l!II.-.' _ TECHNIC~AL REPORT

C\ONTROL TECHNOLOGY

FOR WORKER EXPOSURE

TO COKE ClVEN EMISSIONS.

U. S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE

Public Health Service

Center for Disease Cont'ol

Nati')Il~1 Insti~ute for O~.cupational Safety and HeCllti,

',,:;- ar~.

iyt)l .. ,D"",.. '"i

PERSONNEL SERVICES

~·7lnitai

@8tn.tES

Sf££!

~orforation

",800 GR"NT STREET

PITTSBUflGH. PENNSYLVANIA 15230

December 18, 1978

Mr". John W. Sheehy

Chelaic,:ll Engineer

Chemical Agents Cont:col Section

Department of Health, Education,

" and Welfarz

467~ Columbia parkway

Cincinnati, Ohio 45226

Dear Mr. Sheehy:

You have our permission t~ use Figures 4-:>, 4-14, and 4-7.4 as

requ~sted in your December 8. 1978 letter.

Please accompany each Figure with the "Copyright 1971 by United

States Steel C..)rporation" notice.

Yours truly,

9fi/U'{ j)-.6/~~ Jerry D. Brooks, Manager

Educational Services

RDB:atg
MAY 29 198Q

UNIt'ED STATES DEPARTMENT O!= COMMERCE

Na1;lon::;o1 Technical info!"mal:ion Servicl'

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U133098

National Institute fOT Occupational

Safety and Health

Clearinghouse, DTS

Carolyn A. Browning

Room 212

4676 Columbia Parkway

:incinnati, Ohio 45226

Reyourreport: NIOSH-80-114, "Control Technolog)' for Worker Exposure

to Coke Oven Emissions"

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I t?!t~ CJAt:t~ -r JOHN H. ASHLEY:; ,,-- - Input Branch

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FSC/rkb

Form NTIS-63 (Bev 3-78)
CONTROL TECHNOLOGY FOR NOHKER EXPOSURE

TO COKE OVEN EMISSIOUS

John W. Sheehy

u.s. DEPARTMENT OF H~ALTH, EDUCATION, AND WELFARE

Public Health Service

Cen~er for Disease Control

National Institute for Occupational Safety and Health

Division of Physical Sciences and Engineering

Cincinnati, Ohio 45226

March 1980

For jUlie by Ihr Supt!dnt~:ld~nt or Documcnt8. u.S. Govemrnenl

Print 10K ornC'c. WOl'lhinp;ton. D.C. 20402
DISCLAIMER

Mention of company names or products does not constitute

endorsement by the National Institute for Occupat.ional Safety

and Health

DHEW (NIOSH, Publication No. 80-114

;;
ABSTRACT

Numerous studies have shown "coal tar" products increase the risk

of skin and lung cancer. One study showed top side coke oven

workers had a lung mortality rate 10 times that of all steel

workers. Another study showed that men employed at coke ovens for

more than five years showed a mortality rate 3.5 times the

expected rate. In view of this significant health hazard to

thousands of coke oven workers a NIOSH in-house study to assess

coke ovan control technology was performed.

Control technology for coke ovens was assessed through visits to

seven United States coke oven plants with state-of-the-art

control ~e~hnology and by a review of current coke oven control

technology literature. Each control method is briefly described

and the effectiveness of important engineering and work practice

controls is presented. The report discusses, separately,

controls for charging emissions, pushing emissions, door emission~ and top side leaks.

Charging emission controls include larry car stage chargi~g,

fixed duct secondary collector~ and pipeline charging. More than

a dozen pushing emission control metho1s are discussed in the

repert. Door emissions control technology suer as new doc-r

sealing techniques, guillotine doo~s and exhaust hoods are d~scribed and evaluated, and enclosed filtered air systems are

discussed.

Significant conclusions are: Greater effort should be devoted to

the development of control tectnology for door emissions, and

pipeline charging appears to have advantages over larry car stage charging in reducing worker eKposure. Important recommendations

include: Develop controls for 6-meter metal-to-metal doors,

evaluate well ventilated sheds, and evaluate pipeline charging in

terms of worker exposure.

iii
CONTENTS

• . iii

. . vi

1

.J..

. 2

. • 3

10

21

30

38

40

44

Abstract . . • . •

Acknowledgments. . . .. ••..

Introduction . . . • . • . . . . • . . • . • .

Methodology • . • • . • • . . . . . • .

Coke Oven Industry Overview • . . . • •

Charging Emission Control Technology. . Pushing Emissions Control Technology •• Controls for Continuous Emissions . • .

Worker Environment . . . . • . . • • . . • • . . . . . .

Conclusions and Recommendations • . • • . . . • . . . .

References • . . . . . . . . . . . . . . . • • • • . . .

v
ACKNOWLEDGMENTS

We wish to thank the steel compar.ies and merchant coke plants for

their cooperation and assist~nce in this study. We also wish to

thank Mr. Andrew Trenholm i Environmental Protection Agency, Mr.

John Barker, Armco Steel, and Messrs. Dennis O'Brien, Jer0ffie

Flesch, and Robert Hughes, NIOSH, who provided technicnl guidance

in the preparation of this manuscript.

vi
INTRODUCTION

Numerous studies have shown the use of "coal tar" products

increases the risk of skin and lung cancer. One study showed top

side coke oven workers employed for more than 5 years had a lung mortality rate 10 times that of all steel workers. Another study

showed that men employed at coke ovens for more than 5 years

showed a mortality rate 3.5 times the expected rate(l) (2).

In view bf the significant health hazards to thousands of coke

oven workers, the NIOSH Control Technology Research Branch

undertook a study to assess coke control technology. The results

of the study are documented in this report.

The report summarizes coke oven control technology, including

engineering controls and work practices, developed in thE United

States and in other countries. Each control rn~thod is briefly described and, if known, the current status of each contr01 is

described. This report discusses, separately, controls for

charging emissions, pushing emissions, deor emissions, and top

side leaks. Enclosed filtered air cabs and pulpits are also

described.

The information in the report was obtained thrGugh five visits to

seven United States coke oven plants with state-of-the-art

control technology, and through a revi~\~ of the current coke oven

control technology literature.
METHODOLOGY

Articles from the lit~r&ture as well as basic textbooks on coke

oven constructioc and operation have been reviewed. Opinions

from the United Steel Workers, control equipment manufacturers,

industrial health personnel r and approximately 40 coke plant

operators were solicited for recommendations of candidate plants

for study. Plants were selected on the basis of the variety of

control techniques in use, the degree of control, and the

availability of existing sampling data.

One-tc two-·day surveys of sevee coke plan~s, including producecs

of both roundry and blast f~rnace coke, were conducted to obtain

generdl plant data (size, age, controls), to observe engineering

and work practice control methods, and to review existing plant

exposure data. This report discusses the information gatbered

during the surveys and literature review. A wide range of

engineering controls and work practices ar~ identified, ana

effectiveness of these controls is di~cussed in the report.

2
COKE OVEN INDUSTRY OVERVIEW

Metallurgical coke is made by the destructive distillation or

carbonization of bituminous coal. The distillation is done by

baking the coal in ovens to achieve a uniform "skin temperature"

of 1900 to 2000 0 F for 16 to 20 hours. The result of th~

distillation is a "cellular, porous compound which is

heterogenous in both physical and chemical properties," known as

coke (3) •

There are several uses for coke. About 92 percent of the coke is

usen as a reducing agent and fuel in the blast f.~rnaces in

ferrous and nonferrous metals production. Five percent is uSed

as a cupola fuel in foundry operations and three percent is used

in other industries(4}.

The largest producer of coke in the United States is the stee~

industry with over 90 percent of total coke prod~ction. Eight

percen~ is produced by foundry plants (4) .

