OFFICE OF ENFORCEMENT
EPA-330/2-77-007
Coke Plant Evaluation
Kaiser Steel Corporation
Fontana, California
(JANUARY 2 5 -27, 1 97 7]
NATIONAL ENFORCEMENT INVESTIGATIONS
CENTER
DENVER.COLORADO
AND
DIVISION OF STATIONARY SOURCE ENFORCEMENT
W AS H I N GTO N D .C .
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£ Mm %
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MARCH 1977
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Environmental Protection Agency
Office of Enforcement
EPA-330/2-77-007
COKE PLANT EVALUATION
KAISER STEEL CORPORATION
FONTANA, CALIFORNIA
(January 25-27, 1977)
March 1977
National Enforcement Investigations Center - Denver, Colorado
and
Division of Stationary Source Enforcement - Washington, D.C.
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CONTENTS
I INTRODUCTION 1
BACKGROUND 1
PARTICIPANTS 2
APPLICABLE REQUIREMENTS 2
II PROCESS DESCRIPTION 5
III OPERATIONAL PRACTICES AND EQUIPMENT 8
CHARGING 8
Larry Car A1 ignmerit 8
Charge Port Blockage 8
Charge Time Sequence 8
Gas Passage 9
Chuck Door and Lid Operations 11
Gooseneck and Standpipe Openings 11
Coal Bulk Density 13
Aspiration Steam Pressure 13
DOORS 17
Door Cleaning Practices 17
Door and Jamb Conditions 19
Spare Door Availability 20
Collector Main Pressure 20
Door Design 20
Chuck Door Sealing 22
LIDS AND STANDPIPES 22
Luting Practices 22
Physical Condition 23
Collector Main Pressure 23
IV RECOMMENDATIONS 24
CHARGING 24
DOORS 25
LIDS AND STANDPIPES 25
REFERENCES 26
TABLES
1 Peak and Channel Heights 10
2 Average Steam Pressures and
Duration of Emissions 15
3 Collector Main Pressure 21
FIGURES
1 Kaiser Steel Coke Plant 6
2 Percent Air Flow vs. Percent Gooseneck
Area Open
3 Nozzle Pressure vs. Aspiration Capacity
for Single Standpipe 16
i i i
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I. INTRODUCTION
BACKGROUND
Kaiser Steel Corporation operates an integrated steel manufacturing
facility at Fontana, in San Bernardino County, CaliTornia. It has for
some time been the single largest stationary source of air pollution in
the Southern California Air Pollution Control District (SCAPCD).
Since 1970, several operations at Kaiser have been operating under
local variances with compliance schedules. In addition, since April 26,
1976, Kaiser has been under a Federal Consent Decree which requires the
coke ovens and other operations at the facility to meet certain deadlines
for controlling emissions. On July 19, 1976, executives of Kaiser Steel
certified to the Environmental Protection Agency (EPA) that the combined
emissions from the coke oven charging, oven doors and standpipes were in
compliance with the Consent Decree.
The State of California Air Resources Board (ARB) visited Kaiser on
August 30, 1976 to verify compliance with the Decree and observed
substantial excessive emissions from the coke ovens and other opera-
tions. During the week of September 13-16, 1976, a team of 24 inspec-
tors from the ARB, EPA, and SCAPCD conducted an intensive inspection of
Kaiser to determine the magnitude of emission violations. Particular
attention was given to coke oven charging, oven doors and standpipes
which had been certified as being in compliance some months prior. The
inspection of the coke ovens resulted in a total of 1,098 observations
of excessive visible emissions.
As a result of the September, 1976 inspection, EPA Region IX is
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2
entering into litigation against Kaiser. The Regioin anticipates that
Kaiser will claim that the terms of the April 26, 1976 Consent Decree
are not technically feasible.
