DESCRIPTION
REDUCED-IRON PRODUCTION METHOD AND PRODUCTION DEVICE
Technical Field
The present invention relates to a method and
apparatus for producing reduced iron. More particularly,
the present invention relates to a method and apparatus
for producing high reduced rate iron from iron ore
abundant in phosphorous, zinc and alkali element
impurities, with the concomitant recovery of phosphorous,
zinc and alkali elements.
Background Art
In blast furnaces, convertors or electric furnaces,
reduced iron is used as a material for making molten iron
or molten steel.
Reduced iron is produced from reduction of an
oxidized iron source, such as iron ore or oxidized iron by
a carbonaceous reducing agent (hereinafter referred to as
"carbonaceous material") or a reducing gas. This process,
called direct reduction, is most commonly used to produce
reduced iron.
For producing direct reduced iron (DRI), a rotary
hearth furnace (RHF) is utilized in which pellets composed

of extremely trace iron ore are reduced.
With regard to processes of producing reduced iron
using RHF, for example, reference may be made to Korean
Patent Application Examined Publication No. 10-2010-
0043095 titled "Process for producing reduced iron
pellets, and process for producing pig iron"(Patent
Document 1), and Korean Patent Application Unexamined
Publication No. 10-2010-0122946, titled "Process for
production of direct-reduced iron" (Patent Document 2).
Both Patent Documents 1 and 2 are directed to the
production of reduced iron using a rotary furnace. In
Patent Document 1, particle sizes of raw materials are
controlled to improve reactivity, thereby producing a
reduced iron pellet in which a metallization ratio is
increased while Patent Document 2 discloses the production
of iron ore rich in zinc.
Because conventional rotary furnaces are compactly
configured to reduce iron ore at up to 1,350°C in. a
reducing atmosphere, it is difficult to maintain the
reducing atmosphere within such furnaces. In addition,
conventional rotary furnaces are not suitable for use in
mass scale production due to their annual capacity of
production amounting only to 150,000 ~ 500,000 tons.
Due to the limitations of rotary furnaces, a new
process is required for the mass production of reduced

iron.
In an effort to overcome the limitations of
conventional rotary furnaces,' production of partially
reduced iron under an oxidative atmosphere in a furnace
has been suggested. However, the reducing agent carbon is
burnt with oxygen from the oxidative atmosphere within the
furnace to generate the heat of combustion. That is,
since a larger amount of carbon is used as an energy
source than as a reducing agent for iron ore, the
reduction efficiency of iron ore is poor.
Further, even though iron ore is reduced in a furnace
with an oxidative atmosphere, the reduced iron may be re-
oxidized by the oxidative atmosphere, which is also a
cause of poor reduction rate.
Meanwhile, phosphorus (P) , zinc (Zn) and alkali
oxides (K2O+Na2O) within iron ore are impurities that may
cause various defects in the final reduced iron product.
Iron ore that has a lower content of phosphorus (P) , zinc
(Zn), and alkali oxides (K2O+Na2O) is preferred.
With the gradual depletion of iron ore having a low
impurity content, the cost of quality iron ore has
recently increased. Together with the high material cost,
the depletion makes it more difficult to produce quality
iron ore. In this context, suggestion has been made of a
steel making technique characterized by removing the

impurities. However, this technique requires various
subsidiary materials necessary for the removal of such
impurities, and an additional process of removing
impurities, thus increasing the production cost.
[Related Art Document]
[Patent Document]
(Patent document 1) Korean Patent Application
Unexamined Publication No. 10-2010-0043095 (2010. 04. 27)
(Patent document 2) Korean Patent Application
Unexamined Publication No. 10-2010-0122946 (2010. 11. 23)
Disclosure
Technical Problem
The present invention provides a method for and an
apparatus of producing reduced iron under an oxidative
atmosphere in an open-type furnace.
In the method, and the apparatus, a mixture of iron
ore and carbonaceous material is molded into ore
agglomerates and sufficiently reduced under an oxidative
atmosphere in a reducing furnace.
In addition, the present invention provides a method
and apparatus for producing reduced iron by which a broad
spectrum of iron ores including iron ores rich in one or
more of phosphorus (P), Sine (Zn), or alkali oxide

