American Water Works Association
ANSI/AWWA B406-97
(Revision of ANSI/AWWA B406-92)
R
AWWA STANDARD
FOR
FERRIC SULFATE
Effective date: Feb. 1, 1998.
First edition approved by AWWA Board of Directors Jan. 23, 1961.
This edition approved June 15, 1997.
Approved by American National Standards Institute Dec. 1, 1997.
AMERICAN WATER WORKS ASSOCIATION
6666 West Quincy Avenue, Denver, Colorado 80235
Copyright © 1998 American Water Works Association, All Rights Reserved
AWWA Standard
This document is an American Water Works Association (AWWA) standard. It is not a specification.
AWWA standards describe minimum requirements and do not contain all of the engineering and
administrative information normally contained in specifications. The AWWA standards usually
contain options that must be evaluated by the user of the standard. Until each optional feature is
specified by the user, the product or service is not fully defined. AWWA publication of a standard
does not constitute endorsement of any product or product type, nor does AWWA test, certify, or
approve any product. The use of AWWA standards is entirely voluntary. AWWA standards are
intended to represent a consensus of the water supply industry that the product described will
provide satisfactory service. When AWWA revises or withdraws this standard, an official notice of
action will be placed on the first page of the classified advertising section of Journal AWWA. The
action becomes effective on the first day of the month following the month of Journal AWWA
publication of the official notice.
American National Standard
An American National Standard implies a consensus of those substantially concerned with its scope
and provisions. An American National Standard is intended as a guide to aid the manufacturer, the
consumer, and the general public. The existence of an American National Standard does not in any
respect preclude anyone, whether that person has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the
standard. American National Standards are subject to periodic review, and users are cautioned to
obtain the latest editions. Producers of goods made in conformity with an American National
Standard are encouraged to state on their own responsibility in advertising and promotional
materials or on tags or labels that the goods are produced in conformity with particular American
National Standards.
CAUTION NOTICE: The American National Standards Institute (ANSI) approval date on the front
cover of this standard indicates completion of the ANSI approval process. This American National
Standard may be revised or withdrawn at any time. ANSI procedures require that action be taken
to reaffirm, revise, or withdraw this standard no later than five years from the date of publication.
Purchasers of American National Standards may receive current information on all standards by
calling or writing the American National Standards Institute, 11 W. 42nd St., New York, NY 10036;
(212) 642-4900.
Copyright © 1998 by American Water Works Association
Printed in USA
ii
Copyright © 1998 American Water Works Association, All Rights Reserved
Committee Personnel
The AWWA Subcommittee on Ferric Sulfate–Ferrous Sulfate, which developed
this standard, had the following personnel at the time:
Brannon H. Wilder, Chair
J.E. Brown, Southeast Water Purification Plant, Houston, Texas
N.R. Everill, Fe3 Inc., Celina, Texas
D.E. Gordon, QC Corporation, Baltimore, Md.
M.E. Kenney, Eaglebrook Inc., Schereville, Ind.
C.L. Payne, Synergy Production Inc., Westminster, Md.
F.E. Rowe, Boliden Intertrade Inc., Atlanta, Ga.
B.H. Wilder, Atlanta, Ga.
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The AWWA Standards Committee on Iron Salts, Aluminum Salts, and Related
Coagulant Aids, which reviewed and approved this standard, had the following
personnel at the time of approval:
Thomas M. Vandiver, Chair
Sally J. Smart, Secretary
Consumer Members
B.S. Aptowicz, Philadelphia Water Department, Philadelphia, Pa.
T. A. Barber Jr.,* Coca-Cola USA, Columbus, Ohio
J.A. Bella, Passaic Valley Water Commission, Little Falls, N.J.
J.E. Brown, Southeast Water Purification Plant, Houston, Texas
J.P. Corless Jr., WSSC—Water Operations, Laurel, Md.
E.D. Lowther Jr., American Water Works Service Company, Voorhees, N.J.
R.S. Schultz, Bloomington Water Works, Hudson, Ill.
J.S. Trotter, City of Bloomington Utilities, Bloomington, Ind.
T.M. Vandiver, Coca-Cola USA, Atlanta, Ga.
D.P. Wolz, City of Wyoming Wastewater Treatment Plant, Grandville, Mich.
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General Interest Members
D.T. Duke, East Liverpool, Ohio
J.E. Dyksen,† Council Liaison, United Water New Jersey, Hackensack, N.J.
J.D. Edwards, Burgess & Niple Ltd., Columbus, Ohio
J.J. Gemin, Proctor & Redfern Ltd., Kitchener, Ont.
G.P. Hanna Jr., Fresno, Calif.
R.D. Harriger, Williamsburg, Va.
E.L. Melear, Pitman-Hartenstein & Associates, Jacksonville, Fla.
J.F. Myatt,* Proctor & Redfern Ltd., London, Ont.
* Alternate
† Liaison, nonvoting
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J.W. Patterson, Patterson Associates Inc., Chicago, Ill.
