TUYERE OF MELTER-GASIFIER
Technical Field
The present invention relates to an injection tuyere of a melter-gasifier. More specifically, the present invention relates to an injection tuyere of a melter- gasifier into which various fuels or resources, including fine coals, along with oxygen in a gas or liquid state are injected during an iron making process for manufacturing molten irons from iron ores. Background Art Generally, a plurality of tuyeres are installed in an outer surface of a lower side of a melter-gasifier for manufacturing molten irons from iron ores along a circumferential direction, as part of the iron making process of an iron making plant. Oxygen and steam are injected into the melter-gasifier into which the iron ores were charged through the tuyeres. A back end of the tuyere is connected to an oxygen lance for supplying oxygen and the tuyere is also connected to a steam injection tube provided with an open/ close valve to supply steam as well as pure oxygen to the melter-gasifier.
Accordingly, the pure oxygen and the steam injected into the melter-gasifier through the oxygen lance and the steam injection tube generate a chemical reaction with a coal bed packed in the melter-gasifier, and thereby heat and a reducing gas are generated.
In this case, lumped fuels or resources are generally supplied to the melter- gasifier. However, considering the economic value of the operation, it is necessary to inject the fuels and resources in a particle or liquid state, such as fine coals, into the melter-gasifier.
Meanwhile, when molten irons are manufactured by using a blast furnace, fine coals are injected into the blast furnace through a fine coal injection tube installed in a center portion of a passage though which hot air (air with a high temperature of about 1000 "C) is passed to promote mixing of the fine coals and the hot air and to improve combustion efficiency in the blast furnace.
However, in the case that the above method is applied to a melter-gasifier into which pure oxygen is injected, a phenomenon where the tuyere is damaged can occur since the fine coals are extremely combusted in front of the tuyere. Therefore, it is difficult to inject fine coals with pure oxygen into the melter-gasifier. To solve the above problems, Korean Patent Publication No. 2002-0032674 discloses a structure for injecting fine coals and oxygen by using another passage to
inject the fine coals into the melter-gasifier through the tuyere.
In the above disclosed structure, when the fine coals are injected into the melter-gasifier through the fine coal injection tube, the fine coals are transferred through the fine coal injection tube with a quick speed (from 30m/ s to 50m/ s) by a transferring gas such as a nitrogen gas.
Meanwhile, in the above process, transferred particles of the fine coals collide with the wall of the fine coal injection tube and so the wall is continuously worn.
That is to say, the high kinetic energy of the transferred particles of the fine coals is converted into impact energy, and thereby fatigue of the injection tube is accumulated, leading eventually to the fine coal injection tube breaking.
As described above, the fine coals are directly collided with the tuyere body if the fine coal injection tube is broken. Accordingly, since the tuyere body is generally made of a material that is weak against abrasion and impact, it can be easily broken by the fine coals.
In addition, as described above, when the tuyere body is broken, cooling water circulating in the tuyere body enters into the melter-gasifier through the broken portion, and thereby an explosion in the melter-gasifier can be caused.
DISCLOSURE
Technical Problem
The present invention was contrived to solve the above problems, and an object of the present invention is to provide an injection tuyere of a melter-gasifier to prevent an explosion in the melter-gasifier that can be caused by an inflow of cooling water as described above. In addition, another object of the present invention is to prevent the tuyere body from being broken and so lengthen longevity of the injection tuyere. Technical Solution
To accomplish the above object, an injection tuyere of a melter-gasifier according to the present invention includes a tuyere body, an opening for injecting oxygen that is formed to penetrate a center portion of the tuyere body, a cooling tube that is formed in the tuyere body, a fine coal injection tube that is formed to penetrate the tuyere body away from the opening for injecting oxygen, and a protection tube that is formed to surround the fine coal injection tube. In this case, the protection tube may be extended outside of a back end of the tuyere body, a socket may be provided in an end of the protection tube, and a
guiding tube into which the fine coal injection tube is inserted may be combined with the socket.
In addition, the protection tube may be made of high carbon steel with wear resistance. In addition, the cooling tube may further include a cooling water body chamber for cooling the tuyere body, a nose cooling water supplying tube for cooling a front end of the tuyere, and a sidewall that is inserted between the cooling water body chamber and the nose cooling water supplying tube.
In this case, the sidewall may be made of copper. Advantageous Effects
In an injection tuyere of the melter-gasifier according to the present invention, when a fine coal injection tube is broken, it can be easily removed from the protection tube and so only the fine coal injection tube need be exchanged. Therefore, the injection tuyere, which has a high cost, can be used for a long time. In addition, the cooling water is prevented from entering into the melter- gasifier, and thereby the melter-gasifier can stably operate for a long time.
