TECHNICAL FIELD
The present invention relates to a coal pyrolysis device
for pyrolysis of dried coal and is beneficial particularly for
refining low-rank coal (low-quality coal) that is porous and
5 contains a large amount of moisture such as brown coal and
subbituminous coal.
BACKGROUND ART
Low-rank coal (low-quality coal) containing a large amount
10 of moisture such as brown coal and subbituminous coal is low in
the amount of heat generation per unit mass. Thus, they undergo
heat treatment to be dried. In this way, the amount of heat
generation per unit mass is increased.
As a coal refinement device for refining such a low-rank
15 coal, there has been an external heating rotary kiln which is
an indirect heating pyrolysis device configured to perform
pyrolysis by indirectly heating low-rank coal with heating gas,
for example. The low-rank coal undergoes heat treatment at a stage
before the rotary kiln to become dried coal, and this dried coal
20 is fed into an inner tube. The dried coal undergoes pyrolysis
by the indirect heating to become pyrolysis coal, and this
pyrolysis coal is discharged from the inner tube.
PRIOR ART DOCUMENT
25 PATENT DOCUMENT
Patent Document 1: Japanese Patent Application Publication
No. 2003-176985
30
2
SUMMARY OF THE INVENTION
PROBLEM TO BE SOLVED BY THE INVENTION
Meanwhile, the above pyrolysis not only produces pyrolysis
gases (pyrolysis gases) such as carbon monoxide, water vapor,
5 methanol, tar from the dried coal (low-rank coal) but also
produces gases of its minor components such as mercury. The rotary
kiln has a structure in which a heating part for heating the dried
coal and a discharge part for discharging the pyrolysis coal are
distant from each other. Thus, the pyrolysis coal gets cooled
10 as it is moved toward the discharge part. The cooled pyrolysis
coal adsorbs the mercury in the pyrolysis gas. As a result, the
concentration of mercury in the pyrolysis coal per unit mass
increases.
In view of the above, the present invention has been made
15 to solve the above-mentioned problem, and an object thereof is
to provide a coal pyrolysis device capable of manufacturing
pyrolysis coal with a low mercury content.
MEANS FOR SOLVING THE PROBLEM
20 A coal pyrolysis device according to a first aspect of the
invention for solving the above-mentioned problem is a coal
pyrolysis device including a pyrolysis device main unit including
an inner tube to which dried coal is fed and an outer tube which
covers the inner tube, and configured to produce pyrolysis coal
25 and pyrolysis gas by indirectly heating the dried coal in the
inner tube with heating gas fed into the outer tube, characterized
in that the coal pyrolysis device comprises low-mercury-content
pyrolysis coal producing means for reducing adsorption of mercury
contained in the pyrolysis gas to the pyrolysis coal, or removing
30 the pyrolysis coal to which the mercury has adsorbed, to produce
the pyrolysis coal containing a small amount of the mercury.
3
A coal pyrolysis device according to a second aspect of the
invention for solving the above-mentioned problem is the coal
pyrolysis device according to the first aspect of the invention
according to the above-described invention, characterized in
5 that the low-mercury-content pyrolysis coal producing means is
a discharge pipe through which to discharge the gas in the inner
tube, and a gas inlet port of the discharge pipe is located in
the inner tube between a substantially center portion in a
longitudinal direction and an exit of a coal heating portion in
10 which the coal is heated by the heating gas.
A coal pyrolysis device according to a third aspect of the
invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the second
aspect of the invention, characterized in that the coal pyrolysis
15 device further comprises: pyrolysis coal discharging means for
discharging the pyrolysis coal; and carrier gas feeding means
for feeding carrier gas to the pyrolysis coal discharging means.
A coal pyrolysis device according to a fourth aspect of the
invention for solving the above-mentioned problem is the
20 'above-described coal pyrolysis device according to the third
aspect of the invention, characterized in that the coal pyrolysis
device further comprises heating gas delivering means for
delivering the heating gas discharged from the outer tube to the
inert gas feeding means.
25 A coal pyrolysis device according to a fifth aspect of the
invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the fourth
aspect of the invention, characterized in that the heating gas
delivering means includes: cooling means for cooling the heating
30 gas; purifying means for purifying the cooled gas cooled by the
cooling means; and a purified gas delivery pipe through which
4
to deliver the purified gas purified by the purifying means to
the inert gas feeding means.
A coal pyrolysis device according to a sixth aspect of the
invention for solving the above-mentioned problem is the
5 above-described coal pyrolysis device according to the first
aspect of the invention, characterized in that the
low-mercury-content pyrolysis coal producing means is preheating
drying means, provided at a stage before the pyrolysis device
main unit, for producing preheated dried coal by indirectly
10 heating the dried coal before being fed into the inner tube with
preheating gas.
A coal pyrolysis device according to a seventh aspect of
the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the sixth
15 aspect of the invention, characterized in that the dried coal
is heated by the preheating gas to between 280 and 350°C.
A coal pyrolysis device according to an eighth aspect of
the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the first
20 aspect of the invention, characterized in that the coal pyrolysis
device further comprises pyrolysis coal discharging means for
discharging the pyrolysis coal, and the low-mercury-content
pyrolysis coal producing means includes: a classification device
configured to classify the pyrolysis coal discharged from the
25 pyrolysis coal discharging means into coarse pyrolysis coal with
a predetermined particle size or larger and fine pyrolysis coal
with a particle size smaller than the predetermined particle
size; and fine pyrolysis coal discharging means for discharging
the fine pyrolysis coal classified by the classification device.
30 A coal pyrolysis device according to a ninth aspect of the
invention for solving the above-mentioned problem is the
5
above-described coal pyrolysis device according to the eighth
aspect of the invention, characterized in that the classification
device includes a classification plate through which the
pyrolysis coal is classified, and a through-hole in the
5 classification plate measures 0.42 mm to 2 mm.
A coal pyrolysis device according to a tenth aspect of the
invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the first
aspect of the invention, characterized in that the coal pyrolysis
10 device further comprises pyrolysis coal discharging means for
discharging the pyrolysis coal, and the low-mercury-content
pyrolysis coal producing means includes: a classification device
located between the inner tube and the pyrolysis coal discharging
means and configured to classify the pyrolysis coal discharged
15 from the inner tube into coarse pyrolysis coal with a
predetermined particle size or larger and fine pyrolysis n coal
with a particle size smaller than the predetermined particle
size; and fine pyrolysis coal discharging means for discharging
the fine pyrolysis coal classified by the classification device.
20 A coal pyrolysis device according to an eleventh third
aspect of the invention for solving the above-mentioned problem
is the above-described coal pyrolysis device according to the
first aspect of the invention, characterized in that the coal
pyrolysis device further comprises pyrolysis coal discharging
25 means for discharging the pyrolysis coal, and the
low-mercury-content pyrolysis coal producing means is a
pyrolysis coal transport acceleration device configured to
quickly transport the pyrolysis coal in the inner tube toward
the pyrolysis coal discharging means.
30 A coal pyrolysis device according to a twelfth aspect of
the invention for solving the above-mentioned problem is the
6
above-described coal pyrolysis device according to the eleventh
aspect of the invention, characterized in that a tip portion of
the pyrolysis coal transport acceleration device is located in
the vicinity of a furnace wall of the outer tube on a pyrolysis
5 coal discharge port side.
A coal pyrolysis device according to a thirteenth aspect
of the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the first
aspect of the invention, characterized in that the coal pyrolysis
10 device further comprises pyrolysis coal discharging means for
discharging the pyrolysis coal in the inner tube, the
low-mercury-content pyrolysis coal producing means is a plate
body fixed to the pyrolysis coal discharging means and extending
in a longitudinal direction of the inner tube, and the plate body
15 is located in contact with an upper portion of the pyrolysis coal.
A coal pyrolysis device according to a fourteenth aspect
of the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the
thirteenth aspect of the invention, characterized in that the
20 coal pyrolysis device further comprises inert gas feeding means
for feeding inert gas into the pyrolysis coal discharging means.
A coal pyrolysis device according to a fifteenth aspect of
the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the first
25 aspect of the invention, characterized in that the coal pyrolysis
device further comprises pyrolysis coal discharging means for
discharging the pyrolysis coal, and the low-mercury-content
pyrolysis coal producing means is a heating device provided in
the pyrolysis coal discharging means and configured to heat the
30 pyrolysis coal in the vicinity of the pyrolysis coal discharging
means.