COKE OVEN DESCRIPTION

There are two main types of coke ovens: The beehive and the

by-?roduct. The scope of this study is limited to only

by-proJuct coke ovens, so a description of the beehive oven is

emitted.

As of 1974, there were 65 by-product coke oven plants with a

total of 13,490 ovens. The predominant design of these coke

ovens are the Koppers, Koppers-Becker, and Willputte Ovens ~hich

constitute about 97 percent of all the by-product ovens. Figure 1

shows a simplified diagram of these ovens. As shown, the basic

difference between the ovens is in the method of firing the

ovens (3) •

A single coke oven consists of a coking chalnber Clnd a heating

chamber. The cokin~ chamber is generally from 30 to 42,6 f8et it"\.

length, from 6 to 20 feet in height, and 12 to 22 inches in

width. A series of 10 to 100 coke ovens form a battery. In the

battery, the coking chambers are alternated with the heating

chambers (3) .

The coal is charged into the coking chambers from the top of the

oven. The coal is charged by one of two methods: Larry car Or

closed charging system. In a closed system, coal is conveyed

directly into the chambers by pipeline or chain conveyor.

Charging by larry car requires three steps: 1) Coal is discharged

into the hoppers on the larry car from a central bunker; 2) the

larry car moves by rail to a position over the chamber to be

charged; and 3) the coal is charged into the chamber from the

lany car.

3
Figure 1. Schematic representation of the differences

in firing methods employed in the three most common

types of coke ovens. Individual flues are not shown.

The firing procedures shown are for a ~ingle phase

of heating which is reversed at the end of a specified

period. (Copyright 1971 by United States Steel

Corpora tion. ) (Used with permi 55 ion)

4
Except for preheated coal, the coal must be leveled in the

coking chambers. This is accomplished by passing a leveler bar

through a door on one side of the chamber across the top of the

chamber as shown in Figure 2. Preheated coal is self-leveling.

The next step after charging and leveling is to seal the coking

chamber. This is accomplished either by placing lids on the

chamber charging hole$ and luting around the lids for larry car

charging, or by closing a valve for pipeline charging.

In the coking process, by-products from the coking chamber are

drawn off through a collection system consisting of horizontal

collecting main (or mains) and a gooseneck standpipe. A typical

system is shown in Figure 3. In some cases the collection

system is equipped with a steam aspiration system which is used

to facillt~te the,withdrawal of by-products from the coking

chamber during charging and lEveling.

Once the coal is coked, the doors on the sides of the coke oven

are removed. A pusher machine (on the push side) operates a ram

which pushes the coke through the oven to the coke side, as

shown in Figure 2. The hot coke passes through a "coke guide U

into a rail m0up.ted ~uench car. The coke laden quench car moves

to a "quench tower" where it is cooled with, water. The quench

car subsequently takes quenched coke to the coke wharf. At the

battery, the doors are replaced and the oven is re2died for the

coal charging.

EMISSIONS

'rhe approximate amounts of by-products obtained by coking 1 ton

of coal in the by-product process are:

Blast Furnace Coke .•..•.•... 1,200 to 1,400 lbs.

Coke Breeze. . . . • • . • . ,100 to 200 lbs.

Coke Oven Gas •.•. , ..••••.•9.500 to 11,500 cu.ft.

Tar . . .•............8 to 12 gals.

Ammonium Sulfate. . . • • • . • • .• • 20 to 28 Ibs.

Ammonia Liquor .....•....•.. 2.5 to 4 gals.

Light Oil.. • ••.••.•.•..2.5 to 4 gals,

The coke oven gas consists of hydrogen, metnane, ethane, carbon

monoxide, carbon dioxide, ethylen2, propylene, butylene,

acetylene, hydrogen sulfide, ammonia, oxygen, and nitrogen. The

tar is the source of pyridine, tar acids, napthalene, creosote

oil, and coal-tar pitch. Benzene, xylene, toluene, and solvent

napthas are the components of the light oil(3).

The major emission sources on coka ovens inclu~e: Leaks around

lids alld doors on tne top and sides, charging emissions, pushing

emissions, and €missj,ons during go?S~neck cleaning.

5
CHARGING, LEVELING AND PUSHING OPERATIONS

IN ONE COI(ING CYCLE OF A BY -PRODUCT COKE OVEN

SEPARATE~ CHARGING

l.ARRY .~_ PUSHER

"i:[ll,':rJ!rfC- JL. ~,~ ... I _ CH4RGING U =g

~~_ C_~~=J[~ _ A. THE CHARGING l.ARRY. WITH HOPPERS OONTAINING MEASURED AMOUNTS OF COAL. IS IN P'SI·

TlON OVER CHARGING HOLES FROM WHICH COVERS HAVE BEEN REMOVED. THE PUSHER HAS

BEEN MOVED INTO POSITION.

B. THE COAl. FROM THE l.ARR)" HOPPERS HAS uROPPED IrlTe THE OVEN CHAMBER, FORMING

PEAKEO PILES.

m ~""OO"" f

.\l r) -1 Ir--- "

- coAl.i"'n ... ~- • .. r,--,-r----lf--- ]1 I I

r I i' _..:: ~--=__ I --'Ci __ V_ _ _

C. TH;; LEVEl.ING DOOR AT THE TOP OF THE OVEN DOOR ON THE rUSHER SIDE HAS BEEN OPENED,

ANi:! THE l.EVEl.lNG BAR ON THE PUSHER HAS BEEN MOVEO BACK AND FORTH ACROSS THE

PEAKED CCAl. Pll.ES TO l.EVEl. THEM. THE BAR NEXT IS WITHOIlAWN FROM THE OVEN,THE LEVELINr. DOOR AND C~IARGING HOLES ARE Cl.DSED. AND THE COK.NO OPERATION BEGINS.

COKE GUIDE~I -Y,' __ :T. - ),~ -'" -------'--

QUENCHING • ~b~' .'>;:'", =-==- CAR'~[J,i'.F}~'1'!: f! !:_.__~~

_J::.::.i:L _fT_ -" -~~ - _ n COKINC OF THE COAl. ;')RI~INAl.l.Y CHARGED INfO THE OVEN HAS BEEN CDMPl.ETED (IN ABOUT

18 HOURS) AND THE OVEN IS REAO>Y TO BE 'PUSHEO: THIi OVEN O?o;-~ ARE REMOVED FROM

EACH EN!), AND THE PUSHER, COKE r,UIDE AND QUENCHING CAR APE MOVEn INTQ roSIrIQN.

'n - ~RAM OF PUSHER

:'-;- j. ...r-~..:r-- ~'~"';~ ." 4MiQ4 ~--- ... $..~. , -

y" '- ,,------,.- -1-

I'J I I~ '. -=!. J

.L....ll._ I __ .-.L...L__ L_ _ _ _ _ _ E. THE RAM CoF THE PUSHER AOVANCt..5 TO PUSH THE INCANDESC~~T COKE OUT OF THE QVEN.

THROUGH THE COKE GUIDE AND INTQ THE QUENCHING CAR.

Figure 2. Schematic representation of the.seq~ence of o~erations

in charoing. leveling, and pushlng 10 one Coklng cycle of a by~product coke oven. (Copyrirht 1971 by United

Steel Corporation.) (Used with permission)

6
SPP.AY

NOLZLE~

STANDPIPE ELBOW

" CLEl·\NEFl FROM .....C!-lARGINI3 CAR

SPRAY .

NOZZLE ~~

Figure 3. Wilputte arrangement of stalidp;pe, liquid sealed

damper valve, and collecting main. (Courtesy,

Wil putte Coke Oven Di v., All; ed Chen/; ca1 Corp.)

