U.S. patent application number 14/641801 was filed with the patent office on 2016-09-15 for pyrolyzed coal finisher, coal upgrade plant, and method for manufacturing deactivated pyrolyzed coal.
This patent application is currently assigned to MITSUBISHI HEAVY INDUSTRIES, LTD.. The applicant listed for this patent is MITSUBISHI HEAVY INDUSTRIES, LTD.. Invention is credited to Junji Asahara, Shintaro Honjo, Motofumi Ito, Kiyotaka Kunimune.
Application Number | 20160264894 14/641801 |
Document ID | / |
Family ID | 56879523 |
Filed Date | 2016-09-15 |
United States Patent
Application |
20160264894 |
Kind Code |
A1 |
Honjo; Shintaro ; et
al. |
September 15, 2016 |
PYROLYZED COAL FINISHER, COAL UPGRADE PLANT, AND METHOD FOR
MANUFACTURING DEACTIVATED PYROLYZED COAL
Abstract
To provide a pyrolyzed coal finisher capable of deactivating
pyrolyzed coal within a short time without causing a cost increase.
A pyrolyzed coal finisher includes: a mixer 86 that forms slurry by
mixing particulate pyrolyzed coal that is pyrolyzed coal into a
chemical solution having an oxygen blocking function after being
solidified; and a belt filter device 88 that filters the slurry
formed in the mixer 86 in a state in which each particle of the
pyrolyzed coal is coated with the chemical solution. The pyrolyzed
coal finisher further includes a chemical solution circulation path
94 that guides the chemical solution separated from the pyrolyzed
coal by the belt filter device 88 to the mixer 86.
Inventors: |
Honjo; Shintaro; (New York,
NY) ; Kunimune; Kiyotaka; (New York, NY) ;
Ito; Motofumi; (New York, NY) ; Asahara; Junji;
(New York, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MITSUBISHI HEAVY INDUSTRIES, LTD. |
Tokyo |
|
JP |
|
|
Assignee: |
MITSUBISHI HEAVY INDUSTRIES,
LTD.
Tokyo
JP
|
Family ID: |
56879523 |
Appl. No.: |
14/641801 |
Filed: |
March 9, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10L 2290/20 20130101;
C10L 5/32 20130101; C10L 2250/06 20130101; C10L 5/04 20130101; C10B
57/005 20130101; C10L 5/366 20130101; C10L 2290/547 20130101; C10L
2290/24 20130101; C10B 53/04 20130101 |
International
Class: |
C10L 5/32 20060101
C10L005/32; C10B 45/00 20060101 C10B045/00 |
Claims
1. A pyrolyzed coal finisher comprising: a mixer for forming slurry
by mixing particulate pyrolyzed coal that is pyrolyzed coal into a
chemical solution having an oxygen blocking function after being
solidified; and a filter for filtering the slurry formed in the
mixer in a state in which each particle of the pyrolyzed coal is
coated with the chemical solution.
2. The pyrolyzed coal finisher according to claim 1, further
comprising a chemical solution circulation path for guiding the
chemical solution separated from the pyrolyzed coal by the filter
to the mixer.
3. The pyrolyzed coal finisher according to claim 1, wherein the
filter is a belt filter.
4. A coal upgrade plant comprising: a pyrolyzer for pyrolyzing
coal; and a pyrolyzed coal finisher according to claim 1 that
deactivates the pyrolyzed coal pyrolyzed by the pyrolyzer.
5. A method for manufacturing deactivated pyrolyzed coal
comprising: a mixing step of forming slurry by mixing particles of
pyrolyzed coal that is pyrolyzed coal into a chemical solution
having an oxygen blocking function after being solidified; and a
filtering step of filtering the slurry formed in the mixing step in
a state in which each particle of the pyrolyzed coal is coated with
the chemical solution.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a pyrolyzed coal finisher
which deactivates pyrolyzed coal so as to avoid spontaneous
combustion, a coal upgrade plant, and a method for manufacturing
deactivated pyrolyzed coal.
[0003] 2. Description of Related Art
[0004] Since low ranking coal such as sub-bituminous coal and
lignite has a lower carbonization degree and a higher water content
than high ranking coal, a calorific value per unit weight is lower.
