KR200447331Y1 - Device for Reducing Coal Spillage of Bowl Mill - Google Patents

Abstract

The present invention relates to a coal spill reduction device of a bowl mill.

The present invention is coupled to the upper side of the air control ring provided on the lower side of the bowl extending ring and the upper side of the outer circumference of the bowl extension ring, the vertical surface is formed in the vertical direction of the air control ring, the upper end of the vertical surface is inclined in the inner bowl direction An end weir having a first inclined surface formed thereon, and having an upper end of the first inclined surface inclined in a lower bowl extending ring direction and having a second inclined surface coupled to the upper bowl extending ring; And a radially flat plate shape at a lower outer circumferential surface of the air control ring, the one end of which is connected to the upper end of the vane wheel blade, and coupled to the upper end of the vane wheel blade. And a tip plate formed in a wedge shape inclined with a bowl.

According to the present invention, in a bowl grinding machine in which coal is pulverized into pulverized coal, the speed of the air passing through the air passage and the vortex are prevented to prevent the pulverized coal particles from falling to the bottom of the bowl, It is effective to smooth the transfer.

Thermal power plant, coal grinding, bowl grinding, pulverized coal, pyrite

Description

Device for Reducing Coal Spillage of Bowl Mill

The present invention relates to a coal spill reduction device of a bowl mill. More specifically, in a bowl grinding machine in which coal is pulverized into pulverized coal, the speed of air passing through the air passage and prevention of vortex prevents pulverized coal particles from falling to the bottom of the bowl while simultaneously The present invention relates to a coal outflow abatement device for a bowl mill that does not impede transportation.

In general, coal-fired power plants employ a method of crushing coal into fine particles and burning them in a boiler. The equipment for pulverizing coal into pulverized coals suitable for combustion is called a powderizer or a mill, which includes a tube powder, a bowl powder, a ball powder, a roller powder, and a non-pulverized powder. Eater Wheel Differentiation.

Bowl mills are most commonly used in coal-fired power plants and cogeneration plants due to their reliability, low power consumption and relatively quiet operating noise.

1 is a view showing a schematic configuration of a conventional bowl differentiator.

Bowl mills include bowls (102), grinding rollers (108), bowl drives (not shown), roller compactors (112), lubricant systems, air seal systems, and pulverized coal separators (124). Is done.

The grinding roller 108 is rotated by the journal 110, which is pressed by the roller pressing device 112 to the grinding table 106. In FIG. 1, the hydraulic device is illustrated as the roller pressing device 112. In some cases, a spring device may be used. A plurality of such grinding rollers 108 are provided in the bowl differentiator, and typically three grinding rollers 108 are arranged at equal intervals, but only one grinding roller 108 is illustrated in FIG. 1.

The coal supplied from the feeder (not shown) falls through the coal supply pipe 114 to the center of the bowl 102 and is pushed in the circumferential direction of the grinding table 106 by the centrifugal force of the bowl 102. Grinding is performed between the grinding table 106 and the grinding roller 108 at the top.

The pulverized coal is raised to the top of the bowl 102 by the rising air supplied below the bowl 102, and the large particles of coal are dropped onto the bowl 102 to be crushed again. The small particles of coal collide with the air by hitting the deflector blades 126 of the classifier 124 located at the top of the pulverizer. According to this turning angle and speed, finely divided fine coal is separated and falls on the bowl 102. The opening degree of the deflector blade 126 can be adjusted outside the differentiator.

Finally, at the outlet venturi vane (128) of the mill, the fine particles of 200 or less meshes are supplied to the burner through the mill outlet 130, finally adjusting the particle size. Coal having a large particle falls back to the grinding table 106 and is regrind.

On the other hand, foreign matter (Tramp Iron) and coal is not crushed, that is, the pyrite (Pyrite) is pushed to the edge of the bowl 102 by the centrifugal force of the bowl 102 and the bowl through the air passage through which the rising air rises ( To the bottom of 102). Here, the air passage is a space formed between the outer circumferential surface of the bowl 102 and the differentiator main body 134.

This foreign matter is collected by a scraper (132) attached to the bowl hub (Bowl Hub, 104) is discharged to the pyrite hopper (Pyrite Hopper, not shown) through the foreign matter outlet (Tramp Iron Opening, not shown).

Meanwhile, a bowl extension ring 120 extending upwardly at the end of the grinding table 106 in order to effectively transport the pulverized coal and drop the pulverized coal back to the grinding table 106 in the conventional bowl grinding machine. It is provided with a vane wheel blade (Vane Wheel Blade, 116) and the air control ring (Air Restriction Ring, 118) on the outer circumferential surface of the grinding table 106, the upper part of the vane wheel blade 116, the grinding body (134) It was to have a vane wheel 122 attached to it.