7
A coal pyrolysis n device according to a sixteenth aspect
of the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the fifteenth
aspect of the invention, characterized in that the heating device
5 is a burner.
A coal pyrolysis device according to a sevenleenlh aspecl
of the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the fifteenth
aspect of the invention, characterized in that the heating device
10 is a heat exchange tube which is provided rotatably and in which
heating gas is capable of flowing.
A coal pyrolysis device according to an eighteenth aspect
of the invention for solving the above-mentioned problem is the
above-described coal pyrolysis device according to the first
15 aspect of the invention, characterized in that the coal pyrolysis
device further comprises pyrolysis coal discharging means for
discharging the pyrolysis coal, and the low-mercury-content
pyrolysis coal producing means is an oxidant feed device
configured to feed oxidant to the pyrolysis coal in the vicinity
20 of the pyrolysis coal discharging means.
EFFECT OF THE INVENTION
According to the coal pyrolysis devices according to the
present invention, they include the low-mercury-content
25 pyrolysis coal producing means. In this way, the adsorption of
mercury to the pyrolysis coal can be reduced, or the pyrolysis
coal having a large amount of adsorbed mercury is removed.
Accordingly, pyrolysis coal with a low mercury content can be
manufactured.
30
8
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a-schematic configuration diagram showing a first
embodiment of a coal pyrolysis device according to the present
invention.
5 Fig. 2 is a schematic configuration diagram showing a second
embodiment of the coal pyrolysis device according to the present
invention.
Fig. 3 is a schematic configuration diagram showing a third
embodiment of a pyrolysis coal manufacturing facility according
10 to the present invention.
Fig. 4 is a schematic configuration diagram showing a fourth
embodiment of the coal pyrolysis device according to the present
invention.
Fig. 54 is a schematic configuration diagram showing a fifth
15 embodiment of the coal pyrolysis device according to the present
invention.
Fig. 6 is a graph showing the relation between the particle
size of pyrolysis coal and the amount of mercury adsorption.
Fig. 7 is a schematic configuration diagram showing a sixth
20 embodiment of the coal pyrolysis device according to the present
invention.
Fig. 8 is a schematic configuration diagram showing a
seventh embodiment of the coal pyrolysis device according to the
present invention.
25 Fig. 9 is a schematic configuration diagram showing an
eighth embodiment of the coal pyrolysis device according to the
present invention.
Fig. 10 is a schematic configuration diagram showing a ninth
embodiment of the coal pyrolysis device according to the-present
30 invention.
Fig. 11 is a schematic configuration diagram showing a tenth
9
embodiment of the coal pyrolysis device according to the present
invention.
Fig. 12 is a schematic configuration diagram showing an
eleventh embodiment of the coal pyrolysis device according to
5 the present invention.
Fig. 13 is a schematic configuration diagram showing a
twelfth embodiment of the coal pyrolysis device according to the
present invention.
10 MODES FOR CARRYING OUT THE INVENTION
Modes for carrying out a coal pyrolysis device according
to the present invention will be described through embodiments.
EMBODIMENT 1
15 A coal pyrolysis device according to a first embodiment of
the present invention will be described with reference to Fig.
1.
The coal pyrolysis device according to this embodiment is
a rotary kiln and includes an indirect-heating pyrolysis device
20 main unit 111 as shown in Fig. 1. The pyrolysis device main unit
111 includes an inner tube 112, an outer tube 113 provided in
such a way as to cover the inner tube 112, and a support 114 on
which the inner tube 112 is rotatably supported. The outer tube
113 has a gas receive port (not shown) through which to receive
25 heating gas 1 and a gas discharge port (not shown) through which
to discharge heating gas 2 having heated the inner tube 112. The
section of the inner tube 112 surrounded by the outer tube 113
is a coal heating portion. The pyrolysis device main unit 111
includes a feeder 115 configured to feed dried coal 11 into the
30 inner tube 112, a separation tank 116 provided at an opening end
portion of the inner tube 112, and a hopper 117 provided to the
10
separation tank 116.
The pyrolysis n device main unit 111 further includes a
discharge pipe 101 through which to discharge gas inside the inner
tube 112 such for example as pyrolysis gas 21 to be described
5 later. The discharge pipe 101 is located along the axis of the
inner tube 112. A gas inlet port (tip portion) 101a of the
discharge pipe 101 is located in a section Dl between a
substantially center portion 112a of the inner tube 112 in the
longitudinal direction (a substantially center portion of the
10 outer tube 113 in the longitudinal direction) where the
temperature of the dried coal 11 reaches 400°C, and a coal heating
portion exit 112c of the inner tube 112 defined by a wall portion
113a of the outer tube 113. This is because if the gas inlet port
101a of the discharge pipe 101 is located at the feeder 115 side
15 of the substantially center portion 112a of the inner tube 112
(closer to a coal heating portion entrance 112b of the inner tube
112 defined by a wall portion 113b of the outer tube 113), the
pyrolyois gas 21 will contact the dried coal 11 of which the
temperature is low (the temperature is yet to be raised) , causing
20 condensation of the tar, and this tar will impair emission of
mercury from the dried coal 11. On the other hand, if the gas
inlet port 101a is located at the hopper 117 side of the wall
portion 113a of the outer tube 113 at the coal discharge side,
the pyrolysis coal 12 will adsorb the mercury in the pyrolysis
25 gas 21 when the pyrolysis coal 12 gets cooled and the pyrolysis
gas 21 contacts the cooled pyrolysis coal 12. In sum, by
positioning the gas inlet port 101a of the discharge pipe 101
within the section Dl, it is possible to more reliably prevent
contact of the gas in the inner tube 112 with the cooled pyrolysis
30 coal 12.
Note that a suction blower (not shown) or the like is coupled
11
to a base end portion of the discharge pipe 101. Thus, by sucking
the gas in the inner tube 112, in particular the pyrolysis gas
21, at a predetermined suction speed, e.g. a speed higher than
the speed -at which the coal (dried coal 11, pyrolysis coal 12)
5 is moved inside the inner tube 112, it is possible to prevent
the gas in the inner tube 112 from flowing toward the separation
tank 116 from the coal heating portion exit 112c of the inner
tube 112 and discharge the gas in the inner tube 112 to the outside
of the system. In other words, it is possible to prevent the gas
10 in the inner tube from contacting the cooled pyrolysis coal 12
and discharge the gas to the outside of the system through the
discharge pipe 101. The diameter of the discharge pipe 101 is
set to such a size that the gas in the inner tube 112 can be
discharged and the discharge pipe 101 does not contact the dried
15 coal 11 in the inner tube 112.
In this embodiment described above, the discharge pipe 101,
the suction blower, and the like serve as low-mercury-content
pyrolysis coal producing means.
The operation of the coal pyrolysis device configured as
20 above will be described below.
First, raw coal, e.g. a low-rank coal (not shown) such as
brown coal or bituminous coal is subjected to drying treatment
with a drying device (not shown) to be dried coal 11, and the
dried coal 11 is fed to the feeder 115. The feeder 115 feeds the
25 dried coal 11 into the inner tube 112 by predetermined increments.
On the other hand, heating gas 1 produced in a combustion
furnace (not shown) or the like is fed into the outer tube 113.
The heating gas 1 heats the inner tube 112, thereby indirectly
heating the dried coal 11 in the inner tube 112. As a result,
30 pyrolysis coal 12 is produced, and pyrolysis gas 21 is produced.
Note that the heating gas 1 is adjusted such that the temperature
12
of the coal (dried coal 11, pyrolysis coal 12) in the inner tube
112 reaches 400 to 450°C at the coal heating portion exit 112c.
The pyrolysis coal 12 is gradually moved inside the inner tube
112 to the separation tank 116 and is discharged from the
5 separation tank 116 to the hopper 117. The pyrolysis gas 21 is
discharged through the discharge pipe 101 to the outside of the
system. Since the gas inlet port 101a ot the discharge pipe 101
is located within the section Dl, i.e. a position where the
temperature of the coal (dried coal 11, pyrolysis coal 12) is
10 high, the pyrolysis gas 21 having a high concentration of mercury
is discharged to the outside of the system without flowing to
the vicinity of the coal heating portion exit 112c. Thus, the
pyrolysis gas 21 can be prevented from contacting the cooled coal
(dried coal 11, pyrolysis coal 12). Also, in the coal heating
15 portion exit 112c side (separation tank 116 side) of the inner
tube 112, the direction of flow of the pyrolysis gas 21 is the
opposite to the direction of movement of the coal, and the
pyrolysis gas 21 having a low concentration of mercury flows there.