(Used with permission)

7
CHARGING EMISSION CONTROL TECBNOLOGY

Barnes et al. reported that for a well ope~ated coke plant in

1970, without special emission control equipment, charging

emissions represented about 60 percent of total coke oven rlan~

emissions (5). Charging emissions have been greatly reduced in

the 1370's, and no longer represent such a large portion of

emissions. Even so, research and development continues in an

effort to further reduce charging emissions. In this stUdy, lor 2-day surveys we=e made to seven coke oven plants. Charging

emission control systems were observed at each of these plants.

The major charging emissions control systems are presented in

Table 1.

Charging emissions result from the discharge of coal to coke

ovens. As the coal is introduced into the hot coke oven, there

is a sudden displacement of air along with some initial

combustion of the fresh coal. The resulting smoke and gases are

forced out of ti.e oven through any opening or cracks. There are

two primary methods of controlling smoke and gases: 1) Prevent

gases from escaping and 2) clean the gases before discharging

them into the environment. Generally, there are two systems for

charging ovens. Each system is discussed separately below.

LARRY CAR STAGE CHARGING

Two techniques for charging coal are larry car charging and

closed

LARRY CAR CHARGING

Stage Charging (operating technique) Stag~ Charging with Automatic Lid Openirg,

Closing and MUdding

Larry Car Mounted Wet Scrubbers

Sequential Charging (operating technique)

AISI/EPA Car

Still-Erin Car

Fixed Duct Secondary Collectors

PREHEATED COAL CHARGING SYSTEMS

Pipeline Coal Charging

Conveyor Coal Charging Simcar Two-Stage Preheated Coal 2harging

Table 1. Charging Emissions Controls

charging systems. (In a closed system, coal is conveyed ipta

the oven by pipeline or by chain conveyor.) La£ry car charging

is the ~ost common method of charging coal into the oven.

Control of emissions from larry car charging requires a

8
combination of engineer~ng and work practice controls. Larry

car charging emission controls include~ 1) Stage charging (or

sequential charging), 2) double collection mains, 3) jumper

pipes, 4) gooseneck qleaning, 5) nigh pressure aspiration and 6)

scrubber larry car.

A number of control systems for larry car charging emissions

were observe~ in the study. At a fully int~grated steel mill

with a single coke oven battery, the coal is charged by a

modified larry car equipped with an enclosed air conditioned

cab, a scre~ feeder, a ju~per pipe, and volumetric ~ontrols for

regulating the amount of coal in each larry car hopper. A

standpipe cleaner with expanding blades is located on the

"bridge" of the larry car. The larry car operator operates the

stand pipe cleaner from the "bridge." This eliminates a

hazardous task normally performed by the lidman.

The coal is charged using the "stage charging" operating

technique. The outer hoppers are discharged first, followed by

the inside hoppe~. Once the coal is charged, the lids are put

in place and the lidman luteE the lids by hand which forms a

seal around the lid. It is most important that the lids be

carefully luted and, if necessary, luted several times to

prevent emissions from the oven.

Visual observations and NIOSH sampling results during the survey

show top side emissions, including charging emi.ssions, to be

very low. The abatement equipment such as the modified larry

car and the operating technique of stage charging appear to be

very effective in minimizing charging emissions. Careful luting

of the top side lids following coal charging appeared to

eliminate lid leaks with one or two exceptions.

The meteorological conditions at the plant appeared to lower

worker exposures to charging emissions. The wind carriec away

much of the smoke and gases emanating from the coke Oven battery.

A second coke oven plant produces blast furnac~ coke for sale,

ana has an annual production capacity of 2 million tons of

coke. The plant has three coke oven batteries. All the coke

ovens are charged by larry car. The two nearer batteries, I and

2, have a larry car equipped for stage charging and automatic

lid opening, closing, and mudding. The automatic lid opening,

closing, and mudding device works well mechanically; hawever,

the automatic mudder does not completely seal the lids, 50

automatic mUdding must be f~llowed by hand luting. The

automatic lid closing and mudding device benefits the lidman by

eliminating most of lhe lid emissions prior to hand luting.

Oven drafting i~ accomplished by use of double collection

9
mains. Goosenecks and standpipes are cleaned and maintained by

dec3rbonization cycle, routine inspection, and cleaning ~y

hand. Twice per year, the goosenecks are hydraulically c~2~Dea

with 4,000 to 10,000 psi pressure. The larry car on the older

number 3 battery has been retrofitted for stage charging tnrougn

three charging holes instea8 of the usual four. The larry Car

does not have a screw feeder or an automatic lid opener and

mudder. Despite the use of the stage charging control

technique,visible colored emissions were observed during

chrtrging en battery 3. The cause of the emissions appears to be

inadequate oven d~afting and leaks in the dropsleeve.

A third plant inspected is a full integrated steel plant with

S,OOO employees, lncluding 300 coke oven workers. The plant has

seven coke Oven batteries. Batteries 1 to 5 are 25 to 30 years

old, while batteries 6 and 7 are ap?roximately 20 years old.

Each batter.y consists of approximately 45 coke ovens. Oven

dimensions are 14 inches by 13 feet by 40 feet.

The coke ovens are charged by larry cars designed for stage

charging. Each larry car is equipped with stainless steel lined

hoppers, vibrators, and poqo sticks (to break the coal bridge

that develops on hoppers). Oven drafting consists of double

coJ.lection mains. Top side lids are hand luted. Standpipe and

gooseneck are cleaned manually. The plant does not use high

pressure water to clean goosenecks because of the safety problem

in controlling the direction of the water jets.

Visual observations showed emissions from charging were very

low. The larry cars with stage charging appeared to be well

adapted to the batteries. Stage charging at this plant appears

to be an effective centrol technology for reducing charging

emissions.

A fourth plant that was surveyed employed more than 8,000

workers of which 400 are coke oven workers. Two side-by-siGe

batteries were observed. Oven dimensions of the two batteries

are 18 inches wide, 11 feet high, and 38 feet long.

Coke oven charging consists of larry car stage charging. The

larry car is designed with stainless steel-lined hoppers,

volumetric controls, air and sticks for breaking the coal arch,

jumper pipes on the larry car, and drop sleeves around the

discharge openings. The gooseneck is manually cleaned, and lids

and standpipes are manually luted.

As a result of stage charging and adequate aspiration

(drafting), charging emissions appeared very low on the two

10
batteries. Again, larry car stage charging appears to be a

satisfactory cCutrol method for charging e~issions. It should

be noted that, while jumper pipes may provide adequate

aspiration, double ~ollection mains are the preferable control

techr:101ogy.

Another plant observed produces foundry coke for sale. It

employs approximately 150 workers. The batteries are Kopper's

design. CO~lng time is typically 27 to 30 haurs, which is much

longer than the 16 to 20 hours typical for metallu,gical coking.

Coke ovens are charged by larry car" stage charging through five

charging ports with 150 psi steam asp~ration. The larry car is

equipped with stainless steel hoppers, pneumatic vibrators, and

drop boot sleeves. Gooseneck stendpipes are inspected after

each push by inserting a 7-inch diameter plate into the

gooseneck pipe. Th€ goosenecks are cleaned by using a pneumatic

chipping tool.

COke oven charging methods at this plant differ somewhat from

charging systems previously discussed. Ther(~ are five charging

ports for each cokt: oven where normally tt:~n~ are tllre,~ or four

charging ports. Steam aspiration of 150 pEi exceeds the

pressure found in most coke oven drafting systems. Stage

charging with 150 psi steam aspiration (with properly sized

nozzle) may pote~tially i~prove control of charging emissions.

In addition to the larry car charging control systems observed

in this study, there a~e a number of other United States and

foreign control techniques for redu~ing charging emissions. For

the most part, these controls have been tried and rejected or

are of recent clevelopment.

Larry mounted wet scrubbers have operated in Japan, England,

Germany, the Netherlands, and in America. In

the larry mounted wet scrubber, gGses from charging are

combusted and drawn through wet scrubbers. The scrubbed gases

are exhausted by fan(s). There are two common types of gas

scrubbers: Rotary and venturi-type(5) .

