METHOD OF PRODUCING HIGH-STRENGTH COKE
Technical Field
[0001]
5 The present invention relates to a method of producing high-strength coke and,
in particular, to a method of producing high-strength blast furnace coke.
Priority is claimed on Japanese Patent Application No. 2009-266567, filed
November 24, 2009, the content of which is incorporated herein by reference. .
10 Background Art
[0002]
Coke used as a reducing agent in blast furnace operation requires a desired
strength for securing permeability in a furnace. In order to produce high-strength coke,
as a raw material of coke, high-quality strongly caking coal is required. However,
15 high-quality strongly caking coal resources are limited.
[0003]
Accordingly, hitherto, many techniques of producing high-strength coke using
low-quality non-caking or slightly caking coal have been proposed.
In a case where coke is produced using non-caking coal or slightly caking coal,
20 when an additive with a caking property (caking additive) is added, the coke strength is
improved (for example, refer to Patent Documents 1 and 2).
[0004]
Typically, as the caking additive, tar, pitch, petroleum caking additives, or the
like are used. It is preferable that caking additives such as tar which are liquid at
25 normal temperature be uniformly kneaded into raw coal. In addition, caking additives
such as pitch which are solid at normal temperature are preferably heated to melting
point or higher in order to liquefy them and kneaded into raw coal (for example, refer to
Patent Document 3).
[0005]
30 However, liquid caking additives can cause operational problems such as pipe
clogging or adherence to the inside of a kneading machine and thus are difficult to handle.
In addition, solid caking additives require a heating device in order to liquefy them and
therefore, there is a problem that the production cost is increased due to increased facility
2
and operational costs.
[0006]
In consideration of these problems, methods of producing coke in which a solid
caking additive is crushed and then mixed into raw coal in the solid state have been
5 proposed (refer to Patent Documents 4 and 5).
More specifically, for example, Patent Document 4 discloses a method of
producing high-strength coke in which a solid caking additive, 50% or more of which is
made up of fine particles with a particle size less than 3 mm, is mixed with raw coal in
the solid state, charged into a coke oven as it is, and then dry-distilled. According to the
10 method disclosed in Patent Document 4, solid caking additive is uniformly dispersed in
particles of coal and thus a strong coke structure can be obtained.
In addition, Patent Document 4 also discloses that it is preferable that the
granularity of the solid caking additive be as small as possible because fine particles with
a particle size of 0.3 mm or less aggregate easily.
15 [0007]
In addition, a method of producing a blast furnace coke in which a mixture of
low-rank blended coal, which is dried to have a moisture of 5% or less, and bituminous
hydrocarbons is used as a charging coke oven blended coal, has been proposed (for
example, refer to Patent Document 6). According to the method disclosed in Patent
20 Document 6, as the coal charge has a large bulk density, a strong coke structure can be
obtained.
Related Art Documents
Patent Documents
.25 [0008]
[Patent Document 1] Japanese Unexamined Patent Application, First Publication No.
H II-241072
[Patent Document 2] Japanese Unexamined Patent Application, First Publication No.
2001-262155
30 [Patent Document 3] Japanese Unexamined Patent Application, First Publication No.
S57-67686
[Patent Document 4] Japanese Unexamined Patent Application, First Publication No.
2007-002052
3
[Patent Document 5] Japanese Unexamined Patent Application, First Publication No.
2007-063350
[Patent Document 6] Japanese Unexamined Patent Application, First Publication No.
S51-41701
5
Disclosure of the Invention
Problems to be Solved by the Invention
[0009]
However, when a solid caking additive is crushed to be used in the solid state,
10 fine particles with a particle size of 0.3 mm or less are generated during crushing. As
described above, the fine particles with a particle size of 0.3 mm or less aggregate easily.
Quasi-particles formed by aggregation of fine particles of solid caking additive with a
particle size of 0.3 mm or less do not collapse easily even when mixed with raw coal and
grow whilst being mixed with raw coal. As a result, the dispersibility of the solid
15 caking additive in the raw coal may be deteriorated. Therefore, even when solid caking
additive which is finely crushed to contain fine particles with a particle size of, for
example, less than 3 mm is used as a solid caking additive, the dispersibility of the solid
caking additive in the raw coal can not be effectively improved. Therefore, in the
related art, a coke strength improvement effect obtained by finely crushing the solid
20 caking additive is insufficient.
[0010]
As described above, in the related art, when coke is produced using taw coal in
which a large amount of low-quality raw coal (non-caking or slightly caking coal) is
blended and solid caking additive containing fine particles with a particle size of 0.3 mm
25 or less, coke having a sufficient strength may not be obtained. Therefore, in the related
art, when solid caking additive is crushed for use, it is crushed such that as few fine
particles with a particle size of 0.3 mm or less as possible are formed, or such that when
they are formed, as few fine particles as possible are used.
[0011]
30 An object of the present invention is to provide a method of producing
high-strength coke in which, even when low-quality coal, in which a large amount of
non-caking coal or slightly caking coal is blended, is used as raw coal, high-strength coke
can be produced using raw coal and solid caking additive containing fine particles with a
4
particle size of 0.3 mm or less.
Means for Solving the Problems
[0012]
5 In order to solve the above-described problems, the present inventors discussed
the following.
That is, the present inventors paid attention to the dispersibility of a crushed
caking additive in raw coal and the coke strength, crushed a solid caking additive to
obtain a crushed caking additive containing fine particles with a particle size of 0.3 mm
10 or less, and optimized a moisture of a mixture which was obtained by mixing the crushed
caking additive with low-quality raw coal such as non-caking coal or slightly caking coal
and optimized a content of fine particles with a particle size of 0.3 mm or less which are
included in the crushed caking additive.
[0013]
15 As a result, it was determined that, when a solid caking additive is crushed to
obtain a crushed caking additive containing fine particles with a particle size of 0.3 mm
or less and then the crushed caking additive is mixed with raw coal to obtain a mixture, a
moisture of the mixture and a content of the fine particles with a particle size of 0.3 mm
or less which are included in the crushed caking additive and aggregate to form
20 quasi-particles have a large effect on the dispersibility, which determines the coke
strength, of the crushed caking additive in the raw coal. In addition, it was found that,
the larger the content of the fine particles with a particle size of 0.3 mm or lcss, the
higher the coke strength.
[0014]
-25 In addition, it was found that the following effects can be obtained by adjusting
the content of the fine particles with a particle size of 0.3 mm or less which are included
in the crushed caking additive and the moisture of the mixture to be in a predetermined
range: the quasi-particles formed when the fine particles of the solid caking additive with
a particle size of 0.3 mm or less aggregate have a particle size suitable for mixing with
30 the raw coal and thus the crushed caking additive can be uniformly dispersed in the raw
coal; and the bulk density of the mixture can be improved and thus high-strength coke
can be obtained.
[0015]
5
Specifically, it was found that when a crushed caking additive containing 50%
by mass or more of fine particles with a particle size of 0.3 mm or less is mixed with raw
coal to obtain a mixture, the moisture of the mixture may be adjusted to be less than or
equal to 8% by mass; and when a crushed caking additive containing 30% by mass or
5 more of fine particles with a particle size of 0.3 mm or less is mixed with raw coal to
obtain a mixture, the moisture of the mixture may be adjusted to be less than or equal to
7% by mass.
The present invention has been made on the basis of the findings described
above, and the summary thereof is as follows.
10 [0016]
(1) A method of producing high-strength coke including:
a crushing process of crushing a solid caking additive to form a crushed caking
additive containing 50% by mass to 100% by mass of fine particles with a particle size of
0.01 mm to 0.3 mm;
15 a mixing process of mixing the crushed caking additive and raw coal with each
other to prepare a mixture;
a dry-distillation process of dry-distilling the mixture; and
a drying process which is performed before the mixing process, in parallel with
the mixing process, or before the dry-distillation process and after the mixing process,
20 wherein when the drying process is performed before the mixing process, the
raw coal is dried to adjust the moisture of the mixture of the mixing process in a range of
0% by mass to 8% by mass in the drying process,
when the drying process is performed in parallel with the mixing process, the
crushed caking additive and the raw coal are dried while being mixed with each other to
25 form the-mixture with a moisture of 0% by mass to 8% by mass in the drying process,
and
when the drying process is performed before the dry-distillation process and
after the mixing process, the mixture is dried to adjust the moisture of the mixture in a
range of 0% by mass to 8% by mass in the drying process.
