EPA-600/2-77-058
February 1977
Environmental Protection Technology Series
SEALING COKE-OVEN CHARGING LIDS, CHUCK
DOORS, AND STANDPIPE ELBOW COVERS:
SURVEY OF CURRENT U.S.
STATE OF THE ART
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environ-
mental Protection Agency, have been grouped into five series. These five broad
categories were established to facilitate further development and application
of environmental technology. Elimination of traditional grouping was con-
sciously planned to foster technology transfer and a maximum interface in
related fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4~ Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL HEALTH EFFECTS
RESEARCH series. This series describes projects and studies relating to the
tolerances of man for unhealthful substances or conditions. This work is gener-
ally assessed from a medical viewpoint, including physiological or psycho-
logical studies. In addition to toxicology and other medical specialities, study
areas include biomedical instrumentation and health research techniques uti-
lizing animals—but always with intended application to human health measures.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
-------
EPA-600/2-77-058
February 1977
SEALING COKE-OVEN
CHARGING LIDS, CHUCK DOORS,
AND STANDPIPE ELBOW COVERS:
SURVEY OF CURRENT U. S. STATE OF THE ART
by
C.E. Mobley, A.O. Hoffman, andH.W. Lownie
Battelle-Columbus Laboratories
505 King Avenue
Columbus, Ohio 43201
Contract No. 68-02-1323, Task 58
ROAPNo. 21AQR-042
Program Element No. 1AB015
EPA Task Officer: Robert C. McCrillis
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
-------
Ml
TABLE OF CONTENTS
Page
INTRODUCTION 1
Location of Coke-Oven Charging Lids, Chuck Doors,
and Standpipe Elbow Covers 2
STATE-OF-THE-ART SURVEY ON SEALING CHARGING LIDS,
CHUCK DOORS, AND STANDPIPE ELBOW COVERS 5
Charging Lids 5
Chuck (Leveler) Door., 7
Standpipe Elbow Covers 12
SUMMARY 12
REFERENCES 14
LIST OF FIGURES
FIGURE 1. SCHEMATIC ILLUSTRATION CROSS-SECTIONAL VIEW
OF A BY-PRODUCT COKE OVEN 3
FIGURE 2. SCHEMATIC ILLUSTRATION OF STANDPIPE SYSTEM 4
FIGURE 3. SCHEMATIC ILLUSTRATION OF CHUCK (LEVELER) DOOR
SEALING SYSTEM 8
FIGURE 4. SCHEMATIC ILLUSTRATION OF A BLOOM ENGINEERING CO.
LEVELER AND PUSHER DOOR ASSEMBLY 10
-------
Introduction
By-product coke ovens have long been recognized as one of the
primary sources of emissions within the steel-plant complex. Numerous
studies and development/implementation programs have been undertaken to
reduce the quantity of emissions associated with the coke-making process.
Understandably, most attention has been directed to the parts or steps of
the coke-production process which are considered the principal sources of
the emissions. Thus, attention has been focused on controlling and/or
eliminating the emissions associated with oven charging, pushing, coke
(2-5)
quenching, and end-closure leakage.
While these are the predominant sources of emissions, other
parts of the coking units may also emit pollutants. Little quantitative
information is presently available as to the underlying causes, quantity,
and temporal duration of these secondary emission sources associated with
the coke ovens.
This study was undertaken to provide the U.S. Environmental
Protection Agency (EPA) a survey of the current state of the art for
sealing coke-oven charging lids, standpipe elbow covers, and chuck doors
within the U.S. coke-making industry.
This survey was conducted as part of the EPA program entitled
"Technical Support for US/USSR Task Force on Abatement of Air Pollution
from the Iron and Steel Industry". The intent of the survey was to establis
the current design and operating methodology relating to the sealing of the
oven charging lids, elbow covers, and chuck doors. The development of data
on the extent and types of emissions associated with these three components
of coke ovens was not part of the program's scope. This study was conducted
over the period of October 15 through October 31, 1976.
Prior to presenting the results of the survey program, it is
advantageous to briefly describe the location and function of the three
coke-oven components considered in this study.
-------
Location of Coke-Oven Charging Lids,
Chuck Doors, and Standpipe Elbow Covers
An illustrative schematic cross-sectional view of a by-product
coke oven is shown in Figure 1. The relative locations of the charging
lids (Circle 1), the chuck door (Circle 2), and the standpipe elbow cover
(Circle 3), are indicated as part of Figure 1. Most U.S. coke ovens have
4 charging holes (and, in turn, 4 charging lids) located across the top
of each oven. A small number of U.S. coke batteries have ovens with
3-charging-hole systems.