(K2O+Na2O can be used to effectively produce reduced iron.
Also, the present invention provides a method and
apparatus for producing reduced iron by which phosphorus
(P) , zinc (Zn) and alkali oxides (K2O+Na2O) can be
separated and recovered from the iron ores.
Technical Solution
In accordance with an aspect thereof, the present
invention provides a method for producing reduced iron,
comprising: mixing an iron material bearing phosphorus,
zinc and alkali oxides with a carbonaceous material to
prepare a mixture; forming the mixture into ore
agglomerates; reducing the ore agglomerates in an open-
type reducing furnace, with concomitant removal of
phosphorus, zinc and alkali elements from the ore
agglomerates; crushing the reduced ore agglomerates to
separate reduced iron from phosphorus-bearing slag; and
agglomerating the reduced iron while recovering the slag.
In the mixing step, the mixture contains phosphorus
(P) in an amount of 0.06 % by weight or greater, zinc (Zn)
in an amount of 0.02 % by weight or greater, and an alkali
oxide (K2O+Na2O) in an amount of 0.1 % by weight or
greater.
In one embodiment of the method, the iron material is
selected from among an iron ore having a phosphorus (P)

content of 0.06 % or greater, an iron ore having a zinc
(Zn) content of 0.02 % or greater, an iron ore having an
alkali oxide (K2O+Na2O) content of 0.1 % or greater, and a
combination thereof.
In the mixing step, the carbonaceous material
contains carbon-bearing dust generated from a coal mining
site or a steelworks or both.
In the mixing step, the mixture has a basicity
(CaO/SiO2) of 1 or greater.
In the mixing step, the mixture has an alkali oxide
content of 0.5 % or greater.
In the mixing step, the mixture is further
supplemented with a subsidiary material for adjusting
basicity and an alkali oxide content, said subsidiary
material including CaO to adjust the basicity of the
mixture, and Na2CO3 and K2CO3 to adjust the alkali oxide
content of the mixture.
In another embodiment of the present invention, the
carbonaceous material is used in an amount of 10 parts by
weight or greater, based on 100 parts by weight of the
mixture.
In another embodiment of the present invention, the
reducing furnace maintains an oxidative atmosphere therein
during the reducing step in which gas is generated upon
the reduction of the carbonaceous material within the ore

agglomerates, forming a gas film that surrounds the ore
agglomerates and thus blocks the ore agglomerates from the
oxidative atmosphere.
In another embodiment of the present invention, the
open-type reducing furnace is heated to a temperature of
1,000°C or higher to calcine the ore agglomerates, and
operated for a limited period of time at maximum such that
carbon is completely depleted of the ore agglomerates.
In another embodiment of the present invention, the
reducing step comprises recovering the zinc within the ore
agglomerates as a dust in an exhaust gas from the open-
type furnace, water granulating the recovered dust to
separate zinc oxide (ZnO), and recovering the zinc oxide.
In another embodiment of the present invention,
wherein the zinc within the ore agglomerates is vaporized
during the reduction step in the reducing furnace,
discharged together with the exhaust gas, and reacted with
oxygen of the exhaust gas to form zinc oxide (ZnO) , said
zinc oxide being recovered as a dust.
In another embodiment of the present invention, the
recovered dust is water granulated during which the alkali
element is separated and recovered together with the
water.
In another embodiment of the present invention, the
reduced iron is separated from the slag using a magnetic

seperator.
In accordance with another aspect thereof, the
present invention provides a method for producing reduced
iron, comprising: mixing an iron material with a
carbonaceous material to form ore agglomerates, and
reducing the ore agglomerates in an open-type furnace.
In one embodiment of this method, the carbonaceous
material is used in an amount of 10 parts by weight or
greater, based on 100 parts by weight of the ore
agglomerates, and wherein the reducing furnace maintains
an oxidative atmosphere therein during the reducing step
in which gas is generated upon the reduction of the
carbonaceous material within the ore agglomerates, thus
forming a gas film that surrounds the ore agglomerates and
blocks the ore agglomerates from the oxidative atmosphere.
In accordance with a further aspect thereof, the
present invention provides am apparatus of producing
reduced iron, comprising: a plurality of raw material
hoppers for respectively storing different types of iron
ores therein; a carbonaceous material hopper for storing a
carbonaceous material therein; a mixer for mixing the
effluent of different types of iron ores from the raw
material hoppers with the carbonaceous material from the
carbonaceous material hopper; a first molding press for
forming the mixture into ore agglomerates; an open-type

