United States
Environmental Protection
Agency
Industrial Environmental Research *—fes
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S9-81-017 Sept. 1981
Project Summary
Proceedings: Symposium on
Iron and Steel Pollution
Abatement Technology for
1980
Franklin A. Ayer
This report summarizes the pro-
ceedings of the EPA Symposium on
Iron and Steel Pollution Abatement
Technology for 1980, held on No-
vember 18-20,1980, in Philadelphia.
The symposium brought together
representatives of Federal, state, and
' local government agencies, industrial
managers and engineers, iron and
steel associations, labor organizations,
health and physical scientists, and
equipment manufacturers and suppli-
ers with the objective of an exchange
of information on technology problems
related to air, water, and solid waste
pollution control in the iron and steel
industry.
The symposium was opened by
Robert V. Hendriks, General Chairman,
U.S. EPA, IERL-RTP, who welcomed
the participants and informed them
that the objective of the symposium
was to focus their attention on the
technological solutions to environ-
mental problems in the iron and steel
industry. Innovative technology and
ideas, improvements in design and
operating procedures, and results
from the latest assessment programs
would be covered. William Drayton,
Assistant Administrator for Planning
and Management of EPA, was the
keynote speaker. He gave a brief inside
look at the way regulations are devel-
oped and described some of the
Agency's efforts to develop regula-
tions that will ensure adequate envi-
ronmental protection at the lowest
possible cost. Michael Holowaty,
Inland Steel Company, described en-
vironmental aspects of the proposed
Inland Steel formcoke demonstration
plant; and Joel Hirschhorn, Office of
Technology Assessment, U.S. Con-
gress, presented the results of a study
describing the assessment of potential
future steelmaking technology and
important environmental considera-
tions.
Air pollution abatement emission
control was discussed by several
speakers under separate subtopics:
coke plant emissions - William Tucker
(Republic Steel Corp.), and Richard
Parker (Air Pollution Technology,
Inc.); fugitive emissions - Chatten
Cowherd (Midwest Research Institute),
S. L. Soo (University of Illinois at
Urbana-Champaign), and James
Steiner (Acurex Corp.); innovative air
pollution technology - Edward Brook-
man (TRC Environmental Consultants,
Inc.), Van Xirtgzhong (Safety Techno-
logy Research Institute, The People's
Republic of China), and Michael
Shackleton (Acurex Corp.); iron and
steelmaking emissions - Wayne
Westbook (Research Triangle Institute),
Thomas Nunno (GCA Corp.), Peter
Spawn (GCA Corp.), and Leon Hutten-
-------
Czapski (SIDBEC-DOSCO, Canada);
and inhalable particulates - Robert
McCrillis (EPA, IERL-RTP).
This Project Summary was devel-
oped by EPA's Industrial Environ-
mental Research Laboratory, Research
Triangle Park, NC, to announce papers
presented at the symposium that is
fully documented in a separate pro-
ceedings of the same title (see Project
Report ordering information at back).
Water pollution abatement was dis-
cussed by several speakers under sep-
arate subtopics: recycle/reuse of water -
Harold Hofstein (Hydrotechnic Corp.),
Wang Chingwen (General Research
Institute of Building and Construction,
The People's Republic of China), S.
Bhattacharyya (NT Research Institute);
coke plant wastewater treatment -
Bernard Bucchianeri (U.S. Steel Corp.),
Andrew Middleton (Koppers Company,
Inc.), Myrl Wear (Armco, Inc.); and coke
plant wastewater—new developments -
Richard Osantowski (Rexnord), John
Hall (National Steel Corp.), Henryk
Melcer (Environment Canada), Harold
Hofstein (Hydrotechnic Corp.), Ronald
Neufeld (University of Pittsburgh), and
George Lower (Michigan Technical
University).
Solid waste pollution abatement was
discussed by: Penelope Hansen (EPA),
Wayne Micheletti (Radian Corp.), Albert
Hoffman (Battelle), and L. A. Duval
(Colerapa Industries, Inc.).
The forum was highlighted by the
frank exchange of information between
government, industry, and research
participants on technology problems
related to air, water, and solid waste
pollution control in the iron and steel
industry. This interchange greatly im-
proved communications between par-
ticipants from industry and government
representatives. It is believed that closer
cooperation can be expected.
Summaries or abstracts of the speak-
ers' remarks follow:
Robert V. Hendriks, Chemical
Engineer, EPA, IERL-RTP
Hendriks welcomed the participants
and set the goals for the symposium. He
stressed the importance of focusing
attention on technological solutions to
environmental problems associated
with air, water, and solid waste in the
iron and steel industry. He stated that
significant progress within the past year
had been made in the control of pollution
problems. He further stated that future
progress will be made only if the spirit of
cooperation continues in the develop-
ment of technology required to meet the
industry's environmental needs in a
cost-effective manner.