30 [0017]
(2) A method of producing high-strength coke including:
a crushing process of crushing a solid caking additive to form a crushed caking
additive containing 30% by mass to 100% by mass of fine particles with a particle size of
6
0.01 mm to 0.3 mm;
a mixing process of mixing the crushed caking additive and raw coal with each
other to prepare a mixture;
a dry-distillation process of dry-distilling the mixture; and
5 a drying process which is performed before the mixing process, in parallel with
the mixing process, or before the dry-distillation process and after the mixing process,
wherein when the drying process is performed before the mixing process, the
raw coal is dried to adjust the moisture of the mixture of the mixing process in a range of
0% by mass to 7% by mass in the drying process,
10 when the drying process is performed in parallel with the mixing process, the
crushed caking additive and the raw coal are dried while being mixed with each other to
form the mixture with a moisture of 0% by mass to 7% by mass in the drying process,
and
when the drying process is performed before the dry-distillation process and
15 after the mixing process, the mixture is dried to adjust the moisture of the mixture in a
range of 0% by mass to 7% by mass in the drying process.
[0018]
In addition, fine particles of the solid caking additive with a particle size of 0.3
mm or less, which are obtained by crushing a solid caking additive, are dispersed as dust
20 during transportation or when a mixture of the crushed caking additive and raw coal is
charged into a coke oven used in the dry-distillation process. The particle emission
(dust dispersal) phenomenon is a phenomenon in which fine particles included in a solid
caking additive float in the air like smoke. The dispersal of the fine particles of the
solid caking additive pollutes the production environment. Therefore, the present
25 inventors paid attention to the particle emission (dust dispersal) phenomenon.
In order for the dispersal of the fine particles of the solid caking additive not to
pollute the production environment, as a method of preventing the particles from being
dispersed as dust and maintaining the quality of the environment, a method of adding
moisture to a mixture of a crushed solid caking additive or crushed caking additive and
30 raw coal to prevent the particles from being dispersed as dust was considered.
[0019]
However, when moisture is added to the fine particles of the solid caking
additive with a particle size of 0.3 mm or less in order to prevent the fine particles from
7
being dispersed as dust, the fine particles of the solid caking additive aggregate to form
quasi-particles. Therefore, a coke strength improvement effect obtained by finely
crushing the solid caking additive is insufficient . In addition , when moisture is added in
order to prevent the fine particles of the solid caking additive from being dispersed as
5 dust, the bulk density of the mixture of the crushed caking additive and the raw coal
deteriorates and thus there is a case where the coke strength is insufficient.
[0020]
Therefore, the present inventors paid attention to the dispersal of the fine
particles of the solid caking additive with a particle size of 0.3 mm or less and optimized
10 a moisture of a mixture obtained by mixing a crushed caking additive , which is obtained
by crushing a solid caking additive, with raw coal and drying the resultant; a moisture of
a mixture obtained by mixing a crushed caking additive with a dried raw coal; and a
moisture of a mixture obtained by drying a crushed caking additive and raw coal while
being mixed with each other.
15 As a result, it was found that , by adjusting the moisture of the mixtures to be
equal to or greater than 6% by mass, the fine particles are prevented from being dispersed
as dust.
[00211
(3) The method of producing high-strength coke according to (1) or (2) above
20 may further include a moisture adjustment process of adding moisture such that a
moisture of the mixture is equal to or greater than 6% by mass before the dry-distillation
process and after the drying process.
[0022]
(4) In the method of producing high-strength coke according to (1) or (2)
-25 above, in the crushing process, a crushed caking additive containing 80% by mass or
more of particles with a particle size of 3 mm or less may be formed.
(5) In the method of producing high-strength coke according to (1) or (2)
above, the raw coal may contain 20% by mass to 60% by mass of one or both of slightly
caking coal and non-caking coal.
30 (6) In the method of producing high-strength coke according to (1) or (2)
above, in the drying process, the mixture is heated at a temperature equal to or lower than
a softening point of the solid caking additive.
8
Effects of the Invention
[00231
According to the above-described aspects of the present invention, even when
low-quality coal, in which a large amount of non-caking coal or slightly caking coal is
5 blended, is used as raw coal, a crushed caking additive containing fine particles with a
particle size of 0.3 mm or less can be uniformly dispersed in raw coal and the bulk
density of the mixture of the crushed caking additive and the raw coal can be improved.
Therefore, high-strength coke can be produced.
10 Brief Description of Drawings
[0024]
FIG 1 is a flowchart illustrating methods of producing high-strength coke
according to first and second embodiments, which are examples of a method of
producing high-strength coke according to the present invention.
15 FIG 2 is a flowchart illustrating a method of producing high-strength coke
according to a third embodiment, which is an example of a method of producing
high-strength coke according to the present invention.
FIG 3 is a flowchart illustrating a method of producing high-strength coke
according to a fourth embodiment, which is an example of a method of producing
20 high-strength coke according to the present invention.
FIG. 4 is a graph illustrating the relationship between a strength (DI(15)), a
moisture of a mixture, and a content of fine particles with a particle size of 0.01 mm to
0.3 mm which are included in a crushed caking additive with regard to cokes of
Examples 1-1 to 1-18 and 2-1 to 2-6, and Comparative Examples 1-1 to 1-5, 2-1 to 2-3,
-25 3-1 to 3-9, and 4-1 to 4-5.
FIG 5 is a graph illustrating the relationship between particle emission times and
moisture of mixtures of Examples 1-1 to 1-18 and 2-1 to 2-6, and Comparative Examples
1-1 to 1-5, 2-1 to 2-3, 3-1 to 3-9, and 4-1 to 4-5.
30 Embodiments of the Invention
[0025]
The respective embodiments of the present invention will be described in detail.
Based on an idea that, if a crushed caking additive which is a solid caking
9
additive in the solid state, which contains fine powder (fine particles with a particle size
of 0.3 mm or less) that form quasi-particles, can be uniformly dispersed in raw coal and
mixed, the fine particles with a particle size of 0.3 mm or less which are not used in the
related art can be used and the coke strength can be further increased, the present
5 inventors have studied in depth a method of uniformly mixing a solid caking additive
containing fine particles with a particle size of 0.3 mm or less with raw coal.
[0026]
The present inventors have examined in depth the characteristics of the,
quasi-particles which are formed by the fine particles of the solid caking additive. As a
10 result, the following (x) to (z) were determined.
(x) A thin film of water is formed on the surface of the fine particles of the
solid caking additive. This thin film of water acts to enhance the aggregation between
the fine particles, and thus quasi particles which do not collapse easily are formed.
[0027]
15 (y) The thin film of water which is formed on the surface of the fine particles
of the solid caking additive disappears easily by heating it. In addition, when the thin
film of water which is formed on the surface of the fine particles disappears, the
quasi-particles collapse easily.
(z) By adjusting a moisture in the solid caking additive which contains the fine
20 particles that form quasi-particles and/or a moisture in a mixture of the solid caking
additive, which contains the fine particles that form quasi-particles, and raw coal, the
quasi-particles can have a size (particle size) which can prevent the fine particles of the
solid caking additive from being dispersed as dust and which is suitable for uniform
mixing with the raw coal.
.25 {0028]
According to the above findings (x) to (z), if, before mixing the solid caking
additive with the raw coal, in parallel with mixing the solid caking additive with the raw
coal, and after mixing the solid caking additive with the raw coal, quasi-particles are
formed by fine particles of a solid caking additive, which have a particle size capable of
30 being uniformly mixed with the raw coal, the fine particles can be prevented from being
dispersed as dust and the solid caking additive which contains fine particles with a
particle size of 0.3 mm or less that form quasi-particles can be uniformly dispersed in the
raw coal. As a result, high-strength coke can be obtained.
10
[0029]
In addition, the present inventors crushed the solid caking additive and mixed
with the raw coal using a crusher while changing the crushing conditions, and then the
content (% by mass) of fine particles with a particle size of 3 mm or less and the content
5 (% by mass) of fine particles with a particle size of 0.3 mm or less which are included in
the crushed solid caking additive were measured.
As a result, in the crushed solid caking additive, when the content of the fine
particles with a particle size of 0.3 mm or less is equal to or greater than 30% by mass,
the content of the fine particles with a particle size of 3 mm or less is equal to or greater
10 than 80% by mass. The content change of the fine particles with a particle size of 3 mm
or less is small. On the other hand, the content change of the fine particles with a
particle size of 0.3 mm or less is large even in a region where the content of the fine
particles with a particle size of 3 mm or less is equal to or greater than 80% by mass.
