TECHNICAL FIELD
The present invention relates to a coal pyrolizing device.
5 BACKGROUND ART
Since low-rank coal (low-quality coal) containing a large
amount of water such as brown coal and subbituminous coal has a
low heating value per unit weight, the low-rank coal is heated
to be dried and pyrolized and is also upgraded in a low oxygen
10 atmosphere to reduce surface activity. The low-rank coal is
thereby turned into upgraded coal which has an improved heating
value per unit weight while being prevented from spontaneously
combusting.
For example, a rotary kiln-type coal pyrolizing device as
15 follows is known as a coal pyrolizing device configured to pyrolize
the dry coal produced by drying the low-rank coal. An inner tube
(cylinder main body) is rotatably supported inside a fixedly-held
outer tube (jacket) . Heating gas is supplied to an inside of the
outer tube (a space between the outer tube and the inner tube)
20 and the dry coal is supplied into the inner tube from one end side
thereof. The dry coal is then heated and pyrolized while being
agitated and moved from the one end side to the other end side
of the inner tube by rotating the inner tube. Then, the pyrolized
coal and the pyrolysis gas are sent out from the other end side
25 of the inner tube.
PRIOR ART DOCUMENT
PATENT DOCUMENT
Patent Document 1: Japanese Patent Application Publication
30 No. 2003-176985
Patent Document 2: Japanese Patent Application Publication
No. 2004-003738
Patent Document 3: Japanese Patent Application Publication No.
Hei 10-230137
5
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
When the dry coal is pyrolized, pyrolysis gas (thermal
decomposition gas) is generated which contains not only carbon
10 monoxide, water vapor, and tar but also a small amount of
mercury-based substances such as HgS and HgCl2 contained in the
dry coal.
Moreover, in the aforementioned rotary kiln-type coal
pyrolizing device, although a high temperature can be maintained
15 in a portion (center portion in an axial direction) of the inside
of the inner tube which is covered with the outer tube and which
is heated by the heating gas, drop of the temperature occurs in
a portion (portion on the other end side in the axial direction)
which protrudes from the outer tube without being covered with
20 the outer tube and which is not heated by the heating gas.
Accordingly, when the pyrolized coal and the pyrolysis gas
in the inner tube of the coal pyrolizing device move inside the
inner tube to the other end side thereof, the temperature of the
pyrolized coal and the pyrolysis gas drops. As a result, the
25 mercury-based substances in the pyrolysis gas are
physically-adsorbed onto the pyrolized coal, and the mercury
concentration in the pyrolized coal sent out from the other end
side of the inner tube increases. Meanwhile, when the temperature
of the pyrolized coal is high, the mercury-based substances in
30 the pyrolysis gas are chemically-adsorbed onto the pyrolized coal,
3
and the mercury concentration in the pyrolized coal sent out from
the other end side of the inner tube increases.
In view of this, an object of the present invention is to
provide a coal pyrolizing device capable of suppressing an
5 increase of mercury concentration in produced pyrolized coal.
MEANS FOR SOLVING THE PROBLEMS
A coal pyrolizing device according to a first aspect of the.
invention for solving the problems described above is a rotary
10 kiln-type coal pyrolizing device characterized in that an inner
tube is rotatably supported inside an outer tube, heating gas is
supplied into the outer tube, coal is supplied into the inner tube
from one end side of the inner tube and is heated and pyrolized
while being agitated and moved from the one end side to another
15 end side of the inner tube by rotating the inner tube, pyrolized
coal and pyrolysis gas are sent out from the other end side of
the inner tube, and the coal pyrolizing device comprises:
pyrolized coal discharging means, provided to be connected to the
other end side of the inner tube, for discharging the pyrolized
20 coal; gas discharging means, provided to be connected to the
pyrolized coal discharging means, for discharging the pyrolysis
gas; and gas flow-velocity regulating means, provided in the
pyrolized coal discharging means, for regulating a flow velocity
of the pyrolysis gas discharged to the gas discharging means.
25 A coal pyrolizing device of a second aspect of the invention
for solving the problems described above is the coal pyrolizing
device of the first aspect of the invention, characterized in that
the pyrolized coal discharging means is a chute, and the gas
flow-velocity regulating means includes a partition plate which
30 partitions a space inside the chute into a portion on the inner
tube side and a portion on the gas discharging means side while
4
allowing the pyrolysis gas to be discharged to the gas discharging
means side and which is capable of adjusting a size of a horizontal
cross section of the portion on the gas discharging means side
in the space inside'the chute.
5 A coal pyrolizing device of a third aspect of the invention
for solving the problems described above is the coal pyrolizing
device of the second aspect of the invention, characterized in
that the partition plate is formed of two plate bodies which are
provided on an output shaft of a motor and whose front end portion
10 sides are swingable in a horizontal direction by an actuation the
motor.
A coal pyrolizing device of a fourth aspect of the invention
for solving the problems described above is the coal pyrolizing
device of the second aspect of the invention, characterized in
15 that the partition plate is formed of a plate body which is provided
on a cylinder rod of a drive cylinder and which is capable of
advancing toward and retreating from the inner tube by an actuation
the drive cylinder.
A coal pyrolizing device of a fifth aspect of the invention
20 for solving the problems described above is the coal pyrolizing
device of the second aspect of the invention, characterized in
that the partition plate is formed of a plate body which is provided
on an output shaft of a motor and which has at least one end portion
side swingable relative to the inner tube by an actuation the motor.'
25 A coal pyrolizing device of a sixth aspect of the invention
for solving the problems described above is the coal pyrolizing
device of the fifth aspect of the invention, characterized in that
the coal pyrolizing device comprises a plurality of sets of the
plate bodies.
30 A coal pyrolizing device of a seventh aspect of the invention
for solving the problems described above is the coal pyrolizing
device of the first aspect of the invention, characterized in that
the coal pyrolizing device further comprises: gas state detecting
means capable of detecting the gas flow velocity of the pyrolysis'
gas discharged by the gas discharging means; and control means
5 for controlling the gas flow-velocity regulating means on the
basis of the gas flow velocity detected by the gas state detecting
means.
A coal pyrolizing device of an eighth aspect of the invention
for solving the problems described above is the coal pyrolizing
10 device of the second aspect of the invention, characterized in
that the gas flow-velocity regulating means includes centrifuging
means for separating the pyrolized coal from the pyrolysis gas
by centrif ugation, and the partition plate is a plate body provided
in a feed pipe configured to feed the pyrolysis gas and the
15 pyrolized coal from the pyrolysis discharging means to the
centrifuging means.
EFFECT OF THE INVENTION
In the coal pyrolizing device of the present invention, the
20 following can be achieved. When the temperature of the pyrolized
coal drops in a portion not heated by the heating gas, most of
mercury-based substances in the pyrolysis gas are
physically-adsorbed onto fine pyrolized coal in the pyrolized coal
because the particle diameter of the fine pyrolized coal is far
25 smaller than an average particle diameter and the specific surface
area per unit weight of the fine pyrolized coal is far greater
than that of the pyrolized coal of the average particle diameter..
Moreover, even if no physical adsorption occurs, the mercury-based
substances in the pyrolysis gas are chemically-adsorbed onto the
30 fine pyrolized coal in the pyrolized coal when the temperature
of the pyrolized coal exceeds the limit temperature of chemical
6
adsorption. However, by regulating the gas flow velocity of the
pyrolysis gas discharged from the gas discharging means with the
gas flow-velocity regulating means, it is possible to entrain,
in the pyrolysis gas, fine particles whose particle diameter is
5 far smaller than the average particle diameter of the pyrolized
coal, and separate the fine pyrolized coal from the pyrolized coal v
Hence an increase of mercury concentration in the produced
pyrolized coal can be suppressed.
10 BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic configuration diagram of a first
embodiment of a coal pyrolizing device in the present invention,
Fig. 1A shows a main portion thereof, and Fig. IB shows a view
in a direction of the arrow I in Fig. 1.
15 [Fig. 2] Fig. 2 is a graph showing a relationship between a
terminal velocity of pyrolysis gas in a chute of the coal pyrolizing
device and a particle diameter of coal conveyed by the pyrolysis
gas.
