THE EPA-ORO MOBILE INCINERATION SYSTEM JAMES J. YEZZI, JR., JOHN E. BRUGGER, IRA WILDER, and FRANK J. FREESTONE Oil & Hazardous Materials Spills Branch Municipal Environmental Research Laboratory U.S. Environmental Protection Agency Edison, New Jersey AND STEPHEN M. MAGGIO, RICHARD A. MILLER, and CHARLES PFROMMER, JR. IT Enviroscience Edison� New Jersey ABSTRACT This paper discusses the final design of the mobil e incineration system developed through the EPA Office of Research and Developmen t for the purpose of destroying hazardous material s on site. The incineration system consists of a rotary kiln, a secondary combustion chamber, and an air pollu- tion control section each mounted on a heavy duty trailer. Described herein are: (I) the flue gas moni- toring system developed for this unit; (2) the proposed test burn plan; (3) permitting require- ments; and (4) comments on design, construction, and operating costs. INTRODUCTION Section 104 of the Federal Water Pollu tion Control Act (PL-92-500), as amended, mandates the establishment of rearch programs to develop processes, methods, and prototype devices for the prevention, reduction, and elimination of pollution. Since 1971, a substantial number of pollution pre- vention and abatement methods and equipment have been developed and sponsored by EPA's Oil and Hazardous Materials Spill s (OHMS) Branch, located in Edison, New Jery, through grants, contracts, and in-house projects. Adjunct to the OHMS Branch is the on-site, , contractor-operated Environmental Emergency Response Unit (EERU). EERU personnel assist the OHMS Branch in the design, fabrication, evaluation, and demonstration of prototype equipment. 199 Development of the Mobile Incineration System (Fig. I), was initiated in February 1977. MB Asso- ciates (now Tracor-MBA), San Ramon, California, initiated the design and fabricated the principal components of the system through September 1980, at which time the unit was delivered to the EERU for completion. Subsystem design and fabri- cation was performed by the operating contractor of the EERU - Mason & Hanger-Silas Mason Com- pany, Inc., Lexington, Kentucky - from ptember 1980 through May 1981. In June 1981, the EERU contract was competitively awarded to IT Enviro- science Inc., Knoxville, Tennessee. IT personnel completed the subsystem design, assembly, modi- fication, and testing. The mobile incineration sys- tem was initially tested during October 1981, and within three days from the startup date, the system met the design operating conditions. SYSTEM DESCRIPTION The mobile incineration system has been de- signed and built to provide a mobile facility for on- site thermal destruction/detoxification of hazard- ous and toxic organic substances. The total system consists of: (I) major incineration and air pollution control (APC) equipment mounted on three heavy duty, over-the-road, semi-trailers; (2) combustion and stack gas monitoring equipment housed within a fourth trailer; (3) ancillary support equipment. As ill ustrated in Fig. 1, the mobile incineration sys- tem consists principally of a: (I) rotary kiln; (2) condary combustion chamber (SeC) ; (3) wetted-
Transcript
THE EPA-ORO MOBILE INCINERATION SYSTEM
JAMES J. YEZZI, JR., JOHN E. BRUGGER, IRA WILDER, and FRANK J. FREESTONE Oil & Hazardous Materials Spills Branch
Municipal Environmental Research Laboratory
U.S. Environmental Protection Agency
Edison, New Jersey
AND
STEPHEN M. MAGGIO, RICHARD A. MILLER, and CHARLES PFROMMER, JR. IT Enviroscience
Edison� New Jersey
ABSTRACT
This paper discusses the final design of the mobile incineration system developed through the EPA Office of Research and Developmen t for the purpose of destroying hazardous material s on site. The incineration system consists of a rotary kiln, a secondary combustion chamber, and an air pollution control section each mounted on a heavy duty trailer. Described herein are: (I) the flue gas monitoring system developed for this unit; (2) the proposed test burn plan; (3) permitting requirements; and (4) comments on design, construction, and operating costs.
INTRODUCTION
Section 104 of the Federal Water Pollu tion Control Act (PL-92-500), as amended, mandates the establishment of research programs to develop processes, methods, and prototype devices for the prevention, reduction, and elimination of pollution. Since 1971, a substantial number of pollution prevention and abatement methods and equipment have been developed and sponsored by EPA's Oil and Hazardous Materials Spill s (OHMS) Branch, located in Edison, New Jersey, through grants, contracts, and in-house projects.
Adjunct to the OHMS Branch is the on-site, , contractor-operated Environmental Emergency
Response Unit (EERU). EERU personnel assist the OHMS Branch in the design, fabrication, evaluation, and demonstration of prototype equipment.
199
Development of the Mobile Incineration System (Fig. I), was initiated in February 1977. MB Associates (now Tracor-MBA), San Ramon, Cal ifornia, initiated the design and fabricated the principal components of the system through September 1980, at which time the unit was delivered to the EERU for completion. Subsystem design and fabrication was performed by the operating contractor of the EERU - Mason & Hanger-Silas Mason Company, Inc., Lexington, Kentucky - from September 1980 through May 1981. In June 1981, the EERU contract was competitively awarded to IT Enviroscience Inc., Knoxville, Tennessee. IT personnel completed the subsystem design, assembly, modification, and testing. The mobile incineration system was initially tested during October 1981, and within three days from the startup date, the system met the design operating conditions.