[0030]
15 Accordingly, the present inventors adopted the content (% by mass) of the fine
particles of the solid caking additive with a particle size of 0.3 mm or less as an index for
evaluating the characteristics of the crushed solid caking additive (crushed caking
additive), that is, as an index for evaluating a quasi-particle forming ability (characteristic
index of the solid caking additive).
20 [0031]
In addition, by crushing the solid caking additive to obtain a crushed calving
additive containing fine particles with a particle size of 0.3 mm or less, mixing 2% by
mass of the crushed caking additive with raw coal to obtain a mixture, drying the mixture
using a drying machine to obtain a dry mix with a moisture of 7% by mass, and
25 dry-distilling the dry mix to produce coke, the present inventors examined the
relationship between the characteristic index of the solid caking additive (the content of
the fine particles of the solid caking additive with a particle size of 0.3 mm or less) and a
quality index of the coke. Here, as the quality index of the coke, the weight percentage
of a 15-mm square hole or more after 150 revolutions (hereinafter, referred to as DI(15))
30 according to a drum method for testing rotational strength defined by JIS K2151 was
used.
[0032]
As a result, when the crushed caking additive contained 33.9% by mass of fine
11
particles with a particle size of 0.3 mm or less, it was possible to secure a high coke
strength (DI(15)). In addition, when the content of the fine particles with a particle size
of 0.3 mm or less which are included in the crushed caking additive is increased from
33.9% by mass to 48.3% by mass, the coke strength (DI(15)) was improved.
5 It can be inferred that the improvements of the coke strength (DI(15)) and the
other qualities which are obtained by increasing the content of the fine particles with a
particle size of 0.3 mm or less included in the crushed caking additive are caused because
with an appropriate moisture, the fine particles form quasi-particles which have particle
sizes suitable for mixing with the raw coal and thus the crushed caking additive is
10 uniformly dispersed in the raw coal.
[0033]
In this embodiment, the basic technical idea is to adjust the following contents in
a desired range: (i) the content of fine powder which forms quasi-particles after
aggregation, that is, the content of fine particles with a particle size of 0.01 mm to 0.3
15 mm which are included in the crushed caking additive obtained by crushing the solid
caking additive; and (ii) the moisture of the mixture obtained by mixing the crushed
caking additive and the raw coal.
[0034]

20 FIG 1 is a flowchart illustrating a method of producing high-strength coke
according to a first embodiment, which is an example of a method of producing
high-strength coke according to the present invention.
As illustrated in FIG 1, a method of producing high-strength coke according to
the first embodiment includes a crushing process S 1, a raw coal crushing process S2, a
.25 mixing process S3, a drying process S4, a moisture adjustment process S5, and a
dry-distillation process S6.
[0035]
As illustrated in FIG 1, the crushing process Si is a process of crushing a solid
caking additive x to obtain a crushed caking additive which contains 50% by mass to
30 100% by mass of fine particles with a particle size of 0.01 mm to 0.3 mm. The crushed
caking additive uses the solid caking additive x which is not subjected to any change
except crushing (which is in the solid state).
[0036]
12
In this embodiment, in order to obtain coke having a sufficient strength, the
content of the fine particles with a particle size of 0.01 mm to 0.3 mm included in the
crushed caking additive is adjusted to be equal to or greater than 50% by mass . Here, it
is more preferable that the content of the fine particles with a particle size of 0.3 mm or
5 less included in the crushed caking additive be greater because the crushed caking
additive can be more uniformly dispersed in the raw coal to thereby improve the coke
strength.
In addition, it is more preferable that the fine particles with a particle size of 0.3
mm or less included in the crushed caking additive have a finer particle size because the
10 coke strength can be further improved. However, in order to efficiently distinguish
particle sizes using a sieve, the particle size is adjusted to be equal to or greater than 0.01
mm. In addition, when the fine particles with a particle size of 0.3 mm or less included
in the crushed caking additive have a finer particle size, dust dispersal is more likely to
occur during transportation or when the mixture of the crushed caking additive and the
15 raw coal is charged into a coke oven used in the dry-distillation process. Therefore, a
particle size equal to or greater than 0.01 mm is preferable.
[0037]
In addition, in the crushing process S 1, in order to more uniformly disperse the
crushed caking additive in the raw coal, it is preferable that the crushed caking additive
20 contain 80% by mass or more of the particles with a particle size of 3 mm or less.
As the solid caking additive x, petroleum pitch, coal pitch, or the like which is
available in large amounts can be used, and a softening point thereof is preferably equal
to or lower than 180°C and preferably equal to or lower than 140°C.
[0038]
-25 As illustrated in FIG 1, the raw coal crushing process S2 is a process of, before
the mixing process S3, crushing raw coal y to contain 75% by mass or more of particles
with a particle size of 3 mm or less and contain 0% by mass to 30% by mass of fine
particles with a particle size of 0.01 mm to 0.3 mm.
The fine particles of the raw coal y preferably have a particle size of 0.3 mm or
30 less in order to more uniformly disperse the crushed caking additive in the raw coal and
preferably have a particle size of 0.01 mm or more so as to efficiently distinguish particle
sizes using a sieve. In addition, when the raw coal y contains fine particles with particle
sizes in the above-described range, the crushed caking additive can be more uniformly
13
dispersed in the raw coal, which is preferable. However, dust dispersal is likely to occur
during transportation or when the mixture of the crushed caking additive and the raw coal
is charged into a coke oven used in the dry-distillation process. Accordingly, the
content of the fine particles with particle sizes in the above-described range is preferably
5 less than or equal to 30% by mass in the raw coal y.
[0039]
The raw coal crushing process S2 may not be performed, but by performing the
raw coal crushing process S2, the crushed caking additive can be more uniformly
dispersed in the raw coal. In addition, in the raw coal crushing process S2, in order to
10 more uniformly disperse the crushed caking additive in the raw coal, it is more preferable
that the raw coal y be crushed to contain 100% by mass of particles with a particle size of
3 mm or less.
[0040]
In addition, the raw coal y preferably contains 20% by mass to 60% by mass of
15 one or both of slightly caking coal and non-caking coal. When the content of one or
both of slightly caking coal and non-caking coal which are included in the raw coal y is
equal to or greater than 20% by mass, an effect of reducing an amount of strongly caking
coal used for the raw coal y can be sufficiently obtained.
In addition, when the content of one or both of slightly caking coal and
20 non-caking coal which are included in the raw coal y is greater than 60% by mass, a coke
strength equal to or greater than 85 (DI(15)) is difficult to obtained even if the caking
additive is added.
[0041]
The mixing process S3 is a process of mixing the crushed caking additive as the
-25 solid caking additive that is in the form of a solid and contains fine particles with a
particle size of 0.3 mm or less which form quasi-particles after aggregation, with the raw
coal crushed in the raw coal crushing process S2 to obtain a mixture.
A mixing ratio of the crushed caking additive and the raw coal is not particularly
limited. However, when the raw coal y containing 20% by mass to 60% by mass of one
30 or both of slightly caking coal and non-caking coal is used, a range of 0.5% by mass:
100% by mass (crushed caking additive:raw coal) to 5% by mass:100% by mass is
preferable in order to secure a coke strength equal to or greater than 85 (DI(15)).
[0042]
14
The drying process S4 is a process of drying the mixture using a drying machine
to obtain a dry mix with a moisture of 0% by mass to 8% by mass.
When the moisture of the dry mix is excessive, the quasi-particles which are
obtained when the fine particles with a particle size of 0.3 mm or less included in the
5 solid caking additive aggregate grow to have a size (particle size) exceeding that suitable
for uniform mixing with the raw coal, which causes coarsening of the quasi-particles and
unevenness in the size (particle size) of the quasi particles. Therefore, it becomes
difficult to uniformly disperse the solid caking additive in the raw coal. As a result, the
coke strength deteriorates and the unevenness of the coke strength is increased.
10 [0043]
The moisture of the dry mix which is required for forming the quasi-particles of
the solid caking additive to have a size (particle size) suitable for uniform mixing with
the raw coal, depends on the kind of solid caking additive and the content, serving as the
characteristic index, of fine particles with a particle size of 0.3 mm or less included in the
15 crushed caking additive which is obtained by crushing the solid caking additive.