reducing furnace for reducing the ore agglomerates in an
oxidative atmosphere; a spaller for crushing the ore
agglomerates reduced in the reducing furnace; a magnetic
separator for separating the crushed, reduced particles
into reduced iron and slag by magnetism; and a second
molding press for molding the reduced iron
In one embodiment, the apparatus may further
comprise: a collector for collecting dust from an exhaust
gas from the reducing furnace; and a water granulator for
granulating the collected dust with water to separate zinc
oxide from alkali element-bearing waste water.
Advantageous Effects
As described above, iron ores avoided for use in
conventional iron making processes due to their high
impurity content can be employed for producing reduced
iron on a mass scale under an oxidative atmosphere using
an open-type furnace in accordance with the present
invention.
For a detailed description, the method of the present
invention is provided for producing reduced iron,
comprising: mixing an iron material with a carbonaceous
material to form ore agglomerates; and reducing the ore
agglomerates in an open-type furnace, wherein the reducing
furnace maintains an oxidative atmosphere therein during

the reducing step in which gas is generated upon the
reduction of the carbonaceous material within the ore
agglomerates, thus forming a gas film that surrounds the
ore agglomerates and blocks the ore agglomerates from the
oxidative atmosphere.
Further, impurities such as phosphorus (P) , zinc
(Zn) , and alkali oxides (K2O+Na2O) contained in iron ores
can be utilized in the reducing step, and can be recovered
from the iron.
Consequently, a. broad spectrum of iron ores can be
utilized, which leads to a decrease in the cost of raw
materials used in making iron. In addition, phosphorus
(P) , zinc (Zn) and alkali oxides (K2O+Na2O) can be
recovered the process.
Description of Drawings
FIG. 1 is a schematic view illustrating an apparatus
of and a method for producing reduced iron.
FIG. 2 is a graph illustrating phosphorus recovery
rates in slag versus basicity after the reduction of ore
agglomerates at 1,200°C for 20 min.
FIG. 3 is a graph illustrating phosphorus recovery
rates of slag versus alkali oxide content in ore
agglomerates after the reduction of ore agglomerates
having a basicity of 1 at 1200°C for 20 min.

FIG. 4 is a graph showing the metallization ratio of
ore agglomerates versus the temperature of the open-type
reducing furnace according to the amount of the
carbonaceous material.
Best Mode
Embodiments of the present invention are described
with reference to the accompanying drawings in order to
describe the present invention in detail so that those
having ordinary knowledge in the technical field to which
the present invention pertains can easily practice the
present invention. It should be noted that same reference
numerals are used to designate the same or similar
elements throughout the drawings. In the following
description of the present invention, detailed
descriptions of known functions and configurations which
are deemed to make the gist of the present invention
obscure will be omitted.
First, a description will be given of an apparatus by
which a method for producing reduced iron can be embodied
in accordance with an embodiment of the present ivnention.
With reference to FIG. 1, there is a schematic view
illustrating an apparatus and method for producing reduced
iron.

