JP2000127154A - Method and apparatus for dehumidifying and drying granular material using carrier gas substitution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for dehumidifying and drying a granular material capable of efficiently dehumidifying and drying in a short time with a small size without necessity of a large-size heating mans. SOLUTION: A granular material is stored in a dry hopper 1, and then the stored material is heated or pressure reduced in the state that the hopper 1 is sealed. Thus, a carrier gas regulated at a humidity, a temperature or the like is externally introduced from an inlet 29 into the hopper 1 while generating a miscellaneous gas such as steam, volatile gas or the like, and gas containing the miscellaneous gas is exhausted out of the hopper 1 by a gas exhausting means 27, thereby humidifying and drying the material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for dehumidifying and drying a particulate material using carrier gas replacement, which can efficiently dehumidify and dry the particulate material in a short time.

[0002]

2. Description of the Related Art Conventionally, as a device for dehumidifying and drying a particulate material, a particulate material is stored in a drying hopper, and heated and dried air is passed through the drying hopper to dehumidify and dry the particulate material. A dehumidifying and drying method and apparatus called aeration type have been frequently used. FIG. 6 is a diagram showing an example of such a ventilation type dehumidifying and drying apparatus for a granular material.

The ventilation type dehumidifying and drying apparatus D includes a ventilation type drying hopper 101 for accommodating powder and granular material such as resin pellets to be dried, and a hot air supply means 102 attached to the ventilation type drying hopper 101. , Ventilation type drying hopper 1
01, an air supply pipe 104 connecting between the diffuser cone 103 and the hot air supply means 102, and a ventilation drying hopper 101.
And an exhaust gas recovery pipe 105 that connects between the hot air supply means 102 and the hot air supply means 102.

The ventilation type drying hopper 101 is provided at a central portion of a cylindrical straight body 101a, a conical portion 101b tapering downward and downward, and a central portion of the conical portion 101b. The powdered and granular material which has been stored in the drying process
1 and a discharge pipe 101c discharged from the inside thereof, and an upper portion thereof (top plate)
Material input port 10 provided in the central portion 101e of 101d
1f and a material input port 101 at an upper portion (top plate) 101d thereof
The air outlet 101g is provided on the side of f.

[0005] Material inlet 1 of ventilation type drying hopper 101
Above 01f, a material storage hopper 106 in which the granular material to be dried is stored is provided via a material input valve 107. Also, the ventilation type drying hopper 101
A material transport pipe (not shown) and a material input port (not shown) of a molding machine or the like are connected below the discharge pipe 101c.

The hot air supply means 102 includes a heating means (not shown) for heating and drying the air or the like, and a blowing means (not shown) such as a blower for supplying hot air into the ventilation drying hopper 101. It has. Diffuser cone 10
3. One end 103a is a ventilation type drying hopper 101
Is connected to the air supply pipe 104 connected to the hot air supply means 102 at the side of the straight body 101a of
03b is a discharge pipe 101c of the ventilation type drying hopper 101.
Is provided in the upper central portion near the
03b, an opening 103c for diffusing and supplying hot air supplied from the hot air supply means 102 into the ventilation type drying hopper 101 and a plurality of small holes 103d formed on the outer peripheral surface outside the opening 103c. Is provided.

[0007] The exhaust gas recovery pipe 105 is provided so as to connect between the hot air supply means 102 and the air discharge port 101g provided in the upper portion (top plate) 101d of the ventilation type drying hopper 101. And the hot air supply means 10
The hot air generated from the ventilating hopper 1 through the opening 103c in the lower portion 103b of the diffuser cone 103 and a number of small holes 103d formed in the outer peripheral surface outside the opening 103c.
01 after being diffused and supplied into the inside of the hopper 101,
Air outlet 101 provided in the upper part (top plate) 101d
g, hot air supply means 102 via exhaust gas recovery pipe 105
And is regenerated into hot air that has been dried by the hot air supply means 102, and is circulated and circulated into the ventilation type drying hopper 101.

When a predetermined amount of the granular material is dried using the hopper dryer D, first, the material input valve 107 is opened for a predetermined time and the material storage hopper 1 is opened.
A predetermined amount of the granular material stored in 06 is accommodated in the ventilation type drying hopper 101. Next, the hot air supply means 102
Is operated to blow hot air of a predetermined temperature into the powder material stored in the ventilation drying hopper 101 to dry the powder material stored in the ventilation drying hopper 101. In this ventilation type dehumidifying and drying method, hot air is blown into the granular material, the granular material is heated by the heat of the hot air, and moisture and volatile components of the granular material are taken out through the hot air. It is dehumidified and dried.

The dried granular material is supplied to the material transporting pipe (not shown) from the discharge pipe 101c of the ventilation drying hopper 101 to the discharge pipe 101c, or to a material input port (not shown) of a molding machine. (Not shown).