[0044]
When the moisture of the dry mix exceeds 8% by mass, the quasi-particles with
a particle size suitable for mixing with the raw coal cannot be formed and it is difficult to
uniformly disperse the crushed caking additive in the raw coal. As a result, the coke
20 strength is insufficient. In order to more uniformly disperse the crushed caking additive
in the raw coal, it is preferable that the moisture of the dry mix be lower. Specifically, it
is more preferable that the moisture be less than or equal to 7% by mass.
[0045]
In addition, the moisture of the dry mix may be 0% by mass. However, 6% by
25 mass or more is preferable in order to reduce the time required for drying the mixture,
perform the drying process S4 efficiently, and prevent dust dispersal from occurring
during transportation or when the dry mix is charged into a coke oven. When the
moisture of the dry mix is equal to or greater than 6% by mass, dust dispersal can be
prevented sufficiently without performing the moisture adjustment process S5 of adding
30 moisture such that the moisture of the dry mix is equal to or greater than 6% by mass,
before the dry-distillation process S6 and after the drying process S4. Therefore, coke
can be produced efficiently compared with a case where the moisture adjustment process
S5 is performed.
15
[0046]
In the drying process S4, it is preferable that the mixture be heated at a
temperature equal to or lower than a softening point of the solid caking additive. As a
result, the dry mix can be obtained efficiently by heating the mixture at a temperature
5 where the solid caking additive is not liquefied or fused. Specifically, a temperature of
heating the mixture in the drying process S4 is preferably equal to or lower than 100°C.
In addition, in order to dry the mixture efficiently, the temperature of heating the mixture
in the drying process S4 is preferably equal to or higher than 50°C.
[0047]
10 The moisture adjustment process S5 is a process of adding moisture such that
the moisture of the dry mix is equal to or greater than 6% by mass, before the
dry-distillation process S6 and after the drying process than. By performing the
moisture adjustment process S5, fine particles with a particle size of 0.3 mm or less
included in the crushed caking additive of the dry mix can be prevented from being
15 dispersed as dust. In addition, the moisture adjustment process S5 may not be
performed when the moisture of the dry mix after the drying process S4 is equal to or
greater than 6% by mass or when there is no need to prevent dust dispersal.
[0048]
When the moisture of the dry mix is equal to or greater than 6% by mass, the
20 quasi-particles formed when fine particles with a particle size of 0.3 mm or less included
in the solid caking additive aggregate do not collapse and thus dust dispersal does not
occur. However, when the moisture of the dry mix is less than 6% by mass, the
quasi-particles of the solid caking additive collapse and the fine particles are generated in
large amounts and thus the particle emission (dust dispersal) phenomenon occurs.
25 Therefore, it is inferred that the moisture of the dry mix which is required for preventing
the fine particles of the solid caking additive from being dispersed as dust is equal to or
greater than 6% by mass.
[0049]
When the quasi-particles of the solid caking additive collapse and, the fine
30 particles are emitted in large amounts, the solid caking additive in the dry mix disappears
and thus the work environment is polluted. Therefore, from the viewpoint of
suppressing the particle emission (dust dispersal) phenomenon from occurring when the
dry mix obtained by mixing the solid caking additive and the raw coal is charged into a
16
coke oven, it is preferable to perform the moisture adjustment process S5 such that the
moisture of the dry mix is equal to or greater than 6% by mass. By adjusting the
moisture of the dry mix to be equal to or greater than 6% by mass, the particle emission
time when the dry mix is charged into a coke oven can be made to be equal to or shorter
5 than 16 seconds, which is the reference value of the Clean Air Act in the United States.
[0050]
As described above, fine particles with a particle size of 0.3 mm or less included
in the solid caking additive can be treated as the fine particles that form quasi-particles.
The reason thereof will be described using Table 1.
10 Table 1 shows the result of measuring a granularity distribution of collected dust
of coal charge (mixture of the solid caking additive and the raw coal) with a moisture of
5.3% by mass.
[0051]
[Table 1 ]
15
[0052]
The coal charge illustrated in Table 1 has a moisture (humidity-controlled
moisture) less than or equal to 6% by mass and thus particle emission occurs when it is
charged into a coke oven. In addition, it is considered that the collected dust of the coal
20 charge illustrated in Table 1 is generated when the quasi-particles formed by the fine
particles of the solid caking additive collapse. As shown in Table 1, the granularity of
the collected dust is less than or equal to 300 μm (=0.3 mm; refer to the particle size in
the leftmost column). Accordingly, it can be inferred that the fine particles with a
particle size of 0.3 mm or less form the quasi-particles. Therefore, the fine particles
25 with a particle size of 0.3 mm or less included in the solid caking additive can be handled
as the fine particles that form quasi-particles.
[0053]
The dry-distillation process S6 is a process of dry-distilling the dry mix. The
dry mix can be dry-distilled using a coke oven. As illustrated in FIG 1, coke z is
30 obtained by performing the dry-distillation process S6.
[0054]
The method of producing high-strength coke according to this embodiment
includes the crushing process S 1 of crushing the solid caking additive to obtain the
17
crushed caking additive containing 50% by mass to 100% by mass of the fine particles
with a particle size of 0.01 mm to 0.3 mm , the mixing process S3 of mixing the crushed
caking additive and the raw coal to obtain the mixture, and the dry -distillation process S6
of dry-distilling the mixture , and further includes, before the dry-distillation process S6
5 and after the mixing process S3 (between the mixing process S3 and the dry-distillation
process S6), the drying process S4 of drying the mixture such that the moisture of the
mixture is from 0% by mass to 8% by mass . Therefore, even when low-quality coal, in
which a large amount of non-caking coal or slightly caking coal is blended, is used as
raw coal, the crushed caking additive containing fine particles with a particle size of 0.3
10 mm or less can be uniformly dispersed in the raw coal and the bulk density of the mixture
of the crushed caking additive and the raw coal can be improved . Therefore,
high-strength coke z can be produced.
[0055]
In addition, the method of producing high - strength coke according to the present
15 invention further includes, before the dry-distillation process S6 and after the drying
process S4, the moisture adjustment process S5 of adding moisture such that the moisture
of the dry mix is equal to or greater than 6% by mass . Therefore , by using the raw coal
and the crushed caking additive containing the fine particles with a particle size of 0.3
mm or less, the high -strength coke z can be produced while preventing the fine particles
20 of the crushed caking additive from being dispersed as dust.
[0056]

In the above-described first embodiment, the case where the crushed caking
additive containing 50% by mass to 100% by mass of the fine particles with a particle
.25 size of U1 mm to 0.3 mm is mixed with the raw coal to obtain the mixture; and the
moisture of the mixture is adjusted in the range of 0% by mass to 8% by mass, has been
described. However, in this embodiment, a case where the crushed caking additive
containing 30% by mass to 100% by mass of the fine particles with a particle size of 0.01
mm to 0.3 mm is mixed with the raw coal to obtain the mixture; and the moisture of the
30 mixture is adjusted in the range of 0% by mass to 7% by mass, will be described.
[0057]
A method of producing high-strength coke according to this embodiment is the
same as that according to the first embodiment, except for the content of the fine particles
18
with a particle size of 0.01 mm to 0.3 mm included in the crushed caking additive and the
moisture of the mixture.
[0058]
The method of producing high-strength coke according to this embodiment
5 includes a crushing process of crushing the solid caking additive to obtain the crushed
caking additive containing 30% by mass to 100% by mass of the fine particles with a
particle size of 0.01 mm to 0.3 mm, the mixing process of mixing the crushed caking
additive and the raw coal to obtain the mixture, and the dry-distillation process of
dry-distilling the mixture, and further includes, before the dry-distillation process and
10 after the mixing process (between the mixing process and the dry-distillation process), a
drying process of drying the mixture such that the moisture of the mixture is from 0% by
mass to 7% by mass.
[0059]
In this embodiment, the content of the fine particles with a particle size of 0.01
15 mm to 0.3 mm included in the crushed caking additive is adjusted to be preferably equal
to or greater than 30% by mass in order to obtain coke having a sufficient strength.
However, in order to improve the coke strength fu ther, the content is adjusted to be
preferably equal to or greater than 40% by mass and more preferably equal to or greater
than 50% by mass.
20 [0060]
In addition, in this embodiment, the content of the fine particles with a particle
size of 0.01 mm to 0.3 mm included in the crushed caking additive is from 30% by mass
to 100% by mass. Therefore, when the moisture of the dry mix exceeds 7% by mass,
the quasi-particles with a particle size suitable for mixing with the raw coal cannot be
.25 formed and it is difficult to uniformly disperse the crushed caking additive in the raw
coal. As a result, the coke strength is insufficient.
