JP2012223675A - Vertical crushing device, dust coal manufacturing device, and coal fired boiler plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vertical crushing device that facilitate extraction of a center cone from a crushing device, saves the time and trouble for replacement, and makes replacing operation efficient.SOLUTION: The vertical crushing device which includes a crushing table 2 rotating while provided with a center cone 75 on an upper surface of a center part and a crushing roller 3 mounted on the crushing table 2, and crushes coal 60 thrown in from above the center cone 75 with the crushing table 2 and crushing roller 3 is characterized in that the center cone 75 is divided into a plurality of stages in a height direction and the center cone 75 is constituted by stacking and connecting the division cone members 70, 71.

Description

  The present invention relates to a vertical pulverizer capable of pulverizing a solid raw material by the cooperation of a rotating pulverizer such as a pulverizing roller and a pulverizing table, and adjusting the pulverized particles to a predetermined particle size distribution in a classifying unit, In particular, the present invention relates to a vertical crusher suitable for use as a pulverized coal production apparatus for a coal-fired boiler plant.

  Hereinafter, assuming the case of pulverizing coal, for example, the pulverized raw material will be described as “coal”, and the pulverized raw material supply pipe for supplying the pulverized raw material will be described as “coal supply pipe”. However, the pulverized raw material is a solid raw material in general, and the kind of raw material is not limited.

  In a coal-fired boiler plant for thermal power generation in which pulverized coal is burned as a fuel, a vertical pulverizer is conventionally used as a pulverized coal production apparatus.

FIG. 10 is a schematic configuration diagram of a conventional vertical crusher.
This vertical crushing apparatus includes a driving unit A that rotates the crushing table 2, a crushing unit B that crushes the coal 60 that is a raw material of pulverized coal by the biting of the crushing table 2 and the crushing roller 3, and the crushing unit B A classifying unit C for classifying a particle group generated by being installed at the upper part of the slab into an arbitrary particle size, and a plurality of pulverized coals connected to a boiler device (not shown) with pulverized coal classified in the classifying unit C It is mainly composed of a distribution unit D that distributes to the supply pipe 31.

Next, the operation of this vertical crusher will be described with reference to FIG.
The massive coal 60 supplied from the coal supply pipe 1 falls to the center of the crushing table 2 as indicated by the arrows. The crushing table 2 is rotationally driven by a drive motor 51 via a speed reducer 50. The coal 60 dropped on the pulverizing section B collides with the center cone 72 installed on the upper surface of the central portion of the pulverizing table 2 to prevent wear of the pulverizing table 2 and improve the dispersibility of the coal. 2 is moved to a circumferential groove 4 formed in the outer peripheral portion while drawing a spiral trajectory, and is crushed by being caught between the grinding table 2 and the tire-like grinding roller 3.

  In this example, the grinding roller 3 is used as the grinding member, but a grinding ball may be used. These crushing members (crushing rollers and crushing balls) are placed on the crushing table 2 and roll on the crushing table 2 as the crushing table 2 rotates, and the crushing table 2 and crushing members (crushing rollers and crushing balls). ) Mechanically pulverize coal 60 and the like.

  The pulverized powder 59 is blown upward by high-temperature primary air 61 (also serving as air for conveyance / drying) introduced from a throat 42 provided around the pulverization table 2. This example is called a rotary swirl flow throat in which the throat 42 rotates together with the crushing table 2, but there may be a fixed swirl flow throat in which the throat 42 is fixed to the outer peripheral housing 46 of the grinder.

  Of the powder 59 blown up, a heavy particle having a large particle diameter falls by gravity while being conveyed to the classification unit C, and is returned to the pulverization unit B (primary classification). The particle group 62 that has reached the classification part C is given a turning force to the particles by the fixed fins 12 and the rotating fins 21, and is separated into fine particles 64 having a predetermined particle size or less and coarse particles 63 having a predetermined particle size (2). Next classification).

  The coarse particles 63 fall onto the pulverizing table 2 of the pulverizing section B through the recovery hopper 11 provided below the fixed fins 12, and are pulverized again. On the other hand, the fine particles 64 that have passed through the classification section C are distributed to the plurality of pulverized coal feed pipes 31 by the distributor 30 and are conveyed to the boiler apparatus (not shown) as fuel.

  As shown in the figure, the lower end opening 10 of the hopper 11 is disposed between the lower end opening of the coal feeding pipe 1 and the grinding table on the center axis of the center cone 72 and opens toward the center cone 72. Yes.

  In this example, an example of a rotary classifier using a rotary fin 12 for secondary classification has been shown. However, in the case of a fixed classifier that applies a turning force to particles by a fixed swirling blade and separates into fine particles and coarse particles. is there.

  The conventional center cone 72 has a substantially conical shape with a sharp upper end as described in Patent Documents 1 and 2, for example (see FIG. 10).

JP 2001-113192 A Japanese Patent Laid-Open No. 7-275729

  As described above, the center cone 72 installed at the center of the crushing table 2 falls and collides with solids such as the coal 60 and the coarse particles 63 from directly above, so the wear is intense and the replacement frequency of parts is high. The conventional center cone 72 is integrally formed as a whole, and is large and heavy.

