[Technical Field]
[0001] The present disclosure relates to a pulverized coal injecting apparatus which injects
pulverized coal into an upper portion of a bed of a melting furnace and an injecting
method thereof.
[Background Art]
[0002] Generally, a dust burner is equipment which collects iron ore dust and coal dust
generated in the melting furnace using a hot cyclone and combusts the iron ore dust
and coal dust to be reinjected into the upper portion of the bed in the melting furnace.
[0003] The dust generated in the melting furnace flows into the hot cyclone which is dust
removal equipment and then is separated by a principle of the cyclone to flow in a
lower pipe. The dust is transferred into the furnace by injection nitrogen in the
dust burner and then meets oxygen injected from the front end of the dust burner to
be combusted and reinjected into the furnace.
[0004] As described above, an amount of carbon monoxide (CO) gas which is reduced gas is
increased due to carbon combustion phenomenon at the end portion of the dust burner
and combustion heat which is generated during the combustion reaction raises a temperature
of a dome of the melting furnace.
[0005] However, there is a problem in that when an amount of dust which is reinjected into
the melting furnace is reduced or a carbon content in the dust is reduced, oxygen
is excessively injected more than a necessary oxygen amount to combust carbon in the
dust so that carbon monoxide in gas which is generated from the bed of the melting
furnace to rise is combusted and thus a content of carbon dioxide (CO2) in the reduced
gas is increased to lower ore reduction rate in a fluidizing furnace.
[0006] Further, there is a problem in that when carbon dioxide is rapidly increased within
a short time, a reduction rate is decreased to lower a molten iron temperature.
[0007] Furthermore, a dust burner which decomposes and combusts dust and dry distillation
gas generated in the melting furnace is installed in the dome of the melting furnace.
When the dust burner is located too close to the bed, there is a risk that the flame
of the dust burner hits an upper surface of the bed to be in contact therewith so
that too much dust is generated and the dust burner is damaged. Further, when the
dust burner is located too far away from the bed, there is a problem in that most
of calorie generated in the dust burner is not used to raise a temperature of the
bed, but is used to raise a temperature of the dome so that the temperature of the
dome is unnecessarily raised and an operating efficiency of the melting furnace is
deteriorated.
[DISCLOSURE]
[Technical Problem]
[0009] The present invention has been made in an effort to provide a pulverized coal injecting
apparatus of a melting furnace and an injecting method thereof which inject pulverized
coal into an upper portion of a bed of a melting furnace to enhance an ore reduction
rate while improving an oxidation degree of a reduced gas, thereby simultaneously
lowering a portion of carbon dioxide in the melting furnace and increasing a portion
of carbon monoxide.
[0010] Further, the pulverized coal injecting burner which combusts the pulverized coal
is installed between the dust burner of the melting furnace and the bed of the melting
furnace to provide calorie to the upper portion of the bed of the melting furnace
by injecting the pulverized coal and oxygen through the pulverized coal injecting
burner.
[Technical Solution]
[0011] A pulverized coal injecting apparatus of a melting furnace includes: at least one
pulverized coal injecting burner which is installed at an upper portion of a bed of
a melting furnace; at least one dust burner which is provided below the pulverized
coal injecting burner to selectively and additionally inject the pulverized coal into
the upper portion of the bed of the melting furnace; and a control unit which controls
an injecting amount of pulverized coal supplied to the pulverized coal injecting burner.
[0012] The pulverized coal injecting burner is connected to pulverized coal producing equipment
to be supplied with pulverized coal or is connected to the pulverized coal distributing
valve which is installed between the pulverized coal producing equipment and a tuyere
installed in the melting furnace to be supplied with the pulverized coal.
[0013] The dust burner may be connected to the pulverized coal producing equipment or a
pulverized coal distributing valve provided between the tuyeres provided in the melting
furnace to selectively and additionally inject the pulverized coal to the melting
furnace together with the dust.
[0014] The pulverized coal distributing valve may include a pulverized coal supply pipe
equipped with a manual valve and an orifice which adjust an injection amount of pulverized
coal.
[0015] In the pulverized coal supply pipe, a three-way valve which is remotely and automatically
controlled by the control unit may be provided.
[0016] The three-way valve may have a structure of injecting inert gas to prevent the blockage
of the pulverized coal supply pipe at the time of injecting the pulverized coal.
[0017] The pulverized coal injecting burner may further include an ejector which is provided
at a rear end thereof to insert the inert gas into the supplied pulverized coal.
[0018] The pulverized coal injecting burner may further include a cooling water pipe into
which cooling water is injected to prevent thermal damage of a front end of the pulverized
coal injecting burner.
[0019] The cooling water pipe may further include an auxiliary pipe through which the inert
gas is injected together with cooling water or independently.
[0020] The pulverized coal injecting burner may further include an inner pipe which is inserted
therein to secure a flow rate of pulverized coal to be injected.
[0021] The pulverized coal injecting burner may have a structure in which one or more oxygen
supply holes are formed therein so that the oxygen is in contact with the pulverized
coal which passes through the inner pipe.
[0022] The inner pipe may be configured such that one or more supports are provided with
an interval from an outer side of the inner pipe to be assembled.
[0023] The ejector may be configured such that a gas supply pipe is connected to a pulverized
coal inflow pipe to insert inert gas into the supplied pulverized coal.
[0024] The cooling water pipe may be configured such that a cooling water inlet pipe and
a cooling water outlet pipe connected to the pulverized coal injecting burner are
separately provided in a pipe provided in the dust burner.
[0025] A pulverized coal injecting method of a melting furnace includes: injecting pulverized
coal into an upper portion of a bed of a melting furnace using a pulverized coal injecting
burner installed in the melting furnace; and controlling an environment of injecting
the pulverized coal into the melting furnace.
[0026] The step of injecting pulverized coal and the step of controlling may further include
a pipe installing step of connecting a dust burner using a separate pipe to inject
the pulverized coal into the upper portion of the bed of the melting furnace; a pulverized
coal injecting burner installing step of installing a pulverized coal injecting burner
disposed in the same position as the dust burner above the dust burner; and a pulverized
coal injecting step of injecting the pulverized coal into the upper portion of the
bed of the melting furnace through the pipe and the pulverized coal injecting burner
installed as described above.
[0027] In the pulverized coal injecting burner installing step, the pulverized coal injecting
burner may be connected to the pulverized coal producing equipment to be supplied
with the pulverized coal or connected to a pulverized coal distributing valve which
is installed between the pulverized coal producing equipment and a tuyere installed
in the melting furnace to be supplied with the pulverized coal.
