EPA-660/2-73-032
January 1974
Environmental Protection Technology Series
Sulfuric Acid and Ferrous Sulfate
Recovery From Waste Pickle Liquor
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Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards.
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price $1.20
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EPA-660/2-73-032
January 1974
SULFURIC ACID AND FERROUS -SULFATE
RECOVERY FROM WASTE PICKLE LIQUOR
By
Joseph K. Seyler
William E. Thornton
Michael K. Householder, PhD
Project 12010 FNM
Program Element No. 1B2036
Project Officer
James H. Phillips
Office of Research and Development
U. S. Environmental Protection Agency
One North Wacker Drive
Chicago, Illinois 60606
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U. S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D. C. 20460
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ABSTRACT
A bath bar pickler and a bath rod pickler are used for cleaning ^0,000
tons per year of cold-rolled steel using sulfuric acid at the
Fitzsimons Steel Company's Youngstown, Ohio plant. Prior to this
project the plant produced up to 55,000 gal/month of spent liquor con-
taining up to 5 percent of free sulfuric acid and up to 0.85 Ibs/gallon
of iron and kBQO gal/day of rinse water containing 2,^00 ppm of free
acid and 2^,000 ppm of FeSOjj at a pH of 5.
A facilit-v for the treatment of the spent pickle liquor including rinse
water was installed based on the vacuum crystalization process of Keram
Chemi-Lurgi. This process recovers ferrous sulfate heptahydrate as a
nearly dry solid by-product and recovers the unreacted acid for recycle
to the pickling tank thus eliminating the discharge of spent pickle
liquor and rinse water. This report describes the investigation of
process variables and the demonstration of the process at full scale.
The full scale facility achieved acid recoveries equivalent to 21.2
tons/day of 12% sulfuric acid for recycle and an average of 115 Ibs/hour
of 99.56% FeS04'7H20 by-product. Capital costs were $191,710 or
$19,739/year based on a fifteen year life at 6% Interest. Net operating
costs were $42,320/year including a $21 ,i»00/year benefit from acid
recovery. (No credit of $2,300/year of ferrous sulfate heptahydrate was
included due to the nationwide excess production over market absorbing
ability). The total costs were $62,059/year, $1.75/ton of steel
pickled, 0.61** $/$ total sales, or $12.93/cubic meter of wastes treated.
This report was submitted in fulfillment of Project 12010 FNM under the
partial sponsorship of the Enviromental Protection Agency. Work was
completed as of December 1972.
Key Words: Sulfuric acid, Spent pickle liquor, Ferrous Sulfate
heptahydrate, Acid recovery, Crystallization, Centrifugation.
ii
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CONTENTS
Page
Abstract ii
List of Figures v
List of Tables vi
Acknowledgements viii
Sections
1 Conclusions 1
II Recommendations 3
III Introduction 4
A. The Magnitude of the Problem; Number and
Geographical Distribution of Pickling Plants 4
B. Estimate of the Pollution Load Due to
Sulfuric Acid Pickling Operation 4
C. Processes Available for Treating Sulfuric
Acid Pickle Liquor 6
IV The Problem at the Fitzsimons Steel Plant 8
A. Steps Taken by the Fitzsimons Steel Company 8
B. Benefits from the Acid Regeneration 10
V Basic Design Criteria 19
VI Rinse Water Studies 27
VII Market Survey of Ferrous Sulfate 37
VIII Exploratory Program to Evaluate the Conversion
of Ferrous" Sulfate to Other Products 40
A. Chemical Analysis of the Recovered Ferrous
Sulfate Heptahydrate 40
B. Conversion to Other Products 42
i
1. Fused Magnetite and Sulfuric Acid 42
2. Ferrous Sulfate Roasting - Contact
Sulfuric Acid Plant 42
iii
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Sections Page
IX Economic Estimates 45
A. Capital Costs 45
B. Normal Operation 45
C. Special Operation 45
D. Cost Summary 49
E. Resource Utilization 49
X References 54
XI Appendix 55
A. Operating Records 55
B. Market Survey on Ferrous Sulfate 55
1. Introduction 55
2. Objectives and Procedural Steps 55
3. National Markets 59
a) Producers 60
b) Market Segmentation 61
4. Local Markets 62
a) Market Segments 63
b) Testing Programs 68
5. Other Sales Factors 70
iv
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FIGURES
NO. PAGE
1 Distribution of Steel Finishing Plants 5
2 Outline of Fitzsimons Batch Pickling Operation Prior to
Acid Recycle and Iron Recovery Process 9
3a Equipment Diagram of Acid Recycle Plant 11
3b (continued) 12
4 Overall View of Acid Recycle and Iron Recovery Building 13
5 Instrument Panel of Acid Recycle and Iron Recovery System 14
6 Recycled Acid Holding Tank 15
7 Pre-cooler and Cooling Crystallization 16
8 Steam Ejectors with Condensing Units 17
9 Centrifugal Thickener and Centrifuge 18
10 Ferrous Sulfate in Aqueous Sulfuric Acid Solutions 26
11 Total Iron vs. Time for Bar Mill Rinse Water 30
12 Ferrous Iron vs. Time for Bar Mill Rinse Water 31
13 Ferric Iron vs. Time for Bar Mill Rinse Water 32
14 Sulfate vs. Time for Bar Mill Rinse Water 33
15 Acid Recycle System with Rinse Water to Waste 35
16 Acid Recycle System Treating Rinse Water 36
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TABLES
NO. PAGE
1 Ferrous Sulfate Monohydrate Dissolution in Sulfuric
Acid Solutions (0°C-60°C) 20
2 Ferrous Sulfate Monohydrate Dissolution in Sulfuric
Acid Solutions (80°C-100°C) 21
3 Ferrous Sulfate Heptahydrate Dissolution in Sulfuric
Acid Solutions 22
4 Transition Points of Ferrous Sulfate in Sulfuric
Acid Solutions 23
5 Ferrous Sulfate Monohydrate Dissolution in Sulfuric
Acid Solutions (Interpolated-) 24
6 Ferrous Sulfate Heptahydrate Dissolution in Sulfuric
Acid Solutions (Interpolated) 25
7 Summary of Rinse Water Use 29
8 Rinse Water Pollution Prior to Treatment 34
9 Analysis of A Salt Sample Identified as
"Ferrous Sulfate Heptahydrate" 43
10 Comparison of Recovered Salt with Theoretical Ferrous
Sulfate Heptahydrate 44
11 Capital Expenses for the Acid Recycle and Iron Recovery
Process 46
12 Operating Benefits and Costs for Normal Operation
(Salt Asset) 47
13 Operating Benefits and Costs for Normal Operation
(Salt Liability) 48
14 Operating Benefits and Costs for Special Operation 50
15 Cost Summary 51
16 Resources Utilization for Normal Operation 52
vi
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Tables Con't.
NO. PAGE
17 Resources Utilization for Special Operation 53
18 Operating Consumptions of the Acid Recycle and
Iron Recovery Plant 56
19 Production, Shipment, and Dollar Value of Ferrous
Sulfate "Commercially Produced" 59
20 Commercial Producers of Ferrous Sulfate 60
21 Distribution of Ferrous Sulfate Consumers 61
22 Current Usage and Relative Market Potential of Ferrous
Sulfate in the Youngstown, Ohio Trading Area 64
vii
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ACKNOWLEDGEMENTS
The authors would like to acknowledge the following people for their
help: Mr. Fred Proverbs of Keram Chemie, (Canada) and Mr. Ernie
Rudi of Lurgi, (Germany) for the installation and startup of the
Acid Recycle and Iron Recovery process; Dr. John D. VanNorman,
Associate Professor of Chemistry at Youngstown State University for his
chemical analysis; Mr. Richard Andres of Marketing Service Associates,
Inc. for the Market Survey of Ferrous Sulfate Heptahydrate; and finally
Mr. Robert L. Feder, Office of Solid Waste Management Programs,
Environmental Protection Agency, Cincinnati, Ohio and Mr. James H.
Phillips, Office of Research and Development, Region V, Environmental
Protection Agency, Chicago, Illinois, Project Officers for the Environ-
mental Protection Agency.
viii
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SECTION I
CONCLUSIONS
This project clearly demonstrates the ability to recycle waste sul-
furic acid pickle liquor by recovering sulfuric acid and ferrous
sulfate heptahydrate.
A_. Operations
1. The raw waste loads were reduced from ^0 pounds of free acid
and 400 pounds of FeSO^ per ton of steel pickled, discharged
as spent pickle liquor, to no discharge of spent pickle
1iquor.
2. The Treatment facility recovered the equivalent of 21.2
tons/day of 12% f^SOjj, formerly .discharged as spent pickle
liquor, for recycle to the pickling tanks.
3. The facility recovers 1 ton/day of ferrous sulfate hepta-
hydrate as a nearly solid by-product which was formerly
discharged as FeSO^ in the spent pickle liquor.
k. With pre-evaporators installed on the rinse water system and
more efficient rinsing the 1.1 pounds of free acid and 11
pounds of FeSOif per ton of steel pickled will be recovered
with no di scharge.
B. Economics
1. Capital costs for a design capacity of 316 gal/hour (1.2
cubic meters/hour) of waste pickle is $19,100/year based on
a 15 year amortization at 6% interest.
2. Operating costs were $i»2,320/year, taking credit for the value
of the acid recovered.
3. Total plant costs were $61,^20/year.
**. Total costs are $1.73/ton of steel produced.
5. Total costs are 0.605$/$ total sales.
6. Total costs are $12.79/cubic meter waste treated
C. Rinse Water Studies
1. Rinse water studies indicate that if the present rinse water
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volumes of 298 gallons/hour were reduced to k gallons/hour
with the use of pre-evaporators they could be treated with
the Acid Recycle and Iron Recovery System.
2. Methods ore dvdliable for heating pickle tanks without dilu-
tion thereby reducing the volume contribution to the system.
3. Rinse water volumes c«n be reduced by more efficient rinsing
techniques.
D. Market Survey of Ferrous Sulfdte Heptdhydrdte
1. The national market for ferrous sulfate is in a glutted
condition. Production capacity far exceeds demand.
2. The Fitzsimons product has been shown to be certified reagent
grade by an analysis of the product. That is to say, the
material apparently can compete for markets with commercially
produced ferrous sulfate and is far superior to the spent
pickle liquor type of ferrous sulfate generated by many steel
mills.
3. The local market (75 mile radius) for ferrous sulfate is
currently negligible. Very little is now being used in any of
the various potential end-use markets.
k. Even though the market (current use) is negligible, the pros-
pects for selling the Fitzsimons ferrous sulfate within the
local trading area appears to be quite good. This is because
the product is purified more than the normal type of ferrous
sulfate spent pickle liquor and can be priced well within
current pricing schedules.
5 Nine firms and/or cities are currently testing the product
with the Mahoning Valley Sanitary District, the most genuinely
interested based on their tests at the time of this writing.
E. Exploratory Program for Conversion of Ferrous Sulfate Hyptahydrate
1. The ferrous sulfate heptahydrate recovered is of very high
quality.
2. There are methods available for converting this salt to mag-
netite and sulfuric acid.
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SECTION II
RECOMMENDATIONS
Rinse Water
1. Install pickle tank heaters that do not dilute the pickle
1 iquor.
2. Reduce dragout volumes by allowing the pickle liquor to
drain off steel while suspended above pickle tank.
3. Install a more efficient rinsing system by the use of rinse
jets, etc.
*». Install a p re-evaporator to reduce the volume of rinse
water.
5. Feed the condensed rinse water to the acid recycle and iron
recovery plant.
6. Seek other rinse water treatments as an economic alternate.
B. Ferrous Sul fate Hep tahyd rate
1. Fitzsimons should not attempt to enter the chemical market
on a "commercial" basis in order to move the ferrous sulfate.
The investment required in further processing equipment,
packaging equipment, establishment of engineering and sales
capaci 1 ities, etc. would far exceed any gross profit that
could be realized in the sale of such a relatively small
output (110 tons per month).
2. Fitzsimons should actively follow the nine prospective cus-
tomers who have testing and sampling programs currently under
way. It is entirely within the realm of possibility that one
or several of these firms and/or cities will be interested in
absorbing at least part of the output.
3. If none of the current testing programs result in any action,
lists of chemical distributors and all city water and sewage
facilities within a 75 mile area should be compiled, and
each party on the list should be contacted either by phone
or letter, and followed up with a sample and chemical analysis
of the material. Whether or not the material can be effect-
ively used in a process is usually known only after tests are
run.
