TITLE OF THE INVENTION
METHOD AND DEVICE FOR MANUFACTURING COAL BRIQUETTES
CROSS-STANDARD TO RELATED APPLICATION
This application claims priority to and the benefit of Korean Paten5 t
Application No. 10-2014-0187661 filed in the Korean Intellectual Property Office
on December 23, 2015, the entire contents of which are incorporated herein by
reference.
10 BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a method and a device for
manufacturing coal briquettes, and particularly, to a method and a device for
manufacturing coal briquettes used in a heat source and a reducing agent in a
15 smelting reduction iron making method. More particularly, the present
invention relates to a method and a device for manufacturing coal briquettes
capable of manufacturing coal briquettes with high manufacturing efficiency by
directly molding powdered coal briquettes generated in a process of
manufacturing coal briquettes used in a melter gasifier during a smelting
20 reduction iron making process.
(b) Description of the Related Art
In general, a method for manufacturing molten iron by directly using coal
for general use, which is difficult to use as a fuel, and a reducing agent in a
furnace method, and directly using iron ore as an iron source is referred to as a
2
smelting reduction iron making method. As the smelting reduction iron making
method, a FINEX process using a fluidized reduction furnace and a melter
gasifier connected thereto is a representative commercialized process. Coal
briquettes used in the melter gasifier are subjected to a storage process after
being manufactured. In this case, since the coal briquettes are subjected 5 to
drop impact in a chute between belts during transferring and subjected to
compression load in a storage bin, sufficient cold working quality should be
secured.
In order to secure cold working quality as described above, coking coal
10 is ground to a suitable grain size to manufacture a coal blend, and a hot working
quality improving additive is mixed with the coal blend and suitably dried, and
then a binder and a curing agent are used, thereby manufacturing final coal
briquettes.
While the coal briquettes are subjected to a storage process after a coal
15 briquette manufacturing process, about 10 to 15 % of powdered coal briquettes
having a grain size equal to or less than a standard grain size, which may not
be charged in the melter gasifier, are generated. The powdered coal
briquettes generated as described above are re-charged to thereby be used in a
raw material treating process or mixing process. The standard grain size of
20 the coal briquettes which may be charged in the melter gasifier may be 5 to
50mm.
The powdered coal briquettes generated in the coal briquette
manufacturing process are about 10 to 15 % of a production amount of the coal
briquettes, such that the powdered coal briquettes account for a large ratio.
3
The powdered coal briquettes as described above are re-charged to thereby be
used in a coking coal charging process or mixing process. However, incidental
expenses consumed to operate and maintain equipment for re-charging are
continuously generated, which increases a manufacturing cost of coal
briquettes. Further, since there are large limitations in a distance and a spa5 ce
from a stock house in which the powdered coal briquettes are generated to a
position at which the coking coal charging process for recharging the coking
coal is performed, investment cost may be large. In addition, various problems
may be generated in equipment configured so as to be re-used, which may
10 lower an operation ratio of a coal briquette manufacturing process.
At the time of re-using the powdered coal briquettes, non-uniformity of
the grain size or moisture content of the powdered coal briquettes causes
quality deviation of the coal briquettes, which acts as a negative factor in stably
managing a coal briquette manufacturing process. Particularly, in the case in
15 which an amount of the powdered coal briquettes is increased at the time of
deterioration of cold working quality, the case in which a production amount of
the coal briquettes is smaller than a required amount in the melter gasifier may
be generated, so an operation ratio of the melter gasifier may not be increased.
In the case of re-use of the powdered coal briquettes in the raw coking coal
20 charging process or mixing process in order to recycle the powdered coal
briquettes as a method used in the existing process, about 5 to 20 wt% of the
powdered coal briquettes are used in the coking coal, which is the same level
as the existing coal briquette production capacity. Therefore, there is no loss
in this process, but the powdered coal briquettes are only recycled.