[0061]
In order to more uniformly disperse the crushed caking additive in the raw coal,
it is preferable that the moisture of the dry mix be lower. Specifically, it is more
30 preferable that the moisture be less than or equal to 6.5% by mass.
In addition, the moisture of the dry mix may be 0% by mass. However, 6% by
mass or more is preferable in order to reduce the time required for drying the mixture,
perform the drying process efficiently, and prevent the dust dispersal from occurring
19
during transportation or when the dry mix is charged into a coke oven. When the
moisture of the dry mix is equal to or greater than 6% by mass, the dust dispersal can be
prevented sufficiently without performing the moisture adjustment process of adding
moisture such that the moisture of the dry mix is equal to or greater than 6% by mass,
5 before the dry-distillation process and after the drying process. Therefore, coke can be
produced efficiently as compared to a case where the moisture adjustment process is
performed.
[0062]
In this embodiment, the content of the fine particles with a particle size of 0.01
10 mm to 0.3 mm included in the crushed caking additive is from 30% by mass to 100% by
mass. However, by drying the mixture to obtain the dry mix with a moisture of 0% by
mass to 7% by mass, the crushed caking additive containing the fine particles with a
particle size of 0.3 min or less can be uniformly dispersed in the raw coal.
[0063]
15 Therefore, similarly to the above-described first embodiment, in the method of
producing high-strength coke according to this embodiment, even when low-quality coal,
in which a large amount of non-caking coal or slightly caking coal is blended, is used as
raw coal, the crushed caking additive containing fine particles with a particle size of 0.3
mm or less can be uniformly dispersed in the raw coal and the bulk density of the mixture
20 of the crushed caking additive and the raw coal can be improved. Therefore,
high-strength coke can be produced.
[0064]

FIG 2 is a flowchart illustrating a method of producing high-strength coke
-25 according to a third embodiment which is an example of a method of producing
high-strength coke according to the present invention. In the above-described first and
second embodiments, the drying process S4 is performed before the dry-distillation
process S6 and after the mixing process S3. However, as illustrated in FIG. 2, in the
method of producing high-strength coke according to the third embodiment, a drying
30 process S41 is performed before a mixing process S3 1.
[0065]
The method of producing high-strength coke according to this embodiment is
the same as that of the first or second embodiment, except that the drying process S41 is
20
performed before the mixing process S3 1.
That is, as illustrated in FIG 2, the method of producing high-strength coke
according to this embodiment includes the crushing process Si of crushing the solid
caking additive to obtain the crushed caking additive containing 50% by mass to 100%
5 by mass (or 30% by mass to 100% by mass) of the fine particles with a particle size of
0.01 mm to 0.3 mm, the raw coal crushing process S2, the mixing process S31 of mixing
the crushed caking additive and the raw coal to obtain the mixture, the moisture
adjustment process S5, and the dry-distillation process S6 of dry-distilling the mixture,
and further includes, before the mixing process S3 1, the drying process S41 of drying the
10 raw coal such that the moisture of the mixture of the mixing process is from 0% by mass
to 8% by mass (from 0% by mass to 7% by mass when the content of the fine particles
with a particle size of 0.01 mm to 0.3 mm included in the crushed caking additive is from
30% by mass to 100% by mass).
[0066]
15 The drying process S41 according to this embodiment is a process of drying the
crushed raw coal using a drying machine such that the moisture of the mixture of the
mixing process S31 is from 0% by mass to 8% by mass (from 0% by mass to 7% by
mass when the content of the fine particles with a particle size of 0.01 mm to 0.3 mm
included in the crushed caking additive is from 30% by mass to 100% by mass).
20 In the drying process S41, a target value in a range of the moisture of the raw
coal after performing the drying process S41 is calculated in advance and then the raw
coal is dried to be this target value. The target value of the moisture of the raw coal
after performing the drying process S41 can be calculated as follows. That is, by using
the moisture of the crushed caking additive and the content of the crushed caking
25 additive included in the mixture, the range of the moisture of the raw coal is determined
such that the moisture of the mixture of the mixing process is in the above-described
range.
[0067]
In addition, the moisture of the raw coal after performing the drying process S41
30 may be 0% by mass. However, the moisture of the mixture is equal to or greater than
6% by mass is preferable in order to reduce the time required for drying the raw coal,
perform the drying process S41 efficiently, and prevent the dust dispersal from occurring
during transportation or when the dry mix is charged into a coke oven.
21
When the moisture of the dry mix obtained by mixing the crushed caking
additive with the raw coal after performing the drying process S41 is equal to or greater
than 6% by mass, the dust dispersal can be prevented sufficiently without performing the
moisture adjustment process S5 of adding moisture such that the moisture of the dry mix
5 is equal to or greater than 6% by mass, before the dry-distillation process S6 and after the
drying process S41. Therefore, coke can be produced efficiently as compared to a case
where the moisture adjustment process S5 is performed.
[0068]
In the drying process S41, it is preferable to heat the raw coal. Accordingly,
10 the raw coal can be dried efficiently. A temperature of heating the raw coal is not
particularly limited. However, in the mixing process S31 which is performed after the
drying process S4 1, in order to prevent the solid caking additive from becoming liquid or
fused by contacting the raw coal, a temperature equal to lower than a softening point of
the solid caking additive is preferable.
15 [0069]
The mixing process S31 is a process of mixing the crushed caking additive as
the solid caking additive that is in the solid state and contains the fine particles with a
particle size of 0.3 mm or less which form quasi-particles after aggregation; and the raw
coal crushed in the raw coal crushing process S2 and dried in the drying process S41 to
20 obtain a mixture.
[0070]
In the method of producing high-strength coke according to the present
invention, in the crushing process S 1, the content of the fine particles with a particle size
of 0.01 mm to 0.3 mm included in the crushed caking additive is adjusted to be from
-25 50% by mass to 100% by mass (or 30% by mass to 100% by mass); in the drying process
S41, the moisture of the mixture of the mixing process S31 is adjusted to be from 0% by
mass to 8% by mass (from 0% by mass to 7% by mass when the content of the fine
particles with a particle size of 0.01 mm to 0.3 mm included in the crushed caking
additive is from 30% by mass to 100% by mass). Therefore, similarly to the
30 above-described first and second embodiments, even when low-quality coal, in which a
large amount of non-caking coal or slightly caking coal is blended, is used as raw coal,
the crushed caking additive containing fine particles with a particle size of 0.3 mm or less
can be uniformly dispersed in the raw coal and the bulk density of the mixture of the
22
crushed caking additive and the raw coal can be improved. Therefore, high-strength
coke can be produced.
[00711

5 FIG 3 is a flowchart illustrating a method of producing high-strength coke
according to a fourth embodiment which is an example of a method of producing
high-strength coke according to the present invention. In the above-described first and
second embodiments, the drying process S4 is performed before the dry-distillation
process S6 and after the mixing process S3. However, as illustrated in FIG. 3, in the
10 method of producing high-strength coke according to the third embodiment, a drying
process is performed in parallel with a mixing process S32.
[0072]
The method of producing high-strength coke according to this embodiment is
the same as those of the first and second embodiments, except that the drying process is
15 performed in parallel with the mixing process S32.
That is, as illustrated in FIG. 3, the method of producing high-strength coke
according to this embodiment includes the crushing process Si of crushing the solid
caking additive to obtain the crushed caking additive containing 50% by mass to 100%
by mass (or 30% by mass to 100% by mass) of the fine particles with a particle size of
20 0.01 mm to 0.3 mm 5, the raw coal crushing process S2, A mixing process S32 of mixing
the crushed caking additive and the raw coal to obtain the mixture, the moisture
adjustment process S5, and the dry-distillation process S6 of dry-distilling the mixture,
and further includes the drying process, which is performed in parallel with the mixing
process S32, of drying the crushed caking additive and the raw coal while being mixed
.25 with each other to form a mixture with a moisture of 0% by mass to 8% by mass (0% by
mass to 7% by mass when the content of the fine particles with a particle size of 0.01 mm
to 0.3 mm included in the crushed caking additive is from 30% by mass to 100% by
mass). Therefore, in this embodiment, the mixing process S32 also serves as the drying
process.
30 [0073]
The drying process (mixing process S32) of this embodiment is a process of
drying the crushed caking additive and the raw coal while being mixed with each other to
form the mixture with a moisture of 0% by mass to 8% by mass (0% by mass to 7% by
23
mass when the content of the fine particles with a particle size of 0.01 mm to 0.3 mm
included in the crushed caking additive is from 30% by mass to 100% by mass).