Figure 2a is a view showing the configuration of the air passage and the flow of rising air in the conventional bowl grinding machine, Figure 2b is a view showing the installation state of the vane wheel blade and the air control ring in the conventional bowl grinding machine.

2A and 2B, the bowl extension ring 120 provided at the end of the conventional grinding table of the grinding mill and the air adjusting ring 118 and vanes provided on the outer circumferential surface of the grinding table 106. The wheel blade 116 and the vane wheel 122 are provided. The vane wheels 122 are provided between the respective grinding rollers 108 to guide or restrict the flow of the rising air so that the pulverized coal is effectively transferred to the grinding mill outlet 130.

In particular, the vane wheel blade 116 induces the rising air to flow in the opposite direction of rotation of the grinding table 106 so that the finely divided coal particles lose momentum and fall back to the top of the grinding table 106. In addition, the air control ring 118 serves to adjust the flow rate of the rising air, the bowl extension ring 120 to prevent the coal on the grinding table 106 is pushed out.

However, the conventional bowl grinding mechanism has the following problems.

By the centrifugal force generated while the grinding table 106 is rotated, foreign matter such as pulverized coal particles 204 and iron ore, i.e., pyrite, is pushed out of the grinding table 106 and passes through the bowl extension ring 120 to pass through the air passage. Drop to 210.

However, although the pulverized coal particles 204 included in the pyrite have a smaller specific gravity than other foreign substances such as stones, the velocity of the rising air passing through the vane wheel blade 116 and the air control ring 118 is increased. Not enough will fall to the bottom of the bowl with other debris.

By the way, there also exists a problem of making the speed of the rising air which conveys pulverized coal more than a fixed speed. Typically, the proper speed of the rising air is more than 15 meters per second or less than 25 meters, but if the speed of the rising air is too high, there is a problem of rapid wear of the inside of the mill and the coal supply pipe 114.

Therefore, in the conventional bowl grinding machine, a large amount of coal is contained in the pyrite and the waste of coal cannot be solved. In addition, the pyrites are collected and landfilled in the ash processing plant. In addition to the foreign substances such as stones and iron ore, coal is additionally discharged into the pyrites. Cause.

On the other hand, the rising air passing through the vane wheel blade 116 does not flow in a constant direction, but forms a vortex, which has a problem of wearing the inside of the differentiator and the bowl extension ring 120.

That is, the vane wheel blade 116 and the vane wheel 122 and the air control ring 118 designed to effectively discharge the pyrite generate a vortex in the rising air on the one hand, causing a problem of wearing various parts of the differentiator. I was.

The present invention was devised to solve the above-mentioned problems, and the coal outflow reduction device of the bowl grinding machine can reduce the finely divided coal particles discharged to the lower part of the bowl grinding powder while effectively discharging foreign matters such as stones or iron ore contained in the coal. To provide for that purpose.

In addition, the present invention prevents abrasion of the pulverized components by preventing the rising air supplied from the bowl lower part of the bowl pulverizer after passing through the air passages and increasing the air velocity so that pulverized coal transportation is not impeded. It is an object of the present invention to provide a coal dust abatement device for a pulverizer.

In order to achieve the above object, the present invention provides a coal outflow reduction device of a bowl grinding machine for pulverizing coal and supplying pulverized coal, which is coupled to an upper side of an air control ring provided on a lower side of a bowl extension ring and an upper side of a bowl extension ring. Wherein, a vertical surface is formed in the vertical direction of the air control ring, a first inclined surface is formed in which the upper end of the vertical surface is inclined in the inner bowl direction, the upper end of the first inclined surface is the lower bowl extending ring direction End weir is formed to be inclined to form a second inclined surface coupled to the upper portion of the bowl extension ring; And a vane wheel blade formed in a flat plate shape in the radial direction at the lower outer peripheral surface of the air control ring and connected at one end thereof to an upper end of the vane wheel blade, so as to widen the area in the radial direction from the outer peripheral surface of the air control ring. The other end is not connected to the upper end of the tip plate which is formed in a wedge shape inclined with respect to the radial normal from the outer peripheral surface of the air control ring; provides a coal outflow reduction device of the bowl grinding machine comprising a.

According to the present invention, in a bowl grinding machine in which coal is pulverized into pulverized coal, the speed of the air passing through the air passage and the vortex are prevented to prevent the pulverized coal particles from falling to the bottom of the bowl, It is effective to smooth the transfer.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

3 is a perspective view showing a part of the coal outflow reduction device of the bowl grinding mill according to the present invention, Figure 4 is a cross-sectional view showing a part of the coal outflow reduction device of the bowl grinding mill according to the present invention.

