days. May need to be shorter due to spike recovery or breakthrough issuesRMB Consulting & research , Environmental Services to Industry Method 30 Considerations Total Number of Runs and Spiking??? May be as few as 3 ( 10 days per run) If 3 runs only, all 3 will need to be spiked for field spike recovery calculation May require more runs if spike recoveries or breakthrough are problematic Unclear what the impact of additional runs will be If 5 runs are required, do runs 4 and 5 have to be spiked?

6 ?? EPA may need to clarify the requirements Method language would suggest not if field spike recovery was successfulRMB Consulting & research , Environmental Services to Industry Moisture Determinations Method 30B requires Method 4 for each run NOT PRACTICAL Default, fuel specific default moisture Biased low by up to 10% on wet stacks New Alternative Method (ALT 091) Proposed by WRR for LEE Qualification purposes Essentially treats front end of RM 30B as RM 4 Recommended for saturated (wet) stacksRMB Consulting & research , Environmental Services to Industry Moisture Determinations ALT-091 Gravimetric determination from front end of Method 30B train Compare gravimetric to Psychrometric chart Use lower of 2 moistures per section 12 of RM 4 Recommend using this approach in lieu of opting for default moisture on wet stacksRMB Consulting & research , Environmental Services to IndustryRMB Consulting & research .

7 Environmental Services to IndustryMoisture Determination - Alternative Procedures for Determination of Moisture Content (ALT -091)Unit Run ID Train IDKnockout Initial Weight (g)Knockout Final Weight (g)Knockout Collected Moisture (g)Desiccant Initial Weight (g)Desiccant Final Weight (g)Dessicate Collected Moisture (g)Total Moisture Collected (g)Vwc (std)Vws g (std)Vm (s td)Gravimetric (Bws)Saturation (Bws)Reported Moisture (Bws) 3 Run 4 Method 4 WeightsRun 13 Run 9 Run 10 Run 1 Run 11 Run 5 Run 6 Run 7 Run 4 Potential Mass Emission Calculations Using default moistureHg Concentration (ug/dscm)Hg Concentration (lb/scf)Fc (dscf/mmBtu)Moisture (%)% CO2wE (lb/mmBtu)ET (lb/TBtu)Maximimum Heat Input (TBtu/hr)Maximum Potential Hg Mass Emissions (lb) LEE Qualification - Mass Emission Calculation SummaryHg Concentration (ug/dscm)Hg Concentration (lb/scf)Fc (dscf/mmBtu)Moisture (%)% CO2wE (lb/mmBtu)

8 ET (lb/TBtu)Maximimum Heat Input (TBtu/hr)Maximum Potential Hg Mass Emissions (lb) LEE Qualification - Mass Emission Calculation SummaryRMB Consulting & research , Environmental Services to Industry Potential Mass Emission Calculations Issue with using default moisture valueHg Concentration (ug/dscm)Hg Concentration (lb/scf)Fc (dscf/mmBtu)Moisture (%)% CO2wE (lb/mmBtu)ET (lb/TBtu)Maximimum Heat Input (TBtu/hr)Maximum Potential Hg Mass Emissions (lb) LEE Qualification - Mass Emission Calculation SummaryHg Concentration (ug/dscm)Hg Concentration (lb/scf)Fc (dscf/mmBtu)Moisture (%)% CO2wE (lb/mmBtu)ET (lb/TBtu)Maximimum Heat Input (TBtu/hr)Maximum Potential Hg Mass Emissions (lb) LEE Qualification - Mass Emission Calculation SummaryRMB Consulting & research , Environmental Services to Industry Potential Mass Emission Calculation First determine emission rate with Method 19 (%)ion concentrat CO basis Wet CO(%)

9 Fraction moistureEffluent B)(scf/mmBtuFactor -F basedCarbon F(lb/scf)ion concentratpollutant basisDry C(lb/mmBtu) rateemission Pollutant E:Where%100)1(9-19 Equation 22wwscd2 =wwscdCOBFCERMB Consulting & research , Environmental Services to Industry Potential Mass Emission Calculation Then calculate potential mass emissions Note: if unit has federally enforceable HI or operating hour limits, these values may be used Where: MP Maximum Potential Hg Mass Emissions Per year (lb) ET Pollutant Emission Rate (lb/TBtu) HIMax Maximum Heat Input of Unit (Tbtu/hr) 8760 Maximum Operational Hours per year(hrs) RMB Consulting & research , Environmental Services to Industry Actual Mass Emission CalculationRMB Consulting & research , Environmental Services to IndustryHg LEE Qualification Testing - Emission Rate Results SummaryHg Concentration (ug/dscm)Hg Concentration (lb/scf)Moisture (Bws)Fc (dscf/mmBtu)% CO2wE (lb/mmBtu)

10 ET (lb/TBtu)Spike Recovery (%)Run Potential Hg Mass Emissions per Year (lbs) Consulting & research , Environmental Services to Industry Current Status of Hg Monitoring Operators of Hg CEMS or PS-12B Systems Pa