Battelle observed wet scrubbers at 12 different plants. None of

the scrubber cars managed a completely smokeless charge. Many

operators complained about the scrubber car and indicated it

required extensive maintenance. Battelle summarized its

findings regarding wet scrubber. cars and made the following

comments: "1) They are relatively costly, complex., a.nd sensitive

to adjustment, 2) scrubber cars create a substantial problem in

the disposal of polluted exhaust waters, 3) overall operational

history indicates progressively severe maintenance problems and

11
increasing breakdown rates, and 4) a state-of-the-art "ret

scrubber in good condition and properly adjusted, operated in

connection with strong aspiration, can eliminate all but a

little of charging smoke about 90 percent of the time" (5) .

"Sequential charging" is an operating technique to control

charging emissions. Sequential charging, as defined in the

Uni ted States, refers to the dis,,:harge of coal from all larry

car hoppers into the OVlm in the following manner: The outer

hoppers, numbers I and 4 (for ovens with four lids), are

discharged first, follo~led 9 to 12 seconds later by hopper

number 2 and a few secon~s lat~r by hopper numbe~ 3. The

essential difference between sequential and stage charging is

that once sequential charging begins it must continue until all

the hoppers Rre empty (5). U. S. Steel found sequential

charging blocked the tunnel head, allowing smoke to escape

through dropsleeves and hoppers. It was concluded that

sequential charging was an unsatisfactory method for controlling

chargi.ng emissions(6).

The American Iron and Steel Institute and Environmental

Protection Agency developed a larry car charging emission

control method called the AISI/EPA charging system and tested it

at the Jones and Laughlin Steel Plant in Pittsburgh. The system

attempts to control emissions by closi~g off all gas escape

rOQtes, increasing injector stearn pressure, and

by collecting gases in a single collection main. Gas

escape routes a=e the chuck doors, which are closed off by a

seal around the leveler bar, and coal hoppers, which are sealed

by a butterfly valve. The AISI/EPA charging system also has

automatic lid lifters, a standpipe gooseneck cleaner, and a

communication and sensing system(7).

As of 1975, the AlSI/EPA charging system had been tested at J

and L Steel (Pittsburgh), and was b~ing added to two other

American coke plants. Battelle investigators, based on

observations in 1973, did not consider the AISI/EPA car as a

completely satisfactory charging emission contr01 technique (5) •

A larry car charging system, similar to the AISI/EPA car, is the

still-ERIN system widely used in Germany. An American version

of the Still-ERIN car has been built at a new American coke oven

plant. The American Still-ERIN car is equipped with mating

dropsleeves, slidegates, screw feeders f and automatic lid

mechanism. The concept of the Still-ERIN system is to closely

fit the hopper extension (charging telescope) to the charging

hole, control coal flow by an oscillating butterfly valv~, close

off hoppers before emissions escape, and steam aspirate gases

into a single collection main. The American coke oven battery

12
with modified Still-ERIN car includes double collection malns to

improve oven drafting.

Battelle ranked Still-ERIN fourth as a control technology tor

charging emissions behind closed charging (pipeline or Redler

conveyor), staged charging, and the best versions of wet

scrubbing(5). Graham and Kirk found results, to date, on the

still-ERIN car "not very encouraging" (8) •

Fixed duct secondary collectors in conjunction with larry car

wet scrubbers have been used extensively to control chaLging

emissions in Japan. In the fixed-duct system, charging

emissions are exhausted, through a larry car scrubber, then

ttrough a stationary collection main to a fixed scrubber, and

then to a fan for discharge to the atmosphere (9) . Above ea~h

oven is a connection port to the stationary collection main.

Battelle concluded the fixed duct secondary collector was not

potentially effecitive, relative to incremental cost(5).

PREHEATED COAL CHARGING SYSTEMS

A pipelir,e charging system was observed at a fUlly integrated

steel cOIllpany employing 23, 000 \'lOrke:cs, including 1,300 coke

oven workers. The plant has six coke oven batteries; however,

only the one battery, with pipeline charging, was observed. The

pipeline charging system (Coaltek System) feeds preheated coal

under pressD~e to the coke ovens(lO). The system is a closed

system which should theoretically, eliminate charging

emissions. The Coaltek System allows the use of more plentiful

but lower quality Illinois coals without sacrificing quality and

reduces coking time. Major startup problems with the Coaltek Syste~ included leaks and piugged distribution lines. Most of

these startup problems have been solved but some remain.

More research is needed to evaluate the performance of the

Coaltek System as a control technology for charging emissions.

Such research could be done at one of the coke oven plants .hich

have installed the Coaltek Systems. Semet-Solvay Division,

Allied Chemical Corporation, Detroit, Michigan; Alabama

By-products Corporation, Tarrant City, Alabama; Inland Steel

Company, East Chicago, Indiana; and J and L Steel, Aliquippa,

pennsylvania, have Coaltek preheating and pipeline charging

installations (11) (12) •

The Bergbau-Forscheing Precarbon System, developed by Didier-Kellogg~ is another method for charging preheated coal

(2000C) to the coke oven. Like th~ Coaltek System, the

Bergbau-Forscheing System eliminates the larry car. Unlike the

Coaltek Syst~m, the Bergbau-Forscheing System transports

13
preheated coal from a weigh hopper to the ovens by a Redler-type

con7eyor and chutes connected to the charge holes. The system

is in the early stages of development and appears promising (8) •

A third version of preheated coal charging is England's

Simon-Carves (Simcar). The unit preheats wet coal to 2400C in

two stages using a specially designed car for charging. Simcar

was developed through research sponsored by British Steel

Corporation; even so, British Steel Corporation hes decided to

use the Coaltek System instead of Simcar at two of its

pI an ts (13) •

PUSHING EMISSIONS CONTROL TECHNOLOGY

Pushing emissions result when hot coke (~arbonized coal) is

forced out of the long narrow coke oven into th~ quench (hot)

car, Emissions continue as the quench car moves to the quench

tower.

According to the 1970 Battelle study, pushing emissions were

second to Charging as the most serious source of emissions (14) •

Improved charging controls have increased the relative

seriousness of pushing emissions, especially ~missions from

"green" pushes. A ~green" push is incompletely carbonized coke

that produces a tremendous greenish-black emi~sions plume.

Pushing emission controls have a two-fold purpose: 1) To reduce

relatively low emissions from normal high quality coke and 2) to

reduce serious emission resulting from a "gr,.:en" push.

Pushing emission controls include:

Sheds

Canopy Hoods

PECT

Ericar

Fog Spray The Whi te Gi ant

(Der Weisse Riese)

Haleon (Interlake)

Osterfeld Car

Weirton (Roppers Car)

Envirotect (Chemieo)

Granite City Steel One

Spot Car

Mitsubishi Fixed Duct

Koppers Fixed Du~t

Genoa-Corigliano

Calderon Super Quencher

In this study, NIOSH investigators observed pushing control

systems at the seven plants visited. Sheds were used at two

plants. One plant installed a shed over the battery coke side

primarily to prevent air pollution from pushing emissions

anddoor leakage. The sh~d is approximately 40 feet high and is

open to a height of 10 feet along the entire bottom. Pushing

and door emissions rise up the side of the battery into a large

duct at the top of the shed, and exhaust to the air cleaning

14
system. The shed appears to slightly increase e~posure of coke

side workers (under shed), while slightly reducing the exposure

of top side worl(ers. The shed was designed with open ends,

partially open sides, and a high rate of exhaust ventilation.

This design, along with strong ventilation, greatly reduces coal

tar oitch volatile (CTPV) concentrations from the high levels

that-could easily occur under the shed. Data from the plant

show the highest CTPV concentration under the shed was three

times the standard of 0.150 rng/~3.