The chuck (or leveling) door is the opening in the end-closure
door through which the leveling bar is introduced for leveling the coal
during and after charging to the oven. Each end-closure door on the pusher
side of the oven contains one chuck door near the top of the door (specifically,
at a height matching the coal line of the oven).
To permit the escape of volatile matter driven from the coal
during coking, an opening exists at the top of the oven at either one
or both ends of the coking chamber. Each such opening is fitted with an
offtake pipe known as the standpipe or ascension pipe, which connects the
oven with the gas-collecting main for the battery. Where one gas off-
take is provided, it is through the roof of the oven at one end of the oven,
and where two offtakes are used, there is one at each end of the oven. The
volatiles pass through the ducts in the oven top into a refractory-lined
standpipe which, in turn, is connected to a collecting main through a damper
valve. The standpipe is equipped with a cap valve, or "elbow cover" between
the damper valve and the oven. The piping associated with the volatile
offtake system is generally of a shape similar to a gooseneck, (i.e.,
[/ shaped), with the elbow cover or cap located at or near the top
of the standpipe system. A more detailed schematic illustration of a
standpipe system with its elbow cover is shown in Figure 2.
For the major portion of a coking cycle, these three components
(i.e., charging lids, chuck doors, and standpipe elbow covers) are in place
(i.e., in a closed or sealing position). The charging lids are removed
from the charging holes during the coal charging operation and during
the preceeding decarbonization period. After charging the coal to
-------
j(§tandpipe Elbow Cover)
FIGURE 1. SCHEMATIC ILLUSTRATION CROSS-SECTIONAL VIEW OF A
BY-PRODUCT COKE OVEN
-------
BLUSHING UQ!JQE
SPRAY IMO2ZLES
FIGURE 2. SCHEMATIC ILLUSTRATION OF STANDPIPE SYSTEM
(6)
-------
the oven, the chuck door is opened to allow the introduction of the leveling
bar to remove the peaks resulting from charging. The standpipe elbow cover
is opened to provide access to clean the standpipe (i.e., remove constricting
carbonaceous buildups). The elbow cover is also opened to vent the oven
to the atmosphere. All these components are closed for the duration of the
coking period. If these three components are properly designed, maintained,
and placed, they are expected to provide total seals against the emission of
pollutants to the atmosphere.
With this brief description of the oven charging lids, chuck
doors, and standpipe elbow covers, the current state of the art for sealing
each of these components is presented in the next section. For those
readers desiring more information on these components, a more detailed
description of the location and function of these three components is available
in The Making, Shaping and Treating of Steel.^ '
State-of-The-Art Survey on Sealing Charging Lids,
Chuck Doors, and Standpipe Elbow Covers
The current techniques and methodology for sealing each of the
three components are presented sequentially herein,
Charging Lids
Oven charging lids are typically circular cast iron or steel lids,
16 to 18 inches (40.6 to 45.7 centimeters) in diameter, and 1 to 3 inches
(2.5 to 7.6 centimeters) thick. Most charging lid-frame assemblies are
designed to seal via a conical or tapered (i.e. ,\~ / ), metal-to-metal
contact of lid against frame. Some lids are designed to seal through a
shouldered (i.e. .'-jUIIr3 ) metal-to-metal joint. Both the charging lid and
the frame into which the lid seats may distort during service. The distor-
tion of the lid-frame system is a major factor contributing to the occurrence
of emissions from this component. Also, both the lid and frame seating
surfaces must be periodically cleaned in order to secure an emission-free
operation. While coke-oven designers indicate that the charging-lid-frame
systems should, if properly cleaned and maintained, provide an effective seal
-------
against emissions, most plants use some type of luting material or slurry to
seal the lids after charging. Typically, after the charging lid is replaced
in the charging hole, coal and coke dust lying on the top of the oven are
swept to the vicinity of the lid/frame surface interface to fill any gaps
which may exist. After filling the lid/frame region with carbonaceous
material, luting mud, or slurry is applied to the lid/frame interface on the
top of the oven. On drying, the mud luting or slurry provides an effective
sealant. Good operating practice dictates that the sealing material not be
applied to the metal-metal contact area below the oven top surface. The mud/
slurry used to seal the charging lids should be inexpensive and readily
available with a consistency which can be easily applied to achieve a seal.
It is also important that the dried material break cleanly from the lid/frame
interface when the lid is removed for the next coal charging.