However, since there are abundant deposits of low ranking coal, the
low ranking coal is desired to be effectively used. Thus, various
coal upgrading techniques have been studied in which the calorific
value of the low ranking coal is increased by performing pyrolysis
after drying the low ranking coal, and upgraded coal is deactivated
so as to prevent spontaneous combustion during transportation or
storage (e.g., Japanese Unexamined Patent Application, Publication
No. 2014-31462 (hereinafter referred to as JPA 2014-31462) and PCT
International Publication No. WO 2013/103097 (hereinafter referred
to as WO 2013/103097)).
[0005] JPA 2014-31462 and WO 2013/103097 disclose that pyrolyzed
coal after pyrolysis is cooled, and oxygen is then brought into
contact with the pyrolyzed coal to oxidize the pyrolyzed coal and
thereby deactivate the surface of the pyrolyzed coal.
[0006] However, it is necessary to gradually perform the oxidation
by slowing down an oxidation rate in order to avoid the spontaneous
combustion of the pyrolyzed coal caused by rapid oxidation. Thus,
it takes an enormous amount of time to perform the deactivating
process.
[0007] Each of JPA 2014-31462 and WO 2013/103097 also discloses
that particles of the pyrolyzed coal are gathered and molded
(briquetted) into a predetermined shape so as to reduce the surface
area, and the deactivating process is performed.
[0008] However, a briquetter for briquetting the pyrolyzed coal is
required, which is one of the causes for a cost increase.
[0009] The present invention has been made in view of such
circumstances, and an object thereof is to provide a pyrolyzed coal
finisher, a coal upgrade plant, and a method for manufacturing
deactivated pyrolyzed coal capable of deactivating pyrolyzed coal
within a short time without causing a cost increase.
BRIEF SUMMARY OF THE INVENTION
[0010] To achieve the above object, a pyrolyzed coal finisher, a
coal upgrade plant, and a method for manufacturing deactivated
pyrolyzed coal of the present invention employ the following
solutions.
[0011] A pyrolyzed coal finisher according to one aspect of the
present invention includes: a mixer that forms slurry by mixing
particulate pyrolyzed coal that is pyrolyzed coal into a chemical
solution having an oxygen blocking function after being solidified;
and a filter that filters the slurry formed in the mixer in a state
in which each particle of the pyrolyzed coal is coated with the
chemical solution.
[0012] By forming the slurry of the chemical solution having the
oxygen blocking function after being solidified and the particulate
pyrolyzed coal, and filtering the slurry by the filter to coat each
particle of the pyrolyzed coal with the chemical solution,
deactivated pyrolyzed coal, each particle of which is entirely
coated with an oxygen blocking film, can be obtained. As described
above, by filtering the slurry by the filter, the deactivated
pyrolyzed coal evenly coated with the oxygen blocking film can be
mass-manufactured.
[0013] The deactivation of the pyrolyzed coal can be achieved by
coating the pyrolyzed coal with the chemical solution having the
oxygen blocking function. Thus, a deactivating equipment that
oxidizes the pyrolyzed coal gradually from the surface over time by
bringing the pyrolyzed coal into contact with oxygen or air as in
conventional cases is not required, so that the length of time
required for treatment and the costs can be reduced.
[0014] Since each particle of the pyrolyzed coal can be
deactivated, a briquetter that gathers the particulate pyrolyzed
coal and molds (briquettes) the pyrolyzed coal so as to reduce the
surface area is not required. Thus, the length of time required for
treatment and the costs can be reduced. Since the entire surface of
each particle is coated with the oxygen blocking film, the
deactivation can be more surely achieved than using a deactivating
method of briquetting the particulate pyrolyzed coal so as to
reduce the surface area.
[0015] A chemical solution obtained by dissolving a polymer such as
polyethylene oxide and starch in a solvent such as water is used as
the chemical solution having the oxygen blocking function after
being solidified. It is preferable to use a chemical solution that
is solidified at a normal temperature.
[0016] For example, the particles of the pyrolyzed coal have a
particle size of about 0.5 to 5.0 mm.
[0017] The pyrolyzed coal finisher according to one aspect of the
present invention further includes a chemical solution circulation
path that guides the chemical solution separated from the pyrolyzed
coal by the filter to the mixer.