[0028] In the pulverized coal injecting burner installing step, at least one dust burner
may be installed below the pulverized coal injecting burner to selectively and additionally
inject the pulverized coal into the upper portion of the bed of the melting furnace.
[0029] In the pulverized coal injecting step, the dust burner may be connected to the pulverized
coal producing equipment or the pulverized coal distributing valve installed between
the tuyeres provided in the melting furnace to selectively and additionally inject
the pulverized coal into the melting furnace together with the dust.
[0030] In the pulverized coal injecting burner installing step, the cooling water pipe may
be installed in the pulverized coal injecting burner and an auxiliary pipe may be
connected to the cooling water pipe to prevent the injection of the pulverized coal
at the time of leaking the cooling water and inject nitrogen for back-up.
[0031] In the step of injecting pulverized coal into the upper portion of the bed of the
melting furnace, the pulverized coal may be injected by any one of processes of directly
injecting the pulverized coal into the pulverized coal injecting burner, injecting
the pulverized coal into the dust burner by splitting the pipe of the pulverized coal
injected into the tuyere installed in the melting furnace, and injecting the pulverized
coal by the dust burner through the pulverized coal injecting pipe.
[0032] In the step of injecting the pulverized coal into the upper portion of the bed of
the melting furnace, a control unit which controls an injection amount of the pulverized
coal may be installed to control the entire injection amount of the melting furnace
by controlling a rotation speed of a rotating supply device included in the pulverized
coal supply equipment to control an injection amount of the pulverized coal which
is injected into the upper portion of the bed of the melting furnace.
[0033] In the step of injecting the pulverized coal into the upper portion of the bed of
the melting furnace, whether the pulverized coal is injected to the dust burner and
an injection amount may be calculated based on a changed amount of carbon dioxide
in excess gas of the melting furnace to be measured through a flow meter.
[0034] In the meantime, a pulverized coal injecting apparatus of a melting furnace includes:
a reducing furnace which supplies reduced iron; and a melting furnace which is connected
to the reducing furnace to be charged with the reduced iron and includes a bed formed
of charged reduced iron, coal, and dried and distillated char formed therein and a
dome filled with gas above the bed in which the melting furnace includes a dust burner
which injects oxygen into the dome to decompose and combust the dust and the dried
and distillated gas generated in the melting furnace and a pulverized coal injecting
burner which injects the pulverized coal and oxygen into the melting furnace to combust
the pulverized coal.
[0035] The dust burner may be located between the bed and the dome and may be located at
a height of 2 m or higher and 3 m or lower from a surface of the bed.
[0036] A plurality of dust burners may be provided along an internal circumference of the
melting furnace.
[0037] The pulverized coal injecting burner may be located between the dust burner and the
bed.
[0038] The pulverized coal injecting burner may be located along an inner circumference
of the melting furnace so as not to overlap the dust burner.
[0039] The pulverized coal injecting burner may be located at a height of 1.3 m or higher
and 1.7 m or lower from the surface of the bed.
[0040] A ratio of oxygen injected into the dust burner and the pulverized coal injecting
burner may be 6:4 to 7:3.
[0041] When the temperature of the dome is increased to approximately 1070 degrees or higher,
the amount of oxygen injected into the dust burner may be adjusted to be reduced and
an amount of oxygen injected into the pulverized coal injecting burner may be adjusted
to be increased.
[0042] When the temperature of the dome is lowered to approximately 1030 degrees or lower,
the amount of oxygen injected into the dust burner may be adjusted to be increased
and an amount of oxygen injected into the pulverized coal injecting burner may be
adjusted to be reduced.
[0043] The pulverized coal injecting burner may inject any one fuel of pulverized coal,
liquefied natural gas, and coke oven gas to combust the pulverized coal.
[Advantageous Effects]
[0044] According to the apparatus of the exemplary embodiment of the present invention,
when pulverized coal is injected into the upper portion of the bed of the melting
furnace, an ore reduction rate of the fluidizing furnace is easily controlled by controlling
the gas oxidation degree and thus rapid repetitive fluctuation of the molten iron
temperature due to the lowering of the reduction rate may be reduced.
[0045] Further, a normal operation of the melting furnace is consistently maintained so
that a quality of the molten iron may be stabilized and a molten iron producing cost
may be saved.
[0046] Further, a pulverized coal injecting burner which injects pulverized coal and oxygen
to combust the pulverized coal is installed between the dust burner and a surface
of the bed to prevent the flame of the dust burner from hitting the upper surface
of the bed to be in contact therewith to generate the dust and the dust burner from
being damaged.
[0047] Further, the pulverized coal injecting burner is installed in an appropriate position
so that the flame of the pulverized coal injecting burner may supply sufficient calorie
to the surface of the bed without being in direct contact with the bed.
[0048] Further, an amount of oxygen injected to the dust burner at the upper portion is
reduced as much as an amount of oxygen which is injected into the pulverized coal
injecting burner, so that a supply amount to the dome may be constantly maintained.
[0049] Further, the combustion calorie generated in the pulverized coal injecting burner
is transmitted to the bed to improve the operating efficiency of the melting furnace,
thereby increasing a production amount of molten iron and reducing a ratio of a reducing
agent.
[Description of the Drawings]
[0050]
FIG. 1 is a schematic view illustrating a pulverized coal injecting apparatus of a
melting furnace according to the present exemplary embodiment.
FIG. 2 is a schematic view illustrating an arrangement state of a pulverized coal
injecting burner according to the present exemplary embodiment.
FIG. 3 is a schematic view illustrating a structure of a pulverized coal injecting
apparatus according to the present exemplary embodiment.
FIG. 4 is a schematic enlarged view illustrating an inside of a pulverized coal injecting
burner according to the present exemplary embodiment.
FIG. 5 is a schematic view illustrating an internal lance of a pulverized coal injecting
burner according to the present exemplary embodiment.
FIG. 6 is a schematic view illustrating a structure of an ejector of a pulverized
coal injecting apparatus according to the present exemplary embodiment.
FIG. 7 is a schematic view illustrating a configuration of a cooling water pipe of
a pulverized coal injecting apparatus according to the present exemplary embodiment.
FIG. 8 is a flowchart illustrating processes of a pulverized coal injecting method
according to the present exemplary embodiment.
FIG. 9 is a view schematically illustrating a pulverized coal injecting apparatus
of a melting furnace according to an exemplary embodiment of the present invention.
FIG. 10 is a view schematically illustrating a melting furnace according to an exemplary
embodiment of the present invention.
FIG. 11 is an enlarged view of a portion "A" of FIG. 2.
FIG. 12 is a top plan view schematically illustrating a melting furnace according
to an exemplary embodiment of the present invention.