  Therefore, conventionally, when the center cone 72 is replaced, various members such as the pressure frame 5, the roller bracket 6, and the roller pivot 7 existing around the center cone 72 are removed, and then the grinding roller 3 is taken out. The whole was exchanged. After the replacement, it is necessary to attach the removed grinding roller 3, pressure frame 5, roller bracket 6, roller pivot 7 and the like to their original state. For this reason, the time and labor required for the replacement work of the center cone 72 are great, and the work efficiency is poor.

Next, the problem regarding the dispersibility of the material to be pulverized (coal 60, coarse particles 63) charged on the pulverization table 2 on the pulverization table 2 and the pulverizability of the material to be pulverized will be described.
FIG. 11 is a diagram for explaining the flow of the material to be crushed around the center cone 72 in the conventional vertical crusher, and FIG. 11 (a) is an enlarged plan view of the vicinity of the center cone 72, FIG. b) is an enlarged side view of the vicinity of the center cone 72. FIG.

  As shown in FIG. 10, the coal 60 supplied from the coal supply pipe 1 and the coarse particles 63 collected from the hopper 11 are put into the pulverizing unit B, collide with the center cone 72 and dispersed on the pulverizing table 2. . At this time, in order to uniformly supply the object to be crushed onto the crushing table 2 (a plurality of crushing rollers 3), ideally, as shown in FIG. Forming a high-concentration drop region 65 of the object to be crushed.

  However, it is very difficult to consistently align the center of the high-concentration falling region of the material to be crushed falling from the coal supply pipe 1 or the hopper 11 with the central axis of the center cone 72. In practice, for example, as shown by the oblique lines, the high concentration falling region 66 is often shifted from the center axis of the center cone 72, and the distribution of the object to be crushed on the horizontal plane is biased with respect to the center axis of the center cone 72. There is a tendency.

  Since the conventional center cone 72 has a conical shape, the object to be crushed is dispersed outward in the radial direction without changing the aforementioned uneven distribution. Therefore, on the center cone 72, as shown in FIG. 11 (b), a flow 67a with a large amount of material to be crushed and a flow 67b with a small amount of material to be crushed are generated. The object to be crushed was not constantly and evenly supplied to the pulverizing roller 3.

As described above, if the pulverized material is not constantly and evenly supplied to the plurality of pulverizing rollers 3, the following problems occur. That is,
(1) The object to be pulverized concentrates on a specific pulverizing roller 3 to reduce the pulverization efficiency and increase the pulverization power.

(2) The wear of the grinding roller 3 is biased.

(3) Since the layer of the object to be crushed on the pulverization table 2 is partially thick, a deviation occurs in the flow of the primary air 61 blown from the throat 42, and the primary classification efficiency is lowered.

  The object of the present invention is to eliminate such drawbacks of the prior art, to easily take out the center cone from the crushing apparatus, to reduce the time and labor required for replacement, and to improve the efficiency of replacement work. Another object of the present invention is to provide a vertical crushing apparatus, a pulverized coal production apparatus, and a coal-fired boiler plant equipped with the same, in which a material to be crushed is constantly and evenly supplied to a crushing member such as a crushing roller.

In order to achieve the above object, the present invention provides:
A crushing table that rotates with a center cone provided on the upper surface of the center;
A plurality of crushing members such as crushing rollers mounted on the crushing table and rolling by rotation of the crushing table,
The present invention is intended for a vertical crushing apparatus that crushes an object to be crushed, such as coal, supplied from above the center cone at a biting portion of the crushing table and a crushing member.

  In the first means of the present invention, the center cone is divided into a plurality of stages in the height direction thereof, and the center cone is configured by stacking and connecting the divided cone members. It is characterized by.

According to a second means of the present invention, in the first means,
The center cone is detachably fixed to the crushing table.

According to a third means of the present invention, in the first means,
The center cone is composed of a lower divided cone member and an upper divided cone member disposed on the upper side of the lower divided cone member,
When the height of the upper split cone member is L1, the height of the lower split cone member is L2, and the total height (L1 + L2) of the center cone is L3, the upper split with respect to the total height L3 of the center cone The ratio (L1 / L3) of the height L1 of the cone member is regulated within the following range.

0.2 ≦ L1 / L3 ≦ 0.6
A fourth means of the present invention is the first or third means,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member constituting the upper side of the center cone,
The inclination angle formed between the bottom surface of the lower divided cone member and the inclined circumferential surface is different from the inclination angle formed between the bottom surface of the upper divided cone member and the inclined circumferential surface.

According to a fifth means of the present invention, in the fourth means,
The tilt angle of the lower split cone member is larger than the tilt angle of the upper split cone member.

A sixth means of the present invention is the first or third means,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member constituting the upper side of the center cone,
The inclination angle formed between the bottom surface of the lower divided cone member and the inclined circumferential surface is substantially equal to the inclination angle formed between the bottom surface of the upper divided cone member and the inclined circumferential surface.

A seventh means of the present invention is the fourth to sixth means,
The angle of inclination of each of the divided cone members is restricted to a range of 20 ° to 50 °.

The eighth means of the present invention is the fourth or fifth means,
The difference between the tilt angle of the lower split cone member and the tilt angle of the upper split cone member is restricted to a range of more than 0 ° and not more than 10 °.

A ninth means of the present invention is the first to eighth means,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member disposed on the upper side of the lower divided cone member,
An intermediate horizontal portion concentric with the central axis of the center cone is provided at the joint between the lower divided cone member and the upper divided cone member.