Thus, adsorption of mercury to the coal can be prevented.
20 Accordingly, the pyrolysis coal 12 discharged to the hopper 117
is low in mercury content.
Subsequently, the above-described operations are repeated.
As a result, the pyrolysis coal 12 with a low mercury content
can be manufactured continuously.
25 Thus, according to the coal pyrolysis device according to
this embodiment, it includes the discharge pipe 101 with its gas
inlet port 101a located in the inner tube 112, and therefore the
pyrolysis gas 21 can be discharged without contacting the cooled
pyrolysis coal 12. Hence, it is possible to prevent adsorption
30 of the mercury in the pyrolysis gas 21 due to contact with the
cooled pyrolysis coal 12, and thereby manufacture pyrolysis coal
13
12 with a low mercury content.
EMBODIMENT 2
A coal pyrolysis device according to a second embodiment
5 of the present invention will be described with reference to Fig.
2.
This embodiment involves a configuration obtained by adding
a carrier gas feed device to the coal pyrolysis device according
to the first embodiment described above. In this embodiment, the
10 same components as those in the coal pyrolysis device according
to the first embodiment described above are denoted by the same
reference numerals.
As shown in Fig. 2, the coal pyrolysis device according to
this embodiment further includes a carrier gas feed device 121
15 serving as carrier gas feeding means. The carrier gas feed device
121 includes: a carrier gas feed device main unit 122 configured
to feed carrier gas 31 which is an inert gas (such for example
as nitrogen or combustion exhaust gas subjected to exhaust gas
treatment such as mercury removal); and a carrier gas delivery
20 pips 123 communicating with a gas delivery port of the carrier
gas feed device main unit 122 and also communicating with the
hopper 117.
The carrier gas 31 is adjusted to the temperature of the
pyrolysis coal to be discharged (e.g. 400°C to 450°C). This is
25 because if lower than 400°C, the carrier gas 31 will cool the
inner tube 112 and deteriorate the energy efficiency. On the other
hand, if higher than 450°C, the carrier gas 31 will supply thermal
energy to the pyrolysis coal 12 and accelerate the pyrolysis of
the dried coal 11. This in turn reduces the weight of the pyrolysis
30 coal and concentrates the mercury, thereby reducing its volatile
portion. As a result, pyrolysis coal with poor ignitability is
14
obtained. For this reason, the carrier gas 31 within the
above-mentioned predetermined temperature range is fed. In this
way, it is possible to prevent the pyrolysis coal 12 from being
cooled in the vicinity of the coal heating portion exit 112c inside
5 the inner tube 112, lower the concentration of mercury in the
gas, and reduce the adsorption of the mercury to the pyrolysis
coal 12.
The amount of the carrier gas 31 to be fed by the carrier
gas feed device 121 is adjusted according to the amount of the
10 gas to be sucked by the above-mentioned suction blower coupled
to the discharge pipe 101. This is because if the amount of the
carrier gas 31 to be fed is smaller than the difference between
the amount of the gas to be sucked by the suction blower and the
amount of the pyrolysis gas to be produced, the carrier gas 31
15 cannot bring about an effect of preventing contact between the
cooled pyrolysis coal 12 and the pyrolysis gas 21. On the other
hand, if the amount of the carrier gas 31 to be fed is larger
than the difference between the amount of the gas to be sucked
by the suction blower and the amount of the pyrolysis gas to be
20 produced, the amount of the carrier gas 31 inside the inner tube
112 will be so large that the production of the pyrolysis coal
12 may possibly be impaired.
In this embodiment described above, the discharge pipe.101,
the carrier gas feed device 121, and the like serve as the
25 low-mercury-content pyrolysis coal producing means.
The operation of the coal pyrolysis device configured as
above will be described below. Note that in this embodiment, like
the coal pyrolysis device according to the first embodiment
described above, the feeder 115 feeds dried coal 11 into the inner
30 tube 112 by predetermined increments, and the heating gas 1 fed
into the outer tube 113 indirectly heats the dried coal 11 in
15
the inner tube 112 to produce pyrolysis coal 12.
As the pyrolysis coal 12 is produced as described above,
pyrolysis gas 21 is produced. In this step, the carrier gas feed
device 121 is controlled to feed the carrier gas 31 into the hopper
5 117, while the suction blower is controlled according to the
amount of the pyrolysis gas 21 produced and the amount of the
carrier gas 31 fed to discharge the gases inside the inner tube
112 such as the pyrolysis gas 21 and the carrier gas 31 to the
outside of the system through the discharge pipe 101. Here, the
10 carrier gas 31 contacts the pyrolysis coal 12 and flows into the
discharge pipe 101. Hence, the pyrolysis gas 21 can be prevented
from contacting the pyrolysis coal 12 in the vicinity of the coal
heating portion exit 112c of the inner tube 112. The pyrolysis
gas 21 can be prevented from flowing into the separation tank
15 116. Thus, it is possible to prevent adsorption of the mercury
in the pyrolysis gas 21 to the pyrolysis coal 12. Accordingly,
the pyrolysis coal 12 discharged to the hopper 117 is low in
mercury content.
Subsequently, the above-described operations are repeated.
20 As a result, the pyrolysis coal 12 with a low mercury content
can be manufactured continuously.
Thus, according to the coal pyrolysis device according to
this embodiment, it includes the carrier gas feed device 121
configured to feed the carrier gas 31 into the hopper 117, and
25 the pyrolysis gas 21 can be prevented from flowing into the
separation tank 116 by feeding the carrier gas 31 into the hopper
117. As a result, it is possible to prevent adsorption of the
mercury in the pyrolysis gas 21 due to contact with the cooled
pyrolysis coal 12, and thereby more reliably manufacture
30 pyrolysis coal 12 with a low mercury content.
16
EMBODIMENT 3
A pyrolysis coal manufacturing facility according to a third
embodiment of the present invention will be described with
reference to Fig. 3.
5 This embodiment is an example of a pyrolysis coal
manufacturing facility employing the coal pyrolysis device
according to the second embodiment described above. In this
embodiment, the same components as those in the coal pyrolysis
device according to the second embodiment described above are
10 denoted by the same reference numerals.
As shown in Fig. 3, the pyrolysis coal manufacturing
facility according to this embodiment includes the
above-described pyrolysis device main unit (inner tube 112, outer
tube 113), the above-described discharge pipe 101, and the
15 above-described carrier gas feed device 121, and further includes
an indirect-heating drying device 311, a combustion furnace 321,
a cooling device 331, a granulation device 341, a heating gas
delivery device, and the like. Note that pyrolysis coal 12
produced in the pyrolysis device main unit 111 is delivered to
20 the cooling device 331. The cooling device 331 cools the pyrolysis
coal 12 to a predetermined temperature or below to obtain cooled
coal 13, and delivers the cooled coal 13 to the granulation device
341. The granulation device 341 granulates the cooled coal 13
to a predetermined size to obtain a product 14 and discharges
25 the product 14.
The indirect-heating drying device 311 includes an inner
tube 312 to which raw coal 10 is fed and an outer tube 313 provided
in such a way as to cover the inner tube 312. As heating gas 61
obtained in a later-described heat exchanger 323 is fed into the
30 outer tube 313, the heating gas 61 indirectly heats the raw coal
10 in the inner tube 312. As a result, dried coal 11 is produced,
17
and gas 51 is produced by the drying. A gas discharge port of
the inner tube 312 communicates with a gas receive port of the
later-described combustion furnace 321 through a blower 314, and
the gas 51 produced by the drying is delivered to the combustion
5 furnace 321 by the blower 314. A coal discharge porl of the inner
tube 312 communicates with a coal feed port of the inner tube
112 of the above-described pyrolysis device main unit, and the
dried coal 11 is delivered into the inner tube 112 of the pyrolysis
device main unit. Note that heating gas 62 used for heating the
10 inner tube 312 is discharged to the outside of the system.