C. Economics
1. The plant should be operated at 1.2 cubic meters/hour.
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SECTION III
INTRODUCTION
A. The Magnitude of the Problem; Number and Geographical Distribution
of Pickling Plants
The problem of the disposal of spent pickle liquor is widespread through-
out the steel industry, especially in plants where finishing operations
such as cold-rolling, drawing, extrusion, and surface coatings are
employed. Large primary iron and steel producers may carry out inte-
grated operations through such finishing steps as cold-rolling, wire-
drawing, galvanizing, tin-plating, extrusion, etc., all of which require
at some stage surface cleaning by pickling. There are numerous noninte-
grated smaller plants throughout the country which convert hot-rolled
steel procured from primary finishers to some finished produce (cold-
rolled rods, wires, bars, coating sheets, etc.) by processes involving
preliminary pickling. Figure 1 shows the geographical distribution of
steel plants with 20 or more employees in the United States which
perform such operations. One hundred and sixty nine plants are shown
under the category SR Steel works and rolling mills—standard industrial
code (SIC) 3312 with most of them employing 500 or more. From a review
of the types of operations specified for these plants it is estimated
that perhaps 100 of them do some kind of pickling. There are 92 plants
shown in the category WD (steel wire drawing and nails--not integrated,
SIC 3315). These may or may not do pickling, depending on the nature
of the starting material. It is believed, however, that many of these
plants use hot rolled raw materials and consequently must incorporate
pickling in their process. Category CR (cold steel finishing mills--not
integrated, SIC 3317) including the Fitzsimons Steel Company consists of
88 plants throughout the country. It is believed that acid pickling is
the general practice in this segment of the industry. The plants in the
category PT (steel pipe and tubes, not integrated, SIC 3317) of which
there are 157 in the country also may or may not pickle, depending on the
type of raw material and on the uses for their product. It is believed,
however, that the majority of the pipe and tubing plants in the category
G (galvanizing and other coating, SIC 3*»79) also may or may not pickle,
depending on the type of raw material. It is believed, however, that
many of these, possibly up to one half, do some form of acid pickling.
Figure 1 indicates only those plants employing 20 or more personnel. In
addition to these, there are many smaller plants, with less than 20 em-
ployees in each of the designated categories, many of which also may
produce waste pickle liquor.
B. Estimate of the Pollution Load Due to Sulfuric Acid Pickling
Operation
According to the FWPCA estimates (1967) the waste load generated by sul-
furic acid pickling plants in 19&? would contain about 225,000 tons of
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NEW ENGLAND
SR-5, WD-28,
CR-14, PT-2,
PACIFIC
SR-15, WD-8,
CR-7, PT-24,
G-22
MIDDLE
ATLANTI
R-55
R-26, PT-43
G-36
VEST NORTH CENTRAL
SR-3, WD-0, CR-0,
PT-11. G-9
AST NORTH
MOUNTAIN^
SR-3, WD-0, CR-0,
PT-3, G-6/
WD-25
CR-39,' PT^SO
G-69
J" ~ ~ -1- -
ST SOUTH
CENTRAL
WEST'SOUTH CENTRAL
SR-7T
WD-2,
CR-0,
PT-12,
G-7
Standar
Industrial
Code No.
Legend
Steel Works § Rolling Mills ^ 3312
Steel Wire Drawing § Nails, not integrated 3315
Cold Steel Finishing Mills, not integrated 3316
Steel Pipe and Tube, not integrated 3317
Galvanizing § Other Coating 3479
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free sulfuric acid and about £30,000 tons of ferrous sulfate. These
estimates are consistent with later data which show that the sulfuric
acid consumption by the steel industry in 1968 was about £00,000 tons.
Calculations based on the consumption figures and on typical analyses
of spent pickle liquors indicate that about 200,000 tons of free sul-
furic acid and close to 900,000 tons of ferrous sulfate were discharged
from pickling plants in 1968.
On an average, in 1968, 85 percent of the sulfate components--about
200,000 tons of free sulfuric acid and about 700,000 tons of ferrous
sulfate—were discharged in the form of concentrated spent pickle
liquor, containing about 60 grams/liter of free sulfuric acid and about
250 grams per liter of ferrous sulfate. The remainder--15 percent, or
about 30,000 tons of free sulfuric acid and about 125 tons of ferrous
sulfate—was sent to waste in rinse water streams, considerably more
dilute than the spent pickle liquor. The composition is dependent on
the dragout rate and the quantity of rinse water used which could be
expected to vary considerably depending on the type of material being
pickled and plant practice. Typically, rinse water contains sulfuric
and ferrous sulfate in the concentration range of a few hundred parts
per million to a few grams per liter.
From the plant distribution data shown in Figure 1, the greatest con-
centration of plants engaged in pickling exists in the most urbanized
areas of the country, particularly in the East, North, Central, and
Middle Atlantic States. It is in these areas that the maintenance of
adequate water quality for public water supply, recreation, aquatic life,
and aesthetic value is becoming increasingly difficult.
Despite the fact that other methods of surface cleaning (such as hydro-
chloric acid pickling, shot blasting, etc.) may supplant to some extent
the sulfuric acid pickling process, there is no indication that the
quantity of waste free sulfuric acid and ferrous sulfate will be reduced
below its present level. On the contrary, estimates made by FWPCA (196?)
indicate that, in 1972, the sulfate waste load from steel mills will be
about 10 percent greater than in 1968.
C. Processes Available for Treating Sulfuric Acid Pickle Liquor
The methods or processes available for the disposal of spent sulfuric
acid pickle liquor may be classified as follows:
(1) Disposal of the untreated liquor either to deep wells,
abandoned limestone quarries, or evaporative lagoons; or
by controlled flow (proportionation) to natural water
bodies. This last, which was in wide use in the industry,
is now being phased out by tighter government restrictions
and enforcement.
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(2) Neutralization and the precipitation of iron by lime with
or without oxidation. This process requires subsequent
impounding of the liquor to permit solids-liquids separation.
Acceptably pure aqueous effluents can be obtained but the
process requires relatively large land-areas for lagooning
and results in the formation of a sometimes troublesome
sludge. Large steel companies and contract disposal com-
panies have employed this process. While the process requires
little capital investment, operating costs may be high.
(3) Various types of processes (differential solubility, evapor-
ation, refrigeration) all aimed at selectively removing
ferrous sulfate from the spent liquor and recovering free
sulfuric acid. The Keram-Chemie-Lurgi process, which
Fitzsimons has adopted, is one of several commercially de-
veloped processes of this type. The advantages of such pro-
cesses are that they completely "bottle up" the plant,
producing no water-borne pollutants, recover a significant
proportion of the free sulfuric acid still present in spent
liquor, and produce a ferrous sulfate by-product, which, under
certain circumstances, may constitute an economic credit.
(1*) Electrolytic-type processes to recover high-purity iron and
sulfuric acid. Such processes have received considerable
attention and have been rather thoroughly developed. As far
as is known, the electrolytic processes are not being used
comme re i a 11y.
(5) Miscellaneous methods which involve the conversion of the
ferrous sulfate content to iron oxide, ferric sulfate, ferric
chloride, or sodium sulfate by various chemical methods. None
of these has achieved commercial success.
The problem of the disposal of spent pickle liquor has been formidable,
so much so that in recent years attention has been focused on hydro-
chloric acid pickling. The spent liquor from hydrochloric acid pickling,
unlike that from sulfuric acid pickling, may be processed to yield a
high-grade iron oxide product and to regenerate the acid. Regenerative
hydrochloric acid pickling processes are now in commercial operation at
a number of the larger steel plants in the United States. A thorough
assessment of their economic and technical advantages and disadvantages
has yet to be completed. More widespread use of this process is antici-
pated, but it will probably not be economic for the smaller plants
generating less than 10 to 20 gpm of spent liquor.
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SECTION IV
THE PROBLEM AT THE FITZSIMONS STEEL PLANT
The Fitzsimons Steel Company of Youngstown, Ohio produces about 40,000
tons per year of cold-rolled steel bars, rods, and coils from purchased
hot-rolled stock. In the cold-rolling processes, preliminary acid
pickling is required to remove mill scale, rust, dirt, grease, etc.,
from the feed stock. The Company operates two pickling lines--one for the
bars, the second for the coiled rods. Figure 2 is a diagram of the
operation.
As shown in the diagram, the major waste is the combined spent liquors
from the two pickling lines. This amounts to approximately 55,000 gallons
per month of a solution containing up to 5 percent free sulfuric acid and
about 0.8 pound per gallon of iron, dissolved as iron sulfate. This is
equivalent to a monthly pollution load of about 17 tons of free sulfuric
acid and 22 tons of iron. The combined waste solution is proportioned
at a controlled slow rate into a nearby run which, in turn, discharges
into the Mahoning River.
On the basis of comparative tonnages, considering that the total tonnage
of cold rolled bars and rods in the United States is approximately
20,000 tons per year and that the Fitzsimons production \s ^0,000 tons
per year—the total pollution load chargeable against just this segment
of the industry is annually about 100,000 tons of free sulfuric acid and
about 130,000 tons of ferrous sulfate. As can be seen from Figure 1,
this segment of the industry is concentrated in the populous areas of
the country.
Studies made by the State of Ohio Department of Health have indicated
that controlled discharge without neutralization and precipitation of
spent pickle liquors is incompatible with its aim of maintaining water
quality in the Mahoning River and, as indicated previously, directed the
Fitzsimons Company to seek other methods of treatment and disposal.
A. Steps Taken by the Fitzsimons Steel Company
In March, ]$6B the State suggested that the Company investigate the possi-
bility of contracting with some outside organization to haul away the
waste pickling acid, neutralized and disposed or in such a fashion that
harmful pollution would not occur. Fitzsimons explored this suggestion
and concluded that the cost of disposal by contract haulage and neutral-
ization would be economically prohibitive.
Company executives also surveyed a number of other possible disposal
methods and after careful consideration, involving inspection tours to
operating commercial-scale European installations, decided that the Keram
Chemie-Lurgi Sulfuric Acid Regeneration Process appeared to be the most
suited for their needs.
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Rod Line
Coiled Rods
Make-up
Sulfuric
Acid
(78% wt./wt-.)
Bar Line
Bars
Pickling Tank
9 ft. long
7 ft. wide
6 ft. deep
2500 gals.
15 Tons
per Month
24 Tons
per Month
Pickled Steel to
Rinse, Lime Coat-
ing and Cold Drawn
1
Rinse Water
to Waste
Two Pickling
Tanks; Each:
36 ft. long
3'-6" wide
I1-6" deep
1000 gals.
T
Pickled Steel to
Rinse, Lime Coat-
ing and Cold Drawn
I
Rinse Water
to Waste
f
Spent Liquor
One Tank per Week
11,000 gals./month
I
Spent Liquor
Two Tanks per Day
= 44,000 gals./month
J
Combined Spent Liquor
= 55,000 gals./month
Up to 5 Percent Free H2S04
Up to 23.4 tons/month Fe
I
Storage Tank
Controlled Discharge to
Mahoning River
FIGURE 2 Outline of Fitzsimons Batch Pickling Operation
Prior to Acid Recycle and Iron Recovery Process
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After having obtained approval of the process by the State of OhJ6
Department of Health in February, 19&9, the Company undertook nego-
tiations with Keram Chemie for the purchase of a treatment plant.
B. Benefits from the Acid Regeneration
The installation and successful operation of this plant has a twofold
effect. Most importantly, it completely eliminates the pollution load
due to spent pickling baths that Fitzsimons has been sending to the
Mahoning River over the past 50 years, a load which within the next few
years would be even greater. Secondly, certain economic advantages were
realized from the recovery of sulfuric acid and possibly the sale of
by-products. These advantages have been shown to be real and significant;
thus, a practical and economical avenue to the abatement of a serious
pollution problem has been demonstrated, and a stimulation provided for
other companies to follow suit.
The Keram Chemie-Lurgi Sulfuric Acid Regeneration Plant has been gen-
erally described in various Keram Chemie Corporation brochures. A flow
and equipment diagram of the operation as it is applied to the Fitzsimons
waste is shown in Figure 3. Figure *4 is an overall view of the Acid
Recycle and Iron Recovery Plant. Figures 5 through 9 present the various
components of the system.