William Drayton, Jr., Assistant
Administrator for Planning and
Management, EPA-Washington
Drayton said that after years of worry-
ing about regulatory detail by the Agency
and the worries of industry about the
bottom line, EPA is trying a new way of
doing business. Dollars and cents are
figuring prominently in regulatory pro-
posals. If a company can make a more
sensible counterproposal, one that
saves the company money and still gets
the environmental job done, EPA will
accept. The offset policy of earlier years
allowed industry to trade the right to
pollute while the more recent banking
concept provides additional cost savings
and incentives for innovation for not
polluting.
Drayton also said that the Agency
expects to expand the "bubble" concept.
This concept allows managers to look at
their facilities as a whole. In this way a
manager can go about controlling sev-
eral sources of pollution under the
"bubble" which he thinks makes the
most sense. In this way the "bubble"
can stretch beyond the plant boundaries
as long as air quality is protected.
D. C. Lang, Senior Advisor,
Research Dept, Inland Steel
Company
A brief history of the development of
formcoking processes for metallurgical
coke production is presented and blast
furnace evaluations of formcoke produced
with the FMC formcoking process are
reviewed. The flow sheet for the Inland
Steel formcoke demonstration plant is
presented and the emissions control
equipment and environmental advan-
tages of the FMC formcoke process are
discussed based on the results of re-
cently completed engineering studies.
Joel S. Hirschhorn, Project
Director, U.S. Congress, Office
of Technology Assessment,
Washington, DC
According to the OTA report Technol-
ogy and Steel Industry Competitiveness,
there are considerable opportunities for
major new steelmaking technologies to
be created and introduced in the domes-
tic steel industry during the coming
decades. During the decade of the
1980's there will be continued increases
in the use of scrap-based electric furnace
steelmaking by both nonintegrated and
integrated steelmakers. Moreover, there
will be substantial increases in the use of
continuous casting of steel. One of the
important impacts of these changes will
be the need to use direct-reduced iron as
a complement to ferrous scrap in electric
steelmaking furnaces. The shift to greater
scrap use and the gradually increasing
use of direct-reduced iron signifies less
dependence on ironmaking in blast
furnaces fueled primarily by coke. Thus,
pollution should be abated. Although
there may be very limited introduction of
coal-based direct reduction during the
1980's in the U.S., in the 1990's we may
see large-scale direct-reduction plants
based on coal gasification and more DR
plants using coal directly. Federal poli-
cies shape the development and use of
new technology. Those policies that aid
and reward the companies with the
poorest performance may be detrimental
to a competitive domestic steel industry,
such is the nature of President Carter's
proposal to grant extensions to the
compliance schedule for the Clean Air
Act to certain qualifying plants.
William B. Tucker, Jr., Assistant
to the Director, Environmental
Control, Republic Steel Corpora-
tion
This paper discusses coke oven
charging emissions from well controlled
coke oven batteries. They are found to
follow a statistical distribution that is
badly skewed toward long times, al-
though the mode and mean times are
short. Causes of occasional long emis-
sion times are explained. It is suggested
that charging emission standards of the
type that permit a limit of L seconds
visible emissions per N charges, such as
125 seconds per five charges, will
inevitably be violated and are inappro-
priate. The paper suggests that the
standard should be a limit on percent of
visible charge emissions exceeding 25
seconds. The limit should depend on
battery age and features. The paper
suggests compliance be determined
from an average derived from a month
or more of observations.
Richard D. Parker, Research
Manager, Air Pollution Technol-
ogy, Inc.
The Spray, Charging, and Trapping
-------
(SCAT) scrubber system is a unique
fugitive emission control system being
developed by Air Pollution Technology,
Inc. It has many potential applications in
the iron and steel industry including
major sources such as coke ovens and
blast furnaces. The SCAT scrubber uses
air curtains and push jets to contain,
divert, and convey the fugitive emissions
into a charged spray scrubber.
Experiments were performed on a
8,000 bench-scale spray scrubber to
verify the theory and demonstrate the
feasibility of collecting fugitive particles
with charged sprays. The effects of
charge levels, nozzle type, drop size, gas
velocity, and liquid-to-gas ratio were
determined experimentally. The experi-
mental data and theoretical predictions
are presented in this paper.
A prototype SCAT system was built
and tested on a crosswind and on a hot,
buoyant smoke plume. Theoretical
predictions and experimental data are
presented.
Chatten Cowherd, Jr., Associate
Environmental Engineer,
Midwest Research Institute
This paper presents empirically devel-
oped predictive emission factor equa-
tions for open dust sources in iron and
steel plants. The ranges of applicability
and the precisions of the equation are
discussed. Presently, the equations for
the two open dust sources of greatest
magnitude (unpaved and paved roads)
have good practices, with 68 percent of
the predicted values lying within factors
of 1.21 and 1.53 of the measured values
for unpaved and paved roads, respec-
tively.