[0074]
In the method of producing high-strength coke according to the present
5 invention, in the crushing process S 1, the content of the fine particles with a particle size
of 0.01 mm to 0.3 mm included in the crushed caking additive is adjusted to be from
50% by mass to 100% by mass (or 30% by mass to 100% by mass); in the drying process
(mixing process S32), the crushed caking additive and the raw coal are dried while being
mixed with each other to form the mixture with a moisture of 0% by mass to 8% by mass
10 (0% by mass to 7% by mass when the content of the fine particles with a particle size of
0.01 mm to 0.3 mm included in the crushed caking additive is from 30% by mass to
100% by mass). Therefore, similarly to the above-described first and second
embodiments, even when low-quality coal in which a large amount of non-caking coal or
slightly caking coal is blended is used as raw coal, the crushed caking additive containing
15 fine particles with a particle size of 0.3 mm or less can be uniformly dispersed in the raw
coal and the bulk density of the mixture of the crushed caking additive and the raw coal
can be improved. Therefore, high-strength coke can be produced.
Examples
20 [0075]
Next, Examples of the present invention will be described. The conditions of
Examples are merely employed as examples for examining the operability and effect of
the present invention, and the present invention is not limited these examples. The
present invention can employ various conditions in order to achieve the object of the
-25 invention without departing from the scope of the invention.
[0076]
(Examples)
Petroleum-based solid caking additives with total sulfur contents (T S) as shown
in Table 2 and softening points as shown in Tables 3 to 7 were crushed to obtain crushed
30 caking additives containing fine particles with a particle size of 0.01 mm to 0.3 mm and
particles with a particle size of 3 mm or less with contents shown in Tables 3 to 7
(crushing process).
In addition, raw coals with the blending ratios shown in Tables 3 to 7 were
24
prepared as the raw coal. Among the raw coals shown in Tables 3 to 7, a part of the raw
coals were crushed to match percentages of the particles with a particle size of 3 mm or
less and percentages of the fine particles with a particle size of 0.01 mm to 0.3 mm which
are shown in Tables 3 to 7 (raw coal crushing process).
5 [0077]
[Table 2]
[0078]
[Table 3]
10
[0079]
[Table 4]
[0080]
15 [Table 5]
[00811
[Table 6]
20 [0082]
[Table 7]
[0083]
Next, the raw coals of Examples 5-1 to 5-5 and Comparative Examples 5-1 to
25 5-5 were put into a drying machine and dried (drying process). Then, the dried raw
coals and the crushed caking additives shown in Table 5 were mixed with ratios shown in
Table 5 to obtain mixtures (mixing process) with moisture shown in Table 5.
Next, moisture was added to the mixtures of Examples 5-1 to 5-5 and
Comparative Examples 5-1 to 5-5 (moisture adjustment process) to obtain mixtures with
30 moisture shown in Table 5. Then, the mixtures thus obtained were dry-distilled in a
coke oven to obtain cokes of Examples 5-1 to 5-5 and Comparative Examples 5-1 to 5-5
(dry-distillation process).
[0084]
25
In addition, raw coals of Examples 6-1 to 6-5, Examples 7-1 to 7-5,
Comparative Examples 6-1 to 6-5, and Comparative Examples 7-1 to 7-5 and crushed
caking additives shown in Tables 6 and 7 were put into a drying machine with ratios
shown in Tables 6 and 7 and dried while being mixed with each other to obtain mixtures
5 with moisture shown in Tables 6 and 7 (mixing process and drying process).
Next, moisture was added only to the mixtures of Examples 6-1 to 6-5 and
Comparative Examples 6-1 to 6-5 (moisture adjustment process) to obtain mixtures with
moisture shown in Table 6. Then, the mixtures thus obtained were dry-distilled in a
coke oven to obtain cokes of Examples 6-1 to 6-5, Examples 7-1 to 7-5, Comparative
10 Examples 6-1 to 6-5, and Comparative Examples 7-1 to 7-5 (dry-distillation process).
[0085]
In addition, raw coals of Examples 1-1 to 1-18 and 2-1 to 2-6 and Comparative
Examples 1-1 to 1-5, 2-1 to 2-3, and 3-1 to 3-9 and crushed caking additives shown in
Tables 3 and 4 were mixed with ratios shown in Tables 3 and 4 to obtain mixtures
15 (mixing process). Then, the mixtures were put into a drying machine and dried to
obtain mixtures with moisture shown in Tables 3 and 4 (drying process).
Next, moisture was added to the mixtures of Examples 1-1 to 1-18 and 2-1 to
2-6 and Comparative Examples 1-1 to 1-5, 2-1 to 2-3, and 3-1 to 3-9 (moisture
adjustment process) to obtain mixtures with moisture shown in Tables 3 and 4. Then,
20 the mixtures thus obtained were dry-distilled in a coke oven to obtain cokes of Examples
1-1 to 1-18 and 2-1 to 2-6 and Comparative Examples 1-1 to 1-5, 2-1 to 2-3, and 3-1 to
3-9 (dry-distillation process).
[0086]
In addition, raw coals of Comparative Examples 4-1 to 4-5 and crushed caking
.25 additives-shown in Table 4 were mixed with ratios shown in Table 4 to obtain mixtures
with moisture shown in Table 4.
Next, the mixtures thus obtained were dry-distilled in a coke oven to obtain
cokes of Comparative Examples 4-1 to 4-5.
[0087]
30 All the coke strengths of the obtained cokes of Examples and Comparative
Examples were measured. Here, DI(15) was measured as the index of the coke strength.
These measurement results are shown in Tables 3 to 6 and FIG. 4.
As shown in Tables 3 to 6, all the coke strengths of Examples were improved
26
significantly more than those of Comparative Examples.
[0088]
FIG. 4 is a graph illustrating the relationship between a strength (DI(15)), a
moisture of a mixture, and a content of fine particles with a particle size of 0.01 mm to
5 0.3 mm which were included in a crushed caking additive with regard to the cokes of
Examples 1-1 to 1-18 and 2-1 to 2-6, and Comparative Examples 1-1 to 1-5, 2-1 to 2-3,
3-1 to 3-9, and 4-1 to 4-5.
As illustrated in Fig. 4, when the crushed caking additive containing 50% by
mass or more the fine particles with a particle size of 0.01 mm to 0.3 mm and the raw
10 coal were mixed to obtain the mixture with the moisture of 8% by mass or less, and when
the crushed caking additive containing 30% by mass or more of the fine particles with a
particle size of 0.01 mm to 0.3 mm and the raw coal were mixed to obtain the mixture
with the moisture of 7% by mass or less. In these cases, it was found that the coke
strength equal to or greater than 85 (DI(15)) could be secured.
15 [0089]
In addition, particle emission times, which are the period of duration of the
particle emission occurring when the mixtures were charged into the coke oven in order
to obtain all the cokes of Examples and Comparative Examples, were measured. The
measurement results thereof are shown in Table 3 to 6 and FIG 5.
20 As shown in Tables 3 to 6, all the particle emission times of Examples were
equal to or shorter than 16 seconds. On the other hand, the particle emission times of
Comparative Examples 3-1 to 3-9 exceeded 16 seconds.
[0090]
FIG 5 is a graph illustrating the relationship between the particle emission times
=25 and the moisture of the mixtures of Examples 1-1 to 1-18 and 2-1 to 2-6, and
Comparative Examples 1-1 to 1-5, 2-1 to 2-3, 3-1 to 3-9, and 4-1 to 4-5. Here, in FIG 5,
a horizontal dotted line represents a position where the particle emission time is 16
seconds, and a vertical dotted line represents a position where the moisture is 6%.
As illustrated in FIG 5, as the moisture of the mixture becomes lower, the
30 particle emission phenomenon lasts for a longer time, and as the moisture of the mixture
increases, the particle emission phenomenon lasts for a shorter time. Specifically, it was
found that, when the moisture of the mixture is equal to or greater than 6% by mass, the
particle emission time is equal to or shorter than 16 seconds. In addition, it can be
27
found that, when the moisture in the coal charge is less than 6% by mass, the particle
emission time is significantly increased.
Industrial Applicability
5 [0091]
As described above, according to the present invention, even when the used
percentage of the low-quality raw coal (non-caking coal or slightly caking coal) is
increased, coke having a higher strength than that in the related art can be produced at a
low cost. Therefore, the present invention has a high applicability in the coke
10 production industry.