Although no Keram Chemie-Lurgi plants have been installed in this country,
the process is being applied successfully in Germany, France, Denmark,
and South Africa. At least 11 Keram Chemie-Lurgi installations are not
in operation, treating the waste liquors from steel mills producing wire,
strip, bars, pjpes, and other shapes at capacities ranging from 2000 to
10,000 tons per month. Production capacity of the Fitzsimons Steel Company
is about 4000 tons per month.
Keram Chemie has guaranteed the plant to operate at the capacity about
50 percent in excess of Fitzsimons present pickle liquor output and has
also guaranteed the serviceability of materials, and operability of the
plant. The contract between Keram Chemie and Fitzsimons was on "turn-key"
basis and Keram Chemie installed, started up and brought the plant into
proper operation.
10
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I Bar Pickling 1
Rod Pickling [
Spent Liquor
44,000 gals./month
(Batch Feed)
13% H?S04
8% .Fe
Spent Liquor
=11,000 gals./month
(Batch Feed)
13% HnSO^
8% Fe
- _*
Equalization Tank
For Continuous Feed
To Acid Recycle Plant
Steam
(900 Ibs./hr.)
15 psi.
i
Steam Jet
Ejector
Stainless Steel
316 gals./hr.
'(1.2 M3/hr.)
13% H7SOA
8% Fe
Cooling
Crystallizer
Vertical,
Ruobei
Steel
\
Cooling Water
7200 gals./hr.
I
Condensing Units,
Main Condenser,
Two Auxiliary Con-
densers in series
with Auxiliary
Ejectors, Rubb'er-
Ixfted-£t_ee 1, In-
serts and Baffles
Stainless Steel
Slurry
Mother Liquor
and Ferrous
Sulfate Hepta-
hydrate Crystals
\
Condensate plus
Cooling Water
to Waste or Reuse
(Continued on page 13)
FIGURE 3A Equipment Diagram of Acid Recycle Plant
11
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0
(Continued from page 12)
Centrifuge Feed Tank
Rubber-lined Steel
Centrifuge
Stainless Steel
99.561
..Ferrous Sulfate.
Heptahydrate
115 Ibs./hr.
To Sale, Dis-
.posal, or pos-
sibly further
Processing
Mother Liquor
12% H7SOA
51 Fe
302 gals./hr.
(1.15 M3/hr.)
Storage Tank
Rubber-lined Steel
Recycled
to
Pickling
Aux i1i ary Equipment:
I Cooling Water Pump
3 Acid Pumps
(for liquor)
1 Instrument and Con-
trol Panel
Process Piping
(in-plant)
Production Specifications:
71 Tons Steel per Shift
2 Shifts per Day
5 Days per Week
50 Weeks per Year
FIGURE 3B. Equipment Diagram of Acid Recycle Plant (cont'd)
12
-------
FIGURE 4
Overall View of Acid Recycle and Iron Recovery Building
'
-------
FIGURE 5
Instrument Panel of Acid Recycle and Iron Recovery System
14
-------
••••
•
a
• i
: •
.
•
j
•-
tt
a
•-.
c
-
1
-------
0
Q> —
3 C?
Q- C
30
o m
O
O ***J
3
UB
o
-i
ID
rt
01
C
-------
FIGURE L
Steam Ejectors with Condensing Units
17
-------
n
n
D
H
3
I .
,-
n
3
ffl
01
3
Q
n
n
ID
n
a
-------
SECTION V
BASIC DESIGN CRITERIA
In designing systems for the recovery of ferrous sulfate and sulfuric
acid from spent pickle liquors from continuous pickling lines and other
pickling processes, it is essential to know the solubility of ferrous
sulfate in such liquors at various temperatures and acid concentrations.
For example, (1) The solubility at low temperatures is necessary when
the spent liquor is cooled to extract ferrous sulfate heptahydrate.
(2) The solubility at high temperatures and high acid concentrations
is necessary when the liquor is evaporated to high acid concentration
to extract ferrous sulfate monohydrate. (3) The solubility at low acid
concentrations and high temperatures is necessary to ensure that ferrous
sulfate does not crystallize in the pickling tanks.
Tables 1 to 3 show the experimental work of Bui lough, Canning, and
Strawbridge for both the monohydrate and heptahydrate forms of ferrous
sulfate. The transition points are shown in Table k.
Linear interpolation of the data is shown in Tables 5 and 6. The results
were then plotted in Figure 10.
The obvious conclusions are:
(1) The higher the acid concentration the lower the solubility
of ferrous sulfate heptahydrate and therefore the greater
the recovery.
(2) Since the Regeneration Plant operates around 6°C at acid
concentrations less than 20%, only the heptahydrate will
be formed.
19
-------
TABLE 1
Ferrous Sulfate Monohydrate Dissolution
in Sulfuric Acid Solutions
(0°C - 60°C)
0°C 55°C
)j. H2SOi,
°/Tw/W* % W/W* % W/W* % W/W*
38.05 2.72 1.50 33.ftO
ftl.20 2.80 3.ftO 31.30
fth96 2.86 ft.35 30.ftO
ft3.21 2.32 ft.75 29.70
ft5.83 1.51 9.10 25.85
57,30 I.10 - 11.05 23.90
53.0ft 0.0ft 21.80 15.35
30.80 8.35
ft2.76 3.ft6
25°C 60°C
H2SO^ FeSOj. H2s°2i FeSOL
% W/W* % W/W* % W/W* % W/W*
21.11 12.85 1.35 32.30
38.ftO 11.00 1.97 31.70
30.05 10.30 2.35 31.10
31.37 9.05 ft.85 28.75
3ft.ft5 7.05 6.05 27.20
37.80 ft.81 S.ftO 25.ftO
ft2.28 2.98 10.38 23.52
ft7.ft7 1.29 17.60 18.12
21.95 15.02
25.50 12.52
32.87 7.80
38.96 ft.56
ft5°C ft6.63 1.97
5ft.58 0.65
H-SO. FeSOi, 59.56 0.37
% W/W* % W/W^f
13.70 22.65
15.90 21.01
19.75 17.75
22.00 15.65
25.75 12.65
* % weight/total weight
20
-------
TABLE 2
Ferrous Sulfate Monohydrate Dissolution
in Sulfuric Acid Solutions
(80°C - 100°C)
80°C 100°C
FeSOi, H2SOj. FeSO/,
% W/W* % W/W* % W/W* % W/W*
1.60 26.60 2.97 18.70
2.00 26.18 5.79 17.98
2.45 25.60 8.24 17.62
3.75 24.60 11.04 17.28
4.50 23.90 13.28 16.78
f:.8B 22.10 16.08 15.98
8.0t 21.40 19.10 14.80
13.G8 18.50 21.17 14.00
20.30 15.00 28.38 9.95
26.40 11.48 35.94 6.60
30.66 8.75 42.19 3.83
37.75 5.35 44.97 2.99
44.83 2.73 50.85 1.62
51.57 1.13 56.31 0.92
56.00 0.65
* % weight/total weight
21
-------
* % weight/total weight
25°C
TABLE 3
Ferrous Sulfate Heptahydrate Dissolution
In Sulfurlc Acid Solutions
0°C 45°C
H2SO^ FeSOj, H2SOfc
% W/W* % W/W* % W/tf* % W/W*
0.70 13.41 0.80 30.55
6.7^ 10.90 3.70 28.50
12.17 8.76 7.^0 26.41
16.92 6.98 10.31 25.42
23.46 4.88 12.65 24.60
29.41 3.24 15.70 22.81
33.40 3.02 18.12 21.60
38.58 2.67
41.53 2.75
43.62 2.92
47.90 2.08
H2SO. FeSO/.
% W/W* % W/W*
0.60 22.51
2.92 21.05
6.42 18.90
16.23 14.52
24.70 11.48
28.00 10.71
32.38 9.80
34.80 8.70
36.65 6.91
22
-------
TABLE 4
Transition Points of Ferrous Sulfate
In Sulfuric Acid Solutions
* % weight/total weight
23
Temperature H2^^4 er
or % W/W* % W/W*
I/
0 ^2.2 2.7
25 30.0 10.4
kS 13.0 24.3
-------
TABLE 5
Ferrous Sulfate Monohydrate Dissolution
In Sulfuric Acid Solutions (Interpolated)
H-SO. Temp.
% W/W* °c
0 25
2.5
5
7.5
10
12.5
15
20
25 11.86
30 10.32
35 6.68
to 2.78 3.91
45 1.76 2.09
50 0.77
% W/W*
45
21.76
17.52
13.25
55
32.39
29.48
27.26
2*t.95
22.1k
20.76
16.7&
12.86
8.97
6.63
4.58
60
30.96
28.55
26.09
23.88
21.93
20.06
16.41
12.87
9.64
6.67
4.21
2.52
1.41
80
25.56
23.52
21.74
20.44
19.19
17.89
15.16
12.28
9.17
6.67
4.51
2.68
1.50
100
18.18
17.72
17.41
16.95
16.29
14.45
11.84
9.23
7.01
4.80
2.98
1.81
The above values were interpolated from Tables 1 and 2
/
* % weight/total weight
-------
TABLE 6
Ferrous Sulfate Heptahydrate Dissolution
In Sulfuric Acid Solutions (Interpolated)
H2$0. Temp. ^
% w/w* °c % w/w*
0 25 kS
2.5 12.66 21.31 29.34
5 11.62 19.77 27.76
7.5 10.61 18.1(1 26.37
10 9.61 17.30 25.52
12.5 8.63 17.15 21*.65
15 7.70 15.06 23.22
20 5.99 13.17
25 k.k6 11 .M
30 3.21 10.29
35 2.91 8.51
kQ 2.59
k5 2.6k
The above values were interpolated from Table 3
* % weight/total weight
25
-------
o
rn
o
O
c
01
rt
n
n
o
C
(/I
u,
E.
-h
C
n
SI
35-1
30-
FeS04'7H20
25-
Si
o
20-
15-
FeS04'H20
10-
5-
0
10
20
30
40
50
60
70
80
90
100
TEMPERATURE, °C
-------
SECTION VI
RINSE WATER STUDIES
Rinse water studies began with a procedure for measuring the volume
dnd rates of rinse water at the sources. There are three main sources:
1) Hose rinsing «t the bar and coil mill; 2) drag-out from pickling;
and 3) cooling water from the acid recycle plont. It is estimated that
the dragout is about 70 gallons/hour (based on 15.8 tons steel/day);
hose rinsing is about 228 gal long/hour; and cooling water is 3750 to
**950 gallons/hour. The rates for the hose rinsing and cooling water
were obtained from field data. Table 7 summarizes the rinse water use.
Measurements of the total iron, ferrous iron, ferric iron and sulfate
concentration were made and are summarized in Figures 11 to \k. These
figures illustrate the peak, variation and average of free pollutants
with and without the acid recycle plant in operation. The pollution^!
load prior to treatment is summarized in Table &.
Having determined the volume and composition of the rinse waters we
shall examine the various processes capable of eliminating the pollutions
load. The present system is shown as a mass balance diagram in Figure
15.
In order to eliminate the pollutions! load due to rinse water we shall
examine the following alternatives.
(a) Multi-stage countercurrent rinsing in low volume tap rinse
water with return to acid recycle plant.
In this case we must consider the following: 1) the spent pickle
liquor rate cannot increase; for if it did we would have an excess of
recycled liquor; 2) the steam heat to the pickle tank Causes dilution
and should be eliminated; 3) the drag-out of 70 gal/hour could be reduced
by allowing more time for the pickle liquor to run off the bars and
coiIs.
Thus, let us examine the following system: 1) eliminate steam heating
with a heat exchanger; 2) reduce the drag-out; 3) reduce the amount of
rinse water use by more efficient rinsing, i.e. use multi-stage counter-
current rinsing, efficient jets, etc.
The proposed mass diagram is shown in Figure 16. Note that only k
gal/hour of rinse water may be used, and the pickling tank is heated by
a heat exchanger.
(b) Multi-stage countercurrent rinsing with resulting rinse water
being concentrated by pre-evaporation and then fed to the acid
recycle plant.
27
-------
The system Is the same as above except that we could allow more rinse
water to be used. However the pre-evaporator output to holding tank
1 can only be k gallons/hour. Commercial pre-evaporation units are
avallable.
(c) Neutralisation of the present dilute rinse waters followed
by aeration and sludge reelrculation to oxidize ferrous
i ron.
