JPS61197053A - Pressure collapsing type crushing and drying apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a crushing type crushing drying device such as a vertical mill for cement raw materials and blast furnace slag, and particularly relates to a crushing type crushing drying device for cement raw materials, blast furnace slag, etc. The present invention relates to a crushing type crushing and drying device that efficiently crushes and dries solid substances.

(Prior art) Among conventional devices of this type, there is an external circulation type crushing device that allows solid materials to fall through a gap provided around a round table and returns it to near the rollers on the round table using a bucket elevator or the like. be. This conventional device increases the speed of gas passing through the gap from below to above in order to prevent solid substances from falling through the gap around the round table.
Although it has already been demonstrated that the power required for the exhaust gas fan is extremely small, even with this conventional device, it is difficult to crush and dry solid materials containing a large amount of moisture, solid materials containing large lumps, or when the hot air temperature is When the temperature is low, a large amount of hot air is required or the temperature must be raised, which is not yet sufficient in terms of reducing the required power.

In other words, in this type of device, the gas passes from the bottom to the top of the gap around the round table, and if the gap width and the size of the air classifier are constant, there are many hot air walls (the more the pressure loss If the gap width were to be changed according to the hot air wall, the casing would be correspondingly larger, and the air classifier installed above the round table would also have to be larger ( Also, when pulverizing and drying solid materials containing large lumps, the rollers are not sufficiently bitten and the progress of pulverization and drying is delayed, which only unnecessarily increases the amount of material that circulates between the pulverizer and the bucket elevator. As a result, the gas temperature did not rise sufficiently, and the crushing and drying capabilities remained low.

(Problems to be Solved by the Invention) The present invention solves the problems of the conventional apparatuses described above, that is, increases the required power when crushing and drying solid materials containing high moisture content and large lumps. By solving problems such as problems that are unavoidable or that the entire device becomes large, the required power can be reduced, the entire device can be downsized, and the pulverization and drying efficiency can be increased, even for solid materials. It is an attempt to do so.

(Means for Solving the Problems) Therefore, the present invention provides a pulverizing and drying chamber in which a solid substance containing moisture is supplied onto a rotating round table and is brought into contact with hot air, crushed and pulverized with a plurality of rollers or balls, and dried. In a crushing type crushing and drying device equipped with a circulation mechanism that circulates the relatively coarse particles that have fallen from the round table top again using a transporter, a pre-drying device for solid substances is installed before the crushing drying device. A device or a preliminary crushing drying device is provided as a means for solving the above-mentioned problems.

(Function) A solid substance containing a large amount of moisture or a solid substance containing large lumps is first (crushed) dried in a preliminary (crushing) drying device, and the crushing type crushing device in the next step is used to obtain optimal powder production efficiency. It is processed to such a state that it becomes pulverized, and then it is pulverized using a conventional crushing type pulverizer.

(Example) Hereinafter, a crushing type crushing device which is an example of the present invention will be explained based on the drawings. 1 is a crushing type crushing drying device which is the main part of the present invention, and its configuration is such that a horizontal surface is moved by a drive device 9. A rotating round table 2, a roller 5 for crushing and crushing the solid material supplied onto the round table 2 by a chute 4, and a shaft 7 that rotatably supports the solid substance, and the roller 5 rotates as the round table 2 rotates. It rotates and is pressed onto a round table.

A crushing drying chamber 3 surrounded by a casing 6 is installed above the round table 2, and around the lower part of the round table 2, hot air from below is passed through a gap 8 around the round table 2 to the crushing drying chamber 3 above. An air chamber 10 for blowing up the air is installed. 13 is a rotary blade for classifying the powder carried by the upward jet from the peripheral gap 8 of the round table 2.
The air classifier 13 is provided with a gas discharge port 12 on the upper side thereof, and from the discharge port 12, powder together with the gas is collected in a cyclone 14. Gas is also exhausted from the fan 15.

The solid material that has fallen into the lower air chamber 10 is discharged from the discharge passage 17 and falls onto a conveyor 18 that is connected to a bucket elevator 19 . Up to this point, there is essentially no difference from conventional equipment. Reference numeral 20 denotes a preliminary crushing drying device, which is another main part of the present invention, and is composed of a rotary hammer 21 and a liner 22 facing it.Flaps for gas sealing are provided above and below the preliminary crushing drying device 20. Dampers 23,24 are provided. Note that 25 is a cyclone, and 26 is a fan.

The operation will be explained below. The solid material containing moisture is passed through the upper flap damper 23 to the preliminary crushing drying device 20.
supply to. This is a device that can process solid materials even if their size is several hundred. Here, the hammer 21 is rotating at high speed, and the solid material is struck by the hammer 21 and collides with the liner 22, and is crushed into pieces of 20 pieces or less. Meanwhile, hot air is drawn by fan 26 and passes through pre-crush dryer 20 to dry the solid material. Here, the drying does not need to be complete, and it is sufficient that the drying is completed in the crushing type crushing dryer 1 in the next step. In addition, crushing in the preliminary crushing drying device 20 is also carried out using the hammer 2.
1. Considering wear of the liner 22, power consumption, etc., 10~
It is preferable to limit the amount to about 20 fl.