[0018] Since the chemical solution separated from the pyrolyzed
coal by the filter is returned to the mixer to be reused, the used
amount of the chemical solution can be reduced.
[0019] In the pyrolyzed coal finisher according to one aspect of
the present invention, the filter is a belt filter.
[0020] Since the belt filter is used as the filter, continuous
treatment is enabled, so that the deactivated pyrolyzed coal can be
mass-manufactured.
[0021] A coal upgrade plant according to one aspect of the present
invention includes: a pyrolyzer that pyrolyzes coal; and the above
pyrolyzed coal finisher that deactivates the pyrolyzed coal
pyrolyzed by the pyrolyzer.
[0022] Since the above pyrolyzed coal finisher is used, deactivated
pyrolyzed coal evenly coated with an oxygen blocking film can be
obtained.
[0023] A method for manufacturing deactivated pyrolyzed coal
according to one aspect of the present invention includes: a mixing
step of forming slurry by mixing particles of pyrolyzed coal that
is pyrolyzed coal into a chemical solution having an oxygen
blocking function after being solidified; and a filtering step of
filtering the slurry formed in the mixing step in a state in which
each particle of the pyrolyzed coal is coated with the chemical
solution.
[0024] By forming the slurry of the chemical solution having the
oxygen blocking function after being solidified and the particles
of the pyrolyzed coal, and filtering the slurry by the filter to
coat each particle of the pyrolyzed coal with the chemical
solution, deactivated pyrolyzed coal, each particle of which is
entirely coated with an oxygen blocking film, can be obtained. As
described above, by filtering the slurry by the filter, the
deactivated pyrolyzed coal evenly coated with the oxygen blocking
film can be mass-manufactured.
[0025] Since the pyrolyzed coal is deactivated by filtering the
slurry of the pyrolyzed coal and the chemical solution having the
oxygen blocking function by the filter, the pyrolyzed coal can be
deactivated within a short time.
[0026] Also, since the deactivation is enabled without using a
finisher using oxidation, and a briquetter as in conventional
cases, the costs can be reduced.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0027] FIG. 1 is a schematic configuration diagram illustrating the
entire configuration of a coal upgrade plant according to one
embodiment of the present invention.
[0028] FIG. 2 is a schematic configuration diagram illustrating a
finisher shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0029] In the following, one embodiment according to the present
invention is described by reference to the drawings.
[0030] FIG. 1 shows a coal upgrade plant including a pyrolyzed coal
finisher according to one embodiment of the present invention. The
coal upgrade plant includes a dryer 1 that heats and dries coal, a
pyrolyzer 3 that heats and pyrolyzes the dried coal dried in the
dryer 1, a quencher 5 that cools the pyrolyzed coal pyrolyzed in
the pyrolyzer 3, and a pyrolyzed coal finisher (simply referred to
as "finisher" below) 7 that deactivates the pyrolyzed coal cooled
in the quencher 5.
[0031] A coal hopper 12 that receives raw coal 10 is provided on
the upstream side of the dryer 1. The raw coal is low ranking coal
such as sub-bituminous coal and lignite, and has a water content of
25 wt % or more to 60 wt % or less. The coal guided from the coal
hopper 12 is crushed to a particle size of, for example, about 20
mm or less in a crusher 14.
[0032] The coal crushed in the crusher 14 is guided to the dryer 1.
The dryer 1 is of indirect heating type using steam, and includes a
cylindrical vessel 16 that rotates about a center axis, and a
plurality of heating tubes 18 that are inserted into the
cylindrical vessel 16. The coal guided from the crusher 14 is fed
into the cylindrical vessel 16. The coal fed into the cylindrical
vessel 16 is guided from one end side (the left side in FIG. 1) to
the other end side while being agitated according to the rotation
of the cylindrical vessel 16. Steam having a temperature of
150.degree. C. or more to 200.degree. C. or less (more
specifically, 180.degree. C.), which is produced in a steam system
20, is fed into each of the heating tubes 18, thereby indirectly
heating the coal in contact with the outer periphery of each of the
heating tubes 18. The steam fed into each of the heating tubes 18
is condensed after applying condensation heat by heating the coal,
discharged from the dryer 1, and returned to the steam system
20.