The combustion furnace 321 includes a burner 322 and the
heat exchanger 323. A gas receive port of the burner 322
communicates with a gas discharge port of the discharge pipe 101
of the pyrolysis device main unit, and the pyrolysis gas 21 and
15 the carrier gas 31 are delivered to the burner 322. A gas discharge
port of the heat exchanger 323 communicates with a gas receive
port of the outer tube 313 of the drying device 311, and the heating
gas 61 produced in the heat exchanger 323 is delivered to the
outer tube 313 of the drying device 311. A gas discharge port
20 of the combustion furnace 321 communicates with the gas receive
port of the outer tube 113 of the pyrolysis device main unit,
and"combustion exhaust gas produced in the combustion furnace
321 is delivered as the heating gas 1 to the outer tube 113 of
the pyrolysis device main unit.
25 The gas discharge port of the outer tube 113 of the pyrolysis
device main unit communicates with a gas receive port of a vapor
generator 351 serving as cooling means through a gas delivery
pipe 361, and the heating gas 2 used for heating the inner tube
112 is delivered to the vapor generator 351. The heating gas 2
30 is cooled by the vapor generator 351 to a predetermined
temperature or below to become primary cooled gas 3. A gas
18
discharge port of the vapor generator 351 communicates with a
gas suction port of a blower 352 through a communication pipe
362. A gas discharge port of the blower 352 communicates with
a gas receive port of an exhaust gas purification device 353
5 through a delivery pipe 363. In other words, the primary cooled
gas 3 is delivered through the blower 352 to the exhaust gas
purification device 353 serving as purifying means. The exhaust
gas purification device 353 purifies the primary cooled gas 3
by removing NOx, Sox, mercury, particulate matters (PMs)
10 therefrom to thereby produce purified gas 4.
A gas discharge port of the exhaust gas purification device
353 communicates with a funnel (not shown) through a purified
gas discharge pipe 364. A flow rate adjustment valve (three-way
valve) 354 is provided at a given point along the purified gas
15 discharge pipe 364, and the flow rate adjustment valve 354
communicates with a purified gas delivery pipe 365. The purified
gas delivery pipe 365 communicates with the carrier gas delivery
pipe 123. In other words, part of the purified gas 4 is discharged
to the outside of the system through the funnel. The rest of the
20 purified gas 4 is delivered to the carrier gas delivery pipe 123
through the flow rate adjustment valve 354 and the purified gas
delivery pipe 365. Thus, the carrier gas 31 and the purified gas
4 are fed into the inner tube 112 of the pyrolysis device main
unit as carrier gas.
25 In this embodiment described above, the gas delivery pipe
361, the vapor generator 351, the communication pipe 362, the
blower 352, the delivery pipe 363, the exhaust gas purification
device 353, the purified gas discharge pipe 364, the flow rate
adjustment valve 354, the purified gas delivery pipe 365, the
30 carrier gas delivery pipe 123, and the like serve as a heating
gas delivery device which is heating gas delivering means.
19
Thus, according to the pyrolysis coal manufacturing
facility according to this embodiment, the purified gas 4
obtained by the heat exchange with and the purifying treatment
of the heating gas 2 is fed into the inner tube 112 of the pyrolysis
5 device main unit together with the carrier gas 31. Accordingly,
the energy can be saved as compared to a case where only new carrier
gas is fed.
EMBODIMENT 4
10 A coal pyrolysis device according to a fourth embodiment
of the present invention will be described with reference to Fig.
4.
This embodiment involves a configuration obtained by adding
a preheating drying device at a stage before the coal pyrolysis
15 device according to the first embodiment described above in place
of the discharge pipe provided thereto. In this embodiment, the
same components as those in the coal pyrolysis device according
to the first embodiment described above are denoted by the same
reference numerals.
20 As shown in Fig. 4, the coal pyrolysis device according to
this embodiment includes the pyrolysis device main unit 111 and
further includes a preheating drying device 131 serving as
preheating drying means provided at a stage before the pyrolysis
device main unit 111.
25 The preheating drying device 131 is a rotary kiln and
includes an inner tube 132, an outer tube 133 provided in such
a way as to cover the inner tube 132, and a support 134 on which
the inner tube 132 is rotatably supported. The outer tube 133
has a gas receive port (not shown) through which to receive
30 preheating gas 6 and a gas discharge port (not shown) through
which to discharge preheating gas 7 having heated the inner tube
20
132. The section of the inner tube 132 surrounded by the outer
tube 133 is a coal heating portion. The preheating drying device
131 includes a feeder 135 configured to feed dried coal 11 into
the inner tube 132, a separation tank 136 provided at an opening
5 . end portion of the inner tube 132, and a hopper 137 provided to
the separation tank 136. A gas discharge port 138 is provided
at an upper portion of the separation tank 136. A gas discharge
pipe 139 communicates with the gas discharge port 138.
The pyrolysis device main unit 111 includes the
10 above-mentioned inner tube 112, the above-mentioned outer tube
113, the above-mentioned support 114, the above-mentioned feeder
115, the above-mentioned separation tank 116, and the
above-mentioned hopper 117 . The separation tank 116 communicates
with a gas discharge pipe 119 through a gas discharge port 118
15 provided at an upper portion of the separation tank 116 . The feeder
115 of the pyrolysis device main unit 111 communicates with a
coal discharge port of the hopper 137 of the preheating drying
device 131, and preheated dried coal 15 is fed to the feeder 115
of the pyrolysis device main unit 111.
20 In this embodiment described above, the preheating drying
device 131 and the like serve as the low-mercury-content
pyrolysis coal producing means.
The operation of the coal pyrolysis device configured as
above will be described below.
25 First, raw coal, e.g. a low-rank coal (not shown) such as
brown coal or bituminous coal is subjected to drying treatment
with a drying device (not shown) to be dried coal 11, and the
dried coal 11 is fed to the feeder 135 of the preheating drying
device 131. The feeder 135 feeds the dried coal 11 into the inner
30 tube 132 of the preheating drying device 131 by predetermined
increments.
21
On the other hand, preheating gas 6 produced in a combustion
furnace (not shown) or the like is fed into the outer tube 133
of the preheating drying device 131. The preheating gas 6 heats
the inner tube 132, thereby indirectly heating the dried coal
5 11 in the inner tube 132. The preheating gas 6 is adjusted such
that the dried coal 11 at a coal heating portion exit 132c will
be at 280 to 350°C. As a result, preheated dried coal 15 is produced
and gas 22 is produced by the preheating. Here, when the dried
coal 11 is heated to 350°C, about 80% of the mercury in the coal
10 is emitted. Thus, the gas 22 produced by the preheating is a gas
with a high concentration of mercury. This gas 22 produced by
the preheating is discharged to the outside of the system through
the separation tank 136, the gas discharge port 138, and the gas
discharge pipe 139. The preheated dried coal 15 is gradually moved
15 inside the inner tube 132 to the separation tank 136 and is
discharged to the hopper 137.
Subsequently, the preheated dried coal 15 in the hopper 137
is delivered to the feeder 115 of the pyrolysis device main unit
111.
20 The feeder 115 of the pyrolysis device main unit 111 feeds
the preheated dried coal 15 into the inner tube 112 of the
pyrolysis device main unit 111 by predetermined increments. On
the other hand, heating gas 1 produced in a combustion furnace
(not shown) or the like is fed into the outer tube 113 of the
25 pyrolysis device main unit 111. The heating gas 1 heats the inner
tube 112, thereby indirectly heating the preheated dried coal
15 in the inner tube 112. The heating gas 1 is adjusted such that
the preheated dried coal 15 at the coal heating portion exit 112c
will be at 400 to 450°C. As a result, pyrolysis coal 16 is produced,
30 and pyrolysis gas 23 is produced. The pyrolysis coal 16 is
gradually moved inside the inner tube 112 to the separation tank
22
116 and is discharged from the separation tank 116 to the hopper
117. The pyrolysis gas 23 is discharged to the outside of the
system through the gas discharge port 118 of the separation tank
116 and the gas discharge pipe 119.