The tenth means of the present invention is the ninth means,
The intermediate horizontal portion is constituted by an upper portion of the lower divided cone member such as an upper disk described later and a lower portion of the upper divided cone member such as a lower disk described later, and the lower divided cone member. And an upper split cone member to be connected to or separated from each other.

The eleventh means of the present invention is the ninth or tenth means,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The ratio (d3 / d5) of the diameter d3 of the intermediate horizontal portion to the inner diameter d5 of the pulverized raw material supply pipe when the diameter of the intermediate horizontal portion is d3 and the inner diameter of the pulverized raw material supply pipe is d5 is as follows. It is characterized by being regulated by

0.5 ≦ d3 / d5 ≦ 1.5
A twelfth means of the present invention is the first to eleventh means,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The circumferential side plate of the upper divided cone member with respect to the inner diameter d5 of the pulverized raw material supply pipe when the lower end diameter of the circumferential side plate constituting the upper divided corn member is d2 and the inner diameter of the pulverized raw material supply pipe is d5. The ratio (d2 / d5) of the lower end diameter d2 is regulated within the following range.

0.4 ≦ d2 / d5 ≦ 1.0
A thirteenth means of the present invention is the first to twelfth means,
An upper horizontal portion concentric with the center axis of the center cone is provided on the top surface of the uppermost divided cone member disposed on the uppermost side of the center cone.

The fourteenth means of the present invention is the thirteenth means,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The diameter d1 of the upper horizontal portion of the upper divided cone member with respect to the inner diameter d5 of the pulverized raw material supply pipe when the diameter of the upper horizontal portion of the uppermost divided cone member is d1 and the inner diameter of the crushed raw material supply pipe is d5. The ratio (d1 / d5) is regulated within the following range.

0.05 ≦ d1 / d5 ≦ 0.2
The fifteenth means of the present invention includes
A vertical crusher;
A coal supply pipe for charging coal to be crushed from the top of the vertical crusher;
In the pulverized coal production apparatus provided with the pulverized coal feeding pipe for feeding the pulverized coal generated by pulverization with the vertical pulverizer to the pulverized coal supply destination,
The vertical crusher is the vertical crusher of the first to fifteenth means.

The sixteenth means of the present invention is the fifteenth means,
A throat is provided around the crushing table of the vertical crusher,
Classification means having a recovery hopper is provided above the grinding table,
Blowing up the coal particles pulverized at the biting portion of the pulverization table and the rolling pulverization member to the upper classification means side with the conveying gas introduced from the throat,
The particle group is divided into pulverized coal and coarse particles by the classification means, and the coarse particles are dropped from above the center cone through the recovery hopper and pulverized again. .

The seventeenth means of the present invention is
Pulverized coal production equipment,
In a coal-fired boiler plant equipped with a coal-fired boiler device that introduces and burns pulverized coal produced by the pulverized coal production device,
The pulverized coal production apparatus is the pulverized coal production apparatus of the fifteenth or sixteenth means.

  As described above, the present invention can divide the center cone attached to the crushing table into two or more upper and lower stages, so that it is possible to replace only the divided cone member that is severely worn and damaged by the drop impact of the object to be crushed. is there. Since this divided cone member is light in weight and small in size, it can be easily taken out from the crushing apparatus, the time and labor required for replacement can be reduced, and the efficiency of replacement work can be improved.

  Further, since the individual divided cone members constituting the center cone are small in size and light in weight, it is easy to manufacture and repair the divided cone members.

  Furthermore, since the object to be pulverized is constantly and evenly supplied to a plurality of pulverizing members, the object to be pulverized concentrates on a specific pulverizing member, the pulverization efficiency decreases, the pulverization power increases, The disadvantages such as uneven wear of the members and deviation in the flow of the conveying gas blown up from the throat are also eliminated.

1 is a schematic configuration diagram of a vertical crusher according to a first embodiment of the present invention. It is an expanded sectional view of the center cone used for the vertical mill. It is an enlarged plan view of the center cone. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the mode of the flow of the to-be-ground material around the center cone which concerns on 1st Embodiment of this invention, The figure (a) is an enlarged plan view of the center cone vicinity, The figure (b) is a center cone. It is an enlarged side view of the vicinity. It is a figure which shows the mode of the repulsion of the to-be-ground object in the center cone used for the conventional vertical mill. It is a figure which shows the mode of the repulsion of the to-be-ground object in the center cone which concerns on 1st Embodiment of this invention. It is an expanded sectional view of the center cone which concerns on 2nd Embodiment of this invention. It is an enlarged side view of the center cone which concerns on 3rd Embodiment of this invention. It is a distribution diagram of a coal fired boiler plant provided with a vertical crusher concerning an embodiment of the present invention. It is a schematic structure figure showing an example of the conventional vertical crusher. It is a figure for demonstrating the mode of the flow of the to-be-ground material in the center cone periphery in the conventional vertical crushing apparatus, The figure (a) is an enlarged plan view of the center cone vicinity, The figure (b) is the center cone vicinity. It is an enlarged side view.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a vertical crusher according to a first embodiment of the present invention.
In this embodiment, the center cone 75 is different from the conventional vertical crusher shown in FIG. FIG. 2 is an enlarged sectional view for explaining the configuration of the center cone 75, and FIG. 3 is an enlarged plan view of the center cone 75.