4
Therefore, in order to solve this problem, an object of the present
invention is to provide a method and a device for manufacturing coal briquettes
that are capable of simplifying an existing powdered coal briquette reusing
process and decreasing incidental expenses consumed for treatment by
adjusting the powdered coal briquettes generated in the process to have 5 a
suitable moisture content and directly molding the powdered coal briquettes to
produce coal briquettes without using an additional binder in a stock house from
which the powdered coal briquettes are charged in the melter gasifier while
simultaneously generating the powdered coal briquettes; capable of decreasing
10 a quality deviation of the coal briquettes by not simultaneously using coking coal
and the powdered coal briquettes; and capable of improving production capacity
in accordance with a generation rate of the powdered coal briquettes as
compared to the existing production capacity of the coal briquettes by directly
charging the powdered coal briquettes together with general coal briquettes in
15 the melter gasifier from the stock house after producing the coal briquettes.
The above information disclosed in this Background section is only for
enhancement of understanding of the background of the invention and therefore
it may contain information that does not form the prior art that is already known
in this country to a person of ordinary skill in the art.
20 SUMMARY OF THE INVENTION
The present invention has been made in an effort to provide a method
and a device for manufacturing coal briquettes having advantages of:
simplifying an existing powdered coal briquette reusing process and decreasing
incidental expenses consumed for treatment by adjusting the powdered coal
5
briquettes generated in a coal briquette manufacturing process to have a
suitable moisture content and directly molding the powdered coal briquettes to
produce coal briquettes without using additional binder in a stock house from
which the powdered coal briquettes are charged in the melter gasifier while
simultaneously generating the powdered coal briquettes; decreasing a quali5 ty
deviation of the coal briquettes by not simultaneously using coking coal and the
powdered coal briquettes; and increasing production capacity in accordance
with a generation rate of the powdered coal briquettes as compared to the
existing production capacity of the coal briquettes by directly charging the
10 powdered coal briquettes together with general coal briquettes in the melter
gasifier from the stock house after producing the coal briquettes.
An exemplary embodiment of the present invention provides a method
for manufacturing coal briquettes including: a coking coal providing step of
providing coking coal having a predetermined grain size;
15 a binder and curing agent providing step of providing a binder and a
curing agent to be mixed with the coking coal;
a mixing step of mixing the coking coal provided in the coking coal
providing step and the binder and curing agent provided in the binder and
curing agent providing step with each other;
20 a first coal briquette manufacturing step of molding mixed coal obtained
by mixing the coking coal, the binder, and the curing agent in the mixing step to
manufacture coal briquettes;
a grain size sorting step of sorting coal briquettes having a grain size
equal to or more than a standard grain size and powdered coal briquettes
6
having a grain size equal to or less than the standard grain size among the coal
briquettes manufactured in the coal briquette manufacturing step; and
a second coal briquette manufacturing step of receiving the powdered
coal briquettes sorted in the grain size sorting step and molding the powdered
coal briquettes to manufacture coal briquettes5 .
The method for manufacturing coal briquettes may further include,
between the first coal briquette manufacturing step and the grain size sorting
step, a coal briquette storing step of storing the coal briquettes manufactured in
the first coal briquette manufacturing step to supply the stored coal briquettes to
10 the grain size sorting step.
The method for manufacturing coal briquettes may further include,
between the grain size sorting step and the second coal briquette
manufacturing step, a moisture adding step of adding moisture to the powdered
coal briquettes so that the powdered coal briquettes sorted in the grain size
15 sorting step may be adjusted to have a suitable moisture content.
In the coking coal providing step, 90 % of coking coal provided to the
mixing step may have a grain size of 5 mm or less.
The binder may be at least one binder selected from a binder group
consisting of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin,
20 and the like.
The curing agent may be at least one curing agent selected from a
group consisting of lime, slaked lime, limestone, calcium carbonate, cement,
bentonite, clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and
oxides.
7
The coal briquettes having a grain size equal to or more than the
standard grain size sorted in the grain size sorting step may be charged in a
melter gasifier.
The coal briquettes manufactured in the second coal briquette
manufacturing step may be supplied to the coal briquette storing step5 .