Also presented are the results of tests
performed on control techniques to
mitigate fugitive dust from vehicles
traveling on unpaved roads. Limited
testing of chemical dust suppressants
for industrial unpaved roads indicates a
high initial control efficiency (exceeding
90 percent) which decreases more than
10 percentage points within about 24
hours after application. The emission
factor, equations are shown to be useful
in estimating control efficiencies in the
absence of adequate efficiency test
data.
S. L Soo, Professor of
Mechanical Engineering,
University of Illinois at
Urbana-Champaign
To reduce the wind blown dust from
storage piles of coal or other bulk
materials '«i«rt tunnel tests of scale
models - / made to determine the
effect of onfiguration and use of
wind barru to reduce wind penetra-
tion.
Preliminary results show that a wind
break or barrier simulating a snow fence
whose height is half the pile height with
a solidity of two-thirds may reduce the
penetration velocity of wind by half
when it is placed three pile-heights
away as an optimum. A similar barrier of
0.25 pile height located 2.5 pile-heights
away reduces the wind velocity by 23
percent. The effect of leeward barriers is
less obvious, however. Reduced wind
penetration into a pile also conserves
the moisture in the pile thus improving
the adhesion of dusts.
James Steiner, Manager,
Source Evaluation Programs,
Acurex Corporation
The Source Evaluation and Analysis
(SEA) Division of Acurex Corporation
undertook a series of tests for EPA
Region 5 at the hot metal desulf urization
plant of Kaiser Steel located in Fontana,
CA. The tests were performed to develop
emission factors (particulate mass,
particle size, SC<2) for uncontrolled and
controlled emissions from this process.
Edward T. Brookman, Project
Engineer, TRC-Environmental
Consultants, Inc.
A unique device for the control of
particulate emissions works on the
principle that most industrial pollutants
acquire an electrostatic charge as they
are dispersed into the air. If this charged
airborne material is exposed to an
oppositely charged water fog, the charges
act to enhance the contact between the
particulates and the fog droplets, result-
ing in rapid agglomeration and particle
fallout. A device that generates charged
fog has now been substantially devel-
oped and is being offered commercially
by The Ritten Corporation.
TRC-Environmental Consultants, Inc.
has been contracted by EPA/IERL-RTP
to test the Ritten Corporation's Fogger
IV on several large-scale fugitive dust
sources. This paper discusses the initial
test at a sand and gravel operation and
presets preliminary test results in terms
of percent reduction in TSP. The changes
in fogger effectiveness due to variations
in operational parameters are discussed.
The initial tests indicate overall fogger
efficiencies of approximately 70 percent.
Van Xingzhong, Vice Chief
Engineer of Safety Technology,
Safety Technology
Research Institute
In order to meet the needs for cleaning
large quantities of high temperature
fume from iron and steel plants, Safety
Technology Research Institute of Metal-
lurgical Industry Ministry of China has
developed a new type of gravel bed filter
in which the gravel bed fluidizes during
reverse cleaning. Being designed on the
principle of bulb forming and fluidiza-
tion, this kind of filter can clean dust
remaining in the filtrating bed byfluidized
backflushing without the rake stirring
mechanism. This helps the filter to be of
the towery type with multilayers.
In this paper, through theoretical
analysis and calculations, the authors
provide necessary data of fluidizing the
gravel bed. The application of this filter
in industry and the comparison of its
technology with that of ordinary gravel-
bed filters and other types of efficient
dry filters have shown that this filter is
simple in structure-and easy for main-
tenance. It takes up less space and
requires less capital cost as well. To the
present, this type of filter with a gas
volume of 120,000 mVhr has been run
in practice and its performance of
reverse cleaning is satisfactory.
Michael A. Shackleton, Program
Manager, Environmental
Engineering Section, Acurex
Corporation
A new filter media made from ceramic
fibers offers the potential for fine par-
ticulate control at gas temperatures up
to 1,000°C. These filter media represent
an emerging technology under develop-
ment for application to hot gas cleaning
in pressurized f luidized-bed combustion.
However, the ability to control particles
at extreme temperatures will offer
benefits to other industries as well. For
example, the 1,000°C filter will reduce
the need to dilute hot gas streams in the
iron and steel industry prior to particle
removal. The resulting clean hot gas ca n
then be used in a heat recovery system
to offset the cost of pollution control.
Progress to date in the development of
this new filtration device is reviewed in
this paper.