As can be seen FIG. 1, the apparatus of producing
reduced iron in accordance with one embodiment of the
present invention comprises a first spaller 11 for
crushing iron ore; a plurality of hoppers 21, 22 and 23
for storing the iron ore crushed in the first spaller 11
by type therein; a second spaller 12 for crushing a
carbonaceous material, such as. coal; a carbonaceous
material hopper 30 for storing the carbonaceous material
crushed by the second spaller 12 therein; a mixer 50 for
mixing effluent from different types of iron ore from the
raw material hoppers 21, 22 and 23 with the crushed
carbonaceous material from the carbonaceous material
hopper 30; a first molding press 61 for forming the
mixture into ore agglomerates; an open-type reducing
furnace 70 for reducing the ore agglomerates in an
oxidative atmosphere; a third spaller 13 for crushing the
ore agglomerates reduced in the reducing furnace 70; a
magnetic separator 80 for separating the crushed, reduced
particles into reduced iron and slag by magnetism; and a
second molding press 62 for molding the reduced iron.
Optionally, the apparatus may further comprise at least
one subsidiary material hopper 40 for storing a subsidiary
material therein; a collector 90 for collecting dust from
an exhaust gas from the reducing furnace; and a water

granulator 100 for granulating the collected dust with
water to separate zinc oxide from alkali element-bearing
waste water.
The open-type reducing furnace has an internal space
that is open rather than closed. So long as it can heat
ore agglomerates while continuously transporting the ore
agglomerates, any reducing furnace, without limitations to
specific configurations, may be employed. By way of
example, an open-type reducing furnace may be provided
with a transport means for transporting ore agglomerates
in a conveyer manner. A furnace body defining an internal
space in which the ore agglomerates are conveyed and
reduced is located above the transport means. The
internal space of the furnace body is heated by a
plurality of burners installed therein. In addition, a
suction means for aspirating air from the internal space
of the furnace body is provided below the transport means.
In this structure, ore agglomerates are conveyed by the
transport means while heat flows downwardly from an upper
space of the ore agglomerates by the combustion of the
burners and the aspiration of the suction means. In such
. an open-type furnace, ore agglomerates can be arranged in
a multi-layer pattern and can be continuously reduced to
produce reduced iron on a mass scale.

Each of the first molding press 61 and the second
molding press 62 is a twin role structure.
Next, the production of reduced iron using the
apparatus illustrated above will be described.
Various iron ores are crushed in the first spaller 11
shown in FIG. 1 and individually stored in the iron raw
hoppers 21, 22 and 23 by type. The iron ores may have a
phosphorus (P) content of 0.06 % or greater, a zinc (Zn)
content of 0.02 % or greater, an alkali oxide (K2O+Na2O)
content of 0.1 % or greater, or a combination thereof.
Separately, a carbonaceous material is crushed in the
second spaller 12 and stored in the carbonaceous material
hopper 30.. The carbonaceous material may contain carbon-
bearing dust generated from a coal mining site or a
steelworks or both. In this regard, the carbonaceous
material preferably has a particle size of 0.1 mm or less
so as to enhance reactivity.
In addition, the subsidiary material hopper 40 stores
a subsidiary material for adjusting basicity and a
subsidiary material for adjusting the content of alkali
oxides, in combination or separately, therein. For
instance, CaO may be used as a subsidiary material for
adjusting basicity, and the content of alkali oxides may
be adjusted with Na2CO3 or K2CO3or both.

After being prepared like this, the iron ore, the
carbonaceous material, and the subsidiary materials are
each weighed, introduced into the mixer 50, and mixed to
give a mixture.
Preferably, the mixture comprises phosphorus (P) in
an amount of 0.06 % or greater, zinc (Zn) in an amount of
0.02 % or greater, and an alkali oxide (K2O+Na2O) in an
amount of 0.1 % or greater, which are mostly derived from
the iron ore and the carbonaceous material. However, the
ore agglomerates, as will be described later, are
preferably maintained to have a high basicity and a high
alkali oxide content in order to sufficiently isolate
phosphorus during the reduction of ore agglomerates.
Accordingly, CaO, Na2CO3, and K2CO3 are preferably added in
such amounts as to adjust the basisicity (CaO/SiO2) of the
mixture to 1 or higher and to maintain an alkali oxide
content of 0.5 % in the mixture. The reason why the
basicity and the alkali oxide content are limited will be
revealed later in the description given in conjunction
with FIGS. 2 and 3.
The mixture thus obtained is fed to the first molding
press 61 where homogeneously sized ore agglomerates are
formed.
Subsequently, the ore agglomerates are introduced
into the open-type reducing furnace 7 0 where iron (Fe) of