E.S. Ralph,* Standards Engineer Liaison, AWWA, Denver, Colo.
R.R. Smith, Austell, Ga.
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Producer Members
N.R. Everill, Fe3 Inc., Celina, Texas
D.E. Gordon, QC Corporation, Baltimore, Md.
C.B. Lind, General Chemical Corporation, Syracuse, N.Y.
J.J. Pavlicek, PVS Technologies, Detroit, Mich.
F.E. Rowe, Boliden Intertrade Inc., Atlanta, Ga.
K.S. Salmen, Nalco Chemical Company, Naperville, Ill.
S.J. Schneider, Rhone–Poulenc Basic Chemical Company, Shelton, Conn.
S.J. Smart, Alexander Chemical Corporation, LaPorte, Ind.
* Liaison, nonvoting
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Contents
All AWWA standards follow the general format indicated subsequently. Some variations from this format may be
found in a particular standard.
SEC.
PAGE
SEC.
PAGE
Foreword
3
Definitions .......................................... 1
I
I.A
I.B
I.C
II
II.A
4
4.1
4.2
4.3
Requirements
Physical Requirements......................... 2
Chemical Requirements ....................... 2
Impurities.............................................. 2
5
5.1
5.2
5.3
5.4
5.5
5.6
5.9
5.10
Verification
Sampling ...............................................
Laboratory Examination ......................
Laboratory Samples .............................
Moisture Content of Ferric Sulfate .....
Test Procedure for Insoluble Matter...
Test Procedure for Soluble Ferrous
Iron .....................................................
Test Procedure for Soluble Ferric
Iron .....................................................
Test Procedure for Free Acid in
Ferric Sulfate.....................................
Test Procedure for Chloride.................
Basis for Rejection................................
6
6.1
6.2
6.3
Delivery
Marking................................................. 8
Packaging and Shipping ...................... 8
Affidavit of Compliance........................ 9
II.B
II.C
III
III.A
III.B
IV
V
Introduction........................................ vii
Background......................................... vii
History. ............................................... vii
Acceptance. ......................................... vii
Special Issues. ................................... viii
Manufacture and Use of Ferric
Sulfate. ........................................... viii
Storage and Handling
Considerations. .............................. viii
Basis for Payment................................ ix
Use of This Standard........................... ix
Purchaser Options and
Alternatives....................................... ix
Modification to Standard..................... ix
Major Revisions.................................... ix
Comments............................................. ix
5.7
5.8
Standard
1
1.1
1.2
1.3
General
Scope ...................................................... 1
Purpose .................................................. 1
Application............................................. 1
2
References ........................................... 1
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Copyright © 1998 American Water Works Association, All Rights Reserved
3
4
4
4
4
5
6
7
7
8
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Copyright © 1998 American Water Works Association, All Rights Reserved
Foreword
This foreword is for information only and is not a part of AWWA B406.
I. Introduction.
I.A. Background. Ferric sulfate is used as an inorganic coagulant for removal
of suspended and colloidal particles from water by coagulation and flocculation. It is
prepared by oxidizing ferrous sulfate or by dissolving ferric oxide in sulfuric acid.
Ferric sulfate is available in dry form as a powdery-granular product, grayish-white
to reddish-gray in color, or as a stable solution that is relatively clear and reddishbrown in color. The term ferric sulfate as used in this standard refers to the
manufactured ferric sulfate product, a partially hydrated dry ferric sulfate having
the basic formula Fe2(SO4)3 · xH2O in which x averages approximately 4.5. This ferric
sulfate dissolves rapidly in water, as contrasted with anhydrous ferric sulfate, which
dissolves very slowly in water. Similarly, in this standard the term liquid ferric
sulfate refers to a solution of ferric sulfate containing about 50 percent, by weight, of
the dry form ferric sulfate as defined in this standard. This percentage may be varied
by agreement between the supplier and purchaser.
I.B. History. This standard was first approved as tentative on Jan. 23, 1961, by
the AWWA Board of Directors and was approved as a standard on Feb. 11, 1964.
Subsequent revisions to ANSI/AWWA B406 were prepared by the AWWA Standards
Committee on Iron Salts, Aluminum Salts, and Related Coagulant Aids in 1987 and
1992. This edition was approved by the AWWA Board of Directors on June 15, 1997.
I.C. Acceptance. In May 1985, the US Environmental Protection Agency
(USEPA) entered into a cooperative agreement with a consortium led by NSF
International (NSF) to develop voluntary third-party consensus standards and a
certification program for all direct and indirect drinking water additives. Other
members of the original consortium included the American Water Works Association
Research Foundation (AWWARF) and the Conference of State Health and Environmental Managers (COSHEM). The American Water Works Association (AWWA) and
the Association of State Drinking Water Administrators (ASDWA) joined later.