At the request of Region IX, personnel from the NEIC and EPA Division
of Stationary Source Enforcement (DSSE) conducted an inspection of the
Kaiser coke plant on January 25-27, 1977. The objective was to determine
what specific steps the Company could take, but has not, to meet the
terms of the Consent Decree or to minimize visible emissions. The re-
sults of the NEIC - DSSE inspection are contained in this report.
PARTICIPANTS
J. H. Smith, Director, Environmental Quality Control, Kaiser Steel
Corporation
Gilbert "Bud" Dunn, Asst. Manager, Coke Plant, Kaiser Steel Cor-
poration.
H. Roye Jackson, State of California Air Resources Board
Don Kurosaka, State of California Air Resources, Board
Lois Green, Region IX, EPA
Joe Hopkins, DSSE, EPA
Gary Young, NEIC, EPA
Jon Dion, NEIC, EPA
APPLICABLE REQUIREMENTS
Section IV of the April 26, 1976 Consent Decree between the United
States and Kaiser Steel Corporation is, in part, applicable to coke
oven charging, oven doors and standpipes. Section IV reads as follows:
"Defendant [Kaiser Steel] shall complete or have com-
pleted the following acts with respect to its COKE OVEN OP-
ERATIONS on or before the dates specified:
A. Defendant agrees that by the date of this De-
cree, combined visible emissions from the coke
oven doors and standpipes at each coke oven in
coke oven batteries "A", "B", "C", "D", "E", "F"
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and "G" shall have achieved compliance with San Ber-
nardino County Air Pollution Control District Regula-
tion IV, Rule 50-A (hereinafter Rule 50-A).
B. Defendant shall install stage charging for coke oven
batteries "A", "B\ "C", "D", "E", "F" and "6" accord-
ing to the following schedule:
1. By the date of this Decree - let contracts for the
purchase of control equipment and/or issue work
order for construction or installation of control
equipment or process modification.
2. April 15, 1976 - initiate on-site construction or
installation of control equipment or process modi-
fications.
3. July 15, 1976 - complete on-site construction or
installation of control equipment or process modi-
fications.
4. July 31, 1976 - achieve compliance with Rule 50-A.
Visible emissions from the charging operation,
doors, and standpipes at each oven in coke oven bat-
teries "A", "B", "C", "D", "E\ "F" and "G" shall be
combined in determining compliance."
San Bernardino County Air Pollution Control District Regulation IV,
Rule 50-A reads as follows:
"Rule 50-A. Visible Emission.
A person shall not discharge into the atmosphere from
any source of emission whatsoever, any air contaminant for a
period or periods aggregating more than three (3) minutes in
any one (1) hour which is:
(a) As dark or darker in shade as that designated as No. 1
on the Ringelmann Chart, as published by the United States
Bureau of Mines, or
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(b) Of such opacity as to obscure an observer's
view to a degree equal to or greater than does smoke
described in Section (a) of this Rule.
This rule is effective on June 1, 1972, for all
sources which are not either in operation or under con-
struction prior to that date, and Rule 50 shall not be ap-
plicable to such sources on or after that date., This Rule
is to become effective for all other sources on January 1,
1975 and Rule 50 shall not be applicable on or after that
date."
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II. PROCESS DESCRIPTION
Kaiser Steel Corporation operates a seven-battery coke plant at its
Fontana, California facility. The batteries each have 45 Koppers-design
ovens and are operated as three units: batteries A, B and half of C op-
erate as one unit; the other half of C, D, and E operate as another;
and F and G, which are physically separated from the rest, operate as a
third unit. Each unit has its own coal bunker and quench tower. Bat-
teries A through E have underjet ovens and F and G have gun-flue ovens.
The batteries are equipped with double collector mains. Figure 1 is a
schematic drawing of the plant layout.