The shed at the second plant also encloses the battery coke

side. This shed is 360 feet long with a volume under the shed of

200,000 cubic feet. Two 200,000 cfm fans exhaust air from the

shed. The exhaust fans were down for repair during our visit,

and a result we observed was poor visibility under the shed and

heavy fallout of particulate malter resulting from pushing the

oven.

One coke producer tas developed a method for controlling pushing

emissions called the pushi~g Emission Control Technology (PECT)

system. It is designed primarily to control "green" pushes.

PEeT differs from a quench car or a one-spot hot car. Details

of the PECT system are presently confidential, since attempts

are being made to have PECT patented. Observations by the NIOSE

investigators showed PEeT effectively controlled pushing

emissions. According to a plant official, operator acceptance

of the PECT is total. It appears the PEeT system may also have

cost advantages over other pUShing emission control technologies.

The Ericar is a patented system for controlling pushing

emissions. The Ericar is an ordinary quench car with a movable

steel curtain that encloses the hot coke as it is pushed into

the quench car. The hot coke gases exhaust through flexible

piping to a scrubber car that rides on track behind the quench

car. The scrubber cleans the hot gas~s before dizcharging them

to the atmosphere. We observed that the Ericar effectively

controlled "non-green" pushing emissions.

No special pUShing emicaion controls are used at several coke

oven plants visited. The hot coke is pushed into an ordinary

quench car and quickly moved to the quench tower for quenching.

Despite the lack of special pushing emission controls, the

pushing emissions were slight at these plants. Data provided by

one plant with no special pushing control and our observations

indicate that pUShing emissions make a smull contribution to

overall worker exposure to CTPV.

h "fog spray" system for controlling pushing emissions was

observed at a coke oven plant producing merchant coke for sale.

15
As coke is pushed into the quench car, the fog spray system is

activatec and water is sprayed o~ the hot coke. The fog spray

produced seme steam but no black smoke. ~he spray nozzles of

the fog spray system are located on the quench car, and the pump

ana a SaO-gallon water tank are located on the locomotive. The

fog spray system uses about 250 gallons of water per push. The

coke oven manager explained the key to a successful fog spray

system is the design and installation of the pumps and spray

nozzles.

The literature contains a number of additiona: pushing emission

control systems which are described below.

~Der Weisse Riese" (the White Giant) is a bench-mounted,

self-contained hood for controlling pushing emissions. The hood

covers the hot car dur.ing the entire push. ThG White Gia~t

features a draft and scrubbing system without moving parts. A

Battelle: team was favorably imp:::essed by t~e Whi te Giant bl~callse

of its good collection and scrubbing of emissions. The

scrubbers produce a clean exhaust and do not simply dilute the

emissions. The disadvantage of the White Giant is its large,

heavy, and costly design. The steaming and water supply system

are difficult to construct and operate. There is also a problem

with corrosion of the rotor venturis(5) (15).

Interlake, Inc. tested a proictype coke oven pushing emission

control car in 1973-74. The Interlake (Hulcon) car consists of

three units: rl 20-ton electric locomotive with an operator

control panel, a 40-feet long quench car with a fume capture

hood; and a tr.a:,ler control car with pumping, heating, cleaning,

and demisting equipment.

The trailer car also contains a 2,400-gallo~ service water tank.

The Halcon car operates by passing hot, pressurized water

through jet-type scrubbers to clean the smoke and gases

collected in the hooded quench cnr. The scrubbed gases pass

through a demister and are emitted to 'he atmosphere (16) .

As a result of tests conducted in 1973. the prototype Halcon car

was modified to inclUde a canopy-type hood over the ~ntire width

of the car. In addition, sheeting was hung alo~g the battery

side of th~ quench car parallel to the hood. The improved hood

design, along with increased suction, has resulted in

satisfactory performance of the emission control car and capture

cO: emission fumes. A remaining major disadvantage of the

emission car is the likelihood of freezeup during winter

operations (16) •

The Osterfeld (or Firma Carl Still) emission contral system

consists ~f two cars: A hot coke transport car (container car)

16
and a continuous wet quencher. The container car captures

pollutants from the pl1sh~d coke and cOiltinuously cleans the bot

coke as it is transportee to the quenchicg station. The wet

quencher gradually quenches the coke, thus eliminating any

sudden plumes of steam and water vapor.

The container car is designed with a b{n in the lower part of

the car. The bin has a capacity for 33 sbort tons of cake.

Above the bin is a space covered by a hood to contain

emissions. In the hood is an opening to match the ope~ing of

the coke guide. As coke enters the container car, smoke and

gases are exhausted to the wet scrubber. After the coke is

pushed, a light door COvers the hooa opening where the coke

entered. The container car then moves to the quencher area

while discharging the coke to the continuous wet quencher. Both

the container and wet quencher cars are planned for automatic

operation, but, d~ring testing, an operator was assigned to each

car(17).

Test results at the Oste~field plant in Germany show that

pushing emissions are aaequately scrubbed juring normal

operationr however, strongly "green pushes" cannot be

statisfactor1ly cleaned. A 50 percent increase in scrubbing

capacity was recommended for the container car. An interesting

feature of the Osterfeld System is that, despite a let of rough

handling, the abrasion of the coke was minimal (17), According

to Battelle investigators, the Osterfela car (St.ill) represents

an advance in the state of the art for controlling pushing

emissions (5) "

National Steel Corporation in Weirton, West Virginia, dBveloped

a one-spot hot car and continuous quencher. !t is similar in

concept to the Interlake (Halcon) and Osterfeld systems. As

coke is pushed into the weirton hot car; a stainless steel

curtain encloses the hot coke and gases. pushing emissions are

drafted through a refractory-line duct to the gas cleaning

system on a second railcar. Graham et a1., in 1975, found the

weirton (Kopper) system to have exces3ive oper.ation and

maintenance problems (8). Traubert of National steel stated in

1977, that for the most pa~t, the enclosed (Weirton) quench car

has been successful, but the gas cleaning car would be more

effective with some design changes. One such change incluaed is

stainle;;;s steel piping to replace r:dla steel piping(lB) .

Chemica (Envirotech) has developed an enclosed quench car for

controlling pushing emissions. In the Chemica syst~m, hot coke

is guided into the quench car and emissions are drawn through

tbe hoo~ into an attached control car. The emission gases are

17
scrubbed and discharged to the atmosphere as the hot car moves

to the quench tower. Chemico system consists of a three-sided

hood attached to the quench car and a wall attached to the coke

guide that forms a fourth side. Two hot water scrubbers dLaw

th~ smoke from the open oven and the hood at rates up to 90,000

scfre. Chemica sold one of their hooded quench cars to J and L

Steel in 1976(19).

In an effort to develop a suitable enclosed pushing and quench

system, Granite City Steel came up with their own one-spot

enclosed coke pushing control system. The Granite City system

consists of a "coke guide" enclosure, a coke receiving car, and

a connection between the coke guide Anclosure and the coke

r.eceiver car. The coke guide has a telescoping hood which meets

the movable hood section of the coke receiver cer. The receiver

car is an enclosed box-like structure, except for an opening for

coke to enter ~nd a connection to the gas cleaning car. pushing

emissions evacuated from the coke L€ceiving car are cleaned by

high energy variable throat venturi scrubbers located on the gas

cleaning car. The Granite City gas cleaning car eliminates the

locomotive from the pushing control system. According to

Granite City researchers, field tests show the one-spot enclosed

pushing control system is simple to operate and does not

in~rease cycle time between pushes(20).