[0010]

However, in this conventional ventilated dehumidifying and drying apparatus, hot air that has been heated and dried is continuously blown into the particulate material stored in the ventilated drying hopper 101 to heat the air. In addition, since the hot air supply means 2 is used for dehumidifying and drying, the hot air supply means 2 for generating an air volume sufficient to always flow through the hopper 101 is required.
Was larger.

Further, in this conventional ventilation type dehumidifying / drying apparatus, since heating and dehumidifying / drying are performed simultaneously by aeration, it is generally possible to take out moisture and the like from the granular material by hot air in a short time. Despite the fact that heating of the granular material by hot air takes time, there is a problem that the entire processing time is also restricted by the time of hot air heating.

The present invention solves the above-mentioned conventional problems, and provides a method and an apparatus for dehumidifying and drying a powdery or granular material, which do not require a large-sized heating means, can efficiently perform dehumidifying and drying in a short time, and can be downsized. It is intended to be.

[0013]

In order to solve the above-mentioned problems, the present invention proposes a method and an apparatus for dehumidifying and drying a granular material using the inventive concept of replacing carrier gas.
This carrier gas replacement means that heating and dehumidification and drying of the granular material are conventionally treated as a single unit in the ventilation type dehumidification and drying method and apparatus, but the heating and dehumidification and drying are separated. It is characterized by: The dehumidifying drying is performed by replacing a gas containing water vapor and volatile gas and other miscellaneous gases generated by the powder material in the drying hopper by heating or the like with a prepared carrier gas such as humidity and temperature. By doing so. Therefore, this method is called carrier gas replacement.

[0014] Here, in Claims 1 and 2, a method for dehumidifying and drying a granular material using carrier gas replacement is proposed, and in Claims 3 to 6, the apparatus is proposed. In other words, in the method for dehumidifying and drying a particulate material using carrier gas replacement according to claim 1, the powder material stored in a drying hopper is sealed in a dry hopper, and then the stored powder is stored. By heating the granular material, or by performing a reduced pressure treatment, while generating various gases such as water vapor and volatile gas, a carrier gas prepared such as humidity and temperature is introduced from the outside into this drying hopper, The method is characterized in that the particulate material is dehumidified and dried by leading the gas containing the miscellaneous gas to the outside of the drying hopper.

Here, the carrier gas refers to a gas supplied from the outside into the drying hopper, which is set to a predetermined temperature, and is instead a powdery material to be dried,
The humidity is lower than the gas discharged from the drying hopper,
It is desirable that the gas has a low impurity concentration. In addition, the gas is not limited to so-called air and air, and may include a gas such as nitrogen gas as a component in accordance with the dehumidifying and drying mode according to the type of the granular material to be dried.

The heating method is not limited as long as it is not a ventilation method. The decompression treatment refers to reducing the pressure of the drying hopper below the atmospheric pressure, and the degree of decompression, in other words, the degree of vacuum, is appropriately set according to the type of the granular material to be dried and the degree of drying. Is done. When such a carrier gas replacement is used, dehumidification and drying of the granular material can be performed with a carrier gas amount several times as large as the substantial air amount in the drying hopper excluding the volume of the stored granular material material. Compared to a ventilation type dehumidifying and drying apparatus which requires several tens of times the amount of hot air, the amount of gas required for dehumidifying and drying can be greatly reduced, and the apparatus can be downsized. In addition, dehumidification and drying can be efficiently performed in a short time.

According to a second aspect of the present invention, there is provided a method for dehumidifying and drying a particulate material using carrier gas replacement, wherein the particulate material is heated by a heat conduction heating means provided in the drying hopper. The carrier gas is introduced from the outside, and the gas containing the miscellaneous gas is led out of the drying hopper. This method is characterized in that a heat conducting heat means is used as the heating means.

The heat conduction heating means comprises a drying hopper itself made of a heat conductive material,
A partition wall made of the same material is directed toward the inside and extended, and heat from a heating means (a heat source) provided on the outer periphery of the drying hopper is conducted to heat the inside of the granular material. It is characterized by. In other words, by actively using the thermal conductivity of the material, there is no need to provide complicated heating means inside the drying hopper, and the internal structure of the hopper becomes a simple structure with only vertically extending partition walls. Since it utilizes the thermal conductivity of, it is possible to perform gentle and uniform heating. Furthermore, by providing as many partition walls as possible, the heat transfer area for transferring the conductive heat to the granular material is increased, thereby improving the heat transfer efficiency.

According to the method for dehumidifying and drying a powdery or granular material using the carrier gas replacement, the effects of both can be synergistically exhibited by combining with such a heat conduction heating means. An apparatus for dehumidifying and drying a particulate material using carrier gas replacement according to claim 3, comprising a drying hopper for storing and drying the particulate material, and heating for heating the particulate material stored in the drying hopper. Means, an inlet for introducing a carrier gas, such as humidity and temperature, from the outside to the drying hopper, and a gas including miscellaneous gases such as water vapor and volatile gas generated in the drying hopper to the outside. And heating the stored particulate material in a state where the drying hopper is sealed, thereby generating various gases such as water vapor and volatile gas while the drying hopper is closed. The carrier is prepared by introducing a carrier gas adjusted in humidity and temperature from the outside to the outside, and the gas containing the miscellaneous gas is led out of the drying hopper to dehumidify and dry the granular material. To.

