Accurate Benzene, Toluene, Ethyl-Benzene and Xylene (BTEX) Measurements at Low ppb Levels in Real Time
There has always been a diffi culty in accurately quantifying benzene in air. Until recently, the only viable method of specifi cally measuring benzene at environmental levels (10 – 50 ppb) was through the use of grab samples and GC/MS. The DV3000 UV Gas Analyser from Duvas Technologies has the ability to accurately analyse a wide range of gases, including BTEX gases, simultaneously to ppl levels without cross-interference between species.
The DV3000 uses closed path spectroscopy and a DOAS-based technique to feed emission data to an advanced algorithm. Each species corresponds to a unique absorption spectrum; the algorithm is able to match the species via this ‘fingerprint’ allowing for detection and differentiation between species in complex mixtures. The DV3000 design performs analyses in a stationary and mobile mode. Using high performance Lithium battery packs, field surveys can be performed for up to six hours. These packs can easily be hot-swapped during analysis for uninterrupted operation and prolonged field deployment. The HEPA filter and mesh system prevents mirror contamination from particles greater than 0.8 microns. A Bluetooth and GPS option enables data to be streamed in real time onto an Android tablet.
Figure 2: Benzene levels from Duvas gas test at areas surrounding Immingham chemical plants, Aug 2016
Figure 1: Benzene levels from Duvas gas test at areas surrounding Immingham chemical plants, Aug 2016
In the examples shown, a DV3000 instrument was used to perform a survey of public roads around two chemical plants in Immingham in the UK in August 2016. The instrument was mounted in an automobile and driven around the plants where it was Bluetooth and GPS enabled, allowing for results to be viewed in real time on an Android tablet during the analysis of the areas. Additionally, this feature allows for data to be pinpointed to an exact location during the reprocessing of data at a later time. The highest benzene levels were close to 100 ug/m3 or approximately 30 ppb, while ethylbenzene levels peaked to 225 ug/m3, approximately 50 ppb.
Author Contact Details Dr Julian Iredale, CTO, Duvas Technologies Ltd. • Email:
j.iredale@
duvastechnologies.com • Web:
www.duvastechnologies.com
IET March / April 2017
www.envirotech-online.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84