FIG. 13 is a graph illustrating a temperature rising ratio of a bed of a melting furnace
according to an exemplary embodiment of the present invention by comparing with a
temperature rising ratio of the related art.
FIG. 14 is a graph illustrating a rising temperature of a bed of a melting furnace
according to an exemplary embodiment of the present invention by comparing with a
rising temperature of the related art.
FIG. 15 is a graph illustrating an effect of increasing a production amount of molten
iron of a pulverized coal injecting apparatus of a melting furnace according to an
exemplary embodiment of the present invention by comparing with that of the related
art.
FIG. 16 is a graph illustrating an effect of reducing a coal usage rate of a pulverized
coal injecting apparatus of a melting furnace according to an exemplary embodiment
of the present invention by comparing with that of the related art.
[Mode for Invention]
[0051] It should be understood that the terminology used herein is for the purpose of describing
particular exemplary embodiments only and is not intended to be limiting. It must
be noted that, as used in the specification and the appended claims, the singular
forms include plural references unless the context clearly dictates otherwise. It
will be further understood that the terms "comprises" and/or "comprising," when used
in this specification, specify the presence of stated properties, regions, integers,
steps, operations, elements, and/or components, but do not preclude the presence or
addition of one or more other properties, regions, integers, steps, operations, elements,
components, and/or groups.
[0052] The present invention will be described more fully hereinafter with reference to
the accompanying drawings, in which exemplary embodiments of the invention are shown
so as to be easily understood by the person with ordinary skill in the art. FIG. 1
is a schematic view illustrating a pulverized coal injecting apparatus of a melting
furnace according to the present exemplary embodiment.
[0053] FIG. 2 is a schematic view illustrating an arrangement state of a pulverized coal
injecting burner according to the present exemplary embodiment.
[0054] As illustrated in FIGS. 1 and 2, a pulverized coal injecting apparatus which injects
pulverized coal into an upper portion of a bed of a melting furnace includes a pulverized
coal injecting burner 20 provided at an upper portion of a dust burner 10 installed
in a melting furnace 1 to inject pulverized coal into an upper portion of a bed of
the melting furnace.
[0055] To this end, the pulverized coal injecting apparatus includes a dust burner 10, a
pulverized coal injecting burner 20, a pulverized coal distributing valve 30, and
a control unit 40.
[0056] In the present exemplary embodiment, one or more dust burners 10 are provided along
a circumferential direction of the melting furnace 1 to collect and combust the dust
to reinject the dust to the upper portion of the bed of the melting furnace 1 and
one or more pulverized coal injecting burners 20 are provided along a circumferential
direction of the melting furnace 1 at an upper portion of the dust burner 10 to inject
the pulverized coal into the upper portion of the bed of the melting furnace 1.
[0057] That is, the pulverized coal is injected to the upper portion of the bed of the melting
furnace through the pulverized coal injecting burner 20 to control a gas oxidation
degree through the injected pulverized coal and thus prevent the temperature of the
melting furnace 1 from being lowered due to the lowering of reduction rate.
[0058] A combust medium such as LNG may be selectively injected into the pulverized coal
injecting burner 20 together with the pulverized coal.
[0059] The dust burner 10 is connected to the pulverized coal distributing valve 30 through
a separate pipe to inject the pulverized coal into the upper portion of the bed of
the melting furnace.
[0060] Further, the pulverized coal distributing valve 30 is supplied with the pulverized
coal from pulverized coal producing equipment 2 to supply an appropriate amount of
pulverized coal to the pulverized coal injecting burner 20. The control unit 40 is
electrically connected to the pulverized coal distributing valve 30 to control an
amount of pulverized coal supplied to the pulverized coal injecting burner 20.
[0061] In the present exemplary embodiment, the pulverized coal injecting apparatus supplies
the pulverized coal to the pulverized coal injecting burner 20 through the pulverized
coal distributing valve 30 and controls the amount of injected pulverized coal through
the control unit 40 during the process of supplying the pulverized coal.
[0062] The pulverized coal injecting burner 20 is connected to the pulverized coal producing
equipment 2 to be supplied with the pulverized coal or is connected to the pulverized
coal distributing valve 30 which is installed between the pulverized coal producing
equipment 2 and a tuyere 50 installed in the melting furnace 1 to be supplied with
the pulverized coal.
[0063] The control unit 40 is connected to the pulverized coal producing equipment 2 and
the pulverized coal injecting burner 20 or the dust burner 10 through a connecting
line or connected to the pulverized coal distributing valve 30 between the pulverized
coal producing equipment 2 and the tuyeres 50 to control the injection of the pulverized
coal.
[0064] Further, the pulverized coal injecting apparatus further includes at least one dust
burner 10 which is provided below the pulverized coal injecting burner 20 to selectively
and additionally inject the pulverized coal into the upper portion of the bed of the
melting furnace.
[0065] The dust burner 10 may be connected to the pulverized coal producing equipment 2
or the pulverized coal distributing valve 30 provided between the tuyeres 50 provided
in the melting furnace 1 to selectively and additionally inject the pulverized coal
to the melting furnace 1 together with the dust.
[0066] Further, the pulverized coal injecting burners 20 are disposed with an interval of
90° along the circumferential direction of the melting furnace 1 to form the same
direction as the installation position of the dust burner 10 and are installed at
a height of 2.6 m to 3.2 m above the position of the dust burner 10.
[0067] As described above, the pulverized coal injecting burner 20 is installed in an optimized
position of the melting furnace 1 to effectively inject the pulverized coal to the
upper portion of the bed of the melting furnace.
[0068] In the meantime, the pulverized coal distributing valve 30 supplies the pulverized
coal and oxygen to the tuyere 50 of the melting furnace through a pipe and splits
a pipe of the pulverized coal injected to the tuyeres 50 into two branches to be connected
to the dust burner 10 so that the pulverized coal may be injected into the upper portion
of the bed of the melting furnace through the dust burner 10.
[0069] FIG. 3 is a schematic view illustrating a structure of a pulverized coal injecting
apparatus according to the present exemplary embodiment.
[0070] As illustrated in FIG. 3, the pulverized coal distributing valve 30 may include a
pulverized coal supply pipe 60 equipped with a manual valve 61 and an orifice 62 which
adjust an injection amount of pulverized coal.
[0071] The orifice 62 adjusts the injection amount of pulverized coal which is injected
into the melting furnace 1 by adjusting the amount of the pulverized coal supplied
from the pulverized coal distributing valve 30 while passing through the orifice.
[0072] Further, in the pulverized coal supply pipe 60, a three-way valve 63 which is remotely
and automatically controlled by the control unit 40 is provided. The three-way valve
63 may have a structure of injecting inert gas to prevent the blockage of the pulverized
coal supply pipe 60 at the time of injecting the pulverized coal.
