United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S7-83-046  Dec. 1983
Project  Summary
Preliminary Environmental
Assessment  on  Formcoke
Cokemaking  Process

D. W. Coy, C. C. Allen, and B.  H. Carpenter
  A preliminary environmental evalua-
 tion and assessment of formcoking has
 been made. The work is based on readily
 available literature sources, a plant
 visit,  formcoke plant  proposal and
 feasibility study data, and discussions
 with engineers and operators involved
 with formcoking. Material balances,
 calculations, and engineering judge-
 ment have been used to convert existing
 data and information into a form that
 can be used to compare environmental
 discharges between formcoking and
 conventional by-product coking. The
 results of those comparisons are pre-
 sented. The lack of  adequate environ-
 mental data on formcoking is noted
  This Project Summary was developed
 by  EPA's Industrial Environmental
 Research Laboratory, Research Triangle
 Park. NC. to announce key findings of
 the research project that is fully
 documented in a separate report of the
 same title (see Project Report ordering
 information at back).

 Introduction
  This  report, prepared in response to a
 request from the Department of Energy
 (DOE),  is a preliminary  environmental
 assessment of formcokemaking. It was
 prompted by a proposal from Inland Steel
 to DOE, soliciting government-funded
 assistance for the design and construc-
 tion of a new formcoke plant. The depth of
 the assessment was  limited by the time
 available to complete the work, and
 insufficient time to do any sampling and
 analytical work. The reported conclusions
 are based on data existing when the study
 began.  Material balances, calculations,
and engineering judgement were used to
convert existing data into a form that
could be used to compare environmental
discharges between formcoking and
conventional coking.
  After completion of this report, DOE
recommended that Congress provide
initial  incremental  funding for detailed
design of the Inland Steel formcoke plant.
While initial funding was approved in
Congressional  committee action,  the
project never received funding considera-
tion before the  full House or Senate.
Inland officially withdrew its proposal in
1981.

Summary
  A preliminary environmental evaluation
and assessment of formcoking has been
made. The work is based primarily on
readily available literature sources; a visit
to the FMC Corporation formcoking plant
in Kemmerer,  WY; data available in
Inland's proposal; data from a feasibility
study  of the proposed plant by Davy-
McKee Corporation; and discussions with
various engineers and operators involved
with formcoking.
  The FMC formcoke plant consists of a
coal preparation section for crushing and
sizing incoming coal, a fluid-bed pyrolysis
section to distill volatile matter and
produce a char, and a briquetting and
coking section to shape and finish the
product. The fluid-bed pyrolysis section
receives coal crushed to minus 4 mesh.
The initial fluidized bed, the catalyzer,
drys  the coal at 149C and partially
oxidizes the coal to reduce agglomerating
properties. The  conditioned coal then
proceeds to the carbonizer  where it is

