John Birks, Peter Andersen, Craig Williford and Andrew Turnipseed

24 Pages·2015·1.62 MB·English

2B Tech Model 211 Scrubberless Ozone Monitor

for Interference-Free Measurements
John Birks, Peter Andersen, Craig Williford & Andrew Turnipseed
2B
Technologies, Inc.
FEM/FRM Ozone Monitors in
Monitoring Network
 Ethylene Chemiluminescence (FRM, 0%)

 UV Absorbance (FEM, >99%)
• Teledyne API 400 series
• Thermo-Fisher 49 series
• Dasibi 1003/1008
• 2B Technologies 202, 205

 NO + O Chemiluminescence (FEM, New FRM)
3
• Teledyne API Model T265

 Scrubberless UV Absorbance (FEM, Candidate FRM)
• 2B Technologies Model 211
Problem: Many Atmospheric Species Absorb at 254 nm
e.g., Hg, Aromatics, Aldehydes & Ketones, Nitro Compounds
Hg Line at 253.7 nm
Example: Toluene
Absorbs ~26 x less strongly than ozone at 253.7 nm
9
3
1
1.2 .
1
0
0
0
.
1
1
Absorbance Relative to Ozone
0.8

8
1
0.6 5
.
0
0.4 8
5
2
.
0
4
3 5
1 3 2
0.2 1 3 6 73 32 83 .0 90. 1.0 5
0 1 0 0 0 0 0 1
0 0 0 . . . 0
.0 .0 .0 0 0 0 .0
0
Response to p-Xylene using Different Ozone Scrubbers
Relative Response to Mercury using Different Ozone Scrubbers
Comparison of UV (FEM) with Ethylene CL (FRM)
Ozone Measurements in Mexico City
30 ppb 8-hr Averages
April 28, 1998
Azcapotzalco
Mexico City

UV: Thermo 49
CL: Bendix 8410
Alan R. Leston, Will M. Ollison, Chester W. Spicer and Jan Satola, “Potential
Interference Bias in Ozone Monitoring” (2005) Air and Waste Management
Association 55, 1464-1472.
Conventional Ozone Monitor
Scrubberless Ozone Monitor
Schematic Diagram of Model 211 Ozone Monitor