JP2015100275A - Heat treatment apparatus and heat treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment device and a heat treatment method in which powder granules can be loaded into a condensable gas without interposing a mechanical device for backflow prevention, and the heating efficiency is excellent.SOLUTION: A heat treatment device 1 includes: supply means 6 for supplying powder granules 10; a powder granule loading unit 7 with the powder granules 10 loaded from the supply means 6; non-condensable gas supply units 20, 23 for blowing a non-condensable gas to the supply means 6 or the powder granule loading unit 7; a condensable gas supply unit 26 for blowing a condensable gas in the mixture of the powder granules 10 and the non-condensable gas; and a heating unit 8 where the powder granules 10 are heated by the condensable gas. The powder granule loading unit 7 is disposed so that the powder granules 10 mixed with the non-condensable gas are made to flow from top to bottom toward the heating unit 8, and the powder granules 10 are loaded in an air flow of the condensable gas pressurized in the heating unit 8 and are heat-treated.

Description

  The present invention relates to a heat treatment apparatus and a heat treatment method for heating and sterilizing or denaturing a granular material using a condensable gas, and more particularly to a structure and method for charging a granular material into a heating unit.

  2. Description of the Related Art Conventionally, a heat treatment apparatus is known in which a granular material is introduced into a pressurized condensable gas stream and heated to sterilize (see, for example, Patent Documents 1 to 4 below). In such a heat treatment apparatus, since there is a pressure difference between the supply source of the granular material and the heating unit that heats the granular material, it is necessary to prevent the condensable gas from being blown up. That is, when the condensable gas blows up, in addition to hindering the charging of the granular material to the heating unit, it also causes the granular material to be moistened.

  In the heat treatment apparatuses disclosed in Patent Document 1 and Patent Document 3, powder particles sucked by an ejector using superheated steam as a drive source are put into a condensable gas. In this configuration, since the granular material is sucked by the ejector, no blow-up occurs.

  In the heat treatment apparatus of Patent Document 2, the granular material from the hopper is dropped downward through a charging apparatus, and the granular material is charged into a superheated steam stream. In this configuration, if, for example, a highly airtight rotary valve is used as the input device, the powder particles are input into the superheated steam stream through the rotary valve, so that no blowing occurs.

  In the heat treatment apparatus of Patent Literature 4, after supplying the granular material to the pressurized non-condensable gas, the non-condensable gas transports the granular material in the lateral direction to make the granular material non-condensable. It is injected into a stream of gas and water vapor mixed with heat and pressure. In this configuration, the granular material is introduced into the air flow of the heated and pressurized mixed gas together with the pressurized non-condensable gas, so that the blow-up is prevented.

Japanese Patent No. 4499184 Japanese Patent Publication No. 63-50984 JP 2000-157615 A JP 2000-24091 A

  In each structure of the said patent documents 1-4, although the blow-up of a granular material can be prevented, there existed the following problems. The ejectors used in the heat treatment apparatuses of Patent Documents 1 and 3 exhibit a suction effect due to a pressure difference, and have a low degree of freedom in pressure setting and arrangement, so the shape of the apparatus and the conditions of heat treatment are limited. It will be. Further, in the configuration using the ejector, the processing amount is reduced.

  In a configuration in which a charging device is used like the heat treatment device of Patent Document 2, condensation occurs due to a temperature difference when a condensable gas touches the charging device. For example, when a rotary valve is used as a charging device, after the rotor is warmed by the condensable gas, the granular material enters the rotor mass, the rotor cools and condensation occurs, and the condensable gas touches the cooled rotor again. Condensation occurs due to temperature difference. Due to dew condensation, the granular material becomes a lump that adheres to the rotor, which is mixed into the granular material, or due to the adhesion, the capacity of the rotor mass decreases, and the amount of processing decreases. Even if a heater for heating the rotor is used, dew condensation occurs in a configuration in which the granular material and the condensable gas are in contact with each other. In addition, depending on the type of powder and other particles, the rotor may corrode due to long-time adhesion or volatilized components. Furthermore, cleaning is difficult.