Reference Signs List
[0092]
Si crushing process
15 S2 raw coal crushing process
S3, S31, S32 mixing process
S4, S41 drying process
S5 moisture adjustment process
S6 dry-distillation process
20 x raw coal
y solid caking additive
z coke
T1 klo
Granularity (%)
not not not not not not
less less less less less less
than than than than than than
0.25 mm 0.197 mm 0.149 mm 0.105 mm 0.074 mm 0.063 mm
2.9 5.3 1 4.8 9.2 18.2 25.1
not
less
than
0.052 mm
7
0.052 mm
or less
27.5
Moisture
(%)
1.09
Humidity-
Controlled
Moisture
(%)
5.3
Kinds of Solid Caking Additives
Table 3 (1/3)
24
Comparative Exam le 1-1 34
Comparative Exam le 1-2 34
Comparative Exam le 1-3 34
Comparative Exam le 1-4 34
Comparative Example 1-5 34
Example 1-1
Example 1-2
Example 1-3
Example 1-4
Example 1-5
Example 1-6
Example 1-7
Example 1-8
Example 1-9
Example 2-5 4
Example 1-10
Example 1-11
Example 1-12
Example 1-16
Example 1-17
Example 1-18
34
34
Example 1-13 34
Example 1-14 34
Example 1-15 34
Comparative Exam le 2-1 41
Comparative Example 2-2 41
Comparative Exam le 2-3 41
Example 2-1 41
Exam le 2-2 41
Exam le 2-3 41
Example 2-4 41
Example 2-6 { 41
Strongly Caking Strongly Caking Strongly Caking Percentage of Percentage of Particle Size
Non-Caking Coal Slightly Caking Coal Particle Size of 0 01 Coal A Coal B Coal C .
of 3 mm or less
mm to 0.3 mm
ILI (% by mass) (% by weight)
5 24
5 24
5 24
5 24
34
34 { 5
34 5
34
34
34 5
34
5
5
5
5
5
5
5
5
5
5
5
5
24
24
24
24
Blending Ratio of Raw Coal
10
10
10
10
10
10
10
10
10
10
24 10
24 10
24
24
10
10
24 10
24 10
24 10
24 10
24 10
24
24
24
24
10
10
10
10
24 10
24 10
24 10
24 10
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
27
20
20
20
22 79
24 81
29 83
25 82
24 81
23 83
25 83
26 84
25 82
27 83
24 81
22 79
20 77
22 76
24 77
22 76
26
29 82
23 77
22 78
21 77
22
26 80
22 78
21 77
22 77
25 81
22 78
21 77
21 77
24 10
24 { 10
24 10 22 79
Table 3 (2/3)
Comparative Exam le 1-1
Comparative Exam le 1-2
Comparative Example 1-3
Comparative Exam le 1-4
Comparative Exam le 1-5
Example 1-1
Example 1-2
Example 1-3
Example 1-4
Example 1-5
Example 1-6
Example 1-7
Example 1-8
Example 1-9
Example 1-10
Example 1-11
Example 1-12
Example 1-13
Example 1-14
Example 1-15
Example 1-16
Example 1-17
Example 1-18
Petroleum-Based A
Petroleum-Based A
Petroleum-Based A
Petroleum-Based A
Petroleum-Based A
Petroleum-Based A
Moisture Before
Moisture Adjustment
Process
(%)
5.5
5.8
5.9
5.9
5.5
5.5
5.5
5.8
5.7
5.5
5.8
5.5
5.7
5.7
5.6
5.9
5.8
5.9
5.5
5.2
5.6
5.5
5.5
Moisture After
Moisture Adjustment
Process
(%)
6.0
6.3
6.6
6.6
7.0
6.0
6.5
6.3
6.7
7.0
6.8
6.0
6.2
6.2
6.1
6.4
6.8
6.9
7.0
6.2
6.6
7.0
7.0
Percentage of Particle
Size of 0.01 mm to 0.3
mm
b mass)
5
5
5
5
5
30
30
30
30
30
30
30
30
40
40
40
Table 3 (3/3)
Drying Temperature
Comparative Example 1-1 170
Comparative Exam le 1-2 170
Comparative Exam le 1-3 170
Comparative Example 1-4 170
Comparative Example 1-5 170
Example 1-1 170
Example 1-2 170
Example 1-3 170
Example 1-4 170
Example 1-5 170
Example 1-6 170
Example 1-7 170
Example 1-8 170
Example 1-9
Example 1-10
Example 1-11
Example 1-12
Example 1-13
Example 1-14
Example 1-15
Example 1-16
Example 1-17
Example 1-18
Comparative Example 2-1
Comparative Example 2-2
Comparative Example 2-3
Example 2-1
170
170
170
170
170
170
170
170
170
170
130
130
130
130
Example 2-2 130
Example 2-3 130
Exam le 2-4 13 1711
2-5 130
Example 2-6 130
Coke Strength
DI(15)
84.8
84.8
84.8
84.6
84.5
85.5
85.1
85.3
85.2
85.0
85.0
85.6
85.4
86.0
85.7
85.6
85.4
85.3
85.5
86.2
86.1
86.4
85.9
84.9
84.9
84.9
85.9
85.6
85.3
85.5
85.4
85.3
Particle Emission Time when being charged
(s)
13
10
8
7
12
12
10
12
9
12
12
15
9
9
4
8
9
Table 4 (1/3)
Comparative
Example 3-1
Comparative
Example 3-2
Comparative
Example 3-3
Comparative
Example 3-4
Comparative
Example 3-5
Comparative
Example 3-6
Comparative
Example 3-7
Comparative
Example 3-8
Comparative
Example 3-9
Comparative
Example 4-1
Comparative
Example 4-2
Comparative
Example 4-3
Comparative
Example 4-4
Comparative
Example 4-5
41
5 24
5 24
5
5
5
5
5
5
5
5
5
5
5
24
24
24
24
24
24
24
24
24
24
24
Percentage of Particle
Non-Caking Coal Slightly Caking Coal I Size of 0.01 mm to
0.3 mm
(%) I (% by mass)
10
10
10
10
10
10
10
10
10
10
10
10
10
30
30
30
30
30
30
30
20
30
20
20
20
28
27
22
29
27
20
21
22
25
24
26
24
20 23 79
Strongly Caking Coal Strongly Caking Coal Strongly Caking Coal
A B C
Comparative
Example 4-2
Comparative
Example 4-5
Blending Ratio
Kinds
Softening Point
Petroleum-Based B ! 140
Solid Caking Additive
Moisture Before Moisture After Percentage of Particle
Moisture Adjustment Moisture Adjustment Size of 0.01 mm to
Process Process 0.3 mm
(%) (%) (% by mass)
Percentage of Particle Size of 3
nun or less
% by weight
Table 4 (3/3)
Drying Temperature
(°C)
Coke Strength
DI(15)
Particle Emission Time when being charged
(s)
Comparative Example 3-1 170 84.9 24
Comparative Example 3-2 170 84.7 23
Comparative Example 3-3 170 84.6 20
Comparative Example 3-4 170 84.4 25
Comparative Example 3-5 170 84.6 18
Comparative Example 3-6 170 84.9 17
Comparative Example 3-7 170 84.9 22
`,.3
Comparative Example 3-8 170 84.4 1 18
Comparative Example 3-9 170 84.6 1 26
Comparative Example 4-1 84.7 5
Comparative Example 4-2 I 84.6 4
Comparative Example 4-3 84.4 8
Comparative Example 4-4 84.8 4
Comparative Example 4-5 84.6 9
Table 5 (1/3)
Blending Ratio of Raw Coal
Strongly Caking Coal Strongly Caking Coal Strongly Caking Coal
A B C
(%)
34 5 24
34
34
34
34
5
5
5
5
5
5
5
5
5
Non-Caking Coal Slightly Caking Coal
(%)
10 27
Percentage of Particle
Percentage of Particle
Size of 0.01 mm to 0.3
mm
Size of 3 mm or less
(% by mass) (% by weight)
21 77
24 10 27 27 81
24 10 27 27 28
24 10 27 24 77
24 10 27 25 79
24 10 27 22 77
24 10 27 20 76
24 10 27 24 80
24 10 27 27 79
Table 5 (2/3)
Solid Caking Additive
Blending Ratio
Kinds
Softening Point
(°C)
Moisture Before
Moisture Adjustment
Process
(%)
Moisture After
Moisture Adjustment
Process
(%)
Percentage of Particle
Size of 0.01 mm to 0.3
mm
(% by mass)
Percentage of
Particle Size of 3
mm or less
(% by weight)
Comparative Example
5-1
7 Petroleum-Based A 180 5.5 7.0 5 19
Comparative Example
5-2
Petroleum-Based A 180 5.7 7.2 5 20
Comparative Example
5-3
2 Petroleum-Based A 180 5.8 7.3 5 20
Comparative Example
5-4
2 Petroleum-Based A 180 5.7 7.2 5 20
Comparative Example
5-5
2 Petroleum-Based A 180 5.6 7.1 5 21
Example 5-1 2 Petroleum-Based A 180 5.8 7.3 50 89
Example 5-2 2 Petroleum-Based A 180 5.5 7.0 50 91
Example 5-3 2 Petroleum-Based A 180 5.7 7.2 50 90
Example 5-4 2 Petroleum-Based A 180 5.7 7.2 50 92
Example 5-5 2 Petroleum-Based A 180 5.6 7.1 50 91
Table 5 (3/3)
Drying Temperature
(°C)
Coke Strength
DI(15)