SYSTEM DESCRIPTION
The mobile incineration system has been designed and built to provide a mobile facility for onsite thermal destruction/detoxification of hazardous and toxic organic substances. The total system consists of: (I) major incineration and air pollution control (APC) equipment mounted on three heavy duty, over-the-road, semi-trailers; (2) combustion and stack gas monitoring equipment housed within a fourth trailer; (3) ancillary support equipment. As illustrated in Fig. 1, the mobile incineration system consists principally of a: (I) rotary kiln; (2) secondary combustion chamber (SeC) ; (3) wetted-
to
o
o
BU
RN
ER
S
DE
SC
RIP
TIO
N
OV
ER
AL
L W
IDT
H:
2.4
m
OV
ER
AL
L L
EN
GT
H:
45
.7 m
S
TA
CK
HE
IGH
T:
9.1
m
OV
ER
AL
L H
EA
T D
UT
Y:
15
MIL
LIO
N B
TU
/hr
EL
EC
TR
ICA
L R
EQ
UIR
EM
EN
TS
: 1
00
kW
WE
IGH
T T
RA
ILE
R 1
-4
2,0
00
Ib (
19,05
1 kg
) W
EIG
HT
TR
AIL
ER
2 -
57
,000
Ib
(25
,85
5 k
g)
WE
IGH
T T
RA
ILE
R 3
-3
6,0
00
Ib (
16
,32
9 k
g)
CO
MB
US
TIO
N G
AS
AN
AL
YS
IS
(02,
CO
, C
02)
SE
CO
ND
AR
Y
CO
MB
US
TIO
N
CH
AM
BE
R
CO
OL
ING
S
HR
OU
D
FA
N
TE
MP
ER
AT
UR
E:
PR
ES
SU
RE
: G
AS
RE
SID
EN
CE
TIM
E:
EX
CE
SS
OX
YG
EN
:
KIL
N
1 ,0
00
C
EL
BO
W
CH
EA
F
-1
,00
0 P
a +
2 s
ec
4 p
erce
nt
FE
ED
RA
TE
S (
AT
20
PE
RC
EN
T X
S A
IR)
AIR
: 8
5m
3/m
in
FU
EL
OIL
: 2
85
L1h
r W
AS
TE
SO
LID
S:
68 k
g/m
in
WA
ST
E O
IL:
22
7 L
1hr
WA
TE
R:
680
L1h
r
DIS
CH
AR
GE
S
AS
H:
WA
ST
E W
AT
ER
: N
ON
E
+ 1
,000
PA
SC
AL
'" 4
in
H2
0
* D
EP
EN
DE
NT
UP
ON
FE
ED
MA
TE
RIA
L
/ST
AC
K G
AS
AN
AL
YS
IS
(TH
C,
NO
x,
S0
2, 0
2, C
O,
C0
2)
c;:J
SC
C
1,2
00
C
-1
,50
0 P
a +
2 s
ec
4 p
erce
nt
34m
3/m
in
15
0 L
1hr
NO
NE
N
ON
E
NO
NE
AP
C
80
C
CO
NT
RO
L P
AN
EL
-1
0K
Pa +
4 p
erce
nt
NO
NE
N
ON
E
NO
NE
N
ON
E
ST
AC
K
MO
NIT
OR
ING
T
RA
ILE
R
\QJ"(Q)
(J
NO
NE
P
AR
TIC
UL
AT
E F
ILT
ER
ME
DIA
N
ON
E
FIG
.1
E
PA
MO
BIL
E I
NC
INE
RA
TIO
N S
YS
TE
M -
DE
SIG
N S
UM
MA
RY
throat venturi elbow and quench elbow sump;
(4) cleanable high efficiency air filter (CHEAF)* ; and (5) MX (mass transfer) scrubber and an
induced draft (10) fan. Auxiliary equipment con
sists of bulk fuel storage, waste blending and feed equipment, scrubber solution feed equipment, ash receiving drums, and an auxiliary diesel power generator. A block flow diagram of the system is
shown in Fig. 2. The mobile incineration system is controlled
and monitored via electrical relay logic and con
ventional industrial process instrumentation and hardware. Safety interlocks and shutdown features comprise a major portion of the control system. Fuel, waste, and combustion air feed rates, combustion temperatures, and stack gas concentration of carbon monoxide (CO), carbon dioxide (C02), and oxygen (02) are continuously monitored, thus
assuring compliance with regulatory requirements.
TRAILER 1 - ROTARY KILN
The first trailer, shown in Fig. 3, carries the rotary kiln with a waste liquid/sludge feed nozzle, the solids ram feed unit, a combustion air blower, two hydraulic power units, and the main combustion system control panel. The geometry of the rotary kiln is the maximum allowable to insure
compliance compatible with trailer size, weight, and axle loading constraints imposed by over-theroad limitations and state highway regulations.
The rotary kiln is a 6 in. (I 5.2 cm) thick refrac
tory-line, direct-fired, co-current flow unit
• Mention of trade names or commercial products in this
paper does not constitute endorsement or recommend·
ation for use by the U.S. Environmental Protection
Agency.
SAMPLE
FUEL OIL
designed to operate at up to 1,832 F (1,000 C)
with a nominal solids retention time of 1 hr. Solids retention time is a function of the rotation
al speed and slope (adjustable) of the kiln. The unit is fired with two 4 in. (10.2 cm) fuel oil burners that provide high turbulence and short flames. One of the two trailer-mounted hydraulic drive units is used to rotate the kiln, while the other unit powers the solids ram feed system.