Fig. 3 is a graph showing particle size distribution of
20 pyrolized coal produced by the coal pyrolizing device.
Fig. 4 is a graph showing a relationship between a gas flow
velocity in a chamber (chute) of the coal pyrolizing device and
the cross-sectional -area of the chamber (chute) .
Fig. 5 is a schematic configuration diagram of a second
25 embodiment of the coal pyrolizing device in the present invention,
Fig. 5A shows a main portion thereof, and Fig. 5B shows a view
in a direction of the arrow V in Fig. 5.
Fig. 6 is a schematic configuration diagram of a third
embodiment of the coal pyrolizing device in the present invention,
30 Fig. 6A shows a main portion thereof, and Fig. 6B shows a view
in a direction of the arrow VI in Fig. 3.
7
Fig. 7 is a schematic configuration diagram of a fourth
embodiment of the coal pyrolizing device in the present invention,
Fig. 7A shows a main portion thereof, and Fig. 7B shows a view
in a direction of the arrow VII in Fig. 7.
5 Fig. 8 is a schematic configuration diagram of a fifth
embodiment of the coal pyrolizing device in the present invention.
Fig. 9 is a schematic configuration diagram of a sixth
embodiment of the coal pyrolizing device in the present invention,
Fig. 9A shows a main portion thereof, and Fig. 9B shows a view
10 in a direction of the arrow IX in Fig. 9.
Fig. 10 is a graph showing a relationship between an entrance
flow velocity into a centrifuge included in the coal pyrolizing
device and a collection limit particle diameter.
Fig. 11 is a graph showing a relationship between a flow
15 velocity at an entrance of the centrifuge and a cross-sectional
area of the entrance.
MODE FOR CARRYING OUT THE INVENTION
Embodiments of a coal pyrolizing device of the present
20 invention are described based on the drawings. However, the
present invention is not limited to the embodiments described
below based on the drawings.
FIRST EMBODIMENT
25 A first embodiment of the coal pyrolizing device of the
present invention is described based on Figs. 1A, IB, 2, 3, and
4.
As shown in Fig. 1A, a coal pyrolizing device 100 for
pyrolizing dry coal 1 produced by drying low-rank coal
30 (low-quality coal) which is coal containing a large amount of
moisture such as brown coal and subbituminous coal includes: a
8
hopper 101 which receives the dry coal 1 from a dry coal conveying
line 105 configured to convey the dry coal 1; a rotatably-supported
inner tube (cylinder main body) 102 into which the dry coal 1 in
the hopper 101 is supplied from one end side (base end side); an
5 outer tube (jacket) 103 which is fixedly supported to cover an
outer peripheral surface of the inner tube 102 while allowing the
inner tube 102 to rotate and which is configured such that heating
gas 11 being a heating medium is supplied to an inside of the outer
tube 103 (space between the outer tube 103 and the inner tube 102) ;
10 and a chute (chamber) 104 which is connected to the other end side
(front end side) of the inner tube 102 to allow the inner tube
102 to rotate and which sends out pyrolized coal 2 by causing the
pyrolized coal 2 to fall from the other end side (front end side)
of the inner tube 102. Note that a side wall 104b of the chute
15 104 is formed in an arc shape in a horizontal cross section.
One end side (base end side) of an exhaust line 106 for
discharging pyrolysis gas (heat decomposition gas) 12 such as
carbon monoxide, water vapor, and tar as well as fine pyrolized
coal 2a entrained in the pyrolysis gas 12 is connected to a top
20 plate 104a which is an upper portion of the chute 104 of the coal
pyrolizing device 100. The other end side (front end side) of the
exhaust line 106 is connected to a combustion furnace (not
illustrated) into which air and a combustion aid are supplied.
A heating gas feed line 107 whose base end side is connected
25 to the combustion furnace and which feeds the heating gas 11
generated by combusting the air and the combustion aid in the
combustion furnace is connected to the inside of the outer tube
103. Moreover, one end side (base end side) of an exhaust gas line
108 for discharging exhaust gas 11a of the heating gas 11 from
30 the outer tube 103 is connected to the inside of the outer tube
103. Note that a blower (not illustrated) is provided in a system
9
formed o'f the exhaust line 106, the combustion furnace, the heating
gas feed line 107, and the exhaust gas line 108, and the pyrolysis
gas 12, the fine pyrolized coal 2a, the heating gas 11, the exhaust
gas 11a and the like can flow through the exhaust line 106, the
5 heating gas feed line 107, and the exhaust gas line 108.
Moreover, as shown in Figs. 1A and IB, the chute 104 is
provided with a gas flow-velocity regulating device 110 which
sections the chute 104 into a space including a portion
communicating with the inner tube 102 and a space including a
10 portion connected to the exhaust line 106 while allowing the
pyrolysis gas 12 and the fine pyrolized coal 2a to be exhausted
and which can change the sizes of these spaces and regulate a
terminal velocity being a flow velocity of the pyrolysis gas 12.
The gas flow-velocity regulating device 110 includes a motor 111
15 and two partition plates 113, 114 which are provided with one end
sides (base end sides) thereof being connected to an output shaft
112 (shaft body) of the motor 111 and whose other end sides (front
end sides) swing in circumferential directions along the side wall
104b of the chute 104 with rotation of the output shaft 112. Note
20 that the output shaft 112 is formed in a shape extending in a height
direction of the chute 104.
The size of each of the partition plates 113, 114 is
substantially the same as that of a space between the output shaft
112 and the side wall 104b of the chute 104, and the partition
25 plates 113, 114 are plate bodies large enough to extend from the
top plate 104a of the chute 104 to below the portion communicating
with the inner tube 102. The partition plates 113, 114 are made
of the same material as the chute 104 and are made of, for example,
steel plates. The output shaft 112 is rotated by an actuation the
30 motor 111 performed by controlling the motor 111, and the two
partition plates 113, 114 are thereby moved in directions moving
10
away from each other or in directions coming close to each other.
In other words, the front end portion sides of the partition plates
113, 114 are swingable in a horizontal direction.
The aforementioned terminal velocity of the pyrolysis gas
5 12 is the speed at the time when the pyrolysis gas 12 is discharged
from the inside of the chute 104 to the exhaust line 106. The
terminal velocity of the pyrolysis gas 12 changes depending on
the size of a horizontal cross section of a space formed below
the exhaust line 106 by the side wall 104b of the chute 104 and
10 the partition plates 113, 114. There is a correlation between the
terminal velocity of the pyrolysis gas 12 and the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12.
The particle diameter of the fine pyrolized coal 2a entrained in
the pyrolysis gas 12 becomes larger as the terminal velocity of
15 the pyrolysis gas 12 becomes faster, and the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12
becomes smaller as the terminal velocity of the pyrolysis gas 12
becomes slower.
In such an embodiment, the coal pyrolizing device 100 is
20 formed of the hopper 101, the inner tube 102, the outer tube 103,
the chute 104, the gas flow-velocity regulating device 110 and
the like; pyrolized coal discharging means is formed of the chute
104 and the like; gas discharging means is formed of the chute
104, the exhaust line 106, and the like; and the gas flow-velocity
25 regulating device 110 which is gas flow-velocity regulating means
is formed of the motor 111, the output shaft 112, the partition
plates 113, 114, and the like.
Next, main operations of the coal pyrolizing device 100 are
described.
30 The heating gas (about 1000 to 1100°C) 11 is supplied to
the outer tube 103 of the coal pyrolizing device 100, and the dry
11
coal (average particle diameter: about 5 mm, about 150 to 200°C)
1 is put into the hopper 101 and supplied into the inner tube
(cylinder main body) 102. The dry coal 1 is then moved from the
one end side to the other end side of the inner tube 102 while
5 being agitated with rotation of the inner tube 102, and is thereby
thoroughly heated and pyrolized (about 350 to 450°C) by the heating
gas (about 1000 to 1100°C) 11 fed to the outer tube 103 to become
the pyrolized coal (average particle diameter: about 5 mm) 2. The
pyrolized coal 2 is supplied into a hopper (not illustrated) of
10 a cooling device (not illustrated) via the chute 104.