Each oven has three charging ports (35.6 cm in diameter) numbered
from push to coke side. Approximately 12.7 m. tons (14 tons) of coal
are charged to the ovens with 35% (±1%) charged to the number 1 port,
25% (±1%) charged to the number 2 port, and 38% (±1.5%) charged to the
number 3 port. The ovens are tapered in width from coke (38 cm) to push
(33 cm) side, are 4.28 m (14 ft) high, and are 12.32 m (40 ft 5 in) long
from door face to door face. All ovens are pushed and charged by the
"Koppers" sequence (l's, 3's, 5's, 7's, 9's, 2's, 4's, 6's, 8's, 11s,
31 s, etc.).
The ovens are equipped with self-sealing doors. The doors on bat-
teries A through E are cam-latch and the doors on F and G are screw-
latch. Three different sets of doors are used. Batteries A and B have
one set; C, D and E another; and F and G a third.
The benches are about 1 meter below the level of the doors. The
doors are removed and replaced by the pusher machine on the push side
and a door machine on the coke side.
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COAl STORAGE
WASTE HEAT STACK
COAL BUNKER
QUENCH TOWER
COAl BUNKER
QUENCH TOWER
CO
COKE STORAGE
COKE STORAGE'
NOTEi Not oil woili hoof
stack* or* shown
Flgur• I. Koittr St**! Cok* Plant
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7
On a 38-oven pushing schedule, each operating unit is staffed by
one larry car operator, one pusher machine operator, one coke side door
machine operator, two bench helpers (one on coke side and one on push
side), and one lidman. The luterman and quench car operator may be
shared with another operating unit. If the pushing schedule is 46 ovens
or more, an additional bench helper is placed on the push side; if the
pushing schedule is 32 ovens or less, the coke side bench helper position
is eliminated.
The coal charged to the ovens during the January inspection ranged
from 35% to 37% volatile matter, 6.3% to 9.8% moisture, 0.73% to 0.85%
sulfur, 6.4% to 6.9% ash, and 68% to 83.5% less than 1/8-mesh. It was a
mix of three types of coal plus 3% petroleum coke. Coking time was
about 22 hours.
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III. OPERATIONAL PRACTICES AND EQUIPMENT
During the inspection, operational practices and equipment having
a bearing on emissions were observed and documented for charging, doors
and topsides (lids and standpipes). The results are discussed below.
CHARGING
Larry Car Alignment
Proper alignment of the larry car drop sleeves with the charge
ports is necessary to assure sufficient oven aspiration, and proper
flow of coal into the oven. Misalignment can create an orifice through
which oven aspiration can be lost, causing charging emissions. No sig-
nificant misalignment of the larry car drop sleeves with the charging
ports was observed.
Charge Port Blockage
Charge ports partially blocked with carbon buildup can interfere
with the continuous flow of coal into the oven, a condition necessary
for successful stage charging. No significant buildup of carbon in the
charge ports was observed.
Charge Time Sequence
Stage charging requires controlled flow of coal into the oven to
allow the gas evolved to be evacuated effectively. The Company operating
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procedure requires coal from hoppers 1 and 3 to be charged simultaneously
into the oven, and coal from hopper 2 to be charged after hoppers 1 and
3 are empty. The time required to empty hoppers 1 and 3 was recorded to
range from 50 seconds to 2 minutes and 22 seconds with an average of 1
minute and 17 seconds for 28 charges. The time required to empty hopper
2 was recorded to range from 1 minute 6 seconds to 2 minutes 46 seconds,
with an average of 2 minutes 3 seconds also for 28 charges. The extra
time required to empty hopper 2 is largely due to the leveling process
which takes place while hopper 2 is emptying.
Proper charging sequence was not always followed by plant personnel.
Instances were recorded when hopper 1 began charging ahead of hopper 3,
and when hopper 2 began charging before hoppers 1 and 3 were empty.
Gas Passage
Proper volumetric distribution of coal introduced into the oven
ensures that sufficient space will remain above the coal to expedite
removal of evolved gases. Kaiser plant officials reported that coal
distribution between hoppers was designed to provide a 30.5-cm (12-in)
channel. Three sets (one per operating unit) of peak and channel
~
height measurements were made during the inspection. The results are
listed in Table 1.