[0073] The inert gas may include nitrogen.
[0074] Since the pulverized coal needs to be selectively injected only when the oxygen degree
of gas generated in the melting furnace 1 increases above a reference value, the three-way
valve 63 which is remotely and automatically controlled by the control unit 40 is
provided to inject nitrogen into the pipe when the pulverized coal is not injected.
[0075] In the present exemplary embodiment, the pulverized coal injecting burner 20 further
includes an ejector 70 which is provided at a rear end thereof to insert the inert
gas into the supplied pulverized coal and the ejector 70 discharges the nitrogen at
a high speed to prevent blockage of the pipe.
[0076] Further, the pulverized coal injecting burner 20 further includes a cooling water
pipe 80 into which the cooling water is injected to prevent thermal damage of a front
end of the pulverized coal injecting burner 20 and the cooling water pipe 80 may further
include an auxiliary pipe 81 through which the inert gas is injected together with
cooling water or independently.
[0077] That is, the cooling water pipe 80 and the auxiliary pipe 81 installed around the
pulverized coal injecting burner 20 are installed to secure the safety of the equipment.
Particularly, when the cooling water is leaked from the cooling water pipe 80, the
nitrogen may be injected to the cooling water pipe 80 through the auxiliary pipe 81
while automatically preventing the injection of the pulverized coal.
[0078] FIG. 4 is a schematic enlarged view illustrating an inside of a pulverized coal injecting
burner according to the present exemplary embodiment.
[0079] FIG. 5 is a schematic view illustrating an internal lance of a pulverized coal injecting
burner according to the present exemplary embodiment.
[0080] As illustrated in FIGS. 4 and 5, the pulverized coal injecting burner 20 may further
include an inner pipe 21 which is inserted therein to secure a flow rate of pulverized
coal to be injected. Further, one or more oxygen supply holes 22 are formed in the
pulverized coal injecting burner 20 so that the oxygen is in contact with the pulverized
coal which passes through the inner pipe 21.
[0081] Further, one or more supports are provided with an interval from an outer side of
the inner pipe 21 to be assembled so that the inner pipe 21 may be easily assembled
through the supports 23.
[0082] Here, the pulverized coal injecting burner 20 is provided with an inner pipe 21 whose
diameter is reduced so that the flow rate of the pulverized coal which passes through
the pulverized coal injecting burner 20 is increased and thus the pulverized coal
and the oxygen may be easily in contact with each other.
[0083] FIG. 6 is a schematic view illustrating a structure of an ejector of a pulverized
coal injecting apparatus according to the present exemplary embodiment.
[0084] As illustrated in FIG. 6, the ejector 70 has a structure in which a gas supply pipe
72 is connected to a pulverized coal inflow pipe 71 to insert the inert gas into the
supplied pulverized coal. The ejector supplies the nitrogen through the gas supply
pipe 72 at a high speed as if it pumps the nitrogen to prevent the blockage of the
pulverized coal inflow pipe 71 into which the pulverized coal is supplied.
[0085] FIG. 7 is a schematic view illustrating a configuration of a cooling water pipe of
a pulverized coal injecting apparatus according to the present exemplary embodiment.
[0086] As illustrated in FIG. 7, the cooling water pipe 80 has a structure in which a cooling
water inlet pipe 80A and a cooling water outlet pipe 80B connected to the pulverized
coal injecting burner 20 are separately provided in a pipe provided in the dust burner
10 so that a new cooling water pipe of the pulverized coal injecting burner 20 is
further provided in addition to the cooling water piper of the dust burner 10 which
has been previously provided.
[0087] That is, the cooling water inlet pipe 80A and the cooling water outlet pipe 80B are
provided with respect to the pulverized coal injecting burner 20 so that a cooling
water inlet pipe 80a of the dust burner 10 and the cooling water inlet pipe 80A of
the pulverized coal injecting burner 20 are connected to each other and a cooling
water outlet pipe 80b of the dust burner 10 and the cooling water outlet pipe 80B
of the pulverized coal injecting burner 20 are connected to each other.
[0088] The cooling water pipe 80 is provided to prevent the thermal damage of the front
end of the pulverized coal injecting burner 20 so that the equipment stability is
secured by injecting the cooling water.
[0089] FIG. 8 is a flowchart illustrating processes of a pulverized coal injecting method
that is an example useful for understanding the invention..
[0090] As illustrated in FIG. 8, a pulverized coal injecting method of a melting furnace
may include a step of injecting pulverized coal into an upper portion of a bed of
a melting furnace using a pulverized coal injecting burner 20 provided in the melting
furnace 1 and a step of controlling an environment of injecting the pulverized coal
into the melting furnace.
[0091] The step of injecting pulverized coal and the step of controlling may further include
a pipe installing step S1 of connecting a dust burner 10 using a separate pipe to
inject the pulverized coal into the upper portion of the bed of the melting furnace,
a pulverized coal injecting burner installing step S2 of installing a pulverized coal
injecting burner 20 disposed in the same position as the dust burner 10 above the
dust burner 10, and a pulverized coal injecting step S3 of injecting the pulverized
coal into the upper portion of the bed of the melting furnace through the pipe and
the pulverized coal injecting burner 20 installed as described above.
[0092] The pulverized coal injecting method injects the pulverized coal into the upper portion
of the bed of the melting furnace 1 and includes a process of installing a pipe in
the dust burner 10 to use the dust burner 10, a process of independently installing
the pulverized coal injecting burner 20 which injects the pulverized coal into the
melting furnace 1, and a process of selectively injecting the pulverized coal into
the upper portion of the bed of the melting furnace 1 using the dust burner 10 and
the pulverized coal injecting burner 20 installed as described above.
[0093] Further, in the pulverized coal injecting burner installing step S2, the pulverized
coal injecting burner 20 is connected to the pulverized coal producing equipment 2
to be supplied with the pulverized coal or is connected to a pulverized coal distributing
valve 30 which is installed between the pulverized coal producing equipment 2 and
a tuyere 50 installed in the melting furnace 1 to be supplied with the pulverized
coal.
[0094] In the pulverized coal injecting burner installing step S2, at least one dust burner
10 is installed below the pulverized coal injecting burner 20 to selectively and additionally
inject the pulverized coal into the upper portion of the bed of the melting furnace
1.
[0095] Further, in the pulverized coal injecting step S3, the dust burner 10 may be connected
to the pulverized coal producing equipment 2 or the pulverized coal distributing valve
30 installed between the tuyeres 50 provided in the melting furnace 1 to selectively
and additionally inject the pulverized coal into the melting furnace 1 together with
the dust.