  The heat treatment apparatus of Patent Document 4 needs to transport the granular material in order to introduce the granular material into the air stream of the heated and pressurized mixed gas. For this reason, in order to transport the granular material in the lateral direction as shown in FIG. 1 of Patent Document 4, it is necessary to apply a force to push the granular material in the lateral direction when setting the amount of non-condensable gas used. The amount of non-condensable gas used is increased. Since the non-condensable gas is introduced into the gas stream of the non-condensable gas and water vapor, the ratio of the non-condensable gas in the heat-pressure mixed gas during heating increases, and the heating efficiency decreases. End up. In addition, since the granular material and non-condensable gas are introduced from the lateral direction into the air flow of the heated and pressurized mixed gas of non-condensable gas and water vapor, the granular material collides with the side of the tube and the air flow is disturbed, making it easy to blow up. turn into.

  The present invention is for solving the above-described conventional problems, and can be used to introduce a granular material into a flow of condensable gas without interposing a backflow prevention mechanical device, and It is an object of the present invention to provide a heat treatment apparatus and a heat treatment method with good heating efficiency.

  In order to achieve the above object, the heat treatment apparatus of the present invention is a heat treatment apparatus that heats a powder by introducing the powder into a condensable gas stream, and a supply means for supplying the powder A granular material charging unit into which the granular material is charged from the supply unit; a non-condensable gas supply unit that blows a non-condensable gas into the supplying unit or the granular material charging unit; and the granular material. A condensable gas supply unit that blows condensable gas into the non-condensable gas mixture; and a heating unit that heats the powder particles by the condensable gas. The granular material mixed with the natural gas is arranged to flow downward from above toward the heating unit, and the granular material is in the air flow of the condensable gas pressurized by the heating unit. And heat-treated.

  The heat treatment method of the present invention is a heat treatment method in which a granular material is put into a condensable gas stream and heat-treated, the supply means supplying the granular material, and the granular material from the supply means A granular material charging unit into which the body is charged and a heating unit in which the granular material is heated by the condensable gas, and a non-condensable gas is blown into the supply means or the granular material charging unit, A granule charging part is arranged so that the powder mixed with the non-condensable gas flows downward from above toward the heating part, and the powder is added by the heating part. The heat treatment is performed by introducing the gas into the compressed condensable gas stream.

  According to the heat treatment apparatus and the heat treatment method of the present invention, since the supply means or the granular material charging unit is injected with non-condensable gas, the granular material is heated while preventing the condensable gas from being blown up. Can be put in. As a result, the mechanical device for preventing backflow is not essential, the structure of the device can be simplified, the enlargement of the device can be prevented, the durability is increased, and the cleaning property is also improved. Further, this configuration is suitable for feeding the granular material to the heated heating section. For example, if a valve is provided on the upstream side and downstream side of the supply means, a non-condensable gas is supplied in a state where the upstream valve and the downstream valve are closed, and the inside of the supply means is powdered. After pressurizing to a pressure equivalent to that of the charging unit, the valve on the downstream side is opened to put the supply means in a semi-sealed state, so that it is more advantageous to charge the granular material to the heated heating unit.

  Moreover, since the granular material injection | throwing-in part is arrange | positioned so that the granular material mixed with the non-condensable gas may flow downward from the upper direction toward a heating part, a granular material is sent by gravity. That is, in this invention, since the usage-amount of noncondensable gas can be suppressed and the ratio of the noncondensable gas in a heating part can be suppressed, the fall of heating efficiency can be prevented. Furthermore, when the granular material is introduced into the air flow of the condensable gas, it flows in a certain direction from the top to the bottom, so that the air flow is not disturbed and the blowing up of the condensable gas is suppressed, so The effect of preventing blow-up is further increased.

  In the heat treatment method of the present invention, the ratio of the condensable gas in the total mass flow rate of the non-condensable gas and the condensable gas is not particularly limited, but is preferably in the range of 65.00 to 99.97%. . According to this numerical range, it is possible to minimize a decrease in heating efficiency, and it is advantageous for preventing the condensable gas from being blown up, and also advantageous for continuous heat treatment. That is, when the ratio of the condensable gas is set to 65.00% or more, it is advantageous for ensuring the heating efficiency. On the other hand, by setting the ratio of condensable gas to 99.97% or less, the ratio of non-condensable gas is ensured, which is advantageous for preventing the condensable gas from being blown up, and the powder is solidified by moisture. This is advantageous for continuous heat treatment. Even if the ratio of the non-condensable gas is 0.03%, the non-condensable gas flows together with the air originally remaining in the powder supply means or the powder input portion, Blowing up is prevented, and the granular material is also prevented from being moistened. Moreover, what mixed noncondensable gas and condensable gas turns into condensable gas. Specifically, at the interface between the non-condensable gas and the condensable gas, the non-condensable gas slowly mixes with the condensable gas and becomes a condensable gas. If the supply amount of non-condensable gas is 0.03% or more, the position of the boundary surface can be maintained. However, if it is less than that, the amount of the non-condensable gas mixed is larger, the boundary surface gradually rises, and the supplying means condenses.

