KemPel™ Binder for Iron Ore Pelletization

KemPel™ Binder for Iron Ore Pelletization

KemPel™ Binder for Iron Ore Pelletization
TAILORED ORGANIC BINDERS
FOR LOW GRADE ORES
Industry consolidation and global growth in steel markets present both
opportunities and challenges for iron–ore pellet producers. Quality, consistency
KEY BENEFITS
REDUCED SILICA
CONTENT
and tight control over manufacturing costs are essential to success in today’s
complex, demanding and competitive marketplace. In addition to flocculants,
coagulants and de–frothers for the upstream iron–ore concentration process,
Kemira has developed KemPel™ synthetic organic binders for pelletization.
AN ALTERNATIVE TO BENTONITE
INCREASED POROSITY FOR
ENHANCED REDUCIBILITY
CAN BE USED ALONE OR
WITH OTHER BINDERS
FOR FLEXIBILITY
An important development in the beneficiation of iron–ore is the pelletizing
of concentrates derived from low–grade ores and fines. Globally the quality
of mined iron-ore is decreasing, which can be seen in the increasing levels of
silica in concentrate. The most widely used binder in this process, bentonite,
has been a workhorse for the industry; however, bentonite has several
disadvantages that include, but are not limited to, high levels of silica.
Kemira’s KemPel organic binders for agglomeration of iron–ore can be used
as an alternative to or in conjunction with bentonite in the pelletization
process. Joseph J. Poveromo reported on the benefits of organic binders
over bentonite (1400) noting that organic binders reduce acidic gangue
(silica), which results in increased quality of steel and productivity, as
well as decreased fuel consumption in furnaces. Lower silica levels found
in organic binders increase iron content in the final pellet as the binder
is burned off. A lowering of the silica content in direct reduction grade
pellets (DRI) can significantly reduce the costs of melting these pellets in
electric arc furnaces (EAF). Bentonite assays include over 50% SiO2.
KemPel binders can
be tailored to meet the
strength requirements
for different iron ores by
changing the molecular
mass, charge, and charge
density. Additionally,
various additives can
be used to enhance
the performance and
KemPel organic binders
can be used with or
without other binders
increasing flexibility in the
pelletization process.
KEMPEL SYNTHETIC ORGANIC BINDERS
Green Compressive
Strength [kg]
Dry Compressive
Strength [kg] 105°C
Drop
Number
Magnetite Hematite Magnetite Hematite Magnetite Hematite
Compressive
Strength
300°C [kg]
Compressive
Strength
500°C [kg]
Magnetite
Magnetite
Kemira binder
0.05%
0.9
1.1
2.3
6.0
5.4
8.1
4
10
CMC binder
0.05%
1.2
1.2
1.9
3.1
4.2
2.7
4
10
Bentonite
binder 0.5%
1.1
1.0
2.7
5.9
1.6
1.9
9
26
Pilot–scale testing was performed on 6 kg batches of iron–
ore concentrate. Pellets selected for testing were between
10–12.5 mm. Typical dosages for each binder type were
used for these tests.
The table compares Kemira’s organic binder to bentonite
and a commonly used carboxymethyl cellulose (CMC)
binder for both magnetite and hematite ores using our
state–of–the–art pilot pelletization equipment. Our binder
displays excellent green pellet properties.
The table displays two characteristics of the green pellet,
green strength (wet compressive strength) and drop
number. Strength measurements were conducted with an
electronic crush tester. The drop number was measured
by dropping the green pellet from a height of 0.45 m
to a steel plate and observing the number of cracked
pellets. These are measures of the pellet’s ability to
survive transportation and handling in the process before
induration takes place.
Dry pellets in the bottom of the bed need to have enough
strength to withstand the forces in the balling process
and the weight of the pellet layer moving through the
induration process. Furthermore, the pressure drop
caused by the process gas fans places an extra demand
on dry compression strength. Our organic binders provide
dry compressive strength higher than the 2 kg typically
required.
The table also displays the compressive strength of
pellets that have been heat–treated at 300°C and 500°C.
The values at these temperatures give an indication of
the pellets’ sensitivity to heat in the drying stage. This is
also referred to as the shock temperature test of green
pellets. All pellets tested remained intact. Results are
comparable to those reported for the CMC type of binder.
Results for hematite pellets are not shown since the
compressive strength results of hematite iron–ore at
elevated temperatures are strongly dependent on other
additives, like coal, used in iron–ore mixtures.
FULL RANGE OF PELLET PHYSICAL TESTING AND ORE CHARACTERIZATION
Outotec, a leading technology provider to iron–ore, pelletization and sintering processes, tested our KemPel binder
at their Frankfurt, Germany R&D center. The table below indicates that pelletizing results with pilot–scale pellets
produced using Kemira’s KemPel binder with a hematite iron–ore concentrate resulted in an indurated pellet
compressive strength of 290 kgs, which is equivalent to that shown for bentonite. Indurated pellet results exceed the
industry requirement of 250 kg. Other measured pellet properties also show very good results. Our organic binders can
be optimized to meet all processing needs for additional flexibility.
PELLETIZING RESULTS WITH PILOT-SCALE PELLETS PRODUCED USING KEMPEL ORGANIC BINDERS
Kemira binder
0.05%
Bentonite binder
0.5%
Green Compressive
Strength [kg]
Dry Compressive
Strength [kg] 105°C
Drop
Number
Cold Compressive
Strength [kg]
Hematite
Hematite
Hematite
Hematite
1.3
2.0
5
290
1.7
4.3
7
290
GLOBAL NETWORK, LOCAL EXPERTISE
Our state–of–the–art testing and analytical facility is
equipped to conduct the full range of pellet physical
testing and ore characterization. Co–operation with
industry leaders like Outotec and research centers across
the globe can accelerate the introduction of our products
into your pelletization process.
Our R&D network focuses on developing and
commercializing new innovative technologies and
products to meet the needs of global and local customers.
Kemira’s R&D centers are located in Espoo, Finland;
Atlanta, Georgia in the United States; Shanghai, China and
São Paulo, Brazil. Each R&D center offers expertise that is
in high demand in the local and surrounding markets.
Kemira makes this information available as an accommodation to its customers and it is intended to be solely a guide in customers’ evaluation of the products. You must test our products
to determine if they are suitable for your intended uses and applications, as well as from the health, safety and environmental standpoint. You must also instruct your employees, agents,
contractors, customers or any third party which may be exposed to the products about all applicable precautions. All information and technical assistance is given without warranty or guarantee
and is subject to change without notice. You assume full liability and responsibility for compliance with all information and precautions, and with all laws, statutes, ordinances and regulations
of any governmental authority applicable to the processing, transportation, delivery, unloading, discharge, storage, handling, sale and use of each product. Nothing herein shall be construed as a
recommendation to use any product in conflict with patents covering any material or its use.
KemPel is a registered trademark of Kemira Oyj or its subsidiaries.
Kemira Oyj
Europe, Middle-East and Africa
Porkkalankatu 3
Tel +358 10 8611
P.O. Box 330
FI-00101 Helsinki, Finland North America
www.kemira.com
Tel +770 436 1542
South America
Tel +55 11 2189 4900
Asia-Pacific
Tel +86 21 3367 8333
v. 8.3
Kemira in brief
Kemira is a global, over two billion euro, water chemistry company that is
focused on serving customers in water-intensive industries. The company
offers water quality and quantity management that improves customers’
energy, water, and raw material efficiency. Kemira’s vision is to be a leading
water chemistry company.