The hydraulically operated ram feed delivers solid wastes into the kiln. It includes an externally loaded hopper and is capable of feeding an adjustable volume and cycle rate of up to 2 ft3 (0.057m3) of solids in 30 sec as well as partial volumes over longer periods. Waste liquids and sludges are fed to the rotary kiln from a feed system that is not mounted on the trailer. The waste liquid is atomized with compressed air supplied through the kiln feed nozzle. Atomized water is fed to the kiln through an adjacent nozzle to serve as a heat sink for temperature control. The combustion air
blower provides atomizing and combustion air to
both burners as well as excess air to the combustion chamber. The main control panel for both the primary combustion chamber and the secondary combustion chamber (mounted on Trailer 2) is
mounted on the first trailer.
TRAILER 2 - SECONDARY COMBUSTION CHAMBER
The secondary combustion chamber, combustion air blower, and the quench elbow are mounted on the second trailer (Fig 4). The 52 in. (1.32 m)
10 by 36 ft (11 m) long secondary combustion chamber is lined with 6 in. (15.2 cm) of castable refractory and is designed to provide 2.2 sec of
AIR ��-===�;:�3 E=::�l-PROPANE WATER WATER OFF GAS
WATER ___ _
LIQUID/SLUDGE _
WASTE OIL =�� SOLIDS RAM
ROTARY __ KILN
ASH
COMB.
CHAMBER
SAMPLE
QUENCH
ELBOW
QUENCH
SUMP
SAMPLE
CHEAF
L...,;S;,;;UMP
PURGE
WATER
SCRUBBER
SUMP
SAMPLE
FAN
-WATER
ALKALINE
TANK
FIG. 2 BLOCK FLOW DIAGRAM OF MOBILE INCINERATION SYSTEM
201
STACK
retention time for completion of the combustion process. Two tangentially mounted oil fired burners, similar to those in the rotary kiln, are located at the inlet of the secondary combustion chamber; they are designed to maintain the temperature in
the chamber up to 2,200 F (1,200 C). Mixing of gases is achieved by an Inconel 601 baffle with swirl vanes located at the entrance to the chamber and by the tangential firing of the burners. This design, in conjunction with a gas stream velocity of
15 ft/sec (0.4 6 m/sec), results in a Reynolds Num
ber of approximately 30,000 (turbulent flow).
Atomizing, combustion, and excess air is provided by a combustion air blower. In order to control the shell temperature, the secondary com
bustion chamber is enclosed in a shroud through which air is blown by a second trailer-mounted
blower. The wetted-throat venturi quench elbow is
located on the exit of the secondary combustion chamber. The flue gases are cooled from 2,200 F (1,200 C) to approximately 190 F (88 C) by eleven
water spray nozzles using an excess amount of
recycle and makeup water. The water spray drains
RAM FEED AND
KILN DRIVE
HYDRAULIC U�ITS
COMBUSTION
AIR BLOWER
\
CONTROL (i
SOLIDS RAM
FEED SYSTEM -\\
PANEL
I� -/ I "
PRESSURE
BLOWER
-- -- --
BURNERS
l
ROTARY
KILN
10' 10'
"
'10"
DU CT TO
SCC
AS
--- --
-- --
H CHUTE
1. PRESSURE BLOWER: Maxon Series FG, FRP Housing, 20-hp (15-kW) motor. 200sig (0.088 kg/em') at 2,480 SCFM (1,110 LIsee)
(2 fe max., 30 SE'G :nin), ram section in kiln atmosphere mad& of Inconel 671, hopper gate cylinder is Cunningham hydraulic cylinder
Maxon Multifire 11, 28 gph (0.03 LIsee) max of #2 fuel oil,
12 to 1 turndown ratio, propane pilot, Maxon Omni-Ratio oil control regulators (2)
North American oil tube and nozzle, air atomized, 40 psig (2.8 kg/em')
North American oil tube and nozzle, air atomized, 40 psig (2.8 kg/em')
Carbon steel (A-36) shell lined with 6 in. (15 em) A.P. Green Kast�-Lite 30 refractory, 16 ft (4.9 m) length by 52 in. (132 em) 10 volume 236 ft3 (6.7 m3)
I nconel 601, two flap door unit, doors operated by Pneumatic Actuator Model no. DS-4-2
Inconel 601 with tapered section, 32 in. (81 em) ID to 20 in. (51 em) 10
FIG. 3 TRAILER SYSTEM DESCRIPTION
202
SECONDARY COMBUSTION
CHAMBER
COMBUSTION AIR BLOWER
COOLING SHROUD
FAN
1. KILN-SCC DUCI: Ineonel 601, 20 in. (51 cm) ID
2. SECONDARY COMBUSTION CHAMBER: Carbon steel (A-36) shell lined with 6 in. (15 em) of A.P. Green Kast.Q-l..ite 30 refractory, 36 ft (11 m) length by 52 in. (132 em) ID, volume 531 ft3 (15 m3) , forced draft cooling annulus
6. QUENCH ELBOW: 90 deg. venturi elbow, Inconel 625. internal water spray cooling using eleven 316 SS Sflray nozzles, 80 gal/min (5.1 Lisee) water flow
FIG.4 'fRAILER 2 SYSTEM DI:SCRIPTION
to the quench elbow sump and is recirculated to the quench elbow at 80 gpm (5.1 Lisee).