the ore agglomerates is reduced in an oxidative atmosphere
while separating phosphorus, zinc and alkali elements from
the iron. In this context, the oxidative atmosphere means
exposure to air without any atmospheric control.
Reactions in the reduction process will be detailed.
Iron oxides within the ore agglomerates react (are
reduced), as shown in the following Chemical Formula 1, to
generate Fe and CO. Then, this CO reacts with (reduces)
the iron oxides of the ore agglomerates as shown in the
following Chemical Formula 2, with the concomitant
generation of iron (Fe) and CO2. This CO2 may be converted
into CO by reaction with carbon within the ore
agglomerates. The CO and CO2 gases that are generated by
reactions between iron oxides and carbon within the ore
agglomerates are exhausted externally, forming a gas film
surrounding the ore agglomerates. As the gas film serves
to block the ore agglomerates from the oxidative
atmosphere of the open-type reducing furnace 70, the
reduction of the ore agglomerates can be facilitated in
the open-type reducing furnace 70.
In a preferred embodiment, a sufficient amount of the
gas film is formed by fully reacting iron oxides of the
ore agglomerates with carbon. For this, a sufficient
amount of carbon is contained in the ore agglomerates. In

this regard, the carbonaceous material is preferably mixed
in an amount of 10 parts by weight or greater, based on
100 parts by weight of the total mixture.
In addition, the open-type reducing furnace 70 is
preferably maintained to have a calcination temperature of
1,000°C or higher to reduce the ore agglomerates.
FIG. 4 is a graph showing the metallization ratio of
ore agglomerates versus the temperature of the open-type
reducing furnace according to the amount of the
carbonaceous material. As can be seen, ore agglomerates
containing a carbonaceous material in an amount of 10
parts by weight were found to allow sufficient
metallization.
Since the gas film is formed as a result of a
reaction with the carbon of the ore agglomerates, the time
of the reduction of the ore agglomerates is preferably
limited at maximum to an extent that carbon is completely
depleted of the ore agglomerates.
During the reduction of the ore agglomerates in the
open-type furnace 70, phosphorus, oxygen and CaO elements
of the ore agglomerates undergo a reaction to form a slag
containing the elements in the form of, for example,
CaO (P20s). Hence, the ore agglomerates are in the mixture
of reduced iron and slag.
Turning to zinc contained in the ore agglomerates,

zinc oxide and alkali oxides (K2O+Na2O) are reduced at
lower temperatures than are iron oxides, and are
discharged as an exhaust gas.
When discharged together with the exhaust gas, the
zinc (Zn) vaporized during the reduction of the ore
agglomerates reacts with oxygen in the exhaust gas to form
a zinc oxide (ZnO) that is then collected as a dust by the
collector 90.
During the reduction of the ore agglomerates, the
alkali elements are also vaporized, exhausted as a gas,
and reacted with oxygen of the exhaust gas to form an
alkali oxide. Likewise, this oxide is collected as a dust
by the collector 90.
After the dust collected by the collector 90 is
treated in the water granulator 100, waste water
containing crude zinc oxide and alkali elements is
recovered.
Meanwhile, the ore agglomerates in mixture with
reduced iron and slag are crushed in the third spaller 13
and separated into reduced iron and slag by magnetism in
the magnetic separator 80. The reduced iron thus obtained
is formed into briquettes of a predetermined size in the
second molding press 62 while the slag rich in CaO and
phosphorus may be recycled as a fertilizer material.

EXAMPLES
A better understanding of the present invention may
be obtained through the following examples that are set
forth to illustrate, but are not to be construed as
limiting the present invention.
Compositions of iron ores used in experiments are
summarized in Table 1, below.
Iron ores rich in phosphorus, zinc and alkali
elements (Na2O, K2O) were used. Each iron ore was formed
into briquettes rich in phosphorus, zinc and alkali
elements. Optionally, zinc oxide, phosphorus oxide and
alkali oxides, all in a reagent grade, were added to
maximize contents of zinc, phosphorus and alkali elements.
For comparison, the composition of an iron ore that
is used in a typical iron making process (iron ore C) is
also given in Table 1. As can be in Table 1, iron ore C,
which is used in a typical iron making process, has a
phosphorus content of about 0.06% or less, a zinc content.
of about 0.02 % or less, and an alkali oxide content of
0.03 % or less whereas both iron ores A and B are
relatively rich in phosphorus, zinc, and alkali oxide.



