-f/EPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S2-80-107 May 1981
Project Summary
Physical/Chemical
Treatment of Blast Furnace
Wastewaters Using Mobile
Pilot Units
R. Osantowski, A Gemopolos, J Kane, and G. Rollinger
This project was initiated to provide
an evaluation of the effectiveness of
existing treatment technology for
upgrading steel mill wastewaters to
Best Available Technology (BAT) Eco-
nomically Achievable limits for Blast
Furnace Category scrubber waste-
waters. The wastewater tested was a
blast furnace effluent from an operat-
ing steel mill treatment system that
met 1977 Effluent Guidelines for Best
Practical Control Technology (BPT)
Currently Available. This wastewater
contained residual concentrations of
suspended solids, BOD, oils and
greases, phenols, cyanides, fluorides,
ammonia compounds, sulfides, and
dissolved solids. The in-depth pilot
plant study was performed using
mobile facilities designed especially
for treating steel plant wastes.
Treatment processes evaluated
during the study included: alkaline
chlorination, chemical treatment, dual
media filtration, magnetic filtration,
reverse osmosis, ozonation and acti-
vated carbon.
Based on the performance results of
the pilot program, it was concluded
that the physical/chemical technology
investigated (alkaline chlorination,
ozonation, and reverse osmosis) was
effective in reducing influent blast
furnace scrubber wastewater contam-
inants to below BAT levels. Evaluation
and comparison of the treatment train
capital and operating costs determine
that alkaline chlorination was the
least-cost alternative. The study also
concluded that significantly less space
was required for the treatment train
utilizing ozonation than for treatment
trains involving alkaline chlorination
or reverse osmosis.
This Project Summary was devel-
oped by EPA's Industrial Environ-
mental 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
In 1972, the Federal Water Pollution
Control Act (PL92-500) was enacted by
the U.S. Congress. The Act directed the
U.S. Environmental Protection Agency
(U.S. EPA) to develop effluent limitation
guidelines for all major industrial groups,
among them the steel industry. EPA
was also mandated to recommend
appropriate levels of treatment and
estimate costs to meet the proposed
limitations. As part of its overall mission,
the EPA's Industrial Environmental
Research Laboratory of Research Tri-
angle Park, NC, funded this study to
determine the feasibility of treating
steel plant wastewater to Best Available
Technology (BAT) Economically Achiev-
able levels. This particular project was
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concerned with the treatment of blast
furnace scrubber blowdown wastewater.
The project objective was achieved
through the performance of a program
consisting of the three phases outlined
below:
PHASE I - Bench Scale Investiga-
tions of a Blast Furnace
Scrubber Blowdown
Wastewater.
PHASE II - Design and Fabrication
of the Mobile Treatment
Facilities to House the
Pilot Scale Equipment.
PHASE III - Operation and Evaluation
of the Advanced Waste
Treatment Pilot Plant Sys-
tems at a Blast Furnace
Site.
The purpose of the first phase (bench-
scale work) was to provide information
concerning the treatment methods to be
studied for the Phase II design and the
Phase III pilot plant investigation (opera-
tion and evaluation). Of particular
interest were such items as the pre-
treatment requirements, magnitude of
operating variables, expected magnitude
of treatment efficiency and effluent
quality, selection of equipment and
media, and pilot plant system design.
The second phase objective (System
Design and Fabrication) was to provide a
mobile pilot testing system for evaluating
several advanced waste treatment tech-
nologies. The portable treatment system
developed included the technology
needed to remove the residual contami-
nants from the blast furnace BPT waste-
water to the extent that this wastewater
was upgraded to meet BAT requirements
as proposed in 1974. Schematic repre-
sentations of the mobile testing systems
are shown in Figures 1 and 2. Trailer No.
1 housed the alkaline chlorination,
chemical treatment, magnetic filtration,
and dual media filtration systems. The
ozonator, activated carbon, and reverse
osmosis technologies were located in
Trailer No. 2. The mobile system con-
tained a high degree of automation
which greatly assisted the operators
during the study. All of the treatment
technologies were designed to treat a
nominal flow of 18.9 l/min (5 gpm).
The advanced waste treatment meth-
ods, both singularly and in combination,
investigated on a pilot basis in Phase III,
included the following:
1. FIL + O + CT
2 ACL + CT + AC
3 CT + FIL + RO + O (on ROB)
4. CT + FIL + RO + ACL (on ROB)
Chemical Tanks
Magnetic Dual Media Air
Filter Filter Compressor
Flocculator
Trailer
45'L x8'W x 13'-6"H
Four Chamber
Rapid Mix Tank
Clarifier
Figure 1. Steel plant mobile treatment system-trailer No. 1.
Trailer
45'L x8'W x 13'-6"H
Sample Carbon
Refrigerator Columns
Ozone
Generator
Clarifier
Reverse Osmosis
System
Ozone Contact
Tanks
Figure 2. Steel plant mobile treatment system-trailer No. 2.
Key
AC: activated carbon
ACL: alkaline chlorination
CT: chemical treatment
FIL: filtration-dual media or magnetic
0: ozonation
RO: reverse osmosis
ROB: reverse osmosis brine
A schematic illustration of the process
trains investigated for treatment of the
blast furnace wastewater is shown in
Figure 3.