5 The above-described preheated dried coal 15 is a coal from
which the gas 22 produced by the preheating and containing a high
concentration of mercury is emitted by the preheating drying
device 131. Thus, the pyrolysis gas 23 is a gas with a lower
concentration of mercury than the gas 22 produced by the
10 preheating. For this reason, even if the coal in the inner tube
112 of the pyrolysis device main unit 111 contacts the pyrolysis
gas 23 and adsorbs the mercury in the pyrolysis gas 23 as the
coal is moved toward the hopper 117, the pyrolysis coal 16
discharged to the hopper 117 of the pyrolysis device main unit
15 111 is low in mercury content because the concentration of mercury
in the pyrolysis gas 23 is low.
Subsequently, the above-described operations are repeated.
As a result, the pyrolysis coal 16 with a low mercury content
can be manufactured continuously.
20 Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
and the preheating drying device 131 provided at a stage before
the pyrolysis device main unit 111. Also, the preheating drying
device 131 heats the dried coal 11 to such a temperature (280
25 to 350°C) that the percentage of mercury emitted therefrom will
be about 80%, to thereby let the dried coal 11 emit its mercury
and obtain the preheated dried coal 15. The pyrolysis device main
unit 111 indirectly heats the preheated dried coal 15 to obtain
the pyrolysis coal 16. In this way, the temperature of the
30 preheated dried coal 15 in the preheating drying device 131
decreases to a smaller extent than conventional cases where
23
pyrolysis coal is manufactured using one rotary kiln, and
therefore the adsorption of mercury to the coal can be reduced.
Accordingly, pyrolysis coal 16 with a low mercury content can
be obtained.
5
EMBODIMENT 5
A coal pyrolysis device according to a fifth embodiment of
the present invention will be described with reference to Figs.
5 and 6.
10 This embodiment involves a configuration obtained by adding
a classification device in place of the discharge pipe provided
to the coal pyrolysis device according to the first embodiment
described above. In this embodiment, the same components as those
in the coal pyrolysis device according to the first embodiment
15 described above are denoted by the same reference numerals.
As shown in Fig. 5, the coal pyrolysis device according to
this embodiment includes the above-described pyrolysis device
main unit 111 and further includes a classification device 141
serving as classifying means for classifying later-described
20 pyrolysis coal 12a discharged from the hopper 117.
The classification device 141 includes a classification
tank 142 and a perforated plate (classification plate) 143
provided inside the classification tank 142. The classification
tank 142 is partitioned into a main classification chamber 142a
25 and a sub classification chamber 142b by the perforated plate
143. The perforated plate 143 is located under a pyrolysis coal
receive port of the classification tank 142. The perforated plate
143 is located in such a way as to incline toward a coarse pyrolysis
coal discharge port. The perforated plate 143 has multiple
30 through-holes. The diameter of each through-hole is set to a
predetermined size, e.g. 0.42 mm to 2.0 mm.
24
The above-described classification device 141 further
includes a fine pyrolysis coal discharge pipe 144, a gas delivery
blower 145, and a gas delivery pipe 146. The fine pyrolysis coal
discharge pipe 144 communicates with a fine pyrolysis coal
5 discharge port at the bottom of the sub classification chamber
142b of the classification tank 142 and also communicates with
the gas delivery pipe 146. The gas delivery pipe 146 communicates
with a gas delivery port of the gas delivery blower 145 and also
communicates with a gas discharge pipe 119.
10 In this embodiment described above, the classification
device 141 and the like serve as the low-mercury-content
pyrolysis coal producing means . The fine pyrolysis coal discharge
pipe 144, the gas delivery blower 145, the gas delivery pipe 146,
and the like serve as fine pyrolysis coal discharging means.
15 The operation of the coal pyrolysis device configured as
above will be described below. Note that in this embodiment, like
the coal pyrolysis device according to the first embodiment
described above, the feeder 115 feeds dried coal 11 into the inner
tube 112 by predetermined increments.
20 The heating gas 1 is fed into the outer tube 113. As a result,
dried coal 11 inside the inner tube 112 is indirectly heated,
producing pyrolysis coal 12 and producing pyrolysis gas 21. The
pyrolysis coal 12 is gradually moved inside the inner tube 112
to the separation tank 116. The pyrolysis gas 21 is gradually
25 moved inside the inner tube 112 to the separation tank 116 while
contacting the pyrolysis coal 12. The pyrolysis coal 12 gets after
passing the coal heating portion exit 112c of the inner tube 112
until reaching the separation tank 116. Hence, the pyrolysis coal
12 accordingly adsorbs part of the mercury in the pyrolysis gas
30 21 and becomes mercury-adsorbed pyrolysis coal 12a. The
mercury-adsorbed pyrolysis coal 12a is discharged to the hopper
25
117. Since the mercury in the pyrolysis gas 21 adsorbs to the
pyrolysis coal 12, this gas 21 becomes low-mercury-content
pyrolysis gas 21a. The low-mercury-content pyrolysis gas 21a
flows into the gas discharge pipe 119 through the gas discharge
5 port 118.
Here, the amount of mercury adsorption to the pyrolysis coal
will be described with reference to Fig. 6 showing the relation
between the particle size of the coal (pyrolysis coal) and the
mercury content (mg/kg) . As shown in Fig. 6, it is confirmed that
10 the mercury content is 0.028 mg/kg when the particle size of the
coal is 0.42 mm or smaller, the mercury content is 0.024 mg/kg
when the particle size of the coal is 0. 42 mm to 2. 0 mm, and the
mercury content is 0.008 mg/kg when the particle size of the coal
is 2.0 mm to 3.0 mm. In other words, it is confirmed that the
15 mercury in the pyrolysis gas adsorbs preferentially to fine coal
with a small particle size and a large specific surface area.
Subsequently, the mercury-adsorbed pyrolysis coal 12a (fine
pyrolysis coal 12aa, coarse pyrolysis coal 12ab) in the hopper
117 is transferred into the classification tank 142 of the
20 classification device 141 and fed onto the perforated plate 143.
The gas delivery blower 145 delivers inert gas 32 to the gas
delivery pipe 146 at a gas flow rate that allows classification
of the mercury-adsorbed pyrolysis coal 12a. As a result, negative
pressure is generated in the sub classification chamber 142b of
25 the classification tank 142, so that the pyrolysis coal 12a is
classified through the perforated plate 143. Specifically, the
fine pyrolysis coal 12aa smaller than the through-holes of the
perforated plate 143 drops into the sub classification chamber
142b while the coarse pyrolysis coal 12ab larger than the
30 through-holes of the perforated plate 143 remains in the main
classification chamber 142a. Thus, by setting the diameter of
26
each through-hole of the perforated plate 143 to 0.42 mm, coal
with a particle size of 0.42 mm or smaller and a large amount
of adsorbed mercury can be dropped as the fine pyrolysis coal
12aa into the sub classification chamber 142b. The diameter of
5 each through-hole of the perforated plate 143 is preferably set
to 2.0 mm. In this way, coal with a particle size of 2.0 mm or
smaller and a large amount of adsorbed mercury can be dropped
as the fine pyrolysis coal 12aa into the sub classification
chamber 142b. Note that the inert gas 32 is a gas with no reactivity
10 with the fine pyrolysis coal 12aa, and nitrogen and the like are
available, for example.
The fine pyrolysis coal 12aa in the sub classification
chamber 142b is delivered to the gas discharge pipe 119 together
with the inert gas 32 through the fine pyrolysis coal discharge
15 pipe 144 and the gas delivery pipe 146. The fine pyrolysis coal
12aa is then discharged to the outside of the system together
with the inert gas 32 and the low-mercury-content pyrolysis gas
21a.
On the other hand, the coarse pyrolysis coal 12ab in the
20 main classification chamber 142a is discharged to the outside
of the system through a coarse pyrolysis coal discharge port at
the bottom of the main classification chamber 142a.
Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
25 and the classification device 141. Hence, by transferring the
pyrolysis coal 12a obtained in the pyrolysis device main unit
111 into the classification device 141, the fine pyrolysis coal
12aa with a large amount of adsorbed mercury can be classified
and removed from the mercury-adsorbed pyrolysis coal 12a in the
30 classification device 141. Accordingly, the coarse pyrolysis
coal 12ab with a small amount of adsorbed mercury can be obtained
27
as pyrolysis coal with a low mercury content.
EMBODIMENT 6
A coal pyrolysis device according to a sixth embodiment of
5 the present invention will be described with reference to Fig.
7.