The channel heights for ovens A/9 and C/147 are about 10-15 cm less
than the desired "normal" according to the Company's design criteria of
30.5 cm (12 in).
* Peak and channel heights are defined as the distance between the top
of the coal and the roof of the oven before (for peak) and after
(for channel) leveling. They are measured by placing a measuring
rod into the charging ports.
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Table 1
PEAK AND CHANNEL HEIGHTS
Battery/Oven Type Clearance
Port #1 Port #2 Port #3
(cm)(in)
A/9
Peak
30.5
12
13
5
Channel
23
9
18
7
23
9
C/147
Peak
18
7
23
9
Channel
25.5
10
15
6
18
7
F/253
Peak
51
20
25.5
10
Channel
25.5
10
28
11
33
13
t Distance between coal in oven and roof of oven.
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Roof carbon buildup can effectively reduce the channel height if it
is thick enough; however, no large roof carbon buildup was observed
during the inspection.
Chuck Door and Lid Operations
The time the chuck door is open, prior to the entry -of the leveling
bar and after the leveling bar is withdrawn, should be kept to a minimum
to prevent the introduction of air into the oven and the resultant loss
of steam aspiration effectiveness.
Those times the chuck door was open, prior to the entry of the
leveling bar, were documented while charging emissions were being ob-
served as well as during the two days prior to observing charging. The
times averaged 17.1 seconds with a high of 52 seconds and a low of 7
seconds.
Lids should not be removed from open ports during charging unless
the port is being charged or is otherwise sealed to prevent the intro-
duction of air with an escape of emissions from the oven. The sequence
for removal and replacement of lids at Kaiser was as follows. Lids 1
and 3 were removed for charging and lid 2 was inverted. Then hoppers 1
and 3 were emptied simultaneously. The lid on the charge port for the
hopper which emptied first was replaced, followed by the other lid. In-
verted lid 2 was not replaced until the battery top around oven port 2
was swept.
Gooseneck and Standpipe Openings
The passageway through the goosenecks and standpipes must be kept
clear to obtain maximum aspiration from the ovens. Figure 2 shows the
effect of reducing the gooseneck area upon gas flow from the oven. As
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100
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an example, a 3.8-cm buildup of carbon around the inside perimeter of a
33-cm diameter gooseneck reduces the area by 41%, and, according to
Figure 2, reduces the aspiration by 25%.
During the inspection, four standpipes and twelve goosenecks were
inspected with the aid of a mirror until the mirror broke. Three stand-
pipes and seven goosenecks were free of significant carbon buildup.
Five goosenecks had carbon buildup of 2.5 cm to 5 cm partially or com-
pletely around perimeter, and one standpipe was more than half blocked.
This standpipe was replaced because of a leaking base.
The Company gooseneck cleaning procedure calls for cleaning approx-
imately every fifth set of goosenecks, caps, and nozzles for all shifts.
Cleaning is done manually with a chisel-headed steel bar.
Coal Bulk Density
If the bulk density of the charged coal is low (also indicated by
a high percentage of less than 1/8-inch mesh), the amount of fines
charged to the oven and the potential for emissions increases.
The bulk densities reported by the Company during the inspection
were within the normal range (480 to 800 kg/m3)2 Therefore, bulk den-
sity was probably not a contributing factor to the charging emissions
observed.
Aspiration Steam Pressure
Sufficient aspiration steam pressure at the oven is necessary to
evacuate air and evolved gas from the oven during charging. Insuffi-
cient aspiration steam pressure can be due to low header pressure,
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excessive pressure drop in the lines, blocked or partially blocked
nozzles, and improperly sized nozzles or header pipes.
At Kaiser, the header pressure was recorded from a gauge about 10
meters north of midbattery for all units; the accuracy of the gauges
was not requested. Header steam pipes were reported to be 5.1 cm (2 in)
inside diameter and the nozzle size was reported to be 1.4 cm (9/16 in) inside
diameter. The static (between charges) and dynamic (during charging)
pressures were recorded during charging observations.