[0096] Further, in the pipe installing step S1, a pipe of the pulverized coal injected to
the tuyeres 50 of the melting furnace 1 is split into two branches to be connected
to the dust burner 10 so that the pulverized coal may be injected through the dust
burner 10.
[0097] In the pipe installing step S1, a pulverized coal injecting pipe is installed in
the pulverized coal distributing valve 30 which supplies the pulverized coal to be
connected to the dust burner 10 so that the pulverized coal is injected through the
dust burner 10.
[0098] That is, as described above, the pulverized coal may be injected into the upper portion
of the bed of the melting furnace 1 using the dust burner 10.
[0099] Further, in the pulverized coal injecting burner installing step S2, the pulverized
coal injecting burner 20 are disposed with an interval of 90° along the circumferential
direction of the melting furnace 1 at a height of 2.6 m to 3.2 m above the position
of the dust burner 10. The pulverized coal injecting burner 20 is disposed along the
circumferential direction of the melting furnace 1 in the same position as the dust
burner 10 with a height difference above the dust burner 10.
[0100] Further, in the pulverized coal injecting burner installing step S2, the cooling
water pipe 80 is installed in the pulverized coal injecting burner 20 and an auxiliary
pipe 81 is connected to the cooling water pipe 80 to prevent the injection of the
pulverized coal at the time of leaking the cooling water and inject nitrogen for back-up.
[0101] The cooling water pipe 80 and the auxiliary pipe 81 which are installed around the
pulverized coal injecting burner 20 are installed to secure the safety of the equipment.
[0102] As described above, there are three methods for injecting pulverized coal into the
melting furnace 1.
[0103] First, in the step S3 of injecting pulverized coal into the upper portion of the
bed of the melting furnace, the pulverized coal is directly injected into the pulverized
coal injecting burner 20.
[0104] Second, the pipe of the pulverized coal injected into the tuyere 50 is split to inject
the pulverized coal into the dust burner 10.
[0105] Third, the pulverized coal is injected to the dust burner 10 through the pulverized
coal injecting pipe.
[0106] Therefore, in the method of injecting pulverized coal into the upper portion of the
bed of the melting furnace 1, the pulverized coal may be injected through any one
of three processes.
[0107] In the meantime, in the step S3 of injecting the pulverized coal into the upper portion
of the bed of the melting furnace, a control unit 40 which controls an injection amount
of the pulverized coal is installed to control the entire injection amount of the
melting furnace 1 by controlling a rotation speed of a rotating supply device included
in the pulverized coal supply equipment to control an injection amount of the pulverized
coal which is injected into the upper portion of the bed of the melting furnace.
[0108] Further, in the step S3 of injecting the pulverized coal into the upper portion of
the bed of the melting furnace, whether the pulverized coal is injected to the dust
burner 10 and an injection amount are calculated based on a changed amount of carbon
dioxide in excess gas of the melting furnace 1 to be measured through a flow meter.
[0109] Here, a gas oxidation degree and an ore reduction rate in accordance with an injection
amount of the pulverized coal of the dust burner 10 are represented in the following
Table 1.
(Table 1)
Dust Load to Hot cyclone |
Recycled Dust |
Carbon in dust |
Combustion oxygen |
Excess oxygen |
Oxygen in PCI burner |
PCI to PCI Burner (Two devices are applied) |
Lowered CO2 in gas (oxidation degree) |
Increased rate of reduction rate |
g/m3 |
t/h |
t/h |
Nm3/h |
Nm3/h |
Nm3/h |
t/h |
(t/h) /EA |
% |
% |
50 |
23 |
9 |
8,715 |
13,785 |
13.785 |
17.4 |
8.6 |
-5.9 |
9.1 |
10.500 |
13.2 |
6.6 |
-4.5 |
7.0 |
7.440 |
9.4 |
4.6 |
-3.3 |
5.0 |
4.400 |
5.6 |
2.8 |
-2.0 |
3.0 |
2.900 |
3.6 |
1.8 |
-1.3 |
2.0 |
1.500 |
1.9 |
1.0 |
-0.7 |
1.0 |
[0110] With an equipment configuration of an injection quantity of PCI Burner oxygen of
4400 Nm3/h and PC (pulverized coal) of 5.6 t/h, it is expected to increase 3.0% of
the reduction rate by lowering 2.0% of CO2 in the reduced gas.
[0111] Further, a result of installing and operating a pulverized coal injecting apparatus
in a dome of a melting furnace is represented in the following Table 2 (a reduction
rate increasing effect).
[0112] It is confirmed that only when the reduction rate is lowered below 60%, the pulverized
coal (PC) is selectively injected into the dome so that the lowering of the reduction
rate is suppressed and when 2.0% of the E/G CO2 is lowered, 3.0% of reduction rate
is increased (a design criterion is satisfied).
[0113] Accordingly, as described above, the pulverized coal is injected into the upper portion
of the bed of the melting furnace 1 to block combustion of carbon monoxide gas due
to excessive oxygen and an amount of generated carbon monoxide gas is increased to
drastically lower the oxidation degree of the reduced gas and thus increase the ore
reduction rate of the fluidizing furnace.
[0114] Further, when the oxidation degree is rapidly increased, the injection amount of
the pulverized coal is increased to supplement a content of carbon monoxide, thereby
constantly maintaining the oxidation degree.
[0115] In the meantime, referring to FIG. 9, the pulverized coal injecting apparatus of
a melting furnace includes a reducing furnace 7 and a melting furnace 1. In addition
to this, the pulverized coal injecting apparatus of a melting furnace may further
include other devices as needed. Iron ore is charged in the reducing furnace 7 to
be reduced. The iron ore which is charged in the reducing furnace 7 is dried in advance
and then produced as reduced iron while passing through the reducing furnace 7. The
reducing furnace 7 is a packed bed type reducing furnace and is supplied with reduced
gas from the melting furnace 1 to form a packed bed therein.
[0116] The melting furnace 1 is connected to the reducing furnace 7 to be supplied with
reduced iron produced in the reducing furnace 7 and charged with coal briquette or
coal produced in a coal briquette producing apparatus. The reduced iron and coal charged
into the melting furnace 1 and dried and distillated char form a bed 3 in the melting
furnace 1.
[0117] A dome 9 is formed in an upper portion of the melting furnace 1. The dome 9 is formed
above the bed 3 and has a broader space than other parts of the melting furnace 1.
In the dome, a reduced gas with a high temperature exists.