TRA ILER 3 � AIR POI.LUrlON CONTROL.
As illustrated in Fig. 5 , a skid-mounted quench surge sump and recycle pUmp is located on the ground between Trailers 2 and 3. The quench system is the initial stage of the air pollution control (APC) system In that the cooling and saturation of the gases preconditions them for the rest of the APC system. through pH adjustment with an alkaline solution, the excess water in the quench removes part of the acid gases in the flue gas. If the quench water pH drops below 7, alkaline solution is added to the quench sump ftom auxiliary alkaline supply tanks. Some particulate is also removed in the quench.
Mounted on the third trailer are the particulate scrubber, mass transfer scrubber, induced·draft fan, fan drive engine, flue gas stack instrumefl t air compressor and control parteL the particulate scrubber is a commercially available cleanable high Hfidertcy air filter (CHEAl') constructed of lllconel 625 for wet corrosIon tesl$bnce. 1t operates with a 30 in. w.e. (740 1>a) pressUre tHfferertthtl across a wetted
203
fiberglass filter mat to remove submicron particulates from the flue gases.
The mass transfer scrubber is a horizon tal, crossflow irrigated, packed bed absorber tower appropriately designed and reinforced for this specific mobile application. The packed bed has a 2 5 ft2
(2.3 m2) cross-section and is over 8 ft (2 .4 m) long, with the last 9 in. (22 .9 cm) of packing acting as a detylistef. The scrubbing media is kept alkaline by automatic pH adjustment from an off-trailer alkaline solution feed system. Sumps are located in the bottom of the packed scrubber for both it and the CHEAF. Recycle pumps are also utilized for both scrubber units.
The induced-draft fan is driven by a 15 5 hp (I 16 kW) diesel engine and operates at a nominal speed of 3,35 0 rpm in order to maintain a negative presSure of 43 in. w.e. (10,700 Pa). The fan is a single stage, he!lVY duty industrial unit with a 304 stainless steel housing and an Inconel 625 shaft and 36 in. (0.91 m) diameter rotor.
the eXhaust stack is mounted on top of the fan and is hinged so that it will lay down in a horizontal position during transport. 1>art of the stack is a sound attenuator deSigned to reduce the fan discharge sound pressure levels to 85 db at 5 ft (I.sm)
Inconel 625,36 in. (91.5 cm) width X 72 in, ( 183 cm) length X 30 in. (76 cm) height
Inconel625, 20.4 in. (52 em) 10
Inconel 625, mechanical operated, includes butterfly shutoff valve
Anderson 2000, Inconel 625, Wetted glass fiber filter pad with automatic controls to maintain 30 in, (76 cm) WC /:; P, pad is 100 ft (30,5 m) roll by 4 ft ( 1.2 m) width, moved by Inconel 625 chain mat
Ceilcote cross-flow irrigated scrubber filled with 2 in, (5 cm) plastic packing, 7.8 ft (2.4 m) height X 6,5 ft (2 m) width X 29 ft (8,9 m) length, FRP
304 SS, 12 in. (30,5 em) dia.
347 SS housing, Inconel 625 shaft and impeller, 36 in, (91,5 em) dia. rotor
Two sections 9 ft (2.7 m) noise attenuator, carbon steel 10 ft (3,1 m) section, 304 SS
FIG.5 TRAILER 3 SYSTEM DESCRIPTION
from the stack outlet. The overall height of the stack is 30 ft (9.1 m) above ground level. Also mounted on the third trailer is the control panel used to operate all the equipment on the trailer. The air compressor on the trailer provides instrument air for all three trailers.
SAFETY INTERLOCKS
The mobile incineration system uses electrical relay logic and conventional industrial process instrumentation and hardware. Instrumentation is designed to monitor process conditions, provide data for assuring compliance with regulatory requirements, and assure appropriate process response and control, operational flexibility, and safety interlocking and shutdown features. The
safety interlocks and shutdown features comprise a major portion of the control system.
Safety shutdown responses identified in Table 1 are relayed to various equipment items when certain process limits are reached or not met. In general, the process parameters that alert and initiate responses to alarm conditions are:
1. High and low kiln temperature. 2. High and low secondary combustion chamber
oxygen (02) level. 4. Low flow in the quench, particulate scrubber,
or mass transfer scrubber sumps.
204
5. Very low level in the quench, particulate scrubber, or mass transfer scrubber sumps.
tv
o
VI
KIL
N B
UR
NER
S
SCC
BUR
NER
S
EMER
GEN
CY V
ENT
ID F
AN
CAU
STIC
FE
ED
PU
MP
QU
EN
CH S
UM
P PU
MP
KIL
N R
AM
FE
ED
-W
ASJ
.E.J}
lL .F
�ED
TA
BL
E 1
SA
FE
TY
IN
TE
RL
OC
K S
YS
TE
M
xl:lllxll
lxl�lxlll
ll�IIII
�l x I(
EY:
_.
,I
X -
""fWlN
.S 0
FF
S
-ST
AR
TS
0-
OPE
NS
S
0-
BLAN
K I
ND
ICA
TES
EQU
IPMEN
T ST
AY
S ON
, A
LAR
M B
UZZ
ER
SO
UN
DS
6. High gas temperature or pressure in the quench section.
7. High pressure at the induced-draft inlet. 8. High vibration of the induced-draft fan. 9. Insufficient burner air or fuel supply. The fuel oil burner system includes an internal
interlock system that shuts down the burner system (i.e., fuel oil flow) if: (1) a flame is detected during pre-ignition; (2) the pilot fails to ignite; (3) the burners fail to ignite; or (4) there is a loss of flame after ignition. A shutdown of the burners automatically stops waste feeds.