The pyrolysis gas (about 350 to 450°C) 12 generated in the
pyrolysis performed in the inner tube 102 of the coal pyrolizing
device 100 is fed from the upper portion of the chute 104 to the
combustion furnace (not illustrated) through the exhaust line 106,
15 and is combusted together with inert gas (containing carbon
monoxide) and air (and also with the combustion aid as needed)
to be used for the generation of the heating gas 11.
In this case, in the rotary kiln-type coal pyrolizing device
100, temperature drop occurs in a portion (the other end side in
20 an axial direction) of the inner tube 102 which protrudes from
the outer tube 103 without being covered with the outer tube 103
and which is not heated by the heating gas 11 as described above.
Accordingly, the mercury-based substances are
physically-adsorbed onto the pyrolized coal again in the portion
25 (the other end side in an axial direction) of the inner tube which'
protrudes from the outer tube without being covered with the outer
tube and which is not heated by the heating gas. Moreover, even
in a case where no physical adsorption occurs, the mercury-based
substances in the pyrolysis gas are chemically-adsorbed onto the
30 fine pyrolized coal in the pyrolized coal when the temperature
of the pyrolized coal exceeds the limit temperature of chemical
12
adsorption, and the mercury concentration in the pyrolized coal
sent out from the other end side of the inner tube increases.
Moreover, since the space volume of the chute (chamber) is
fixed in the conventional rotary kiln-type coal pyrolizing device,.
5 the space gas flow velocity changes when the operation conditions
of the coal pyrolizing device change, and the particle diameter
of the fine pyrolized coal conveyed by the pyrolysis gas discharged
from the exhaust line is determined depending on the situation.
Hence, it is impossible to control the particle diameter of the
10 fine coal to be separated by an air flow of the pyrolysis gas.
The coal pyrolizing device 100 of the embodiment made in
view of such problems further performs the following operation
to regulate the gas flow velocity of the pyrolysis gas 12 discharged
from the exhaust line 106 and suppress an increase of mercury
15 concentration in the pyrolized coal 2.
The motor 111 is controlled and driven to rotate the output
shaft 112 of the motor 111, and the other end sides of the partition
plates 113, 114 are moved. This adjusts the size of the horizontal
cross section of the space surrounded by the partition plates 113,
20 114 and the side wall 104b of the chute 104 below the exhaust line
106, and the gas flow velocity (terminal velocity) of the pyrolysis
gas 12 flowing toward the exhaust line 106 is thereby regulated.
The dry coal 1 supplied into the hopper 101 moves inside
the inner tube 102 from the one end side to the other end side
25 thereof with the rotation of the inner tube 102 while being
thoroughly heated and pyrolized (about 350 to 450°C) by the heating
gas 11 to become the pyrolized coal 2 as described above. Meanwhile,
the dry coal 1 produces the pyrolysis gas 12 which contains a small
amount of gas of mercury-based substances such as HgS and HgCl2.
30 Then, when the pyrolized coal 2 moves inside the inner tube
102 to the other end side thereof and reaches the portion not heated
13
by the heating gas 11 and the temperature of the pyrolized coal
2 drops, most of the mercury-based substances in the pyrolysis
gas 12 are physically-adsorbed or chemically-adsorbed more to the
fine pyrolized coal 2a than to the pyrolized coal 2, because the
5 fine pyrolized coal 2a in the pyrolized coal (average particle
diameter: about 5 mm) 2 is far smaller than the pyrolized coal
2 and the specific surface area per unit weight of the fine
pyrolized coal 2a is far greater than that of the pyrolized coal
2.
10 Here, referring to Figs. 2 and 3, description is given of
an example of a relationship between the gas flow velocity
(terminal velocity) of the pyrolysis gas 12 in the chute (chamber)
104 which is discharged from the inside of the chute (chamber)
104 to the exhaust line 106 and the particle diameter of the fine
15 pyrolized coal 2a entrained in the pyrolysis gas 12 and an example
of the yield of the pyrolized coal.
First, it is known that the temperature drop of the pyrolized
coal 2 causes re-adsorption of the mercury-based substances in
the pyrolysis gas 12 onto a surface of the pyrolized coal 2 due
20 to the physical adsorption thereof, and a proportion of the'
mercury-based substances re-adsorbed onto the fine pyrolized coal
2a which is the pyrolized coal with a particularly small particle
diameter is great. In view of this, in a case where the particle
diameter of the fine pyrolized coal 2a entrained in the pyrolysis
25 gas 12 discharged from the chute 104 is set to, for example, 150
um, it is found that the fine pyrolized coal 2a having the particle
diameter of 150 um can be entrained in the pyrolysis gas 12 by
setting the gas flow velocity (terminal velocity) of the pyrolysis
gas 12 discharged from the chute 104 to a velocity little less
30 than 0.6 m/s as shown in Fig. 2.
14
Although the particle diameter of the pyrolized coal onto
which a large proportion of the mercury-based substances in the
pyrolysis gas are re-adsorbed changes depending on a pyrolysis
process (pyrolizing -temperature, initial mercury concentration
5 of the pyrolized coal, and the like), it varies substantially
within a range of plus and minus 50 um of the particle diameter
of 150 um. It is thus possible to entrain fine pyrolized coal having
a particle diameter of 100 jam to 200 um in the pyrolysis gas by
controlling the gas flow velocity (terminal velocity) of the
10 pyrolysis gas discharged from the chute within a range of 0.25
m/s to 1.1 m/s, and thereby suppress the increase of mercury
concentration in the produced pyrolized coal, i.e. the pyrolized
coal sent out from a lower portion of the chute.
Moreover, as shown in Fig. 3, when the fine pyrolized coal
15 2a having the particle diameter of 150 um is separated, the yield
of the pyrolized coal 2 is about 92%. Accordingly, it is confirmed
that reduction of production efficiency due to removal of the fine
pyrolized coal 2a from the pyrolized coal 2 can be also suppressed.
Since the particle diameter of the fine pyrolized coal 2a
20 entrained in the pyrolysis gas 12 is adjusted by regulating the
terminal velocity of the pyrolysis gas 12 with the gas
flow-velocity regulating device 110, the fine pyrolized coal 2a
onto which the mercury-based substances are adsorbed is discharged
to the combustion chamber through the exhaust line 106 together
25 with the pyrolysis gas 12. The pyrolized coal 12 sent out from
the chute 104 to the cooling device thus contains no fine pyrolized
coal 2a onto which the mercury-based substances are
physically-adsorbed or chemically-adsorbed. Accordingly, the
increase of mercury concentration in the pyrolized coal 2 can be
30 suppressed.
15
A relationship between the cross-sectional area of the
inside of the chute (chamber) 104 on the exhaust line side and
the gas flow velocity (terminal velocity) in the chute (chamber)
is described with reference to Fig. 4 showing an example of this
5 relationship. The gas flow velocity of the pyrolysis gas at which
the pyrolysis gas can entrain the fine pyrolized coal having a
particle diameter of Dp is referred to as Vt.
When.the operation load of the coal pyrolizing device 100
is 100%, the relationship between the cross-sectional area on the
10 exhaust line 106 side and the gas flow velocity in the chute 104
is expressed by the straight line Lll. From this, it is found that
the gas flow-velocity which is the terminal velocity of the
pyrolysis gas 12 in the chute 104 can be set to Vt by setting the
chute inside cross-sectional area to Al which is within a range
15 that the gas flow-velocity regulating device 110 can change the
cross-sectional area of the inside of the chute 104 on the exhaust
line 106 side.
When the operation load of the coal pyrolizing device 100
is 80%, the relationship between the cross-sectional area on the
20 exhaust line 106 side and the gas flow velocity in the chute 104
is expressed by the straight line L12. From this, it is found that
the gas flow-velocity which is the terminal velocity of the
pyrolysis gas 12 in the chute 104 can be set to Vt by setting the
chute inside cross-sectional area to A2 which is within the range
25 that the gas flow-velocity regulating device 110 can change the
cross-sectional area of the inside of the chute 104 on the exhaust
line 106 side.