[0118] The coal briquette is charged into the dome 9 of the melting furnace 1 and then rapidly
heated to fall down to a lower portion of the melting furnace 1. The char generated
by thermal decomposition reaction of the coal briquette moves to the lower portion
of the melting furnace 1 to exothermically react with oxygen supplied through the
tuyere 50. As a result, the coal briquette may be used as a heat source which maintains
the melting furnace 1 at a high temperature. In the meantime, since the char provides
permeability, a large amount of gas generated in the lower portion of the melting
furnace 1 and reduced iron supplied from the reducing furnace 7 may easily and uniformly
pass through the bed 3 in the melting furnace 1.
[0119] In addition to the above-described coal briquette, bulk cinder or cokes may be charged
in the melting furnace 1 as needed. The tuyere 50 is installed on an outer wall of
the melting furnace 1 to inject oxygen. The oxygen is injected into the bed 3 to form
a combustion zone 8. The coal briquette is combusted in the combustion zone 8 to generate
reduced gas.
[0120] The melting furnace 1 includes a dust burner 10 and a pulverized coal injecting burner
20. The dust burner 10 injects oxygen into the dome 9 to decompose and combust the
dust and the dried and distillated gas generated in the melting furnace 1. The dust
burner 10 is located between the bed 3 and the dome 9. A plurality of dust burners
may be provided along an internal circumference of the melting furnace 1.
[0121] The dust burner 10 may be installed with a predetermined distance from an upper surface
of the bed 3, that is, at a height of approximately 2 m or higher and approximately
3 m or lower. When the dust burner 10 is located to be too close to the bed 3, the
flame of the dust burner 10 hits the upper surface of the bed 3 to be in contact therewith
so that dust is excessively generated and a risk of damaging the dust burner 10 is
increased.
[0122] In order to avoid the above-mentioned risk, the dust burner 10 is located to be approximately
2 m or higher and approximately 3 m or lower from the surface of the bed 3. In this
case, most of the calorie generated in the dust burner 10 is not used to raise the
temperature of the bed 3 but is used to raise the temperature of the dome 8 so that
the temperature of the dome 9 is unnecessarily increased and the operating efficiency
of the melting furnace 1 may be deteriorated. In order to prevent the above-described
problem, the pulverized coal injecting burner 20 is located between the dust burner
10 and the bed 3.
[0123] The pulverized coal injecting burner 20 may be located at a height of approximately
1.3 m or higher and approximately 1.7 m or lower from the surface of the bed 3. The
pulverized coal injecting burner 20 is located such that the flame of the pulverized
coal injecting burner 20 supplies sufficient calorie to the surface of the bed 3 without
being in direct contact with the bed 3. When the pulverized coal injecting burner
20 is too far away from the surface of the bed 3, heat is not effectively supplied
to the bed 3. In contrast, when the pulverized coal injecting burner 20 is too close
to the surface of the bed 3, the pulverized coal injecting burner 20 may be broken.
[0124] FIG. 11 is an enlarged view of a portion A of FIG. 2. The pulverized coal injecting
burner 20 injects pulverized coal 5 and oxygen 6 into the melting furnace 1 to combust
the pulverized coal 5. In this case, combustion heat generated in the pulverized coal
injecting burner 20 by combustion flame 11 is transmitted to the bed 3 to raise the
temperature of the bed 3.
[0125] In the meantime, the pulverized coal injecting burner 20 injects any one fuel of
pulverized coal, liquefied natural gas, and coke oven gas to combust the pulverized
coal.
[0126] FIG. 12 is a top plan view schematically illustrating a melting furnace that is an
example useful for understanding the invention. A plurality of dust burners 10 may
be provided along an inner circumference of the melting furnace 1 and as illustrated
in FIG. 12, four dust burners 10 may be installed in the dome 9. Further, the pulverized
coal injecting burner 20 may be located along the inner circumference of the melting
furnace 1 so as not to overlap the dust burner 10. That is, the pulverized coal injecting
burner 20 may be located between dust burners 10 in a circumferential direction and
four pulverized coal injecting burners 20 may be provided. When the pulverized coal
injecting burners 20 are not located between dust burners 10, the dust burner 10 located
above the pulverized coal injecting burner 20 may be damaged due to the combustion
flame of the pulverized coal injecting burner 20.
[0127] In the meantime, the ratio of oxygen which is injected to the dust burner 10 and
the pulverized coal injecting burner 20 is approximately 6:4 to approximately 7:3.
When oxygen which is injected into the pulverized coal injecting burner 20 is too
much, an amount of oxygen which is injected into the dust burner 10 is too small,
so that volatile matter generated from the dust and coal in the dome 9 may not be
sufficiently combusted or decomposed. In contrast, when an amount of oxygen injected
into the pulverized coal injecting burner 20 is too small, a size of the combustion
flame is reduced so that an effect of raising a temperature of the bed 3 is lowered.
[0128] The oxygen injection ratio of the pulverized coal injecting burner 20 is managed
with respect to a temperature of the dome 9. When the temperature of the dome 9 is
increased to approximately 1070 degrees or higher, the amount of oxygen of the dust
burner 10 is reduced and an amount of oxygen of the pulverized coal injecting burner
20 is increased so that more combustion heat generated in the pulverized coal injecting
burner 20 flows to the bed 3.
[0129] In contrast, when the temperature of the dome 9 is lowered to approximately 1030
degrees or lower, the amount of oxygen of the pulverized coal injecting burner 20
is reduced and an amount of oxygen of the dust burner 10 is increased so that the
combustion heat generated in the dust burner 10 raises a temperature of a gas of the
dome 9.
[0130] FIG. 13 is a graph illustrating a temperature rising ratio of a bed of a melting
furnace by comparing with a temperature rising ratio of the related art, FIG. 14 is
a graph illustrating a rising temperature of a bed of a melting furnace by comparing
with a rising temperature of the related art, FIG. 15 is a graph illustrating an effect
of increasing a production amount of molten iron of a pulverized coal injecting apparatus
of a melting furnace by comparing with that of the related art, and FIG. 16 is a graph
illustrating an effect of reducing a coal usage rate of a pulverized coal injecting
apparatus of a melting furnace by comparing with that of the related art.
[0131] In order to prove the effect of the present invention, an interval between the dust
burner 10 and the bed 3 of the melting furnace 1 is lowered from 3 m of the related
art to 1.5 m to carry out a practical simulation test operation. As a result, as illustrated
in FIG. 13, it is confirmed that a ratio of heat which raises a temperature of the
dome 9, of the combustion heat generated in the dust burner 10 and the pulverized
coal injecting burner 20, is reduced but a ratio of heat which raises the temperature
of the bed 3 is increased from approximately 22% of the related art to approximately
31%. As a result, as illustrated in FIG. 14, the temperature of the bed 3 is increased
from approximately 210 degrees of the related art to approximately 340 degrees.