A facility to dispose of these rinse waters was designed by ARMCO Steel
Corporation, Middletown, Ohio (1971). This process utilizes limestone
for neutralization plus aeration and sludge recirculation to oxidize
ferrous iron and form soluble calcium chloride. Hydrochloric acid was
used as the pickler instead of sulfuric acid. Operating costs were
2^.0^/1,000 gal rinse water or A.38
-------
TABLE 7
Summary of Rinse Water Use
Day
Mon
Tue
Wed
Thur
Frf
Total
Rinse Volume
Gallons
Bar Coil
676
659
821
640
731
3527
372
484
500
650
8fc3
2889
Rinse Period
Hours
Bar Coil
5.73
6.35
7.13
6.27
6.93
17
82
6.33
5.37
6.67
Rinse Rate
Gallons/hour
Bar Coil
118
32.41 24.36
115
102
106
109
171
126
79
121
132
119
Avg. flow for Bar Mill
Avg. flow for Coil Mill
Drag-out for Bar and Coil Mill =
Total Rinse Water Flow with
No Cooling Water from Acid
Recycle Plant
Acid Recycle Plant Cooling Water
Total Rinse Water Flow Including
Cooling Water from Acid Recycle
Plant
109 Gal/hr
119 Gal/hr
70 Gal/hr
298 Gal/hr
3750-4950 Gal/hr
4050-5250 Gal/hr
29
-------
100,000
10,000
s
ft
o
H
o
H
1,000
100
10
T
T
T
Peak due to pickling
tank discharge
3200 ppm.
Average value
without regenera-
tion plant opera-
tion.
172 ppm. Average value
with regeneration
plant operation..
Mon. Tues, Weds. Thurs. Fri.'
12/14/70 12/18/70
FIGURE 11 Total Iron Vs. Time For Bar Mill Rinse Water
30
-------
100,000
10,000
g 1,000
ft
ft
2;
o
t)
o
w
100
10
Peak due to pickling
tank discharge
2260 ppm. Average
value without _
regeneration
plant operation,
51 ppm. Average value
with regeneration plant
operation.
Mon. Tues. Weds. Thurs, Fri,
12/14/70 12/18/70
FIGURE 12 Ferrous Iron Vs. Time For Bar Mill Rinse Water
31
-------
100,000
10,000
2
§ 1,000
u
hH
(*
04
100
Peak due to pickling
tank discharge
122 ppm. Average value"
with regeneration plant
operation.
10
Mon.
12/14/70
940 ppm. Average value
without regeneration
plant operation.
Tues. Weds.
FIGURE 13 Ferric Iron Vs. Time For Bar Mill Rinse Water
Thurs. Fri.
12/18/70
32
-------
1,000,000
100,000
10,000
a,
1,000
100
Peak due to pickling
tank discharge
y-11,250 ppm. Average value
* without regeneration
plant operation.
3167 ppm. Average
value with regeneration
plant operation.
10
Mon. Tues. Weds. Thurs. Fri.
12/14/70 12/18/70
FIGURE 1**. Sulfate Vs. Time For Bar Mill Rinse Water
33
-------
TABLE 8
Rinse Water Pollution Prior to Treatment
Pollutant Concentration* Concentration** Pollutant Rate
Mg/1 Mg/1 Pounds/Hour
Total Iron
Ferrous Iron
Ferric Iron
Sulfate
3200
2260
9^0
11,250
172
51
~ 122
316?
7.95
5.61
• 2.34
28.0
* Acid Recycle Plant not in operation. Thus no cooling
water dilution
** Acid Recycle Plant in operation. Diluting cooling water
-------
Drag Out, 70 gals./hr.
t
1
Pickle
Tank "*
i
1
13% H2S04
9% Fe^
1
74 gals./hr. I
Steam Heat
1
Spent Pickle Liquor
316 gals
./hr. , 13% H?SOd
, (Batch) 9% Fe '
Holding
Tank
I
i
316 gals./hr.
1 "7 0 T T C* f~\
13% HoSO/i
9% Fe
Recycled Acid
312 gals ./hr .
14% H2S04
5% Fe
Hold:
f -.,
Lng ^
ik 302
II 12
E
Cooling Water
5000 gals./hr.
01 H2S04
01 Fe
\
Acid
Plant Cooli
5000
0% H;
0% Fe
r
FeS04'7H20
99.561
115 Ibs./hr.
gals ./hr.
!% H2S04
»% Fe
Rinse Water
228 gals./hr.
0% H?SO,
0% Fe *
i •
Unse
Tank
Discharge to River
298 gals./hr.
41 H2S04
3% Fe
Total Water
to River
5300 gals./hr.
0.23% H2S04
0.17% Fe
ing Water
.ver A^
gals./hr. j~~f
;S°4 /&
JlSf
J&y
Jjr
/SJjf
=i-Fp
T
10.3 gals./hr.
78% H2S04
(Sp. Gr. = 1.708)
FIGURE 15. Acid Recycle System with Rinse Water to Waste
35
-------
•K
O
• r-l
u
x
u
Drag Out, 70 gals./hr.
9%^Fe
Pickle
Tank
Rinse Water
.4 gals./hr.
0% H2S04
01 Fe
Rinse
Tank
Spent Pickle Liquor
316 gals./hr. 131 H2S04
(Batch) 9% Fe
Holding
Tank
I
Spent Rinse -Water
V74 gals./hr.
12%
8% Fe
Make-up Acid
_10.3 gals./hr.
78% H2S04
(Sp. Gr. = 1.708)
400 gals./hr,
15% H7SOd
8% Fe 4
Cooling Water
5000 gals./hr,
0% H2S04
0% Fe
Acid
Recycle
Plant
Holding
Tank
II
Water to River
5000 gals./hr.
0% H9SOA
0% Fe 4
FeSO 7H 0
99.56%
115 Ibs./hr
386 gals./hr.
19%
5%
H7SO
Fe
FIGURE 16 Acid Recycle System Treating Rinse Water
36
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SECTION VII
MARKET SURVEY OF FERROUS SULFATE
Because up to 70 tons/month of ferrous sulfate is produced (presently
18.5 tons/month) and since this by produce is not used by Fitzsimons
Steel in their process a market survey was conducted to determine
possible uses and outlets of the by-product. The following pages
summarize the market survey. Additional information can be found in
the appendix.
37
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SUMMARY OF MARKET SURVEY
Following Is a brief recapitulation of the major findings of the
study:
1. Approximately 200,000 tons of ferrous sulfate are produced
nationally each year. Of this total, only 55%-65% is actually
sold into the open market.
2. The dollar value of the market for commercially-produced
ferrous sulfate amounts to approximately $1 million annually.
Growth over recent years has been moderate.
3. Current production capacity "in-place" for commercial grades
of ferrous sulfate amounts to 355,000 tons annually—consider-
ably above the tonnage actually produced and sold.
k. The market is actually in a glutted state—and prices have
wavered over the years in reflection of the excess production
over market-absorbing ability.
5. Major commercial producers include but are not limited to:
National Lead Co.; Pfizer, Inc.; Cosmin Co.; American Cyanamid
Co.; and Steel Chemical Co.
6. Major end-use markets for the commercially-produced material are:
iron oxide pigments — 55%; ferrites — 30%; water and/or sewage
treatment —• 5%; and other applications — 10%. (The percentages
represent tonnage — not dollars.)
7. In addition to the ferrous sulfate produced commercially, an
additional 2.7 million tons is generated annually as by-product
from the manufacture of steel and titanium dioxide. This material
is generally is slurry form — impure and dirty. Most of it Is
being "disposed of" by the companies involved — either through
direct dumping or deep well pressure injection. Pollution
officials are putting a stop to dumping procedures — with the
result that steel companies and producers of titanium dioxide
are desperately seeking methods of legitimate disposal.
8. The Fitzsimons ferrous sulfate generated as a by-product from the
Keram Chemie-Lurgi process is considered to be far superior in
quality and physical characteristics to the spent pickle liquor-
types of ferrous sulfate currently being generated by some mills.
38
-------
9. Usage of ferrous sulfate in the local market (75 mile radius
around Youngstown) is currently negligible. There is no
potential in iron oxide pigments since the major paint companies
generate most of their own needs when they manufacture titanium
dioxide for use as a "filler" in their paints; the only substantial
fertilizer producer in the area no longer uses the material in
their blends. Therefore, the only realistic "potential" markets
are the water and sewage treatment plants in the various cities
in the trading area.
10. During the course of the survey, nine companies and/or cities were
furnished with physical samples of the Fitzsimons material along
with a chemical analysis. A full listing of these nine--and the
current status of their testing appears in the appendix.
11. The best current prospect for a portion of the material is the
Mahoning Valley Sanitary District for the treatment of water.
12. Chemists and technical people "call the shots" on whether or not
the material can be used. This hurdle must be crossed before
purchasing negotiations even begin.
13. Normal prices for ferrous sulfate heptahydrate are $20-$40 per ton
for high-grade, bagged material—shipped FOB carload. Estimates of
a "logical" price for the Fitzsimons product are in the $10 per ton
range, delivered.
The net of the situation is this: if this was a market that Fitzsimons
was considering getting into from a purely commercial standpoint, the
answer would be obvious—don't do it. It is over-produced already.
However, Fitzsimons is not in the business "voluntarily". Fortunately,
their by-product material is considered significantly better than the
by-product of other sulfuric acid recovery systems by those that have
seen and tested i-t. As a result, even though there is no open "demand"
for the product within their trading area, it 5s considered quite likely
that the material can be successfully disposed of—either at a profit,
or certainly at no loss to Fitzsimons. This is because the material is
of a unique grade and purity. The only way that ultimate users will be
located, however, is through a testing program. The nine tests currently
under way could very well result in some "live" prospects for the material
If not, then an all-out sample and testing program should be instituted
with all chemical distributors, and water and sewage plants within the
trading area that have not already been contacted.
39
-------
SECTION VIII
EXPLORATORY PROGRAM TO EVALUATE THE CONVERSION
OF FERROUS SULFATE TO OTHER PRODUCTS
One of the objectives of this study was to determine possible con-
version of ferrous sulfate heptahydrate. As outlined in Section VII -
Market Survey, there are markets for ferrous sulfate as produced, namely,
the Mahoning Valley Sanitary District which treats water for a potable
water supply of 30 MGD and the City of Youngstown Waste Water Treatment
Plant. A chemical analysis of the recovered salt was performed in
order to evaluate the quality of the product. This analysis was made
for two reasons: (1) establishing the unit price of the product; and
(2) using this information as input data for conversion processes
A. Chemical Analysis of the Recovered Ferrous Sulfate Heptahydrate
Sampling:
Equal amounts of thirteen samples were mixed together using standard
sectioning techniques. The appearance of the samples was fairly uniform
and quite clean looking. There were occasional lumps which appeared
gray instead of the light green-blue color associated with the general
sample. The time of exposure to the air was kept as short as possible.
Ferrous Ion Analysis:
The ferrous content of the sample was determined on three separate
samples by dissolving a weighed amount of sample in deionized water and
directly titrating with a standardized potassium permanganate solution.
The results were 19.73 ± 0.07%.
Ferric Ion Analysis:
The ferric ion content was determined by difference. A total iron
analysis was performed by dissolving three weighed samples in deionized
water, reduction of any iron in the ferric state with stannous chloride,
destruction of excess stannous chloride with mercuric chloride and
titration with the standard potassium permangana solution. The results
indicated 0.0*1% ferric ion. This low percentage was qualitatively
checked by addition of a potassium thiocynate solution to a 5% solution
of the sample. A very slight red color resulted. Addition of a small
amount of ferric solution resulted in a blood red color. The conclusion
is that there is very little ferric ion in the sample.
Sulfate Ion Analysis:
The sulfate ion was analyzed for by precipitation with barium chloride,
quantitative filtration and ignition to a dry barium sulfate residue.
-------
This is a standard way to analyze for sulfate and the results of three
analysis gave a sulfate content of 3^.00 i 0.03%.
Total Water Content:
TheQwater content was determined by vacuum drying the sample at
325 C for two hours. The results of three separate analysis gave a
content of ^5.7** + 0.02%. This result may be somewhat low as the last
trace of water is very difficult to remove from material such as this.
Chloride ion Analysis:
The upper limit of the chloride ion content was determined by a standard
addition technique. A 5% solution of the sample was treated with a 1%
solution of Silver Nitrate. There was no precipitation of AgCl or any
indication of a precipitate, opalesence. Addition of a trace of chloride
amounting to 0.005% of the sample weight gave a noticeable cloudiness
of AgCl precipitate. It was, therefore, concluded that the chloride
content of the sample was less than 0.005%.
