Passive Diffusion Monitoring

Transcription

1 Passive Diffusion Monitoring for Ammonia in the US U.S. Lear, G. 1, C. Sweet 2,3, M. Caughey 3, C. Lehmann 2,3, T. Dombek 2,3, and D. Gay 2,3 1 U.S. Environmental Protection Agency Clean Air Markets Division 2 National Atmospheric Deposition Program, U of Illinois 3 Illinois i State Water Survey, U of Illinois i NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 1

2 Monitoring Goals Determining the spatial distribution of ammonia concentrations, Determine the seasonality of these concentrations, Help in meeting air quality goals, and improve modeling, CMAQ Ammonia Concentrations, 2001 Provide information for other scientific and policy needs. Cost efficient Network NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 2

3 Goals of This Project Test the Passive Samplers for Performance Develop a cost efficient Network procedures sites Measurement of Ammonia Concentrations NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 3

4 Passive Diffusion Sampler Alternatives Radiello Ogawa I Alpha E F C All vs. Denuders ( standard method ) NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 4

5 Radiello NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 5

6 Results of the Diffusive Samplers Blanks Accuracy Laboratory Blanks Travel Blanks vs. denuderd Repeatability Ti Triplicate samples Reporting limit NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 6

7 Radiello Ammonium Lab Blanks With Time mg g/liter Median Lab Blank= mg/l ph Imbalance w/instrument Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Dist. Water Oct-08 Lab Blank NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 7

8 Radiello Ammonium Travel Blanks With Time Contaminated valid travel blanks Shipping Containers mg/liter Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 8

9 Radiello Accuracy Radiello vs Denuder Ammonia Concentrations ppb Ammon nia Oct-07 Nov-07 Dec-07 Jan-08 Feb-08 Mar-08 Apr-08 May-08 Jun-08 Jul-08 Aug-08 Sep-08 IL11 Con IL11 Avg Oct-08 Denud NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 9

10 Alpha Accuracy Accuracy: Alpha vs. Denuder Ammonia Con. ppb Ammonia Feb-08 Mar-08 Apr-08 May-08 Jun-08 Jul-08 Aug-08 Alpha Alpha Avg Sep-08 Denud NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 10

11 Ogawa Accuracy Accuracy: Ogawa vs Denuder Concentrations 10 ppb Am mmonia Oct-07 Nov-07 Dec-07 Jan-08 Feb-08 Mar-08 Apr-08 May-08 Jun-08 Oga Con Oga Avg Jul-08 Denud NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 11

12 Repeatability of Passives Repeatability: Difference From the Mean ppbv Diff ference Rad ddiff Oga Diff Alpha Diff Sep-07 Nov-07 Jan-08 Feb-08 Apr-08 Jun-08 Jul-08 Sep-08 Oct-08 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 12

13 Repeatability Comparison Comparisons ppbv units Measure Radiello Alpha Ap Ogawa a Repeatability Removed From consideration median difference (vs avg) maximum difference (vs avg) Standard Dev. Of difference th perc. Difference th perc. Difference interquartile range n NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 13

14 Radiello x Alpha Accuracy Radiello vs Denuder Ammonia Concentrations Alpha Denud IL11 ppb Amm monia Feb-08 Mar-08 Apr-08 May-08 Jun-08 Jul-08 Aug-08 Sep-08 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 14

15 Radiello x Alpha, Cost Comparisons Costs Measure Radiello Alpha Costs Body ($) $8.00 $23.00 no. of body uses Replaceable "core"/filter ($) $ replaceable membrane $ year, triplicate samples $874 $60 cleaning (hrs) minimal minimal preperation little somewhat more Alphas are English ( to $ conversion) NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 15

16 Radiello vs. Alpha Travel Blanks Radiello and Alpha Travel IL Radiello TB Alpha TB mg/lite er Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 16