  According to the present invention, since the supply means or the granular material charging unit is injected with the non-condensable gas, the granular material can be charged into the heating unit while preventing the condensable gas from being blown up. As a result, the mechanical device for preventing backflow is not essential, the structure of the device can be simplified, the enlargement of the device can be prevented, the durability is increased, and the cleaning property is also improved.

  Moreover, since the granular material injection | throwing-in part is arrange | positioned so that the granular material mixed with the non-condensable gas may flow downward from the upper direction toward a heating part, a granular material is sent by gravity. That is, in this invention, since the usage-amount of noncondensable gas can be suppressed and the ratio of the noncondensable gas in a heating part can be suppressed, the fall of heating efficiency can be prevented. Furthermore, when the granular material is introduced into the air flow of the condensable gas, it flows in a certain direction from the top to the bottom, so that the air flow is not disturbed and the blowing up of the condensable gas is suppressed, so The effect of preventing blow-up is further increased.

The schematic block diagram of the heat processing apparatus which concerns on one Embodiment of this invention. The schematic diagram which shows the 2nd example of the heat processing apparatus which concerns on one Embodiment of this invention. The schematic diagram which shows the 3rd example of the heat processing apparatus which concerns on one Embodiment of this invention. The schematic diagram which shows the 4th example of the heat processing apparatus which concerns on one Embodiment of this invention. The schematic block diagram which shows the structure which provided the stirring part and the deceleration part in the heating part of the heat processing apparatus which concerns on one Embodiment of this invention. The schematic block diagram which shows another structure which provided the stirring part and the deceleration part in the heating part of the heat processing apparatus which concerns on one Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a heat treatment apparatus 1 according to an embodiment of the present invention. The heat treatment apparatus 1 is an apparatus for heat-treating and sterilizing or denaturing the granular material 10. The kind of the granular material 10 which is the object of the heat treatment is not particularly limited. For example, grain powder such as wheat flour, rice flour, seaweed powder, fish powder, vegetable powder, vegetable chip powder, tea leaf powder, spice powder such as pepper, Examples include various additive powders, pharmaceutical powders, cosmetic powders, and various feed powders.

  In the heat treatment apparatus 1 shown in FIG. 1, a dropping cylinder 2, a hopper 3, a supply means 6 for a granular material 10, a granular material charging unit 7, and a heating unit 8 are arranged in this order from the upstream side. When the granular material 10 is dropped toward the dropping cylinder 2 (arrow a), the granular material 10 is filled into the hopper 3 that is a storage part. A non-condensable gas supply unit 20 is connected to the supply means 6. The non-condensable gas supply unit 20 includes a non-condensable gas supply pipe 21 and a non-condensable gas supply source 22.

  The dropping cylinder 2 is an example of a configuration for receiving the powder body 10 in the heat treatment apparatus 1 and may have another configuration. An upper valve 4 is disposed upstream of the supply means 6, and a lower valve 5 is disposed downstream of the supply means 6. Both the upper valve 4 and the lower valve 5 have a mechanism for opening and closing the flow path of the granular material 10. According to this configuration, the upper valve 4 is closed and the lower valve 5 is opened, so that the flow path of the granular material 10 can be in a semi-sealed state. When dropping the granular material 10 from the hopper 3 onto the supply means 6, the upper valve 4 is opened and the lower valve 5 is closed.

  When the dropping of the granular material 10 to the supply means 6 is completed, the non-condensable gas is supplied from the non-condensable gas supply section 20 with the upper valve 4 closed, that is, with the upper valve 4 and the lower valve 5 closed. 6 and the inside of the supply means 6 is pressurized to a pressure equivalent to that of the granular material charging unit 7. In this state, the lower valve 5 is opened, and the granular material 10 in the supply means 6 is supplied to the granular material charging unit 7 together with the non-condensable gas from the non-condensable gas supply unit 20. The non-condensable gas is, for example, air, oxygen, nitrogen, carbon dioxide, and may be a mixed gas containing these components.