One slurry used by a coke-producing plant to seal its charging
lids consists of a mixture of (1) clean-up materials, such as coke breeze
/
and old mud from the luting of end-closure doors, (2) clay from a local
source, and (3) water. A typical batch of this slurry consists of
one part clay, 2 parts breeze, and 1.8 parts water, by weight. Another
slurry used to seal charging lids in the U.S. consists of 40 percent lime
(CaO), 55 percent alumina (A^O-) and 5 percent silica (Si02) mixed with
water. There are apparently a wide variety of slurry mixtures in use, some
based on clays, some on silica flour, etc.
The use of a mud/slurry to obtain an effective seal does not
alleviate the need for good cleaning practice. Many operators indicate that
dirty lids (i.e., those with a carbonaceous deposit between lid and hole)
are difficult to seal via the application of the mud/slurry. Lid cleaning
is done every coke cycle or on a periodic, regular basis. Also, the lids
may distort in service due to the heating and cooling. As the lids become
increasingly distorted, sealing becomes more difficult and the lids must
be replaced eventually to eliminate eimssions.
Modern coal charging systems frequently contain automatic (magnetic)
lid lifters which oscillate the lids (typically through + 15° of the final
position) as part of the lid seating placement in the charge hole. Such
movement during seating should improve the sealing characteristics of the
lid. It is estimated that the lids are manually placed on more than 90
percent of all the U.S. coke ovens (i.e., less than 10 percent are equipped
-------
with magnetic oscillatory lifters). Thus, the oscillation during lid
seating is not yet a major factor relative to sealing performances in
today1s operations.
With pipeline charging systems, the charging lids are replaced by
valves in the pipeline. These valves are somewhat removed from the oven
top, thereby reducing the problems attendant to obtaining an emission-proof
seal. Oven lids used in conjunction with the pipeline charging systems will
be used only for oven inspection, for decarbonizing the ovens and to vent
excessive pressures. In pipeline charging systems, one lid is designed and
designated to serve as a safety valve to relieve excessive pressure which
may occur in the event of constrictions in the standpipe and/or reduced gas
removal from the oven.
It is anticipated that less emissions will occur from oven lids
used with the pipeline charging systems.
Chuck (Leveler) Door
Chuck-door seals are similar to the seals used on the oven end-
*
closure doors. Typically, the seal is a metal-to-metal seal consisting
of a plain carbon steel, or stainless steel rib or strip attached to the
door, which is pressed against a flat surface portion of the end-closure
door. A representative cross-sectional view of a chuck door (and end-
closure door) seal system is shown in Figure 3. Just as with the end-closure
door seals, the chuck-door-sealing strip design and dimensions, and the
methods of applying loads to the sealing strips to effect a seal, vary x^rith
the designer and builder of the door system. In general, leakage of chuck
doors occurs as a result of the same factors and/or phenomena which cause
end-closure-door leakage. Thus, chuck-door leakage may occur because
(1) the chuck door—end-closure door are not dimensionally stable under
the heating and cooling cycle(s) to which they are exposed, (2) tars and
other carbonaceous materials may accumulate or deposit nonuniformly on the
seating surface and cause high and low contact points, thus causing emissions,
* Current methods for sealing coke-oven end-closure doors are reviex^ed
in Reference 4.
-------
PLAIN CARBON
OR
STAINLESS
STEEL SEAL
STRIP
SLOT IN DOOR
CASTING FOR
SEAL STRIP
COMPRESSION SPRING
LEVELLER
DOOR CASTING
SECTION THROUGH OVEN DOOR AT LEVELLER DOOR
FIGURE 3. SCHEMATIC ILLUSTRATION OF CHUCK (LEVELER) DOOR
SEALING SYSTEM
-------
and (3) the chuck-door-seal elements may not be chemically stable (i.e.,
they may carbonize, oxidize, and/or sulfidize) in the particular service
environment, thereby leading to pitting or other dimensional alterations,
which in turn promote leaking.
For example, the sealing strip and its contact surface may warp
and/or distort such that when one portion of the sealing edge is closed,
an adjacent strip region does not contact the surface of the end-closure door.
Many chuck doors are equipped with compression springs and/or screws
designed to force the sealing strip against the mating flat surface. In
some cases it has been observed that the springs lose their spring character-
istics with time. Others have observed that the screws do not deflect the
strips to achieve a complete seal around the chuck door perimeter.
As with the general end-closure door sealing problem, proper
maintenance and cleaning practices (e.g., removal of the carbonaceous
deposits on the chuck door contact surfaces) appear to reduce the quantity
of emissions from this component.
Chuck door design is an ongoing development. Several companies
have suggested that the door-seal systems of older design were too inflexible
to provide adequate sealing performance. As one example, Bloom Engineering
*
Company has promoted the retrofitting of older, more rigid chuck-door
systems with their stress-relieved, more flexible, dome design leveler-
door unit made of 400-series stainless steel. The basic seal element of
the Bloom chuck-door system is the metal-to-metal contact seal as shown in
Figure 4.