17 Low Bias for Passive Diffusion Samplers Consistently below the denuders Average Median ppbv ppbv % Abs % Denuder Radiello Alpha Radiello - Den Difference % 37% Alpha - Den Difference % 35% March to Sept 2008 measurements only Denuders flow checks to two separate mass flow devices Lab blanks and travel blanks are clean 2 sequential denuders; no breakthrough to 2 nd denuder Agree with monitor (Nitrolux 200) Radiellos & Alphas Generally agree Limited observations, particularly for winter NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 17

18 Radiello Method Detection Limit With a two-weekweek sample, Average lab blank of mg/l Standard ddeviation i of mg/l, and Method Detection Limit = (L blank +2 std) Method Detection Limit of 0.15 ppbv NH 3 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 18

19 Summary Ogawa No longer being considered d High variation within triplicates (wind orientation likely) Radiello Generally good agreement with denuders Relatively low bias Low variation between replicates Good blanks Expensive Alpha Blanks seem to be as good as Radiello Generally good agreement with denuders Relatively low bias Low variation between replicates LOW cost Considering for adoptions NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 19

20 Ammonia Monitoring Network (AMoN) 21 Sites operating (as of Sep 2008) Two-week samples in triplicate Radiello Sampler Sampling began Oct 30, triplicate icate measurements e e (9/2/08) /08) NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 20

21 Network Sites NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 21

22 Measurement Results General stats Max, min, etc overall sites Time lines by site or state or region Median, range max min weekly standev about mean, n= NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 22

23 Concentrations: New York 67 (Connecticut Hill) Ammonia (p ppb) likely contamination below reporting limit NY67 Sep-07 Nov-07 Jan-08 Feb-08 Apr-08 Jun-08 Jul-08 Sep-08 Median Perc th Perc Maximum 1.66 Minimum 0.03 Average 0.50 St. Deviation 0.44 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 23

24 Concentrations: Kansas 24 (Coffeeville) Ammonia (ppb) likely contamination Sep-07 Nov-07 Jan-08 Feb-08 Apr-08 Jun-08 Jul-08 Sep-08 Median Perc th Perc 2.24 Maximum Minimum 1.57 Average St. Deviation 3.98 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 24

25 Concentrations: Illinois 11 (Bondville) Ammonia (p ppb) possible contamination Sep-07 Nov-07 Jan-08 Feb-08 Apr-08 Jun-08 Jul-08 Sep-08 Oct-08 Median Perc th Perc 0.19 Maximum 8.19 Minimum 0.00 Average 1.74 St. Deviation 1.84 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 25

26 Fall Concentrations November 2007 Concentrations Gaseous Ammonia ppb pp NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 26 >10.0

27 Fall Concentrations November 2007 Concentrations Gaseous Ammonia ppb >10.0 Precip. Ammonium /L mg/l NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide >0.65

28 Winter Concentrations December 2007 February 2008 Concentrations Gaseous Ammonia ppb pp NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 28 >10.0

29 Winter Concentrations December 2007 February 2008 Concentrations Gaseous Ammonia ppb >10.0 Precip. Ammonium /L mg/l NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide >0.65

30 Spring Concentrations March 2008 May 2008 Concentrations Gaseous Ammonia ppb pp NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 30 >10.0

31 Spring Concentrations March 2008 May 2008 Concentrations Gaseous Ammonia ppb >10.0 Precip. Ammonium /L mg/l NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide >0.65

32 Next Steps Funding through October 2009 Seek additional sponsors Reduce costs of Radiellos Determine optimum number of replicates Decision on elimination by January 2009 Field blank corrections Still too much contamination Goal: 0.2 ppbv correction (limit) Prep, removal, analysis all in one hood New glass shipping tubes (into ISWS next week) NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 32

33 Next Steps Additional denuder comparisons NC sites Environment Canada a a Additional alphas at CO and TX sites Make preliminary data available by January 2009 Meeting of interested parties Thursday afternoon NADP Spring 2009 NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 33

34 Acknowledgements Additional financial support from the Lake Michigan Air Directors Consortium (LADCO), Chicago IL NADP Fall Meeting 2008, Madison WI, Oct 14-16, 2008, Slide 34