C. Wayne Westbrook, Senior
Environmental Engineer,
Research Triangle Institute
Fumes generated during hot metal
-------
charging of a BOF and a Q-BOP were
sampled and analyzed for total particu-
lates, paniculate mass in four size
ranges, and inorganic and organic
compounds. The data indicate that the
Q-BOP generates 3 times as much
paniculate and 15 times as much organic
matter per megagram of hot metal
charged as does the BOF. Polynuclear
aromatic hydrocarbons (PNA) were
found in the Q-BOP fume but not in the
BOF fume. No carcinogenic PNAs were
detected.
Thomas Nunno, Environmental
Engineer, GCA Corporation
This paper presents the findings of
week-long field evaluations of emission
controls of six BOF steelmaking shops.
The field evaluations included shops
with complete furnace enclosure, Gaw
damper plates, and tapside enclosures.
For each evaluation, process engineers
in the furnace control room and on the
operating floor carefully documented
process operations. Simultaneous with
in-shop process evaluation, outside
observers recorded visible emissions
from the shop roof monitors in accord-
ance with EPA Method 9. FM radio
contact between in-shop and outside
observers enabled documentation of
the sources of all roof monitor emis-
sions. Performance of each control
system is presented on the basis of
average roof monitor opacity for each
furnace operation; e.g., charge, oxygen
blow, tap. Also investigated were the
potential causes of roof monitor emis-
sions such as variations in steelmaking
procedures and/or emission control
operational variables.
Peter D. Spawn, Project
Manager, GCA Corporation
This paper provides an up-to-date
review of recent developments in blast
furnace casthouse control technology in
the U.S. Six casthouse control systems
were installed in the U.S. on a perma-
nent basis by the fall of 1980. Three
additional continuous-service casthouse
control systems are operating in Canada.
A number of prototype systems are
under development and demonstration
in the U.S. At this time the U.S. steel
industry has made commitments to
install controls on at least 41 casthouses.
The paper discusses current trends in
the U.S. and also describes operating
control systems in the U.S., Canada, and
West Germany.
Leon Hutten-Czapski, Technical
Assistant to the Engineering
Director, Sidbec-Dosco
The total efficiency of a dust control
system is a product of collecting and
filtering efficiencies. Most of existing
dust control systems for electric arc
furnaces have inefficient collecting and
very efficient filtering components. The
poor efficiency of collecting hoods is a
result of their distance from the source,
existing cross wind in the melt shop,
and lack of sufficient exhaust capacity
even at very high gas flow rates.
The only rational and economic solu-
tion is to capture the fumes at or close to
the source. The system installed at the
Sidbec-Dosco Contrecoeur melt shop is
employing retractable collecting hoods
located close to the ladle. It achieves
high collecting efficiency at low exhaust
rate of gas flow without interference
with the operation of the overhead
crane.
The paper provides technical and
economical analyses of several alterna-
tive solutions for dust collecting from
electric arc furnaces in steelmaking
plants.
Robert C. McCrillis, Mechanical
Engineer, EPA, IERL-RTP
EPA's Office of Research and Devel-
opment has entered into a major pro-
gram to develop inhalable particulate
matter (IPM) emission factors, where
IPM is defined as airborne particles of
15//m aerodynamic equivalent diameter.
The Metallurgical Processes Branch of
EPA's IERL-RTP is responsible for the
iron and steel industry segment of this
program. This paper is a summary of
efforts to date. Implementation has
proceeded along two major lines of
action. The first follows the classical
route: literature review, prioritization of
sources, identification of sources for
which existing data are adequate, selec-
tion of plants, testing, and finally report-
ing results. The other route consists of
meshing the IPM requirements with
those of other EPA sampling programs,
thus reducing overall cost to EPA and
minimizing inconvenience to the host
plants.
A review of existing particle size data
showed not only that relatively little
data exist, but also that most existing
data are of questionable quality. There-
fore, the field test program entails
sampling virtually all significant sources.
To date, tests have been completed of
basic oxygen furnace (BOF) charging
and tapping, hot metal desulfurization,
blast furnace cast house (building evac-
uation approach), uncontrolled paved
and unpaved roads, and BOF main stack
(limited combustion system after scrub-
ber). Discussions are now underway
with several plants to test other high
priority sources. It is anticipated that
funds will allow duplicate tests at another
plant of at least the highest priority
sources.
Harold Hofstein, Manager
Engineer, Hydrotechnic
Corporation
Much emphasis is being placed on
recycle, reuse, cascade, etc. systems for
reducing the amount of contaminants
discharged from industrial facilities.
These methods can and do reduce
volumes of water and masses of con-
taminants discharged; however, the
application of new principles to existing
facilities is usually looked upon with, at
best, extreme skepticism.
This attitude is understandable since,
in many cases, an existing system
cannot be completely or conveniently
revamped to include all the "niceties"
that can be designed into a greenfield
site. A completely closed mind, however,
cannot be tolerated in these days of
increasing prices and stricter environ-
mental controls. There is no room for
the attitude of "we've been doing it that
way for 30 years and no one can make
us do it differently." Attitudes like that
can only force management to spend
much more money than is really needed
to comply with the regulatory require-
ments for pollution control.