In the United States, authority to regulate products for use in, or in contact with,
drinking water rests with individual states.* Local agencies may choose to impose
requirements more stringent than those required by the state. To evaluate the health
effects of products and drinking water additives from such products, state and local
agencies may use various references, including two standards developed under the
direction of NSF, ANSI†/NSF‡ 60, Drinking Water Treatment Chemicals—Health
Effects, and ANSI/NSF 61, Drinking Water System Components—Health Effects.
Various certification organizations may be involved in certifying products in
accordance with ANSI/NSF 60 (61). Individual states or local agencies have authority
to accept or accredit certification organizations within their jurisdiction. Accreditation of certification organizations may vary from jurisdiction to jurisdiction.
*Persons in Canada, Mexico, and non-North American countries should contact the
appropriate authority having jurisdiction.
†American National Standards Institute, 11 W. 42nd St., New York, NY 10036.
‡NSF International, 3475 Plymouth Rd., Ann Arbor, MI 48106.
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Copyright © 1998 American Water Works Association, All Rights Reserved
Appendix A, “Toxicology Review and Evaluation Procedures,” to ANSI/NSF 60
(61) does not stipulate a maximum allowable level (MAL) of a contaminant for
substances not regulated by a USEPA final maximum contaminant level (MCL). The
MALs of an unspecified list of “unregulated contaminants” are based on toxicity
testing guidelines (noncarcinogens) and risk characterization methodology (carcinogens). Use of Appendix A procedures may not always be identical, depending on the
certifier.
AWWA B406-97 addresses additives requirements in Sec. 4.3 of the standard.
The transfer of contaminants from chemicals to processed water or the residual solids
is becoming a problem of greater concern. The language in Sec. 4.3.2 is a
recommendation only for direct additives used in the treatment of potable water to be
certified by an accredited certification organization in accordance with ANSI/NSF
Standard 60, Drinking Water Treatment Chemicals—Health Effects. However, users
of the standard may opt to make this certification a requirement for the product.
Users of this standard should also consult the appropriate state or local agency
having jurisdiction in order to
1. Determine additives requirements, including applicable standards.
2. Determine the status of certifications by all parties offering to certify
products for contact with, or treatment of, drinking water.
3. Determine current information on product certification.
II. Special Issues.
II.A. Manufacture and Use of Ferric Sulfate. Due to the corrosivity of chlorides on some metals, this edition of AWWA B406 includes a limitation on chloride
impurity of 10 ppm Cl per each 1 percent of contained ferric iron. This limitation is
based on a static-test corrosion test using a 50 percent liquid ferric sulfate containing
up to 1,000 ppm Cl held at 100°F (38°C), in which no corrosion of 304 or 316 stainless
steel resulted during 21 days of contact. Mild steel as a control, however, was
consumed in several days, regardless of the presence or absence of chlorides. Because
a hot ferric sulfate solution containing chlorides may increase corrosivity or
extraction of metal impurities when loaded, stored, or used at product temperatures
exceeding 100°F (38°C), the purchaser may wish to discuss with the supplier the level
of chlorides, temperatures, and potential corrosivity, particularly with temperatures
exceeding 100°F (38°C).
II.B. Storage and Handling Considerations. Ferric sulfate is mildly hygroscopic and should, therefore, be stored in a dry place. When feeding ferric sulfate, the
correct water ratio (quantity of water to weight of material in the dissolving tank)
should be maintained. The feeding equipment manufacturer’s directions for feeding
should be followed.
Liquid ferric sulfate should be stored in corrosion-resistant tanks and metered
into the water as required with appropriate metering equipment. While liquid ferric
sulfate remains a stable liquid for at least 72 h at –0.4°F (–18°C) without freezing or
crystallizing, with only a slight increase in viscosity, it is recommended that tanks be
insulated or heated if prolonged periods of temperature below 32°F (0°C) are
normally expected.
Human exposure to either dry or liquid ferric sulfate should be minimized by
adequate ventilation, protective clothing, good hygiene, and careful “housekeeping”
practices. Personnel handling dry ferric sulfate should wear goggles, a dust mask,
gloves, and other protective clothing. Those handling liquid ferric sulfate should wear
goggles, gloves, and an acid-resistant apron. Splashing or misting the liquid should
viii
Copyright © 1998 American Water Works Association, All Rights Reserved
be avoided. A respirator with an activated carbon filter suitable for a weak sulfuric
acid mist should be worn when handling liquid ferric sulfate.
II.C. Basis for Payment. The basis for payment shall be the net weight of ferric
sulfate supplied, excluding the weight of the shipping container.
III. Use of This Standard. AWWA has no responsibility for the suitability
and compatibility of the provisions of this standard to any intended application by
any user. Accordingly, each user of this standard is responsible for determining that
the standard’s provisions are suitable for and compatible with that user’s intended
application.
III.A. Purchaser Options and Alternatives. When purchasing ferric sulfate
under the provisions of this standard, the following items should be covered in the
purchaser’s specifications:
1. Standard used—that is, ANSI/AWWA B406, Standard for Ferric Sulfate, of
latest revision.