  As shown in FIGS. 1 to 3, the center cone 75 includes a lower divided cone member 70 having a substantially frustoconical shape, and an upper portion having a substantially frustoconical shape that is installed at the upper center of the lower divided cone member 70. It is comprised from the division | segmentation cone member 71. FIG. The upper divided cone member 71 has substantially the same truncated cone shape as the lower divided cone member 70, but the overall size is smaller than that of the lower divided cone member 70.

  The lower divided cone member 70 includes a lower disk 76, a circumferential side plate 77 that is installed on the lower disk 76 and is inclined downwardly toward the bottom, and an upper side of the circumferential side plate 77. It is comprised from the upper side disk 78 installed in this, and it is hollow and the whole shape is a substantially truncated cone shape. The diameter d7 of the lower disc 76 is slightly larger than the lower end diameter d4 of the circumferential plate 77, and a center cone attaching portion 68 is formed on the outer periphery of the lower disc 76 due to the difference in diameter. Yes.

  The upper divided cone member 71 includes a lower disk 79, a circumferential side plate 80 which is installed on the lower disk 79 and is inclined downwardly toward the lower side, and the circumferential side plate 80. It is comprised from the upper side disc 81 installed on the top, and it is hollow and the whole shape is a substantially truncated cone shape.

  The upper disk 78 of the lower divided cone member 70 and the lower disk 79 of the upper divided cone member 71 have the same diameter, and the diameter d3 of the upper disk 78 and the lower disk 79 is the lower end diameter d2 of the circumferential plate 80. The intermediate horizontal portion 73 is formed on the outer peripheral portions of the upper disc 78 and the lower disc 79 due to the difference in diameter.

  Further, when assembling the center cone 75, the lower disk 79 is placed on the upper disk 78, and the flange part (intermediate horizontal part 73) outside the circumferential disk 80 of the upper disk 78 and the lower disk 79. ), The lower divided cone member 70 and the upper divided cone member 71 are connected. Further, by loosening the bolt 67, the lower divided cone member 70 and the upper divided cone member 71 are separated. Accordingly, the intermediate horizontal portion 73 formed at the joint between the lower divided cone member 70 and the upper divided cone member 71 also serves as a connecting / separating portion for the lower divided cone member 70 and the upper divided cone member 71. .

  In this way, the lower divided cone member 70 and the upper divided cone member 71 can be separated, and are individually small in size and light in weight. Therefore, a maintenance door (on the side surface of the housing 46 on the outer periphery of the apparatus) ( The upper divided cone member 7 and / or the lower divided cone member 70 can be directly taken in and out from the opening portion (not shown).

  Therefore, when replacing the split cone member, there is no need for a large-scale work such as removing other members around the center cone and installing it again after replacement as before, and the replacement work is simplified and the efficiency can be improved. .

  As shown in FIG. 2, a center cone attaching portion 68 is provided on the lower outer peripheral portion of the center cone 75. By fixing this portion to the grinding table 2 with a plurality of bolts 82, the center cone 75 itself is also ground. It is attached to the table 2 in a replaceable manner.

  As described above, the intermediate horizontal portion 73 is constituted by the upper disc 78 and the lower disc 79, and this intermediate horizontal portion 73 (shaded portion) is centered on the central axis 84 of the center cone 75 as shown in FIG. It is a concentric circle.

  In the case of this embodiment, the center cone 75 is divided into two upper and lower stages, and the upper divided cone member 71 is the uppermost divided cone member. A concentric upper horizontal portion 74 (shaded portion) centering on the central axis 84 of the center cone 75 is formed. The functions of the intermediate horizontal portion 73 and the upper horizontal portion 74 will be described later.

  When the upper horizontal portion 74 is covered with a wear-resistant cover made of, for example, a substantially hemispherical rounded shape or a cast having a sharp upper shape such as a cone, the wear of the center cone 75 is the most. The remarkable wear resistance of the upper part of the center cone can be locally increased. It is also possible to construct the substantially truncated cone upper divided cone member 71 itself from a material having excellent wear resistance.

  As shown in FIG. 2, the upper divided cone member 71 has a height L1, the lower divided cone member 70 has a height L2, and the total height of the center cone 75 is L3. By not reaching the side split cone member 70, a member that is frequently replaced can be limited (specified) to the upper split cone member 71, and the convenience of the parts replacement can be increased. The entire wear state of the center cone 75 due to the drop impact was observed.

  As a result, when the height L1 of the upper divided cone member 71 is expressed in a dimensionless manner by the total height L3, that is, the ratio of the height L1 of the upper divided cone member 71 to the total height L3 of the center cone 75 ( It was found that (L1 / L3) is preferably larger than 0.2. In view of replacement by wear, the upper divided cone member 71 is preferably as small as possible, and it has been found that the ratio (L1 / L3) should be smaller than 0.6. Therefore, it is desirable to regulate the ratio (L1 / L3) of the height L1 of the upper divided cone member 71 to the overall height L3 of the center cone 75 within the following range.