During an alarm condition, waste and fuel oil feeds are immediately stopped. When required the induced-draft fan is shut down and the emergency vent located between the quench sump and CHEAF opens. All recycle and makeup water flows are maintained, if possible, to prevent overheating in the mass transfer scrubber. The safety interlock system is designed to provide protection both for operating personnel and for the incineration equipment.
STACK MONITORING SYSTEM
Since the mobile incineration system was designed to safely destroy or detoxify a wide range of hazardous wastes, an important aspect of the design was to provide a monitoring system which analyzes the flue and stack gases for combustion components [carbon monoxide (CO), carbon dioxide (C02), and oxygen (02)] and emission components [(oxides of nitrogen (NOx), sulfur dioxide (S02), and total hydrocarbons (THC)] . The stack monitoring system principally serves two critical functions: (1) it provides the operators with current data on the perfonnance of the incineration and gas cleaning processes; and (2) it generates and records accurate data on the gas emissions from the process. This ensures operator safety and compliance with operating permit requirements. Functional requirements were met by the selection of a dual gas chromatograph (GC) system that possesses a high level of reliability and versatility, and conforms to the mobile nature of the incineration system.
The selection of a process GC over other available monitoring systems was based on the ability of a single vendor to provide a complete analytical system that could withstand the extreme operating conditions of the mobile incinerator. The previously cited conditions, in conjunction with the very nature of chemical waste incineration, produce an extremely difficult gas sampling environ-
206
ment-hot 2,200 F (I ,200 C), wet (50 percent water), and dirty [1-2 gr/scf (2.3-4.5 g/Nm3)]. The stack gas monitoring system selected consists of three subsystems:
(1) Gas sampling/conditioning. (2) Gas analYSis/analyzer calibration. (3) System control/results reporting.
GAS SAMPL ING/CONDIT ION ING
The gas sampling conditions in the mobile incinerator present the most difficult (hot, corrosive, wet, and dirty) aspect of the gas analysis. In order to reliably and accurately extract and condition, cool and dry gas samples under these conditions, two Bendix Model 8901C Stack Probe/Conditioning Assemblies were selected. Several favorable characteristics of this model are the use of materials of construction that are highly resistant to corrosion and the ability of the assembly to cool and dry gas samples with very little loss of the samples' components.
Two gas sampling/conditioning assemblies are used to provide separate gas samples for the measurement of combustion parameters and emission levels. The gas sampling/conditioning subsystem consists of two identical assemblies; one assembly is mounted on the exit duct from the SCC prior to gas quenching and the second assembly is mounted on the incinerator stack. The need for separate samples for each analysis arises from the desire to optimize the combustion gas analysis (CO, CO2, and O2) by extracting the sample as close to the incineration process as possible. These assemblies feed conditioned gas samples through umbilical tubes to the gas analyzer and control units which are housed in a fourth trailer that is dedicated to analytical support.
Since the combustion gas sampler/conditioner assembly will collect a sample at the SCC exhaust prior to gas quenching, the gas sampled: (a) will be relatively dry which minimizes potential problems in the gas sampling/conditioning unit; and (b) has not been diluted with ambient air which occurs from in-leakage through openings in the negatively pressured air pollution control equipment. Accurate combustion gas analysis is important in order to report representative combustion efficiency (according to Eq. 1) for permit compliance and to allow optimization of the incinerator's performance.
Combustion Efficiency = CO2 C��O X 100 (1)
where CO2 = concentration of carbon dioxide CO = concentration of carbon monoxide
The second stack probe/conditioning assembly is located on the incinerator stack to collect gas samples for emission measurement. Construction and operation of these assemblies is identical.
Gas sampling is done with a corrosion and temperature resistant ceramic probe which extracts gas samples from the center of the process duct. The extracted sample passes through a ceramic inertial filter, located inside the probe, to remove particulate material (5 !lm) from the gas sample. Next, the filtered gas sample is partially cooled in an air-air heat exchanger to lower the temperature to 212-248 F ( l 00-120 C); entrained liqUids are collected in a liquid trap at the bottom of the exchanger. The gas sample then passes through a vaporizer 248 F (120 C) to ensure all entrained liquids from process or instrument upsets are vaporized before the gas drying process. Gas drying is accomplishe� in a Perma Pure dryer which removes water vapor from the gas sample without uSing a condensation process that often scrubs key gas components from the sample. The drying process transfers the water vapor from the gas sample through a tubular plastic membrane to clean, dry [110 F (43.3 C) dew point 1 , sweep air on the outside of the dryer. The filtered, cooled and dried gas sample is then transported to the analyzers (discussed in the next section) through Teflon tubing. Pressure switches in the stack probe/conditioning assembly monitor gas sampling and conditioning operation for particulate build-up or plugging. When appropriate, the unit automatically back-purges itself with steam or compressed air to maintain reliable, longterm untended operation.