2. Type of ferric sulfate to be supplied.
3. An affidavit of compliance, certified analysis, or both, if required (Sec. 6.3).
4. If requesting impurity information, the purchaser must state maximum
impurity content limits and the analytical methods to be used to determine
compliance with the limits (Sec. 4.3).
5. Quantity of ferric sulfate required and method of packaging and shipping
(Sec. 5 and 6).
6. Whether weight certificates are required (Sec. 6.2.5).
7. Whether the recommended compliance with ANSI/NSF Standard 60,
Drinking Water Treatment Chemicals—Health Effects, is to be required. If this
certification is to be required, the purchaser’s specifications shall read, “This material
shall be certified as suitable for contact with or treatment of drinking water by an
accredited certification organization in accordance with ANSI/NSF Standard 60,
Drinking Water Treatment Chemicals—Health Effects.”
8. If an analysis by a referee laboratory is required, the assignment of testing
costs should be addressed (Sec. 5.10.1).
III.B. Modification to Standard. Any modification to the provisions, definitions, or terminology in this standard must be provided in the purchaser’s
specifications.
IV. Major Revisions. Major revisions made to the standard in this edition
include the following:
1. The format has been changed to AWWA standard style.
2. The acceptance statement (Sec. I.C) has been revised to approved wording.
3. Item numbers 7 and 8 have been added to Sec. III.A, Purchaser Options and
Alternatives.
4. Section 4.3.2, Product certifications, has been added.
5. Section 1.5.2, Removal of material, has been deleted.
V. Comments. If you have any comments or questions about this standard,
please call the AWWA Standards and Materials Development Department,
(303) 794-7711 ext. 6283, FAX (303) 795-1440, or write to the department at 6666 W.
Quincy Ave., Denver, CO 80235.
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Copyright © 1998 American Water Works Association, All Rights Reserved
American Water Works Association
R
ANSI/AWWA B406-97
(Revision of ANSI/AWWA B406-92)
AWWA STANDARD FOR
FERRIC SULFATE
SECTION 1:
Sec. 1.1
GENERAL
Scope
This standard covers ferric sulfate in dry form and liquid ferric sulfate for use
in water treatment.
Sec. 1.2
Purpose
The purpose of this standard is to provide purchasers, manufacturers, and
suppliers with the minimum requirements for ferric sulfate, including physical,
chemical, packaging, shipping, and testing requirements.
Sec. 1.3
Application
This standard can be referenced in specifications for purchasing and receiving
ferric sulfate and can be used as a guide for testing the physical and chemical
properties of ferric sulfate samples. The stipulations of this standard apply when this
document has been referenced and then only to ferric sulfate used in water supply
service.
SECTION 2:
REFERENCES
This standard has no applicable information for this section.
SECTION 3:
DEFINITIONS
The following definitions shall apply in this standard:
1. Ferric sulfate: A powdery-to-granular ferric sulfate in dry form having the
basic formula of Fe2(SO4)3 · xH2O, in which x averages approximately 4.5, containing
approximately 20.0 percent water-soluble ferric iron.
1
Copyright © 1998 American Water Works Association, All Rights Reserved
2 AWWA B406-97
2. Liquid ferric sulfate: A solution generally containing approximately
50 percent, by weight, of the dry-form ferric sulfate as defined in this standard.
3. Manufacturer: The party that manufactures, fabricates, or produces
materials or products.
4. Purchaser: The person, company, or organization that purchases any
materials or work to be performed.
5. Supplier: The party that supplies material or services. A supplier may or
may not be the manufacturer.
SECTION 4:
Sec. 4.1
REQUIREMENTS
Physical Requirements
4.1.1 Ferric sulfate. Ferric sulfate supplied in the dry form under the
requirements of this standard shall be fairly uniform in size. Not less than 95 percent
shall pass a No. 4 US Standard Sieve, and 100 percent shall pass a No. 3 sieve. The
material shall be free from lumps or extraneous materials. It shall be free-flowing
and suitable for storage, without caking, in closed hopper bins and for feeding by dryfeed machines.
4.1.2 Liquid ferric sulfate. Liquid ferric sulfate shall be free from extraneous
materials and shall be transported and delivered at such concentration and
temperature that no freezing occurs. The liquid shall be suitable for feeding by means
of metering pumps and other metering devices constructed of corrosion-resistant
materials.
Sec. 4.2
Chemical Requirements
4.2.1 Ferric iron. Ferric sulfate shall contain not less than 18.0 percent
water-soluble ferric iron (Fe3+), and liquid ferric sulfate shall contain not less than
9.0 percent water-soluble ferric iron (Fe3+), except by agreement between the supplier
and purchaser.
4.2.2 Ferrous iron. Water-soluble ferrous iron (Fe 2+) shall not exceed
3.0 percent in ferric sulfate; it shall not exceed 1.5 percent on a basis of 9.0 percent
ferric iron in liquid ferric sulfate.
4.2.3 Water-insoluble matter. Not more than 6.5 percent of the ferric sulfate
shall be insoluble in water and not more than 0.1 percent shall be insoluble in liquid
ferric sulfate.