  The supply means 6 should just be what can supply the granular material 10 toward the next process, for example, can use a screw feeder, a table feeder, a rotary feeder, and may use a hopper. The screw feeder is a mechanism for rotating the spiral screw to discharge the powder particles 10. A table feeder is a mechanism which discharges the granular material 10 on a table by rotation of a table. The hopper is a mechanism for discharging by providing rotating blades. In the case of a granular material having high fluidity, the fixed amount may be discharged only by adjusting the opening degree of the discharge port without providing the rotating blade. In any mechanism, the supply amount of the granular material 10 can be adjusted by adjusting the rotational speed of the screw or table and the opening degree of the discharge port. A plurality of supply means 6 may be combined. Even in this configuration, if at least one of the supply means 6 is provided with a non-condensable gas supply unit 20 and a depressurization mechanism including a valve or the like, and an upper valve 4 and a lower valve 5 are provided. A semi-sealed state can be realized, and the granular material 10 can be supplied under pressure.

  Further, as the supply means 6, an airtight supply means such as a rotary valve may be used. In this case, the non-condensable gas supply unit 20, the depressurization mechanism, the upper valve 4 and the lower valve 5 provided in the supply means 6 can be omitted. Furthermore, the supply unit 6 may combine a plurality of supply units such as a combination of a table feeder and a rotary valve. As will be described later, the heat treatment apparatus 1 according to this embodiment is configured to be able to perform heat treatment without using a rotary valve, but the rotary valve is connected to the supply means 6, the non-condensable gas supply unit 20, Since the function equivalent to the configuration in which the depressurization mechanism, the upper valve 4 and the lower valve 5 are provided is exhibited, as will be described later, if the non-condensable gas supply unit 23 is provided in the granular material charging unit 7, the rotary A valve can also be used. In the heat treatment apparatus 1 according to the present embodiment, since the condensable gas is prevented from being blown up by the non-condensable gas, the condensable gas does not touch the rotor even if the rotary valve is used. Therefore, condensation does not occur in the rotor, and adhesion of the granular material 10 to the rotor can be prevented.

  When supplementing the supply means 6 with the granular material 10, the lower valve 5 is closed, the supply means 6 is depressurized by the depressurization mechanism, the upper valve 4 is opened, and a new granular material 10 from the hopper 3 is opened. .

  The granular material charging unit 7 is a part for charging the granular material 10 supplied from the supply means 6 to the heating unit 8. A non-condensable gas supply unit 23 is connected to the granular material charging unit 7. The non-condensable gas supply unit 23 includes a non-condensable gas supply pipe 24 and a non-condensable gas supply source 25. The non-condensable gas from the non-condensable gas supply unit 23 is supplied to the granular material charging unit 7. The granular material 10 is mixed with this non-condensable gas. The kind of non-condensable gas is the same as the non-condensable gas supplied from the non-condensable gas supply unit 20.

  In FIG. 1, the granular material charging unit 7 is arranged in the vertical direction, but is not limited thereto, and may be arranged so that the granular material 10 can flow downward from above. The cross-sectional shape is not limited to a circle. Furthermore, it is not restricted to what was comprised alone, and there may be seams, such as a flange and a ferrule.

  A condensable gas supply unit 26 is connected to the downstream side of the non-condensable gas supply unit 23. The condensable gas supply unit 26 includes a condensable gas supply pipe 27 and a condensable gas supply source 28. The condensable gas is, for example, water vapor or various solvent vapors, and the water vapor may be either saturated water vapor or superheated water vapor.

  The condensable gas from the condensable gas supply unit 26 is blown into the heating unit 8. The heating unit 8 is a part where the granular material 10 is heated by the condensable gas. A pressurized condensable gas stream is formed in the heating unit 8. The granular material 10 is thrown into the air stream together with the non-condensable gas from the non-condensable gas supply unit 20 and the non-condensable gas supply unit 23.