Insoluble Residue:
The insoluble residue was determined by filtering a solution of a weighed
amount of the sample through a porous glass crucible and weighing the
residue. This was done for three separate samples with a result that
the insoluble residue is 0.01%.
pH of a 5% Solution:
The pH of a 5% solution was determined and was found to be 3.6 comparable
to a solution of commercial ferrous sulfate.
Phosphate Ion Analysis:
A very sensitive test for phosphate is the development of a blue color
with ammonium molybdate solution. Tests indicate no color formation
with this test solution and the conclusion is that there is no phosphate
in the sample.
Manganese Analysis:
The manganese content was determined by standard addition techniques
using the oxidation of manganous ion to permanganate ion which is highly
colored as the basis for the test. The result was a manganese content
of 0.05%.
Copper Ion Analysis:
The copper ion was determined by the extraction of copper dithizone
complex into carbon tetrachloride. This test showed a very low almost
41
-------
undetectable amount of copper in the sample. The content was less
than 0.005%.
Zinc Ion Analysis:
The zinc ion was determined in the same manner as the copper ion and
the results showed a zinc ion content of less than 0.02%.
The sample which was analyzed is quite pure ferrous sulfate. The
theoretical percentage for ferrous ion is 20.08% compared to the 19.73%
found. The theoretical value for sulfate ion is 3^.53% compared to the
value found of 3*t.00%. However, the ratio of ferrous to sulfate weights
is ,5817 to 1.000 theoretically and .5815 to 1.000 actually. The
conclusion is that the material is FeSO^ with slightly more than seven
(7) waters of hydration. In other words, the sample is slightly wet
FeSOit.7H20.
The trace analysis compared quite favorably with commercially available
"Certified Reagent Grade" ferrous sulfate. There is no indication of
contamination by calcium ion or sodium ion as evidenced by the negative
results of a flame test.
B. Conversion To Other Products
1 Fused Magnetite and Sulfuric Acid
Treadwell Corporation (1972) has developed a system for converting
ferrous sulfate into fused magnetite and a gas which can be converted
into 20 percent acid by wet oxidation. They have developed a very com-
pact furnace unit which can be skid mounted and operated at a very high
capacity. The operating temperature is 2800°F. With a very intense
flame of fuel, oxygen, and ferrous sulfate, the iron oxide is melted
and collected to be trapped from a hearth into a ladle or floor mold.
2 Ferrous Sulfate Roasting - Contact Sulfuric Acid Plant
A. E. Demhiltz of Singmaster and Breyer in an article entitled "Profit-
able Pickle Liquor Regeneration" (I960) discusses a process expected
to operate under $15.00/ton of sulfuric acid which converts ferrous
sulfate to 90 percent sulfuric acid. The washed ferrous sulfate is
continuously fed to a rubber conveyor belt and carrie to the top of a
multiple hearth furnace. Coal fines and sulfur are added to the wet
cake to insure proper roasting conditions and that sufficient sulfur
bearing gas are available to the acid plant. A small package contact
sulfuric acid plant equipped with standard scrubber, mist precipitation,
heat exchangers and converter receives the hot gases from the cyclone
dust collector. The gases are water quenched, precipitated, and dried
in a packed tower with sulfuric acid before passing to three heat ex-
changers. Sulfur dioxide with excess oxygen is converted in the converter
to SO} and eventually absorbed by H2SO^ to make 90 percent acid.
42
-------
TABLE 9
Analysis of a Salt Sample
Identified as "Ferrous Sulfate Heptahydrate"
Ferrous Iron (Fe++) 19.73%
Ferric Iron (Fe++-0 O.OV/0
Sulfate Ion (SOV-) 3^.00%
Water (H20) 45.7^%
Chloride Ion (C1-) Less than 0.005%
Insoluble Residue . . 0.01%
Phosphate Ion (PO^—) . . . 0.000%
Manganese Ion (Mn ++) 0.05%
Copper Ion (Cu++) Less than 0.005%
Zinc Ion (Zn++) Less than 0.02%
Total Material Accounted for 99.56%
pH of s 5% solution 3.6
43
-------
TABLE 10
Comparison of Recovered Salt With
Theoretical Ferrous Sulfate Heptahydrate
Molecular % %
Weight Theory Analysis
Ferrous ion (Fe++) 55. SV 20.08 19.73
Sulfate ion (SOj,--) 96.06 3^.56 34.00
Water (H20) 126.112 ^5.36 kS.lk
Other 0.00 0.09
278.012 100.00 99.56
44
-------
SECTION IX
ECONOMIC ESTIMATES
A. Capital Costs
During the entire project accurate records were kept of all expenses
incurred for the Regeneration Plant, and are summarized in Table 11.
In summary the costs are as follows:
Development $ 15,953.00
Construction 175.757.72
Total Capital Costs 191,710.72
The total capital costs were amorftized over a 15 year period using
an interest at 6%. Based on these facts, the yearly capital cost was
$19,738.5*4.
B. Normal Operation
During the period January 1, 1971-June 15, 1971 the acid recycle was
operated under normal conditions. From the data of Tables 11 and 18
and unit costs obtained for utilities, operating benefits and costs
were calculated as shown in Table 12. The results are summarized as
fol lows :
Normal Operation (Salt asset)
Operating Costs 15.59$/hr
Operating Benefits 5.S3$/hr
Net Cost 9.66$/hr 38,6AO$/hr
Capital Cost 19.739$/yr
Total Cost 58,399$/yr
The above assumes that the ferrous sulfate is an economic gain. However,
due to the overproduction of the product, it should be considered as a
liability. The results are summarized below and shown in Table 13.
Normal Operation (Salt liability)
Operating Costs 15.93$/hr
Operating Benefits 5.35$/hr
Net Cost I0.58$/hr **2.320$/yr
Capital Cost 19.739$/yr
Total Cost 62,059$/yr
C. Special Operation
During the period August 2, 19?l-0ctober 26, 1971, the Regeneration
Plant was operated under special conditions. These conditions were an
0.8 cutib meters/hour feed rate as opposed to a normal rate of 1.2.
45
-------
TABLE H
Capital Expenses For The
Acid Recycle And
Iron Recovery Process
I Development Costs
A) Salaries and Wages
8) Consulting
C) Travel
D) Publications and Reports
Total Development
II
Construction
A) Plans 1)
2)
3)
Recycle Plant
Piping and Pumps
Foundation
B) Sub-contracts
C) Supervision
D) Labor
E) Materials
1)
2)
3)
1)
2)
3)
1)
2)
3)
**)
0
2)
3)
*0
5)
6)
7)
Building
Underground Piping
Ohio Water Service
Air Compression
Recycle Plant
Building
Bui Iding
Piping, Pumps, and Cooling
Erection
Electrical
Cool ing
Recycle Plant
Piping and Pumps
Building
Erection
Foundation
Electrical
Total Construction
Total Capital Expenses
Yearly Capital Cost*
625.00
13,000.00
1,328.00
1.000.00
15,953.00
6,000.00
3,000.00
2.350.00
11,350.00
5,109.00
*t,005.00
10,862.69
88.25
11,000.00
2.037.62
13,125.87
11,578.53
23,509.17
8,627.2**
13.268.90
57,063.8*t
760.00
55,000.00
J7,*+67-*»6
4,293.0*4
1,988.23
1,795.00
2.051.59
83,355.32
175,757.72
191,710.72
19,738.5**
* Based on capital recovery factor of 15 years at 6% (0.10296)
46
-------
TABLE 12 Operating Benefits and Costs For
Normal Operation (Salt Asset)
January 1, 1971 - June 15, 1971
Operating Costs
Units c/Unit £ $/Hr
Production Time, Hours 1,027.75
Main Cooling Water, Ft3 72,792. 0.0948 69.01 0.0672
Aux Cooling Water, Ff> 24,920. 0.6956 173.34 0.1687
220 Power, KWH 4,132. 1.86 76.85 0.0748
440 Power, KWH 294. 1.86 5.47 0.0053
Steam, Lbs 67.689 0.10 67.69 0.0659
Maintenance, Equipment 340.00 0.3308
Labor, Hours 326 1132. 3,690.32 3.59
Operator, Hrs 1,094 1061. 11,607.34 11.29*
Total 16,030.02 15.59
Operating Benefits
Units c/Unit £ $/Hr
Production Time, Hours 1,027.75
Acid Recovery, Lbs P 12% 2,717.384 0.2027 5,508.14 5.36
Salt, Lbs 118,143 0.500 590.72 0.575
Total 6,098.86 5.93
Net Cost 9.66 $/Hr, 38,640 $/Yr*
Total Cost = Capital + oc = 58,379 $/Yr
^Includes company overhead, fringe benefits, s.s., etc.
**8 Hr/shift, 2 shifts/day, 5 days/week, 50 weeks/year
47
-------
TABLE 13 Operating Benefits and Costs For
Normal Operation (Salt Liability)
Operation Costs without salt disposal 15.39 $/hr
Salt disposal 118, \k8 Ibs x 0.300$/lb =
$354.43/1027.75 hr = 0.34 $/hr
Total o.c. 15.93 $/hr
Operating Benefits with salt recovery 5.93 $/hr
Less salt benefits .58 $/hr
Total o.b. 5.35 $/hr
Net cost = 10.58 $/hr, 42,320 $/yr
Total Cost = Capital + oc = 62,059 $/yr
48
-------
The change was initiated in order to produce a drier salt. When the
Mahoning Valley Sanitary District ran a pilot test using 10 tons of
the salt, they found that the coagulation results were excellent; how-
ever, the salt tended to bulk in their hoppers. They hypothesized
that this was due to surface moisture on the salt. Therefore, we felt
that a reduction in feed rate would lessen the salt production and
possibly produce a drier salt. An initial study of acid recycle and
iron recovery storage hopper indicates that in fact a drier salt was
produced.
From the data of Table 11, and unit costs obtained for utilities,
benefits and costs were calculated and are shown in Table 1^. The
results are summarized below.
Special Operation
Operating Cost *»7.37 $/hr
Operating Benefits 3.95 $/hr
Net Cost J»3.ii3 $/hr 173,680 $/yr
Capital Cost 19,739 $/yr
Total Cost 193,^39 $/yr
D. Cost Summary
Analyzing the results of the Normal Operation and the Special
Operation and present consideration of the ferrous sulfate heptahydrate
as a liability we may conclude that the normal conditions are typical
of the plant operation. This results in a yearly total cost of 62,059
$/yr. Production, sales, and waste volumes were obtained from company
data and Table 15 summarizes the results.
E. Resources Utilization
In order to determine the overall acid recycle plant efficiency a re-
sources utilization table was made, Table 16. This table is based on a
5 day working week, 2 shifts/day. During this period of study, the
plant was up 9*»% of the time. Note that the utilization of auxiliary
cooling water and 220 power are 26% and 50% respectively. This is
because there are units such as electric blowers for heaters and water
seals for pumps operating continuously. The plant is now only operating
ku% of the time and could be operated 3 shifts/day and 7 days a week if
necessary.
A similar resource utilization table was made for the Special Operation,
Table 17. The table is based on a 5 day working week, two shifts/day.
During the period of study the plant was up 25% of the time. This low
value was due to the fact that considerable down time occurred awaiting
shipment of replacement parts. Also note that auxiliary cooiling water
utilization did not change from the Normal Operation condition because
it runs continuously.
49
-------
TABLE 1** Operating Benefits and Costs For
Special Operation
August 2, 1971-October 26, 1971
Operating Costs
Production Time, Hours-
Main Cooling Water, Ft-3
AUX Cooling Water, Ft3
220 Power, KWH
440 Power, KWH
Steam, Lbs
Maintenance, Equipment
Labor, Hours
Operator, Hr
Units
244.50
19.899
15,170
1,666
69
17,362
66
992.
C/Unit
0.0948
0.6956
1.86
1.86
0.10
1132.
1061.
J_
18.B6
105.52
30.99
1.2S
17.36
137.