This embodiment involves a configuration obtained by
changing the arrangement of the classification device provided
to the coal pyrolysis device according to the fifth embodiment
10 described above. In this embodiment, the same components as those
in the coal pyrolysis device according to the fifth embodiment
described above are denoted by the same reference numerals.
As shown in Fig. 7, the coal pyrolysis device according to
this embodiment includes the above-described pyrolysis device
15 main unit 111 and further includes a classification device 151
serving as classifying means located between the inner tube 112
and the hopper 117.
The classification device 151 includes a classification
tank 152 and a perforated plate 153 provided inside the
20 classification tank 152. The classification tank 152 is
partitioned into a main classification chamber 152a and a sub
classification chamber 152b by the perforated plate 153. The
perforated plate 153 is located under a pyrolysis coal receive
port of the classification tank 152 (the opening end portion of
25 the inner tube 112) . The perforated plate 153 is located in such
a way as to incline from the pyrolysis coal receive port toward
a coarse pyrolysis coal discharge port through which to discharge
later-described coarse pyrolysis coal 12ad in the classification
tank 152. The perforated plate 153 has multiple through-holes.
30 The diameter of each through-hole is set to a predetermined size,
e.g. 2.0 mm.
28
The above-described classification device 151 further
includes a gas delivery pipe 154, a gas delivery blower 155, and
a gas discharge pipe 157 communicating with a gas discharge port
156 of the classification tank 152. The gas delivery pipe 154
5 communicates with an inert gas receive port at the bottom of the
sub classification chamber 152b of the classification tank 152
and also communicates with a gas delivery port of the gas delivery
blower 155.
In this embodiment described above, the classification
10 device 151 and the like serve as the low-mercury-content
pyrolysis coal producing means. The gas delivery blower 155, the
gas delivery pipe 154, the perforated plate 153, the gas discharge
port 156, the gas discharge pipe 157, and the like serve as the
fine pyrolysis coal discharging means.
15 The operation of the coal pyrolysis device configured as
above will be described below. Note that in this embodiment, like
the coal pyrolysis device according to the fifth embodiment
described above, the feeder 115 feeds dried coal 11 into the inner
tube 112 by predetermined increments.
20 The heating gas 1 is fed into the outer tube 113. As a result,
dried coal 11 inside the inner tube 112 is indirectly heated,
producing pyrolysis coal 12 and producing pyrolysis gas 21. The
pyrolysis coal 12 is gradually moved inside the inner tube 112
to the classification tank 152. The pyrolysis gas 21 is gradually
25 moved inside the inner tube 112 to the classification tank 152
while contacting the pyrolysis coal 12. The pyrolysis coal 12
is cooled after passing the coal heating portion exit 112c of
the inner tube 112 until reaching the classification tank 152.
Hence, the pyrolysis coal 12 accordingly adsorbs part of the
30 mercury in the pyrolysis gas 21 and becomes mercury-adsorbed
pyrolysis coal 12a. The mercury-adsorbed pyrolysis coal 12a is
29
transferred onto the perforated plate 153 in the classification
tank 152. Since the mercury in the pyrolysis gas 21 adsorbs to
the pyrolysis coal 12, this gas 21 becomes low-mercury-content
pyrolysis gas 21a. The low-mercury-content pyrolysis gas 21a
5 flows into the gas discharge pipe 157 through the gas discharge
port 156.
Here, as described in Embodiment 5 above, the amount of
mercury adsorption to the pyrolysis coal is dependent on the
particle size of the pyrolysis coal, and the mercury in the
10 pyrolysis gas mostly adsorbs to fine pyrolysis coal 12ac with
a particle size of 2.0 mm or smaller. Note that the amount of
mercury adsorption to the coarse pyrolysis coal 12ad with a
particle size larger than 2.0 mm is smaller than that of the fine
pyrolysis coal 12ac.
15 Subsequently, the gas delivery blower 155 delivers inert
gas 33 at approximately 400°C into the classification tank 152
through the gas delivery pipe 154 at a gas flow rate that allows
classification of the mercury-adsorbed pyrolysis coal 12a. As
a result, only the fine pyrolysis coal 12ac in the
20 mercury-adsorbed pyrolysis coal 12a floats. For example, the gas
flow rate of the inert gas 33 delivered by the gas delivery blower
155 is adjusted to 7 m/s. In this case, coal with a particle size
of 2. 0 mm or smaller and a large amount of adsorbed mercury floats
as the fine pyrolysis coal 12ac. The fine pyrolysis coal 12ac
25 is then discharged to the outside of the system together with
the pyrolysis gas 21a and the inert gas 33 from the gas discharge
port 156 through the gas discharge pipe 157.
On the other hand, the coarse pyrolysis coal 12ad on the
perforated plate 153 is transferred to the hopper 117 and
30 discharged to the outside of the system.
Thus, according to the coal pyrolysis device according to
30
this embodiment, the classification device 151 is provided
between the inner tube 112 and the hopper 117. Hence, by
transferring the pyrolysis coal 12a obtained in the pyrolysis
device main unit 111 into the classification device 151, the fine
5 pyrolysis coal 12ac with a large amount of adsorbed mercury can
be classified and removed from the mercury-adsorbed pyrolysis
coal 12a in the classification device Ibl. Accordingly, the
coarse pyrolysis coal 12ad with a small amount of adsorbed mercury
can be obtained as pyrolysis coal with a low mercury content.
10
EMBODIMENT 7
A coal pyrolysis device according to a seventh embodiment
of the present invention will be described with reference to Fig.
8.
15 This embodiment involves a configuration obtained by adding
a pyrolysis coal discharge acceleration device in place of the
discharge pipe provided to the coal pyrolysis device according
to the first embodiment described above. In this embodiment, the
same components as those in the coal pyrolysis device according
20 to the first embodiment described above are denoted by the same
reference numerals.
As shown in Fig. 8, the coal pyrolysis device according to
this embodiment includes the above-described pyrolysis device
main unit 111 and further includes a pyrolysis coal transport
25 acceleration device 181. Note that the hopper 117 serves as
pyrolysis coal discharging means.
The pyrolysis coal transport acceleration device 181 is a
device configured to quickly transport the pyrolysis coal 12 in
the inner tube 112 to the hopper 117 and is a screw feeder or
30 the like, for example. A tip portion 181a of the device 181 is
positioned at the coal heating portion exit 112c of the inner
31
tube 112. Thus, the pyrolysis coal transport acceleration device
181 can shorten the period of time the pyrolysis coal 12 stays
in the section that is not heated by the heating gas 1. This can
reduce the cooling of the pyrolysis coal 12 and also shorten the
5 period of time the pyrolysis coal 12 and the pyrolysis gas 21
contact each other. As a result, it is possible to reduce the
adsorption of the mercury in the pyrolysis gas 21 to the pyrolysis
coal 12 to be discharged from the separation tank 116 to the hopper
117.
10 In this embodiment described above, the pyrolysis coal
transport acceleration device 181 and the like serve as the
low-mercury-content pyrolysis coal producing means.
Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
15 and the pyrolysis coal transport acceleration device 181, and
the pyrolysis coal 12 can be quickly transported from the coal
heating portion exit 112c of the inner tube 112 to the separation
tank 116 and discharged to the hopper 117. In this way, the
adsorption of mercury to the pyrolysis coal due to the cooling
20 of the pyrolysis coal can be reduced. Accordingly, pyrolysis coal
12 with a low mercury content can be obtained.
EMBODIMENT 8
A coal pyrolysis device according to an eighth embodiment
25 of the present invention will be described with reference to Figs.
9A and 9B.
This embodiment involves a configuration obtained by adding
a pyrolysis gas contact prevention plate body in place of the
discharge pipe provided to the coal pyrolysis device according
30 to the first embodiment described above. In this embodiment, the
same components as those in the coal pyrolysis device according
32
to the first embodiment described above are denoted by the same
reference numerals.
As shown in Figs. 9A and 9B, the coal pyrolysis device
according to this embodiment includes the above-described
5 pyrolysis device main unit 111 and further includes a pyrolysis
gas contact prevention plate body 191.