For each treatment train investigated,
samples and operational data were ob-
tained for later use in assessing, evalu-
ating, appraising, and comparing the
adequacy of the individual advanced
waste treatment methods.
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(11 Filtration, Ozonation Clarification
NaOH Air
Poly
Raw
DMF
MF
~*.
-*.
|
03
Acid
C
Y
^
— »
Product
Sludge
(2) pH Adjustment, Alkaline Chlorination, Chemical Treatment, Clarification,
Filtration, Carbon Adsorption
Metal
NaOH Acid Salt
\NaOCI\NaOCI\ Poly
Alkaline Chlorination
(3) Chemical Treatment, Clarification, Filtration, Reverse Osmosis, Alkaline
Chlormation (on brine). Carbon Adsorption
Metal
Salt Poly , , Acid
NaOH Acid
NaOCI I Poly
Alkaline Ch/orination
(4J Chemical Treatment, Clarification, Filtration, Reverse Osmosis,
Ozonation (on brine). Clarification
Metal
Salt
Poly
Acid
Air Poly
NaOH I Acid j
i_ToLi_i
Key
AC: Carbon Adsorption
C: Clarification
DMF. Dual Media Filtration
MF. Magnetic Filtration
O3. Ozonation
RO: Reverse Osmosis
Figure 3. Process trains investigated for treatment of the blastfurnace wastewater.
Conclusions
This report was concerned with the
investigation and evaluation of the
effectiveness of selected physical/
chemical treatment technology on Blast
Furnace category scrubber wastewaters.
Effectiveness was measured using the
criteria: performance, costs and space
requirements. Physical/chemical treat-
ment technology investigated included:
chlorination, ozonation, reverse osmosis,
chemical treatment, clarification, acti-
vated carbon, and filtration. General
conclusions from this pilot scale investi-
gation are listed below:
1 The results of the pilot program
indicated that alkaline chlorination,
ozonation, and reverse osmosis
were effective in reducing influent
contaminants to below BAT levels
in the treatment of blast furnace
scrubber blowdown.
a. Pretreatment requirements.
1. For alkaline chlorination
none
2. For reverse osmosis: chem-
ical clarification and filtra-
tion
3. For ozonation. filtration
b. Post-treatment requirements
1 For alkaline chlorination
chemical clarification and
possibly activated carbon.
The activated carbon might
be required where free
chlorine discharge limita-
tions are in effect. Other
methods of chlorine re-
moval were not investi-
gated.
2. For reverse osmosis: brine
treatment by alkaline chlo-
rination or ozonation.
(a) Following alkaline chlo-
rination of the reverse
osmosis brine, the
wastewater would re-
quire clarification with
polymer and dechlon-
nation by activated
carbon (where dechlo-
rination is required
prior to discharge).
(b) After reverse osmosis
brine treatment by
ozonation, clarification
with polymer is re-
quired.
2. Alkaline chlorination was the
least-cost alternative treatment
train investigated Expected capital
investment for a 5,678 mVdav
(1.5 mgd) train is $1,171,300. Tr
i US GOVERNMENT PRINTING OFFICE 1981 -757-C
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corresponding operating costs
including amortization of capital
are estimated at $2 68/3,785
liters ($2.68/1,000 gal.).
3. Ozonation has the lowest system
area requirement of 676m2(7,100
ft2). This compared to 938 m2
(10,100 ft2) for the alkaline chlo-
rination treatment train.
4. The three treatment trains investi-
gated (alkaline chlormation, ozon-
ation, and reverse osmosis) were
all able to reduce the priority
pollutant to metals to 10/ug/l
except for zinc and selenium. BIS-
(2 ethylhexl) phthalate (BEP) was
the only organic reported above
the 10/yg/l verification limit.
Bibliography
1. Perry, J. H., Chemical Engineers'
Handbook, 4th Edition, McGraw-Hill
Book Company, New York, 1963.
2. Singer, P. C. and Zilli, W. B., "Ozon-
ation of Ammonia In Wastewater,"
Water Research, Volume 9, pp. 127-
134, 1975.
3. Eisenhauer, H. R., "Increased Rate
and Efficiency of Phenolic Waste
Ozonation," Journal WPCF, Volume
43, No. 2, February, 1971.
4. Selm, R. P., "Ozone Oxidation of
Aqueous Cyanide Waste Solutions
In Stirred Batch Reactors and Packed
Towers," Advances In Chemistry,
Series No. 21, American Chemical
Society.
5. Permasep Technical Information
Manual, Permasep Permeators, Du-
Pont, July 15, 1974.
R. Osantowski, A. Geinopolos, J. Kane, and G. Rolliriger are with Rexnord, Inc.,
Milwaukee, W I 53201.
Robert V. Hendriks is the EPA Project Officer (see below).
The complete report, entitled "Physical/Chemical Treatment of Blast Furnace
Wastewaters Using Mobile Pilot Units,"(Order No. PBS 1-159 386; Cost:$24.50,
subject to changej 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
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
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