[0033] A carrier gas is fed into the cylindrical vessel 16 through
a carrier gas circulation path 22. As the carrier gas, an inert gas
is used. More specifically, a nitrogen gas is used. When in
shortage, the nitrogen gas is additionally fed from a nitrogen feed
path 24 that is connected to the carrier gas circulation path 22.
The carrier gas is discharged outside of the cylindrical vessel 16
through a carrier gas discharge path 26 that is connected to the
cylindrical vessel 16 while catching a desorbed component (steam,
pulverized coal, mercury, mercury-based substances, etc.) desorbed
from the coal when passing through the cylindrical vessel 16.
[0034] A cyclone (dust collector) 28, a carrier gas cooler 30, and
a scrubber 32 are provided in the carrier gas discharge path 26
sequentially from the upstream side of a carrier gas flow
direction.
[0035] The cyclone 28 mainly removes the pulverized coal (for
example, having a particle size of 100 .mu.m or less) that is a
solid from the carrier gas by use of a centrifugal force. The
pulverized coal removed in the cyclone 28 is guided to the upstream
side of a bag filter 34 as indicated by reference character A. The
pulverized coal separated in the cyclone 28 may be also mixed into
the dried coal dried in the dryer 1.
[0036] The carrier gas cooler 30 cools the carrier gas, from which
the pulverized coal has been removed, thereby condensing steam
guided together with the carrier gas and removing the condensed
steam as drain water. The carrier gas cooler 30 is an indirect heat
exchanger. Industrial water having a normal temperature is used as
a cooling medium. Recycled water separated in a waste water
treatment equipment 40 may be also used as the cooling medium. The
drain water produced in the carrier gas cooler 30 is guided to a
liquid phase section in a lower portion of the scrubber 32.
[0037] The scrubber 32 removes the mercury and/or the mercury-based
substances (simply referred to as "mercury etc." below) from the
carrier gas, from which the pulverized coal and the steam have been
removed. Water is used as an absorber used in the scrubber 32. More
specifically, the recycled water separated in the waste water
treatment equipment 40 is used. The mercury etc. in the carrier gas
is adsorbed by the water sprayed from above the scrubber 32, and
guided to the liquid phase section in the lower portion of the
scrubber 32. In the scrubber 32, the pulverized coal that could not
be removed in the cyclone 28 is also removed.
[0038] An upstream end of the carrier gas circulation path 22 is
connected to an upper portion of the scrubber 32. A blower 36 is
provided at an intermediate position of the carrier gas circulation
path 22. The carrier gas treated in the scrubber 32 is returned to
the dryer 1 by the blower 36. Although not shown in the drawings,
one portion of the carrier gas treated in the scrubber 32 is guided
to a combustor 42.
[0039] The waste water treatment equipment 40 is connected to the
lower portion of the scrubber 32 through a waste water path 38. The
waste water treatment equipment 40 separates sludge 39, which is a
solid content such as the pulverized coal and the mercury etc., and
the recycled water by a sedimentation tank (not shown) after
aggregating and enlarging the mercury etc. by injecting a chelating
agent into waste water. The recycled water is reused in various
portions of the plant.
[0040] The coal (dried coal) dried in the dryer 1 passes through a
dried coal feed path 44 to be guided to the pyrolyzer 3 by use of
its weight. The pyrolyzer 3 is an external-heat rotary kiln, and
includes a rotating inner cylinder 46, and an outer cylinder 48
that covers the outer peripheral side of the rotating inner
cylinder 46. A nitrogen gas as a carrier gas is fed into the
rotating inner cylinder 46.
[0041] A combustion gas produced in the combustor 42 is guided to a
space between the rotating inner cylinder 46 and the outer cylinder
48 through a combustion gas introduction path 50. Accordingly, the
inside of the rotating inner cylinder 46 is maintained at
350.degree. C. or more to 450.degree. C. or less (for example,
400.degree. C.)
[0042] To the combustor 42, an air feed path 54 that guides
combustion air force-fed by a blower 52 into the combustor, a
natural gas feed path 55 that guides a natural gas as fuel into the
combustor, and a pyrolysis gas collection path 56 that collects a
pyrolysis gas generated in the pyrolyzer 3 together with the
carrier gas, and guides the gas into the combustor are connected.