The pyrolysis gas contact prevention plate body 191 has its
base end portion fixed to a sidewall portion of the separation
tank 116 and extends in the extending direction of the inner tube
10 112. A tip portion 191a of the plate body 191 has a shape extending
in such a way as to incline obliquely upward. The plate body 191
is located in such a way as to contact an upper surface portion
12c of a pyrolysis coal layer formed by laying layers of pyrolysis
coal 12 produced in the inner tube 112. Thus, the pyrolysis coal
15 12 passes through the portion where the coal is heated by the
heating gas 1, and gets cooled until discharged to the separation
tank 116 and the hopper 117, but its contact with the pyrolysis
gas 21 is prevented by the plate body 191. The pyrolysis coal
12 is discharged from the separation tank 116 to the hopper 117.
20 In this embodiment described above, the pyrolysis gas
contact prevention plate body 191 and the like serve as the
low-mercury-content pyrolysis coal producing means.
Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
25 and the pyrolysis gas contact prevention plate body 191, and the
plate body 191 prevents the contact between the pyrolysis gas
21 and the pyrolysis coal 12 that is being cooled. In this way,
adsorption of the mercury in the pyrolysis gas 21 due to contact
with the cooled pyrolysis coal 12 can be prevented. Accordingly,
30 pyrolysis coal 12 with a low mercury content can be obtained.
33
EMBODIMENT 9
A coal pyrolysis device according to a ninth embodiment of
the present invention will be described with reference to Figs.
10A and 10B.
5 This embodiment involves a configuration obtained by adding
an inert gas feed device to the coal pyrolysis device according
to the eighth embodiment described above. In this embodiment,
the same components as those in the coal pyrolysis device
according to the eighth embodiment described above are denoted
10 by the same reference numerals.
As shown in Figs. 10A and 10B, the coal pyrolysis device
according to this embodiment includes the above-described
pyrolysis device main unit 111 and the above-described pyrolysis
gas contact prevention plate body 191 and further includes an
15 inert gas feed device 201.
The inert gas feed device 201 is provided in communication
with a gas delivery port of the hopper 117. The inert gas feed
device 201 is a device configured to feed inert gas 34 al
approximately 400°C into the hopper 117. The inert gas 34 is a
20 gas with no reactivity with the pyrolysis coal 12, and nitrogen
and the like are available, .for example. As the inert gas 34 is
fed into the hopper 117, the inert gas 34 flows between the plate
body 191 and the inner tube 112 toward the feeder 115. In this
way, the pyrolysis gas 21 can be prevented from entering the space
25 between the inner tube 112 and the plate body 191. The pyrolysis
coal 12 is discharged from the separation tank 116 to the hopper
117. Note that the inert gas 34 is discharged to the outside of
the system together with the pyrolysis gas 21 through the gas
discharge port 118 and the gas discharge pipe 119.
30 In this embodiment described above, the pyrolysis gas
contact prevention plate body 191, the inert gas feed device 201,
34
and the like serve as the low-mercury-content pyrolysis coal
producing means.
Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111,
5 the pyrolysis gas contact prevention plate body 191, and the inert
gas feed device 201, and the inert gas 34 is fed to the hopper
117 and the inert gas 34 flows between the plate body 191 and
the inner tube 112. In this way, a similar advantageous effect
to that by the coal pyrolysis device according to the eighth
10 embodiment described above can be achieved. In addition, while
the pyrolysis gas 21 is prevented from flowing into the space
between the plate body 191 and the inner tube 112, the pyrolysis
gas 21, if present between the plate body 191 and the inner tube
112, can be discharged toward the feeder 115 by the inert gas
15 34. Accordingly, pyrolysis coal 12 with a low mercury content
can be obtained more reliably.
EMBODIMENT 10
A coal pyrolysis device according to a tenth embodiment of
20 the present invention will be described with reference to Fig.
11.
This embodiment involves a configuration obtained by adding
a heating device in place of the discharge pipe provided to the
coal pyrolysis device according to the first embodiment described
25 above. In this embodiment, the same components as those in the
coal pyrolysis device according to the first embodiment described
above are denoted by the same reference numerals.
As shown in Fig. 11, the coal pyrolysis device according
to this embodiment includes the above-described pyrolysis device
30 main unit 111 and further includes a heating device 211.
The heating device 211 is a device capable of directly
35
heating the pyrolysis coal 12 and the inner tube 112 in the
vicinity of the coal heating portion exit 112c and includes a
burner 212. The temperature of the burner 212 is 1200 to 1300°C,
and the pyrolysis coal 12 is heated to and maintained at about
5 400 to 450°C. The pyrolysis coal 12 is discharged from the
separation tank 116 to the hopper 117.
In this embodiment described above, the heating device 211
and the like serve as the low-mercury-content pyrolysis coal
producing means.
10 Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
and the heating device 211, and the burner 212 provided to the
heating device 211 heats the pyrolysis coal 12 and the inner tube
112 in the vicinity of the separation tank 116. In this way, the
15 pyrolysis coal 12 does not get cooled before it is discharged
to the separation tank 116, and adsorption of the mercury in the
pyrolysis gas due to contact with cooled pyrolysis coal can be
prevented. Accordingly, pyrolysis coal 12 with a low mercury
content can be obtained.
20
EMBODIMENT 11
A coal pyrolysis device according to an eleventh embodiment
of the present invention will be described with reference to Figs.
12A and 12B.
25 This embodiment involves a configuration obtained by
changing the arrangement of the heating device provided to the
coal pyrolysis device according to the tenth embodiment described
above. In this embodiment, the same components as those in the
coal pyrolysis device according to the tenth embodiment described
30 above are denoted by the same reference numerals.
As shown in Figs. 12A and 12B, the coal pyrolysis device
36
according to this embodiment includes the above-described
pyrolysis device main unit 111 and further includes a heating
device 221.
The heating device 221 is a device capable of directly
5 heating the pyrolysis coal 12 in the vicinity of the coal heating
portion exit 112c of the inner tube 112 and is formed of a rotary
indirect heat exchange tube 222, for example. There are multiple
heat exchange tubes 222 located inside the inner tube 112 and
provided in such a way as to be rotatable about the axis of the
10 inner tube 112 in the circumferential direction thereof. A tip
portion 222a of each of the heat exchange tubes 222 is located
at the separation tank 116 side of the coal heating portion exit
112c. The heat exchange tubes 222 are fed with heating gas 8 such
for example as combustion exhaust gas or exhaust gas as gas having
15 heated a pyrolysis furnace, adjusted to a predetermined
temperature. Thus, by feeding the heating gas 8 into the heat
exchange tubes 222 and rotating the heat exchange tubes 222, the
pyrolysis coal 12 in the inner tube 112 in the vicinity of the
separation tank 116 contacts the heat exchange tubes 222 which
20 are being heated by the heating gas 8, so that the pyrolysis coal
12 contacting the heat exchange tubes 222 are directly heated.
Accordingly, the pyrolysis coal 12 is maintained at about 400
to 450°C. The pyrolysis coal 12 is discharged from the separation
tank 116 to the hopper 117. Note that heating gas 9 after heating
25 the heat exchange tubes 222 is discharged to the outside of the
system.
In this embodiment described above, the heating device 221
and the like serve as the low-mercury-content pyrolysis coal
producing means.
30 Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
37
and the heating device 221, and the heat exchange tubes 222
provided to the heating device 221 heat the pyrolysis coal 12
in the vicinity of the separation tank 116. In this way, like
the coal pyrolysis device according to the tenth embodiment
5 described above, the pyrolysis coal 12 does not get cooled before
it is discharged to the separation tank 116, and adsorption of
the mercury in the pyrolysis gas due to contact with cooled
pyrolysis coal can be prevented. Accordingly, pyrolysis coal 12
with a low mercury content can be obtained.
10
EMBODIMENT 12
A coal pyrolysis device according to a twelfth embodiment
of the present invention will be described with reference to Fig.
13.
15 This embodiment involves a configuration obtained by adding
an oxidant feed device in place of the heating device provided
to the coal pyrolysis device according to the eleventh embodiment
described above. In this embodiment, the Game components as those
. in the coal pyrolysis device according to the eleventh embodiment
20 described above are denoted by the same reference numerals.
As shown in Fig. 13, the coal pyrolysis device according
to this embodiment includes the above-described pyrolysis device
main unit 111 and further includes an oxidant feed device 231.