Little quantitative data are available with which to judge the
performance of one type of door or seal system relative to another under
controlled conditions.
When the metal-to-metal contact seal of the chuck door becomes
ineffective as a result of distortion of excessive carbonaceous deposits
on the sealing surface, some operators resort to luting the door or applying
gaskets to effect a seal. Luting materials are made of the same mixtures of
materials as used for the charging lid slurries, but with less water. The
Bloom Engineering Company, Inc., Horning and Carry Roads, Pittsburgh,
Pennsylvania 15236
-------
Latching Mechanism
(Closed Position)
* X * ^ ~ N
\\\\ \\ \
\ , V V N. V N
eveller Door Seat
•Leveller Door
rPusher Door
\N x \
\\ \ xN \ s -
00 SERIES
STAINLESS
STEEL
DOME
/A\\^X \ V^ VVX
/ A VN. s \N \ vN \ _!
N\NN X \X?,
Pusher Door Frame
Oven Buck Stay
Latching Mechanism
(Open Position)
<
\/
FIGURE 4. SCHEMATIC ILLUSTRATION OF A BLOOM ENGINEERING CO.
LEVELER AND PUSHER DOOR ASSEMBLY(8>
-------
11
luting material is either applied to the flat contact surface of the end-
closure door so that the sealing edge becomes encased in the luting or the
material is troweled or laid along the outside of the chuck door, end-
closure contact line. As with the slurry used to seal the charging lids,
the luting material should be inexpensive, readily available, and should be
easily removed/cleaned, from the door on opening.
Some companies employ gaskets as a method of sealing chuck doors
which do not "self-seal". EPA is currently sponsoring a study on the use
of gaskets on coke-oven chuck doors.* The data on chuck-door gasket usage
presented herein, are taken largly from information supplied by TRC—
The Research Corporation. The preliminary general results of the TRC study
are:
"(1) Gaskets are usually employed as a temporary measure
until the chuck door can be repaired.
(2) Chuck door design and state of repair are equally as
important as gasket use for minimizing visible emissions.
(3) Gaskets in use include:
(a) Cardboard
(b) Tarpaper
Aft
(c) Esscolator
AAA
(d) Fiberfrax
(4) Gasket use has been limited, but when they have been used,
AAAA
the manufactured gaskets have been generally, successful
as a temporary control measure".
* Chuck Door Gasket Study, EPA Contract No. 68-01-3154 to TRC -
The Research Corporation of New England, 125 Silas Deane Highway,
Wethersfield, Connecticut 06109, Mr. Joe Hopkins, EPA
** Esscolator Gaskets are a lamination of steel foil and compressible
refractory paper produced and marketed by Essolator Mfg. Co.,
727 Pennsylvania Avenue, Pittsburgh, Pennsylvania 15221
*** Trademark, The Carborundum Company
A*A* Items (c) and (d) of statement (3) above.
-------
12
The general conclusion from TRC's initial survey is that gaskets
have not been used extensively by the industry and therefore experience
with gaskets is limited. Chuck door design and preventative maintenance are
considered better approaches than gaskets to the visible emission problem.
Standpipe Elbow Covers
(2 5)
Several references ' , and personnel of companies contacted
during this study, indicated that emissions/leakage from standpipe elbow
covers is common in many plants. The leakage from standpipe elbow covers is
generally attributed to (1) improper cover positioning, (2) failure to
properly clean the cover-seating areas, or (3) distortion of the cover/seat
system. The elbow cover is designed to seat against the metal standpipe
proper. Thus, the sealing mechanism is by a metal-to-metal contact seal. The
design of the seal varies from designer to designer, with some being simply
a flat surface on the elbow cover mating to a flat surface on the standpipe,
while others use a tapered or conical metal-to-metal seat, and yet others using
a shouldered seat. In general, oven designers indicate that such seals will
not leak or allow emissions if they are properly cleaned and maintained. As
with the charging lids, and chuck doors, when a standpipe elbow cover does
become a noticeable source of emissions, operators will effect a seal by the
application of a luting material, a slurry, or a gasket. The same or similar
luting muds, slurries, or gaskets used to seal the charging lids and chuck
doors are also utilized on the standpipe elbow covers.
While operators recognize that standpipe cover leakage may be a
rather common occurrence, most operators contacted during this survey felt
that cover leakage need not be a significant emission source if the cover
were seated properly and/or the cover-standpipe contact area were cleaned
prior to replacement of the cover.