747.12
10,525.12
11,583.25
$/Hr
0.0771
0.4316
0.1267
0.0052
0.0710
0.5603
3.056
43.04
47.37*
Production Time, Hours
Acid, Recovery, Lbs @ 12%
Salt, Lbs
Total
Operating Benefits
244.5
430,974
18,7.37
0.2027
0.500
837.55
93.69
967.24
Net Cost 43.42 $/Hr, 173,680 $/Yr**
Total Cost = Capital + oc = 193,439 $/Yr
**8 Hr/shift, 2 shifts/day, 5 day/week, 50 weeks/yr
*|ncludes company overhead, fringe benefits, s.s., etc,
3.5728
0.3832
3.9560
50
-------
TABLE 15 Cost Summary
Total Yearly Cost 62,059 $/year
1971 Production 35,5^0 tons/year
Cost/Ton Produced 1.75 $/ton production
1971 Sales 10,150,00 $
Cost/$ Sales 0.614 t cost/$ sales
1971 Waste Volume 4,800 M3/year
Cost/M3 Waste 12.93 $/M3
51
-------
TABLE 16 Resources Utilization For
Normal Operation
January 1, 1971-June 15, 1971
Utilization
Time, Hours
Main Cooling Water, Ft3
AUX Cooling Water, Ft3
220 Power, KWH
440 Power, KWH
Steam, Lbs
Waste, M3
Up-Time**
Down-Time***
Units/Hr
1.0
70.44
6.848
1.9911
0.2712
65.8614
1.2
Units
1027.75
72,395
7,038
2,046
279.
67,689
1,233.3
Units
66.25
397.
17,882.
2,086
15
0
79.5
Total
1094.00*
72,792
24,920
4,132
294
67,689
1,312.8
% UP
93.94
99.45
28.24
49.51
94.89
100.00
93.94
*Based on 8 Hr/shift, 2 shifts/day, 119 days
**Actua1 time when acid recycle plant is operating
***ldle, repair, or maintenance time
52
-------
TABLE 17 Resources Utilization For
Special Operation
August 2, 1971-October 26, 1971
Up-Time**
Down-Time***
Time, Hours .
Main Cooling Water, Ft'
AUX Cooling Water, Ft3
220 Power, KWH
440 Power, KWH
Steam, Lbs
Waste M3
Units/Hr
1.000
75.944
12.856
1.879
0.285
71.008
0.8
Units
244.5
18,569
3,143
459
69
17,361
195.6
Units
747.5
1,330
12,027
1,207
0
0
598
Total
992.00*
19,899
15,170
1,666
69
17,362
793.6
% UP
24.64
93.31
20.71
27.55
100.00
100.00
24.64
*Based on 8 hr/shift, 2 shifts/day, 62 days
** Actual time when acid recycle plant is operating
*** Idle, repair, or maintenance time
53
-------
SECTION X
REFERENCES
Chemical Economic Handbook, Stanford Research Institute, Menlo Park,
California, Report 736.5030 A-8, January, 1970.
"Limestone Treatment of Rinse Waters from Hydrochloric Acid Pickling
of Steel," Enviromental Protection Agency, Water Quality Office,
Project 12010 DUL, February, 1971.
Oil, Paint, and Drug Reporter, Chemical Profile Section, U. S.
Department of Commerce, Issue #\kt March 31, 1969.
Oil, Paint, and Drug Reporter, 1967 Census of Manufacturers, SIC-28199,
U. S. Department of Commerce.
"Profitable Pickle Liquor Regeneration" by A.E. Dembitz, Industrial
Wastes, June, I960, pp. 50-52.
"The Cost of Clean Water," Volume Ml, Industrial Waste Profile No. 1
Blast Furnaces and Steel Mills. U. S. Department of the Interior,
Federal Water Pollution Control Administration, September 25, 1967.
"The Solubility of Ferrous Sulfate in Aqueous Solutions of Sulfuric
Acid," by W. Bui lough, T. A. Canning, and M. I. Strawbridge, Journal of
Applied Chemistry, Vol. 12, December, 1952, pp. 703-707.
Treadwell Corporation, 1700 Broadway, New York, N. Y. 10019, personal
correspondence with S. B. Tuwiner, January 10, 1972.
54
-------
SECTION XI
APPENDIX
A. Operating Records
During the period of Normal Operation January 1, 1971-June 15, 1971,
and Special Operation August 2, 1971-October 26, 1971, accurate rec-
ords were kept on the operation of the plant. These records include
date, water consumption, power consumption, temperatures at all
critical locations, feed rates, and iron and acid contents of influent
and regenerated pickle liquor. The reduction of this data is shown in
Table 18. This data includes gregorian date, hours of operation,
cooling water consumed, and power consumed. At the same time records
were kept of the Ferrous Sulfate Heptahydrate produced. The 118,1^3
pounds were produced from January 1, 1971-June 15, 1971, and 18,737
pounds were produced from August 2, 1971-October 26, 1971.
B. Market Survey of Ferrous Sulfate
1. Introduction
The Fitzsimons Steel Co. has installed a Keram Chemie-Lurgi Sulfuric
Acid Regeneration Process at their plant in Youngstown, Ohio. ThPs
installation is Fitzsimons1 response to the need to cease the dumping
of pickle liquor from their plant into the Mahoning River. The re-
generation unit not only recovers sulfuric acid—which can, in turn,
be re-used in the pickling process—but also turns out a by-product
called ferrous sulfate heptahydrate (FeS0^.7H20). Fitzsimons cold-
rolls steel bars, rods and coils from purchased hot-rolled stock.
Annual output of roughly ^0,000 tons results in "production" of approx-
imately 110 tons per month of the ferrous sulfate by-product from the
Keram Chemie process. At the present time, Fitzsimons is paying to
have the material trucked away.
2. Objectives and Procedural Steps
The specific objectives of the study were these: (a) determine the
principal end-use markets for ferrous sulfate; (b) measure the current
size of each principal market—both on a national basis and within the
"local" trading area; (c) determine price structures, distribution
channels, delivery requirements, and packaging considerations; (d)
draw conclusions regarding both the national and local markets—and
make recommendations regarding the appropriate courses of action for
Fitzsimons. Another "unwritten" objective of the work was to try and
locate companies and/or governmental agencies with an interest in
eventual purchase of the material from Fitzsimons. (As previously
stated, Fitzsimons is currently paying to have the ferrous sulfate
trucked away. If they can locate .a firm that will take it "off their
55
-------
TABLE 18
Operating Consumptions of Acid Recycle & Iron Recovery Plant
Date
7.
8.
11.
13.
14.
15.
18.
19.
20.
21.
22.
23.
25.
26.
2?i
28*
29.
33.
3^.
46.
47.
48.
49.
50.
51.
53.
54.
55.
56.
57.
58.
60.
61.
62.
63.
64.
67.
68.
69.
70.
71.
72.
74.
75.
76.
77.
78.
Time
Hour
9.00
11.00
11.00
22.00
9.50
8.00
8.00
7.50
7.50
7.00 •
7.00
11.00
7.00
8.00
7.50
8.50
7.50
7.50
7.50
6.50
8.00
8.00
9.00
7.00
7.50
8.00
7.50
9.00
16.50
5.00
12.00
7.50
5.00
6.00
17.00
7.50
12.00
15.00
6.00
6.00
17.50
13.00
17-00
16,50
16.50
17.00
16.50
Main
Water
Ft**3
0.
66.
1029.
1123.
567.
349.
442.
689.
461.
12.
1146.
1093.
590.
831.
759.
504.
536.
477.
549.
370.
575.
669.
644.
572.
531.
597.
576.
1237.
1259.
1203.
822.
567.
1268.
1271.
1394.
489.
747.
906.
1373.
1445.
1428.
890.
1365.
1137.
1141.
1012.
1156.
Main
Water
Ft**3
0.
0.
100.
220.
80.
70.
70.
90.
60.
60.
70.
101.
70.
70.
60.
80.
60.
70.
60.
70.
70.
70.
70.
60.
60.
160.
50.
70.
100.
100.
90.
40.
110.
110.
120.
40.
1880.
80.
90.
0.
90.
60.
90.
70.
70.
60.
70.
Power
440
KWH
2.
3.
1.
5.
2.
1.
2.
2.
2.
1.
2.
4.
1.
2.
2.
2.
2.
1.
2.
2.
2.
2.
3.
1.
3.
3.
2.
2.
5.
4.
3.
2.
5.
5.
5.
91.
3.
3.
6.
4.
5.
2.
5.
4.
4.
4.
4.
Power
440
KWH
4.
122.
37.
51.
19.
,14.
11.
17.
23.
31.
3.
137.
118.
16.
83.
21.
7.
9.
16.
105.
4.
14.
115.
13.
24.
15.
4.
9.
37.
35.
19.
24.
31.
29.
17.
25.
19.
49.
21.
31.
46.
18.
3-1.
26.
28.
27.
37.
56
-------
TABLE 18 (Con't.)
Date
Time
Hour
Main
Water
Ft**3
Ma in
Water ,
Ft**3
Power
440
KWH
Power
440
KWH
79.
81.
82.
83.
84.
85.
86.
88.
91.
92.
98.
99.
104.
105.
106.
110.
112.
113.
114.
116.
117.
118.
120.
121.
124.
125.
127.
128.
130.
131.
132.
135.
137.
138.
139.
140.
12.00
17.50
17.50
17.50
17,50
17.50
12.00
17,50
17.50
13.50
15.00
12.00
8.00
16.00
5.00
15.00
5.75
15.00
10.50
15.00
15.00
15.00
14.00
10.50
15.00
14.00
39.00
10.50
15.00
14.00
14.50
12.00
15.00
15.00
14.00
15.00
545.
1117.
1226.
1237.
988.
1075.
441.
1176.
891.
750.
686.
452.
344.
678.
211.
1247.
516.
1157.
10823.
1312.
1040.
1242.
993.
648.
567.
640.
883.
510.
982.
653.
745.
707.
767.
894.
690.
677.
20.
70.
60.
50.
50.
70.
70.
90.
40.
60.
150.
40.
20.
30.
40.
50.
30.
130.
70.
150.
120.
110.
130.
20.
100.
70.
100.
150.
110.
90.
828.
70.
110.
120.
130.
120.
2.
4.
5.
4.
3.
4.
3.
4.
4.
3.
5.
3.
2.
4.
1.
5.
2.
3.
3.
4.
4.
4.
4.
2.
4.
4.
4.
f.
4.
4.
4.
4.
4.
3.
3.
3.
23.
37.
19.
29.
35.
18.
18.
27.
20.
21.
57.
27.
12.
127.
121.
125.
25.
35.
18.
15.
26.
124.
34.
18.
39.
19.
24.
16.
14.
0.
121.
20.
118.
19.
18.
21.
57
-------
hands"--hopeful1y for a price, it will considerably improve the eco-
nomics of the installation—in addition to solving the pollution
problem they faced prior to installation of the Keram Chemie process.)
Procedural steps taken during the course of the study were these:
1. Determine the basic objectives of the work.
2. The second step was a visit to see the Keram Chemie process in
operation—and to set up a "sample" program whereby those firms
expressing interest in the ferrous sulfate material could be
furnished quickly with test-size samples.
3. Identification of: a) major producers of ferrous sulfate--and
b) major firms selling the material in the U. S.--through public
sources.
4. These firms were directly contacted in order to determine the
size and segmentation of the national and local markets for
ferrous sulfate.
5. Secondary sources were contacted in order to glean information
regarding markets.
6. Within the "trading area" of Fitzsimons, (roughly a 60 mile radius),
the twelve major cities were contacted regarding their current
practices in water and/or sewage treatment. In addition, major
distributors and other industrial users within the area were also
contacted to determine relative sizes of other markets.
7. A sample and analysis program was set up~and there are currently
nine cities and/or industrial firms actively testing the Fitzsimons1
product.
£. The final step was the drawing of conclusions and the making of
recommendations to deal most effectively with the ferrous sulfate
disposal problem.
A total of approximately 70 field contacts were made during the course
of the study. Opinions regarding markets, etc. tended to steer in
much the same direction from most respondents. This is, of course,
good, since it indicates that a solid "plateau" has been reached—and
that the results of the study are truly indicative of the market
situation as it exists. Fitzsimons was openly identified as the
sponsor of the survey—and a number of unsolicited kind remarks were
made by respondents regarding the efforts of Fitzsimons to deal with
their pollution problems in a business-like manner. Cooperation from
the respondents was excellent with only a very few exceptions.
58
-------
3. National Markets
The following table reflects the production, shipments and dollai
values of the ferrous sulfate "commercially-produced" in the U. S,
during the period 1960-1967.
TABLE 19 - Production, Shipment, and Dollar Value Of Ferrous
Sulfate "Commercially Produced"*
Production
I960
1961
1962
1963
152.2
1965
1966
196?
