JP3036904B2 - Method for treating object to be treated using fluidized bed and fluidized bed - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
In the steel industry, chemical industry, chemical industry and incineration field,
The present invention relates to a fluidized bed in which particles are suspended and processed (reaction, drying, mixing, liquid coating).

[0002]

2. Description of the Related Art In general, when particles handled in a fluidized bed have a certain particle size, the minimum fluidization speed is different. It is necessary to appropriately determine the size of the particles to be formed. Fortunately, for a given particle size, there is a significant range between the minimum fluidization rate and the terminal velocity of the particles, which makes it necessary to fluidize the entire particle population, even if the particle size distribution is wide. Can be. In particular, when there are many fine particles, a function as a fluidized bed is not impaired by attaching a cyclone or the like to the upper part of the fluidized bed to collect and recirculate the fine particles. It is generally empirically known that particles in the range of one tenth smaller than the average particle diameter or ten times larger than the average particle diameter can be sufficiently processed by the conventional technology.

[0003]

The problem here is that natural products, such as underground reserves such as ore and coal, and solid waste which has been widely handled recently, have a very large particle size distribution. If the material is wide and contains foreign matter (stones, wood chips, plastics, metal, shards, etc.), it is necessary to treat it because it is as large as 100 to 1000 times the average particle size. .

In handling such materials, a sieve is provided in front of the fluidized bed to separate coarse particles, and the coarse materials can be achieved by pulverizing them. If the material is intentionally pulverized, or if a sieve is used, most of the powder must be recovered under the sieve, so that the size of the sieve becomes large and is not economical.

On the other hand, when such a mixture is put into a fluidized bed without sieving, it is quite obvious that what is not fluidized is deposited on the dispersion plate of the fluidized bed, and the fluidized bed is formed. Stop functioning. It is difficult to cope with such a situation with a conventional fluidized bed. The nozzles for fluidization that have been conventionally considered to be the best are as follows, but none can be processed smoothly. That is,

(A) In the case where a nozzle called a machine hat 2 is provided so as to protrude from the dispersion plate 1 (see FIG. 8), there is a problem that coarse particles are caught by the machine hat 2 and cannot flow. .

(B) In the case of the dispersion plate 1 in which the through holes 3 are formed (referred to as a perforated plate, see FIG. 9), it can be transported relatively well, but the sticky one has no holes. The coarse particles are deposited on the flat plate, and the coarse particles cannot flow with a vertical force.

(C) In the case where the V-shaped plate 4 is connected to the dispersion plate 1 (see FIG. 10), back spin is applied to the blowout from the nozzle, and vortices are formed on the dispersion plate 1 so that they are transported. In addition to causing a decrease in capacity, the sticky substance adheres to the flat plate.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a processing target such as a reaction, drying, incineration or the like in which a large aggregate unlike a normal particle size distribution is formed. Suitable for processing substances with irregular particles, such as those in or abnormally shaped, i.e. particles with a normal size distribution can be operated in a fluidized state and particles of an abnormal size An object of the present invention is to provide a fluidized bed that can control the residence time in a fluidized bed while rolling the bottom portion, and that can smoothly and reliably process the fluidized bed.

[0010]

According to a first aspect of the present invention, there is provided:
The processing method depends on the gas ejected from the nozzle.
Of treatment of objects using a fluidized bed for treating objects
The object is 100 to 1000 times the average particle size.
Qi be those containing coarse particles of particle size, ejection direction of the gas ejected from the nozzle, is set obliquely upward and in the conveying direction of the object Rutotomoni, from the nozzle
When the blowing speed of the body is set to 40-50 m / sec
The coarse particles of the object to be treated are treated with the gas.
Rolling and processing.

[0011]Also,Claim 2 of the present inventionFluidized bed related to
IsA fluidized bed used in the processing method according to claim 1.
Therefore, a jump table is located on the distribution plate with the air inlet formed.
By being laid,Is the nozzle close to the nozzle
With an inclined surface for guiding the gas ejected from the
You.

[0012]

According to the processing method of the first aspect of the present invention, the injection is performed at a blowing speed of 40 to 50 m / sec from a nozzle set in the transfer direction of the processing object and obliquely upward. > Due to outgassing, there is no average particle size of 100
Those having a large particle diameter of 1000 times are transported while rolling mainly on the bottom, and those having a small particle diameter exhibiting a normal distribution are smoothly fluidized and transported. here
So that the blowing speed is less than 40 m / sec.
When rolling, large particles with large particle diameters are reliably rolled.
While it may not be possible to transport
Conversely, it increases as the blowing speed exceeds 50 m / sec.
And maintain particles with a normal distribution in the proper flow state
There is a possibility that the operation cannot be performed.