When the operation load of the coal pyrolizing device 100
is 60%, the relationship between the cross-sectional area on the
30 exhaust line 106 side and the gas flow velocity in the chute 104
is expressed by the straight line L13. From this, it is found that
16
the gas flow-velocity which is the terminal velocity of the
pyrolysis gas 12 in the chute 104 can be set to Vt by setting the
chute inside cross-sectional area to A3 which is within the range
that the gas flow-velocity regulating device 110 can change the
5 cross-sectional area of the inside of the chute 104 on the exhaust
line 106 side.
In summary, it is found that, although the amount of
pyrolysis gas generated in the inner tube 102 decreases as the
operation load of the coal pyrolizing device 100 becomes lower,
10 even in such a case, the gas flow velocity of the pyrolysis gas
12 at which the fine pyrolized coal 2a having the particle diameter
of Dp can be entrained can be maintained by making the
cross-sectional area of the inside of the chute 104 on the exhaust
line 106 side variable. In other words, it is found that the gas
15 flow velocity in the chute 104 on the exhaust line 106 side can
be maintained at the terminal velocity Vt of the particle diameter
Dp, irrespective of the operation load of the coal pyrolizing
device 100, and the fine pyrolized coal 2a having a particle
diameter equal to or smaller than Dp can be thereby entrained in
20 the pyrolysis gas 12.
Meanwhile, the fine pyrolized coal 2a onto • which the
mercury-based substances are physically-adsorbed or
chemically-adsorbed is fed from the upper portion of the chute
104 of the coal pyrolizing device 100 to the combustion furnace
25 through the exhaust line 106 together with the pyrolysis gas 12
and, as described above, combusted together with the inert gas
(including nitrogen, carbon monoxide, and the like) and air (and
also with the combustion aid as needed) to be used for the
generation of the heating gas 11. At this time, the mercury-based
30 substances such as HgS and HgCl2 adsorbed onto the fine pyrolized
coal 2a exist as gaseous Hg in the heating gas 11 with the combustion.
17
The heating gas 11 is processed in an exhaust gas processing device
after being used for the heating of the inner tube 102 of the coal
pyrolizing device 100, substituted with mercury chloride, calcium
sulfate, and the like to be collected, and then discharged to the
5 outside of the system.
In the embodiment, the following is thus achieved. When the
temperature of the pyrolized coal 2 drops in the portion not heated
by the heating gas 11, most of the mercury-based substances in
the pyrolysis gas 12 are physically-adsorbed or
10 chemically-adsorbed onto the fine pyrolized coal 12a in the
pyrolized coal 12 because the particle diameter of the fine
pyrolized coal 2a is far smaller than the average particle diameter
and the specific surface area per unit weight of the fine pyrolized
coal 2a is far greater than that of the pyrolized coal of the average
15 particle diameter. However, since the particle diameter of the
fine pyrolized coal 2a entrained in the pyrolysis gas 12 can be
adjusted by regulating the gas flow velocity of the pyrolysis gas
12 discharged from the exhaust line 106 by adjusting the
cross-sectional area of the inside of the chute 104 on the exhaust
20 line 106 side with the partition plates 113, 114 of the gas
flow-velocity regulating device 110, it is possible to entrain,
in the pyrolysis gas 12, the fine pyrolized coal 2a whose particle
diameter is far smaller than the average particle diameter of the
pyrolized coal and whose specific surface area per unit weight
25 is far greater than that of the pyrolized coal of the average
particle diameter, and separate the fine pyrolized coal 2a from
the pyrolized coal 2 . Hence, the increase of mercury concentration
in the produced pyrolized coal 2 can be suppressed.
30
18
SECOND EMBODIMENT
A second embodiment of the coal pyrolizing device of the
present invention is described based on Figs . 5A and 5B. Note that,
in the embodiment, the same members as those in the coal pyrolizing
5 device of the aforementioned first embodiment are denoted by the
same reference numerals and description thereof is omitted as
appropriate.
As shown in Figs. 5A and 5B, a coal pyrolizing device 200
of the embodiment includes a chute 204 which is connected to the
10 other end side (front end side) of the inner tube 102 to allow
the inner tube 102 to rotate and which sends out pyrolized coal
2 by causing the pyrolized coal 2 to fall from the other end side
(front end side) of the inner tube 102. Note that side walls 204b,
204c, and 204d of the chute 204 each form a flat surface.
15 The chute 204 is provided with a gas flow-velocity regulating
device 210 which sections the chute 204 into a space including
a portion communicating with the inner tube 102 and a space
including a portion connected to the exhaust line 106 while
allowing the pyrolysis gas 12 and the fine pyrolized coal 2a to
20 be exhausted and which can change the sizes of these spaces and
regulate the terminal velocity being the flow velocity of the
pyrolysis gas 12. The gas flow-velocity regulating device 210
includes a drive cylinder 211, a cylinder rod (shaft body) 212
of the drive cylinder 211, and a partition plate 213 which is
25 provided on the cylinder rod 212 and which advances and retreats
in front-rear directions along a top plate 204a and the side walls
204c, 204d of the chute 104 with advance and retreat of the cylinder
rod 212. Note that the cylinder rod 212 is formed in a shape
extending toward the inner tube 102.
30 The size of the partition plate 213 is substantially the
same as that of a space between the side walls 204c, 204d of the
19
chute 204, and the partition plate 213 is a plate body large enough
to extend from the top plate 204a of the chute 204 to below the
portion communicating with the inner tube 102 . The partition plate
213 is made of the same material as the chute 204 and is made of,
5 for example, a steel plate. When the cylinder rod 212 is extended
by an actuation the drive cylinder 211 performed by controlling
the drive cylinder 211, the partition plate 213 is moved toward
the inner tube 102 with this extension. When the cylinder rod 212
is contracted, the partition plate 213 is moved away from the inner
10 tube 102 with this contraction and is moved toward the side wall
204b of the chute 204.
The aforementioned terminal velocity of the pyrolysis gas
12 is the speed at the time when the pyrolysis gas 12 is discharged
from the inside of the chute 204 to the exhaust line 106 as in
15 the aforementioned first embodiment. The terminal velocity of the
pyrolysis gas 12 changes depending on the size of a horizontal
cross section of a space formed below the exhaust line 106 by the
chute 204 and the partition plate 213. There is a correlation
between the terminal velocity of the pyrolysis gas 12 and the
20 particle diameter of the fine pyrolized coal 12a entrained in the
pyrolysis gas 12. The particle diameter of the fine pyrolized coal
2a entrained in the pyrolysis gas 12 becomes larger as the terminal
velocity of the pyrolysis gas 12 becomes faster, and the particle
diameter of the fine pyrolized coal 2a entrained in the pyrolysis
25 gas 12 becomes smaller as the terminal velocity of the pyrolysis
gas 12 becomes slower.
Note that, in the embodiment, the coal pyrolizing device
200 is formed of the hopper 101, the inner tube 102, the outer
tube 103, the chute 204, the gas flow-velocity regulating device
30 210, and the like; the pyrolized coal discharging means is formed
of the chute 204 and the like; the gas discharging means is formed
20
of the chute 204, the exhaust line 106, and the like; and the gas
flow-velocity regulating device 210 which is the gas flow-velocity
regulating means is formed of the drive cylinder 211, the cylinder
rod 212, the partition plate 213, and the like.
5 The coal pyrolizing device 200 of the embodiment including
the gas flow-velocity regulating device 210 described above can
produce the pyrolized coal 2 from the dry coal 1 by performing
main operations as in the case of the coal pyrolizing device 100
of the aforementioned first embodiment.
10 Moreover, the cylinder rod 212 is extended and contracted
by the actuation the drive cylinder 211, and the partition plate
213 is advanced toward and retreated from the inner tube 102 of
the chute 204 to adjust the size of the horizontal cross section
of the region surrounded by the partition plate 213 and the chute
15 204 below 'the exhaust line 106. The terminal velocity of the
pyrolysis gas 12 is thereby regulated and the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12
is adjusted depending on the terminal velocity of the pyrolysis
gas 12. The mercury-based substances in the pyrolysis gas 12 are
20 physically-adsorbed onto the pyrolized coal in the portion of the
inner tube 102 close to the other end where the temperature drops
from that in the center of the inner tube 102 in the axial direction,.
i.e. the portion not covered with the outer tube 103 and not heated
by the heating gas 11. However, the mercury-based substances are
25 physically-adsorbed onto the fine pyrolized coal 2a of the
pyrolized coal 2, and the fine pyrolized coal 2a is entrained in
the pyrolysis gas 12 to be discharged from the exhaust line 106
to the combustion furnace. In other words, the pyrolized coal 2
sent out from a lower portion of the chute 204 is coal onto which
30 only a small amount of the mercury-based substances are adsorbed.