Summary
The seals associated with coke-oven charging lids, chuck doors, and
standpipe elbow covers are all metal-to-metal contact seals. The charging
lids and standpipe elbow covers are typically flat, tapered, or shouldered
-------
13
surface contacts, whereas the chuck door seals are similar to the end-
closure door seals, i.e., metal strips pressed against a flat metal surface.
Oven designers indicate that all three components should provide an emission-
proof seal, if properly cleaned and maintained. Most coke-plant operators
augment the inherent seal of these components with luting mud, slurries,
and/or gaskets.
-------
14
REFERENCES
(1) Final Technological Report on "A Systems Analysis Study of the
Integrated Iron and Steel Industry", prepared for Division of
Process Control Engineering, National Air Pollution Control Administration,
Department of Health, Education, and Welfare, by Battelle Memorial
Institute (Contract No. PH 22-68-65), May 15, 1969.
(2) Edgar, W. and Muller, J., "The Status of Coke Oven Pollutidn Control",
Ironmaking Proceedings, AIME, 32, 1973, pp 76-84.
(3) Roe, E., "Coke Oven Emission Control Systems". Ironmaking Proceedings,
AIME, J}4, 1975, pp 229-234.
(4) Final Report on "A Study of Concepts for Minimizing Emissions from
Coke-Oven Door Seals", prepared for the U. W. Environmental Protection
Agency, and American Iron and Steel Institute, by Battelle's Columbus
Laboratories, (Contract No. 68-02-1439), March 26, 1975.
^
(5) Voelker, F. C., "A Contemporary Survey of Coke-Oven Air Emissions
Abatement", Iron and Steel Engineer, Vol. 52, No. 2, February, 1975.
(6) The Making, Shaping and Treating of Steel, Ninth Edition, Edited by
H. E. McGannon, United States Steel, 1971.
(7) Muller, J. M. et al., "Gary Coke-Oven Door Development Program",
Paper presented at the Joint Meeting of the Eastern and Western States
Blast Furnace and Coke Oven Association, on October 25, 1974.
(8) Bulletin C-2790, Bloom Engineering Company, Inc., Horning and Carry Roads,
Pittsburgh, Pennsylvania 15236
-------
15
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-77-058
2.
3. RECIPIENT'S ACCESSION-NO.
AND SUBTITLE Sealing Coke-oven Charging Lids,
Chuck Doors, and Standpipe Elbow Covers: Survey
Current U.S. State of the Art
of
5. REPORT DATE
February 1977
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
C.E. Mobley, A.O. Hoffman, and H.W. Lownie
8. PERFORMING ORGANIZATION REPORT NO.
3. PERFORMING ORGANIZATION NAME AND ADDRESS
Battelie-Columbus Laboratories
505 King Avenue
Columbus, Ohio 43201
10. PROGRAM ELEMENT NO.
1AB015; ROAP 21AQR-042
11. CONTRACT/GRANT NO.
68-02-1323, Task 58
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Task Final; 10/76
14. SPONSORING AGENCY CODE
EPA/600/13
is. SUPPLEMENTARY NOTESIERL-RTP task officer for this report is R. McCrillis, Mail Drop
62, 919/549-8411 Ext 2557.
is.ABSTRACT The report gives results of 2i survey of the current U.S. state-of-the-art
approach and methodology for sealing coke-oven charging lids, chuck doors, and
standpipe elbow covers. The study was part of the program, 'Technical Support for
U. S. /USSR Task Force on Abatement of Air Pollution from the Iron and Steel Indus-
try. ' The survey concluded that: (1) seals associated with coke-oven charging lids,
chuck doors, and standpipe elbow covers are all metal-to-metal contact; (2) charging
lids and standpipe elbow covers are typically flat, tapered, or shouldered surface
contacts, but chuck-door seals are similar to end-closure door seals (i.e. , metal
strips pressed against a flat metal surface); (3) oven designers indicate that all three
components should provide an emission-proof seal, if properly cleaned and maintained
and (4) U.S. coke plant operations augment the inherent seal of these components with
luting mud, slurries, and/or gaskets. The study did not develop data relating the
extent and type of emissions from these components.
17.
KEY WORDS AND DOCUMENT ANALYSIS
a.
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
COS AT I Field/Group
Air Pollution
Iron and Steel Industry
Sealing
Coking
Ovens
Air Pollution Control
Stationary Sources
Coke Ovens
Charging Lids
Chuck Doors
Standpipe Elbow Covers
13B
11F
13 H
13A
3. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReportf
Unclassified
21. NO. OF PAGES
18
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
------- |