0.2 ≦ L1 / L3 ≦ 0.6
As shown in FIG. 2, the angle formed by the lower disk 76 (bottom surface) of the lower divided cone member 70 and the circumferential side plate 77, that is, the inclination angle of the inclined circumferential surface of the lower divided cone member 70 is θ2, An angle formed by the lower circular plate 79 (bottom surface) of the cone member 71 and the circumferential side plate 80, that is, an inclination angle of the inclined circumferential surface of the upper divided cone member 71 is defined as θ1. Since the particles have a property of accumulating at a certain angle (repose angle), if the inclination angles θ1 and θ2 are inappropriate, the pulverized particles are not dispersed well, so that the pulverization roller 3 pulverizes evenly. Not.

  In order to disperse the particles uniformly, it is desirable that the inclination angles θ1 and θ2 be equal to or greater than the repose angle of the object to be crushed. A typical powder has an angle of repose of approximately 15 ° to 40 °. Therefore, it is desirable that the inclination angles θ1 and θ2 are in the following ranges.

20 ° ≦ θ1, θ2 ≦ 50 °
In this embodiment, θ1 = θ2 = 40 °, but θ1 and θ2 can be arbitrarily set within the above-described range.

The function of the concentric horizontal portion 73 provided in the divided portion of the lower divided cone member 70 and the upper divided cone member 71 will be described with reference to FIGS. 4 and 11.
As shown in FIG. 11, in the conventional conical center cone 72, the actual high-concentration falling region 66 of the object to be crushed (coal 60 and coarse particles 63) deviates from the central axis of the center cone 72 as shown by the oblique lines. In many cases, the distribution of the object to be crushed on the horizontal plane is uneven. Therefore, as shown in FIG. 11B, a flow 67a with a large amount of crushed material, a flow 67b with a small amount of pulverized material, and the like are generated on the center cone 72. The object to be crushed was not constantly and evenly supplied to the crushing roller 3.

  4A and 4B are diagrams for explaining the flow of particles around the center cone 75 according to the present embodiment. FIG. 4A is an enlarged plan view near the center cone 75, and FIG. 4B is the center cone 75. It is an enlarged side view of the vicinity.

  As shown in FIG. 4A, the pulverized material (coal 60 and coarse particles 63) falling from the actual high concentration region 66 falls on the upper divided cone member 71 in a state of being biased from the center of the center cone 75. . As a result, as shown in FIG. 4 (b), a flow 67a with a large amount of material to be crushed and a flow 67b with a small amount of material to be crushed are generated, but a concentric intermediate horizontal portion provided in the center cone dividing portion (intermediate portion). The particles once accumulate in 73. Reference numeral 83 a in the figure indicates particles accumulated on the intermediate horizontal portion 73. Thus, the intermediate horizontal portion 73 has a particle retention function such as a weir or a buffer tank, and the fallen object to be crushed temporarily stays in the intermediate horizontal portion 73.

  Further, since the center cone 75 rotates together with the pulverizing table 2, the particles 83a staying in the intermediate horizontal portion 73 are sequentially placed on the respective pulverizing roller 3 (pulverizing table 2) side by centrifugal force and vibration during rotation. Distributed to. Therefore, due to the retention of the particles in the intermediate horizontal portion 73 and the dispersion of the retained particles, the circumferential deviation of the particles dispersed on the pulverization table 2 is reduced, and the pulverization object that has been biased by the respective pulverization rollers 3 in the past is reduced. Things are evenly distributed, so that the particles are evenly crushed by each pulverizing roller 3.

  Here, judging from the wear situation of the center cone 75, considering that the actual diameter d6 of the high-concentration drop region 66 is about half of the inner diameter d5 of the coal feeding pipe 1, the high-concentration drop region 66 is the intermediate horizontal. Since it is not desirable to be outside the portion 73, it is preferable that the diameter d3 of the intermediate horizontal portion 73 be 0.5 times or more the inner diameter d5 of the coal feeding pipe 1.

  In consideration of convenience when replacing the upper divided cone member 71, the diameter d3 of the intermediate horizontal portion 73 is preferably 1.5 times or less the inner diameter d5 of the coal feeding pipe 1. Therefore, if the diameter d3 of the intermediate horizontal portion 73 is expressed in a dimensionless manner by the inner diameter d5 of the coal feeding pipe 1, the ratio of the diameter d3 of the intermediate horizontal portion 73 to the inner diameter d5 of the coal feeding pipe 1 (d3 / d5) is The following range is desirable.

0.5 ≦ d3 / d5 ≦ 1.5
Further, with respect to the bottom surface diameter (lower end diameter of the circumferential side plate 80) d2 of the upper divided cone member 71 having a substantially frustoconical shape, the high concentration region 66 in the coal feeding pipe 1 is a cone inclined portion ( Since the particles are more evenly dispersed when colliding with the circumferential side plate 80), the larger one is preferable, but it is necessary to consider the convenience at the time of exchanging the upper divided cone member 71. Considering a preferable range of the diameter d3 of the intermediate horizontal portion 73, a preferable range of the bottom surface diameter d2 of the upper divided cone member 71 is expressed in a dimensionless manner by the inner diameter d5 of the coal supply pipe 1, that is, a coal supply pipe. The ratio (d2 / d5) of the bottom surface diameter d2 of the upper divided cone member 71 to the inner diameter d5 of 1 is in the following range.