[0013] In the fluidized bed according to the second aspect of the present invention, the direction of the gas ejected from the nozzle is properly controlled by the inclined surface, and the rolling of the solid having a large particle diameter is guided. . And, this inclined surface is formed by the air inlet.
Formed by laying a jumping platform on the scattering plate
Production of these dispersion boards and jumping hills
It is easy and the rigidity of the dispersion plate in the
And large particles having a large particle size can be obtained.
Even if rolling on the dispersion plate, the dispersion plate may be bent.
Can be prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In FIGS. 1 and 2, reference numeral 10 denotes a fluidized bed main body. The fluidized bed main body 10 has a bottom plate 11 and a top portion 12 fixed by side plates 13. A dispersion plate 14 is attached inside the fluidized bed main body 10, and a space between the dispersion plate 14 and the bottom plate 11 is a pressurizing chamber 15. An air inlet 16 is provided. Further, a flow air outlet 17 is provided on the top portion 12, and a powder inlet 18 and a powder outlet 19 are attached to a pair of opposed side plates 13, respectively.

As shown in FIG. 3, the dispersion plate 14 includes:
An air inlet 20 is formed in the dispersion plate 14, and a semi-cylindrical cap 21 is provided above the air inlet 20 in the powder transfer direction (the direction from the powder inlet 18 to the powder outlet 19). And these caps 2
In between, a jump table 22 is provided obliquely upward toward the powder transfer direction, and
In addition, nozzles 23 are formed at appropriate intervals in a direction along the inclined surface 24 of the jump table 22. FIG. 4 shows another example of the dispersing plate 14.
Is laid.

When handling a large amount of powder, the planar shape of the fluidized bed is preferably elliptical or square. Of course, a round shape can be moved sufficiently. In addition, it is necessary to carefully select the mounting angle on the dispersion plate, the width of the dispersion plate, the height of the cap, the shape of the cap, and the like.

In the fluidized bed configured as described above, the average particle size is 100 to 1000 times as described above.
Of underground reserves such as ore and coal containing coarse particles of
A powder containing an elliptical solid having a remarkably different particle size distribution, such as a solid waste containing natural products or foreign substances , is supplied into the fluidized bed from the powder inlet 18 and the flowing air is used for fluidization. Flow air outlet 17 introduced from air inlet 16
Is more exhausted. Then, the flowing object is discharged out of the fluid layer through the powder outlet 19.

Here, the inside of the fluidized bed will be described in more detail. Large particles, for example, 25 to 50 m
The m m or the like rides on the jump tables 22 and 25 on the dispersion plate 14 and moves upward by the air jetted from the nozzle 23. That is, the large-diameter particles move from the inlet side to the outlet side according to the entire flow at the bottom due to the rolling and slight flow state. On the other hand, small particles with a normal distribution
The fluid flows freely, proceeds from the inlet to the outlet, and is discharged to the outside, while fluidizing at an appropriate fluidizing speed by the blown air at a corresponding particle concentration.

Then, it is ejected from the nozzle 23
The air blowing speed is 40-50 m / sec.
Therefore, the velocity of the air received by the coarse particles depends on the nozzle 23
Since the air that has been blown out hits the coarse particles as it is, it is 40 to 50 m / sec. However, the air received by the small-sized particles having a normal distribution is dispersed by the coarse particles rolling on the lower side, and is uniformly supplied to the upper particle fluidized bed. In this case, the apparent fluidization speed is about 2.0 to 4.5 m / sec. That is, in the fluidized bed of the present invention, 40 to 5
It is characterized in that particles are moved by a jet flow obliquely upward at 0 m / sec, and normal particles are fluidized by a vertical flow at a normal appropriate fluidizing speed. Here, the gas from the nozzle 23 is
If the blowing speed is lower than 40m / sec,
It is no longer possible to reliably roll and transport the coarse particles.
While the blowing speed exceeds 50m / sec.
The larger the number of particles, the larger the number of small particles with a normal distribution.
Is discharged together with the flowing air from the flowing air outlet 17.
Is circulated in the fluidized bed body 10
The flow state may not be maintained properly.
is there.

In this regard, there are many structures having a structure in which a jet stream is emitted horizontally. However, in order to move particles having a large particle diameter in a horizontal direction, the jet stream blown from a nozzle is directed to a dispersion plate. It is necessary to hit the coarse particles without forming a vortex, and for that purpose, the angle and length of the inclined surface 24 of the jump tables 22 and 25 have an important purpose. That is, when the jet stream is caused to flow in parallel on the dispersion plate without the jump tables 22 and 25, the backspin is applied, the motion of the air stays, and the moving speed of the elliptical particles becomes slow. Moreover, this inclined surface 24 is
Plate 14 in which the air inlet 20 is formed as described above,
Laying the cap 21 on which the
22 is provided at an angle, or a nozzle 23 is formed.
By laying a jumping cross 25 with a rectangular cross section
The dispersion plate 14 itself is flat as in the prior art.
It is formed in a plate shape, and a cap 21
What is necessary is just to lay 22 and 25, these dispersion plate 14 and inclination
The production of the surface 24 is easy and the dispersion plate 14
Rigidity, and coarse particles are formed on the dispersion plate 14.
Prevents the dispersion plate 14 from bending or the like even when rolling.
be able to.

