Total Hydrocarbon Monitoring at the Agent Filtration Area (AFA) at PCAPP Using Photoacoustic Spectrometers

Transcription

1 Total Hydrocarbon Monitoring at the Agent Filtration Area (AFA) at PCAPP Using Photoacoustic Spectrometers Dr. Gary D. Sides and Mr. Walter L. Waybright

2 Acronyms ACFM Actual Cubic Feet per Minute AFA Agent Filtration Area ANR Agent Neutralization Reactor (hydrolyzer) APB Agent Processing Building CDPHE Colorado Department of Public Health COPC Chemical of Potential Concern and Environment DCA 1,2-Dichloroethane ERB Enhanced Reconfiguration Building HAL High Agent Loading (test) HD Agent mustard HEPA High Efficiency Particulate Air (filter) HVAC Heating, Ventilation, and Air Conditioning (system) IDLH Immediately Dangerous to Life and Health MINICAMS Miniature Automatic Continuous Air Monitoring System MPHRA Multiple Pathway Health Risk Assessment MTU Munitions Treatment Unit MWS Munitions Washout System OTS Off-Gas Treatment System PAS Photoacoustic Spectrometer PCAPP Pueblo Chemical Agent-Destruction Pilot Plant ppm parts per million (by volume) PTD Pilot Test Demonstration SDU Supplemental Decontamination Unit THC Total Hydrocarbon VC Vinyl Chloride VOC Volatile Organic Chemical 2

3 Off-Gassing from Various Systems Vent to the Off-Gas Treatment System (OTS) Systems in Agent Processing Building (APB) venting to OTS Munitions washout systems MWS wash water tanks Agent/water separators Agent hydrolyzers (reactors) Agent hydrolysate hold tanks Munitions Treatment Units (MTUs) Supplemental Decontamination Unit (SDU) Autoclave 3

4 Exhaust from OTS and HVAC Air from the APB Pass Through Carbon Filters Agent Filtration Area (AFA) Enhanced Reconfiguration Building (45,3 ACFM) Agent Processing Building (APB) (78,7 ACFM) ERB Exhaust APB Exhaust MK-M7-1 MK-M7-11 MK-M7-12 APB Exhaust includes MK-M7-13 Exhaust gas from the OTS HVAC air contaminated due to Waste handling activities Decontamination activities Leaking seals Champagning rounds Etc. MK-M7-14 MK-M7-15 MK-M7-16 Eight (8) of ten (1) carbon filter units on-line at all times; Filters 7, 8 and 9 not shown. 4

5 Pre-Operational PCAPP Multiple Pathway Health Risk Assessment Pre-operational chemical emissions estimate completed for PCAPP An MPHRA, a screening-level assessment of potential risk of PCAPP operations on human health, was then completed MPHRA results indicated that 1,2-dichloroethane (DCA) and vinyl chloride (VC) are the non-agent chemicals with the primary impact on potential health risks Pre-operational emissions estimates for DCA and VC at the AFA stack were 4.8 and 5. lb/day, respectively Estimated concentrations for DCA and VC at the AFA stack were much less than the calculated DCA and VC MPHRA thresholds for a one-in-a-million cancer risk Chemical Emissions, lb/day Est. Stack Concn, ppm MPHRA Threshold, ppm Pre-Operational Estimates: 1,2-Dichloroethane Vinyl chloride

6 Sampling at the Agent Filtration MK-M7-1Area ERB Exhaust During the Pilot Test Demonstration APB Exhaust Enhanced Reconfiguration Building (45,3 ACFM) Agent Processing Building (78,7 ACFM) MK-M7-11 MK-M7-12 ERB Exhaust MK-M7-13 APB Exhaust MK-M7-14 MK-M7-15 Sampling of concern for the study described in this presentation MK-M7-16 MK-M7-1 MK-M7-11 MK-M7-12 MK-M7-13 MK-M7-14 Total Hydrocarbon (THC) Analyzers THC Monitoring performed on two on-line AFUs (11 through 16) continuously (LSAP CLA#8 and CLA#9b sampling at stack and at three on-line AFUs (11 through 16) during each OTS/AFA COPCs (Summa canisters, TO-15) test activity (PTDP Appendix A6; LSAP CLA#8 and CLA#12) Carbon sampling at Bank 3 and potentially Bank 6 (see DQO) of all AFUs performed minimum of four Carbon times during Sampling pilot testing immediately following COPC sampling (Carbon Sampling Strategy; LSAP CLA #11) (butane working capacity) MK-M7-15 MK-M7-16 1,2-DCA (VOC) and Hg sampling on 8 on-line AFUs performed during each OTS/AFA test activity (PTDP Appendix A6, LSAP CLA #1) Eight (8) of ten (1) carbon filter units on-line at all times; filters 7, 8 and 9 not shown. General emissions sampling (particulates, sulfur/nitrogen oxides, acid gases, metals, dioxins/ furans) performed at stack (PTDP Appendix A6, LSAP CLA#12 6