4.2.4 Free acid. Ferric sulfate shall contain free acid, but it shall not exceed
4.5 percent as H2SO4. Liquid ferric sulfate shall contain sufficient acid as H2SO4 so
solution pH is 2 or less to ensure product stability.
4.2.5 Chlorides. Not more than 10 ppm chloride shall be present per each
1 percent of ferric iron content at 100°F (38°C).
Sec. 4.3
Impurities
4.3.1 General impurities. Ferric sulfate conforming to this standard shall
contain no substances in quantities capable of producing deleterious or injurious
effects on the health of those consuming water that has been properly treated with
ferric sulfate.
4.3.2 Product certifications. Ferric sulfate is a direct additive used in the
treatment of potable water. This material should be certified as suitable for contact
Copyright © 1998 American Water Works Association, All Rights Reserved
FERRIC SULFATE
3
with or treatment of drinking water by an accredited certification organization in
accordance with ANSI*/NSF† Standard 60, Drinking Water Treatment Chemicals—
Health Effects. Evaluation shall be accomplished in accordance with requirements
that are no less restrictive than those listed in ANSI/NSF Standard 60. Certification
shall be accomplished by a certification organization accredited by the American
National Standards Institute.
SECTION 5:
Sec. 5.1
VERIFICATION
Sampling
5.1.1 Sampling point. Samples shall be taken at the point of destination.
5.1.2 Ferric sulfate.
5.1.2.1 If ferric sulfate is handled by conveyor or elevator, a mechanical
arrangement for sampling may be used.
5.1.2.2 If the material is packaged, 5 percent of the packages shall be sampled,
but no fewer than 5 packages and no more than 15 packages shall be sampled from
any one shipment. No sample shall be taken from a broken package.
5.1.2.3 Ferric sulfate shall be sampled using a sampling tube that is at least
3⁄4
in. (19 mm) in diameter.
5.1.2.4 The total gross sample, which shall weigh at least 10 lb (5 kg), shall be
mixed thoroughly and divided to provide three 1-lb (0.45-kg) samples. The samples
shall be sealed in airtight, glass containers. Each sample container shall be labeled
to identify it, and the label shall be signed by the sampler.
5.1.3 Liquid ferric sulfate.
5.1.3.1 Equal portions shall be taken at five equally spaced intervals during
the unloading of a tank truck or railroad car. Where small quantities are purchased
in small containers, at least 5 percent of the containers shall be sampled, but not less
than 5 and no more than 15 containers shall be sampled from any one shipment. The
total gross sample shall be at least 2 qt (1.9 L).
5.1.3.2 The total gross sample shall be thoroughly mixed, and three 1-pt (0.5-L)
containers filled and retained. Containers shall be polyethylene plastic containers or
glass containers having a plastic corrosion-resistant cap. Each sample container shall
be labeled to identify it, and the label shall be signed by the sampler.
5.1.4 Distribution of samples. One of the three sealed samples is for immediate use by the purchaser for testing of the shipment in accordance with Sec. 5. The
two remaining samples shall be retained for future use in accordance with Sec. 5.10,
if necessary.
5.1.5 Sample retention. Samples shall be retained for at least 30 days after
the date of receipt of the shipment before they are discarded.
*American National Standards Institute, 11 W. 42nd St., New York, NY 10036.
†NSF International, 3475 Plymouth Rd., Ann Arbor, MI 48106.
Copyright © 1998 American Water Works Association, All Rights Reserved
4 AWWA B406-97
Sec. 5.2
Laboratory Examination
5.2.1 Completion of testing. The purchaser’s laboratory examination of one of
the three samples collected in accordance with Sec. 5.1 shall be completed within
10 working days after receipt of the shipment.
5.2.2 Test procedures. Methods of testing ferric sulfate shall conform to the
procedures set forth in this standard. Alternative procedures may be used only with
the written approval of the purchaser.
Sec. 5.3
Laboratory Samples
5.3.1 Sample preparation and sieve analysis for ferric sulfate. Riffle or quarter the sample to provide two samples: one sample of 150–200 g for physical screen
size determination, and a second sample of approximately 100 g for the chemical
analyses. After thorough mixing, store the quartered 100-g sample in an airtight
glass container and weigh it out rapidly to avoid a change in moisture content. Grind
approximately 50 g of the 100-g sample to such a size that all of it passes through a
No. 80 US Standard Sieve. Place this ground sample in a tightly closed bottle or jar
until analysis.
Quantitatively transfer the 150–200 g sample to an 8-in. diameter US Standard
set of sieves composed of a No. 3 sieve, a No. 4 sieve, and a pan. Sieve by lateral and
vertical motion accompanied by a jarring action. Continue for about 5 min or until an
additional 3 min of sieving time fails to change the results of any sieve fraction by
0.5 percent of the total sample weight.