In the combustor 42, a fire 51 is formed by the natural gas, the
pyrolysis gas, and the air fed into the combustor. Since the
pyrolysis gas contains a volatile content such as tar and has a
predetermined calorific value, the pyrolysis gas is used as fuel in
the combustor 42. The natural gas fed from the natural gas feed
path 55 is used for adjusting a calorific value of the fuel
injected into the combustor 42. A flow rate of the natural gas is
adjusted such that the combustion gas produced in the combustor 42
has a desired temperature.
[0043] A pyrolysis gas discharge path 58 that is used in emergency
is connected to an intermediate position of the pyrolysis gas
collection path 56. A flare stack 60 is installed on the downstream
side of the pyrolysis gas discharge path 58. A combustible
component such as tar in the pyrolysis gas is incinerated by the
flare stack 60, and a gas obtained after the incineration is
released to the atmosphere.
[0044] A combustion gas discharge path 62 through which the
combustion gas produced in the combustor is discharged is connected
to the combustor 42. An upstream end of the combustion gas
introduction path 50 that guides the combustion gas to the
pyrolyzer 3 is connected to an intermediate position of the
combustion gas discharge path 62. A first medium-pressure boiler 64
is provided in the combustion gas discharge path 62 on the
downstream side of a connection position with the combustion gas
introduction path 50.
[0045] An after-heating gas discharge path 66 through which the
combustion gas after heating the rotating inner cylinder 46 is
discharged is connected to the outer cylinder 48 of the pyrolyzer
3. A second medium-pressure boiler 68 is provided in the
after-heating gas discharge path 66. The after-heating gas
discharge path 66 is connected to the combustion gas discharge path
62 on the downstream side. A blower 70 that force-feeds the
combustion gas is provided in the combustion gas discharge path 62
on the downstream side of a connection position with the
after-heating gas discharge path 66.
[0046] The downstream side of the combustion gas discharge path 62
is connected to the bag filter 34. A flue gas, from which
combustion ash or the like is removed in the bag filter 34, is
released to the atmosphere (ATM).
[0047] The steam system 20 includes the first medium-pressure
boiler 64 and the second medium-pressure boiler 68. In the second
medium-pressure boiler 68, boiler feed water (BFW) fed thereto is
heated by the combustion gas flowing through the after-heating gas
discharge path 66, thereby producing steam. In the first
medium-pressure boiler 64, the steam produced in the second
medium-pressure boiler 68 is guided, and heated by the flue gas
flowing through the combustion gas discharge path 62, thereby
producing steam having a higher pressure. Medium-pressure steam
produced in the first medium-pressure boiler 64 and medium-pressure
steam produced in the second medium-pressure boiler 68 are
respectively stored in a steam drum (not shown), and fed to various
portions of the plant such as the heating tubes 18 of the dryer
1.
[0048] The pyrolyzed coal pyrolyzed in the pyrolyzer 3 is guided to
the quencher 5 through a pyrolyzed coal feed path 72 by use of
gravity. The quencher 5 includes a first cooler 74 that receives
the pyrolyzed coal from the pyrolyzer 3, and a second cooler 76
that receives the pyrolyzed coal cooled by the first cooler 74.
[0049] The first cooler 74 is a shell-and-tube heat exchanger, and
includes a first cylindrical vessel 78 that rotates about a center
axis, a first water spray tube 79 that is inserted into the first
cylindrical vessel 78, and a plurality of first cooling tubes 80
that are inserted into the first cylindrical vessel 78. The first
water spray tube 79 is installed in a stationary state with respect
to the rotating first cylindrical vessel 78. The pyrolyzed coal
having a temperature of 300.degree. C. or more to 500.degree. C. or
less (for example, about 400.degree. C.), which is guided from the
pyrolyzer 3, is fed into the first cylindrical vessel 78. The
pyrolyzed coal fed into the first cylindrical vessel 78 is guided
from one end side (the left side in FIG. 1) to the other end side
while being agitated according to the rotation of the first
cylindrical vessel 78.