21
Accordingly, in the embodiment, as in the aforementioned
embodiment, since the particle diameter of the fine pyrolized coal
2a entrained in the pyrolysis gas 12 can be adjusted by regulating
the gas flow velocity of the pyrolysis gas 12 discharged from the
5 exhaust line 106 by adjusting the cross-sectional area of the
inside of the chute'204 on the exhaust line 106 side with the
partition plate 213 of the gas flow-velocity regulating device
210, it is possible to entrain, in the pyrolysis gas 12, the fine
pyrolized coal 2a whose particle diameter is far smaller than the
10 average particle diameter of the pyrolized coal and whose specific
surface area per unit weight is far greater than that of the
pyrolized coal of the average particle diameter, and separate the
fine pyrolized coal 2a from the pyrolized coal 2. Hence, the
increase of mercury concentration in the produced pyrolized coal
15 2 can be suppressed.
THIRD EMBODIMENT
A third embodiment of the coal pyrolizing device of the
present invention is described based on Figs. 6A and 6B. Note that,
20 in the embodiment, the same members as those in the coal pyrolizing
device of the aforementioned second embodiment are denoted by the
same reference numerals and description thereof is omitted as
appropriate.
As shown in Figs. 6A and 6B, a coal pyrolizing device 300
25 of the embodiment includes a gas flow-velocity regulating device
310 provided in the chute 204. The gas flow-velocity regulating
device 310 sections the chute 204 into a space including a portion
communicating with the inner tube 102 and a space including a
portion connected to the exhaust line 106 while allowing the
30 pyrolysis gas 12 and the fine pyrolized coal 2a to be exhausted
22
and can change the sizes of these spaces and regulate the terminal
velocity being the flow velocity of the pyrolysis gas 12.
The gas flow-velocity regulating device 310 includes a motor
311, an output shaft (shaft body) 312 of the motor 311, and a
5 partition plate 313 which is provided on the output shaft 312 and
whose one end portion side (upper end portion side) and the other
end portion side (lower end portion side) swing in directions
advancing toward and retreating from the inner tube 102 with
rotation of the output shaft 312. Note that the output shaft 312
10 is formed in a shape'extending between the side walls 204c, 204d
of the chute 204.
The size of the partition plate 313 is substantially the
same as that of the space between the side walls 204c, 204d of
the chute 204, and the partition plate 313 is a plate body large
15 enough to extend from the top plate 204a of the chute 204 to below
the portion communicating with the inner tube 102. The partition
plate 313 is made of the same material as the chute 204 and is
made of, for example, a steel plate. When the output shaft 312
is rotated by an actuation the motor 311 performed by controlling
20 the motor 311, the one end portion side (upper end portion side)
or the other end portion side (lower end portion side) of the
partition plate 313.moves toward the inner tube 102 with this
rotation. Note that the partition plate 313 is configured such
that a side surface portion of the one end portion side (upper
25 end portion side) of the partition plate 313 can face a portion
below the exhaust line 106 when the other end portion side (lower
end portion side) of .the partition plate 313 swings toward the
inner tube 102. In this case, part of the pyrolysis gas 12 flowing
from the inner tube 102 into the chute 104 flows to the exhaust
30 line 106 by going around the other end portion side (lower end
portion side) of the partition plate 313 via a portion therebelow,
23
and the remainder of the pyrolysis gas 12 hits a side surface
portion of the partition plate 313 to be guided toward the exhaust
line 106.
The aforementioned terminal velocity of the pyrolysis gas
5 12 is the speed at the time when the pyrolysis gas 12 is discharged
from the inside of the chute 204 to the exhaust line 106, and changes
depending on the size of a portion which is a horizontal cross
section of a space formed below the exhaust line 106 by the chute
204 and the partition plate 313 and which is the smallest. There
10 is a correlation between the terminal velocity of the pyrolysis
gas 12 and the particle diameter of the fine pyrolized coal 2a
entrained in the pyrolysis gas 12. The particle diameter of the
fine pyrolized coal 2a entrained in the pyrolysis gas 12 becomes
larger as the terminal velocity of the pyrolysis gas 12 becomes
15 faster, and the particle diameter of the fine pyrolized coal 2a
entrained in the pyrolysis gas 12 becomes smaller as the terminal
velocity of the pyrolysis gas 12 becomes slower.
Note that, in the embodiment, the coal pyrolizing device
300 is formed of the hopper 101, the inner tube 102, the outer
20 tube 103, the chute 204, the gas flow-velocity regulating device
310, and the like; the pyrolized coal discharging means is formed
of the chute 204 and the like; the gas discharging means is formed
of the chute 204, the exhaust line 106, and the like; and the gas
flow-velocity regulating device 310 which is the gas flow-velocity
25 regulating means is formed of the motor 311, the output shaft 312,
the partition plate'313, and the like.
The coal pyrolizing device 300 of the embodiment including
the gas flow-velocity regulating device 310 described above can
produce the pyrolized coal 2 from the dry coal 1 by performing
30 main operations as in the case of the coal pyrolizing device 200
of the aforementioned second embodiment.
24
Moreover, the output shaft 312 is rotated by the actuation
the motor 311, and the partition plate 313 is swung to adjust the
size of the horizontal cross section of the region surrounded by
the partition plate 313 and the chute 204. The terminal velocity
5 of the pyrolysis gas 12 is thereby regulated, and the particle
diameter of the fine pyrolized coal 2a entrained in the pyrolysis
gas 12 is set depending on the terminal velocity of the pyrolysis
gas 12. The mercury-based substances in the pyrolysis gas 12 are
physically-adsorbed onto the pyrolized coal in the portion of the
10 inner tube 102 close to the other end where the temperature drops
from that in the center of the inner tube 102 in the axial direction,
i.e. the portion not covered with the outer tube 103 and not heated
by the heating gas 11. However, the mercury-based substances are
physically-adsorbed onto the fine pyrolized coal 2a of the
15 pyrolized coal 2, and the fine pyrolized coal 2a is entrained in
the pyrolysis gas 12 to be discharged from the exhaust line 106
to the combustion furnace. In other words, the pyrolized coal 2
sent out from a lower portion of the chute 204 is coal onto which
only a small amount of the mercury-based substances are adsorbed.
20 Accordingly, in the embodiment, as in the aforementioned
embodiments, since the particle diameter of the fine pyrolized
coal 2a entrained in the pyrolysis gas 12 can be adjusted by
regulating the gas flow velocity of the pyrolysis gas 12 discharged
from the exhaust line 106 by adjusting the cross-sectional area
25 of the inside of the chute 204 on the exhaust line 106 side with
the partition plate 313 of the gas flow-velocity regulating device
310, it is possible to entrain, in the pyrolysis gas 12, the fine
pyrolized coal 2a whose particle diameter is far smaller than the
average particle diameter of the pyrolized coal and whose specific
30 surface area per unit weight is far greater than that of the
pyrolized coal of the average particle diameter, and separate the
25
fine pyrolized coal 2a from the pyrolized coal 2. Hence, the
increase of mercury concentration in the produced pyrolized coal
2 can be suppressed.
5 FOURTH EMBODIMENT
A fourth embodiment of the coal pyrolizing device of the
present invention is described based on Figs. 7A and 7B. Note that,
in the embodiment, the same members as those in the coal pyrolizing
device of the aforementioned third embodiment are denoted by the
10 same reference numerals and description thereof is omitted as
appropriate.
As shown in Figs. 7A and 7B, a coal pyrolizing device 400
of the embodiment includes a gas flow-velocity regulating device
410 provided in the chute 204. The gas flow-velocity regulating
15 device 410 sections the chute 204 into a space including a portion
communicating with the inner tube 102 and a space including a
portion connected to the exhaust line 106 while allowing the
pyrolysis gas 12 and the fine pyrolized coal 2a to be exhausted
and can change the sizes of these spaces and regulate the terminal
20 velocity being the flow velocity of the pyrolysis gas 12.