[0132] A temperature rising effect of the bed 3 improves an operation performance. Therefore,
it is understood that as illustrated in FIG. 15, a daily molten iron production amount
is increased from approximately 5200 ton of the related art to approximately 5500
ton and as illustrated in FIG. 16, a coal usage ratio (fuel ratio) is lowered from
approximately 860 kg/t-p of the related art to approximately 820 kg/t-p.
[0133] As described above, in the exemplary embodiment of the present invention, the pulverized
coal injecting burner which injects pulverized coal and oxygen to combust the pulverized
coal is provided between the dust burner and the surface of the bed to prevent the
flame of the dust burner from hitting the upper surface of the bed to be in contact
therewith to generate the dust and the dust burner from being damaged.
[0134] Further, the pulverized coal injecting burner is installed in an appropriate location
so that the flame of the pulverized coal injecting burner may supply sufficient calorie
to the surface of the bed without being in direct contact with the bed.
[0135] Furthermore, an amount of oxygen injected to the upper dust burner is reduced as
much as an amount of oxygen which is injected into the pulverized coal injecting burner,
so that a supply amount to the dome may be constantly maintained.
[0136] Further, the combust calorie generated in the pulverized coal injecting burner is
transmitted to the bed to improve the operating efficiency of the melting furnace,
thereby increasing a production amount of molten iron and reducing a ratio of reducing
agent.
[Industrial Applicability]
[0137] According to the apparatus of the exemplary embodiment of the present invention,
when pulverized coal is injected into the upper portion of the bed of the melting
furnace, an ore reduction rate of the fluidizing furnace is easily controlled by controlling
the gas oxidation degree and thus rapid repetitive fluctuation of the molten iron
temperature due to the lowering of the reduction rate may be reduced.
[0138] Further, a normal operation of the melting furnace is consistently maintained so
that a quality of the molten iron may be stabilized and a molten iron producing cost
may be saved.
1. Kohlenstaub-Einspritzvorrichtung eines Schmelzofens (1), wobei die Kohlenstaub-Einspritzvorrichtung
Folgendes umfasst:
mindestens einen Kohlenstaub-Einspritzbrenner (20), der an einem oberen Abschnitt
eines Bettes eines Schmelzofens (1) installiert ist;
eine Steuereinheit, die eine Einspritzmenge des Kohlenstaubs steuert, die dem Kohlenstaub-Einspritzbrenner
zugeführt wird; und
mindestens einen Staubbrenner, der unter dem Kohlenstaub-Einspritzbrenner bereitgestellt
ist, um den Kohlenstaub selektiv und zusätzlich in den oberen Abschnitt des Bettes
des Schmelzofens einzuspritzen,
wobei der Kohlenstaub-Einspritzbrenner (20) mit der Kohlenstaub-Erzeugungsausrüstung
(2) verbunden ist, der Kohlenstaub zuzuführen ist, oder mit einem Kohlenstaub-Wegeventil
(30) verbunden ist, das zwischen der Kohlenstaub-Erzeugungsausrüstung (2) und einer
Düse (50) installiert ist, die in dem Schmelzofen (1) installiert ist, dem der Kohlenstaub
zuzuführen ist,
dadurch gekennzeichnet, dass der mindestens eine Kohlenstaub-Einspritzbrenner (20) an einem oberen Abschnitt des
mindestens einen Staubbrenners (10) bereitgestellt ist.
2. Kohlenstaub-Einspritzvorrichtung nach Anspruch 1, wobei der Staubbrenner (10) mit
der Kohlenstaub-Erzeugungsausrüstung (2) oder einem Kohlenstaub-Wegeventil (30) verbunden
ist, das zwischen den Düsen (50) bereitgestellt ist, die in dem Schmelzofen (1) bereitgestellt
sind, um den Kohlenstaub selektiv und zusätzlich zusammen mit dem Staub in den Schmelzofen
(1) einzuspritzen.
3. Kohlenstaub-Einspritzvorrichtung nach Anspruch 2, wobei das Kohlenstaub-Wegeventil
(30) ein Kohlenstaub-Zufuhrrohr (60) beinhaltet, das mit einem Handventil (61) und
einer Öffnung (62) ausgestattet ist, die dazu ausgelegt sind, eine Einspritzung des
Kohlenstaubs einzustellen.
4. Kohlenstaub-Einspritzvorrichtung nach Anspruch 3, wobei in dem Kohlenstaub-Zufuhrrohr
(60) ein Dreiwegeventil (63), das von der Steuereinheit (40) aus der Ferne und automatisch
gesteuert wird, bereitgestellt ist.
5. Kohlenstaub-Einspritzvorrichtung nach Anspruch 4, wobei das Dreiwegeventil (63) eine
Struktur für das Einspritzen von inertem Gas zum Zeitpunkt des Einspritzens des Kohlenstaubs
aufweist und dazu ausgelegt ist, die Blockierung des Kohlenstaub-Zufuhrrohrs zu verhindern.
6. Kohlenstaub-Einspritzvorrichtung nach Anspruch 1, wobei der Kohlenstaub-Einspritzbrenner
(20) ferner eine Ausstoßvorrichtung (70) beinhaltet, die an einem hinteren Ende davon
bereitgestellt ist, um ein inertes Gas in den zugeführten Kohlenstaub einzuführen.
7. Kohlenstaub-Einspritzvorrichtung nach Anspruch 1, wobei der Kohlenstaub-Einspritzbrenner
(20) ferner ein Kühlwasserrohr (80) beinhaltet, in welches Kühlwasser eingespritzt
wird, um eine thermische Schädigung eines vorderen Endes des Kohlenstaub-Einspritzbrenners
(20) zu verhindern.
8. Kohlenstaub-Einspritzvorrichtung nach Anspruch 7, wobei das Kühlwasserrohr (80) ferner
ein Hilfsrohr (81) beinhaltet, durch welches das inerte Gas zusammen mit dem Kühlwasser
oder unabhängig eingespritzt wird.
9. Kohlenstaub-Einspritzvorrichtung nach Anspruch 1, wobei der Kohlenstaub-Einspritzbrenner
(20) ferner ein inneres Rohr (21) beinhaltet, das darin eingeführt ist, um eine Durchflussrate
von einzuspritzendem Kohlenstaub sicherzustellen.
10. Kohlenstaub-Einspritzvorrichtung nach Anspruch 9, wobei der Kohlenstaub-Einspritzbrenner
(20) eine Struktur aufweist, in der ein oder mehrere Sauerstoffzufuhrlöcher (22) darin
gebildet sind, sodass der Sauerstoff mit dem Kohlenstaub in Berührung ist, der durch
das innere Rohr (21) gelangt.