This paper presents various practices
regarding the reuse, recycle, and cas-
cade of wastewater in steel plants
which were either developed for green-
field installations (and later applied to
existing installations) or applied to
existing installations directly. It also
points out areas of difficulty which are
encountered when existing facilities are
upgraded. Design parameters must be
carefully determined so that facilities
are not grossly oversized or, more
tragically, undersized. The treatment
and reuse compatibility of one waste-
water with another must also be ascer-
tained so that incompatible "mixes" are
not attempted.
Segregation of flows within existing
mills, although initially costly in most
cases, can be the most economic alter-
native. This is especially true when
-------
large quantities of "clean cooling water"
combine with "dirty water." These
various methods are presented together
with descriptions of systems actually
installed and operating to show the
results that can be obtained with proper
study and design principles.
Wang Chingwen, Civil Engineer
and Head of Department of
Water Quality, General
Research Institute of Building
& Construction
The scale formed on the surface of
stainless steel during processing is
usually removed by pickling with nitric
acid and hydrofluoric acid. The pickling
liquid becomes waste acid when its
metal ions reach a certain concentra-
tion through repeated pickling. 'This
waste acid seriously affects the produc-
tion and pollutes the environment if it is
not properly treated.
Research work on the treatment of
nitric and hydrofluoric acids has been
carried out and some methods (e.g.,
chemical method, the method of ion
exchange, the method of solvent extrac-
tion, and the vacuum evaporation meth-
od) have been put into practice in the
European countries, the U.S., Japan,
etc.
Based on the data obtained from the
pilot test, a semi-continuous, one-step,
nitric and hydrofluoric acid regenerating
device by vacuum evaporation was
designed for a seamless steel pipe shop
in 1976 and put into operation in 1977.
Later, equipment was added for treating
residual liquid after acid recovery and
recovering ferrous sulfate and nickel
carbonate. The total capital construction
cost of this device can be paid off in 1
year. What is more, there will be no
secondary contamination.
Practice has proved that the method
has the advantages of simple equipment,
easy .operation, and high recovery ratio.
It is therefore an effective recovery
method.
S. Bhattacharyya, Manager,
Materials Technology, I IT
Research Institute
This study was directed to develop
information on ferrous sulfate hepta-
hydrate (copperas) produced by the steel
industry. Several major aspects of
copperas generation and disposal were
studied:
1. Pickling waste generation in inte-
grated steel industry and by secondary
processors, present practice, and future
directions.
2. Waste pickle liquor disposal tech-
nology and future development.
3. West European pickling technol-
ogy, centralized zonal waste pickling
liquor treatment concept, and cotreat-
ment of different industrial waste
streams.
4. Ferrous sulfate heptahydrate pro-
duction and end-use.
The study shows that out of 60 million
tonnes pickled, about one-third is pickled
with sulfuric acid, but except for very
small amounts going to the pigment
industry, most of the waste is disposed
of without any recovery of either free
acid or dissolved iron. Most of the
75,000 tonnes/year of iron sulfate
crystals produced is from secondary
industries; commercial plants produce a
similar quantity for pigment production,
starting from scrap and sulfuric acid.
While pigment production is more than
half of the present market for copperas,
potentially the largest future market for
copperas is likely to be sewage treat-
ment plants.
The study also shows that the rapid
changeover from H2S04 to HCI pickling
has ended and the relative price struc-
ture between the two acids may favor
H2SO4 in the future. However, all green-
field plants are likely to use HCI pickling
because the end product, if recycling is
practiced, is FezOs which can be utilized
in the plant.
Satisfactory copperas production
technology exists, and market expansion
into water-sewage treatments may
require a rapid expansion of copperas
production units—particularly, if re-
gional centralized facilities are encour-
aged and established on a cooperative
basis, each member paying for its
service proportional to the volume of
acid waste treated and getting commen-
surate credit for acid recovered.
Several recommendations have been
made for additional research and regu-
latory modifications to aid and enhance
greater use of copperas.
Bernard A. Bucchianeri,
Division Engineer of Chemical
Operations, U.S. Steel
Corporation
The U.S. Steel Corporation, in con-
junction with the Environmental Protec-
tion Agency, is conducting an extensive
experimental program to develop input
data relative to BATEA technology for
coke plant wastewaters. The program,
which involves testing on both bench
scale and the pilot scale, is concerned
with determining the optimum operating
criteria for coke plant biological treat-
ment systems. Once the optimum con-
ditions are identified, further investiga-
tions will evaluate the impact of the
addition of powdered activated carbon
to an optimized system.