[0050] Industrial water having a normal temperature is guided to
the first water spray tube 79. The water is sprayed on the
pyrolyzed coal and thereby brought into direct contact with the
pyrolyzed coal to cool down the pyrolyzed coal. The first water
spray tube 79 is provided on the upstream side (the left side in
FIG. 1) of the pyrolyzed coal moving within the first cylindrical
vessel 78. The recycled water separated in the waste water
treatment equipment 40 may be used as the water fed to the first
water spray tube 79.
[0051] Boiler feed water having a temperature of 50.degree. C. or
more to 100.degree. C. or less (for example, about 60.degree. C.)
is fed into each of the first cooling tubes 80, thereby indirectly
cooling the pyrolyzed coal in contact with the outer periphery of
each of the first cooling tubes 80. Each of the first cooling tubes
80 is provided on the downstream side (the right side in FIG. 1) of
the pyrolyzed coal moving within the first cylindrical vessel 78.
Each of the first cooling tubes 80 cools the pyrolyzed coal cooled
by the first water spray tube 79 to about 150.degree. C. that is
equal to or higher than a condensation temperature of water.
[0052] The second cooler 76 has substantially the same
configuration as the first cooler 74. The second cooler 76 is a
shell-and-tube heat exchanger, and includes a second cylindrical
vessel 81 that rotates about a center axis, a second water spray
tube 82 that is inserted into the second cylindrical vessel 81, and
a plurality of second cooling tubes 83 that are inserted into the
second cylindrical vessel 81. The second water spray tube 82 is
installed in a stationary state with respect to the rotating second
cylindrical vessel 81. The pyrolyzed coal cooled to about
150.degree. C. in the first cooler 74 is fed into the second
cylindrical vessel 81. The pyrolyzed coal fed into the second
cylindrical vessel 81 is guided from one end side (the left side in
FIG. 1) to the other end side while being agitated according to the
rotation of the second cylindrical vessel 81.
[0053] Industrial water having a normal temperature is guided to
the second water spray tube 82. The water is sprayed on the
pyrolyzed coal to adjust the water content of the pyrolyzed coal to
a desired value (for example, 8 wt %). The second water spray tube
82 is provided over substantially the entire second cylindrical
vessel 81 in an axial direction. The recycled water separated in
the waste water treatment equipment 40 may be used as the water fed
to the second water spray tube 82.
[0054] Industrial water having a normal temperature is guided into
each of the second cooling tubes 83, thereby indirectly cooling the
pyrolyzed coal in contact with the outer periphery of each of the
second cooling tubes 83. Each of the second cooling tubes 83 cools
the pyrolyzed coal to about 50.degree. C. The recycled water
separated in the waste water treatment equipment 40 may be used as
the water fed to each of the second cooling tubes 83.
[0055] The pyrolyzed coal cooled in the quencher 5 is guided to the
finisher 7 through a cooled pyrolyzed coal feed path 84.
[0056] As shown in FIG. 2, the finisher 7 includes a mixer 86 and a
belt filter device 88.
[0057] The pyrolyzed coal guided from the quencher 5, and a
chemical solution for performing a deactivating process are guided
to the mixer 86. The mixer 86 mixes the pyrolyzed coal and the
chemical solution by a kneader (not shown) to form slurry of the
pyrolyzed coal and the chemical solution.
[0058] The pyrolyzed coal guided to the mixer 86 has a particulate
form, and has a particle size of about 0.5 to 5.0 mm.
[0059] The chemical solution has an oxygen blocking function after
being solidified. For example, a chemical solution obtained by
dissolving a polymer such as polyethylene oxide and starch in a
solvent such as water is used. It is preferable to use a chemical
solution, such as polyethylene oxide and starch, which is
solidified at a normal temperature.
[0060] The belt filter device 88 includes an endless belt filter 90
where a mesh-like filter section is formed over substantially the
entire belt surface, and a pair of rollers 92 where the belt filter
90 is wound. The belt filter 90 has a mesh small enough not to pass
the particulate pyrolyzed coal having a particle size of, for
example, about 1 mm. A drive device (not shown) is provided in the
rollers 92. The rollers 92 are rotated about axes as indicated by
arrows in the drawing by the power of the drive device.