0.4 ≦ d2 / d5 ≦ 1.0
The upper horizontal portion 74 provided at the top of the upper divided cone member 71 also has the same function as the intermediate horizontal portion 73, and the retention of the object to be crushed on the upper horizontal portion 74 and the crushing table 2 ( The dispersion of the staying particles accompanying the rotation of the center cone 75) eliminates the deviation, so that the objects to be crushed which are biased by the respective pulverizing rollers 3 are evenly dispersed. Reference numeral 83 b in the figure is particles accumulated on the upper horizontal portion 74.

  By combining the intermediate horizontal portion 73 and the upper horizontal portion 74, the central axis of the high concentration drop region 66 from the coal feeding pipe 1 is displaced from the central axis of the center cone 75 so that it cannot be covered by the intermediate horizontal portion 73. In addition, since the deviation is smoothed by the upper horizontal portion 74 of the upper divided cone member 71, there is an effect that the object to be crushed can be evenly supplied to the respective pulverizing rollers 3.

  Considering the convenience at the time of replacement and the function of the upper horizontal portion 74, a preferable range of the diameter d1 of the upper horizontal portion 74 of the upper divided cone member 71 is expressed in a dimensionless manner by the inner diameter d5 of the coal supply pipe 1. That is, the ratio (d1 / d5) of the diameter d1 of the upper horizontal portion 74 of the upper divided cone member 71 to the inner diameter d5 of the coal feeding pipe 1 is desirably in the following range.

0.05 ≦ d1 / d5 ≦ 0.2
Further, in the present invention, the inclined peripheral surfaces of the lower divided cone member 70 and the upper divided cone member 71 and the two horizontal portions 73 and 74 are provided as the repelling surfaces that are repelled by colliding with the falling crushed object.
FIG. 5 is a diagram showing a state of repulsion of the object 85 to be crushed by the conventional center cone 72. As described above, in the case of the conventional center cone 72, the uneven distribution on the horizontal plane of the pulverized object 85 that is difficult to avoid is dispersed to the outside in the radial direction as it is. The object to be crushed is not supplied evenly to the plurality of crushing rollers 3 provided.

  On the other hand, FIG. 6 is a diagram showing a state of repulsion of the object 85 to be crushed by the center cone 75 according to the present embodiment. As shown in the figure, from the upper side to the lower side of the center cone 75, the upper horizontal portion 74, the inclined circumferential surface of the upper divided cone member 71, the intermediate horizontal portion 73, and the inclined circumferential surface of the lower divided cone member 70 are It is provided in stages, and the horizontal surface and the inclined peripheral surface are alternated as the particle repulsion surface.

  As described above, since the surface to be crushed 85 collides and rebounds, and the form of the rebound surface is different (horizontal surface and inclined circumferential surface), the material to be crushed 85 rebounds in various directions as shown in FIG. And disperse. Therefore, the deviation of the distribution on the horizontal plane of the object to be crushed, (deviation in the radial direction) can be reduced, and the object to be crushed 85 is conventionally reduced by reducing the deviation in the circumferential direction by the function of the horizontal portions 73 and 74. Since it is supplied evenly to the plurality of crushing rollers 3 than when the center cone is used, the crushing efficiency can be improved.

FIG. 7 is an enlarged cross-sectional view of the center cone 75 according to the second embodiment of the present invention.
2 is different from the first embodiment shown in FIG. 2 in that the lower divided cone member 70 has a lower circular plate 76 (bottom surface) and an inclination angle θ2 formed between the circumferential side plate 77 and the upper divided cone member 71. The lower circular plate 79 (bottom surface) and the circumferential side plate 80 have different inclination angles θ1 (θ2 ≠ θ1).

  In the embodiment shown in FIG. 7, the inclination angle θ1 of the upper divided cone member 71 is smaller than the inclination angle θ2 of the lower divided cone member 70 (θ2> θ1), but conversely θ1> θ2. Is also possible.

  Thus, when the inclination angle θ1 and the inclination angle θ2 are different, the repulsion angles of the objects to be crushed that collide with the inclined surfaces of the lower divided cone member 70 and the upper divided cone member 71 are different between the inclined surfaces. Therefore, the radial distribution range (scattering range) of the particle groups repelling each inclined surface is substantially expanded, and the particles are dispersed over a wide range. That is, the radial deviation of the particle group dispersed on the pulverizing table 2 can be reduced, and therefore the dispersibility of the pulverized material can be further improved.

  Here, if the angle difference between the angles θ1 and θ2 is large, the particles tend to concentrate at a plurality of specific locations in the radial direction due to the difference in the repulsion angles of the particles. Therefore, if the angle difference (θ2−θ1 or θ1−θ2) between the angles θ1 and θ2 is within the following range, the object to be crushed can be evenly dispersed on each pulverizing roller 3.

0 ° <θ2-θ1 ≦ 10 ° or 0 ° <θ1-θ2 ≦ 10 °
Also in this embodiment, the angles θ1 and θ2 of the upper divided cone member 71 and the lower divided cone member 70, the height L1 of the upper divided cone member 71, the height L2 of the lower divided cone member 70, and the intermediate horizontal portion Preferred ranges such as the diameter d3 of 73, the bottom surface diameter d2 of the upper divided cone member 71, and the diameter d1 of the upper horizontal portion 74 are the same as the ranges described in the first embodiment.