5.3.2 Sample preparation for liquid ferric sulfate. Weigh 20 g (±0.001 g) of the
sample collected in accordance with Sec. 5.1.3 and transfer it into a 100-mL
volumetric flask. Dilute to the volume mark with deionized water and mix.
Sec. 5.4
Moisture Content of Ferric Sulfate
5.4.1 Procedure. Weigh 10 g (±0.001 g) of the ground sample in a preweighed
porcelain dish. Dry for 5 h in an oven at 230°F (110°C). Allow the sample to cool in a
desiccator and then weigh it again.
5.4.2 Calculation.
loss in weight, in grams × 100
percent moisture = ---------------------------------------------------------------------------------weight of sample, in grams
Sec. 5.5
Test Procedure for Insoluble Matter
5.5.1 Procedure for insoluble matter in dry ferric sulfate. Weigh 10 g (±0.001 g)
of the ground sample (Sec. 5.3.1) and transfer it into a 250-mL beaker. Add 100 mL
of boiling water and stir for 30 min. Do not allow the mixture to boil. Filter the
contents of the beaker using a Fisher Filtrator, or equivalent, with Whatman No. 42
filter paper, or equivalent, into a 400-mL filter flask, and wash the residue with four
successive 20-mL portions of boiling water poured into the same flask. Transfer the
contents of the filter flask quantitatively to a 500-mL volumetric flask. Add distilled
water to 400 mL, cool to room temperature, make to volume, and mix. Save this
filtrate for other analyses. Ignite the filter paper and residue in a preweighed
platinum crucible in a muffle furnace. Cool in a desiccator and weigh (to 0.001 g)
again. Report results as percent insoluble matter on an oven-dry basis, using the
percent moisture from Sec. 5.4 and the formula in Sec. 5.5.1.1.
Copyright © 1998 American Water Works Association, All Rights Reserved
FERRIC SULFATE
5.5.1.1
5
Calculation for ferric sulfate:
weight of residue, in grams × 100
percent water-insoluble matter = ------------------------------------------------------------------------------------------100 – percent moisture
10.0 g * × --------------------------------------------------------------100
*Sec. 5.3.2.
5.5.2 Procedure for insoluble matter in liquid ferric sulfate. After thoroughly
shaking the 100-mL sample prepared in Sec. 5.3.2, filter it using a Fisher Filtrator,
or equivalent, equipped with preweighed Whatman No. 42 filter paper, or equivalent.
Remove the filtrate and save it for further analyses, then thoroughly wash the
residue on the filter with distilled water. Discard this wash water. Dry the filter
paper with residue to constant weight; cool and reweigh (accurate to 0.001 g).
5.5.2.1 Calculation for liquid ferric sulfate:
weight of residue, in grams × 100
percent water-insoluble matter by weight = ------------------------------------------------------------------------------------------weight of sample, * in grams
*Sec. 5.3.2.
Sec. 5.6
Test Procedure for Soluble Ferrous Iron
5.6.1 Reagents.
5.6.1.1 0.01N ceric sulfate. To prepare, add slowly while stirring 30 mL of
concentrated sulfuric acid (H2SO4) to 500 mL of water; dissolve 5.28 g of ceric sulfate
[Ce(HSO4)4] in this acid solution and dilute to 1 L (standardized with electrolyticgrade iron wire, arsenic oxide, or sodium oxalate).
5.6.1.2 Orthophenanthroline indicator solution. To prepare, dissolve 0.5 g of
orthophenanthroline in 50 mL of ethyl alcohol and dilute to 100 mL.
5.6.1.3 1:1 hydrochloric acid. To prepare, carefully add equal parts of concentrated hydrochloric acid to distilled water.
5.6.2 Procedure for dry ferric sulfate. To a 10-mL aliquot of the filtrate from
Sec. 5.5.1 plus 80 mL of distilled water, add 5 mL of hydrochloric acid. Titrate with
0.01N ceric sulfate, using orthophenanthroline indicator (use a 10-mL microburette).
Run a blank on 50 mL of water using the same amount of indicator solution. Report
results as percent water-soluble ferrous iron on an oven-dry basis, using the percent
moisture from Sec. 5.4 and the formula in Sec. 5.6.2.1.
5.6.2.1 Calculation for dry ferric sulfate:
percent water-soluble ferrous iron ( Fe
2+
) =
( mL ceric sulfate – blank ) × ( N ceric sulfate ) × 0.05585 × 50 × 100
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 – percent moisture
weight of sample, * in grams × --------------------------------------------------------------100
*Sec. 5.5.1.
5.6.3 Procedure for liquid ferric sulfate. To a 10-mL aliquot of the solution
in Sec. 5.3.2, add 80 mL of distilled water and 5 mL of hydrochloric acid. Titrate with
0.01N ceric sulfate, using orthophenanthroline indicator (use a 10-mL microburette).
Run a blank on 50 mL of water using the same amount of indicator solution. Report
Copyright © 1998 American Water Works Association, All Rights Reserved
6 AWWA B406-97
results as percent water-soluble ferrous iron in the solution using the formula in
Sec. 5.6.3.1.