This apparatus is provided with only the heating means for the granular material, and in the dehumidifying and drying method according to claim 1, the heating and the carrier gas replacement under atmospheric pressure or positive pressure are combined. This is an apparatus for realizing the dehumidifying and drying method, and can exhibit the effects of the method of the first aspect. An apparatus for dehumidifying and drying a granular material using carrier gas replacement according to claim 4, comprising: a drying hopper for storing and drying the granular material; and a decompression means for reducing the pressure in the drying hopper.
An inlet for introducing a carrier gas, such as humidity and temperature, from the outside into the drying hopper, and a gas discharge for discharging a gas containing miscellaneous gases such as water vapor and volatile gas generated inside the drying hopper to the outside. In the state that the drying hopper is sealed, the stored powdery material is subjected to a reduced pressure treatment to generate various gases such as water vapor and volatile gas, while maintaining the humidity inside the drying hopper. The method is characterized in that a carrier gas prepared at a predetermined temperature or the like is introduced from the outside, and the gas containing the miscellaneous gas is led out of the drying hopper, so that the particulate material is dehumidified and dried.

This apparatus is provided with only the decompression means of the drying hopper, and realizes the dehumidification and drying method of the dehumidification and drying method according to claim 1, which is a combination of decompression and carrier gas replacement. The effect of the first method can be exhibited. An apparatus for dehumidifying and drying a particulate material using carrier gas replacement according to claim 5, wherein a drying hopper for storing and drying the particulate material and a heating device for heating the particulate material stored in the drying hopper are provided. Means and decompression means for depressurizing the inside of the drying hopper, an inlet for introducing a carrier gas prepared from the outside such as humidity and temperature to the drying hopper, and water vapor and volatile gas generated in the drying hopper. Gas discharging means for discharging a gas containing miscellaneous gases to the outside, and by heating and depressurizing the stored granular material in a state in which the drying hopper is sealed, water vapor and volatile gas While generating such miscellaneous gases, a carrier gas adjusted in humidity and temperature is introduced into the drying hopper from the outside, and the gas containing the miscellaneous gases is introduced to the outside of the drying hopper. By,
It is characterized in that the granular material is dehumidified and dried.

This apparatus is provided with both a heating means for the granular material and a depressurizing means for the drying hopper, and in the dehumidifying and drying method according to the first aspect, the heating and depressurizing treatment and the carrier gas replacement are combined. This is an apparatus for realizing a dehumidifying and drying method, and can exhibit the effects of the method of claim 1 more efficiently. According to a sixth aspect of the present invention, in the apparatus for dehumidifying and drying a particulate material using carrier gas replacement, the heating means of the drying hopper is a heat conduction heating means in any one of the third and fifth aspects. I do.

This device is characterized in that the heating means is a heat conduction heating means, the hopper internal structure has a simple structure consisting only of vertically extending partition walls, and utilizes the thermal conductivity of the material. , So that gentle and uniform heating is possible,
The effect of the heat conduction heating means of good thermal efficiency and the effect of the carrier gas replacement are synergistically exhibited.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dehumidifying and drying apparatus for a granular material according to the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an entire configuration of an example of a dehumidifying and drying apparatus for a granular material using carrier gas replacement according to the present invention, and FIG. 2 is a diagram of the dehumidifying and drying apparatus for a granular material according to an embodiment of the present invention. FIG. 2A is an external view of a main body, in which FIG. 2A is a front view partially cut away, and FIG.

The dehumidifying and drying apparatus A shown in FIG. 1 is of a floor-standing type, and comprises a drying hopper 1 provided with a heat conducting wall 2 formed in a cylindrical shape and a heating means 3 provided on the outer periphery thereof. It is installed on a stand 1a, and a roller 1b is provided below the stand 1a so as to be movable. The drying hopper 1 is provided with a nozzle 21, a collector 22, a material input valve 23, and a material discharge valve 24 provided in a material tank or the like. The nozzle 21 sucks the granular material to be sequentially supplied to the drying hopper 1 for dehumidification and drying, and collects the collected material.
2 and the powder material is supplied into the drying hopper 1 by the material input valve 23. In the drying hopper 1, the powder material dried and dehumidified by using the carrier gas replacement is transferred to the lower portion. Is discharged from a material discharge valve 24 disposed in the next step to a resin molding machine or the like which is the next step.

A level gauge (LV) for detecting the amount of the granular material in the hopper is provided in the drying hopper 1.
14, a vacuum pump (VP) 27 for evacuating the hopper is installed on the machine base 1a, and connected to the upper side of the drying hopper 1 by a pipe.
This pipe is provided with a vacuum sensor (P
S) 26, a filter 25 for filtering gas to be sucked, a valve 28 for returning the inside of the drying hopper 1 to atmospheric pressure, and a pressure gauge (PG) 28a for measuring the degree of vacuum or the degree of decompression inside the drying hopper 1 are connected. Have been.

