Rearden_GCC_2015

1st Detect Proprietary www.1stdetect.com

Preshious Rearden, Ph.D.

Senior Applications Chemist

[email protected] GCC - October 20, 2015


Air Toxic Monitoring

US EPA Requires Oil Refineries To Monitor Benzene Levels

Other Hazardous Air Pollutants (HAP) include 1,3-butadiene, toluene, ethylbenzene,

and xylenes

Method 325 established by the EPA for fenceline monitoring of benzene at petroleum

refineries

• Method sets standards for sampler placement, sample collection, preparation, and

analysis

• Recommends a passive sampling approach

‒ 12 to 24 passive samplers placed at 15 to 30 degree intervals along the perimeter

of each refinery

‒ Sampling cycle: 14 days


Passive Sampling - Limitations and Challenges

Passive Sampling

Samples analyzed off-line

Inability to identify emission source

Miniature Mass Spectrometer As An Alternative

Approach To Passive Sampling


iONTRAC

Why iONTRAC?

Program and monitor gas streams in real-time

Data from unused channels stored for future analysis

No carrier gases required

Operator controlled or autonomous unattended operation

Continuous monitoring

Out-of-spec product alarms

Cost Effective

Miniature ion trap mass spectrometer

Mass Range: 35 – 500 amu

Dynamic Range: 2 orders of magnitude

Gases Monitored: User programmable (up to 8 ions)


GOAL

To Demonstrate the Feasibility of the iONTRAC to Monitor HAPs

Monitor benzene and ethylbenzene excursions

Evaluate the iONTRAC’s performance under ambient conditions


Ambient Monitoring Technical Approach

iONTRAC equipped with a preconcentrator utilizing a Carbopack X sorbent

• Sampling Time: 70 s

• Desorption Time: 60 s

Instrument was placed in parking lot at 1st Detect’s facility in Webster TX

System challenged with benzene and ethylbenzene at varying distances

Mixtures of benzene and ethylbenzene analyzed

Meteorological data recorded with each simulated emission

Sampling Mode: Continuous

Sample period: 5 days

• Hold Time: 200 s

• Desorption Temp: 300C


Experimental Set-up

iONTRAC

Weather Station

180 ft

Excursion


Baseline Recovery

Benzene

Ethylbenzene

Removed Sample 180 ft Excursion

m/z = 78

m/z = 91 m/z = 106

In

te

nsity (a

.u

.)

In

te

nsity (a

.u

.)


Reproducibility

Added Benzene Benzene In

te

nsity (a

.u

.)


Meteorological Effects

Wind Speed and Direction

3 m

ph

WN

W

3 m

ph

N

3 m

ph

S

3 m

ph

EN

E

3 m

ph

E

iONTRAC

Sample

Benzene Toward iONTRAC

Away from iONTRAC

In

te

nsity (a

.u

.)


VOC Detection

Benzene and Ethylbenzene

Benzene (m/z = 78)

Ethylbezene (m/z = 91)

Ethylbezene (m/z= 106)

100 ft

Inte

nsit

y (

a.u

.)


Detection Levels

Benzene

Benzene and Ethylbenzene Detected at 200 ft

20 ft

Intensity as a Function of Distance

In

te

nsity (a

.u

.)

A

vg. Inte

nsity (a.u.)

In

te

nsity (a

.u

.) 200 ft


Summary

iONTRAC offers continuous real-time monitoring of VOCs in

ambient air with:

• Rapid clear down rates (< 2 min)

• Stable and rapid response time

• Detection VOCs levels to a least 200 ft

• Simultaneous monitoring of multiple VOCs

• Faster detection times than passive sampling (<5 min)


Future Directions

Optimize sampling and detection time

Test additional compounds

Increase the number of sampling ports on the iONTRAC

Test units on-site at petroleum refineries

Where Do We Go From Here?


Acknowledgements

Corey Stedwell, Ph.D.

Daniel DeBord, Ph.D.

Madonna Mamerow, Ph.D.

Parminder Kaur, Ph.D.

James Wylde, Ph.D.

David Rafferty


Thank You!


Questions?

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