20 % or more of the powdered coal briquettes may have a grain size of
3 mm or more, and the powdered coal briquettes may have an average grain
size of 1 to 30 mm.
The powdered coal briquettes may have density of 0.9 to 1.6 g/cm3.
10 The powdered coal briquettes may be supplied with moisture from a
moisture addition device to thereby be adjusted to have a suitable moisture
content of 3 to 10 %.
Another exemplary embodiment of the present invention provides a
device for manufacturing coal briquettes, including: a coking coal storage bin
15 storing coking coal having a predetermined grain size;
a binder supply device supplying a binder to be mixed with the coking
coal;
a curing agent supply device supplying a curing agent to be mixed with
the coking coal;
20 a mixing device mixing the coking coal supplied from the coking coal
storage bin, the binder supplied from the binder supply device, and the curing
agent supplied from the curing agent supply device;
a first molding machine manufacturing coal briquettes by molding mixed
coal in which the coking coal, the binder, and the curing agent are mixed by the
8
mixing device;
a grain size sorter sorting coal briquettes having a grain size equal to or
more than the standard grain size and powdered coal briquettes having a grain
size equal to or less than the standard grain size among the coal briquettes
manufactured by the first molding machine; an5 d
a second molding machine manufacturing coal briquettes by molding the
powdered coal briquettes sorted by the grain size sorter.
The device for manufacturing coal briquettes may further include a coal
briquette storage bin provided between the first molding machine and the grain
10 size sorter and storing the coal briquettes manufactured in the first molding
machine to supply the stored coal briquettes to the grain size sorter.
The device for manufacturing coal briquettes may further include a
moisture addition device provided between the grain size sorter and the second
molding machine and adding moisture to the powdered coal briquettes so that
15 the powdered coal briquettes sorted by the grain size sorter may be adjusted to
have a suitable moisture content.
90 % of coking coal stored in the coking coal storage bin may have a
grain size of 5 mm or less.
The binder may be at least one binder selected from a binder group
20 consisting of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin,
and the like.
The curing agent may be at least one curing agent selected from a
group consisting of lime, slaked lime, limestone, calcium carbonate, cement,
bentonite, clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and
9
oxides.
The coal briquettes having a grain size equal to or more than the
standard grain size sorted by the grain size sorter may be charged in a melter
gasifier.
The coal briquettes manufactured by the second molding machine ma5 y
be supplied to the coal briquette storage bin.
20 % or more of the powdered coal briquettes may have a grain size of
3 mm or more, and the powdered coal briquettes may have an average grain
size of 1 to 30 mm.
The powdered coal briquettes may have density of 0.9 to 1.6 g/cm310 .
The powdered coal briquettes may be supplied with moisture from the
moisture addition device to thereby be adjusted to have a suitable moisture
content of 3 to 10 %.
According to an exemplary embodiment of the present invention, an
15 economic burden of operating and maintaining equipment required to transfer
the powdered coal briquettes in order to reuse the powdered coal briquettes
generated in a storage process after manufacturing the coal briquettes may be
decreased, and as a result, it is possible to simplify equipment, such that an
investment cost may be decreased.
20 In addition, according to an exemplary embodiment of the present
invention, since the powdered coal briquettes are not used together with the
coking coal, quality deviation of the coal briquettes due to grain size deviation
and moisture content deviation of the powdered coal briquettes may be
decreased, and since coal briquettes are additionally formed by directly molding
10
the powdered coal briquettes in a place from which the coal briquettes are
charged in the melter gasifier simultaneously with the generation of the
powdered coal briquettes, a production amount per unit time may be increased,
such that efficiency of an overall coal briquette manufacturing process may be
increased5 .
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating an apparent density change of coal
briquettes depending on compression strength.
FIG. 2 is a schematic configuration view of a method for manufacturing
10 coal briquettes according to an exemplary embodiment of the present invention.