The gas flow-velocity regulating device 410 includes
multiple (three in the illustrated example) sets each formed of
a motor 411, an output shaft (shaft body) 412 of the motor 411,
and a partition plate 413 which is provided on the output shaft
25 412 and whose one end portion side (upper end portion side) and
the other end portion side (lower end portion side) swing in
directions advancing toward and retreating from the inner tube
102 with rotation of the output shaft 412. These sets are provided
adjacent to one another in the height direction of the chute 204.-
30 The bottom set is provided below the portion of the chute 204
communicating with the inner tube 102. Note that the output shafts
26
412 are each formed in a shape extending between the side walls
204c, 204d of the chute 204.
Each of the partition plates 413 is a plate body having
substantially the same size as the space between the side walls
5 204c, 204d of the chute 204. The partition plates 413 are made
of the same material as the chute 204 and are made of, for example,
steel plates. When each of the output shafts 412 is rotated by
an actuation the corresponding motor 411 performed by controlling
motor 411, the one end portion side (upper end portion side) or
10 the other end portion side (lower end portion side) of the
corresponding partition plate 413 moves toward the inner tube 102
with this rotation.
As in the case of the aforementioned gas flow-velocity
regulating device 310, the aforementioned terminal velocity of
15 the pyrolysis gas 12 is the speed at the time when the pyrolysis
gas 12 is discharged from the inside of the chute 204 to the exhaust
line 106, and changes depending on the size of a portion which
is a horizontal cross section of a space formed below the exhaust
line 106 by the chute 204 and each of the partition plates 413
20 and which is the smallest. There is a correlation between the
terminal velocity of the pyrolysis gas 12 and the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12.
The particle diameter of the fine pyrolized coal 2a entrained in
the pyrolysis gas 12 becomes larger as the terminal velocity of
25 the pyrolysis gas 12 becomes faster, and the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12
becomes smaller as the terminal velocity of the pyrolysis gas 12
becomes slower.
Note that, in the embodiment, the coal pyrolizing device
30. 400 is formed of the hopper 101, the inner tube 102, the outer
tube 103, the chute 204, the gas flow-velocity regulating device
27
410 and the like; the pyrolized coal discharging means is formed
of the chute 204 and the like; the gas discharging means is formed
of the chute 204, the exhaust line 106, and the like; and the gas
flow-velocity regulating device 410 which is the gas flow-velocity
5 regulating means is formed of the motors 411, the output shafts
412, the partition plates 413, and the like.
The coal pyrolizing device 400 of the embodiment including
the gas flow-velocity regulating device 410 described above can
produce the pyrolized coal 2 from the dry coal 1 by performing
10 main operations as in the case of the coal pyrolizing device 300
of the aforementioned third embodiment.
Moreover, each of the output shafts 412 is rotated by the
actuation the corresponding motor 411, and the corresponding
partition plate 413 is swung to adjust the size of the horizontal
15 cross section of the region surrounded by the partition plate 413
and the chute 204. The terminal velocity of the pyrolysis gas 12
is thereby regulated, and the particle diameter of the fine
pyrolized coal 2a entrained in the pyrolysis gas 12 is set depending
on the terminal velocity of the pyrolysis gas 12 . The mercury-based
20 substances in the pyrolysis gas 12 are physically-adsorbed onto
the pyrolized coal in the portion of the inner tube 102 close to
the other end where the temperature drops from that in the center
of the inner tube 102 in the axial direction, i.e. the portion
not covered with the outer tube 103 and not heated by the heating.
25 gas 11. However, the mercury-based substances are
physically-adsorbed onto the fine pyrolized coal 2a of the
pyrolized coal 2, and the fine pyrolized coal 2a is entrained in
the pyrolysis gas 12 to be discharged from the exhaust line 106
to the combustion furnace. In other words, the pyrolized coal 2
30 sent out from a lower portion of the chute 204 is coal onto which
only a small amount of the mercury-based substances are adsorbed.
28
Accordingly, in the embodiment, as in the aforementioned
embodiments, since the particle diameter of the fine pyrolized
coal 2a entrained in the pyrolysis gas 12 can by adjusted by
regulating the gas flow velocity of the pyrolysis gas 12 discharged
5 from the exhaust line 106 by adjusting the cross-sectional area
of the inside of the chute 204 on the exhaust line 106 side with
the partition plates 413 of the gas flow-velocity regulating
device 410, it is possible to entrain, in the pyrolysis gas 12,
the fine pyrolized coal 2a whose particle diameter is far smaller
10 than the average particle diameter of the pyrolized coal and whose
specific surface area per unit weight is far greater than that
of the pyrolized coal of the average particle diameter, and
separate the fine pyrolized coal 2a from the pyrolized coal 2.
Hence, the increase of mercury concentration in the produced
15 pyrolized coal 2 can be suppressed.
FIFTH EMBODIMENT
A fifth embodiment of the coal pyrolizing device of the
present invention is described based on Fig. 8. Note that, in the
20 embodiment, the same members as those in the coal pyrolizing device
of the aforementioned second embodiment are denoted by the same
reference numerals and description thereof is omitted as
appropriate.
As shown in Fig. 8, a coal pyrolizing device 500 of the
25 embodiment includes a gas flow-velocity regulating device 510
including a gas flow-velocity detector (gas flow-velocity sensor)
521 which is provided in the exhaust line 106 and which detects
the flow velocity of the pyrolysis gas 12 flowing in the exhaust
line 106, a flow meter 522 which is electrically connected to the
30 gas flow-velocity detector 521, and a control device 523 whose
input side is electrically connected to the flow meter 522 and
29
whose output side is electrically connected to the drive cylinder
211.
Note that, in the embodiment, the coal pyrolizing device
500 is formed of the hopper 101, the inner tube 102, the outer
5 tube 103, the chute 204, the gas flow-velocity regulating device
510 and the like; the pyrolized coal discharging means is formed
of the chute 204 and the like; the gas discharging means is formed
of the chute 204, the exhaust line 106, and the like; the gas
flow-velocity regulating device 510 which is the gas flow-velocity
10 regulating means is formed of the drive cylinder 211, the output
shaft 212, the partition plate 213, the gas flow-velocity detector
521, the flow meter 522, the control device 523, and the like:
gas state detecting means is formed of the gas flow-velocity
detector 521, the flow meter 522, the control device 523 and the
15 like; and control means is formed of the control device 523 and
the like.
The coal pyrolizing device 500 of the embodiment including
the gas flow-velocity regulating device 510 described above can
produce the pyrolized coal 2 from the dry coal 1 by performing
20 main operations as in the case of the coal pyrolizing device 200
of the aforementioned second embodiment.
When the gas flow-velocity detector 521 detects the flow
velocity of the pyrolysis gas 12 flowing in the exhaust line 106,
the detection value df this flow velocity is displayed on the flow
25 meter 522 and is also sent to the control device 523. The control
device 523 causes the partition plate 213 to be moved by the
actuation the drive cylinder 211 on the basis of the detection
value and adjusts the size of the horizontal cross section of the
region surrounded by the partition plate 313 and the chute 204.
30 The terminal velocity of the pyrolysis gas 12 is thereby regulated,
and the particle diameter of the fine pyrolized coal 2a entrained
30
in the pyrolysis gas 12 is adjusted depending on the terminal
velocity of the pyrolysis gas 12. The mercury-based substances
in the pyrolysis gas 12 are physically-adsorbed onto the pyrolized
coal in the portion of the inner tube 102 close to the other end
5 where the temperature drops from that in the center of the inner
tube 102 in the axial direction, i.e. the portion not covered with
the outer tube 103 and not heated by the heating gas 11. However,
the mercury-based substances are physically-adsorbed onto the
fine pyrolized coal 2a of the pyrolized coal 2, and the fine
10 pyrolized coal 2a is entrained in the pyrolysis gas 12 to be
discharged from the exhaust line 106 to the combustion furnace..
In other words, the pyrolized coal 2 sent out from a lower portion
of the chute 204 is coal onto which only a small amount of the
mercury-based substances are adsorbed.