Table 2 compares average steam pressures with average duration of
emissions for each battery (each battery has its own steam line). The
Table shows a general trend toward shorter emissions as steam pressure
increases, although the data base is small; exceptions include batteries
C and F which do not show good correlation. On an oven-to-oven basis,
there are instances of no correlation between steam pressure and duration
of emissions. For example, ovens 303 and 333 had the highest (65 sec)
and lowest (5.5 sec) emission times for battery E, and both had the same
O
dynamic pressure of 6 kg/cm (85 psi).
Available aspiration steam pressure was lower than that for other
coke batteries observed by the NEIC for 5 of the 7 batteries (batteries
D and F being the exceptions). Studies show that a 4.28 m (14 ft) oven
requires about 62 std m3/min (2,200 scfm) aspiration1. Figure 3, which
is a plot of aspiration capacity and steam pressure at the nozzle,
indicates that approximately 7.7 kg/cm2 (110 psig) is needed at the
nozzle for a double collector main to provide 62 std m3/min aspiration.
At 5.27 to 6.33 kg/cm2 (75 to 90 psig), which is the steam pressure for
most of Kaiser's batteries, aspiration ranges from 47 to 52 std m3/min
(1,650 to 1,850 scfm) for a double collector main battery.
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Table 2
AVERAGE STEAM PRESSURES AND DURATION OF EMISSIONS
Static Dynamic
Battery Pressure Readings Pressure Readings Emissions
„ ,/2 . .. - , 2 _. seconds
No. kg/cm psig No. kg/cm psig > 20%
opacity
A
2
5.03
71.5
2
5.24
74.5
43.6
B
2
5.83
83
3
5.74
81.7
47.4
C
4
6.70
95.3
2
6.19
88
5.5
D
2
8.15
116
2
7.38
105
6.9
E
1
7.24
103
3
6.44
91.6
13.2
F
4
8.95
127.2
6
8.32
118.3
19
G
1
6.33
90
5
6.05
86
29.1
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1300
1200
3/4
1100
9/16
1000
900
1/2
h 800
Nozzle Diameter
CO
700
u
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The above estimates were made with the following variables taken
into consideration. Although Kaiser's ovens are 4.28 m (14 ft) high,
they are not as wide as the ovens that the study is based on and there-
fore would not require as much aspiration. On the other hand, the
steam pressures evaluated were measured at the header. Actual nozzle
pressure, hence aspiration, would be less due to pressure drop in the
lines. Also, the volume of air in the oven which would be displaced
by coal during charging was not taken into consideration and would
require slightly more aspiration.
DOORS
Door Cleaning Practices
Adequate door cleaning before each coking cycle is necessary to
reduce door leaks.3 The door knife edge, refractory and jamb need to
be reasonably clean to allow the door to fit well for sealing. The
knife edges and jambs are especially prone to permitting door leaks if
they are not clean. The door gas channel needs to be reasonably clean
to allow coke gas formed near the door bottom to flow to the top of the
oven. Gas pressures as high as 710 mm of H20 can be present in the
gas channel at the bottom of an oven shortly after charging4. Any
restrictions in the channel to the flow of these gases can contribute
to door leaks.
Kaiser's operating procedure requires regular door cleaning. Every
door is given a routine cleaning each time it is removed. Worker
instructions for a routine cleaning are as follows:
1. Using a short bar, all carbon must be removed from around the
bottom of the jamb.
2. All carbon and loose tar must be removed from the jamb, using
the long bar if necessary.
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3. Gas passage on all doors must be kept open.
4. All loose carbon must be removed from each door.
5. Chuck door sealing edges and chuck door jamb surfaces must be
clean of all carbon and heavy tar.
6. The sill plate must be cleared of all loose material.
7. Loose coke and tar must be pulled off the apron plate using
a hoe.
8. The bench must be kept clean at all times to eliminate trip-
ping hazards.
