United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/S7-86/025 Sept. 1986
Project Summary
Recovery of Principal Organic
Hazardous Constituents and
Products of Incomplete
Combustion from a Volatile
Organic Sampling Train
Esther V. Robb, James F. McGaughey, Alston L Sykes, and
Denny E. Wagoner
This report describes an investigation
of the recovery efficiencies of selected
principal organic hazardous con-
stituents (POHCs) from the Volatile Or-
ganic Sampling Train (VOST) under lab-
oratory conditions. Analytical
procedures discussed in the text in-
clude preparation of the standard solu-
tion, resin, and sampling traps; sample
generation; sampling; analysis; and
quality asssurance. Calibration devel-
opment and treatment, as well as anal-
ysis validation, are discussed in detail.
The discussion of the results includes
the POHCs recovery efficiencies and
POHC distribution through a set of sam-
pling traps. Additionally, detailed preci-
sion and accuracy estimates are pre-
sented.
This Project Summary was devel-
oped by EPA's Air and Energy Engineer-
ing Research Laboratory, Research Tri-
angle Park, NC, to announce key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report
ordering information at back).
The Report
The Resource Conservation and Re-
covery Act of 1976 requires that owners
and operators of facilities which treat
hazardous waste by incineration ensure
that the incinerators are operated in an
environmentally responsible manner.
Such incinerators are required to have a
destruction and removal efficiency
(ORE) of 99.99% for each POHC desig-
nated in the Trial Burn Permit. The ORE
standard, thus, requires that the POHCs
be quantified by the sampling and anal-
ysis of the waste feed material and the
stack gas effluent. Methods commonly
used for the collection and analysis of
volatile organics are the VOST followed
by thermal desorption and GC analysis
of the VOST traps. Any such methods
used in the evaluation of the incinera-
tor's DRE should be evaluated and
shown to provide accurate and precise
data for each POHC designated in the
Trial Burn Permit.
To ensure that the above mentioned
methods provide accurate DRE data, the
recovery efficiencies of selected POHCs
from the VOST were investigated in this
work. The compounds included vinyl
chloride, carbon tetrachloride,
trichloroethylene, benzene, toluene,
perchloroethylene, monochloroben-
zene, methyl vinyl ketone, tetrahydro-
furan, and chloroform. To determine
the compound recoveries, a VOST train
and an in-house organic vapor genera-
tion system were used. The generation
system, shown in Figure 1, was used to
produce known steady state levels of
the chosen POHCs. The vaporized and
gaseous POHCs were collected by the
VOST, shown in Figure 2, and concen-
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A ^ MI Cylinders
Carrier Gas Flow Control
^•>.
C) Dilution Gas Flow Control
*w^
(Dj Constant Temperature Bath
Moisture Vessel
F) Air Heater
G Volatilizing Chamber
H) Motorized Syringe
(/) Constant Temp Chamber
(J) Carrier Gas Heater
'J<) Gtess Mixing Bulb
(T) Dilution Gas Heater
(M) Constant Temp Chamber
vj Glass Sample Manifold
PORT = Charcoal Cell
PORT = Moisture Train
PORT= VOST
(ft) PORT= VOST
? Exhaust
Thermocouple Location
Figure 1. Organic vapor generation system.
trated in the polymeric resin, Tenax®.
Inside/Inside (I/I) VOST sampling traps
were used for sampling analyses. Three
traps were used in tandem for all sam-
pling: Tenax® (1.6 g), Tenax® (1.0 g),
and charcoal (1.0g). The traps were
then separately thermally desorbed and
analyzed using GC/FID and GC/MS
detection.
Four-point calibration curves were
initially developed using the VOST
traps. All response curves were devel-
oped by linear regression, except in the
event of a non-linear response. Control
samples, treated identically to the VOST
samples, were used as a check on the
instrument calibration. Each sample
and standard trap were spiked with a
known amount of the internal standard,
bromofluorobenzene (BFB), prior to
analysis. BFB was then used not only to
provide an analysis system check, but
also to validate the analyses. The BFB
analysis validation limit was ±3 of the
overall mean BFB response value.
To determine the recovery efficien-
cies, the expected- total nanograms of
POHCs were compared to the total
nanograms found by the GC/FID analy-
sis. Excluding vinyl chloride and methyl
vinyl ketone, the overall mean percent
recovery for the individual compounds
ranged from 81.03% for tetrahydrofuran
to 118.1% for chloroform. Vinyl chloride
had an overall mean percent recovery of
55.23%, most likely since thermal de-
sorption does not tend to drive off vinyl
chloride from activated charcoal as ef-
fectively as other organics from
Tenax®. Methyl vinyl ketone also had a
poor overall mean percent recovery of
37.82%, which was likely due to an ap-
parent degradation of methyl vinyl ke-
tone in the POHCs solution.
The mean percentage breakthrough
of compound past the first sampling
trap into the second or third trap for all
compounds, except vinyl chloride, was
found to be less than 5%. Individually,
the overall mean percentage break-
through of each compound ranged
from 0.0 to 9.6%, except for vinyl chlo-
ride which had a constant breakthrough
of 100% past Tenax® onto the activated
charcoal.
The precision was found by pooling
the coefficients of variation for all the
compounds in the daily calibration
checks or control standards. The accu-
racy was found by comparing the ex-
cepted amounts of PO,HCs in the gener-
ation system to those found by GC/FID
analysis. The precision for the POHCs,
including all compounds, was found to
be 15.871%. Excluding methyl vinyl ke-
tone and vinyl chloride, the overal
mean percent accuracy for each com
pound ranged from -18.97% for tetra
hydrofuran to +18,08% for chloroform
Vinyl chloride had an overall mean ac
curacy of -44.76%, while methyl viny
ketone had an overall mean accuracy o
-62.18%, for which the likely causes an
mentioned above.
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Glass Sample
Manifold
Port
Probe
Heat
3 Calibrated
Rotometer
5
\) Pressu
if Gauge
T-,
Tt
T3
T,
To
T»
re
— in. 1
f em p. nett
Stack
Probe Exit
Entrance to
Entrance to
Meter In
Meter Out
Y20
JUUl I
Temak 1
Temak 2
Sample,
Line
Vacuum
Gauge
Main
Valve
Electrical
Line
Bypass
Valve
rCH
O
Dry Gas Meter
1 LPR Calibrated
I \
Lock Free
Pump
Figure 2. Schematic of the VOST and control module.
£. V. Robb, J. F. McGaughey. A. L Sykes, andD. £. Wagoner are with Radian Corp.,
Research Triangle Park, NC 27709.
Robin Anderson is the EPA Project Officer (see below).
The complete report, entitled "Recovery of Principal Organic Hazardous
Constituents and Products of Incomplete Combusion from a Volatile Organic
Sampling Train," (Order No. PB 86-219 003/AS; Cost: $11.95, subject to
change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield. V'A 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S7-86/025
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