JP2015112568A - Impact type mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact type mill in which sticking and depositing of a milling object of solid fuel having a high sticking property, to and on a cage part can be prevented or suppressed.SOLUTION: The impact type mill is provided which includes: a pair of rotors 12L and 12R that rotate in directions inverse to each other in a casing; and a plurality of cage bars 21L and 21R that are provided in the rotors respectively and rotate in directions inverse to each other on concentric circles having different diameters, and which mills between the rotating cage bars 21L and 21R, a solid milling object charged in the casing. The rotors 12L and 12R respectively include discs 13L and 13R oppositely arranged at a predetermined interval, and the cage bars are each supported in such a way that they can autorotate with a plurality of cage pins each projected in the rotor axial direction from an opposed surface of the discs as rotation axes.

Description

  The present invention relates to an impact type pulverizer applied to pulverization of a solid pulverized material having high adhesion, such as solid fuel such as lignite and coal residue fuel.

In recent years, lignite and coal residue fuels have attracted attention as promising energy sources in the future. Since such lignite and coal residue fuel are solid fuels with high adhesion properties, as disclosed in, for example, Patent Documents 1 and 2 below, friction materials used for pulverizing ordinary coal and the like are used. Instead of a crushing crusher, a so-called impact crusher is employed.
For example, as disclosed in Patent Document 3 below, the impact-type pulverizer is configured to pulverize a solid pulverized product by applying an impact force to a plurality of cylindrical members (cage bars) provided in a squirrel-cage rotor. It is. In this case, it has been proposed to project a centrifugal fan blade on the outer surface of the side plate in order to prevent the crushed material from depositing and adhering to the inner surface of the side wall of the casing.

JP 2011-214816 A JP 2011-214818 A JP-A-9-122515

By the way, the above-described conventional impact type pulverizer has a plurality of cage bars that are provided in the rotor and rotated in the opposite directions on concentric circles with different diameters, in a casing in which a pair of rotors rotate in opposite directions. It is structured to pulverize the solid pulverized material. In this case, the cage bar for pulverizing the solid pulverized material is attached in a state of being fixed to the disk of the rotor.
For this reason, when solid fuel with high adhesion, such as lignite or coal residual fuel, is crushed, the fuel adheres to the cage due to the moisture contained in the solid fuel and the softening point of the fuel. It becomes a problem. That is, since the cage bar itself is fixed, solid fuel with high adhesion adheres to the outer surface of the cage bar, and this accumulates to deteriorate the pulverizability.

Against this background, in impact-type crushers, even when solid fuel with high adhesion is pulverized, the pulverized material is prevented from adhering to the cage and accumulating to ensure stable pulverization performance. It is desirable to do.
The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide an impact type capable of preventing or suppressing the pulverized product of highly adherent solid fuel from adhering to and depositing on a cage portion. It is to provide a crusher.

In order to solve the above problems, the present invention employs the following means.
The impact-type pulverizer according to the present invention is configured such that a solid pulverized material is charged into a casing in which a pair of rotors rotate in the opposite direction, and a plurality of cage bars provided in the rotor and rotated in the opposite directions on concentric circles having different diameters. In the impact-type pulverizer for pulverizing the solid pulverized product, the rotor includes a disk opposed to the disk at a predetermined interval, and the cage bars protrude from the opposing surface of the disk in the rotor axial direction. A plurality of cage pins are supported so as to be able to rotate about a rotation axis.

  According to such an impact type pulverizer, the rotor is provided with a disk opposed to each other at a predetermined interval, and the cage bar has a plurality of cage pins each protruding in the direction of the rotor axis from the opposite surface of the disk. Since each is supported so as to be able to rotate, the cage bar can rotate and be wiped off every time the solid pulverized material adheres, even when handling a solid pulverized material with high adhesion.