Example 1 A raw coal having a particle size distribution shown in FIG. 7 was put into a conventional fluidized drier having a width of 400 mm and a length of 2.5 m to perform a fluidization test. The aperture ratio of the used dispersion plate was 7%, and the hole diameter was 8 mm. The operation was performed at a feed rate of 2.5 tons / hr and a stationary layer height of 400 mm. Then, the pressure loss at the beginning of the operation was 200 mmAq, and the fluid flowed over the entire surface for 15 minutes. However, the pressure loss became 350 mmAq after 1 hour, the range of the non-flowable layer was about 20%, and the particles at the outlet were Only small ones. When the supply was further continued, the pressure loss became 400 mmAq after 2 hours, and the non-fluidized area was 70 mmAq.
%, The powder surface was inclined, and the powder was moved according to the inclination (see FIG. 5). Inside the accumulated powder layer,
Large sized particles remained stagnant and then became inoperable.

On the other hand, using the same fluidized bed, the dispersion plate portion was modified to the structure of the present invention, and the length of the jump table was 60 mm.
As a result of operating under the conditions of an angle of 5 °, a cap height of 15 mm, and an opening ratio of 7% at a nozzle blowing speed of 40 m / sec and under the same supply conditions as described above, stable continuous operation is performed for a long time. During this time, no stagnation was observed in the fluidized bed (see FIG. 6), and the particle size distribution of the feed and that of the discharge were almost the same.

[0024]

As described above, according to the first aspect of the present invention,
In the processing method according to, ejection direction of the gas ejected from the nozzle, is set obliquely upward and in the conveying direction of the object Rutotomoni, blowing velocity of the gas from the nozzle
Is set to 40 to 50 m / sec, and the average particle diameter of the object to be processed is set to 1 by the gas ejected from the nozzle set in the transfer direction of the object and obliquely upward.
Coarse particles having a particle diameter of 00 to 1000 times perform a smooth horizontal movement while being reliably rolled on the fluidized bed dispersion plate, so that necessary operations (drying, incineration, heat treatment) can be performed. In addition, particles having a normal particle diameter and a particle size distribution can form a fluidized bed of an appropriate height, so that an appropriate fluidized state can be stably and smoothly maintained, and Can be sufficiently performed.

Further, claim 2 of the present inventionFluidized bed related to
IsA jump stand is placed on the dispersion plate with the air inlet formed.
By being established,From the nozzle close to the nozzle
It has an inclined surface that guides the ejected gas.
From the direction of the gas ejected from the nozzle by the inclined surface
The ability to properly control the properties and ensure the rolling of large solids
Can be guided toAbove, these dispersing plates and inclined surfaces
It can be easily manufactured and large particles roll
The dispersion plate must have sufficient rigidity so that it does not
Can be maintained.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is an enlarged view showing an example of a dispersion plate unit.

FIG. 4 is an enlarged view showing another example of the dispersion plate portion.

FIG. 5 is a state diagram when coal is dried by a conventional fluidized drier shown for comparison.

FIG. 6 is a state diagram when coal is dried by the fluidized dryer of the present invention.

FIG. 7 is a characteristic diagram showing a particle size distribution of raw coal.

FIG. 8 is an explanatory diagram showing a machine hat type nozzle.

FIG. 9 is an explanatory view showing a perforated nozzle.

FIG. 10 is an explanatory view showing a nozzle in which plates are cascaded.

[Explanation of symbols]

 23 Nozzle 24 Inclined surface

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayasu Ito 2--17-15 Tsukushima, Chuo-ku, Tokyo Inside Tsukishima Kikai Co., Ltd. (72) Isao Ogawa 2-17-15 Tsukushima, Chuo-ku, Tokyo Tsukishima Examiner in Machine Co., Ltd. Kazuhiro Kosuge (56) References: Japanese Utility Model Application Sho 57-105595 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F26B 17/10 F26B 21/00

Claims (2)

(57) [Claims] In a method for treating a processing object using a fluidized bed for processing the processing object by a gas ejected from a nozzle, the processing object has an average particle diameter of 100 to 1000 times.
Qi be those containing coarse particles of particle size, ejection direction of the gas ejected from the nozzle, is set obliquely upward and in the conveying direction of the object Rutotomoni, from the nozzle
When the blowing speed of the body is set to 40-50 m / sec
The coarse particles of the object to be treated are treated with the gas.
Using a fluidized bed characterized by rolling and processing
Processing method of the object . 2. A processing method according to claim 1.
In a fluidized bed where the air inlet is formed,
By laying the pump table, an inclined surface for guiding the gas ejected from the nozzle in the vicinity of the nozzle is formed.
Fluidized bed, characterized by that.