GAS ANALYS IS/ANALYZER CALIBRATION
The cleaned gas sample, from the combustion gas and stack sampler/conditioning assemblies, enters the analyzer section of the system through a Bendix Model 890B Dual Stream Transport Assembly. The transport assembly delivers the gas sam· pies from either gas sampling location to the appropriate analyzer. The analyzer section operates in conjunction with the monitoring system controller to divert gas samples: (1) to the thermal conductivity detector GC for analysis of CO2, O2 , and S02 ; (2) through a methanizer to a flame ionization detector GC for analysis of CO; (3) to the flame ionization detector GC for analysis of THC; and (4) a chemiluminescent detector for analysis
of NOx' The analyzer section also introduces calibration gas, from cylinders, through the sampling/ conditioning units to the appropriate analyzer. The 'analyses conducted by the continuous analyzers ate summarized in Table 2. the decision was made to Use process gas chromatographs to perform the majority of the analyses for the following reasons: (1) the expensive analyzer detectors would be protected from corrosive gases or submicron particulate, which may be present due to process upsets or failure of the sample conditioning system, by a relatively inexpensive GC column; (2) the frollt end components of a GC system, such as tUbing and sampling valves, are readily available in the corrosion resistant materials that are required to transport gas samples; (3) the versatility of a thermal conduchvity/flame ionization GC system permits simple and inexpensive modifications to the gas analysis to include additional or very specific components; (4) gas chromatography offers the ability to more readily remove interfeting components from a gas sample prior to reaching the analyzers than do spectrometric analyzers; and (5) the components of the analyzers are more resistant to problems associated with a mobile field system, i.e" vibration. Calibration of the analyzers is accomplished using cYlinder gas standards which are injected into the monitoring system at the sample probes. This calibration method not only calibrates the analyzers but accounts for component losses that are related with sample conditioning and trans· portation. Calibration of the analyzers is directed by the monitoring system controller on a repeated, specified basis.
SYSTEM CONTROL/RESULTS REPORTING
Two microprocessors control: (1) the two gas sampling/conditioning assemblies; (2) the sample transport and calibration systems; and (3) the gas analyzers, One of the microprocessors is dedicated to controlling the flame ionization Ge. The second microprocessor controls the thermal conductivity CC, collects data from the chemiluminescence de· tector, and generates analytical reports on a remote computer terminal.
In addition to controlling GC functions, the microprocessors continuously: (1) control analyzer calibration (zeto, span and drift) and sequencing of sampling probe back flush; and (2) monitor for low flow of calibration gases, for low flow of gas sample, for high component concentration and system utilities. The ability of the microprocessor to
207
TABLE 2
Sample Analysis Component Location
Combustion CO SCC
Gas
Combustion CO2 SCC Gas
Combustion O2 Stack Gas
Stack Gas NOx Stack
Stack Gas S02 Stack
Stack Gas THC Stack
completely monitor and operate the samplers and analyzers permits operation of the mobile incinerator in remote locations with a minimum technical staff. In addition, the continuous monitoring of the analytical system operation is required by federal regulation during the burning of PCBs. As well as controlling the entire analytical system, the microprocessors perform another important task. That task is the generation of calibration reports, analytical result reports, time-weighted average reports, analytical system alarm conditions, and incinerator excess emission reports. All of these reports are important to comply with regulatory permits and to allow optimization of the incinerator's performance.
SYSTEM TESTING
PERMITS
Prior to the operation of the mobile incineration system at EPA's Edison, New Jersey facility, various permit applications were submitted to comply with Federal, State, and Municipal mandates (see Table 3).
PERFORMANCE TEST
Initial startup and operation of the mobile incineration system with fuel oil during the week of October 12, 1981, proved to be very successful. The system reached the design operating conditions of 1,800 F (1,000 C) in the rotary kiln and
Analysis Analysis Analyzer Range Time
Methanizer-GC/FID 0-350 ppm 6 min Bendix Model 9220
GCITC 0-10 percent 6 min Bendix Model 9120
GCITC 0-8 percent 6 min Bendix Model 9120
Chemiluminescence 0-200 ppm on line Bendix Model 8102
GCITC 0-2000 ppm 6 min Bendix Model 9120
GC/FID 0-200 ppm 6 min Bendix Model 9220
208
2,200 F (1,200 C) in the SCC burning auxiliary fuel alone within three days of the initial starting attempt.
During the performance tests, many subsystem function and reliability tests were successfully performed. These tests demonstrated that: (1) the kiln and secondary combustion chamber can be operated at design temperatures with fuel oil; (2) the induced draft fan can maintain a vacuum on the system; (3) the various design flow rates (air, fuel, water) can be achieved; (4) the system's controls, monitoring equipment and safety interlocks function properly; and (5) that all ancillary equipment operates properly when integrated with the system.
Upon completion of the performance tests, the system was partially disassembled and inspected. The data and results of the performance tests and inspection are being compiled and evaluated for possible modification of the system. The system's ability to thermally detoxify hazardous and toxic wastes will be evaluated during the proposed trial burns.