7 Total Hydrocarbon Monitoring During the Pilot Test Demonstration (PTD) Required by the Colorado Department of Public Health and Environment (CDPHE) Real-time THC monitoring intended to supplement manual sampling for Chemicals of Potential Concern (COPCs) at the Agent Filtration Area Goals for THC monitoring during the PTD: Determine whether real-time THC data correlate with COPC sampling data obtained during routine operations and, thus, may be used as a real-time indicator of process emissions (from systems in the APB) correlate with COPC sampling data obtained during process upset conditions and, thus, may be used as a real-time indicator of upset conditions correlate with butane working capacity for AFA carbon and, thus, may be used as an indicator of remaining carbon activity Reference: PCAPP Position Paper on Total Hydrocarbon Monitoring During Pilot Test Demonstration, H--V3, Rev. 1 7

8 Total Hydrocarbon Monitoring During the Pilot Test Demonstration Photoacoustic Spectrometer (PAS) Advertised lower detection limits than for conventional flame-ionization-based THC analyzers Continuously monitor for vinyl chloride (VC) and 1,2-dichloroethane (DCA)* Continuously monitor for total hydrocarbons (THC, reported as propane; not including VC) Reported concentrations compensated for interferences from water vapor (H 2 O), carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) INNOVA Model 1412i (LumaSense Technologies, Inc.) *DCA and VC were expected to constitute 95% of non-hd VOC emissions from systems in the Agent Processing Building. DCA and VC averaged 97% of non-hd VOCs in 2 HEPA/Bank 1 Summa canister samples collected during 1 different PTD tests. 8

9 Operation of the THC Analyzer (PAS) Based on the measurement of infrared (IR) absorption Reports THC, VC and DCA concentrations once every 5 min compensated for interferences from H 2 O, CO 2 and N 2 O 9

10 Pre-Operational Performance of the THC Analyzers 7/22-8/23/16 Baseline Baseline total hydrocarbon (THC), carbon dioxide (CO 2 ), and nitrous oxide (N 2 O) concentrations reported were in agreement with known atmospheric levels of methane (CH 4 ), CO 2 and N 2 O THC concentrations (reported as propane) pooled mean for 4 analyzers:.37 ppm analyzers 5X less sensitive to methane than to other hydrocarbons 5 x.37 ppm = 1.85 ppm, near atmospheric levels of methane pooled standard deviation for 4 analyzers:.54 ppm baseline mean plus 3 standard deviations:.53 ppm ( control limit ) CO 2 concentrations (baseline lowest levels) about 42 ppm, near atmospheric levels N 2 O concentrations (baseline lowest levels) about.34 ppm, near atmospheric levels 1

11 Concentration, ppm H2O Concentration, ppm Pre-Operational Performance of the THC Analyzers 7/22-8/23/16 Baseline Water vapor (H 2 O) concentrations (black trace) in the range of 1, to 3, ppm (about 3 to 95% RH at 25 C) Frequent fluctuations in H 2 O concentrations (black trace) correlated with small fluctuations in reported THC concentrations (blue trace) periodic false positives for reported DCA concentrations (orange trace) no false positives for reported VC concentrations (red trace) but negative baseline /6/16 8/7/16 8/8/16 VC THC DCA H2O 11

12 Typical Concentrations Reported During Suspended Operations 11/21/16 1/12/17 H 2 O concentrations about 5,-9, ppm (low humidity compared to baseline period) No high-frequency fluctuations in reported H 2 O concentrations No H 2 O-correlated false positives for DCA VC baseline at about. ppm 12

13 Typical Data Reported During Munitions Processing (VC) 13

14 Typical Data Reported During Munitions Processing (THC, DCA, H 2 O) Typically, minor changes in THC concentrations No indication of DCA emissions Does not include VC Low humidity from mid-sept 216 to about April

15 Concentration, ppm Munitions Count Concentration, ppm Munitions Count Example of THC Analyzer Data During Munitions Processing (HEPA/Bank 1) Correlation of munitions processing with reported VC concentrations 3 VC HP Wash Water Daily Munitions Count /12/216 11/13/216 11/14/216 11/15/216 11/16/216 11/17/216 11/18/216 11/19/216 Correlation of munitions processing with reported THC concentrations*.5 HP Wash Water THC Daily Munitions Count /12/216 11/13/216 11/14/216 11/15/216 11/16/216 11/17/216 11/18/216 11/19/216 *Reported THC concentrations do not include VC 15

16 Comparison of THC Analyzer Data and Summa Canister Results (HEPA/Bank 1) Obtained during Pilot Test Demonstration tests (5-hr sample periods) Dilution factor for COPC (Summa canister) samples typically > 1X Date Pilot Test Demonstration (PTD) Test Filter Summa DCA, ppb Summa VC, ppb Analyzer VC, ppb 1/18/16 MWS/MTU Demonstration Test /1/16 ANR Demonstration Test /8/16 ANR Demonstration Test /15/16 MWS/MTU Demonstration Test 2 11 * * /16/16 OTS/AFA Demonstration Test *Not shipped for analysis due to quality failure in the agent screening analysis 16