FIG. 3 is a schematic configuration view of a device for manufacturing
coal briquettes according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Hereinafter, exemplary embodiments of the present invention will be
15 described in detail with reference to the accompanying drawings so that those
skilled in the art to which the present invention pertains may easily practice the
present invention. As is easily understood by those skilled in the art to which
the present invention pertains, exemplary embodiments to be described below
may be variously changed without departing from the concept and scope of the
20 present invention. Like reference numerals designate like or similar
components.
Hereinafter, used technical terms are only to describe a specific
embodiment, and do not limit the present invention. Singular forms used in the
present specification include plural forms as long as they do not have clearly
11
opposite meanings. The term ‘include’ used in the present specification is to
specify a specific property, region, integer, step, operation, factor, and/or
component, but does not exclude presence or addition of another specific
property, region, integer, step, operation, factor, component, and/or group.
Hereinafter, all terms including technical and scientific terms used in th5 e
present specification have the same meanings as those understood by those
skilled in the art to which the present invention pertains. Terms defined in a
dictionary have a meaning corresponding to a related technology document and
presently disclosed contents, and are not to be analyzed as an ideal or very
10 official meaning unless stated otherwise.
(Problem solving principle of the present invention)
Powdered coal briquettes generated during a coal briquette
manufacturing process may be mainly composed of low quality coal briquettes
generated at an early coal briquettes process, powder coal briquettes generated
15 in a non-molding area except for coal briquettes generated at the time of
molding, and fragmented coal briquettes generated during transfer. A ratio of
the powdered coal briquettes generated after manufacturing coal briquettes is
about 80 % or more, a moisture content of the powdered coal briquettes is
about 1 to 10 %, a ratio of powdered coal briquettes having a grain size of 3 mm
20 or more is 20 %, and an average grain size of the powdered coal briquettes is
about 1 to 30 mm. A density of the powdered coal briquettes is 1.0 to 1.6
g/cm3, which is lower than that of normal coal briquettes, but higher than coking
coal before being molded. In the case of directly molding the powdered coal
briquettes, quality of the coal briquettes may be deteriorated by molding
12
instability, such that there is a problem in usability. In the case of adjusting the
powdered coal briquettes to have a suitable moisture content to directly mold
the powdered coal briquettes to secure cold strength, quality may be secured.
The reason is as follows. Since the powdered coal briquettes are subjected to
a primary molding process, the powdered coal briquettes have a high densi5 ty,
and since these powdered coal briquettes are re-molded, a density of the
remolded coal briquettes may be increased as compared to the existing coal
briquettes, such that quality may be secured.
FIG. 1 is a graph illustrating an apparent density change of coal
10 briquettes depending on compression strength. Compression strength of the
coal briquettes is significantly affected by density, and in the case of using the
same binder and the same curing agent, the higher the density, the higher the
compression strength.
The method according to the present invention, which is a method for
15 suitably adjusting the moisture content of the powdered coal briquettes
generated in a storage process after the coal briquette manufacturing process
and then directly molding the powdered coal briquettes to manufacture coal
briquettes, may increase coal briquettes production capacity and simplify a
powdered coal briquette reusing process to increase efficiency of the coal
20 briquette manufacturing process.
FIG. 2 is a schematic configuration view of a method for manufacturing
coal briquettes according to an exemplary embodiment of the present invention.
Referring to FIG. 2, the method for manufacturing coal briquettes
according to an exemplary embodiment of the present invention may include a
13
coking coal providing step (S10) of providing coking coal having a
predetermined grain size,
a binder and curing agent providing step (S20) of providing a binder and
a curing agent to be mixed with the coking coal,
a mixing step (S30) of mixing the coking coal provided in the coking coa5 l
providing step (S10) and the binder and curing agent provided in the binder and
curing agent providing step (S20) with each other,
a first coal briquette manufacturing step (S40) of molding mixed coal
obtained by mixing the coking coal, the binder, and the curing agent in the
10 mixing step (S30) to manufacture coal briquettes,
a grain size sorting step (S60) of sorting coal briquettes having a grain
size equal to or more than a standard grain size and powdered coal briquettes
having a grain size equal to or less than the standard grain size among the coal
briquettes manufactured in the coal briquette manufacturing step (S40), and
15 a second coal briquette manufacturing step (S80) of receiving the
powdered coal briquettes sorted in the grain size sorting step (S60) and molding
the powdered coal briquettes to manufacture coal briquettes.