TRIAL BURN PLAN
The trial burn plan consists of nine independent test burns which can be grouped into three test phases. During phase one, a baseline test will be performed for data comparison purposes. This test will utilize only commercial quality No.2 fuel oil. A subsequent test burn will utilize a mixture of iron oxide and No. 2 fuel oil to measure the par-
TABLE 3 PERMIT REQUIREMENTS FO R OPERATION OF EPA'S MOBILE INCINERATION SYSTEM AT GSA-RARITAN DEPOT IN EDISON, NEW JERSEY
FEDERAL PERMITS Title of Permit
Clean Air Act
Toxic Substances Control Act (TSCA)
National Environmental Policy Act (NEPA)
Resource Conservation and Recovery Act
(RCRA)
National Pollutant Discharge Elimination System (NPDES)
STATE PERMITS
Incinerator Permit Application for Air Pollution Control
New Jersey Pollutant Discharge Elimination Systems Permits (NJ-PDES)
Division of Hazard Management Permit (DPCC, DCR permit)
MUNICIPAL PERMITS
Middlesex County Utility Authority Discharge Permit
40 CFR 52.21, Prevention of Significant Air Quality Deterioration Regulation (PSD regulation)
40 CFR 761.40, Polychlorinated Biphenyls (PCBs), Manufacturing, ProceSSing, Distribution in Commerce, and Use Prohibitions
40 CFR Part 6, Agency Implementation of National Environmental Policy Act
40 CFR Parts 261, 262, and 265 Treatment Storage or Disposal of Hazardous Wastes
National Pollutant Discharge Elimination system under the Clear Water Act, 33 U .S.C. 1251. Discharge of Pollutants into the waters of the United States
New Jersey Department of Environmental Protection Administrative Code Title 7, Chapter 27; Subchapter 8, Perm its and Certificates
New Jersey Pollutant Discharge Elimination System 58: 10 A-1, et. seq.
Covered under New Jersey Hazardous Waste Management Regulations, 7026-1 , et. seq.
Covered under Rules Concerning Discharges of Petroleum and Other Hazardous substances (N.J.A.C. 7.1 e-1 et. seq.; Subchapter 3 Discharge Cleanup Operations)
Permit required by the authority for the discharge of process water into their systems
ticulate removal efficiency of the air pollution control (APC) equipment. The destruction and removal efficiency (DRE) of the mobile incineration system for o-dichlorobenzene (ODCB)-a surrogate polychlorinated biphenyl (PCB)-and "Askarel"
tion will include material and energy balances for each run to determine the accuracy of the testing measures and procedures. During the second test burn, a synthetic mixture of iron oxide (Fe203) particulates and commercially available No. 2 fuel oil will be fed through the waste oil nozzle to generate 0.5 gr of particulate per standard cubic foot of off-gas in the SCC. The sampling points that will be utilized during this test are located in the quench sump exit and in the stack in order to provide data for the determination of particulate removal efficiencies for the CHEAF and packed scurbber combined. A material balance around the air pollution control equipment will provide particulate removal efficiency information.
(a typical PCB formulation), will be analyzed in the second and third test phases. Tables 3 and 4 summarize the scope and schedule of the trial burn plan. The feed material during the baseline trial will be commercial quality No. 2 fuel oil. For all tests, the .kiln and SCC will be brought up to temperature by burning fuel oil through the fuel oil burners. For this test, fuel oil will be fed through the waste oil feed nozzle and the kiln fuel oil burners will automatically turn down to control the kiln temperature. The fuel oil will be analyzed along with the ash, purge water, and stack gas to provide baseline data. Baseline data reduc-
209
Chlorinated organic DRE and HCI removal efficiency tests will be performed subsequent to the particulate removal tests. Fuel oil will be spiked
TABlE 4 SUMMAR)' OF TRIAL BURN SCOPE AND ACTIVITIES
TESTS R,moval Emi�iQn
Cate- Te$t Test Test P-arti- Other Total
9Qry �opea Phase No . Dayb DREC Held culate PCDDe pcaf PCDF9 POHCh RCli
a AU con.centratiQIiI.$ on iil w.ight basi$. b Da.y!> b,etween te.ts for analyses (See Table. 2),. c De!>t,uc.tion ar;>Q remQval, e·fficiency. d Hydrocl1lo.ric acid. e Polychlor inateq dibEtnzo diQxins. f PolychlQrinated biphenv.ls. � Pr01\Cchiarinated dlbenzo, fu,rans. h i>rinc;iple organic naza.qous component. i Chlorinated oFganic.
X
X
X.
X
X.
�
X
with ODCB to con«entration levels of 1 , 5 , and 25 weight percent chlorine. The stack gas and feed data will be used to calculate the DRE� for ODCR and HCl removal effic�encies.
The last test wOO establish the mobile incinerator's ability to, destro.y res. contaminated materi� al. Fuel oil will be sp.iked to ll�\l'els of 0.05 , 1,10, and 20 weight percent PCB. These oU and PCB mixtures will be fed to the 1.<.iln after the required operating conditions have been achieved with fuel oil only. The stack gas, feed pur� wateI, and ash analyses data will be used to calclliate DREs of the PCBs.
The cQJlcentnttion of polycWorinat�d d.ibenzo dioxins (FCDDs) and polychlorinated dtbenzo futans (PCDFs) will be monitoled during all phases of testing except during the particulate removal efficiency test (see Tables 4 and 5 }.
In summary, the filst test phase begins with a perfoFmance evaluation for a nonha2afdous feed and concludes. with a feed containing a low level of ODCB. If the tesults indicate that the system will reliably destwy the chlorinated organics and
X X
X X X
X X X
X X X )(
X X X X
X X X X
X X X X
X X X X.
also remove the particulates and acid gases, a second phase of testing will be conducted. The second test phase of the trial hurn plan is designed to determine the system's DRE and acid gas removal capahilities with increasing ODCB concentrations. After these tests, a very low PCB concentration test will be made to s.erve as. an indicatoI for the third phase of testing. If the analysis of the second phase data is either inconclusive or negative, the testing program will be redefined. Positive results will initiate the thila phase of these \}urns, which is DRE testing with PCBs. Three PCB concentration levels will be used.