In the dehumidifying and drying apparatus A, the vacuum pump (VP) 27 constitutes a decompression means for generating miscellaneous gases such as water vapor and volatile gas from the granular material, and contains the miscellaneous gas. It also serves as a gas releasing means for guiding the gas inside the drying hopper to the outside. Further, on the lower side, a valve 29a for introducing a carrier gas for replacing the carrier gas and an inlet 29 composed of an adjusting valve 29b for adjusting the amount of introduction are connected. , Material blower (B)
The air blowing side of 30 is connected via a transport switching valve 31.

A transport filter 32 for filtering transport air is connected to the suction side of the material transport blower 30. The transport filter 32 is connected to the transport filter 32 through a switching valve 34.
The transportation exhaust from the resin molding machine or the transportation exhaust from the collector 22, which is the next step, is selectively connected. The machine base 1a is further provided with a control panel 33 for controlling the entire dehumidifying and drying apparatus A.

The internal structure of the drying hopper 1 will be described later. As shown in FIGS. 2A and 2B, the main body of the dehumidifying and drying apparatus for the granular material including the drying hopper 1 is as follows.
A collector 22 is installed at an upper portion of the drying hopper 1 via a material input valve 23, and a collector 22 is provided at a lower portion thereof.
4 are provided. The discharge side of the discharge valve 24 is connected to the blower side of the transport blower 30 via a transport switching valve 31 so as to be able to connect and disconnect.

The above-described vacuum pump (vacuum pump) 27 is disposed beside the transport blower 30.
A transport filter 32 is disposed on the upper side, and a control panel 33 for controlling the entire apparatus is disposed on the upper side. As described above, the dehumidifying / drying apparatus A can be conveniently used at a desired place because the related equipment is compactly mounted on the machine base 1a and can be moved.

In the dehumidifying and drying apparatus A for powder and granular material using the carrier gas replacement, the transport switching valve 31 is switched to open the air blowing side of the transport blower 30, while the switching valve 34 is switched to the collector 22 side. Then, the suction side of the transport blower 30 is connected to the collector 22, and the collector 22 collects the particulate material via the nozzle 21. Next, when the particulate material is charged and stored in the drying hopper 1 from the collector 22 until the level gauge 14 emits a signal, the material charging valve 23 is closed, and the airtightness in the drying hopper 1 is maintained. The powdered granular material is heated by the heating means 3 to heat the stored particulate material, and further, while the inside of the drying hopper 1 is depressurized to a predetermined degree of depressurization by the vacuum pump 27, the depressurized processing of the powdered particulate material is performed I do.

[0032] In this case, the moisture retained in the powder material is generated as water vapor and the volatile component is generated as a volatile gas. At this time, water vapor or volatile gas is generated from the granular material only by heating, but depending on the material, if the material is heated to an excessively high temperature, the material may be degraded. When this is performed, the boiling point of water or the like is lowered, and evaporation and volatilization can be performed at a lower temperature. If necessary, a reduced pressure treatment may be performed in order to promote evaporation and volatilization.

On the other hand, water vapor and volatile gas are generated only by the decompression treatment. However, in the case of powdery material such as resin pellets, the temperature is usually reduced to a predetermined temperature due to the processing requirement of the resin molding machine in the next step. Since it is a condition that it is heated,
In many cases, heating is also performed. In this manner, while generating various gases such as water vapor and volatile gas in the drying hopper 1, in the dehumidifying and drying apparatus A, a carrier gas whose humidity, temperature, and the like are adjusted is introduced from the introduction port 29, and drying is performed at the same time. The gas containing miscellaneous gas of the hopper 1 is sucked out by the vacuum pump 27 and led out of the hopper 1 to dehumidify and dry the granular material.

More specifically, here, normal air is used as the carrier gas, and the adjusting valve 29b of the inlet 29 is adjusted to introduce the outside air. Thus, the gas in the drying hopper 1 is sucked, and a predetermined degree of reduced pressure is maintained by the pressure gauge 28a. As described above, when the dehumidifying and drying is performed using the carrier gas replacement, the dehumidifying and drying of the granular material is performed with the carrier gas amount which is several times the real air amount in the drying hopper excluding the volume of the stored granular material. The amount of gas required for dehumidification and drying can be greatly reduced as compared with a ventilation type dehumidification and drying device which requires hot air of several tens times the actual air amount, and the size of the device can be reduced. In addition, dehumidifying and drying can be efficiently performed in a short time. In addition, a filter, a dryer, a heating means, and the like are provided in front of the inlet 29 to remove dust and the like, and a carrier gas obtained by further heating and drying the atmosphere. Is introduced, it is possible to more effectively dehumidify and dry. Further, a gas that does not adversely affect the material can be used as the carrier gas in accordance with the type of the granular material.