9. Everyone must understand the difference between: carbon,
which is hard; heavy tar, which is very thick and will ul-
timately become carbon; and the light tar film which forms
on the jamb surfaces. The light tar film is beneficial for
sealing the ovens and should not be removed until it has ac-
cumulated beyond the regular film thickness and has started
to form heavy tar and carbon.
Approximately every fifth door removed is given a special cleaning.
Worker instructions for a special cleaning are:
1. Clean all loose carbon and tar from the door.
2. Using both the long and short bar, clean all carbon and heavy
tar from the jamb face, shaving the carbon buildup on the in-
side of the jamb flush with the jamb surface.
3. Chip carbon from the door sill and the underside of the door
butt plate.
4. Clean all tar from the apron plate, particularly in the area
next to the jamb.
5. Clean the chuck door and chuck door jamb of all carbon and
heavy tar.
6. Spillage must be thrown clear of the sill plate.
7. The pusherman (or benchman on 52 oven schedules) will scrape
tar from top of jamb face immediately after removing the door
and before the push.
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Approximately once per month each door is given a chipping, which
means stripping all hard tar and carbon from the door and knife edge.
Worker instructions for chipping are:
1. Strip all carbon down to the brick and metal on the door and
behind the sealing ring.
2. In all other ways, chipping is the same as special cleaning
mentioned above.
Actual observation of the door cleaning practices revealed some
significant deviations from the required procedures discussed above.
On routine cleaning, the door jambs were seldom cleaned, often de-
posits remained. The gas channels on the upper part of the door were
sometimes nearly blocked and were not cleaned, and chuck doors were
seldom cleaned.
On special cleaning, the upper part of the door jamb and the inside
of the jamb were seldom cleaned. Observations also indicated that
cleaning practices were sometimes not thorough. Instances were re-
corded where carbon deposits remained in gas channels and jambs after
cleaning. Knife edges, however, were normally free of excessive de-
posits.
Door and Jamb Conditions
The condition of the door, especially the knife edge and gas chan-
nel, and the jamb are important to controlling door leaks. Warpage
or other damage to these areas can result in significant leaks. An
adequate supply of spare doors is necessary to replace warped or dam-
aged doors so that they can be repaired.
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Of approximately one hundred doors that were observed during the
inspection, five had knife-edge damage, fifteen had refractory damage,
none had gas channel damage, and no jamb damage was noted. The effect
of recorded door damage was not evident from readings made on door leaks.
Spare Door Availability
Spare door checks indicated 0 to 2 readily available spare doors
per side per operating unit. The need for spare doors is determined
from operating experience, but in any case should be greater than zero.
Collector Main Pressure
During coking, the oven is kept under a slight positive pressure to
prevent outside air from entering. If the oven pressure is higher
than normal (up to 12 mm of M^O) the additional pressure will tend to
increase door, lid, standpipe cap, and other leaks. Table 3 lists
approximate average collector main pressures obtained from chart re-
cordings during the inspection period. These pressures are considered
to be within the normal range.
Door Design
The knife-edge sealing mechanism and the depth and width of the gas
channels are design parameters that could affect door leaks. Based on
limited data from other coke plants, the depth of the gas channel (1.9
cm) on Kaiser's doors is shallow compared to other gas channel depths.
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Table 3
COLLECTOR MAIN PRESSURE
Battery
Coke Side Chart
mm/^O
8:00-16:00
Push Side Chart
mm/^O
8:00-16:00
A
9
10
B
8
8
C
9
9
D
9
8
E
8
8
F
11
10
G
10
9
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Chuck Door Sealing
Chuck doors are usually small metal doors that are especially sus-
ceptible to warping and leaks because they have no refractory lining.
When a chuck door leak becomes significant at Kaiser, a gasket is in-
serted between the chuck door and its jamb. The gasket is replaced
each time the door is opened. Inspection observations indicated that
most gaskets were able to seal chuck door leaks.