Since the gas discharged from the preliminary crushing and drying device 20 contains fine particles, it is separated by the cyclone 25. The solid material is also sent to the packet elevator 19 via the flap damper 24. Particles collected by the cyclone 25 are also sent to the bucket elevator 19 at the same time. These solid substances are then transported by a packet elevator 19, passed through a chute 4, and are supplied approximately to the center of the round table 2, which is rotated by a drive device 9. The solid substance is rotated by the friction force of 20 revolutions of the round table, and is moved toward the outer periphery of the round table 2 by centrifugal force, reaches the lower part of the roller 5, is bitten, and is crushed and crushed. Therefore, the particle size of the solid substance mentioned earlier is a preferable value for the roller 5 diameter (1 m or more) used in a practical machine, and from this point of view, the necessity of the preliminary crushing drying device 20 is also explained. is to be understood.

The material to be crushed that has reached the outer periphery of the round table 2 is attracted by the fan 15, passes through the air chamber 10, and is blown upward by the gas jetted upward through the gap 8 around the round table. It is sent to machine 13, but the rest is blown back to the center of round table 2.

Moreover, coarse particles cannot be carried by the gas flow, fall into the air chamber 10, and are discharged to the outside of the crushing type crushing dryer 1 through the discharge passage 17.

The fine powder sent to the air classifier 13 is caused by the rotary blades 11, and the coarse powder is thrown off to the casing 6 and returned to the crushing and drying chamber 3 again. It passes through the outlet 12, is collected by the cyclone 14, and is taken out of the system as fine powder.

In addition, the amount of hot air guided to the crushing type pulverizing dryer 1 is preferably the amount necessary to convey and classify the fine powder to the air classifier 13. If it is in excess, the power of the fan 15 will be increased, For example, the amount of fine powder reaching the air classifier 13 is reduced,
This is not preferable because it also reduces the crushing ability.

Therefore, the drying of the solid substance in the preliminary crushing and drying device 20 is carried out to such an extent that the amount of hot air required for drying the solid substance in the crushing type crushing and drying device 1 is approximately equal to the amount of air required for the air classifier 13. It is sufficient to keep the moisture content. It is undesirable to dry more or less than that because it requires more power and makes the device thicker. The coarse solid material discharged through the discharge path 17 is also transferred to the conveyor 1.
After passing through the packet elevator 19 and chute 4, it is returned to the center of the round table 2.

Although not shown in the figure, when crushing, pulverizing, and drying not a single-component solid substance but a substance consisting of multiple components with significantly different particle sizes, some components may be directly crushed and pulverized as necessary. A separate supply device may also be provided to supply the drying device 1.

Furthermore, among the solid substances discharged from the preliminary crushing and drying device 20, those with a large particle size may be returned to the preliminary crushing and drying device 20 again by another transportation device and crushed again as a modification of the present invention. This is desirable.

Below is a table comparing examples of the present invention and conventional examples.

Maximum particle size 150tm containing 15% moisture, 100m sieve 2
To crush cement raw material containing 0% lumps to 15% on an 88μ sieve and 0.5% moisture using a crushing type crushing dryer,
A comparison between the case of carrying out the present invention and the case of processing using only a crushing type pulverizing and drying device is as follows.

Gas inlet temperature ('C) 300 Isopressure preliminary crushing dryer 1, 540
Exit style! (Nnf/l) Same log gas temperature 'C85 Pressure loss (mAq) 200
Pre-crushing dryer 1.1 electric power (
KWH/t”) Fan power (KWH/l) 2
．． 1 Logus temperature ℃85 85Pressure loss (f
lAq) 1.132 620 fan power (KWH/l) 19.6 2.
9 Classifier, transporter etc. 1.2 1.2 Other power (KWH/l) Total power (XwH/l) 28 1
2.3 Furthermore, by implementing the present invention, the crushing and drying capacity was increased by 13% compared to the conventional equipment.

(Effects of the Invention) As described above in detail, according to the present invention, even if a preliminary crushing drying device is added, the total amount of electric power can be greatly reduced, and therefore the required power can be reduced. Furthermore, even when pulverizing and drying solid materials containing large amounts of moisture and large lumps, there is little pressure loss (efficient pulverization is possible, and the pulverizing and drying capacity is significantly improved compared to conventional equipment). It became possible to do so.

[Brief explanation of drawings]

The drawing is a system diagram of a crushing type crushing and drying apparatus showing an embodiment of the present invention. Explanation of the main parts of the diagram 1 - Crushing type crushing dryer 20 - Preliminary crushing dryer 21 - Hammer 22 - Liner 23, 24 - Flank damper

Claims (1)

[Claims] A pulverizing and drying chamber where a solid material containing moisture supplied onto a rotating round table is brought into contact with hot air, crushed and pulverized using a plurality of rollers or balls, and dried, and relatively coarse particles falling from the round table are returned to the circular table A crushing type pulverizing drying device equipped with a circulation mechanism for circulating circulation to a tabletop using a transporter, characterized in that a pre-drying device for solid substances or a pre-crushing drying device is provided upstream of the pulverizing drying device. Grinding and drying equipment.