The method for manufacturing coal briquettes may further include,
between the first coal briquette manufacturing step (S40) and the grain size
20 sorting step (S60), a coal briquette storing step (S50) of storing the coal
briquettes manufactured in the first coal briquette manufacturing step (S40) to
supply the stored coal briquettes to the grain size sorting step (S60).
The method may further include, between the grain size sorting step
(S60) and the second coal briquette manufacturing step (S80), a moisture
14
adding step (S70) of adding moisture to the powdered coal briquettes so that
the powdered coal briquettes sorted in the grain size sorting step (S60) may be
adjusted to have a suitable moisture content.
In the coking coal providing step (S10), 90 % of coking coal provided to
the mixing step (S30) may have a grain size of 5 mm or less5 .
The binder may be at least one binder selected from a binder group
consisting of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin,
and the like.
The curing agent may be at least one curing agent selected from a
10 group consisting of lime, slaked lime, limestone, calcium carbonate, cement,
bentonite, clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and
oxides.
In the binder and curing agent providing step (S20), a constant amount
(1 to 15 wt%) of the binder may be constantly supplied to the mixing step (S30),
15 and a constant amount of the curing agent may be supplied to the mixing step
(S30).
The mixed coal obtained by mixing the coking coal, the binder, and the
curing agent in the mixing step (S30) may be supplied to the first coal briquette
manufacturing step (S40), and in the first coal briquette manufacturing step
20 (S40), the mixed coal is molded, thereby manufacturing coal briquettes. The
coal briquettes manufactured in the first coal briquette manufacturing step (S40)
may be supplied to and stored in the coal briquette storing step (S50).
The coal briquettes having a grain size equal to or more than the
standard grain size sorted in the grain size sorting step (S60) may be charged
15
in a melter gasifier 10. The standard grain size of the coal briquettes which
may be charged in the melter gasifier may be 5 to 50 mm.
The coal briquettes manufactured in the second coal briquette
manufacturing step (S80) may be supplied to the coal briquette storing step
(S50)5 .
In addition, the powdered coal briquettes may have a moisture content
of 1 to 10 %, 20 % or more of the powdered coal briquettes may have a grain
size of 3 mm or more, and the powdered coal briquettes may have an average
grain size of 1 to 30 mm. The powdered coal briquettes may have a density of
0.9 to 1.6 g/cm310 . The powdered coal briquettes may be supplied with moisture
in the moisture adding step (S70) to thereby be adjusted to have a suitable
moisture content of 3 to 10 %.
FIG. 3 is a schematic configuration view of a device for manufacturing
coal briquettes according to an exemplary embodiment of the present invention.
15 Referring to FIG. 3, a device for manufacturing coal briquettes may
include a coking coal storage bin 1 storing coking coal having a predetermined
grain size,
a binder supply device 2 supplying a binder to be mixed with the coking
coal,
20 a curing agent supply device 3 supplying a curing agent to be mixed
with the coking coal,
a mixing device 4 mixing the coking coal supplied from the coking coal
storage bin, the binder supplied from the binder supply device, and the curing
agent supplied from the curing agent supply device,
16
a first molding machine 5 manufacturing coal briquettes by molding
mixed coal in which the coking coal, the binder, and the curing agent are mixed
by the mixing device,
a grain size sorter 7 sorting coal briquettes having a grain size equal to
or more than the standard grain size and powdered coal briquettes having 5 a
grain size equal to or less than the standard grain size among the coal
briquettes manufactured by the first molding machine, and
a second molding machine 9 manufacturing coal briquettes by molding
the powdered coal briquettes sorted by the grain size sorter 7.
10 The device for manufacturing coal briquettes may further include a coal
briquette storage bin 6 provided between the first molding machine 5 and the
grain size sorter 7 and storing the coal briquettes manufactured in the first
molding machine 5 to supply the stored coal briquettes to the grain size sorter 7.