After the dehumidification and drying, the valve 28
Then, the outside air is introduced, the pressure inside the drying hopper 1 is returned to the same pressure as the outside, and then, according to a request from the next step, the material discharge valve 24 is opened to remove the dehumidified and dried powder material. The powder is discharged, the switching valve 34 is switched to the resin molding machine side, the transport switching valve 31 is switched, and the transport blower 30 transports the granular material to the resin molding machine in the next step. In addition, if necessary, the particulate material to be dehumidified and dried is supplied from the collector 22 to the drying hopper 1.

When the inside of the drying hopper 1 is returned to the atmospheric pressure at the time of discharging and charging the granular material, if the inside of the drying hopper 1 is kept under vacuum, a pressure difference from the outside causes the material discharging valve 24 to return. When opening the hopper 1
This is because they flow into the inside and destroy the layered state of the granular material inside. Therefore, when the material input valve 23 and the material discharge valve 24 are maintained at the same pressure by maintaining the collector 22 in a vacuum or the like, the pressure is returned to the atmospheric pressure when the powder material is discharged. No steps are required.

Next, the heat conduction heating means used in the present invention will be described. FIG. 3 shows a drying hopper of the dehumidifying and drying apparatus of the embodiment of the present invention provided with the heat conduction heating means,
(A) is a plan view thereof, and (b) is a longitudinal sectional view thereof. As shown in FIGS. 3A and 3B, the drying hopper 1 is provided with a cylindrical heat conducting wall 2 formed of a material having good heat conductivity such as an aluminum material on the outer peripheral portion of the drying hopper 1. ,
An external heating means 3 composed of a band heater is provided on the outer periphery thereof, and a heat conductive cylinder 4 formed of a material having good thermal conductivity such as an aluminum material is provided inside the drying hopper 1, and a pipe heater is provided at a central portion thereof. The internal heating means 5 is formed. The shape of the heat conducting wall 2 of the heating hopper 1 is desirably cylindrical, but may be elliptical or square.

A plurality of vertically extending partition walls 6 are radially extended from the heat conduction wall 2 toward the center of the interior with substantially the same thickness and at substantially the same intervals. Has a plurality of vertically extending partition walls 7 extending radially from the center toward the heat conduction wall 2 forming the inner wall at substantially the same thickness and at substantially the same interval. , 7 may be provided with an appropriate interval such that the granular material does not stop, or may be in contact with each other.

In this way, a small section divided by the heat conducting wall 2, the heat conducting cylinder 4, and the partition walls 6 and 7 is generated. The heat is transmitted uniformly to the granular material inside the small compartment. In addition, as much as possible, the partition walls 6 and 7 are provided to increase the surface area for heat conduction and improve the heat conduction efficiency. Further, the partition walls 6 and 7 have a predetermined thickness in consideration of the thermal conductivity of the material so that the heat applied to the heat conductive wall 2 and the like is transmitted to the ends of the partition walls 6 and 7 without unevenness in temperature. Have.

As described above, it is desirable that the partition wall of the drying hopper be extended radially from the outside to the inside and radially from the inside to the outside. Any extending mode may be used as long as it is a partition wall that conducts heat to the powder material in a uniform manner as much as possible without unevenness in temperature. In addition, the partition wall 6,
7 do not necessarily have to be extended at substantially the same interval with substantially the same thickness, and the sectional area of the small section is not necessarily
They need not be approximately equal.

Here, when the thermal conductivity of the material constituting the drying hopper 1 is compared, the case where the temperature is 20 degrees Celsius is 37 Kcal / carbon steel conventionally used for the drying hopper.
mhr ° C, about 20 Kcal / mhr ° C or less for stainless steel, whereas aluminum recommended in the present application is:
There is a remarkable difference with 175 Kcal / mhr ° C. For pure copper, 360
Excellent in terms of Kcal / mhr ° C and thermal conductivity, but in terms of material unit price, direct contact with granular material may adversely affect the material, so appropriate coating treatment is necessary, etc. To adopt this, there are many problems to be solved.

The heat conduction heating means is constituted by the heat conduction wall 2, the external heating means (heat source) 3, the heat conduction cylinder 4, the internal heating means (heat source) 5, and the partition walls 6 and 7. Make up. The upper end of each of the partition walls 6 extending from the heat conductive wall 2 toward the inner central side forms an upper diagonal notch 61 that is inclined downward with the inner central side as a valley. Has a lower diagonal notch 62 inclined downward with the center side being a valley.

The upper end of the partition wall 7 of the heat transfer tube 4 has a central portion as the top and a downwardly projecting end 7.
1 and a lower oblique notch 7 whose lower end is inclined downward toward the periphery with the center of the hopper at the top.
2 are formed. The heat conducting wall 2 is cylindrical and constitutes the main body of the drying hopper 1. The hopper upper lid 8 is provided on the heat conducting wall 2, and the hopper is inclined downward so as to squeeze downward toward the center. A hopper lower taper portion 9 is provided and is fixedly mounted with mounting bolts (not shown).
The heat conduction cylinder 4 is supported and fixed in a suspended state at a central portion of a pipe 10 spanned between inner walls of a lower reinforcing frame 81 of the hopper upper lid portion 8.