Estimated
1975
15*4.9
159. &
172.6
183.9
20&.7
196.6
275-300
Shipments
Year (OOP's tons) (OOP's tons)
94
102
100
101
99
120
,3
,5
,8
,9
,4
,7
,3
112.0
150-175
Percent:
Shipments
to Production
63%
64%
66%
63%
58%
55%
57%
57%
Same
Value
(OOP's of $)
$ 955
931
1,004
955
955
983
1,091
1,023
$1,300-$!, 500
-Includes only "commercially-produced" or so-called "merchant" product
As can be seen in the table, commercial production of ferrous sulfate
has grown from an annual level of approximately 150,000 tons annually
in I960—to around 200,000 tons per year in 19&7. (1967 was the most
recent yearly figure available in secondary source material.) A very
important consideration is reflected in the comparison of the "shipments"
column to the "production" column. The percentage of total production
that is actually sold and shipped ranges from 55% up to only 66% of total
during the years shown. This includes interplant transfers
panies produce ferrous sulfate for internal usage
Further, in addition to the 200,000 tons produced commercially each year--
it is estimated by reliable trade sources that an additional 1.2 million
tons of ferrous sulfate is generated as a by-product in steel pickling--
and 1.5 million tons are generated as a by-product in the production of
titanium dioxide. These by-products are generally in slurry or "wet"
form—not nearly the same quality as the commercial grades which are
basically dry as far as sulfate water is concerned. However, the
figures indicate the massive surplus of product available in this market—
with the result that the by-product grades are currently being disposed
where corn-
in other products.
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of by some positive cost method — such as high pressure deep well
injection. On the other hand, the Fitzsimons by-product from the
Chemie process is more in line from a physical standpoint with the
commercial grades currently on the market. This makes the product
much more salable since it is more pure—and doesn't contain the
great amounts of surface water that virtually restrict the shipping
radius to the immediate locale. (It should be noted that the amount
of ferrous sulfate generated as a by-product in the pickling of steel
is decreasing over the years as the major mills switch from the use of
sulfuric acid to hydrochloric acid for pickling. The major reason
for the switch is that much less volume of HC1 is used in pickling--
with the result that there is a substantially lower quantity of material
to dispose of than when sulfuric acid is used.)
a. Producers
There are five commercial producers of ferrous sulfate in the U. S.
The following table reflects their current production plants and their
maximum annual capacities:
TABLE 20 Commercial Producers of Ferrous Sulfate
>,
Producer Capac i ty
Iln tons)
American Cyanamid Co.
Piney River, Va. 25,000
Cosmin Corp.
Baltimore, Md. ^0,000
National Lead Co.
Sayreville, N. J. 100,000
National Lead Co.
St. Louis, Mo. 100,000
i
Pfizer, Inc.
Easton, Pa. 50,000
Pfizer, Inc.
E. St. Louis, Mo. 25,000
Steel Chemical Co.
Lemont, 111. 15.000
TOTAL 355,000
National Lead Co. is the major commercial producer of ferrous sulfate--
currently owning and operating nearly 60% of the industry's total
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capacity; Pfizer is second—followed by Cosmin, American Cyanamid and
Steel Chemical Co.
Another point to notice is that the production capacity of the industry
in commercial-type plants (355,000 tons) is considerably higher than
the current rate of production—which runs approximately 200,000 tons
annually. Again, this point is made to draw emphatic attention to the
fact that the ferrous sulfate industry is suffering from a production
glut—not a shortage of materials.
b. Market Segmentation
Of the current annual commercial output of ferrous sulfate of approxi-
mately 200,000 tons, the percentage of total flowing into the various
"absorbing" industries are these:
TABLE 21
Distribution of Ferrous Sulfate Consumers
Market Segments Percent of Total Tonnage
Iron Oxide Pigments
Ferrites
Water-Sewage Treatment
Others (Fertilizers; stock feed; inks)
Sources: U. S. Department of Commerce; "Oil, Paint and
Drug Reporter"
Iron oxide pigments represent the biggest single commercial market for
ferrous sulfate—currently absorbing approximately 55% of total annual
output. The material is used in the manufacture of paint. (Many of
the major paint firms produce their own titanium dioxide—and utilize
the ferrous sulfate generated in this process rather than buying all
of their needs outside. However, paint producers still represent the
largest single group of purchasers of commercial grades.) Another 30%
of the commercially-produced material is used in the production of
ferrites. Ferrites are used primarily in the manufacture of electronic
hardware—including inductors, transformers, microwave systems, antenna
rods, etc. Ferrous sulfate is converted into ferric oxide from which
the ferrites are then produced.
A big surprise came in the percent of total commercially produced
ferrous sulfate that is being used in water and sewage treatment. , It
was felt when the survey was commenced that this might be the largest
single market—at least from a tonnage absorption standpoint. However,
only 5% of the merchant total is absorbed in these applications. (Large
amounts of the pickling and titanium dioxide by-product are used in
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this application in the "wet" form. However, this is only in areas
where it is readily aval 1 able and has to be shipped only short distances
such as in Chicago, Milwaukee and Detroit.) Looking into the future,
the potential market for ferrous sulfate of commercial grades (which,
for all intents and purposes included the Fitzslmons output) in water and
sewage treatment is expected to grow significantly. Many of the plants
contacted are still in primary treatment stages. Increasing stringency
of pollution laws is forcing these people to consider secondary—and
even tertiary treatment, in many cases. Chemists throughout the industry
informed us that when this happens, the demand for the "dry, pure" prod-
uct (of the type rendered by the Keram Chemie Process) will intensify
greatly since it is considered an excellent product for flocculation in
secondary and "polishing" operations—particularly when used in combin-
ation with synthetic polymers.
The remaining 10% of the commercially-produced ferrous sulfate flows
into a number of diverse uses including: fertilizer (particularly in
areas where increased acidity of soil is required): animal feeds; the
production of inks, dyestuffs, etc. However, all of these applications
require "special" grades that would most probably require "special"
grades that would most probably require some additional processing beyond
the original state in which the Fitzsimons product is recovered (drying,
bagging, etc.).
4. Local Markets
After examining the characteristics of the market from a national stand-
point, it became obvious that the best chance for Fitzsimons to sell their
ferrous sulfate was within a "logical" shipping radius of the plant in
Youngstown, Ohio. First, since Fitzsimons has no interest at all in
becoming involved in a bagging operation, etc. the material must be moved
in some bulk form. Further, Fitzsimons would prefer to steer clear of
any further processing of the material (drying, blending, etc.).. These
factors virtually dictate that the best chances for selling the product
under "where is, as is" conditions exist within a logical bulk shipping
radius of the Fitzsimons plant in Youngstown, Ohio.
In order to determine how far the material could actually be shipped in
bulk before it came into "head-to-head" competition with ferrous sulfate
from other sources—or a substitute material, contacts were made with
many of the major chemical firms presently handling ferrous sulfate
through their distribution setups. In the opinion of these persons, the
logical shipping radius for bulk material of the type produced at
Fitzsimons would be in the 75-100 mile maximum range. However, this
point is not purely definitive. For example, if the Fitzsimons produce
should prove to have a chemical make-up and/or physical characteristics
that happen to fulfill a specific need for a user in a different part
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of the country—It is possible that the particular user would be
willing to bear the cost of shipping the material long distances in
bulk. However, this is considered an unlikely possibility by most
of the "expert" merchandisers in the field.
As a result, a study of the market for ferrous sulfate within a 75
mile radius of Youngstown was conducted in order to try and determine
the most active potential prospects for the Fitzsimons material. The
results of the survey are presented in this section.
a. Market Segments
Each of the major national markets for ferrous sulfate was investigated
within the Youngstown trading area (75 mile radius). A brief synopsis
of the results is reflected in the table on the following page.
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TABLE 22 Current Usage and Relative Market
Potential of Ferrous Sulfate In The
Youngstown, Ohio Trading Area
Major Current Usage of Relative Market
Market Segments Ferrous Sulfate Potential
Pigments All captive * ' Poor
Ferrites None produced in area Poor
Sewage None—better chance Poor—but
in future years improving
Water ,„* None Fair
Others ^ ' Negligible Poor
(1) PPG, Glidden and Sherwin-Williams all either produce their own
needs from titanium dioxide—or buy outside through Eastern firms
on long-standing contractual basis.
(2) Very few firms producing feed, fertilizers within the area. 0. M.
Scott Co. of Marysville, Ohio, uses only ferrous ammonia sulfate--
have gotten away from the use of straight ferrous sulfate.
As shown in the table, the current usage of ferrous, sulfate within the
Youngstown trading area is virtually nil. There are only a few firms
located within the area that produce fertilizers, feeds, etc. None of
these expressed an interest in the material—and none are currently
using ferrous sulfate in their products. This means that the only real
potential for the material lies in the sewage and/or water treatment
systems of the various cities within the shipping radius of 75 miles.
Following is a brief report of the current activities in the 13 major
communities in the area:
Pittsburgh, Pa.
ALCOSAN (Allegheny County Sewer Authority) advised that they are
currently experimenting with an IE gallon per minute test unit working
with spent pickle liquors from the steel mills in the Pittsburgh area.
However, they are quite interested in the Fitzsimons product because of
its dry form and apparent purity. Alcosan chemists admit that they are
under, some pressure to try and help out the Pittsburgh mills by finding
some useful purpose for their spent liquors. However, as they move
into secondary treatment, they are desirous of testing the "pure"
product of Fitzsimons against the impure spent liquors of the local
mills. (Alcosan has been furnished a 100 Ib. sample of the Fitzsimons
product for testing in the near future.) There are a number of water
companies in the Pittsburgh area. American Water Works operates 86
water purification plants in this area. We were informed that many have
waters with a high pH of 9-10 — and that the ferrous sulfate should
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probably be easily oxidized in these systems. They were furnished a
5 lb. sample and intend to run jar tests in late April. Both of these
organizations (Alcosan and American Water Works) have also been furnished
the latest chemical analysis of the Fitzsimons material.
Akron, Ohio
The Sewage Department is presently using only polymers as flocculants
although the entire matter of chemical additives is under study by water
consulting engineers. The same holds true for the Water Department.
The whole matter of considering other materials is over a year away for
Akron. No interest in samples at this time.
Cleveland, Ohio
Cleveland's sewage treatment setup is broken down into three geographic
segments—called westerly, easterly and southern. All follow much the
same practices. Ferrous sulfate does not fit into their plans. They
use alum in great quantities but are trying to get away from this prac-
tice since they feel that any "sulfate" causes problems with their
equipment. They have been approached by Republic and the other steel
firms in the Cleveland area to work with their liquors but have had no
success in their testing programs. The Water Department gives much the
same story--no current usage and no particular interest at this time.
Mansfield, Ohio
Sewage Department is moving into secondary treatment and is currently
using 2-3 carloads per year of anhydrous ferric chloride as a coagulant
for sludge. Has no idea if ferrous sulfate would do a better job—and
would be interested in a sample after they have run the chloride for
about six months. In water purification, Mansfield handles about 3
billion gallons per year. They currently use alum and caustic soda as
chemical additives. They have never tried ferrous sulfate since their
pH is low and they feel that alum Is better under these circumstances.
No interest in test ing^program at this time.
McKeesport, Pa.
We included one of the Pittsburgh suburbs that has an independent water
company. They have experimented with ferrous sulfate through jar tests
only. The stability was good but they are dubious about the resulting
color.
Wheeling, W. Va.
The Wheeling Water plant claimed that they have used ferrous sulfate for
the past 8-9 years as a coagulant with lime. The product that they are
using is "Ferrifloc" purchased from the Opalco Co. in Pittsburgh. They
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process 8 million gallons per day with approximately 8 parts per million
of "Ferrifloc" and use about 90 tons per year—received in 35-*»5 ton
carloads in bulk, ivory in color—and they think it has been successful
because of the high acidity of the water (9.2). We checked out the
Opalco Co. in Pittsburgh (their supplier) and find out that "Ferrifloc"
is actually ferric sulfate rather than ferrous. The two products are
different. We feel that the Wheeling people we talked to misinterpreted
or misunderstood the fact that the Fitzsimons product was ferrous, not
ferric. The Wheeling Sewage Plant uses primary treatment only at this
point. As a result, chlorine is their only additive. They feel that
they will be forced to move into secondary treatment within two years,
and at that time they would be willing to consider ferrous sulfate in a
testing program.
Canton, Ohio
No ferrous sulfate used in either water or sewage treatment facilities.
Sewage is into secondary treatment—• but are considering the possibilities
of going to the Zimpro Process which obviates the need for chemical
additives.