As an initial step in identifying opti-
mum operating conditions, a separate
investigation was conducted to evaluate
the importance of precleaning of the
feedwater to the biological system. The
evaluation program centered on those
constituents falling into the two general
categories, suspended solids and "oil
and grease." Various removal techniques
were evaluated and the necessity for
achieving specific levels of influent
pretreatment was addressed. The valid-
ity of the resultant conclusions relative
to precleaning is supported by opera-
tional data from a 9,500 mVday (2.5 x
10s gpd) coke plant wastewater treating
facility.
Andrew C. Middleton, Manager,
Water Quality Engineering
Section, Koppers Company, Inc.
Once an activated sludge system has
been started up and brought to steady
operation, control methodology must be
applied to maintain it in such a state.
Additionally, during the life of the
system, the situation may change from
that of the original design, and the
control meth6dology must be capable of
maintaining control in such situations.
This paper presents a straightforward,
rapidly interpretable control methodol-
ogy based on solids retention time
(SRT); a methodology for determining
capacities of an existing system; and an
illustration of these for a coke plant
activated sludge system.
Myrl R. Wear, Senior Engineer,
Armco, Inc.
The wastewater treatment facility at
Armco's Hamilton Coke Plant in New
Miami, OH, has been equipped to simul-
taneously treat all wastewaters gener-
ated in the coke plant area. This includes
the waste ammonia liquors generated
by the battery flushing liquor system;
waste generated in the "Benzol Yard"
area by the crude light oil distillation
system; and sanitary sewage waste.
Prior to biological treatment, each
stream is pretreated to remove specific
pollutants. The waste ammonia liquor is
-------
processed in a "free" and "fixed"
ammonia still along with caustic soda
addition in the fixed still to remove the
majority of the ammonia, cyanide, and
other acid gases. The Benzol Yard waste
is processed in a gravity oil separator for
removal of free oil. After the above
steps, the waste streams are combined
and stored in a surge tank for hydraulic
and chemical equalization. The sanitary
wastes are collected and stored in an
aerated surge tank prior to combining
with the other waste streams. After
equalization, the wastes are mixed and
pumped to an extended aeration, activa-
ted sludge treatment system. This sys-
tem includes a minimum of 24 hours of
aeration with an integral common wall
clarifier. The clarifier incorporates a
sludge return system which uses the
surface flow produced by the submerged
turbine aerator to automatically and
continually recycle the settled sludge
from the clarifier to the aeration basin.
The clarifier is equipped with a sludge
scraper which acts in conjunction with
the mechanical aerator's flow pattern to
recycle the sludge. The system was
started in March 1979 but, because of
various start-up problems, did not attain
complete operational status until mid-
October 1979.
The paper provides information on
various construction and start-up prob-
lems in addition to construction capital
and operating costs. Performance data
for the first year of operation are pre-
sented and discussed.
Richard A. Osantowski, Research
Engineer, Rexnord Corporation
Pilot studies were performed con-
currently at two coke plants to investigate
the effectiveness of physical/chemical
and biological treatment in meeting
steel industry BAT guidelines for the by-
product cokemaking subcategory.
John D. Hall, Environmental
Research Chemist, National
Steel Corporation
A laboratory scale study of single-
stage, phenol oxidation-nitrification
activated-sludge treatment of coke
plant wastewater was conducted. The
objectives of the study were to determine:
• The operating conditions at which
a treated effluent would contain an
ammonia concentration of 10mg/l
or less.
• The effects of sudden changes in
loadings of certain wastewater
constituents on the biological
process.
• The effects of the process on priority
organic pollutants.
• Means of enhancing the biological
process.
In this study, eight test reactors were
used; the feed to these reactors was
undiluted ammonia still waste which
was amended to a constant composition
of ammonia, phenol, and thiocyanate.
The results of the study show that the
single-stage phenol oxidation-nitrifica-
tion process can produce high degrees
of treatment for ammonia, free cyanide,
phenol, thiocyanate, and sulfide but it
was ineffective in treating complex
cyanide. This process is also effective in
controlling priority organic pollutants
found in coke plant wastewater. Sudden
changes in the reactor loadings of
conventional pollutant constituents.
resulted in neither toxic nor prolonged
inhibitory effects. However, the process
was sensitive in responding to abrupt
changes in feed composition and reactor
composition. These responses to
changes should be tested on a full scale
operation so that the true impact of
normal coke plant operations can be
assessed. The preliminary evaluation of
activated carbon addition, carbonate
addition, and commercial mutant bac-
teria addition as means of enhancing
(increasing the rate of nitrification) was
inconclusive.
Henryk Melcer, Process
Development Engineer,
Environment Canada
Bench scale treatability studies were
conducted to evaluate the performance
of the single sludge pre-denitrification
nitrification process configuration for
nitrogen and contaminant control of
coke plant effluents.