Particle Emission Time when being charged
(s)
Comparative Example
5-1
170 84.7 12
Comparative Example
5-2 170 84.8 9
Comparative Example
5-3
170 N 84.8 14
Comparative Example
5-4
170 84.9 15
Comparative Example
5-5
170 84.7 12
Example 5-1 170 85.2 13
Example 5-2 170 N 85.3 11
Example 5-3 170 85.4 14
Example 5-4 1 170 85.4 1 14
Example 5-5 1 170 85.4 12
Table 6 (1/3)
A B I C
(%) (ON
27
27
27
27
27
27
27
27
27
Example 6-5 34 A 5 1 24 1 10 27
Blending_Ratio of Raw Coal
Strongly Caking Coal Strongly Caking Coal Strongly Caking Coal
Non-Caking Coal Slightly Caking Coal
Percentage of Particle
Size of 0.01 mm to 0.3
mm
(% by mass)
24
28
27
29
25
20
21
22
27
26
Percentage of Particle
Size of 3 mm or less
% by weight)
79
83
82
79
78
79
Table 6 (2/3)
Comparative Example
6-1
Comparative Example
6-2
Comparative Example
6-3
Comparative Example
6-4
Comparative Example
6-5
Blending Ratio
(ON
Kinds
Softening Point
CC)
Process (%) Process (%) 0.3 mm
2 Petroleum-Based A 180 5.9 7.4
2 Petroleum-Based A w 180
2 Petroleum-Based A 180
2 Petroleum-Based A 180
5.8
5.5
7.4
7.3
7.0
2 1 Petroleum-Based A 180 1 5.5 1 7.0
Example 6-1 2 1 Petroleum-Based A 1 180 5.7 N 7.2
Example 6-2 2 1 Petroleum-Based A N 180 5.6 7.1
Example 6-3 2 1 Petroleum-Based A 1 180 5.9 7.4
Example 6-4 2 Petroleum-Based A 180 5.9 7.4
Example 6-5 2 1 Petroleum-Based A 1 180 1 5.7 1 7.2
Solid Caking Additive
Moisture Before Moisture After Percentage of Particle Percentage of Particle Size
Moisture Adjustment Moisture Adjustment Size of 0.01 mm to
J J of 3 mm or less
5.9
by mass) % b weight)
5 22
5 9 20
5 1 19
5 22
5 21
Table 6 (3/3)
Drying Temperature N Coke Strength Particle Emission Time when being charged
(°C) I DI(15) (s)
Comparative Example
6-1 170 1 84.6 14
Comparative Example
6-2 170 84.5 12
Comparative Example
6-3 170 84.8 13
Comparative Example
6-4 170 84.9 14
Comparative Example
6-5 170 84.8 15
Example 6-1 170 85.2 13
Example 6-2 170 85.2 10
Example 6-3 170 85.0 12
Example 6-4 170 85.1 12
Example 6-5 170 I 85.1 10
Table 7 (1/3)
Comparative Example
7-2
Strongly Caking Coal Strongly Caking Coal
B C
(%)
27
27
27
Percentage of Particle
Size of 0.01 mm to 0.3
mm
(% by mass)
22
24
26
el. b weight)
77
83
82
84
80
78
75
77
81
80
Comparative Example
7-1
Comparative Example
7-2
140 7.7 - 5 20
140 1 7.8 - 5 22
Example 7-3 2 Petroleum-Based A 1 140 7.7 - 50
Example 7-4 2 Petroleum-Based A 140
Example 7-5 1 2 1 Petroleum-Based A 1 140
Solid Caking Additive
Moisture Before Blending Ratio Moisture After
Kinds
Softening Point
Moisture Adjustment Moisture Adjustment
%) aC Process (%) Process (%)
2 1 Petroleum-Based A 1 140 6.9
Percentage of Particle
Percentage of Particle
Size of 0.01 mm to 0.3
Size of 3 mm or less
mm
by mass) (% by weight)
Petroleum-Based A l 140 1 7.8 - 5 19
Table 7 (3/3)
Drying Temperature
(°C)
Coke Strength
DI(15)
Particle Emission Time when being charged
(s)
Comparative Example
7-1 130 84.5 15
Comparative Example
7-2 130 84.9 12
Comparative Example
7-3 130 84.7 14
Comparative Example
7-4 130 84.9 14
Comparative Example
7-5 130 84.8 14
Example 7-1 130 85.4 13
Example 7-2 130 85.3 15
Example 7-3 130 85.0 13
Example 7-4 1 130 85.2 12
Example 7-5 ! 130 85.2 11

We claim:
1. A method of producing high-strength coke comprising:
a crushing process of crushing a solid caking additive to form a crushed caking
additive containing 50% by mass to 100% by mass of fine particles with a particle size of
5 0.01 mmto0.3mm;
a mixing process of mixing the crushed caking additive and raw coal with each
other to prepare a mixture;
a dry-distillation process of dry-distilling the mixture; and
a drying process which is performed before the mixing process, in parallel with
10 the mixing process, or before the dry-distillation process and after the mixing process,
wherein when the drying process is performed before the mixing process, the
raw coal is dried to adjust the moisture of the mixture of the mixing process in a range of
0% by mass to 8% by mass in the drying process,
when the drying process is performed in parallel with the mixing process, the
15 crushed caking additive and the raw coal are dried while being mixed to form a mixture
with a moisture of 0% by mass to 8% by mass in the drying process, and
when the drying process is performed before the dry-distillation process and
after the mixing process, the mixture is dried to adjust the moisture of the mixture in a
range of 0% by mass to 8% by mass in the drying process.
20
2. A method of producing high-strength coke comprising:
a crushing process of crushing a solid caking additive to form a crushed caking
additive containing 30% by mass to 100% by mass fine particles with a particle size of
0.01 mm to 0.3 mm;
-25 a mixing process of mixing the crushed caking additive and raw coal with each
other to prepare a mixture;
a dry-distillation process of dry-distilling the mixture; and
a drying process which is performed before the mixing process, in parallel with
the mixing process, or before the dry-distillation process and after the mixing process,
30 wherein when the drying process is performed before the mixing process, the
raw coal is dried to adjust the moisture of the mixture of the mixing process in a range of
0% by mass to 7% by mass in the drying process,
when the drying process is performed in parallel with the mixing process, the
V'_
e9l
crushed caking additive and the raw coal are dried while being mixed with each other to
form a mixture with a moisture of 0% by mass to 7% by mass in the drying process, and
when the drying process is performed before the dry-distillation process and
after the mixing process, the mixture is dried to adjust the moisture of the mixture in a
5 range of 0% by mass to 7% by mass in the drying process.
3. The method of producing high-strength coke as claimed in Claim 1 or 2,
further comprising,
a moisture adjustment process of adding moisture such that a moisture of the
10 mixture is equal to or greater than 6% by mass before the dry-distillation process and
after the drying process.
4. The method of producing high-strength coke as claimed in Claim 1 or 2,
wherein, in the crushing process, a crushed caking additive containing 80% by
15 mass or more of particles with a particle size of 3 mm or less is formed.
5. The method of producing high-strength coke as claimed in Claim 1 or 2,
wherein the raw coal contains 20% by mass to 60% by mass of one or both of
20 slightly caking coal and non-caking coal.
6. The method of producing high-strength coke as claimed in Claim 1 or 2,
wherein, in the drying. process, the mixture is heated at a temperature equal to or
lower than a softening point of the solid caking additive.