Mitsubishi Chemical Ind:.lstries (MCI) Ltd., Tokyo, Japan, has

developed a pushing control system, the

Mitsubishi-Amagaski-Shinwa smokeless pushing technology. The

system consists of a movable hood coverifi9 the quench car, fixed

ducts, and a wet scrubber and fan. The wet scrubber, fans, and

water supply system are stationary while the hood is attached to

and moves with the coke guide. The hood connects with one of a

series of suction ducts located above each oven. As coke is

pushed, emissions flow from the hOud through the sucti.on ducts

to the wet scrubber and are discharged to the atmosphere. A

critical feature of the Mcr pushing emission control system

(fixed duct) is a tight con~ection between the hood and the

suction ducts. A poor connecticn re~ults in the escape of

almost all pushing emissions to the atmosphere. According to

Battelle, the successfully performing Mcr system at the Takogawa

plant in Japan had drafts of 140,000 cfm.

Mcr pushing emission control technology (fixed duct) eliminates

the bench-mounted machinery for cleaning pushing emissions.

Such extra machinery can lead to safety and structural problems

on the battery. The MCr pushing control technology has been

added to a nUillber of existing coke oven facilities in

Japan(S) (15) (21).

18
Koppers fixed duct pushing control technology is similar to the

MCl. The Koppers system consists of a movable hood over the ~oke

0uide and part of the quench car, a fixed duct alon~ and

parallel to the battery, and gas cleaning equipment. The

Koppers system differs from ~CI in the type of hood and in fint

points of connecting the hocd to the fixed ducts. A Kopper

fixed duct pushing control system has been installed at Ford's

Dearborn coke oven plant. Similar to Mcr system, the Kopper

system at Ford will requir.;; an estimated draft of l>!O,OOO cfm

for its tall, new battery. However, actDal draft requirements

depend on the type of scrubbing system used(B).

Some additional pushing control systems of lesser interest are

the Gen.oa-Corigliano designed by Heinrich Koppers of Germany (8)

and the Calderon Super Quencher in the United states (22) •

Pushing emissions can sometimes be controlleJ by ;:epairi119 ovens

and by improving work practices. Emissions can be reduced by

repairing end flues, decreasing coal volumes, and slowing the

coking rate. Poor operation such as overflowing ovens Or

improper coal blending can also increase pUShing emissions(23).

In newer, well-operated and maintained coke oven plants, "green

pushes" may be relatively rare. In such cases it may be best to

design pUEhing emission controls for typical emissions rather

than for an occasional "green push."

CONTROLS FOR CONTINUOUS EMISSIONS

TOP SIDE LEAKS

Top side leaks come primarily from chorging hole lids,

standpipes, and goosenecks. Leaks from charging hole lids range

from short wisps to Gontinuous leaks. Generally, charging hole

lids are hand luted immediately after the coal is charged.

Standpipe leaks are often continuous and are controlled by hand

luting, b~t, as the standpipe sheet metal deteriorates over the

years, hand luting is no longer sufficient to stop leaks. Event~ally the top side steel m~st be replaced. Gooseneck leaks

are continuous and are controlled by hand luting.

Top side chRrging hole lids were generally sealed by hand

luting. It was observed that emissions from the :Lids ranged from

negligible on one battery to several lid leaks on the worst ba~tery. Enforced work practlces appeared to be the key to

minimizing leaks from charging hole lids. A second factor is

the type of coke produced since the plant ~ith the fewest top side leaks produced fcundry coke.
One plant the NIOSH team observed uses automatic mudding

equipment attached to the larry car to seal charging hole lids.

The automatic mudding machine seals most of the groove around

the lid; however, it is still necessary to manually lute the

small gaps left by the automatic mudding machine. The automatic

mudder provides a major benefit in that i.t reduces the lidman's

exposure by partially seali~~ the lid before the lidman has to

hand lute it.

Where top ~ide steel is in good condi.tion, frequent inspecticn

and hand luting will satisfactorily control standpipe dnd

gooseneck leaks. If top side steel is in poor condition, hand

luting will most likely be inadequate, and the top side steel

must be replaced. At one plant with side-by-side batteries, a

battery with relatively new top side steel (less than 10 years

old) had very few top side leaks, while several older batteries

(20 tv 30 years old) had numerous standpipe and gooseneck

leaks. It was apparent that ~he aging and deteri.oration of the

top side steel had a major. effect on the top side emissions.

significant top si.de emissions can result where charging hole

lids fail to seal properly because the lids have been distorted

by high temperature. In such cases, the lids must be replaced.

Leaks can occur when lids are not regularly cleaned and the lid

fails to seal properly(9l (23) •

Because of the importance of work practices in controlling top

side continuous emissions, one coke oven plant has developed a

system where inspectors regularly check the coke oven battery

for visible emissions. The inspectors are in a separate branch

from the regular operating crew to increase their objectivity.

DOOR LEAKS

Because of improved charging methods and better control of

pushed emissions, more and more attention has been directed to

controlling door leaks. From the standpoint of worker exposure,

door leaks are of primary importance. Door leaks from a single

oven can last an hour or two following the charge, or can last

through the entire coking period up to 16 hours. Door emissions

rise up and contaminate battery top side workers as well as the

coke and push side workers. Most coke oven batteries have

metal-to-rnetal self-sealing doors on the coke side and the push

side. In general, leakage from metal-to-metal doors is a

serious emission problem at most coke oven plants. At several

plants, sheds are used to prevent door emissions from entering

the atmosphere. A shed, even when well

20
ventilated, presents two problems to the worker: 1) The shed

encloses the door emissions and may increase work,::r exposure and

2) the shed hides the emissions so there is a tendency to delay

repairs to leaky doors. Some worker's under the shed have

protection of the filtered air conditioned cab: however, coke

side benchman must work under the shed outside the air

conditioned cab. Despite a well-ventilated shed, door emissions

should be reduced to the maximum extent possible to protect the

coke side benchrnan. The shed does have the apparent advantage

of reducing the exposure of top side workers to door emissions.

As discussed earlier, one 0: the plants observed in this study

has a series of side-by-side batteries of various ages. All the

batteries have 4-meter, metal-to-metal self-sealing doors. The

older bat~eries (25 to 35 years old) have extensive door leaks

while the newer batteries (less than 20 years old) typically

have few door leaks. One 30-year old battery, recently rebuilt,

including the oven ends, had very few door leaks. The age of

the ovens, particularly the oven ends and the age of the doors,

appear to be the major factor in door emissions. Along with the

age factor, wear and tear caused by excessive heat stresses

accelerates door emission problems. Operating errors are often

the cause of excessive heat stress.

Large, 6-meter metaJ.-to-metal doors are found more and 1T.;Ji.€- at

coke oven plants. At one plant we observed several 6-meter

doors which leaked severely due to warpage. As industry COI1VI2~ts to larger 6-meter, metal-to-J;letal doors the problem of

door leakage will increase. Par this reason, additional

research is re~ommended to improve the design of the larger

doors to minimize warpage and reduce emissions. One plant we

surveyed has tested Japan~se IKIO doors and the Caulderon

automatic mudding technique Eor sealing doors. The IKIO doors

appear promising. Tests on the Calderon technique show problems

with pressurizing the sealing material for injection into the

groove between the door and door jambs (see page 36).

Normally, chuck doors--small doors that open for the leveler

bar--are closed by the door machine, however, at one plant a

wrench is used to open and close the chuck door. This'practice

ensures a tighter chuck door seal and thereby reduces door

emissions.

Another method available for controlling noor emissions is to

hand lute coke oven doors. At one plant with hand luted doors,

we observed very few door leaks and a very clean plant overall.

The plant manager stated this was due to careful luting ot doors

and strictly enforced work practices. The door emissions may

have been easier to central because foundry coke was produced.

21
Guillotine doors are rarely found at coke oven plants although

they have certain advantages. The doors can be raised or

lowered to any desir.ed height above the bench. This allows the

benchman to raise the door I or 2 feet, shovel loose coal into

the oven, and then lower and close the oven door. Loose, smokey

coal can be cleaned up with only slight emissions from the:

oven. The disadvantage of guillotine doors is that they require

hand luting, and it is impractical to add guillotine doors tc

existing coke oven batteries.