5.6.3.1 Calculation for liquid ferric sulfate:
percent water-soluble ferrous iron ( Fe
2+
) =
( mL ceric sulfate – blank ) × ( N ceric sulfate ) × 0.05585 × 10 × 100
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------weight of sample, * in grams
*Sec. 5.3.2.
Sec. 5.7
Test Procedure for Soluble Ferric Iron
5.7.1 Reagents.
5.7.1.1 Concentrated hydrochloric acid.
5.7.1.2 Potassium iodide crystals, reagent grade.
5.7.1.3 0.1N sodium thiosulfate (standardized).
5.7.1.4 Starch solution (0.5 g in 100 mL of distilled water).
5.7.2 Procedure for dry ferric sulfate. To a 50-mL aliquot of the filtrate from
Sec. 5.5.1, add 12 mL of concentrated hydrochloric acid in an iodine flask. Add 2–3 g
of potassium iodide crystals. Seal the glass stopper with water and allow it to stand
for 5 min in the dark. Titrate with 0.1N sodium thiosulfate, using fresh starch as an
indicator near the end point. Report results as percent water-soluble ferric iron on an
oven-dry basis, using the percent moisture from Sec. 5.4 and the formula in
Sec. 5.7.2.1.
5.7.2.1 Calculation for ferric sulfate:
percent water-soluble ferric iron ( Fe
3+
) =
( mL thiosulfate ) × ( N thiosulfate ) × 0.05585 × 10 × 100
-----------------------------------------------------------------------------------------------------------------------------------------------------100 – percent moisture
weight of sample, * in grams × --------------------------------------------------------------100
*Sec. 5.5.1.
5.7.3 Procedure for liquid ferric sulfate. To a 50-mL aliquot of solution from
Sec. 5.3.2, add 12 mL of concentrated hydrochloric acid in an iodine flask. Add 2–3 g
of potassium iodide crystals. Seal the glass stopper with water and allow to stand for
5 min in the dark. Titrate with 0.1N sodium thiosulfate, using fresh starch as an
indicator near the end point. Report results as percent water-soluble ferric iron in
liquid ferric sulfate using the formula in Sec. 5.7.3.1.
5.7.3.1 Calculation for liquid ferric sulfate:
percent water-soluble ferric iron ( Fe
3+
) =
( mL thiosulfate ) × ( N thiosulfate ) × 0.05585 × 2 × 100
-------------------------------------------------------------------------------------------------------------------------------------------------weight of sample, * in grams
*Sec. 5.3.2.
Copyright © 1998 American Water Works Association, All Rights Reserved
FERRIC SULFATE
Sec. 5.8
7
Test Procedure for Free Acid in Ferric Sulfate
5.8.1 Reagents.
5.8.1.1 Potassium fluoride solution. To prepare, dissolve 140 g of potassium
fluoride in 800 mL of distilled water and neutralize to phenolphthalein end point
using sodium hydroxide.
5.8.1.2 Phenolphthalein indicator. To prepare, add 5 g of phenolphthalein to
1 L of 50-percent alcohol diluted with boiled distilled water, and neutralize with
sodium hydroxide.
5.8.1.3 0.05N sodium hydroxide (standardized).
5.8.2 Procedure. Transfer 20 mL of the filtrate described in Sec. 5.5.1 (equal
to 0.4 g of sample) to a 150-mL beaker. Add 60 mL of potassium fluoride solution and
titrate immediately with constant mixing, with 0.05N sodium hydroxide to phenolphthalein pink (use a 10-mL microburette). To compensate for the acidity of the
potassium fluoride solution, run a blank, replacing the ferric sulfate solution with
water. Report results as percent free acid on an oven-dry basis, using the percent
moisture from Sec. 5.4 and the formula in Sec. 5.8.2.1.
5.8.2.1 Calculation.
percent free acid ( as H 2 SO4 ) =
( mL NaOH – blank ) × ( N NaOH ) × 0.098 × 25 × 100
-------------------------------------------------------------------------------------------------------------------------------------------------100 – percent moisture
weight of sample, * in grams × --------------------------------------------------------------100
*Sec. 5.5.1.
Sec. 5.9
Test Procedure for Chloride
5.9.1 Reagents.
5.9.1.1 Concentrated HNO3.
5.9.1.2 0.1N of AgNO3 solution.
5.9.2 Procedure for ferric sulfate. Weigh 5 g (±0.001 g) of the ground sample
(Sec. 5.3.1) and transfer to a 250-mL beaker. Add 100 mL of boiling deionized water
and stir for 30 min. Do not allow the mixture to boil. Filter the contents of the beaker
using a Fisher Filtrator, or equivalent, with Whatman No. 42 filter paper, or
equivalent, into a 250-mL beaker, and wash the residue with four successive 20-mL
portions of boiling water poured into the same beaker. Discard the residue. Add 5 mL
of 0.1N AgNO3 to the filtrate. Stir and let set for 30 min. Filter through a tared
crucible and place in the oven at 105°C and dry to constant weight in 11⁄2 to 2 h. Cool
and reweigh the crucible. Subtract from tared weight to obtain the dry residue.