LIDS AND STANDPIPES
Luting Practices
Luting lids and standpipe caps can greatly reduce the amount of
leaks from these sources. Kaiser's luting procedure requires the
following:
1. The standpipe lids are luted prior to dropping the charge.
2. The charging hole lids are luted immediately after the charge
has been completed.
3. All charging steam must be left on until the luting operation
has been completed.
4. All charging hole lids and standpipe lids must be luted to
the point that there are no visible smoke emissions.
5. All smoke emissions that are visible within assigned working
areas must be luted and/or reluted immediately. There are
no exceptions to this rule.
Actual observation of lid and standpipe luting practice revealed
that steps 4 and 5 listed above were not adhered to. The percentage of
standpipe caps leaking per operating unit ranged from 3.3% to 21.1% and
averaged 10.6%; the percentage of lids leaking per operating unit
ranged from 0% to 5.2% and averaged 2.9%.
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Physical Condition
Battery topsides (lids, standpipes, and collector mains) in poor
condition due to warping, cracking, holes, etc. contribute to topside
leaks. Inspection of the battery topsides at Kaiser did not indicate
that the equipment condition was a major problem. Some standpipes with
leaking flanges or bases were noted, along with several collector main
leaks. However, the problem appeared to be one of maintenance, not of
design, construction, or materials.
Collector Main Pressure
The effect of collector main pressure on lid and standpipes leaks
was discussed in the section on Doors.
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IV. RECOMMENDATIONS
Because of the limited amount of data with which to establish cor-
relation between operating parameters and emissions, most of the follow-
ing recommendations to reduce visible emissions are based on general
observations and commonly accepted practices throughout the industry.
CHARGING
2
Aspiration steam pressure should be maintained at 7.7 to 8.4 kg/cm
(110 to 120 psi) for each battery.
Goosenecks, caps and nozzles should be cleaned for every oven
charged rather than every fifth oven. Gooseneck cleaning should be
improved; nearly half of the goosenecks observed following cleaning had
carbon buildup of 2.5 to 5 cm. Machine cleaning should be considered.
Channel heights should be at least 30.5 cm (12 in). The installa-
tion of aprons in the larry car coal hoppers should be considered so
that the volumetric settings and, hence, the channel height can be more
closely controlled. In addition, if peak and channel heights cannot be
taken, the angle of repose of the coal should be closely monitored and
adjustments to volumetric settings made to ensure a 30.5-cm-high channel.
Chuck doors should be kept open for the minimum amount of time
(less than 30 seconds) before and after the leveling bar is in the oven
to minimize aspiration loss.
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A proper charging sequence should be maintained. The number 2
hopper should be charged only after hoppers 1 and 3 are empty. In addi
tion, number 2 lid should be replaced before seating to minimize leaks
during the time while cleanup is taking place and before the lids are
finally reseated and luted.
DOORS
Every door and jamb should be cleaned to the specifications of a
"special cleaning" as defined in Kaiser's standard operating procedures
The oven schedules obtained each morning from the Company allowed no
additional time for special cleaning. Therefore, special cleaning
each door, rather than "routine cleaning", should not slow production.
More spare doors should be made available for both coke and push
sides on all batteries. Doors observed in need of repair when removed
should be replaced by a spare door.
LIDS AND STANDPIPES
The standard operating procedure for luting and reluting lids and
caps should be strictly adhered to.
Collector main and standpipe flange leaks should receive greater
attention. They should be luted or otherwise repaired.
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26
REFERENCES
1. Emission Control in Coking Operations by Use of Stage Charging,
Munson, Lewis, Weber, and Brayton, APCA Report Series, Feb. 1976.
2. Coal, Coke, and Coal Chemicals, Wilson and Wells, McGraw Hill,
1951.
3. Federal Register, Vol 41, 46765-46767, Oct. 22, 1976.
4. Study of Concepts for Minimizing Emissions From Coke Oven Door
Seals, Lownie, et al., Battelle Columbus Labs, Ohio (EPA 650275064),
July 1975.
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