3 and 4, the coal outflow reducing device of the bowl mill according to the present invention includes an upper side of the air control ring 118 and a bowl extension ring 120 provided below the outer circumferential surface of the bowl extension ring 120. Is coupled to the outer peripheral surface of the, the vertical surface 307 is formed in the vertical direction of the air control ring 118, the upper end of the vertical surface 307 is formed to be inclined in the direction of the upper surface of the inner bowl extension ring 120 The first inclined surface 305 is formed, the upper end of the first inclined surface 305 is formed to be inclined toward the lower bowl extending ring 120, the second inclined surface coupled to the upper portion of the bowl extension ring 120 ( An end weir 310 in which 303 is formed; And a radially flat plate shape at a lower outer circumferential surface of the air control ring 118 so that one end is connected to the upper end of the vane wheel blade 116 and coupled to the upper circumferential surface of the air control ring 118. Tip plate that is formed in the wedge shape inclined with respect to the radial normal from the outer circumferential surface of the air control ring 118, the other end is not connected to the upper end of the vane wheel blade 116 so as to widen the area , 320).

Coal outflow reducing device of the bowl grinding machine according to the present invention, the upper end of the air control ring 118 provided on the lower outer peripheral surface of the bowl extension ring 120 and the end weir 310 is provided on the outer peripheral surface of the bowl extension ring 120 This prevents vortices occurring in the bowl extension ring 120 and the air control ring 118 and optimizes the speed and direction of the rising air, and the outer circumferential surface of the air control ring 118 and the upper side of the vane wheel blade 116. The tip plate 320 guides the flow of rising air flowing through the vane wheel blade 116 toward the upper surface of the inner bowl extension ring 120 so that coal can be effectively suspended, thereby maximizing the outflow of coal. It is characterized by having a structure to reduce.

End weir 310 is composed of a vertical surface 307, the first inclined surface 305 and the second inclined surface 303, the vertical surface 307 is coupled to the upper side of the air control ring 118 and the second inclined surface 303 Is coupled to the outer peripheral surface of the bowl extension ring 120.

That is, the end weir 310 is coupled to the upper side of the air control ring 118 provided on the lower outer peripheral surface of the bowl extension ring 120 and the outer peripheral surface of the bowl extension ring 120, the vertical direction of the air control ring 118 The vertical surface 307 is formed, the first inclined surface 305 is formed to be inclined in the direction of the upper surface of the inner bowl extension ring 120 from the upper end of the vertical surface 307, the upper side of the first inclined surface 305 A second slope 303 is formed to be inclined in the direction of the bowl extension ring 120 at the lower side to be coupled to the upper portion of the bowl extension ring 120 from the end.

The vertical surface 307, the first inclined surface 305 and the second inclined surface 303 are each formed separately and joined by welding or the like, or the upper end of the vertical surface 307 of the inner bowl extension ring 120 The first inclined surface 305 is bent by bending in a plane direction, and the upper end of the first inclined surface 305 is bent toward the lower bowl extension ring 120 to form a second inclined surface 303. It may be formed.

By providing the vertical surface 307 and the first inclined surface 305 to suppress the vortex generated from the upper side of the air control ring 118, in particular in the direction of the upper surface of the inner bowl extension ring 120 from the vertical surface 307 Since the first inclined surface 305 is formed to be inclined, the air introduced from the vane wheel blade 116 rises vertically and rapidly collides with the differentiator body 134 and the vane wheel 122 to prevent turbulence from occurring. .

That is, the upper portion of the inner bowl extension ring 120 rides on the first inclined surface 305 from the vertical surface 307 before the air introduced between the differential surface body 134 parallel to the vertical surface 307 collides with the vane wheel 122. The first inclined plane 305 induces a change in the direction of air flow so that the flow of air in the plane direction is gently deformed to optimize the direction and velocity of air between the first inclined plane 305 and the differentiator body 134. Will be.

Here, the first inclined surface 305 is formed to be inclined 20 degrees to 25 degrees in the direction of the inner bowl extension ring 120 from the vertical surface 307 so that the flow of the vertical rising air is gently deformed.

In addition, the second inclined surface 303 is formed to be inclined in the direction of the lower bowl extension ring 120 to be coupled to the upper portion of the bowl extension ring 120, so that coal is not crushed down the second inclined surface 303 It falls to the grinding table 106 of the.

Here, the second inclined surface 303 is formed to be inclined 15 degrees to 20 degrees in the direction of the upper surface of the lower bowl extension ring 120 from the horizontal plane based on the upper end of the first inclined surface.

On the other hand, the lower end of the weir 310 is provided with a tip plate 320 so that the rising air generated in the vane wheel blade 116 is guided in the direction of the upper surface of the inner bowl extension ring 120 of the differentiator.

The tip plate 320 serves to change the speed and direction of the rising air flowing from the lower side to the upper side of the vane wheel blade 116 provided on the lower side of the air control ring 118. The vane wheel blade 116 The upper end of the and is coupled to the outer peripheral surface of the air control ring (118).