The device for manufacturing coal briquettes may further include a
15 moisture addition device 8 provided between the grain size sorter 7 and the
second molding machine 9 and adding moisture to the powdered coal
briquettes so that the powdered coal briquettes sorted by the grain size sorter 7
may be adjusted to have a suitable moisture content.
90 % of coking coal stored in the coking coal storage bin 1 may have a
20 grain size of 5 mm or less.
The binder may be at least one binder selected from a binder group
consisting of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin,
and the like.
The binder supply device 2 may supply a constant amount (1 to 15 wt%)
17
of the binder to the mixing device 4.
The curing agent may be at least one curing agent selected from a
group consisting of lime, slaked lime, limestone, calcium carbonate, cement,
bentonite, clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and
oxides5 .
The curing agent supply device 3 may supply a constant amount of the
curing agent to the mixing device 4.
The mixed coal in which the coking coal, the binder, and the curing
agent are mixed may be supplied to the first molding machine 5, and the first
10 molding machine 5 may mold the mixed coal to manufacture coal briquettes.
The coal briquettes manufactured in the first molding machine 5 may be stored
in the coal briquette storage bin 6.
The coal briquettes having a grain size equal to or more than the
standard grain size, sorted by the grain size sorter 7, may be charged in the
15 melter gasifier 10.
The second molding machine 9 may be connected to the coal briquette
storage bin 6, and the coal briquettes manufactured by the second molding
machine 9 may be supplied to the coal briquette storage bin 6.
In addition, a generation amount of the low quality coal briquettes in the
20 coal briquettes produced in the first molding machine 5 or powdered coal
briquettes having a grain size equal to or less than the standard grain size,
generated by drop impact during the transferring and compression load in the
coal briquette storage bin 6 may be 5 to 20 % of the coal briquettes produced in
the first molding machine 5.
18
The powdered coal briquettes may have a moisture content of 1 to 10 %,
20 % or more of the powdered coal briquettes may have a grain size of 3 mm or
more, and the powdered coal briquettes may have an average grain size of 1 to
30 mm. The powdered coal briquettes may have a density of 0.9 to 1.6 g/cm3.
The powdered coal briquettes may be supplied with moisture from the moistur5 e
addition device 8 to thereby be adjusted to have a suitable moisture content of 3
to 10 %. Strength of coal briquettes manufactured in the second molding
machine 9 molding the powdered coal briquettes of which the moisture content
is adjusted may be 95 to 150 % of strength of the existing general coal
10 briquettes. Production capacity of the second molding machine 9 molding the
powdered coal briquettes may be 5 to 30 % of production capacity of the first
molding machine 5.
Hereinafter, an operation of the device for manufacturing coal briquettes
according to an exemplary embodiment of the present invention will be
15 described with reference to FIG. 3.
The coking coal, the binder, and the curing agent are mixed with each
other in the mixing device 4 supplied with the coking coal from the coking coal
storage bin 1 storing coking coal of which 90 % has a grain size of 5 mm or less,
supplied with a constant amount (1 to 15 wt%) of at least one binder selected
20 from the binder group consisting of bitumen, starch, molasses, sodium silicate,
pitch, a polymer resin, and the like from the binder supply device 2, and a
constant amount of at least one curing agent selected from the group consisting
of lime, slaked lime, limestone, calcium carbonate, cement, bentonite, clay,
silica, silicate, dolomite, phosphoric acid, sulfuric acid, and oxides from the
19
curing agent supply device 3.
The mixed coal in which the coking coal, the binder, and the curing
agent are mixed in the mixing device 4 may be supplied to the first molding
machine 5, and the first molding machine 5 may manufacture coal briquettes
from the mixed coal5 .