FIG. 8 is an enlarged cross-sectional view of the center cone 75 according to the third embodiment of the present invention.
In this embodiment, the main point of difference from the first embodiment shown in FIG. 2 is that the center cone 75 has a three-stage configuration of a lower divided cone member 86, an intermediate cone member 87, and an upper divided cone member 88. It is.
A lower intermediate horizontal portion 89 is provided between the upper divided cone member 86 and the intermediate cone member 87, an upper intermediate horizontal portion 90 is provided between the intermediate cone member 87 and the upper divided cone member 88, and an upper divided cone. Upper horizontal portions 91 are respectively formed on the top surfaces of the members 88. The lower intermediate horizontal portion 89, the upper intermediate horizontal portion 90 and the upper horizontal portion 91 are formed concentrically around the central axis 84 of the center cone 75.

  In the present embodiment, the inclination angle θ of the inclined peripheral surfaces of the lower divided cone member 86, the intermediate cone member 87, and the upper divided cone member 88 is θ3> θ2 = θ1 as shown in the figure. In addition, the desirable selection range of each inclination angle θ is 20 ° or more and 50 ° or less as in the first embodiment.

  In the present embodiment, the inclination angle θ of the inclined peripheral surfaces of the lower divided cone member 86, the intermediate cone member 87, and the upper divided cone member 88 is θ3> θ2 = θ1, but θ3> θ2> θ1 It is also possible to concentrate the wear range due to the object on the upper divided cone member 88 that is most convenient to replace the member.

  In the present embodiment, as shown in FIG. 8, the upper divided cone member 88 has a height L11, the intermediate cone member 87 has a height L12, the lower divided cone member 86 has a height L13, and the center cone 75 has a total height. When the height is L14, the ratio [(L11 + L12) / L14] of the height L11 of the replaceable upper divided cone member 88 and the height L12 of the intermediate cone member 87 to the total height L14 of the center cone 75 is set. It is desirable to regulate to the following range.

0.2 ≦ [(L11 + L12) / L14] ≦ 0.6
FIG. 9 is a system diagram of a coal fired boiler plant equipped with a vertical crusher according to the embodiment.
The massive coal 60 to be crushed is put into the coal bunker 102 by the carry-in conveyor 101, and then the coal 60 is weighed by the meter 103 and fed into the vertical crusher 104 through the coal supply pipe 1. Also, from the lower part of the vertical pulverizer 104, high-temperature primary air 61 that serves as both particle transport and drying is supplied, and the coal 60 is pulverized and classified in the vertical pulverizer 104 as described above. The pulverized coal having a particle size equal to or smaller than the above is supplied to the burners 106 of the coal-fired boiler unit 105 and burned in the furnace.

  The combustion exhaust gas generated by this combustion is purified through the denitration device 107, the air preheater 108, the electrostatic precipitator 109, and the like, and discharged from a chimney (not shown) to the atmosphere.

  In the above-described embodiment, the case of pulverizing coal alone has been described. However, the present invention is also applicable to a vertical pulverizer that pulverizes a mixture with biomass such as wood pellets mainly composed of coal.

  DESCRIPTION OF SYMBOLS 1 ... Coal feeding pipe, 2 ... Grinding table, 3 ... Grinding roller, 4 ... Circumferential groove, 10 ... Lower end opening of hopper, 11 ... Hopper, 12 ... Fixed fin, 21 ... Rotary fin, 31 ... Pulverized coal feed pipe, 42 ... Throat, 46 ... Housing, 59 ... Powder, 60 ... Coal, 61 ... Primary Air, 62 ... Particle group, 63 ... Coarse particles, 64 ... Fine particles, 65 ... High concentration fall region of ideal object to be crushed, 66 ... High concentration of actual object to be crushed Falling area, 67a ... flow with much object to be crushed, 67b ... flow with little object to be crushed, 68 ... center cone attaching part, 70 ... lower divided cone member, 71 ... upper divided Cone member 73 ... Intermediate horizontal part 74 ... Upper horizontal part 75 ... Center cone 76 ... Side discs, 77 ... circumferential side plates, 78 ... upper discs, 79 ... lower discs, 80 ... circular side plates, 81 ... upper discs, 82 ... bolts 83a ... Particles collected in the middle horizontal part, 83b ... Particles collected in the upper horizontal part, 84 ... Center axis of the center cone, 85 ... Object to be crushed, 104 ... Vertical grinding Equipment: 105 ... Coal-fired boiler equipment, 106 ... Burner, A ... Drive part, B ... Grinding part, C ... Classification part, D ... Distribution part, L1 ... Upper side The height of the split cone member, L2 ... the height of the lower split cone member, L3 ... the height of the center cone, L11 ... the height of the upper split cone member, L12 ... the intermediate split cone member , L13: height of the lower divided cone member, L14: height of the center cone, θ1: upper portion Inclination angle of split cone member, θ2: Inclination angle of lower divided cone member, d1: Diameter of upper horizontal portion, d2: Lower end diameter of circumferential side plate, d3: Diameter of intermediate horizontal portion , D4: lower end diameter of the circumferential side plate, d5: inner diameter of the coal feeding pipe.