210
The trial burn plan has been designed to evaluate and demonstrate the mobile inc·inerator's ability to safely destroy ha.zardous and toxic materials in ac.cordance with legislative requirements. In general, this objective will be met by: (1) measuling the ORE for the specified test matelials; (2,. determining parti<;ulate and a«id gas removal efficienci.es under design conditions for the air pollution control equipment; and (3) continuously monitor-. ing the system's operating conditions and emissions.
In addition to defining the performance capability of the system, the data generated will provide background information for subsequent permitting requirements associated with field demonstrations of the mobile incineration system at uncontrolled hazardous waste sites.
COST FACTORS
Approximately $2 million has been spent in the design, assembly, and shakedown of the mobile incineration system. Much of this cost has been incurred due to the development of the prototype system. System design incorporates innovative concepts for providing a system large enough to be feasible, yet small and light enough to meet overthe-road trailer weight limitations. It is very probable that much of the design/development costs would not be re-incurred as other systems are built for similar or industrial specific applications.
Operating costs will vary with the types of wastes being destroyed. For protection of the refractory, the system will be operated continuously around the clock. Three or four operators will be required per shift, depending on the amount of of feedstock preparation. Fuel oil usage will de-
pend on the composition of waste being fed, and will vary from 40 to 100 gal/hr (ISOto 380 L/hr). Power requirements will range from 50 to 100 kW depending on the waste feed preparation systems. Approximately 10 gpm (0.6 L/sec) of water makeup and 5 gpm (0.3 L/sec) of purge are required for the APe system; however, these quantities will increase rapidly if the waste is high in salts and/or chlorides. An alkaline solution will be required to neutralize acid gases scrubbed from the flue gases.
Other costs associated with operating the mobile incineration system include: equipment mobilization, decontamination, and demobilization; site preparation and utility charges. These costs will vary with the nature of the wastes to be detoxified or destroyed and with the location of the site.
In order to encourage its commercialization, detailed plans, specifications, and design drawings of the mobile incineration system are available from EPA.
ACKNOWLEDG MENTS
The authors gratefully acknowledge the assistance and encouragement provided by numerous
TABLE 5 TRIAL BURN PLAN
Day
2
3
4·12
13
14
15
16-24
25
26
28-36
37·58
59-73
Test Phase
2
2
2
3
3
3
Test/ Analyses
Baseline performance of incinerator with fuel oil
Particulate removal capability by feeding No. 2 fuel oil spiked with Fe.03
ORE of OoCB (1 percent CI in fuel oil) and H CI removal efficiency in APC equipment
Analysis of ORE of OoCB , HCI removal efficiency and the formation of any PCoos and PCoFs
ORE of OoCB (5 percent CI in fuel oil) and HCI removal efficiency in APC equipment
ORE of OoCB (25 percent CI in fuel oil) and HCI removal efficiency
ORE of "Askarel" (0.05 percent) in fuel oill and HCI removal efficiency
Analysis of ORE of 5 percent and 25 percent OoCB and 0.05 percent "Askarel", HCI removal efficiency and the formation of any PCoos and PCoFs
ORE of "Askarel" (10 percent in fuel oill·and HCI removal efficiency
ORE of "Askarel" (20 percent in fuel oil) and HCI removal efficiency
Analysis of ORE of 1 percent, 10 percent, and 20 percent "Askarel" plus the formation of any PCoos and PCoFs
Review data from all trial burns
Prepare report on trial burns for submission to regulatory agencies
211
colleagues and friends. In particular, we most sincerely appreciate the effort and cooperation what we received from the following:
1. J. Adams, J. Harris - Arthur D. Little, Inc., Cambridge, Massachusetts
2. S. Anicito, Y. Change, R. Harned, K. Honeycutt, R. Lovell, V. Manolio, T. Pearson, A. Santoro, A. Sherman, C. Stuewe, G. Terryah - IT Enviroscience, Knoxville, Tennessee
3. R. Barton.!' J. Cocherell, J. Custer, M. Manning, J. Nordid, M. Sproul- Mason & HangerSilas Mason Company, Lexington, Kentucky
4. R. Carnes,IE. Oppelt - U.S. EPA Industrial Envir<;mmental--Research Laboratory-Ci, Cincinnati, (i)hio /
•
5. R. Harris, L. Johnson - U.S. EPA Industrial Envir6nmental Research, Laboratory-RTP, Research Triangle Park, North Carolina
6. R. Dewling, K. Stoller - U.S. EPA, Region II, New York, New York
Special thanks are due to M. Sproul, C. Stuewe and K. Honeycutt, each of whom successfully man
aged the Environmental Emergency Response Unit (EPA Contracts 68'{)3-2647 and 68'{)3-3069, respectively) during the design and development of the mobile incineration system. The authors sincerely thank Dot Taylor, U.S. EPA, OHMS Branch, who patiently and pleasantly typed this manuscript.
REFERENCE
(1) Tenzer, R. E., Mattox, W. A., Brugger, J. E., Freestone, F. J., "Design and Testing of Mobile Incineration System for Spilled or Waste Hazardous and Toxic Materials," Proceedings of the 1980 National Conference on Control of Hazardous Material Spills, pp. 467475 .