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heated to 480C to break the coal into tar,
char, gas, and water.  The partially
devolatilized char then is processed in the
calciner at 815C to release remaining
volatiles  and  produce the solid reactive
calcinate.
  After cooling, the  calcinate is mixed
with dehydrated tar and pressed into
briquettes. The briquettes are cured in an
oven at 232C. The cured briquettes are
then coked in a shaft kiln at temperatures
above 800C.
  The fluidizing gas in the  pyrolysis
section at FMC is air. Waste gas produced
in this section has a relatively low heating
value,  5.6 MJ/m3  (150 Btu/ft3). The
proposed Inland plant may operate with
air also,  or alternatively it may  operate
with a fluidizing  gas  enriched with
oxygen  and  steam  to  produce a by-
product gas with higher heating value,
13.0 MJ/m3 (350 Btu/ft3).
  The existing FMC plant was examined
to identify the waste streams leaving the
plant and the pollutant levels in  those
strems.   Because of the limited time
available to complete the project, it was
necessary to  depend on pollutant data
available from test work previously
completed. These available data were not
comprehensive; as a result there were
many data gaps.
  The proposed plant description  in the
Inland  proposal  was compared  to the
existing plant. Differences in the process
equipment and pollution control facilities
were examined. In particular, the proposed
plant would have been about four times
larger than the existing plant, and been
processing an  Illinois (instead of  a
Wyoming) coal. With  Illinois coal the
process would not have produced enough
tar for binder. Supplementary tar would
have had to  be processed and added.
Inland  planned to design the plant  to
operate in either an  air mode similar to
FMC or  an oxygen/steam mode that
would  have produced a  higher  heating
value by-product gas stream than at FMC.
In either mode the gas  would  have been
recovered for other plant uses.
  In the gas recovery  process more
efficient paniculate removal was expected
in the Inland plant than is achieved at the
FMC plant. Since gas is not desulfurized
at FMC, whereas a Stretford system was
proposed  for the  Inland plant, SO*
emissions from the proposed plant would
have been much lower. The FMC plant
discharges wastewater to  a  holding
evaporation pond.  The proposed  Inland
facility final wastewater would have been
treated  in a  publicly owned treatment
plant; pretreatment  in the form  of
ammonia  and cyanide stripping was
planned,  with  the  recycled wastewater
stream cooled by noncontact  water
streams.
  The  adequacy of proposed  pollution
controls for the proposed Inland installa-
tion was also studied. (Note that the final
plant design was  not available, and  the
proposed equipment was little more than
conceptual.) Plans for controlling particu-
lates  and S0> offer the  potential  for
compliance with  proper specifications
and  selection of  design  parameters.
Present NOx regulations appear to affect
none of the proposed plant  sources.
Ammonia  and cyanide incineration,
however, was  expected to  produce more
NOx  than would  be allowed  from  the
smallest source regulated  in Indiana.
Ammonia recovery could be practiced to
reduce NOx emissions. No air pollution
standards for polycyclic organics currently
exist,  and no data were available to
analyze quantities of potential organic
emissions from formcoking.
  With respect to potential discharges
from the proposed Inland  plant,  waste-
water samples were requested from the
FMC plant, but they were not received in
time for analysis  and  inclusion in  the
report. In qualitative terms many of the
components present  in conventional
coking wastewater were expected to be
present in formcoking  wastewater,  but
quantities may be different. Since
specific wastewater treatment equipmenl
has not been selected, an assessment of
the potential for  compliance with pre-
treatment standards  has not been pos-
sible. Also, plans for solid waste handling
were  not defined at that  time,  again
preventing an assessment of the potential
for compliance.
  Finally,  estimated  environmental dis-
charges from formcoking were compared
with those  estimated for conventional
coking. Table 1 summarizes the results of
the comparisons. No direct measurement
of polycyclic  organic  matter  (POM)
emissions was available from formcoking
for comparison with conventional coking.
Worker exposures to benzene-soluble
particulates  have  been measured  at the
FMC plant. In general the FMC measure-
ments show  lower  worker exposures
than have been found  in conventional
coke plants. This  comparison  suggests
that POM emissions may also be lower
for formcoking.
  Not shown in the  numerical compari-
sons  is  the expected greater  ease of
maintaining control  of  air  pollution for
formcoking as compared to conventional
coking. Control of air pollution from the
batch conventional coking process (par-
ticularly hazardous organic pollutants) is
highly dependent  on work  practice and
also tends to deteriorate with coke battery
age as a result of battery dimensional
Table 1.    Comparison of Environmental Discharges  Conventional Versus Formcoking
Environmental
discharge
Particulates
SO,
NO,
from NH3
from other combustion
Wastewater







Sludge and solid residues



POM fas indicated by B(a)P)
Occupational exposure to
benzene solubles
Conventional coking
kg/ Ma coke
0.7-7.5"
2.2

13C

550-1,460
(Including
by-product
recovery)




38"



0.004

150-5OOug/m3
Formcoking
kg/Mq coke
1.1"
2.2

4-14c'a

630- J. 400
Air mode

1.410-2.210
steam/ Oz mode
(Including
by-product
recovery)
29.8'
Air mode
24.7'
steam/Oz mode
No data

50-161 ug/rrf
"Low value, for a well controlled battery for all paniculate sources, is an ideal case.
^Conservative estimate; could be decreased if necessary.
cZero if recovered instead of incinerated.
aThere are indications that the lower-carbonization-temperature formcokeprocess will favor lower
 formation of ammonia.
eIncludes coke breeze (~ 36 kg/Mg) much of which is used as a low value fuel rather than as coke.
'Does not consider possible reuse of formcoke sludges.