15 Accordingly, in the embodiment, since the particle diameter
of the fine pyrolized coal 2a entrained in the pyrolysis gas 12
can be adjusted by regulating the gas flow velocity of the pyrolysis
gas 12 discharged from the exhaust line 106 by causing the control
device 523 to control the actuation the drive cylinder 211
20 depending on the flow velocity of the pyrolysis gas 12 flowing
through the exhaust line 106 which is detected by the gas
flow-velocity detector 521 and adjust the cross-sectional area
of the inside of the chute 204 on the exhaust line 106 side with
the partition plate 213, it is possible to entrain, in the pyrolysis
25 gas 12, the fine pyrolized coal 2a whose particle diameter is far
smaller than the average particle diameter of the pyrolized coal
and whose specific surface area per unit weight is far greater
than that of the pyro'lized coal of the average particle diameter,
and separate the fine pyrolized coal 2a from the pyrolized coal
30 2. Hence, the increase of mercury concentration in the produced
pyrolized coal 2 can be surely suppressed.
31
SIXTH EMBODIMENT
A sixth embodiment of the coal pyrolizing device of the
present invention is described based on Figs. 9A, 9B, 10, and 11.
Note that, in the embodiment, the same members as those in the
5 coal pyrolizing device of the aforementioned second embodiment
are denoted by the same reference numerals and description thereof
is omitted as appropriate.
As shown in Figs. 9A and 9B, a coal pyrolizing device 600
of the embodiment includes a gas flow-velocity regulating device
10 610 which is provided on the chute 204. The gas flow-velocity
regulating device 610 sections the chute 204 into a space including
a portion communicating with the inner tube 102 and a space
including a portion connected to the exhaust line 106 while
allowing the pyrolysis gas 12 and the fine pyrolized coal 2a to
15 be exhausted and can change the sizes of these spaces and regulate'
an entrance flow velocity of the pyrolysis gas 12 into a centrifuge
612.
The gas flow-velocity regulating device 610 includes a feed
pipe 611 which is connected to the top plate 204a of the chute
20 204, the centrifuge 612 which is connected to the feed pipe 611,
a partition plate (shield wall) 615 which is provided in the feed
pipe 611 to be movable by a drive cylinder 616, a discharge pipe
617 whose one end portion side is connected to the centrifuge 612
and which is connected to the side wall 204b of the chute 204,
25 and a rotary valve 618 which is provided in the middle of the
discharge pipe 617 . The centrifuge 612 includes an inner tube 614
which has a small diameter and whose one end portion side (frontend
portion side) is connected to the exhaust line 106 and an outer
tube 613 which covers the inner tube 614 and whose one end portion
30 side (upper end portion side) and other end portion side (lower
32
end portion side) are connected respectively to the feed pipe 611
and the discharge pipe 617.
The partition plate 615 is a plate body formed in a shape
larger than the diameter of the feed pipe 611. The partition plate
5 615 is made of the same material as the chute 204 and is made of,
for example, a steel plate. When a cylinder rod of the drive
cylinder 616 is extended by the actuation the drive cylinder 616,
the partition plate 615 is moved with this extension to block the
feed pipe 611. When the cylinder rod is contracted, the partition
10 plate 615 is moved with this contraction to fully open the feed
pipe 611. In other words, the partition plate 615 can adjust a
radial cross-sectional area through which the pyrolysis gas 12
and the fine pyrolized coal 2a can flow in the feed pipe 611.
The aforementioned entrance flow velocity of the pyrolysis
15 gas 12 into the centrifuge 612 is the speed at the time when the
pyrolysis gas 12 flows from the inside of the chute 204 into
centrifuge 612 through the feed pipe 611 of the gas flow-velocity
regulating device 610, and changes depending on the size of the
radial cross-sectional area of a space formed by the feed pipe
20 611 and the partition plate 615. There is a correlation between
the entrance flow velocity into the centrifuge 612 determined by
the partition plate 615 of the feed pipe 611 which is the entrance
flow velocity of the joyrolysis gas 12 into the centrifuge 612 and
the particle diameter of the fine pyrolized coal 2a entrained in
25 the pyrolysis gas 12, in other words, the particle diameter of
the pyrolized coal collectable by the centrifuge 612 (collection
limit particle diameter) . As shown in Fig. 10, in centrifugation
of fine particles by.the centrifuge 612, the collection limit
particle diameter becomes smaller in proportion to the one-half
30 power to the entrance flow velocity Vi at the partition plate 615
of the feed pipe 611. In other words, as the entrance flow velocity
33
becomes faster, the limit of the collectable particle diameter
becomes smaller and the particle diameter of the fine pyrolized
coal 2a not-collected and entrained in the pyrolysis gas 12 becomes
smaller. Accordingly,, it is possible to change the entrance flow
5 velocity and control the collectable particle diameter (i.e. the
particle diameter of the fine pyrolized coal not collected and
conveyed to the pyrolysis gas •side) by making the radial
cross-sectional area of the feed pipe 611 variable by using the
partition plate 615. When the entrance flow velocity of the
10 pyrolysis gas 12 into the centrifuge 612 becomes faster, the
particle diameter of the fine pyrolized coal 2a entrained in the
pyrolysis gas 12 becomes smaller. When the entrance flow velocity
of the pyrolysis gas 12 into the centrifuge 612 becomes slower,
the particle diameter of the fine pyrolized coal 2a entrained in
15 the pyrolysis gas 12* becomes greater.
Note that, in the embodiment, the coal pyrolizing device 600
is formed of the hopper 101, the inner tube 102, the outer tube
103, the chute 204, the gas flow-velocity regulating device 610,
and the like; the pyrolized coal discharging means is formed of
20 the chute 204 and the like; the gas discharging means is formed
of the chute 204, the exhaust line 106, the gas flow-velocity
regulating device 610, and the like; the gas flow-velocity
regulating device 610 which is the gas flow-velocity regulating
means is formed of the feed pipe 611, the centrifuge 612, the outer
25 tube 613, the inner tube 614, the partition plate (shield wall)
615, the drive cylinder 616, the discharge pipe 617, the rotary
valve 618, and the like.
The coal pyrolizing device 600 of the embodiment including
the gas flow-velocity regulating device 610 described above can
30 produce the pyrolized coal 2 from the dry coal 1 by performing
34
main operations as in the case of the coal pyrolizing device 200
of the aforementioned second embodiment.
A relationship between the cross-sectional area (entrance
cross-sectional area of the centrifuge 612) of the feed pipe 611
5 determined by the partition plate 615 and the entrance flow
velocity into the centrifuge 612 which is the gas flow velocity
of the pyrolysis gas 12, discharged to the exhaust line side through
the feed pipe 611, at'the partition plate 615 is described with
reference to Fig. 11 showing an example of the relationship. The
10 gas flow velocity of the pyrolysis gas at which the pyrolysis gas
can entrain and collect the fine pyrolized coal having a particle
diameter of Dc is referred to as Vc.
When the operation load of the coal pyrolizing device 600
is 100%, the relationship between the cross-sectional area of the
15 entrance of the centrifuge 612 determined by the partition plate
(shield wall) 615 of the feed pipe 611 and the gas flow velocity
in the feed pipe 611 forming the entrance of the centrifuge 612
is expressed by the straight line L21. From this, it is found that
the gas flow velocity which is the entrance flow velocity of the
20 pyrolysis gas 12 into the centrifuge 612 in the feed pipe 611 can
be set to Vc by setting the cross-sectional area of the feed pipe
611 to Acl which is within a range that the partition plate 615
of the gas flow-velocity regulating device 610 can change the
cross-sectional area of the inside of the feed pipe 611.
25 When the operation load of the coal pyrolizing device 600
is 80%, the relationship between the cross-sectional area of the.
entrance of the centrifuge 612 determined by the partition plate
(shield wall) 615 of the feed pipe 611 and the gas flow velocity
in the feed pipe 611 forming the entrance of the centrifuge 612
30 is expressed by the straight line L22. From this, it is found that
the gas flow velocity which is the entrance flow velocity of the
35
pyrolysis gas 12 into the centrifuge 612 in the feed pipe 611 can
be set to Vc by setting the cross-sectional area of the feed pipe
611 to Ac2 which is within the range that the partition plate 615
of the gas flow-velocity regulating device 610 can change the
5 cross-sectional area of the inside of the feed pipe 611.