An umbrella portion 12 is attached and fixed to the lower portion of the inner side heating means 5 composed of a pipe heater.
Further, the hopper lower tapered portion 9 has a hollow portion 91 on the inner peripheral portion.
The hollow portion 91 may be further provided with a band heater or the like as a heating means.

Further, the lower part of the partition wall 7 on the central part side is supported by the lower part of the partition wall 6 on the outer peripheral side via a ring 13, and the ring 13 is formed of a material on its upper end surface. If the upper end surface is chamfered, the particulate material does not stay. According to the drying hopper provided with such heat conduction heating means,
The granular material supplied into the drying hopper 1 is separated by an external heating means 3 provided on the outer periphery of the heat conduction wall 2 and an internal heating means 5 provided at the center of the inner heat conduction cylinder 4. Due to the heat conduction of the heated heat conduction wall 2, the heat conduction cylinder 4, and each of the partition walls 6, 7, indirectly gentle and without temperature unevenness.
It is heated and dehumidified and dried uniformly. Further, the granular material in the small section partitioned by the heat conduction wall 2, the heat conduction cylinder 4, and each of the partition walls 6 and 7 has an efficiency due to conduction heat from a surface such as the heat conduction wall 2 surrounding it. Heated.

Further, the upper end of the outer partition wall 6 is formed in the upper oblique notch 61, and the inner partition wall 7 is formed in the protruding end 71. The material does not stagnate on the upper end surface of the partition wall, and the granular material can be easily and uniformly dispersed and filled in the partition walls 6 and 7. The lower end of each of the partition walls 6 and 7 has a lower oblique notch 6.
2, 72, so that the first-in first-out umbrella part 1
2 is convenient, the heat conduction area is widened, and the heat conduction efficiency is improved.

The lower oblique notches 62 and 72 are
The shape can be determined according to the shape of the lower part of the hopper to which the partition wall is close, the shape of the first-in first-out umbrella body, and the like. The idea is to increase the heat conduction area as much as possible while following the shape of the mating member. Therefore, depending on the degree of demand for the heat conduction area, it is not always necessary to provide a notch along the shape of the mating member.

The upper oblique notch 61 and the protruding end 7
Numeral 1 is for preventing stagnation of the granular material, and it is not always necessary to provide such an upper oblique notch 61 or the like as long as it exhibits the same function. For example, the upper end surfaces of the partition walls 6 and 7 may be horizontal and chamfered so that the granular material does not stay, or R chamfered may be provided.

Further, conventionally used heating means such as a heat pipe made of copper or the like may have an adverse effect on the powdery material to be heated. However, the drying hopper 1 of the present invention is constructed and directly The heat conduction wall 2, the heat conduction cylinder 4, and the partition walls 6, 7 that are in contact with the granular material are made of an aluminum material or the like.
This is not the case because it is formed of a material that does not adversely affect the granular material during heating.

The drying hopper 1 is preferably formed of an aluminum material, and the surface thereof is preferably subjected to a surface hardening treatment such as alumite. In addition, there is an advantage that the material has less adverse effect and that it has excellent durability and long life. In addition, the heating means 3 and 5 may be provided with a nichrome heater or a ceramic heater on the heat conduction wall 2 and the heat conduction cylinder 4, or they may be partially provided and partially heated.

Further, when an aluminum material or the like is used for the drying hopper 1, it is preferable to use an extrusion-type material or a drawing-type material in which the shapes of the heat conducting walls and the partition walls are simultaneously formed. By doing so, the surface condition is finished to be smooth, the particulate material does not adhere to the surface, and the particulate material smoothly moves from the upper portion to the lower portion of the drying hopper.

FIGS. 4A and 4B are conceptual diagrams for explaining the carrier gas replacement mode of the present invention. FIG.
(B) shows the case of atmospheric pressure or positive pressure. FIG.
The apparatus for dehumidifying and drying a granular material shown in (a) has the same mode as that described with reference to FIGS. 1 and 2, and performs carrier gas replacement while performing decompression treatment.

An inlet 35 with a filter is provided at the bottom of the drying hopper 1 via a pipe, and a vacuum pump 36 is provided above the hopper 1 via a pipe. According to this, while the outside air as the carrier gas is gradually introduced from the inlet 35 with the filter, the inside of the hopper 1 is evacuated or reduced in pressure by the vacuum pump 36, whereby the carrier gas is replaced.

In this case, if the dehumidified and dried granular material is not required to be heated, the heating means may not be provided. An apparatus for dehumidifying and drying a granular material shown in FIG. 4 (b) has a configuration in which a drying hopper is not provided with a depressurizing means but only a heating means, and performs carrier gas replacement under atmospheric pressure or positive pressure. It is.