The oxidant feed device 231 is a device configured to feed
25 oxidant 42 to the pyrolysis coal 12 in the vicinity of the coal
heating portion exit 112c of the inner tube 112. The oxidant feed
device 231 includes a device main unit 232 serving as an oxidant
feed source and an oxidant feed pipe 233. The oxidant feed pipe
233 communicates with an oxidant discharge port of the device
30 main unit 232. The oxidant feed pipe 233 is located along the
axis of the inner tube 112. Multiple oxidant injection nozzles
38
234 are provided in the vicinity of a tip portion of the oxidant
feed pipe 233 along the longitudinal direction thereof. The
oxidant is an oxygen-containing gas (oxygen concentration: 5%
or lower) such for example as combustion exhaust gas or mixed
5 gas (air, nitrogen gas) . The oxidant is adjusted to such a
temperature, e.g. about 400 to 450°C, that it does not cool the
pyrolysis coal 12 and is capable of reacting with the pyrolysis
coal 12. Thus, when the oxidant feed device 231 feeds the oxidant
42 to the pyrolysis coal 12 in the inner tube 112 in the vicinity
10 of the coal heating portion exit 112c through the oxidant feed
pipe 233 and the oxidant injection nozzles 234, part of the
pyrolysis coal 12 and its volatile component such as tar produced
therefrom combust and generate heat, thereby heating the
pyrolysis coal 12 in the vicinity of the coal heating portion
15 exit 112c. Pyrolysis coal 12b thus heated is discharged from the
separation tank 116 to the hopper 117.
In this embodiment described above, the oxidant feed device
231 and the like serve as the low-mercury-content pyrolysis coal
producing means.
20 Thus, according to the coal pyrolysis device according to
this embodiment, it includes the pyrolysis device main unit 111
and the oxidant feed device 231, and the oxidant 42 is fed to
the pyrolysis coal 12 in the vicinity of the coal heating portion
exit 112c. In this way, the pyrolysis coal 12b heated by the
25 combustion and heat generation in the above area does not get
cooled before it is discharged to the separation tank 116, and
adsorption of the mercury in the pyrolysis gas due to contact
with cooled pyrolysis coal can be prevented. Accordingly,
pyrolysis coal 12b with a low mercury content can be obtained.
30
39
[OTHER EMBODIMENTS]
The coal pyrolysis devices including the discharge pipe 101
are described in the above first and second embodiments. Note,.
however, that coal pyrolysis devices may include a discharge pipe
5 with multiple holes provided in the peripheral surface in the
vicinity of a tip portion thereof.
INDUSTRIAL APPLICABILITY
The coal pyrolysis devices according to the present
10 invention can manufacture pyrolysis coal with a low mercury
content and can therefore be utilized significantly beneficially
in various industries.
40
WE CLAIM:
1. A coal pyrolysis device including a pyrolysis device main
unit including an inner tube to which dried coal is fed and
5 an outer tube which covers the inner tube, and configured
to produce pyrolysis coal and pyrolysis gas by indirectly
heating the dried coal in the inner tube with heating gas
fed into the outer tube, characterized in that the coal
pyrolysis device comprises low-mercury-content pyrolysis
10 coal producing means for reducing adsorption of mercury
contained in the pyrolysis gas to the pyrolysis coal, or
removing the pyrolysis coal to which the mercury has
adsorbed, to produce the pyrolysis coal containing a small
amount of the mercury.
15
2. The coal pyrolysis device according to claim 1,
characterized in that
the low mercury content pyrolysis coal producing
means is a discharge pipe through which to discharge the
20 gas in the inner tube, and
a gas inlet port of the discharge pipe is located in
the inner tube between a substantially center portion in
a longitudinal direction and an exit of a coal heating
portion in which the coal is heated by the heating gas.
25
3. The coal pyrolysis device according to claim 2,
characterized in that the coal pyrolysis device further
comprises:
pyrolysis coal discharging means for discharging the
30 pyrolysis coal; and
carrier gas feeding means for feeding carrier gas to
41
the pyrolysis coal discharging means.
4. The coal pyrolysis device according to claim 3,
characterized in that the coal pyrolysis device further
5 comprises heating gas delivering means for delivering the
heating gas discharged from the outer tube to the inert gas
feeding means.
5. The coal pyrolysis device according to claim 4,
10 characterized in that the heating gas delivering means
includes:
cooling means for cooling the heating gas;
purifying means for purifying the cooled gas cooled
by the cooling, means; and
15 a purified gas delivery pipe through which to deliver
the purified gas purified by the purifying means to the inert
gas feeding means.
6. The coal pyrolysis device according to claim 1,
20 characterized in that the low-mercury-content pyrolysis
coal producing means is preheating drying means, provided
at a stage before the pyrolysis device main unit, for
producing preheated dried coal by indirectly heating the
dried coal before being fed into the inner tube with
25 preheating gas.
7. The coal pyrolysis device according to claim 6,
characterized in that the dried coal is heated by the
preheating gas to between 280 and 350°C.
30
The coal pyrolysis device according to claim 1,
42
characterized in that
the coal pyrolysis device further comprises pyrolysis
coal discharging means for discharging the pyrolysis coal,
and
the low-mercury-conlent pyrolysis coal producing
means includes: a classification device configured to
classify the pyrolysis coal discharged from the pyrolysis
coal discharging means into coarse pyrolysis coal with a
predetermined particle size or larger and fine pyrolysis
coal with a particle size smaller than the predetermined
particle size; and fine pyrolysis coal discharging means
for discharging the fine pyrolysis coal classified by the
classification device.
The coal pyrolysis device according to claim 8,
characterized in that
the classification device includes a classification
plate for classifying the pyrolysis coal, and
a through-hole in the classification plate measures
0.42 mm to 2 mm.
The coal pyrolysis device according to claim 1,
characterized in that
the coal pyrolysis device further comprises pyrolysis
coal discharging means for discharging the pyrolysis coal,
and
the low-mercury-content pyrolysis coal producing
means includes: a classification device located between the
inner tube and the pyrolysis coal discharging means and
configured to classify the pyrolysis coal discharged from
the inner tube into coarse pyrolysis coal with a
43
predetermined particle size or larger and fine pyrolysis
coal with a particle size smaller than the predetermined
particle size; and fine pyrolysis coal discharging means
for discharging the fine pyrolysis coal classified by the
5 classification device.
11. The coal pyrolysis device according to claim 1,
characterized in that
the coal pyrolysis device further comprises pyrolysis
10 coal discharging means for discharging the pyrolysis coal,
and
the low-mercury-content pyrolysis coal producing
means is a pyrolysis coal transport acceleration device
configured to quickly transport the pyrolysis coal in the
15 inner tube toward the pyrolysis coal discharging means.
12. -The coal pyrolysis device according to claim 11,
characterized in that a tip portion of the pyrolysis coal
transport acceleration device is located in the vicinity
20 of a furnace wall of the outer tube on a pyrolysis coal
discharge port side.
13. The coal pyrolysis device according to claim 1,
characterized in that
25 the coal pyrolysis device further comprises pyrolysis
coal discharging means for discharging the pyrolysis coal
in the inner tube,
the low-mercury-content pyrolysis coal producing
means is a plate body fixed to the pyrolysis coal discharging
30 means and extending in a longitudinal direction of the inner
tube, and
44
the plate body is located in contact with an upper
portion of the pyrolysis coal.
14. The coal pyrolysis device according to claim 13,
5 characterized in that the coal pyrolysis device further
comprises inert gas feeding means for feeding inert gas into
the pyrolysis coal discharging means.
15. The coal pyrolysis device according to claim 1,
10 characterized in that
the coal pyrolysis device further comprises pyrolysis
coal discharging means for discharging the pyrolysis coal,
and
the low-mercury-content pyrolysis coal producing
15 means is a heating device provided in the pyrolysis coal
discharging means and configured to heat the pyrolysis coal
in the vicinity of the pyrolysis coal discharging means.
16. The coal pyrolysis device according to claim 15,
20 characterized in that the heating device is a burner.
17. The coal pyrolysis device according to claim 15,
characterized in that the heating device is a heat exchange
tube which is provided rotatably and in which heating gas
25 is capable of flowing.
18. The coal pyrolysis device according to claim 1,
characterized in that
the coal pyrolysis device further comprises pyrolysis
30 coal discharging means for discharging the pyrolysis coal,
and
45
10
the low-mercury-content pyrolysis coal producing
means is an oxidant feed device configured to feed oxidant
to the pyrolysis coal in the vicinity of the pyrolysis coal
discharging means.