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changes. These factors are not expected to
play as big a role in air pollution control
for the continuous formcoking process.
   For normal operations, paniculate
emissions are expected to be about the
same  for  formcoking  as for a well
controlled  coke oven  battery. A well
controlled battery for all paniculate
sources  is an ideal  case that may be
difficult to achieve because of the batch
nature of the process. SOX emissions are
expected to be about equivalent. Since
ammonia is usually  not incinerated for
conventional coking,  the actual  and
proposed formcoking will have  higher
NOx emissions from this source. Alterna-
tively ammonia could be recovered from
formcoking in the same manner as for
conventional coking.
   In the air mode, wastewater quantities
will  equal  conventional coking.  In the
operating mode  (steam/oxygen) with
high heating value gas recovered, the
formcoke process is expected to generate
up to 50 percent more wastewater for
treatment  than conventional coking
(when compared on the basis of recovering
benzene from both processes). Presum-
ably the wastewater from each can be
treated to give the same discharge
quality.  For  plants that might have to
provide full wastewater treatment instead
of pre-treatment followed by discharge to
a publicly owned treatment plant, the cost
could be a significant impact to overall
process economics.
  Sludge/solid  waste quantities for
which no uses have  been  identified are
also higher for formcoking than conven-
tional coking. Ultimate disposal  of the
sludge/solid  waste is  a  key issue. In
conventional  coking an analogous solid
by-product is coke breeze. In most cases
coke breeze is reintroduced to the  iron
and steelmaking process or sold. It is not
known if calcinate thickener sludge could
be handled similarly.
  A full assessment of formcoking would
necessarily  examine  trace element
emissions (heavy metals, etc.). Though no
direct measurements have been made on
a  formcoke  plant,  some data from
gasification  processes  with similar
fluidized-bed  operations were reviewed.
The  data are presented  not to  say a
problem with trace elements exists, but to
establish the importance of a more
thorough investigation.

Conclusions
  The study led to several conclusions:
  1)  Formcoke production will eliminate
many sources of hazardous air emissions
which are present in conventional coking
and are difficult to effectively control. The
formcoking process is more amenable to
air  pollution control  in  that there are
fewer potential emission sources and the
age deterioration of process equipment is
not as severe  as that which occurs in
conventional coke batteries.
  2) Formcoke production has the poten-
tial of significantly reducing worker
exposure to carcinogenic air emissions,
when compared to conventional coking.
  3) Formcoking is expected to produce
the same amount of (or up to 50 percent
more)  wastewater to be treated  and
sludge/solid  waste  for which  it is
desirable to find uses.
  4) With formcoking some trace element
and polycyclic organic matter concentra-
tion may occur, in the recycled wastewater
similar to continuous coal conversion
processes.  Data are  insufficient to
determine  the extent of buildup  and
identify satisfactory wastewater treat-
ment technology.
  5) Existing data are not sufficient for a
complete environmental  assessment of
formcoking.
  D. W. Coy, C. C. Allen, and B. H. Carpenter are with Research Triangle Institute,
    Research Triangle Park. NC 27709.
  Robert C. McCrillis is the EPA Project Officer (see below).
  The complete report, entitled "Preliminary Environmental Assessment on
    Formcoke Cokemaking Process," (Order No. PB 83-259 713; Cost: $10.00,
    subject to change) will be available only from:
          National Technical Information Service
          5285 Port Royal Road
          Springfield, VA 22161
          Telephone: 703-487-4650
  The EPA Project Officer can be contacted at:
          Industrial Environmental Research Laboratory
          U.S. Environmental Protection Agency
          Research Triangle Park, NC 27711
                                               ftUS GOVERNMENT PRINTING OFFICE 1984-759-015/7258

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