At the bottom of the drying hopper 1, an inlet 37 comprising a blower and an on-off valve is provided. Above the drying hopper 1, a gas discharging means 38 with a filter is provided via a pipe, and a heating means 39 is provided. The structure is provided. This dehumidifying and drying apparatus performs dehumidifying and drying while heating at atmospheric pressure, and according to this, the inside of the drying hopper 1 is at atmospheric pressure or by supercharging pressurized air with a blower to increase the positive pressure. In this state, the gas in the drying hopper 1 is released by the gas releasing means 38 by the amount of the supplied air to replace the carrier gas.

Note that the above filter is not essential and may not be provided. Further, it is desirable from the viewpoint of the flow of carrier gas replacement that the outside air intake port 35 with filter and the air supply receiving port 37 be provided at the bottom of the drying hopper 1 and the vacuum pump 36 and the release valve 38 be provided above the hopper 1. However, it is not necessarily limited to this. FIG.
FIG. 1 is a system diagram showing the overall configuration of another example of a dehumidifying and drying apparatus for a granular material using carrier gas replacement according to the present invention.

The dehumidifying and drying apparatus B is of an on-machine type,
In the next step, for example, it is used by directly mounting it on a material hopper of a resin molding machine. In addition, about the same part as the dehumidifying drying apparatus of FIG.
A duplicate description is omitted. The dehumidifying and drying apparatus B collects the particulate material from a nozzle 21 of a material tank to a hopper 22A of a collector provided with a suction means, passes through a material input valve 23, and enters the particulate material into the drying hopper 1. Is supplied.

The granular material dehumidified and dried using the carrier gas replacement in the drying hopper 1 is directly supplied to an injection molding machine from a material discharge valve 24 arranged at a lower portion. . In the drying hopper 1, a level gauge 14 for detecting the volume of the granular material in the drying hopper 1 is provided, and a vacuum pump 27 for evacuating the drying hopper 1 is provided at an upper part. The pressure sensor 25, the valve 28, and the pressure gauge 28a are connected to the piping.

Further, an inlet 29 for introducing outside air for replacing carrier gas is connected to the lower side. As described above, the dehumidifying and drying apparatus for a granular material using the carrier gas replacement of the present invention can be configured as an on-machine type.

[0060]

According to the first aspect of the present invention, the method for dehumidifying and drying a particulate material using carrier gas replacement is several times the real air amount excluding the volume of the particulate material stored in the drying hopper. With the carrier gas amount of about, it is possible to dehumidify and dry the powder,
Compared to a ventilated dehumidifying and drying apparatus that requires hot air about several tens of times the real air amount, the amount of gas required for dehumidifying and drying can be greatly reduced, and the apparatus can be downsized. In addition, dehumidification and drying can be efficiently performed in a short time.

According to the method for dehumidifying and drying a particulate material using carrier gas replacement according to the second aspect, in addition to the effect of the method for dehumidifying and drying a particulate material using carrier gas replacement according to the first aspect, The use of heat conduction and heat means eliminates the need to provide complicated heating means inside the drying hopper, and the hopper internal structure has a simple structure consisting only of vertically extending partition walls. Since it is used, gentle and uniform heating can be achieved. Furthermore, by providing as many partition walls as possible, the heat transfer area for transferring the conductive heat to the granular material is increased, thereby improving the heat transfer efficiency.

According to a third aspect of the present invention, there is provided a dehumidifying / drying apparatus for a granular material using carrier gas replacement, wherein only the means for heating a granular material is provided. This is an apparatus for realizing a dehumidifying and drying method in which heating performed under atmospheric pressure or positive pressure and carrier gas replacement are combined, and the effect of the method of claim 1 can be exhibited.

According to a fourth aspect of the present invention, there is provided an apparatus for dehumidifying and drying a powdery or granular material using carrier gas replacement, comprising only a depressurizing means of a drying hopper. This is an apparatus for realizing a dehumidifying and drying method in which the method of the present invention is combined with the replacement of a carrier gas. According to the apparatus for dehumidifying and drying a granular material using the carrier gas replacement according to claim 5,
2. An apparatus which comprises both a heating means for a granular material and a decompression means for a drying hopper, and realizes a dehumidification and drying method in which heating and decompression treatment and carrier gas replacement are combined among the dehumidification and drying methods according to claim 1. Thus, the effect of the method of claim 1 can be more efficiently exhibited.

According to the apparatus for dehumidifying and drying a particulate material using the carrier gas replacement according to the sixth aspect, the dehumidification of the particulate material using the carrier gas replacement according to any one of the third or fifth aspects. In addition to the effect of the drying device, since the heating means is a heat conduction heating means, the internal structure of the hopper becomes a simple structure consisting only of vertically extending partition walls, and because the heat conductivity of the material is utilized, The effect of the heat conduction heating means that gentle and uniform heating can be performed and the heat efficiency is good, and the effect of the carrier gas replacement are synergistically exhibited.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an entire configuration of an example of a dehumidifying and drying apparatus for a granular material using carrier gas replacement according to the present invention.

FIGS. 2A and 2B show an external appearance of a main body of a dehumidifying and drying apparatus for a granular material according to an embodiment of the present invention, wherein FIG. 2A is a front view partially cut away, and FIG.