Iron ores A and B were independently mixed with coal
(20 % by weight) and formed into briquettes. In order to
increase basicity and alkali oxide content in the
briquettes, CaO, K2O, and Na2O in a reagent grade were
added. Under a reducing furnace simulated condition, the
briquettes were reduced.
A reduction experiment was carried out on the
briquettes by elevating the temperature at a rate of
50°C/min to a reduction temperature of 1,200°C and by
maintaining the reduction temperature for 20 min. Then,
the briquettes were analyzed for Fe, Zn, and P content
while Fe, Zn, P, K, and Na content in the slag is
examined.
FIG. 2 is a graph illustrating phosphorus recovery
rates in slag versus basicity after the reduction of ore
agglomerates at 1,200°C for 20 min, and FIG. 3 is a graph

illustrating phosphorus recovery rates of slag versus
alkali oxide content in ore agglomerates after the
reduction of ore agglomerates having a basicity of 1 at
1200°C for 20 min.
As is understood from data of FIG. 2, the phosphorous
recovery rate in slag gradually increases with an increase
in basicity. As for the phosphorus oxide (P2O5) , its
stability is maintained in the condition of high basicity.
Particularly, phosphorus oxide in the slag is stable even
when a strong alkali such as alkali oxide is added.
Therefore, the addition of small amounts of highly basic
slag and alkali oxide is effective in preventing
phosphorus oxide from being reduced and dissolved into the
metal Fe during the reduction, of reduced iron, and thus in.
allowing phosphorus oxide to exist in the slag.
After completion of the experiment, the briquettes
were found to have a reduction rate of approximately 85 ~
90% irrespective of basicity. In addition, the zinc
content in the slag after reduction was decreased to
approximately 0.004 % from 0.1 % in the initial phase.
Reduction of zinc oxide to metal Zn occurred at a lower
temperature than reduction of iron oxide to its metal.
Soon after reduction into metal zinc, it was vaporized,
exhibiting a high vapor pressure. The gaseous zinc was

re-oxidized into and discharged as ZnO in exhaust gas.
As can be seen in FIG. 3, the recovery rate of
phosphorous in slag . was observed to increase with an
increase in the alkali oxide content of the briquettes.
Hence, the use of alkali oxide-rich iron ore in mixture
with phosphorus-rich iron ore is advantageous in enhancing
phosphorus recovery rates in slag. Accordingly, it was
found that phosphorus could be recovered to a desired
degree when the mixture was set to have a basicity
(CaO/SiO2) of 1 or higher, and an alkali oxide content of
0.5 % or higher.
Although the preferred embodiments of the present
invention have been disclosed for illustrative purposes,
those skilled in the art will appreciate that various
modifications, additions and substitutions are possible,
without departing from the scope and spirit of the
invention as disclosed in the accompanying claims.

11, 12, 13: Spaller,
21, 22, 23: raw material hopper
30: carbonaceous material hopper
40: subsidiary material hopper

50: mixer
61, 62: molding press
70: open-type reducing furnace
80: magnetic separator
90: collector
100: water granulator

CLAIMS
1. A method for producing reduced iron, comprising:
mixing an iron material bearing phosphorus, zinc and
alkali oxides with a carbonaceous material to prepare a
mixture;
forming the mixture into ore agglomerates;
reducing the ore agglomerates in an open-type
reducing furnace, with concomitant removal of phosphorus,
zinc and alkali elements from the ore agglomerates;
crushing the reduced ore agglomerates to separate
reduced iron from phosphorus-bearing slag; and
agglomerating the reduced iron while recovering the
slag.
2. The method of claim 1, wherein the mixture
contains phosphorus (P) in an amount of 0.06 % by weight
or greater, zinc (Zn) in an amount of 0.02 % by weight or
greater, and an alkali oxide (K2O+Na2O) in an amount of 0.1
% by weight or greater.
3. The method of claim 2, wherein the iron material
is selected from among an iron ore having a phosphorus (P)
content of 0.06 % or greater, an iron ore having a zinc
(Zn) content of 0.02 % or greater, an iron ore having an