[0061] Although not shown in the drawings, a press that presses the
belt filter 90 from above or a suction device that sucks the belt
filter 90 from below while the belt filter 90 is running
substantially in a horizontal direction between upper ends of the
rollers 92 is provided. The slurry fed from the mixer 86 to one
upper end (the left side in the drawing) of the belt filter 90
through a slurry feed path 87 is filtered by the press or the
suction device described above while being transferred to the other
end side along with the belt filter 90 running substantially in the
horizontal direction. Accordingly, the slurry is separated into the
particulate pyrolyzed coal coated with the chemical solution over
the entire surface, and the chemical solution after passing through
the belt filter 90.
[0062] The coated particulate pyrolyzed coal separated by the belt
filter 90 is removed from the belt filter 90 by a scraper or the
like (not shown). The chemical solution is solidified at a normal
temperature, so that an oxygen blocking film is formed over the
entire surface of each particle. Deactivated pyrolyzed coal, i.e.,
final upgraded coal 104 is thereby obtained.
[0063] The chemical solution separated by the belt filter 90 is
collected from a lower portion, and transferred to the mixer 86
again through a chemical solution circulation path 94.
[0064] The following effects are produced by the present
embodiment.
[0065] By forming the slurry of the chemical solution having the
oxygen blocking function after being solidified and the particulate
pyrolyzed coal, and filtering the slurry by the belt filter 90 to
coat each particle of the particulate pyrolyzed coal with the
chemical solution, the deactivated pyrolyzed coal, each particle of
which is entirely coated with the oxygen blocking film, can be
obtained. As described above, by filtering the slurry by the belt
filter 90, the deactivated pyrolyzed coal evenly coated with the
oxygen blocking film can be mass-manufactured.
[0066] Also, the deactivation of the pyrolyzed coal can be achieved
by coating the pyrolyzed coal with the chemical solution having the
oxygen blocking function. Thus, a deactivating equipment that
oxidizes the pyrolyzed coal gradually from the surface over time by
bringing the pyrolyzed coal into contact with oxygen or air as in
conventional cases is not required, so that the length of time
required for treatment and the costs can be reduced.
[0067] Since each particle of the particulate pyrolyzed coal can be
deactivated, a briquetter that gathers the particulate pyrolyzed
coal and molds (briquettes) the pyrolyzed coal so as to reduce the
surface area is not required. Thus, the length of time required for
treatment and the costs can be reduced. Since the entire surface of
each particle is coated with the oxygen blocking film, the
deactivation can be more surely achieved than using a deactivating
method of briquetting the particulate pyrolyzed coal so as to
reduce the surface area.
[0068] Since the chemical solution separated from the pyrolyzed
coal by the belt filter device 88 is returned to the mixer 86
through the chemical solution circulation path 94 to be reused, the
used amount of the chemical solution can be reduced.
[0069] Since the belt filter 90 is used, continuous treatment is
enabled, so that the deactivated pyrolyzed coal can be
mass-manufactured. [0070] 1 Dryer [0071] 3 Pyrolyzer [0072] 5
Quencher [0073] 7 Finisher [0074] 9 Briquetter [0075] 10 Raw coal
[0076] 12 Coal hopper [0077] 14 Crusher [0078] 16 Cylindrical
vessel [0079] 18 Heating tube [0080] 20 Steam system [0081] 22
Carrier gas circulation path [0082] 28 Cyclone [0083] 30 Carrier
gas cooler [0084] 32 Scrubber [0085] 34 Bag filter [0086] 40 Waste
water treatment equipment [0087] 42 Combustor [0088] 46 Rotating
inner cylinder [0089] 48 Outer cylinder [0090] 50 Combustion gas
introduction path [0091] 74 First cooler [0092] 76 Second cooler
[0093] 78 First cylindrical vessel [0094] 79 First water spray tube
[0095] 80 First cooling tube [0096] 81 Second cylindrical vessel
[0097] 82 Second water spray tube [0098] 83 Second cooling tube
[0099] 86 Mixer [0100] 87 Slurry feed path [0101] 88 Belt filter
device [0102] 90 Belt filter [0103] 92 Roller [0104] 94 Chemical
solution circulation path [0105] 104 Upgraded coal
* * * * *