11. Kohlenstaub-Einspritzvorrichtung nach Anspruch 9, wobei das innere Rohr (21) derart
konfiguriert ist, dass eine oder mehrere Stützen (23) mit einem Abstand von einer
äußeren Seite des inneren Rohrs (21), das anzubringen ist, bereitgestellt sind.
12. Kohlenstaub-Einspritzvorrichtung nach Anspruch 6, wobei die Ausstoßvorrichtung (70)
derart konfiguriert ist, dass ein Gaszufuhrrohr (72) mit einem Kohlenstaub-Zulaufrohr
(71) verbunden ist, um inertes Gas in den zugeführten Kohlenstaub einzuführen.
13. Kohlenstaub-Einspritzvorrichtung nach Anspruch 7, wobei das Kühlwasserrohr (80) derart
konfiguriert ist, dass ein Kühlwassereinlassrohr (80A) und ein Kühlwasserauslassrohr
(80B), die mit dem Kohlenstaub-Einspritzbrenner (20) verbunden sind, separat in einem
Rohr bereitgestellt sind, welches in dem Staubbrenner (10) bereitgestellt ist.
1. Appareil d'injection de charbon pulvérisé d'un four de fusion (1), l'appareil d'injection
de charbon pulvérisé comprenant :
au moins un brûleur d'injection de charbon pulvérisé (20) qui est installé au niveau
d'une portion supérieure d'un lit d'un four de fusion (1) ;
une unité de commande qui commande une quantité d'injection de charbon pulvérisé fournie
au brûleur d'injection de charbon pulvérisé ; et
au moins un brûleur de poussière qui est prévu sous le brûleur d'injection de charbon
pulvérisé pour injecter de manière sélective et additionnelle le charbon pulvérisé
dans la portion supérieure du lit du four de fusion,
dans lequel le brûleur d'injection de charbon pulvérisé (20) est raccordé à un équipement
de production de charbon pulvérisé (2) qui doit être alimenté en charbon pulvérisé
ou est raccordé à une vanne de distribution de charbon pulvérisé (30) qui est installée
entre l'équipement de production de charbon pulvérisé (2) et une tuyère (50) installée
dans le four de fusion (1) qui doit être alimenté en charbon pulvérisé,
caractérisé en ce que l'au moins un brûleur d'injection de charbon pulvérisé (20) est prévu au niveau d'une
portion supérieure de l'au moins un brûleur de poussière (10).
2. Appareil d'injection de charbon pulvérisé selon la revendication 1, dans lequel le
brûleur de poussière (10) est raccordé à l'équipement de production de charbon pulvérisé
(2) ou à une vanne de distribution de charbon pulvérisé (30) prévue entre les tuyères
(50) fournies dans le four de fusion (1) pour injecter de manière sélective et additionnelle
le charbon pulvérisé dans le four de fusion (1) conjointement à la poussière.
3. Appareil d'injection de charbon pulvérisé selon la revendication 2, dans lequel la
vanne de distribution de charbon pulvérisé (30) comporte un tuyau d'alimentation en
charbon pulvérisé (60) équipé d'une vanne manuelle (61) et d'un orifice (62) qui sont
adaptés pour ajuster une injection de charbon pulvérisé.
4. Appareil d'injection de charbon pulvérisé selon la revendication 3, dans lequel dans
le tuyau d'alimentation en charbon pulvérisé (60), une vanne à trois voies (63) qui
est commandée à distance et automatiquement par l'unité de commande (40) est prévue.
5. Appareil d'injection de charbon pulvérisé selon la revendication 4, dans lequel la
vanne à trois voies (63) présente une structure d'injection de gaz inerte au moment
de l'injection du charbon pulvérisé et est adaptée pour empêcher l'obstruction du
tuyau d'alimentation en charbon pulvérisé.
6. Appareil d'injection de charbon pulvérisé selon la revendication 1, dans lequel le
brûleur d'injection de charbon pulvérisé (20) comporte en outre un éjecteur (70) qui
est prévu à une extrémité arrière de celui-ci pour insérer un gaz inerte dans le charbon
pulvérisé fourni.
7. Appareil d'injection de charbon pulvérisé selon la revendication 1, dans lequel le
brûleur d'injection de charbon pulvérisé (20) comporte en outre un tuyau d'eau de
refroidissement (80) dans lequel de l'eau de refroidissement est injectée pour empêcher
un endommagement thermique d'une extrémité avant du brûleur d'injection de charbon
pulvérisé (20).
8. Appareil d'injection de charbon pulvérisé selon la revendication 7, dans lequel le
tuyau d'eau de refroidissement (80) comporte en outre un tuyau auxiliaire (81) par
lequel le gaz inerte est injecté conjointement à de l'eau de refroidissement ou indépendamment.
9. Appareil d'injection de charbon pulvérisé selon la revendication 1, dans lequel le
brûleur d'injection de charbon pulvérisé (20) comporte en outre un tuyau interne (21)
qui est inséré dans celui-ci pour assurer un débit de charbon pulvérisé qui doit être
injecté.
10. Appareil d'injection de charbon pulvérisé selon la revendication 9, dans lequel le
brûleur d'injection de charbon pulvérisé (20) présente une structure dans laquelle
un ou plusieurs orifices d'alimentation en oxygène (22) sont formés dans celui-ci
de sorte que l'oxygène soit en contact avec le charbon pulvérisé qui passe par le
tuyau interne (21).
11. Appareil d'injection de charbon pulvérisé selon la revendication 9, dans lequel le
tuyau interne (21) est configuré de sorte qu'un ou plusieurs supports (23) soient
prévus avec un intervalle depuis un côté externe du tuyau interne (21) pour être assemblés.
12. Appareil d'injection de charbon pulvérisé selon la revendication 6, dans lequel l'éjecteur
(70) est configuré de sorte qu'un tuyau d'alimentation en gaz (72) soit raccordé à
un tuyau d'entrée de charbon pulvérisé (71) pour insérer un gaz inerte dans le charbon
pulvérisé fourni.
13. Appareil d'injection de charbon pulvérisé selon la revendication 7, dans lequel le
tuyau d'eau de refroidissement (80) est configuré de sorte qu'un tuyau d'entrée d'eau
de refroidissement (80A) et qu'un tuyau de sortie d'eau de refroidissement (80B) raccordés
au brûleur d'injection de charbon pulvérisé (20) soient prévus séparément dans un
tuyau prévu dans le brûleur de poussière (10).