DESCRIPTION OF DRAWINGS
FIG. 1 is a cross-sectional view of an injection tuyere of a melter-gasifier according to an embodiment of the present invention. FIG. 2 is an end view of an injection tuyere of a melter-gasifier according to an embodiment of the present invention.
FIG. 3 is a partial cutaway cross-sectional view of an injection tuyere of a melter-gasifier according to an embodiment of the present invention.
FIG. 4 is a schematic view of an example of a melter-gasifier provided with an injection tuyere according to an embodiment of the present invention.
BEST MODE
Preferable embodiments of the present invention will be described with reference to the attached drawings in order for those skilled in the art to be able to implement it. The embodiments are merely to illustrate the present invention and the present invention is not limited thereto.
FIG. 1 is a cross-sectional view of an injection tuyere of a melter-gasifier according to an embodiment of the present invention, and FIG. 2 is an end view thereof seen from a back end 10b of an injection tuyere.
As illustrated in FIG. 1, the injection tuyere 100 according to an embodiment of the present invention includes an opening for injecting oxygen 20 formed in a center portion of the tuyere body 10, a cooling water body chamber 30, and a nose
cooling water supplying tube 40.
In addition, the injection tuyere 100 is provided with a fine coal injection tube 50 capable of supplying fuels and resources including fine coals in a fine particle or liquid state, and a protection tube 60 surrounding and protecting the fine coal injection tube 50 in the tuyere body 10.
The tuyere body 10 can be made of copper with high heat exchanging efficiency. In this case, an outer surface extended from a front end 10a of the tuyere body 10 to the inserting portion, with a length in the range of from 100mm to
150mm, can be coated with a ceramic to prevent the outer surface of the front end 10a of the tuyere body 10 arranged in the melter-gasifier from being damaged.
The fine coal injection tube 50 can be arranged by the side of the outer surface of the tuyere body 10 with a predetermined slanted angle, preferably with an angle in a range of from 7 degrees to 10 degrees with respect to a center line P of the opening for injecting oxygen 20. The protection tube 60 can be made of a material with wear resistance, such as high carbon steel, to prevent the tuyere body 10 from being broken when the fine coal injection tube 50 is worn by the fine coals.
As illustrated in FIG. 1, the protection tube 60 is formed to be protruded outside of the back end 10b of the tuyere body 10, and a socket 70 can be installed at an end portion of the protruded protection tube 60.
The socket 70 is combined with a guiding tube 80 that has an external diameter greater than an external diameter of the fine coal injection tube 50 in the back end 10b of the tuyere body 10, and thereby the fine coal injection tube 50 can be easily inserted into the tuyere body 10. In addition, as illustrated in FIG. 2, the cooling water body chamber 30 and the nose cooling water supplying tube 40 are connected to water supply tubes 30a and 40a and water drain tubes 30b and 40b, respectively, and thereby cooling water is circulated in the tuyere body 10.
The protection tube 60 has a structure to be installed to penetrate the body of the injection tuyere 100 and to avoid the cooling water body chamber 30 and the passage located in the injection tuyere 100.
FIG. 3 is a partial cutaway cross-sectional view of an injection tuyere of a melter-gasifier according to an embodiment of the present invention. As illustrated in FIG. 3, a sidewall 90 is provided between the cooling water body chamber 30 and the nose cooling water supplying tube 40.
Since the protection tube 60 is inserted into the tuyere body 10 of the
injection tuyere 100 through the above sidewall 90, the protection tube 60 is not directly exposed to the cooling water passage. The above sidewall 90 may be made of copper.
FIG. 4 is a schematic view of an example of a melter-gasifier. A plurality of injection tuyeres 100 are arranged in an external surface of a lower portion of the melter-gasifier 200 with a constant interval, and then a process for manufacturing molten irons is carried out.
In this case, oxygen and hot steam are injected through the injection tuyere 100 installed in the melter-gasifier 200 into which lumped iron ores as resources and coals as fuels are charged.
Accordingly, a combustion area is formed in front of an end portion of the injection tuyere 100, resources are melted in the combustion area, and thereby molten irons are manufactured.
In addition, as described above, resources such as fine coals are supplied through the fine coal injection tube provided in the tuyere body of each of injection tuyere 100 and the tuyere body can be protected by the protection tube even if the fine coal injection tube is broken by the high velocity impact of the fine coals.
Although exemplary embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/ or modifications of the basic inventive concept taught herein still fall within the spirit and scope of the present invention, as defined by the appended claims and their equivalents.