alkali oxide (K2O+Na2O) content of 0.1 % or greater, and a
combination thereof.
4. The method of claim 1, wherein the carbonaceous
material contains carbon-bearing dust generated from a
coal mining site or a steelworks or both.
5. The method of claim 1, wherein the mixture has a
basicity (CaO/Si62) of 1 or greater.

6. The method of claim 1, wherein the mixture has an
alkali oxide content of 0.5 % or greater.
7. The method of claim 5 or 6, wherein the mixture is
further supplemented with a subsidiary material for
adjusting basicity and an alkali oxide content, said
subsidiary material including CaO to adjust the basicity
of the mixture, and Na2CO3 and K2CO3 to adjust the alkali
oxide content of the mixture.
8. The method of claim 1, wherein the carbonaceous
material is used in an amount of 10 parts by weight or
greater, based on 100 parts by weight of the mixture.
9. The method of claim 1, wherein the reducing

furnace maintains an oxidative atmosphere therein during
the reducing step in which gas is generated upon the
reduction of the carbonaceous material within the ore
agglomerates, forming a gas film that surrounds the ore
agglomerates and thus blocks the ore agglomerates from the
oxidative atmosphere.
10. The method of claim 9, wherein the open-type
reducing furnace is heated to a temperature of 1,000°C or
higher to calcine the ore agglomerates and operated for a
period of time limited at maximum to an extent that carbon
is completed depleted of the ore agglomerates.
11. The method of claim 1, wherein the reducing step
comprises recovering the zinc within the ore agglomerates
as a dust in an exhaust gas from the open-type furnace and
water granulating the recovered dust to separate zinc
oxide (ZnO), and recovering the zinc oxide.
12. The method of claim 11, wherein the zinc within
the ore agglomerates is vaporized during the reduction
step in the reducing furnace, discharged together with the
exhaust gas, and reacted with oxygen of the exhaust gas to
form zinc oxide (ZnO), said zinc oxide being recovered as
a dust.

13. The method of claim 11, wherein the recovered
dust is water granulated during which the alkali element
is separated and recovered together with water.
14. The method of claim 1, wherein the reduced iron
is separated from the slag using a magnetic separator.
15. A method for producing reduced iron, comprising:
mixing an iron material with a carbonaceous material
to form ore agglomerates, and
reducing the ore agglomerates in an open-type
furnace.
16. The method of claim 15, wherein the carbonaceous
material is used in an amount of 10 parts by weight or
greater, based on 100 parts by weight of the ore
agglomerates, and wherein the reducing furnace maintains
an oxidative atmosphere therein during the reducing step
in which gas is generated upon the reduction of the
carbonaceous material within the ore agglomerates, thus
forming a gas film that surrounds the ore agglomerates and
blocks the ore agglomerates from the oxidative atmosphere.
17. An apparatus of producing reduced iron,

comprising:
a plurality of raw material hoppers for respectively
storing different types of iron ores, therein;
a carbonaceous material hopper for storing a
carbonaceous material therein;
a mixer for mixing effluent from different types of
iron ores from the raw material hoppers with the
carbonaceous material from the carbonaceous material
hopper;
a first molding press for forming the mixture into
ore agglomerates;
an open-type reducing furnace for reducing the ore
agglomerates in an oxidative atmosphere;
a spaller for crushing the ore agglomerates reduced
in the reducing furnace;
a magnetic separator for magnetically separating the
crushed and reduced particles into reduced iron and slag;
and
a second molding press for molding the reduced iron
18. The apparatus of claim 17, further comprising:
a collector for collecting dust from an exhaust gas
from the reducing furnace; and
a water granulator for granulating the collected dust
with water to separate zinc oxide from alkali element-

bearing waste water.