When the operation load of the coal pyrolizing device 600
is 60%, the relationship between the cross-sectional area of the
entrance of the centrifuge 612 determined by the partition plate
(shield wall) 615 of the feed pipe 611 and the gas flow velocity
10 in the feed pipe 611, forming the entrance of the centrifuge 612
is expressed by the straight line L23. From this, it is found that
the gas flow velocity which is the entrance flow velocity of the
pyrolysis gas 12 into the centrifuge 612 in the feed pipe 611 can
be set to Vc by setting the cross-sectional area of the feed pipe
15 611 to Ac3 which is within the range that the partition plate 615
of the gas flow-velocity regulating device 610 can change the
cross-sectional area of the inside of the feed pipe 611.
In summary, it is found that, although the amount of the
pyrolysis gas generated in the inner tube 102 decreases when the
20 operation load of the coal pyrolizing device 600 falls to or below
a rated value, even in such a case, the entrance flow velocity
of the pyrolysis gas^l2 into the centrifuge 612 at which the fine
pyrolized coal 2a having the particle diameter of Dc can be
entrained can be maintained by making the cross section of the
25 feed pipe 611 variable. In other words, it is found that the gas
flow velocity at the entrance of the centrifuge 612 can be
maintained at the velocity Vc at which the pyrolized coal having
the particle diameter of Dc can be collected, irrespective of the
operation load of the coal pyrolizing device 600, and the fine
30 pyrolized coal 2a having a diameter equal to or smaller than Dc
can be thereby entrained in the pyrolysis gas 12.
36
Meanwhile, the fine pyrolized coal 2a onto which the
mercury-based sub'stances are physically-adsorbed or
chemically-adsorbed is fed from the upper portion of the chute
204 of the coal pyrolizing device 600 to the combustion furnace
5 through the exhaust line 106 together with the pyrolysis gas 12
and, as described above, combusted together with the inert gas
(including nitrogen, carbon monoxide, and the like) and air (and
also with the combustion aid as needed) to be used for the
generation of the heating gas. At this time, the mercury-based
10 substances such as HgS and HgCl2 adsorbed onto the fine pyrolized
coal 2a exist as gaseous Hg in the heating gas 11 with the combustion.
The heating gas 11 is processed in the exhaust gas processing device
after being used for the heating of the inner tube 102 of the coal
pyrolizing device 600, substituted with mercury chloride, calcium
15 sulfate, and the like to be collected, and then discharged to the
outside of the system.
In the embodiment, the following is thus achieved. When the
temperature of the pyrolized coal 2 drops in the portion not heated
by the heating gas 11, most of the mercury-based substances in
20 the pyrolysis gas 12 are physically-adsorbed or
chemically-adsorbed onto the fine pyrolized coal 12a in the
pyrolized coal 12 because the particle diameter of the fine
pyrolized coal 2a is far smaller than the average particle diameter
and the specific surface area per unit weight of the fine pyrolized
25 coal 2a is far greater than that of the pyrolized coal of the average
particle diameter. However, since the particle diameter of the
fine pyrolized coal 2a entrained in the pyrolysis gas 12 can be
adjusted by regulating the gas flow velocity of the pyrolysis gas
12 discharged from the feed pipe 611 toward the exhaust line 106
30 by adjusting the radial cross-sectional area of the inside of the
feed pipe 611 with the partition plate 615 of the gas flow-velocity
37
regulating device 610, it is possible to entrain, in the pyrolysis'
gas 12, the fine pyrolized coal 2a whose particle diameter is far
smaller than the average particle diameter of the pyrolized coal
and whose specific surface area per unit weight is far greater
5 than that of the pyrolized coal of the average particle diameter,
and separate the fine pyrolized coal 2a from the pyrolized coal
2. Hence, the increase of mercury concentration in the produced
pyrolized coal 2 can be suppressed.
10 OTHER EMBODIMENTS
The aforementioned gas flow-velocity regulating device 510
can be applied to the aforementioned gas flow-velocity regulating
devices 110, 310, 410, and 610.
In the above description, description is given by using the
15 coal pyrolizing device 400 including the gas flow-velocity
regulating device 410 which has the three sets each of formed of
the output shaft 412 and the partition plate 413. However, the
number of the sets each formed of the output shaft 412 and the
partition plate 413 is.not limited to three and the coal pyrolizing
20 device may include a gas flow-velocity regulating device in which
the number of the sets is two or four or more.
In the above description, description is given by using the
coal pyrolizing device 300 including the gas flow-velocity
regulating device 310 having the partition plate 313 in which the
25 output shaft 312 is provided in a substantially center portion
and whose one end portion side (upper end portion side) and other
end portion side (lower end portion side) are swingable. However,
the coal pyrolizing device may include a gas flow-velocity
regulating device having a partition plate in which an output shaft
30 is provided on one end portion side (upper end portion side) and
whose other end portion side (lower end portion side) is swingable.
38
INDUSTRIAL APPLICABILITY
Since the coal pyrolizing devices of the present invention
can suppress the increase of mercury concentration in the produced
5 pyrolized coal, the coal pyrolizing devices can be very useful
in various industries.
39
WE CLAIM:
1. A rotary kiln-type coal pyrolizing device characterized in
that
5 an inner tube is rotatably supported inside an outer tube,
heating gas is supplied into the outer tube,
coal is supplied into the inner tube from one end side
of the inner tube and is heated and pyrolized while being
agitated and moved from the one end side to another end side
10 of the inner tube by rotating the inner tube,
pyrolized coal and pyrolysis gas are sent out from the
other end side qf the inner tube, and
the coal pyrolizing device comprises:
pyrolized coal discharging means, provided to be
15 connected to the other end side of the inner tube, for
discharging the pyrolized coal;
gas discharging means, provided to be connected to the
pyrolized coal discharging means, for discharging the
pyrolysis gas; and
20 gas flow-velocity regulating means, provided in the'
pyrolized coal discharging means, for regulating a flow
velocity of the pyrolysis gas discharged to the gas discharging
means.
25 2. The coal pyrolizing device according to claim 1, characterized
in that
the pyrolized coal discharging means is a chute, and
the gas flow-velocity regulating means includes a
partition plate which partitions a space inside the chute into
30 a portion on the inner tube side and a portion on the gas
discharging means side while allowing the pyrolysis gas to
40
be discharged to the gas discharging means side and which is
capable of adjusting a size of a horizontal cross section of
the portion on the gas discharging means side in the space
inside"the chute.
5
3. The coal pyrolizing device according to claim 2, characterized
in that the partition plate is formed of two plate bodies which
are provided on an output shaft of a motor and whose front
end portion sides are swingable in a horizontal direction by
10 an actuation the motor.
4. The coal pyrolizing device according to claim 2, characterized
in that the partition plate is formed of a plate body which
is provided on a cylinder rod of a drive cylinder and which
15 is capable of advancing toward and retreating from the inner
tube by an actuation the drive cylinder.
5. The coal pyrolizing device according to claim 2, characterized
in that the partition plate is formed of a plate body which
20 is provided on an output shaft of a motor and which has at
least one end portion side swingable relative to the inner
tube by an actuation the motor.
6. The coal pyrolizing device according to claim 5, characterized
25 in that the coal pyrolizing device comprises a plurality of
sets of the plate bodies.
7 . The coal pyrolizing device according to claim 1, characterized
in that the coal pyrolizing device further comprises:
30 gas state detecting means capable of detecting the gas flow
velocity of the pyrolysis gas discharged by the gas discharging
41
means; and
control means for controlling the gas flow-velocity
regulating means on the basis of the gas flow velocity detected
by the gas state detecting means.
5
8 . The coal pyrolizing device according to claim 2, characterized
in that
the gas flow-velocity regulating means includes
centrifuging means for separating the pyrolized coal from the
10 pyrolysis gas by centrifugation, and
the partition plate is a plate body provided in a feed pipe
configured to feed the pyrolysis gas and the pyrolized coal
from the pyrolysis discharging means to the centrifuging
means.