FIGS. 3A and 3B show a drying hopper of a dehumidifying and drying apparatus for a granular material according to an embodiment of the present invention, wherein FIG. 3A is a plan view and FIG.

4A and 4B are conceptual diagrams illustrating an embodiment of carrier gas replacement according to the present invention, wherein FIG. 4A is a diagram in a vacuum state, and FIG. 4B is a diagram in an atmospheric pressure or a positive pressure.

FIG. 5 is a system diagram showing the overall configuration of another example of a dehumidifying and drying apparatus for a granular material using carrier gas replacement according to the present invention.

FIG. 6 is a longitudinal sectional view showing an example of a conventional apparatus for dehumidifying and drying a granular material.

[Explanation of symbols]

 A dehumidifying and drying apparatus 1 drying hopper 29, 35 inlet 27, 36, 38 gas releasing means 27 depressurizing means 2 to 7 heat conduction heating means (heating means) 39 heating means

Continued on the front page (72) Inventor Koichi Katsumura 1-10-4 Nagao Furniture-cho, Hirakata-shi, Osaka Inside Matsui Seisakusho R & D Center (72) Inventor Masaaki Nosaka 1-10 Nagao-Furniture-cho, Hirakata-shi, Osaka No. 4 Matsui Manufacturing Co., Ltd. Technology Development Center (72) Inventor Osamu Matsui 6-5-26 Tanimachi, Chuo-ku, Osaka City, Osaka Prefecture F-term in Matsui Manufacturing Co., Ltd. 4F201 AC01 AL06 AL07 AL20 BA04 BC01 BC02 BC12 BC15 BC19 BN01 BN23 BN36 BN37 BN39 BQ02 BQ08

Claims (6)

[Claims] Claims: 1. After storing a granular material in a drying hopper,
By heating or depressurizing the stored granular material in a state where the drying hopper is sealed, humidity and temperature are stored in the drying hopper while generating various gases such as steam and volatile gas. By using a carrier gas replacement characterized by introducing a carrier gas prepared as described above from the outside and deriving the gas containing the miscellaneous gas to the outside of the drying hopper, the particulate material is dehumidified and dried. A method for dehumidifying and drying a powder material. 2. The gas containing the miscellaneous gas according to claim 1, wherein the carrier gas is introduced from the outside while heating the granular material by the heat conduction heating means provided in the drying hopper. A method for dehumidifying and drying a particulate material using carrier gas replacement, wherein the method is led to the outside of the device. 3. A drying hopper for storing and drying the powder material, a heating means for heating the powder material stored in the drying hopper, and a humidity and temperature controlled from the outside by the drying hopper. A gas inlet means for introducing the carrier gas, and gas discharging means for leading out a gas containing miscellaneous gases such as water vapor and volatile gas generated in the drying hopper, and the drying hopper is sealed. By heating the stored powder material, generating various gases such as water vapor and volatile gas, the carrier gas prepared such as humidity and temperature is introduced into the drying hopper from the outside. Dehumidifying and drying the particulate material using carrier gas replacement, wherein the particulate material is dehumidified and dried by introducing the gas containing the miscellaneous gas to the outside of the drying hopper. . 4. A drying hopper for storing and drying the granular material, a decompression means for reducing the pressure in the drying hopper, and introducing a carrier gas, such as humidity and temperature, from outside into the drying hopper. Having a mouth and gas discharging means for discharging gas including miscellaneous gas such as water vapor and volatile gas generated in the drying hopper to the outside, and storing the powder particles in a state where the drying hopper is sealed. By generating a miscellaneous gas such as water vapor or a volatile gas by subjecting the body material to a reduced pressure treatment, a carrier gas prepared such as humidity and temperature is introduced from the outside into the drying hopper to contain the miscellaneous gas. An apparatus for dehumidifying and drying a particulate material using carrier gas replacement, wherein the particulate material is dehumidified and dried by introducing a gas to the outside of a drying hopper. 5. A drying hopper for storing and drying the powder material, a heating means for heating the powder material stored in the drying hopper, a pressure reducing means for reducing the pressure in the drying hopper, The drying hopper has an inlet for introducing a carrier gas whose humidity and temperature are adjusted from the outside, and gas discharging means for discharging a gas containing miscellaneous gases such as water vapor and volatile gas generated in the drying hopper to the outside. By heating and depressurizing the stored particulate material in a state where the drying hopper is sealed, while generating various gases such as water vapor and volatile gas, the humidity and temperature inside the drying hopper are reduced. By introducing the prepared carrier gas from the outside from the outside and drawing out the gas containing the miscellaneous gas to the outside of the drying hopper, the particulate material is dehumidified and dried. Dehumidifying and drying apparatus for powdered or granular material with a carrier gas displacement to be. 6. An apparatus for dehumidifying and drying a granular material using carrier gas replacement according to claim 3, wherein the heating means of the drying hopper is a heat conduction heating means.