United States
Environmental Protection
Agency
Industrial Environmental
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA-600/S2-84-089 July 1984
Project Summary
Controlled Air Incineration of
Pentachlorophenol-Treated Wood
L.A. Stretz and J. S. Vavruska
A research test program was con-
ducted to investigate the destruction of
pentachlorophenol-(PCP) treated wood
in a controlled air incinerator. PCP-
treated wood is frequently used in the
manufacture of United States military
ammunition boxes. The disposal of
used boxes is a problem of considerable
concern to the U.S. Department of
Defense at military installations in the
United States and, in particular, Korea.
The results of test burns indicated that
destruction efficiencies (DE) for PCP
sampled in the hot zone transfer duct
from the controlled air chamber leading
to the high temperature afterburner
were greater than U.S. Environmental
Protection Agency stack emission
standards in all tests. This research
program was conducted in cooperation
with and with partial funding from the
U.S. Department of Defense, Defense
Property Disposal Service, under Inter-
agency Agreement AR-21-F-1-741-0.
This Project Summary was developed
by EPA's Industrial Environmental
Research Laboratory, Cincinnati. OH.
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).
Introduction
Incineration of pentachlorophenol-
(PCP-) treated wood under inadequate
combustion conditions or in open burning
has shown to generate toxic products of
incomplete combustion (PICs). Various
chlorinated organic species can occur as
combustion products from burning PCP-
treated wood such as the chlorinated
dibenzodioxins and the chlorinated
dibenzof uran. The controlled air incinera-
tor (CAI) used in this study was capable of
incinerating the PCP-treated wood effec-
tively while avoiding production of PICs.
The disposal of wood treated with PCP
has become a significant problem for the
U.S. Department of Defense (DOD),
particularly in the Republic of Korea
(ROK). Wooden ammunition crates are
treated with PCP to prevent decomposition
of wood due to termite or other insect/
borer infestation during transportation and
storage. Disposal of the empty crates by
sale or burial is prohibited in Korea. The
volume of wood is so large that shipment
back to the United States is impractical.
Incineration of the crates in the ROK is
believed to be the most cost-effective
option.
The ROK asked for evidence to support
the case for incineration of these materials
and to present data showing that inciner-
ation creates an additional problem.
DOD, through the Defense Property
Disposal Service (DPDS) partially supported
an Interagency Agreement the EPA
implemented with the Department of
Energy (DOE) to conduct research using
the CAI located at Los Alamos National
Laboratory in Los Alamos, New Mexico.
Thus, the EPA, DOD, and DOE all
collaborated on this study for the safe
incineration of PCP-treated wood.
Process Description
The basis of the Los Alamos CAI is an
Environmental Control Products (Charlotte,
North Carolina) model 500-T incinerator.*
Many operational modifications were
incorporated into the unit such as fully
modulated burners, gravity ash removal,
steam injection capability, and enhanced
'Mention of trade names or commercial products
does not constitute endorsement or recommenda-
tion for use.
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mixing of secondary air with primary
chamber effluent. Many of these are not
available as standard options on the basic
unit; other modifications were made to fit
the needs of DOE operations at Los
Alamos. The basic incinerator and associ-
ated offgas cleaning equipment are
schematically presented in Figures 1 and
2.
Test Plan
The purpose of the research was to
determine the destruction efficiency (DE)
for PCP-treated wood as a feed component
to the CAI while simulating conditions
obtainable in a proposed disposal inciner-
ator in the ROK. There was interest in
studying the effects of feed rate, incinera-
tor temperature, and excess air (and,
indirectly, residence time) on the DE for
PCP. Operating conditions included those
that best simulated the proposed inciner-
ator in the ROK. Special interest was also
placed upon identifying conditions which
avoided PIC formation.
PCP-treated wood for testing was
actual ammunition crate wood supplied
for the test runs by DPDS. The test plan
was designed to provide combustion data
over a range of conditions likely to be
employed in a proposed incinerator for
PCP-treated wood disposal. The CAI was
operated at several conditions to provide
parametric data and to model the proposed
unit in the ROK. The research was
conducted in two phases: Phase 1 with
untreated wood and Phase 2 with actual
ammunition boxes. The second phase
consisted of four test periods at various
operating conditions.
Results
Results from analytical work on samples
from the hot zone between the incinerator
chambers and from the secondary cham-
ber offgas are presented in Table 1.
Variations in reported amounts of PCP in
some samples is attributed to an analytical
artifact with a similar retention time in
the HPLC system. The HPLC work was done
to provide preliminary data while problems
with GC/ECD procedures were being
resolved.
The DE for PCP in the primary chamber
was greater than 99.99 percent in all
cases, based on the GC/ECD analytical
data. Results showed that PCP-treated
wood can be incinerated at controlled
conditions so as to achieve greater than
99.9 percent combustion efficiency (CE)
without producing detectable levels of
TCDD or TCDF at detection of limits of 1
ppb and 5 ppb, respectively.
To Exhauster
Offgas Condenser
From
Incinerator
Offgas
r Reheater
Demister
Packed Column
Carbon Bed
Adsorber -
17
-Venturi Scrubber
*- Quench Column
Figure 1. Offgas cleaning subsystem.
• Process HEPA Filter Plenum
Combustion
Chambers
Offgas to Treatment
Combustion Fuel/
Air Supply Glovebox
Ash
Disposal
Side Ram Feeder
Figure 2. Basic controlled air incinerator.