17 Comparison of THC Analyzer Data and Summa Canister Results (HEPA/Bank 1) Tests highlighted in red: simulated process upset conditions High Agent Loading (HAL) Demonstration Test 2: one of the two ANR batches processed during the test had 23% agent by weight versus target of 15% Date Pilot Test Demonstration (PTD) Test Filter Summa DCA, ppb Summa VC, ppb Analyzer VC, ppb 1/31/17 OTS/AFA Demonstration Test /7/17 MTU Heel Demonstration Test /26/17 HAL Demonstration Test ND* ND* 763 3/8/17 OTS/AFA Demonstration Test /9/17 HAL Demonstration Test *Reason for non-detects is unknown. 17

18 Analyzer VC, ppmv VC, ppm H2O, ppm Validation of the Performance of the THC Analyzer for Vinyl Chloride (VC) Comparison to COPC (Summa canister) samples for VC (HEPA/Bank 1) average VC concentration over 1 different 5-hr test periods good correlation, but THC Analyzer results average 4% higher R 2 =.88 for all VC data; R 2 =.84 for VC process upset data (red) VC challenges (2 ppm) in dry and humid air reported concentrations within about + 1% of target for up to 9, ppm H 2 O Correlation with COPC Data (Filters 11 and 16) Dry/Humid/Dry VC Challenges R² = H2O VC Summa Canister VC, ppmv

19 DCA, ppm H2O, ppm Performance of the THC Analyzer for 1,2-Dichloroethane (DCA) DCA concentrations reported by the THC analyzers are unreliable. Dry/Humid/Dry DCA Challenges 4 H2O DCA False positives for DCA when water vapor concentrations greater than about 1, ppm and fluctuating DCA response suppressed by water vapor Means for drying the THC Analyzer sample stream in real-time are available DCA concentrations for wet Summa canister samples typically ppb Estimated detection limit for DCA for the THC analyzers: 6 ppb (in dry air) Appears to be of little consequence due DCA emissions << MPHRA threshold value 19

20 THC Analyzers as Indicators of Process Upset Conditions Numerous sensors/transducers in the Agent Processing Building provide data indicative of process upset conditions e.g., flow rates, pressures, temperatures, liquid levels, etc. Operators in the Control Room also monitor processes via CCTV e.g., to detect liquid leaks and spills due to failed seals, champagning rounds, etc. MINICAMS units detect process upset conditions that result in significant airborne concentrations of agent HD even if no sensor/transducer signal being monitored indicates an upset condition THC analyzers have the potential to detect, in real time, process upset conditions that result in significant increases in THC and VC process emissions* from systems in the APB even if no sensor/transducer signal being monitored indicates an upset condition *THC and/or VC process emissions beyond established control limits may be defined as process upsets even if the underlying causes are not immediately apparent. 2

21 THC Data as a Supplement to Other Sensors in Detecting Process Upset Conditions Based on review of THC Analyzer data to date, process upset conditions for HEPA/Bank 1 locations may exist if Hourly average vinyl chloride > MPHRA threshold (1.47 ppm) and/or 5-min THC concentration > baseline control limit (.53 ppm) Hourly average vinyl chloride concentrations > 1.47 ppm 11 instances during 6 months of munitions processing 6 of the 11 instances during identifiable off-normal (upset) conditions 5-min THC concentrations (not including VC) >.53 ppm 22 instances during 6 months of munitions processing 6 of the 22 instances during identifiable off-normal (upset) conditions Hourly average VC > 1.47 ppm and 5-min THC >.53 ppm 9 instances during 6 months of munitions processing 5 of the 9 instances during identifiable off-normal (upset) conditions 21

22 Butane Working Capacity, % Bank 3 Carbon Efficiency Butane Working Capacity Filter 11 ASTM D5228 Standard Test Method for Determination of Butane Working Capacity of Activated Carbon 7/5/216 8/24/216 1/13/216 12/2/216 1/21/217 3/12/217 Filter 7 Filter 8 Filter 9 Filter 1 Filter 11 Filter 12 Filter 13 Filter 14 Filter 15 Filter 16 1/25/16 11/17/16 3/14/17 22

23 Examples of THC Filtration at Filter 16 THCs (HD) filtered effectively by carbon beds C1-C3 (4/29/17) THCs (non-hd) not filtered by carbon beds C1-C3 (2/1/17) HD MINICAMS (IDLH) MWS Rooms 1 & 2 HD MINICAMS (IDLH) MWS Rooms 1 & 2 23

24 Concentration, ppm Munitions Count Summary VC concentrations reported by photoacoustic-based THC analyzers at PCAPP correlate with munitions processing VC concentrations reported by THC analyzers correlate with COPC sampling data during normal and upset conditions and, thus, may be used as an indicator of process emissions Increases in reported THC and VC concentrations (beyond defined control limits) may be indicative of process upset conditions VC concentration data during munitions processing may be indicative of remaining carbon activity additional carbon efficiency data needed 3 VC HP Wash Water Daily Munitions Count /12/216 11/13/216 11/14/216 11/15/216 11/16/216 11/17/216 11/18/216 11/19/216 24