  In the heating part 8, the granular material 10 is heat-processed with a condensable gas. That is, due to the temperature difference between the granular material 10 and the condensable gas, the surface of the granular material 10 is condensed, and the granular material 10 is heated. When the granular material 10 is supplied into the cyclone 11, the condensable gas and the granular material 10 are separated in the cyclone 11. The condensable gas is exhausted through the exhaust path 12, and the powder 10 separated from the condensable gas is recovered through the recovery path 13.

  Since the non-condensable gas flows together with the condensable gas in the heating unit 8, the heating mode of the granular material 10 varies depending on the temperature of the non-condensable gas. In the case of a raw material in which condensation of the condensable gas does not become a problem (for example, a powdered granule such as defatted soybean), the temperature of the non-condensable gas may be normal temperature. In the case of a raw material to be heated while suppressing condensation of the condensable gas (for example, a granular material that becomes sticky due to water absorption), the non-condensable gas may be heated in advance.

  In FIG. 1, the heating unit 8 includes a cyclone 11 in addition to the tubular portion. However, the cyclone 11 may not be used as the heating unit 8 but may be dedicated to the separation of the condensable gas and the granular material 10. In this case, it is good also as a cooling part by which the cooling wind from a fan is ventilated to the tubular part between the heating part 8 and the cyclone 11. FIG. The same applies to FIGS. 2 to 4 described later.

  In FIG. 1, the tubular portion of the heating unit 8 includes a portion arranged in the vertical direction (vertical direction). However, the present invention is not limited to this, and the heating unit as illustrated in FIGS. 3 and 4 described later. Eight tubular portions may be arranged in the horizontal direction (horizontal direction). Moreover, the cross-sectional shape of the heating unit 8 is not limited to a circular shape. Furthermore, the tubular portion of the heating unit 8 is not limited to a single piece, and may have a joint such as a flange or a ferrule.

  In the present embodiment, since the supply means 6 or the granular material charging unit 7 is injected with non-condensable gas, the granular material 10 can be charged into the heating unit 8 while preventing the condensable gas from being blown up. . Thus, in the present embodiment, a mechanical device such as a rotary valve for the purpose of preventing backflow is not essential. For this reason, the structure of the apparatus can be simplified, the enlargement of the apparatus can be prevented, the durability is enhanced, and the cleaning property is also improved. Further, if the upper valve 4 and the lower valve 5 are provided as in the present embodiment, the upper valve 4 is closed and the lower valve 5 is closed when the granular material 10 is supplied to the granular material charging unit 7. It is more advantageous to supply the granular material 10 to the pressurized heating unit 8 by opening the.

  Furthermore, in this embodiment, the granular material injection | throwing-in part 7 is arrange | positioned so that the granular material 10 mixed with the non-condensable gas may flow toward the heating part 8 from upper direction to the downward direction. According to this arrangement, the granular material is sent by gravity. That is, as described above, in the present embodiment, the non-condensable gas is used to put the granular material 10 into the air flow of the condensable gas, but the amount of use can be suppressed. By this, the ratio of the noncondensable gas in the heating part 8 can be suppressed, and the fall of heating efficiency can be prevented. Furthermore, when the granular material 10 is thrown into the air flow of the condensable gas, it flows in a certain direction from the top to the bottom, so that the air flow is not disturbed and the blowing up of the condensable gas is suppressed. The effect of preventing blowing up to 6 is further increased.

  Next, the mass flow rate ratio between the non-condensable gas and the condensable gas will be described. As described above, the use of the non-condensable gas prevents the condensable gas from being blown up, but it is preferable to suppress the amount of the non-condensable gas used from the viewpoint of increasing the heating efficiency. That is, when the ratio of the non-condensable gas is increased in the heating unit 8, the non-condensable gas prevents the condensable gas from coming into contact with the granular material 10, which is disadvantageous for heating the granular material 10. On the other hand, when the ratio of the condensable gas is increased in the heating unit 8, it is disadvantageous for preventing the condensable gas from being blown up. For this reason, it is preferable that the ratio of the condensable gas in the total mass flow rate of the non-condensable gas and the condensable gas is in the range of 65.00 to 99.97%. If it is in this numerical range, while being able to suppress the fall of heating efficiency to the minimum, it becomes advantageous to the blowing-up of a condensable gas, and also becomes advantageous also to continuous heat processing. That is, by setting the ratio of the condensable gas to 65.00% or more, it is advantageous for ensuring the heating efficiency. On the other hand, by setting the ratio of the condensable gas to 99.97% or less, the ratio of the non-condensable gas is ensured, which is advantageous for preventing the condensable gas from being blown up, and the granular material 10 is solidified by moisture. It becomes advantageous for continuous heat treatment. Even if the ratio of the non-condensable gas is 0.03%, the non-condensable gas flows together with the air originally remaining in the supply means 6 of the granular material 10 or the granular material charging unit 7, so that it is condensed. It is possible to prevent the natural gas from being blown up and to prevent the granular material 10 from being moistened. Moreover, what mixed noncondensable gas and condensable gas turns into condensable gas. Specifically, at the interface between the non-condensable gas and the condensable gas, the non-condensable gas slowly mixes with the condensable gas and becomes a condensable gas. If the supply amount of non-condensable gas is 0.03% or more, the position of the boundary surface can be maintained. However, if it is less than that, the amount of the non-condensable gas mixed is larger, the boundary surface gradually rises, and the supplying means condenses.