Complete nitrogen control was
achieved provided wastewater dilution
was practiced or low levels of powdered
activated carbon (PAC) were added to
the bioreactors. The minimum aerobic
SRT required to achieve complete nitri-
fication at 20-24°C was 22 days. Opera-
tion at high system, SRT (60 days) did
not facilitate nitrification of undiluted
wastewater. However at anoxic and
aerobic HRTs of 0.5-1 and 1-3 days,
respectively, complete nitrogen control
and high levels of contaminant removal
were effected in undiluted wastewater
by maintaining a PAC level of 500 mg-L"1
in the reactors. The equivalent PAC
feed concentrations ranged from 20 to
50 mg-L"1. The addition of PAC overcame
Nitrobacter inhibition, which was evident
in the treatment of both diluted and
undiluted wastewater.
The organic carbon in the wastewater
was used as the energy source for
denitrification and no supplemental
organic carbon was required to achieve
complete denitrification provided the
feed FOC/TKN ratio >3.5.
The fate of trace organics was moni-
tored using GC/MS methodology. En-
hanced trace organic removal was ef-
fected through PAC addition.
Parallel units operated with and
without calcium indicated that up to
3000 mg-L~1 of dissolved calcium in the
wastewater was not detrimental to
biological activity. Analysis confirmed
that calcium phosphate tetrabasic was
precipitated discretely in the reactors.
Phosphoric acid requirements increased
tenfold when calcium was present.
Harold Hofstein, Manager
Engineer, Hydrotechnic
Corporation
Some unusual treatment techniques
for blast furnace gas cleaning waste-
waters were found during a study of
foreign steel mill wastewater treatment
processes for gas cleaning wastewater
and for by-product coke plant waste-
water. The study was made to see if
more advanced processes were used in
foreign mills than in domestic ones.
Discussions were held with plant and
corporate personnel at 26 plants in 14
countries and with regulatory agencies
in 10 of the 14 countries, to determine
the regulations imposed upon the plants,
the incentives provided to reduce pollu-
tion loads to receiving waters, and to
investigate treatment technology.
Treatment of by-product coke plant
and blast furnace gas cleaning waste-
waters is generally not more advanced
in foreign plants than in the U.S. How-
ever, blast furnace gas cleaning water
in foreign plants is generally recycled to
a greater degree, although some plants
were observed with recycle rates of less
than 50 percent.
Aeration of gas cleaning waste-
water prior to clarification improved
settling and resulted in a greater rate of
recirculation. Filtering the wastewater
through slag or flue dust removed
cyanide, although the removal mecha-
nism is not known.
Recommendations for research proj-
ects are made as there appears to be
promising areas for improvement of
wastewater treatment techniques.
-------
Ronald D. Neufeld, Associate
Professor of Civil Engineering,
University of Pittsburgh
Laboratory experiments were con-
ducted on the rate of ammonia biooxida-
tion by an autotrophic culture of strict
nitrifiers. The quantitative influence of
pH, unionized (free) ammonia, phenol,
and elevated temperatures on Michaelis-
Menten type nitrification biokinetics
was evaluated.
Total ammonia and pH act via a
"substrate inhibition" mechanism to
nitrification. The maximum specific rate
of nitrification decreases proportionally
to the square root of ambient phenol
concentrations. Temperatures in excess
of 30°C decrease the maximum specific
rate of nitrification, decrease nitrifier
yield coefficients, and increase the
Michaelis-Menten constant leading to
an overall decrease in rate kinetics and
potential process instabilities at such
elevated temperatures. Conclusions.
based on engineering calculations are
presented to illustrate design and oper-
ational considerations for the biological
removal of wastewater ammonia.
George W. Lower, Professor
of Metallurgical Engineering,
Michigan Technological
University
Distribution curves indicate that long-
chain quaternary amines will complex
cyanide, ferrocyanide, andferricyanide.
The neutral organometallic complexes
formed are hydrophobic because of the
long-chain alkyl groups of the amine
and therefore should be capable of
attachment to an air bubble and con-
centrated in the froth product. This
concept was tested on synthetic ferricy-
anide solutions and (to a limited extent)
on ferrocyanide solutions in a small
continuous flotation column. Ferricyanide
removal was found to be a function of
retention time, initial ferricyanide con-
centration, mole ratio of amine to ferri-
cyanide, and chloride interference. The
air flow rate and solution pH in the
range of 4 to 10 had relatively minor
effects. Under optimum conditions
ferricyanide removals of approximately
80 percent were achieved in a single-
stage flotation.
Penelope Hansen, Program
Manager of the Minerals and
Energy Program, EPA-
Washington
The Resource Conservation and Re-
covery Act (P.L 94-580) requires EPA to
develop criteria for industrial solid
waste management practices. The iron
and steel industry generates a wide
variety of solid wastes. A number of the
wastes (for example, dust/sludge from
electric furnace production of steel,
spent pickle liquor) have been listed as
hazardous and thus are subject to certain
Standards applicable to hazardous
waste generators and transporters and
owners/ operators of hazardous waste
treatment, storage, and disposal facilities.