  According to the above-described impact type pulverizer of the present invention, the cage bars each have a structure capable of rotating, and therefore, even if solid pulverized material with high adhesion adheres, it can be removed by the rotation of the cage bar. As a result, accumulation of solid pulverized material can be prevented or suppressed. Therefore, it is possible to provide an impact type pulverizer capable of preventing a decrease in pulverization performance due to the adhering solid pulverized material adhering to and depositing on the cage portion and maintaining stable pulverization performance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment of the impact-type crusher which concerns on this invention, (a) is explanatory drawing which dispels solid crushed material with strong adhesiveness by rotation operation | movement (autorotation) of a cage bar, (b) is (a). It is sectional drawing which shows a cage bar structure. It is a principal part sectional front view showing an outline of an impact type crusher concerning the present invention. It is an enlarged view which shows the cage part of the impact type crusher shown in FIG. It is sectional drawing (AA cross section of FIG. 3) which shows the structure of a cage part. It is a figure which shows the structural example of the lignite-fired boiler provided with the fluidized-bed drying equipment as an application example of the impact-type crusher which concerns on this invention.

Hereinafter, an embodiment of an impact pulverizer according to the present invention will be described with reference to the drawings.
1-4, for example, as shown in FIG. 5, the impact type pulverizer 10 is applied to a lignite-fired boiler 50 that operates using lignite, which is a solid fuel with high adhesion, as fuel. The lignite-fired boiler 50 includes a furnace 51 installed in a vertical direction, a combustion device 52 installed in a lower part of the furnace wall of the furnace 51, a flue 53 connected to an outlet of the furnace 51, and a flue 53 A plurality of superheaters 54, a economizer 55, an induction fan 56 provided on the downstream side of the flue 53, and a chimney 57 are provided.

The combustion device 52 includes a plurality of pulverized coal burners 58 attached to a furnace wall, an impact pulverizer 10 that converts pulverized coal to be supplied to the pulverized coal burner 58, and secondary air ( Air supply means 60 for supplying air).
The impact-type pulverizer 10 pulverizes supplied lignite into pulverized coal having a size suitable for combustion (for example, several μm to several hundred μm), and low temperature combustion from the downstream side of the economizer 55. A part of gas is introduced and dried and pulverized. The impact-type pulverizer 10 is supplied with product charcoal that has been previously dried by the fluidized bed drying equipment 70. Reference numeral 61 in the figure denotes a forced draft fan (air supply device) that pressurizes and supplies air, 62 is a wind box, 63 is a turbine facility, 64 is a condenser, and 65 is a generator.

  In the impact type pulverizer 10 of this embodiment, as shown in FIGS. 1 to 4, a pair of left and right rotors 12L and 12R housed in a casing 11 are rotated in opposite directions by dedicated electric motors 30L and 30R, respectively. The lignite (solid pulverized material) introduced from the mouth 11a is pulverized in the cage portion 20. The cage portion 20 is a space region formed by the rotors 12L and 12R.

  As shown in FIG. 3, the rotors 12L and 12R include disks 13L and 13R that are arranged to face each other with a predetermined interval. The discs 13L and 13R are provided with rotor shafts 14L and 14R. The rotor shafts 14L and 14R and the output shafts of the motors 30L and 30R are connected via pulleys and drive belt mechanisms 31L and 31R. Yes. The axis centers of the rotor shafts 14L and 14R are on the same straight line.

  In addition, a plurality of cage bars 21L, 21R rotating in opposite directions on concentric circles having different diameters are alternately provided in the disks 13L, 13R in the radial direction with appropriate intervals so as not to interfere with each other. The cage bars 21L and 21R project from the facing surfaces of the disks 13L and 13R in the direction of the rotor shafts 14L and 14R, in other words, in a direction parallel to the rotor shafts 14L and 14R.

That is, the cage bars 21L, 21R are configured to alternately rotate in a reverse direction on a plurality of concentric circles having different radii in the space of the cage portion 20 formed between the disks 13L, 13R. Accordingly, the lignite charged from the charging port 11a is introduced into the cage portion 20 and is therefore subjected to an impact between the adjacent cage bars 21L and 21R due to a collision with the cage bars 21L and 21R that rotate in the opposite direction. And then crushed.
In the illustrated configuration example, the cage bars 21L and 21R are arranged in three rows in the radial direction, but are not particularly limited with the number of arrangement in the circumferential direction, and may be appropriately selected according to various conditions. .