Claims (17)

A crushing table that rotates with a center cone provided on the upper surface of the center;
A plurality of crushing members mounted on the crushing table and rolling by rotation of the crushing table are provided.
In the vertical pulverizer for pulverizing the object to be crushed from above the center cone at the biting portion of the pulverization table and the pulverization member,
The vertical pulverizer characterized in that the center cone is divided into a plurality of stages in the height direction of the center cone, and the center cone is configured by stacking and connecting the divided cone members. The vertical crushing apparatus according to claim 1,
A vertical crusher characterized in that the center cone is detachably fixed to the crushing table. The vertical crushing apparatus according to claim 1,
The center cone is composed of a lower divided cone member and an upper divided cone member disposed on the upper side of the lower divided cone member,
When the height of the upper split cone member is L1, the height of the lower split cone member is L2, and the total height (L1 + L2) of the center cone is L3, the upper split with respect to the total height L3 of the center cone A vertical crusher characterized in that the ratio (L1 / L3) of the height L1 of the cone member is regulated within the following range.
0.2 ≦ L1 / L3 ≦ 0.6 The vertical crusher according to claim 1 or 3,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member constituting the upper side of the center cone,
A vertical crusher characterized in that an inclination angle formed between the bottom surface of the lower divided cone member and the inclined circumferential surface is different from an inclination angle formed between the bottom surface of the upper divided cone member and the inclined circumferential surface. The vertical crusher according to claim 4,
The vertical crusher characterized in that an inclination angle of the lower divided cone member is larger than an inclined angle of the upper divided cone member. The vertical crusher according to claim 1 or 3,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member constituting the upper side of the center cone,
A vertical crusher characterized in that an inclination angle formed between the bottom surface of the lower divided cone member and the inclined peripheral surface is substantially equal to an inclination angle formed between the bottom surface of the upper divided cone member and the inclined peripheral surface. The vertical crushing apparatus according to any one of claims 4 to 6,
A vertical crusher characterized in that an inclination angle of each divided cone member is regulated within a range of 20 ° to 50 °. The vertical crushing apparatus according to claim 4 or 5,
A vertical crusher characterized in that a difference between an inclination angle of the lower divided cone member and an inclined angle of the upper divided cone member is regulated within a range of more than 0 ° and not more than 10 °. The vertical crusher according to any one of claims 1 to 8,
The center cone has at least a lower divided cone member constituting the lower side of the center cone, and an upper divided cone member disposed on the upper side of the lower divided cone member,
A vertical crusher characterized in that an intermediate horizontal portion concentric with the central axis of the center cone is provided at the joint between the lower divided cone member and the upper divided cone member. The vertical crusher according to claim 9,
The intermediate horizontal portion is constituted by an upper portion of the lower divided cone member and a lower portion of the upper divided cone member, and a connecting / separating portion for connecting or separating the lower divided cone member and the upper divided cone member. A vertical crusher characterized in that The vertical crusher according to claim 9 or 10,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The ratio (d3 / d5) of the diameter d3 of the intermediate horizontal portion to the inner diameter d5 of the pulverized raw material supply pipe when the diameter of the intermediate horizontal portion is d3 and the inner diameter of the pulverized raw material supply pipe is d5 is as follows. A vertical crusher characterized by being regulated by the above.
0.5 ≦ d3 / d5 ≦ 1.5 The vertical crusher according to any one of claims 1 to 11,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The circumferential side plate of the upper divided cone member with respect to the inner diameter d5 of the pulverized raw material supply pipe when the lower end diameter of the circumferential side plate constituting the upper divided corn member is d2 and the inner diameter of the pulverized raw material supply pipe is d5. A vertical crusher characterized in that the ratio (d2 / d5) of the lower end diameter d2 is regulated within the following range.
0.4 ≦ d2 / d5 ≦ 1.0 The vertical crusher according to any one of claims 1 to 12,
A vertical crusher characterized in that an upper horizontal portion concentric with the center axis of the center cone is provided on the top surface of the uppermost divided cone member disposed on the uppermost side of the center cone. The vertical crusher according to claim 13,
A pulverized raw material supply pipe for charging the material to be crushed is connected above the center cone,
The diameter d1 of the upper horizontal portion of the upper divided cone member with respect to the inner diameter d5 of the pulverized raw material supply pipe when the diameter of the upper horizontal portion of the uppermost divided cone member is d1 and the inner diameter of the crushed raw material supply pipe is d5. The ratio (d1 / d5) is regulated within the following range.
0.05 ≦ d1 / d5 ≦ 0.2 A vertical crusher;
A coal supply pipe for charging coal to be crushed from the top of the vertical crusher;
In the pulverized coal production apparatus provided with the pulverized coal feeding pipe for feeding the pulverized coal generated by pulverization with the vertical pulverizer to the pulverized coal supply destination,
The pulverized coal production apparatus, wherein the vertical pulverizer is the vertical pulverizer according to any one of claims 1 to 15. In the pulverized coal manufacturing apparatus according to claim 15,
A throat is provided around the crushing table of the vertical crusher,
Classification means having a recovery hopper is provided above the grinding table,
Blowing up the coal particles pulverized at the biting portion of the pulverization table and the rolling pulverization member to the upper classification means side with the conveying gas introduced from the throat,
The pulverized coal production is characterized in that the particle group is divided into pulverized coal and coarse particles by the classifying means, and the coarse particles are dropped from above the center cone through the recovery hopper and pulverized again. apparatus. Pulverized coal production equipment,
In a coal-fired boiler plant equipped with a coal-fired boiler device that introduces and burns pulverized coal produced by the pulverized coal production device,
The coal-fired boiler plant, wherein the pulverized coal production apparatus is the pulverized coal production apparatus according to claim 15 or 16.

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