5.9.2.1 Calculation for ferric sulfate and liquid ferric sulfate:
Cl
–1
ppm per each 1 percent Fe
3+
dry residue (g) × 0.2474 × 1,000,000
iron = -------------------------------------------------------------------------------------------------3+
percent Fe
sample weight (g) × ----------------------------------100
5.9.3 Procedure for liquid ferric sulfate. Weigh 10 g of sample (±0.001 g) into
a 250-mL beaker. Add 100 mL of deionized water. Add 1 mL concentrated HNO3. Add
5 mL of 0.1N AgNO3. Stir the solution and let it set for about 30 min. Filter through
a tared crucible. Place the crucible in the oven at 105°C and dry to constant weight
Copyright © 1998 American Water Works Association, All Rights Reserved
8 AWWA B406-97
in 11⁄2 to 2 h. Cool and reweigh the crucible. Subtract from tared weight to obtain the
dry residue. Calculate Cl–1 ppm using the formula in Sec. 5.9.2.1.
Sec. 5.10
Basis for Rejection
5.10.1 Notice of nonconformance. If the ferric sulfate delivered to the purchaser does not meet the requirements of this standard, the purchaser shall provide
a notice of nonconformance to the supplier within 10 days after receipt of the
shipment at the point of destination. The results of the purchaser’s tests shall prevail
unless the supplier notifies the purchaser within five working days after receipt of
the notice of nonconformance that a retest is desired. On receipt of the request for a
retest, the purchaser shall forward to the supplier one of the sealed samples taken in
accordance with Sec. 5.1 of this standard. In the event that the test results obtained
by the supplier on retesting do not agree with the test results obtained by the
purchaser, the remaining sealed sample shall be forwarded, unopened, for analysis to
a referee laboratory agreed on by both parties. The results of the referee analysis
shall be accepted as final.
SECTION 6:
Sec. 6.1
DELIVERY
Marking
6.1.1 Required. Each shipment of packaged or containerized material shall
carry with it some means of identification. Each package, drum, or other container
shall be marked legibly with the name of the product, brand name (if any), the name
of the manufacturer, net weight, and other markings as required by applicable laws
and regulations. When ferric sulfate is shipped in bulk, the same type of information
shall be provided in accordance with applicable regulations.
6.1.2 Optional. Each package, drum, or other container of material may also
bear the statement: “This material meets the requirements of ANSI/AWWA B406,
Standard for Ferric Sulfate,” provided that the requirements of this standard are met
and the material is not of a different quality based on separate agreement between
the supplier and purchaser.
Sec. 6.2
Packaging and Shipping
Packaging and shipping of ferric sulfate shall conform to current federal, state,
and local regulations.
6.2.1 Ferric sulfate. Ferric sulfate shall be shipped in one of the following
ways, as specified by the purchaser: (1) in bulk trucks or freight cars, (2) in 50-lb
(23-kg) or 100-lb (45-kg) moistureproof multiwall paper bags, or (3) in moistureproof
fiber drums each containing approximately 350 lb (160 kg) net.
6.2.2 Liquid ferric sulfate. Liquid ferric sulfate shall be shipped in railroad
tank cars or tank trucks. The tanks shall be rubber-lined or made of stainless steel or
any other suitable material that will not be corroded by the acidity of the liquid. Tank
trucks or tank cars shall be in suitable condition for hauling liquid ferric sulfate and
shall not contain any substances that might affect the use or usefulness of the liquid
ferric sulfate in treating water. If smaller quantities are purchased, the container size
and type shall be determined by agreement between the purchaser and supplier.
Copyright © 1998 American Water Works Association, All Rights Reserved
FERRIC SULFATE
9
6.2.3 Inspection. All bulk carriers or refillable drums shall be carefully
inspected to ensure they are free from contaminating material prior to loading of the
ferric sulfate.
6.2.4 Net weight. The net weight of packages or containers shall not deviate
from the recorded weight by more than 1.5 percent. If a dispute arises concerning the
weight of packaged or containerized material, acceptance or rejection shall be based
on the weight of not less than 10 percent of the packages or containers received,
selected at random from the shipment.
6.2.5 Weight certificates. The purchaser may require that all bulk shipments
of ferric sulfate be accompanied by weight certificates provided by certified weighers;
or the weights may be checked by the purchaser at delivery.
Sec. 6.3
Affidavit of Compliance
The purchaser may require the manufacturer or supplier to furnish either an
affidavit attesting that the ferric sulfate furnished under the purchaser’s specifications complies with all applicable requirements of this standard, or a certified
analysis of the ferric sulfate, or both.
Copyright © 1998 American Water Works Association, All Rights Reserved
1P-7.5M-42406-2/98-MG
Printed on recycled paper.
Copyright © 1998 American Water Works Association, All Rights Reserved