Push side controls used to control door emissions include a

shroud over the leveler bar and an exhaust hood above each push

side door. The shroud captures the coal dust the leveler bar

picks up during withdrawal from the oven. The exhaust hood is

used to capture door emissions on the push side. The operator

looks for door leaks and, when he spots one, he activates the

exhaust hood above that particular coke oven door. From the

hood, the emissions are exhausted by a central fan to the air.

pollution equipment. Up to four hoods can be exhausted

simultaneously. Because installation was not complete, we were

unable to observe the exhaust hood system duting our visit. It

is recommended that this exhaust hood door emission control

system be evaluated further.

An incentive program for controlling coke oven door emissions is

being used at one steel plant. According to the coke oven plant

manager, the incentive program has had some limited success in

reducing emissions. Because of the possibility that incentive

programs may lower door emissions, it is recommended that

results of the incentive program be documented.

Graham and Kirk believe that good operation and maintenance

practices are the key to contr.olling coke oven door emissions.

Self-sealing doors and frames must be properly scraped and

cleaned. Improperly cleaned doors will end up leaking. For

new, taller ovens, dooe and frame-cleaning machines are

recommended (8) .

Jones and Laughlin Steel Corporation has very recently developed

an improved metal-to-metal self-sealing door. The improved door

design should reduce bowing and hourglassing. Bow is defined as

"curvature of the jamb into or out of the vertical plar,e due to

thermal and mechanical forces." Hourglassing is "a tendency for

the long sides of a jamb to close together due to temperature

differentials." Excessive bowing and hourglassing prevent

adequate door sealing and must be kept within tolerable

limits(24).

22
Barchfeld et al. state that the improved J and L designed door

minimizes both bowing and hourglassing. The improved design

consists of a vented coke oven door plug, spring loaded

knife-edge S-seal using a NiCuTi material, a special seal pan to

hold the s-type seal, door/seal stops to control door

deflection, guides to position the door for repeatabl~ seal

positioning on the jamb, and a removable seal to reduce

door./seal replacement costs. As a result of 4 months of tests,

door emissions were low enough to meet a local government

requirement that no more than 10 percent of the coke oven doors

leak (24) •

J and L is also testing a soft seal to be used as gasket

material for the end doors. Two materials, graphite fib~r and

asbestos fiber, have been tested. Early results show that the

graphite began to fail after several months of use. The

asbestos gasket continued to function well over a much longer

period (24).

Apother technique to reduce emissions from self-sealing doors

was developed by Caldercn Automation, Inc. with this

technique, a material with bloating properties is injected into

a groove between the door and the coor jamb. A sealing ring is

constructed inside along the perimeter of the door and forms a

groove that receives the new sealing maierial. This groove

takes the place of the sealing edge on typical metal-to-metal

doors. The sealing material must be cleaned off after every

push. Fresh sealing material is then injected before tL~ door

~s cloHed. The Calderon sealing technique can be applied to

chuck doors as well as 6-meter doors. Injecting sealing

material in smaller chuck doors is fairly simple, requiring only

one inj ection port: how'?ver, larger doors require at least four

injection pc,rts (.22).

Operating techniques can also be used to help control door

emissions. One technique considered is to decrease oven back

pressure; but, if improperly applied, this technique can damalJe

oven brickwork (9) (23). Coke oven plants can further improve

door emissions' control by having backup door machine equipment

and spare parts OP hand to minimize interruptions to

operations (9) (15).

Battelle investigators summarized door emission control

technology in stating door sealing technology and practice is

still more art than science' heavily dependent on the attitude

of the bench crew and ripe for intensive studies and

e~perimants. Battelle also stated that firm conclusions r~garding control technology for door leakage could not be

made (5) .

23
Since the Battelle recommendations, EPA has funded several

research studies on control technology for coke oven door

emissions. A July 1975 EPA Report, "Study of Concepts for

Minimizing Emission from Coke Oven Door Seals" (EPA

650/2/75/064), describes door sealing techniques available. EPA

has recently funded a study to review control technology for

coke oven doors(25).

WORKER ENVIRONMENT

Coke oven worker exposure can be reduced by providing filtered

air cabs, standby pulpits, and lunchrooms. In this stu~y, we

observed operators of larry cars equipped with an enclosed air

conditioned cab, coke guide/door machine operators under a shed

in enclosed air conditioned cabs, quench car operators uader a

shed in an enclosed air conditioned cab, and push car orerators

in enclosed air conditioned cabs were observed. It was apparent that filtered air cabs were suitable for workers who could stay

inside the cabs. It was observed that the pusherman and the

coke side door cleaner did stay in the cab while the larry car

operator frequently left his cab to perform duties such as

operating the mechanical gooseneck cleaners. The effectiveness

of enclosed air condi tioned cabs depends pr imar ily on how mue;}

time the operator spends in the cab. Before selecting a

filtered air cab as a control, the percentage of time the

operator spends in the cab should be quantified. We also

observed an enclosed filtered air conditioned lunchroom near the

battery at one plant. The lunchroom uses air filters made by

"James Campb~ll Smith." According to tests at this plant, the

best filters for coke oven application are made by two

companies: "James Campbell Smith" and "Lintern."

The Mine Safety Appliance (MBA) Research Center, under contract

to NIOBE, has tested a filtered air (air purifying) unit in a

OPFICE FOOTNOTE: Information presented at Air Pollution Control

Association Conference on Control of Air Emissions from Coke

Plants, April 17-19, 1979, pittsburgh, Pennsylvania:

1. Door extractors have been found to damage the knife edge

resulting in extensive door emissions;

2. NiCuTi material is superior to stainless steel ~s a knife

edge material;and

3. Reducing the diameter of standpipe caps about 3/4-inch

results in a better seal between the cap and the standpipe

casting.

24
coke oven atmos~here. The unit consists of an MBA ultra aire

HEPA filter, a catalytic oxidizer, and a charcoal bed. The

filter was tested by mounting it in a larry car cab. Results

showed the air purifying unit significantly reduced CO, total

hydrocarbon, total sulfur, total particulate, and NO/N02' MSA

recommended the elimination of the catalyst bed because CO

levels on the coke oven were already low. MSA also recommended

that the filter be scaled up to full size and tested over a

period of approximately 1 year (26) .

Enclosed filtered air cabs, standby pulpits, and lunchrooms can

be effective controls for reducing worke! exposure to coke oven

emissions. But to be effective, the enclosed rooms or cabs

should be tightly constructed and have properly designed and

installed air filters. Finally, enclosed filtered air rooms and

~abs are eff~Gtive only if the worker stays in the room or cab.

Filtered air. lunchrooms may not be effective where smoking is

permitted in the lunchroom. A research project to evaluate

filters for enclosed filterp-d air roo~s in the coke oven

environment is recommended.

CONCLUSIONS AND RECOMMENDATIONS

CONCI,USIONS

1. In order of priority, major sources of coke oven emission

sources are (1) doors, (2) top side leaks, (3) charging

emissions, (4) pushing emissions, and (5) coal shoveling

practices.

2. A major technological breakthrough is required to

significantly improve emissions control of state of the art

larry car charging technology.

3. The advantages of pipeline charging are reduced top side

emi.ssions and removal of the larry car operator and lidman from

the exposure aLea on the battery top side. Disadvantages

include start up problems, high capital investment, and lack of

data on the effect of pipeline charging on the ~xposure of the

benchman and maintenance workers.

4. For new coke oven batteries with even heating flues,

adequace coking time, and consistent cycling, "green" pushes

should be rare and the overall impact of pushing emissions on

worker exposure should be relatively small.