These standards address such topics as
waste manifests, general facility stan-
dards, groundwater monitoring, closure/
post-closure, landfills, and underground
injection of wastes.
Those wastes which are determined
to be nonhazardous will be called upon
by the States to meet EPA's Criteria for
Land Disposal of Solid Waste. Siting in
floodplains, discharge to surface water,
contamination of groundwater, and
numerous safety provisions are a few of
the main subjects addressed by these
criteria.
In effect, all steel industry solid waste
falls under the purview of either the
hazardous or the nonhazardous solid
waste disposal regulations.
Solid wa'ste management has become
an area of increasing concern as a result
of increasing disposal costs, scarcity of
adequate disposal areas, and the need
for increased protection of public health
and the environment. EPA is committed
to a solid waste management program
that will not only alleviate the environ-
mental concerns associated with dis-
posal but at the same time maximize the
reuse/recycle of waste materials such
that energy and resource conservation
will be encouraged and achieved.
Wayne C. Micheletti, Senior
Engineer, Radian
Corporation
Each year, sulfuric acid pickling of
steel produces approximately 600 million
gallons of spent sulfuric pickle liquor
(SSPL). Currently, contract hauling is
the most prevalent SSPL disposal
method. Only a small portion of the
SSPL is processed for sulfuric acid
recovery. Resource recovery and envi-
ronmental protection objectives favor
recovery instead of disposal. Commer-
cial recovery processes involve separa-
tion of iron salts resulting in a relatively
pure ferrous sulfate by-product. This
paper summarizes a recent study of
alternate SSPL recovery technologies,
the identification of valid end uses for
the ferrous sulfate by-product, and
process economics.
Albert 0. Hoffman, Associate
Section Manager, Battelle
Columbus Laboratories
The objective of this study was to
investigate existing and emerging
processes for the reclamation of the
three largest quantities of iron-bearing
solid wastes being landf illed by the steel
industry—oily mill scale, steel making
dust, and blast furnace dust and sludge.
The processes considered are designed
to remove contaminants to the degree
that resource recovery (recycle) can be
practiced. This paper summarizes the
results of this study in terms of process
identification and description, appraisal
of the environmental aspects of recla-
mation (including appraisal of the po-
tential for new environmental problems),
and the economics and energy require-
ments of the various processes.
L. A. Duval, President, Colerapa
Industries, Inc.
"Hazardous Waste" is a classification
which has recently been expanded to
include significantly more steel mill
waste streams. Oil-laden rolling mill
scale and sludge is one type of waste
which is included in this now broader
category. Management of these oily
wastes has always been difficult for the
steel industry, but the EPA's new regu-
lations make the problem even more
complex.
Disposal costs have been soaring and
will continue to do so as currently used
sites are exhausted and more remote
locations must be secured. Future water
quality standards will probably result in
• a further increase in waste disposal
costs.
The high iron content of oily wastes
has long been recognized as valuable,
but increasingly stringent air quality
regulations have all but eliminated their
reuse in sintering facilities. Agglomera-
tion techniques have also been generally
unsuccessful because of the oil content
of these sludges. The many obstacles to
their reuse, combined with the costs
and complexities of disposal, create a
complex problem for the steelmaker.
Colerapa Industries has developed a
technique for dealing with waste sludges
which affords the steelmaker a most
attractive alternative to an otherwise
bleak situation. The Colerapa system
starts with oily waste handling at the
-------
point of initial collection, using proprie-
tary equipment to hydraulically excavate
and transport these sludges. A process
system is then utilized which separates
• the iron from the hydrocarbon contam-
ination.
The complete process provides the
steelmaker with five specific benefits:
1. Greatly improved solids collection
efficiency.
2. Elimination of the problems nor-
mally associated with sludge ex-
cavation and transportation.
3. Significant (in some instances,
total) waste volume reduction.
4. Production of a high quality iron
source, suitable for use in any
agglomeration operation.
5. Recovery of oil from reclaimed mill
scale for reuse as fuel.
Franklin A. Ayeris with Research Triangle Institute, Research Triangle Park, NC
27709.
Robert V. Hendriks is the EPA Project Officer (see below).
The complete report, entitled "Proceedings: Symposium on Iron and Steel Pollu-
tion Abatement Technology for 1980," (Order No. PB 81-244 808; Cost:
$42.50, 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
•ft US GOVERNMENT PRINTING OFFICE. 1981 — 757-012/7346
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Postage and
Fees Paid
Environmental
Protection
Agency
EPA 335
Official Business
Penalty for Private Use $300
PS Ouyj3?v
------- |