  Each of the cage bars 21L and 21R of the present embodiment is attached so as to be able to rotate. Below, based on FIG. 1 (a), (b), the structure which the cage bars 21L and 21R can rotate is demonstrated concretely. The cage bars 21L and 21R are basically the same in structure, although there is a difference between left and right. Therefore, in FIGS. 1A and 1B, symbols that do not give L and R that distinguish left and right are used. I will explain.

  As shown in FIG. 1B, the same number of cage pins 22 as the cage bars 21 project from the opposing surface of the disk 13 in the direction of the rotor axis, and each cage bar 21 is supported so as to be rotatable about the cage pins 22 as a rotation axis. Yes. In the illustrated configuration example, for example, a sliding bearing 23 is appropriately interposed between the cage bar 21 and the cage pin 22 in order to facilitate the rotation of the cage pin 22.

  The cage bar 21 configured in this manner sequentially interferes with the lignite charged in the cage portion 20 as the rotors 12L and 12R rotate in the reverse direction. By repeating such interference, an impact force that is sandwiched between the cage bars 21 from both sides in the cage bar rotation direction is repeatedly applied to the brown coal in the cage portion 20. As a result, the lignite in the cage 20 part is crushed and pulverized by impact force and discharged to the outside of the cage part 20.

  If such pulverization is continued, since lignite is a solid fuel with high adhesion, the deposit 1 is deposited on the outer surface of the cage bar 21 as shown in FIG. The deposit 1 can be removed.

  That is, as shown in the left end of FIG. 1 (a), when the deposit 1 is deposited on the surface of the cage bar 21, the cage bar 21 is moved by the center of gravity of the cage bar 21 or the interference between the protruding portion of the deposit 1 and brown coal. A rotational force is generated and rotates in either direction around the cage pin 22. As a result, a force in the direction of peeling the deposit 1 from the surface of the cage bar 21 acts on the deposit 1, and therefore the deposit 1 is removed without being deposited. In addition, as a specific example of the force which peels off the deposit | attachment 1, there exist the interference of the deposit | attachment 1 adhering to the centrifugal force by rotation, the adjacent cage bar 21, etc., for example.

According to the impact type pulverizer 10 of the present embodiment described above, the cage bars 21L and 21R each have a structure capable of rotating, so even if a solid pulverized material such as highly adherent lignite adheres, the cage bar It becomes possible to pay off by the rotation of 21L and 21R. As a result, the impact-type pulverizer 10 can prevent or suppress the solid pulverized material having high adhesion from being deposited as the adhered material 1, so that the adhered material 1 is deposited on the cage bars 21 </ b> L and 21 </ b> R in the cage portion 20. It is possible to prevent the resulting pulverization performance from being lowered and maintain stable pulverization performance.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary, it can change suitably.

DESCRIPTION OF SYMBOLS 10 Impact type crusher 11 Casing 11a Slot 12L, 12R Rotor 13L, 13R Disc 14L, 14R Rotor shaft 20 Cage part 21, 21L, 21R Cage bar 22 Cage pin 23 Sliding bearing 30L, 30R Electric motor 31L, 31R Pulley & drive belt mechanism

Claims (1)

An impact type in which a solid pulverized material is charged into a casing in which a pair of rotors rotate in the opposite direction, and the solid pulverized material is pulverized between a plurality of cage bars provided in the rotor and rotating in opposite directions on concentric circles of different diameters. A crusher,
The rotor includes a disk disposed oppositely with a predetermined interval,
The impact type pulverizer, wherein the cage bar is supported so as to be capable of rotating about a plurality of cage pins each protruding in the rotor axial direction from the opposing surface of the disk.

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