5. Top side leakS from charging hole lids, standpipes, and

goosenecks are best controlled by good work practices such as

careful hand luting. Automatic mndding techniques are available

25
but must be followed by hand luting. Incentive programs to

encourage good work practices have had some limited succe=z,

Major standripp. and gooseneck ~eaks should be controlled by

~eplacing top side steel.

6. Sheds over the batter.y coke side have the apparent advantage

of reducing top side Norker exposure and the apparent

disadvantage of increasing coke side worker exposure, especially

to the bencbman.

7. The age of the oven ends and doors along with the wear and

tear caused by excessive heat stress is the major cause of

emissions from state-of-the-art metal-to-metal self-sealing

doors. The taller coke oven doors are susceptible to greater

warpage and thus greater emissions.

8. The effectiveness of control technology will vary from one

coke oven battery to another. The type of battery, meteorology,

battery age, and environmental goals must be considered before

recommending a particular control. Meteorological conditions

such as wind speed and directi0n greatly affect environmental

concentrations on th~ battery.

RECOMMENDATIONS

1. Coke oven emission ,;::ontrol technology research should

emphasize controlling door emissions. EPA has recently funded a

stuay to improve self-sealing doors to control door emissiuns.

Research should be expanded to include luted doors, guillotine

doors, and foreign coke oven door technology.

2. Research is needed to evaluate techniques for reducing

warpage in the large. 6-meter metal-to-metal self-sealing ~oors.

New door technology such as Japanese IKIO doors and new typ0S of

gaskets and sealing mater ial should be employed as d001:S al,e

reconstructed.

3. Well-ventilated sheds appear to increase exposure of workers

under the shed. The evaluation of a well designed and well

ventilated shed is needed to determine if and to what extent

sheds increase worker exposure. New coke side sheds should not

be built until more data developed on the exposure of the coke

side benchman workin~ under the shed.

4. The effectiveness of exhaust hood use above push side doors

should be evaluated.

5. The unique stage charging and aspiration system (discussed

on page 15-16) appears to be an improved method of controlling

charging emissions. This system should be evaluated further.

26
6. Preheated coal charging system (both pipeline and. (both

pipeline and chain conveyor) reduces overall worker exposur~

because it eliminates the larryman and lidman. Therefore,

preheated coal charging is r~commended for new coke oven

batteries provided: (l) The system does not increase the

exposure of other workers and (2) startup problems can be

minimized.

7. The percentage of coke oveL worker exposure due ~o pushing

emissions should be determined and the results used to

developpriorities for application of coke oven control

technology.

8. Research is needed to determine criteria for filter media

used in lunchroom' standby pUlpits, larry cars, and pusher and

door machine cabs.

9. A time study to determine the percentage of time the larry

car operator spends in/out of the larry car shoulG he yerformed

at several coke oven plants.

10. Meteorological conditions should be considered when

evaluating the effectiveness of emission control methods.

11. Graham and Kirk (7) suggest the gradual development and

application of control technology has benefited the coking

industry in the United Kingdom. We feel this approach is

appropriate for development of coke oven control technology in

the United States.

12. In coke oven emission control technology research, EPA

should consider the effect of control technology on worker

exposure.

REFERENCES

1. Lloyd, J.W., 1971. Long-te~m MortaJity study of

Steelworkers V.--Respiratory Cancer in Coke Plant Workers. J.

Occup Med. 13:53-68.

2. Redmond, C.K., A. Ciocco, J.W. Lloyd, and H.W. Rush. 1972.

Long-term Mortality study of Steelworker--VI. Mortality from

Mal.ignant N~op1asms Among Coke Oven Workers. J. Occup Med

14:621-9.

3. Making, Sh3ping and Treating of Steel. 1971. United States

Steel Corporation, Pittsburg, pp 1420.

4. Exposure to Coke Oven Emissions. 1976. OSHA/DOL. Federal

Register. Friday, October 22:41(206): pp 46742-90.

27
5. Barnes, T.M., H. W. Lownie, Jr., ana J. Varga. 1975. Control

of Coke Oven Emissions. Ironmaking and steelmaking (Quarterly).

2(3): pp 157-87.

6. Munson, J.G., Jr. 1974. Stage Charging Reduce~ Air

Emissions. Enviro. Sci. and Technol. December 8(13):1062-4.

7. Kf~rtcher, L.F. and B. Lineky. 1974. Economics oi Coke Oven

Charging Controls. Journal of the Air Pollut. Control Assoc.

August 24 (8): pp 765-71.

8. Graham, J.P. and B.P. Kirk. 1975. Problems of Coke Oven Air

Pollution Control. Engineering Aspects of Pollution Control.

Met. Ind. Engr. 174:pp 82-100.

9. Voelker, F.C. 1975. A Contemporary Survey of Coke Oven Air

Emissions Abatement. Iron and Steel Eng. February: 52: pp 57- 64.

10. Inland Steel. 1974. Congressional Staff Tour. Indiana

II.9.rbor vJorks. November.

11. Davis, R.F., Jr. 1976. Coa1teck 3ystem-pipeline Charging

Coke Ovens. Ironmaking Proc. Metal Soc. AIME. (Am. Inst. for Mech.

Engin.) 35:pp 479-86. '.

12. Improving Coke Oven Operation with Pipeline Charging of

Preheated Coal. 1976. Ind. Heat. June:43:FP 8-14.

13. Coke Oven Controls: Complex, Costly and Controversial.

1975. Chern. Week. November 11:117(22) :28-9.

14. Plaks, N. 1974. The EPA program of R&D for the Control of

Cokemaking Emissions. Ironmaking Proc. Metal Soc. AIME. 33: pp

109-20.

15. Standidge, J.A. 1975. Collection of Emissions from a Coke

Oven Proc. 22nd Ontario Industrial Waste Conference.

June: 22: 177-86.

16. Rodwick, T.E. 1975. StRrt Up and Testing of Coke Oven

Emission Control Car. Ironmaldng Proc. ;·'ieta11. Soc. AIME.

34: 235-41.

17. price, J.G., T.A. Berg, and J. Stratman. 1974. Coke Oven

Pushing Emission Control and Continuous Wet Coke Quenching.

Ironmaking ~roc. Metall. Soc. AIME. 33:220-32.

18. Traubert, R.M. 1977. Weirton Steel Div.--Brown's Island

Coke plant. Iron and Steel Enq. 54(1) :61-4.

28
19. Enclosed Coke Quench Cars Gain Ground AS Method of Cleaning

Oven Push EmiGsons. 1976. 33 Maga~ine. October 14(lO):pp 38-40.

20. Burroughs, J.D., J. G. Manda, and D.F. Cairns. 1976.

Application of Enclosed Coke Pushing Emission Controls at

Granite City Steel. Proc. of the Air Pollution Control Assoc.

Portland, Oregon, Ju~e:69(76-l24): pp 1-10.

21. Kitasaka, M. 1973. Hitsubishi Smokeless Operation

Technology. Ironmaking Proc. AIME. 32:96-108.

22. Calderon, A. 1977. Controlling Emissions from Coke Ovens.

Iron and Steel Eng. 54(8) :42-6.

23. Edgar, W.O. and J.M. Muller, 1973. Thp. Status of Coke Oven

Pollution Cont~ol. Ironmaking Proc. Metall. Soc. AIME. 32:

76-84.

24. Barchfeld, F.J., I. Gerding, and J.M. Stall. 1978, New

Developments of J and L Drastically Cut Coke Oven Door Emi~sions. Metal Producing. May:16(5}:43-6.

25. Personal Communications. EPA. July 28.

26. Rodgers, S.J. and F. Roehlich. 1971. Evaluation of Air

Purifying Device in a Coke Oven Atmosphere. NIOSH. MSA Research

Cor.poration, Evans City, Pennsylvani.a. HSM-99-73-51, November

15: 19 pages.

29 " us. GO"-ERNMENT PRl~TlNG 'lFFICE' 1980 ~6 57~ 147/5847