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Experimental
Test Phase 1, Period 1
i Untreated wood, establish operating baseline
i Conditions
:eed Rate
.ower Chamber Temperature
\fterburner Temperature
.ower Chamber O2
\fterburner 02
'esting Period
Test Phase 1 , Period 2
1 Untreated Wood
> Conditions
:eed Rate
.ower Chamber Temperature
Afterburner Temperature
.ower Chamber Oz
\fterburner 02
esting Period
Test Phase 2, Period 1
> PCP treated ammo boxes
i Conditions
:eed Rate
.ower Chamber Temperature
Afterburner Temperature
.ower Chamber Qz
Afterburner 02
"esting Period
Test Phase 2, Period 2
i PCP treated ammo boxes
i Conditions
Feed Rate
Lower Chamber Temperature
Afterburner Temperature
Lower Chamber 02
Afterburner 02
Testing Period
Test Phase 2, Period 3
• PCP treated ammo boxes
• Conditions
Feed Rate
Lower Chamber Temperature
Afterburner Temperature
Lower Chamber Oz
Afterburner 02
Testing Period
Test Phase 2, Period 4
• PCP treated ammo boxes
• Conditions
Feed Rate
Lower Chamber Temperature
Afterburner Temperature
'.ower Chamber 02
Afterburner Oz
Testing Period
Sample 1
60 Ib/h
916°C Avg.
1010°CAvg.
6% Avg.
11% Avg.
4 hours
Sample 1
100 Ib/h
1004°CAvg.
1093°C Avg.
6% Avg.
8% Avg.
4 hours
Sample 1
80 Ib/h
918°CAvg.
1099°CAvg.
4% Avg.
8% Avg.
4 hours
Sample 1
65 Ib/h
927°C Avg.
1202°CAvg.
5% Avg.
7.5% Avg.
4 hours
Sample 1
90 Ib/h
1027°CAvg.
1203°CAvg.
5% Avg.
6.5% Avg.
4 hours
Sample 1
65 Ib/h
954°C Avg.
1210°CAvg.
1%Avg.
7.5% Avg.
4 hours
Sample 2
60 Ib/h
927°C Avg.
1010°CAvg.
6% Avg.
1 1 % Avg.
4 hours
Sample 2
85 Ib/h
1000°CAvg.
1093°C Avg.
6% Avg.
8% Avg.
4 hours
Sample 2
90 Ib/h
1002°CAvg.
1104°C Avg.
4% Avg.
7.8% Avg.
4 hours
Sample 2
70 Ib/h
938°C Avg.
1210°CAvg.
6% Avg.
7% Avg.
4 hours
Sample 2
85 Ib/h
1032°CAvg.
1204°CAvg.
5% Avg.
6% Avg.
4 hours
Sample 2
60 Ib/h
916°CAvg.
1174°CAvg.
0.5% Avg.
8% Avg.
4 hours
Conclusions
PCP-treated wood was incinerated in
the CAI at Los Alamos under a variety of
test conditions and a DE of >99.99
percent was observed. Analytical results
from several sources showed no evidence
of TCDD at a detection limit of 1 ppb or
TCDF at a detection limit of 5 ppb. The DE
is greater than 99.99 percent for the pri-
mary chamber alone, indicating that such
a DE can routinely be accomplished in a
single chamber unit if proper conditions
are maintained.
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Table 1. Analysis of PCP Test Samples
Results* (in sample)
Sample**
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
HZ
Ash
Scrub
liquids
HZXAD-2
OG XAD-2
HZ XAD-2
OG XAD-2
HG XAD-2
OG XAD-2
HZ XAD-2
OG XAD-2
Sample from
Phase Period Interval
1 1 1
1 1 2
1 2 1
1 2 2
2 / 7
2 / 2
2 2 1
222
2 3 1
232
2 4 1
242
individual samples from
all test intervals
individual samples from
phase 1 and each
phase 2 period
composite of all
phase 2 periods
2 2 /
2 2 1
2 4 r
2 4 r
242
242
composite of other phase 2
composite of other phase 2
by GC/ECD
PCP
MJf
NO
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
TCDD
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
TCDF
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
by HPLC
PCP
ND
ND
ND
ND
1.64 ppm
ND
ND
ND
ND
ND
0.41 ppm
5.09 ppm
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
by GC/MS
PCP
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
-tt
—
—
—
—
—
—
—
—
TCDD
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
—
—
—
—
—
—
—
—
—
TCDF
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
—
—
—
—
—
—
—
—
—
*GC/ŁCD and HPLC by Los Alamos.
GC/MS by Southwest Research Institute.
**Sample HZ = Hot zone between primary and secondary chambers;
OG = Offgas (secondary chamber effluent);
XAD-2 = Sorbent polymer extracts.
t/VD = Below detection limits which are:
15 ppb for PCP by GC/ECD (Los Alamos).
1 ppb for TCDD by GC/ECD (Los Alamos),
5 ppb TCDF by GC/ECD (Los Alamos).
10 ppb for PCP by HPLC (Los Alamos),
170 ppb for PCP by GC/MS (Southwest Research Institute),
17 ppb for TCDD and TCDF by GC/MS (Southwest Research Institute).
ft— indicates not analyzed.
L. A. Stretz and J. S. Vavruska are with Los Alamos National Laboratory, Los
Alamos, NM 87545.
Richard A. Carnes is the EPA Project Officer (see below).
The complete report, entitled "Controlled Air Incineration of Pentachlorophenol-
Treated Wood, "(Order No. PB 84-189 851; Cost: $13.00, subject to change) will
be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield. VA 22161
Telephone: 703-487-4660
The EPA Project Officer can be contacted at:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
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Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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