Youngstown, Ohio
The Youngstown Sanitary District handles all of the water purification
for the area. At the present time, they are using alum as a coagulating
agent in their system. The amount of water processed is about 38 million
gallons per day @ 8.5 parts of alum per million—which amount to about
500 tons per year. It is purchased in bulk carloads. The water in the
Youngstown system is a very high pH—in excess of 10—-and it was
suggested that the Fitzsimons product might work well to reduce the pH.
Arrangements have been made for a sizable sample to be furnished.
Cincinnati, Ohio
Cincinnati uses polymers in their sewage treatment—claiming that most
newer plants are being designed for the use of polymers in place of chem-
icals. The next step is to eliminate chemical and synthetic additives
altogether. Cincinnati now has a pilot plant utilizing some type of
thermal treatment that does just that. In water treating, Cincinnati
uses ferric sulfate and alum. They do not use any ferrous iron salts
nor polymers. They have no interest in testing the Fitzsimons product
at the present time.
Columbus, Ohio
In their water treatment system, Columbus currently uses alum and
chlorine—no other chemicals. In sewage, they use a combination of
polymers and ferric chloride. They have tested sulfates for sewage
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treatment but claim that they destroy the nylon filters in their
process. No present interest in treating new additives at present
time.
Warren, Ohio
In water treatment, Warren used to use "iron salts" many years ago.
However, they switched over to alum because it produces less sludge
in their system. They use 200 Ibs. of alum per hour—or 77 tons per
month. It is delivered in 20 ton truck loads from the Cleveland area.
In the treatment of water, Warren used ferric chloride for years. They
have never switched to ferrous sulfate since they do not feel it is as
efficient. However, at the present time, they are using an antionic
polymers which produces much less sludge than did the ferric chlorides.
This relieves the pressure on the sludge filters. One point is this:
ferrous sulfate is excellent for use in sewage treatment when an abund-
ance of phosphate is present. Unless the government cracks down on
detergents, the use of ferrous sulfate and chlori.de may become more
popular in the future.
Sharon, Pa.
Buy water from Shenango Valley Water Co. These people report that they
have tried ferrous sulfate and that it does not work well with Shenango
River water because of the low alkalinity of the river's water. Further,
ferrous sulfate leaves too much turbidity and does not remove iron traces
efficiently. They use alum which they find takes out color and pro-
vides excellent coagulation. Usage amounts to approximately 500 tons
per year.
In sewage disposal, Sharon at one time used about a barrel a day of
ferric chloride and 1ime--but now have arranged to have tank trucks
haul away the sludge from the digesters. They have never used sulfates
and are currently interested in testing same.
Erie, Pa.
At the present time, Erie does not have much of a treatment facility
for sewage. They are in the process of planning new facilities however—
and will be interested in testing the Fitzsimons ferrous sulfate in
about one year because they do have a problem with phosphates. In
water treatment, they have tried ferrous sulfate but it reduced the
water to pH far below their tolerable limits of 7.3-7.5. In addition,
the sulfate resulted in some color transfer or "red water" was it was
termed. As a result, Erie uses alum for coagulation. They feel that
the use of ferrous sulfate would be restricted when lake water is used—
but might prove valuable in highly alkaline water which generally comes
from ground sources.
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In addition to the above cities that lie within the 75 mile trading
radius of Youngstown—Detroit, Chicago and Milwaukee were contacted to
see what might be going on in these areas where steel is produced in
quantity. In Detroit, the water treatment people were using alum at
a dosage rate of 7 parts per million. Both the water and sewage treat-
ment facilities are ferric chloride for phosphate control. The
material is received from Great Lakes Steel Co. and Ford Motor Co.'s
steel facilities in River Rouge. Both use hydrochloric acid pickling--
and currently give the material to the City for the cost of hauling it
away. However, starting S-l-71, the city will pay $1.25 per ton plus
hauling costs—to both parties. They have no source of ferrous sulfate
in Detroit since the mills have gone over to HC1 pickling. As a result,
Detroit wants a sample of the Fitzsimons material—and that has been
sent.
Milwaukee used to use only ferric chloride in both water and sewage treat-
ment. Now they are also using ferrous sulfate since it is delivered
without cost. Phosphate control is the major justification for the
usage.
Chicago uses ferric chloride—plus some ferric sulfate. They have tried
polymers but found them excessively expensive. The sulfates they use
are purchased co-mercially since the spent pickle liquor available from
the local mills is too unpredictable and impure for safe usage.
b. Testing Programs
It is clear from our coverage of the 75 mile trading area that there is
no "unfilled" or unsatisfied demand for ferrous sulfate within the area.
As a matter of fact, the market is glutted—as it is nationally. While
this does not sound good, there is one very important factor that must
be kept in mind. The Fitzsimons product is considered far above the
level of spent pickle liquor in quality and physical characteristics
by those that have seen and tested it. Further, the application of a
chemical additive to a sewage and/or water treatment setup cannot be
proved successful or unsuccessful without testing. As several chemists
pointed out—the application of a chemical additive to a process is much
like the selection of a drug for a patient by a physician. While there
may be six or seven drugs on the market from various pharmaceutical,
houses with the same generic name—the physician must actually experiment
with the drugs to see which one does the job he wants done for his patient,
The same holds true with ferrous sulfate. Since the Fitzsimons product
is considerably different than the spent pickle liquors currently being
tested in many places, the final prospects for disposition of the material
will only be known after tests are run by various interested parties.
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Those of us involved in the survey are convinced that the material can
be sold—and at the very least, disposed of at no cost to Fitzsimons.
There are currently nine companies and/or cities set up to test the
material. Several are very optimistic about their possibilities of
using the material in sizeable quantities. The test situations that
are now under way—and their current status--are as follows:
Mahoning Valley Sanitary District, Youngstown, Ohio
The Chief Chemist has received five pound sample—and more recently,
several tons of material for testing in water treatment. Latest reports
are that the material is testing well, and that there are good possi-
bilities that Mahoning Valley may be able to use a substantial portion
of the monthly Fitzsimons generation of about 110 tons.
Allegheny County Sanitary Authority (ALCOSAN), Pittsburgh, Pa.
A 100 pound sample has been delivered to the Assistant Superintendent
of the plant. They are currently testing spent pickle liquor from the
Pittsburgh area mills and plan to run comparative tests with the
Fitzsimons material late in April.
American Water Works Co., Pittsburgh, Pa.
Delivered a five pound sample of Fitzsimons ferrous sulfate to the
Chief Engineer, at their Mt. Lebanon Boulevard location. They operate
a number of plants that are handling water with a very high pH value
and they feel that the sulfate would oxidize easily and perhaps work
well. Mr. Catlin is the man who will run jar tests on waters from several
of their plants starting in late April when he returns from a leave.
Pittsburgh Water Company, Pittsburgh, Pa.
Received a five pound sample and have run two jar tests. The Chief
Chemist reported that tests were "negative" and that the material would
not be useful in their process.
Hampshire Chemical Division of W. R. Grade Co., Nashua, N. H.
The Vice-President and General Manager requested a one pound sample for
test—plus a chemical analysis. The sample is in his hands but no
report has been received at the time of this writing.
'$"•>"! ••'.' '' -•'• '
Traylor Chemical and Supply Co., Orlando, Florida
Contact made with the General Manager. This company is a very large
distributor of chemicals operating around the entire Southeastern states.
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They expressed much interest in the material for use in fertilizer blends
for the citrus groves where they need added acidity in the soil. A one
pound sample has been sent. No word back as yet.
By-Products Processing Co., Inc., Baltimore, Maryland
A one pound sample has been forwarded to above named company. The initial
report is that they feel they "might" be able to use the entire output.
However, no report on the sample has been forthcoming as yet.
Drew Chemical Co., Boonton, N. J.
i
One pound sample sent to above company for testing. This is a large
basic chemical company and they feel that they may be able to use the
material if it "tests out" properly. No report back at time of writing.
City of Detroit Metro Water District, Detroit, Michigan
A one pound sample sent to the Chief Water Treatment Chemist. Will test
and report back. No word as yet.
5. Other Sales Factors
Some of the miscellaneous factors surrounding the marketing of ferrous
sulfate uncovered during the survey were these:
1. Chemists and technical people at the various chemical companies and
in the city water and sewage treatment departments are the primary
"purchase influencers" with regard to the approval of a particular
chemical for usage within their respective systems. This is where
the original marketing "hurdle" lies. Only after the technical
people have tested and cleared the material, the Purchasing Department
enters the picture and price "negotiations" begin.
2. Packaging requirements vary by market. If the material is to be
sold to chemical companies (particularly to local distributors),
there is a good chance that they will want it to be packed in 50,
75 and 100 pound bags. If selling to a water or sewage treatment
plant, it is much more likely that they will want to handle the
material in bulk form. Pneumatic handling systems for either box
cars or trucks are popular for handling of reasonably dry materials. This
permits "pumping" into overhead bin systems from which the materials can
be gravity-fed into the system or into smaller transporting vehicles.
3. Prices for ferrous sulfate vary considerably based on quality. Com-
mercially-produced grades generally command somewhere between $20 and
$*tO per ton, FOBm carload prices, bagged. On the other side of the
coin, the so-called ferrous sulfate in spent pickle liquor form is a
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drug on the market and is often given away free of charge. A logical
price for the Fitzsimons material is judged to be in the range of $10
per ton by those that have seen and tested the material. However, price
is settled by "negotiations" between buyer and seller. As might be
expected, prices have generally been "soft" in the ferrous sulfate
market over the years due to the extreme excess of supply over demand.
k. Delivery requirements in the chemical industry have slowly changed.
Users are moving more towards a shorter inventory situation and requiring
suppliers to deliver more frequently—thus reducing their inventory costs
at the expense of the supplier.
5. The degree of interest in a "new" supplier of ferrous sulfate is minimal.
However, if the product to be offered is physically superior to those
on the market at the present time there is a good possibility that it
might fit into someone's process. If the product is just another "me-too"
situation, then no interest exists.
As was previously stated, there is more than a passing interest in the
Fitzsimons product. First, potential users feel that is is far beyond the
normal pickling by-product in quality and physical characteristics—and
therefore, has a much stronger commercial appeal than does the output of some
of the Pittsburgh mills, for example. Secondly, a number of potential users
expressed admiration for Fitzsimons with regard to their positive action
to handle their pollution problems in a more "intelligent" way than many other
industrial firms. As a result, the firms and cities contacted seem much more
inclined to seriously try and find a useful application for the Fitzsimons
ferrous sulfate than for the normal spent pickle liquor that so many mills
are trying to dispose of in any manner possible.
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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
W
4, T«K- SULFURIC ACID AND FERROUS SULFATE
RECOVERY FROM
WASTE PICKLE LIQUOR
5.
8.
Aut ior;
Seyler, J.K.; Thornton, W.E.; Householder, M.K.,PhD
The Fitzsimons Steel Company, Youngstown, Ohio
12010 FNM
"12.
Oir'-ni-'-atJon
13. Type of
Environmental Protection Agency report number, EPA-660/2-73-032, January 1974,
16. Abstract
This report describes the investigation of the process variables
of a facility for the treatment of spent sulfuric acid pickle
liquor. The process is based on the vacuum crystalization technique
developed by Keram Chemie-Lurgi of Germany. It recovers ferrous
sulfate heptahydrate as a neraly dry solid by-product and recovers
the unreacted acid for recycle to the pickling tank thus eliminating
the discharge of spent pickle liquor and rinse water.
The full scale facility achieved acid recoveries equivalent to
21.2 tons/day of 12% sulfuric acid for recycle and an average of
115 Ibs/hour of 99.56% FeS04'7H2O by-product. Capital costs were
$191,710 or $19,739/year based on a fifteen year life at 6% interest.
Net operating costs were $42,320/year including a $21,400/year
benefit from acid recovery. (no credit of $2,300/year of ferrous
sulfate heptahydrate was included due to the nationwide excess
production over market absorbing ability) .. The total costs were
$62,059/year, $1.75/ton of steel pickled, 0.614$/$ total sales,
or $12.93/cubic meter of wastes treated.
*waste treatment, *industrial wastes, syllfates, crystallization,
centrifugation
37b.
sulfuric acid, spent pickle liquor, ferrous sulfate heptahydrate,
acid recovery
'c. COWRR 1-ie.td & Group
•
13, A
05D
Send To:
WATER RESOURCES SCIENTIFIC INFORMATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON, D.C. 20240
U.S. GOVERNMENT FfflNHNG OFFICE: 197*- 546-317/286
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