That is, the lower outer peripheral surface of the air control ring 118 is formed in a radial flat plate shape, one end is connected to the upper end of the vane wheel blade 116 is coupled, the radial direction from the outer peripheral surface of the air control ring 118 It is formed in a wedge shape so that the area becomes wider.

The flat tip plate 320 is formed to be inclined at a predetermined angle with respect to the radial normal from the outer circumferential surface of the air control ring 118, the other end is not connected to the upper end of the vane wheel blade 116, From the air control ring 118 to the differentiator body 134 has a shape that is wider, where the tip plate is the other end that is not connected to the upper end of the vane wheel blade 116 is the air control ring 118 25 degrees to 35 degrees with respect to the radial normal from the outer circumferential surface of the

Since the shape of the tip plate 320 becomes wider from the air control ring 118 to the inner circumferential surface of the differentiator body 134, the rising air between the vane wheel blades 116 is relatively larger toward the differentiator body 134. The passage space becomes narrow.

Therefore, the rising air flowing from the lower side to the upper side of the vane wheel blade 116 is faster than the portion of the air adjusting ring 118 at the portion of the grinding body 134, and naturally of the branching bowl extension ring 120 The flow of air is directed toward the upper surface.

The rising air induced in the upper direction of the vane wheel blade 116 is gently changed in the direction of the upper surface of the inner bowl extension ring 120 by the first inclined surface 305 to minimize the generation of vortex At the same time, the coal flow is effectively suspended due to the increased flow rate, which minimizes the outflow of pulverized coal.

According to the present invention having such a structure and shape, in a bowl grinding machine in which coal is pulverized into pulverized coal, the pulverized coal particles fall to the bottom of the bowl by increasing the speed of air passing through the air passage and preventing vortex. At the same time it is effective to prevent the transfer of pulverized coal at the same time.

In the above, it is described that all the components constituting the embodiment of the present invention are combined or operated in one, the present invention is not necessarily limited to these embodiments. That is, within the scope of the present invention, all of the components may be selectively combined with one or more to operate.

In addition, the terms "comprise", "comprise" or "having" described above mean that the corresponding component may be included, unless otherwise stated, and thus excludes other components. It should be construed that it may further include other components instead.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention belongs may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas falling within the scope of the present invention should be interpreted as being included in the scope of the present invention.

1 shows a schematic configuration of a conventional bowl differentiator;

FIG. 2A illustrates the configuration of air passages and the flow of rising air in a conventional bowl mill; FIG.

Figure 2b is a view showing the installation state of the vane wheel blades and the air control ring in the conventional bowl differentiator;

Figure 3 is a perspective view showing a part of the coal spill reduction device of the bowl grinding mill according to the present invention;

Figure 4 is a cross-sectional view showing a part of the coal outflow reduction device of the bowl grinding mill according to the present invention.

<Description of the symbols for the main parts of the drawings>

106: grinding table 116: vane wheel blade

118: air adjustment ring 120: bowl extension ring

134: differentiator body 303: second inclined plane

305: first inclined plane 307: vertical plane

310: End Weir 320: Tip Plate

Claims (4)

In the coal pulverization reduction apparatus of the bowl pulverizer which grinds coal and supplies pulverized coal, It is coupled to the upper side of the air control ring provided on the lower side of the bowl extending ring and the upper side of the outer circumferential surface of the bowl extension ring, the vertical surface is formed in the vertical direction of the air control ring, from the upper end of the vertical surface in the inner bowl extension ring direction An end weir formed to be inclined to form a first inclined surface, the inclined end of the first inclined surface toward an upper surface of the bowl extension ring downward, and having a second inclined surface coupled to an upper portion of the bowl extension ring; And The vane wheel blades are formed in the shape of a flat plate in the radial direction on the lower outer peripheral surface of the air control ring so that one end thereof is connected to the upper end of the vane wheel blade and is widened in the radial direction from the outer peripheral surface of the air control ring. A tip plate having another end portion not connected to an upper end portion formed in a wedge shape inclined with respect to a radial normal from an outer circumferential surface of the air adjusting ring; Bowl outflow coal coal reduction apparatus comprising a. The method of claim 1, The first slope is characterized in that the coal outflow reduction device of the bowl mill, characterized in that formed inclined 20 to 25 degrees in the direction of the inner bowl extending ring from the vertical surface. The method of claim 1, And the second inclined surface is inclined 15 degrees to 20 degrees in a direction of an upper surface of the bowl extension ring below the horizontal plane with respect to the upper end of the first inclined surface. The method of claim 1, The tip plate has the other end portion, which is not connected to the upper end of the vane wheel blade, is formed to be inclined 25 to 35 degrees with respect to the radial normal from the outer circumferential surface of the air control ring, the coal outflow reduction of the bowl grinding machine Device.

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