The coal briquettes manufactured in the first molding machine 5 are
stored in the coal briquette storage bin 6, coal briquettes having a grain size
equal to or more than the standard grain size, sorted by the grain size sorter 7
before being charged in the melter gasifier 10, are charged in the melter gasifier
10 10, powdered coal briquettes having a grain size equal to or less than the
standard grain size are supplied with moisture from the moisture addition device
8 to thereby be adjusted to have a suitable moisture content, and then supplied
to the second molding machine 9, the second molding machine 9 manufactures
coal briquettes from the powdered coal briquettes, and the coal briquettes
15 manufactured in the second molding machine 9 are supplied to the coal
briquette storage bin 6.
Hereinafter, the present invention will be described in detail through
experimental examples.
(Experimental Examples)
20 Coal briquettes were manufactured by a general method, powdered coal
briquettes were separately manufactured depending on characteristics of
powdered coal briquettes actually generated in a coal briquette manufacturing
process, and powdered coal briquettes-derived coal briquettes were
manufactured by the same method for manufacturing coal briquettes using the
20
powdered coal briquettes as a raw material.
In this case, the powdered coal briquettes were adjusted to have an
average grain size of 4 mm and moisture contents of 6 wt%, 8 wt%, and 10 wt%,
respectively. In order to evaluate cold strength of the manufactured coal
briquettes, compression strength was measured5 .
[Table 1]
As illustrated in [Table 1], as a result of manufacturing coal briquettes by
adjusting the moisture content to 6 % in a state in which the powdered coal
10 briquettes had the same grain size in Experimental Example 1, compression
strength was 66.5 kgf, which was increased as compared to compression
strength (58.8 kgf) of the general coal briquettes.
In addition, as a result of manufacturing coal briquettes by adjusting the
moisture content to 8 % as in Experimental Example 2, it was confirmed that
15 compression strength was rapidly increased to 92.2 kgf.
As a result of manufacturing coal briquettes by adjusting the moisture
21
content to 10 % as in Experimental Example 3, compression strength was 45.6
kgf, which was slightly decreased as compared to the general coal briquettes,
but it may be judged that there was no severe problem in usability.
While this invention has been described in connection with what is
presently considered to be practical exemplary embodiments, it is to b5 e
understood that the invention is not limited to the disclosed embodiments, but,
on the contrary, is intended to cover various modifications and equivalent
arrangements included within the spirit and scope of the appended claims.
10
1: coking coal storage bin 2: binder supply device
3: curing agent supply device 4: mixing device
5: first molding machine 6: coal briquette storage bin
7: grain size sorter 8: moisture addition device
15 9: second molding machine 10: melter gasifier

WHAT IS CLAIMED IS:
1. A method for manufacturing coal briquettes, the method
comprising:
a coking coal providing step of providing coking coal having 5 a
predetermined grain size;
a binder and curing agent providing step of providing a binder and a
curing agent to be mixed with the coking coal;
a mixing step of mixing the coking coal provided in the coking coal
10 providing step and the binder and curing agent provided in the binder and
curing agent providing step with each other;
a first coal briquette manufacturing step of molding mixed coal obtained
by mixing the coking coal, the binder, and the curing agent in the mixing step to
manufacture coal briquettes;
15 a grain size sorting step of sorting coal briquettes having a grain size
equal to or more than a standard grain size and powdered coal briquettes
having a grain size equal to or less than the standard grain size among the coal
briquettes manufactured in the coal briquette manufacturing step; and
a second coal briquette manufacturing step of receiving the powdered
20 coal briquettes sorted in the grain size sorting step and molding the powdered
coal briquettes to manufacture coal briquettes.
2. The method of claim 1, further comprising,
between the first coal briquette manufacturing step and the grain size
23
sorting step, a coal briquette storing step of storing the coal briquettes
manufactured in the first coal briquette manufacturing step to supply the stored
coal briquettes to the grain size sorting step.
3. The method of claim 1 or 2, further comprising5 ,
between the grain size sorting step and the second coal briquette
manufacturing step, a moisture adding step of adding moisture to the powdered
coal briquettes so that the powdered coal briquettes sorted in the grain size
sorting step are adjusted to have a suitable moisture content.
10
4. The method of claim 3, wherein,
in the coking coal providing step, 90 % of the coking coal provided to the
mixing step has a grain size of 5 mm or less.
15 5. The method of claim 4, wherein
the binder is at least one binder selected from a binder group consisting
of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin, and the
like.
20 6. The method of claim 5, wherein
the curing agent is at least one curing agent selected from a group
consisting of lime, slaked lime, limestone, calcium carbonate, cement, bentonite,
clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and oxides.
24
7. The method of claim 6, wherein
the coal briquettes having a grain size equal to or more than the
standard grain size, sorted in the grain size sorting step, are charged in a melter
gasifier.
5
8. The method of claim 3, wherein
the coal briquettes manufactured in the second coal briquette
manufacturing step are supplied to the coal briquette storing step.
10 9. The method of claim 4, wherein
20 % or more of the powdered coal briquettes have a grain size of 3 mm
or more, and the powdered coal briquettes have an average grain size of 1 to
30 mm.
15 10. The method of claim 9, wherein
the powdered coal briquettes have density of 0.9 to 1.6 g/cm3.
11. The method of claim 10, wherein
the powdered coal briquettes are supplied with moisture from a moisture
20 adding device to thereby be adjusted to have a suitable moisture content of 3 to
10 %.
12. A device for manufacturing coal briquettes, the device
comprising:
25
a coking coal storage bin storing coking coal having a predetermined
grain size;
a binder supply device supplying a binder to be mixed with the coking
coal;
a curing agent supply device supplying a curing agent to be mixed wi5 th
the coking coal;
a mixing device mixing the coking coal supplied from the coking coal
storage bin, the binder supplied from the binder supply device, and the curing
agent supplied from the curing agent supply device;
10 a first molding machine manufacturing coal briquettes by molding mixed
coal in which the coking coal, the binder, and the curing agent are mixed by the
mixing device;
a grain size sorter sorting coal briquettes having a grain size equal to or
more than a standard grain size and powdered coal briquettes having a grain
15 size equal to or less than the standard grain size among the coal briquettes
manufactured by the first molding machine; and
a second molding machine manufacturing coal briquettes by molding the
powdered coal briquettes sorted by the grain size sorter.
20 13. The device of claim 12, further comprising
a coal briquette storage bin provided between the first molding machine
and the grain size sorter and storing the coal briquettes manufactured in the first
molding machine to supply the stored coal briquettes to the grain size sorter.
26
14. The device of claim 12 or claim 13, further comprising
a moisture addition device provided between the grain size sorter and
the second molding machine and adding moisture to the powdered coal
briquettes so that the powdered coal briquettes sorted by the grain size sorter
are adjusted to have a suitable moisture content5 .
15. The device of claim 14, wherein
90 % of the coking coal stored in the coking coal storage bin has a grain
size of 5 mm or less.
10
16. The device of claim 15, wherein
the binder is at least one binder selected from a binder group consisting
of bitumen, starch, molasses, sodium silicate, pitch, a polymer resin, and the
like.
15
17. The device of claim 16, wherein
the curing agent is at least one curing agent selected from a group
consisting of lime, slaked lime, limestone, calcium carbonate, cement, bentonite,
clay, silica, silicate, dolomite, phosphoric acid, sulfuric acid, and oxides.
20
18. The device of claim 17, wherein
the coal briquettes having a grain size equal to or more than the
standard grain size, sorted by the grain size sorter, are charged in a melter
gasifier.
27
19. The device of claim 14, wherein
the coal briquettes manufactured by the second molding machine are
supplied to the coal briquette storage bin.
5
20. The device of claim 15, wherein
20 % or more of the powdered coal briquettes have a grain size of 3 mm
or more, and the powdered coal briquettes have an average grain size of 1 to
30 mm.
10
21. The device of claim 20, wherein
the powdered coal briquettes have density of 0.9 to 1.6 g/cm3.
22. The device of claim 21, wherein
15 the powdered coal briquettes are supplied with moisture from the
moisture addition device to thereby be adjusted to have a suitable moisture
content of 3 to 10 %.