  Hereinafter, various modifications of the present embodiment will be described. FIG. 2 is a schematic diagram illustrating a second example of the present embodiment. Although the heat treatment apparatus 1 of FIG. 2 is illustrated in a simplified manner as compared with FIG. 1, the basic configuration is the same as that of the heat treatment apparatus 1 of FIG. For this reason, the same number is attached | subjected to the thing of the same structure as FIG. 1, and the description is abbreviate | omitted. The same applies to FIGS. In the configuration of FIG. 1, there is one supply unit 6. However, in the configuration of FIG. 2, two supply units 6 are installed, and a non-condensable gas supply unit 20 ′ is connected upstream of the second supply unit 6. . The non-condensable gas supply unit 20 ′ includes a non-condensable gas supply pipe 21 ′ and a non-condensable gas supply source 22 ′. Further, the non-condensable gas supply unit 23 is not connected to the granular material charging unit 7, and a non-condensable gas is blown into the granular material charging unit 7 through the supply means 6 by the non-condensable gas supply unit 20 ′. Yes. In this embodiment, it is only necessary that the non-condensable gas can be substantially blown into the granular material charging unit 7, and there are no restrictions on the arrangement position and the number of non-condensable gas supply units.

  FIG. 3 is a schematic diagram illustrating a third example of the present embodiment. The configuration of FIGS. 1 to 2 includes a portion in which the tubular portion of the heating unit 8 is arranged in the vertical direction, but the configuration of FIG. 3 is that the tubular portion of the heating unit 8 is arranged in the lateral direction. Is different from the configuration of FIG. FIG. 4 is a schematic diagram illustrating a fourth example of the present embodiment. The configuration of this figure is different from the configuration of FIG. 2 in that the tubular portion of the heating unit 8 is arranged in the lateral direction.

  As described above, in the present embodiment, it is only necessary to be able to substantially blow non-condensable gas into the granular material charging unit 7, and in addition to this, there are no restrictions on the arrangement position or number of non-condensable gas supply units. Absent. Further, the arrangement direction of the heating unit 8 is not limited.

  Moreover, in the structure of FIGS. 1-4, although the condensable gas supply part 26 is one, the number is not limited. Furthermore, the condensable gas supply part 26 should just be arrange | positioned downstream of the non-condensable gas supply part, and there is no restriction | limiting of an arrangement position other than this.

  The heating unit 8 may have a configuration in which a stirring unit and a speed reduction unit are provided as described below. In the heating unit 8, the uniform heating effect of the powder 10 is enhanced by stirring the powder 10. Moreover, in the heating part 8, the residence time in the heating part 8 can be ensured and the length of the heating part 8 can be shortened by decelerating the flow velocity.

  5 and 6 are schematic configuration diagrams showing a configuration in which the stirring unit 14 and the speed reduction unit 15 are provided in the heating unit 8. The fluid becomes turbulent due to the increased speed and is agitated. When the granular material 10 is stirred, it can be heated uniformly, so that unevenness in the heat treatment can be prevented. In the heating unit 8 of FIG. 5, an accelerating unit 16 having a diameter narrowed toward the downstream side is provided, and a stirring unit 14 is provided on the downstream side of the accelerating unit 16. In the stirring part 14, the granular material 10 whose flow velocity increased in the acceleration part 16 flows, the granular material 10 is stirred, and a uniform heating effect increases.

  In view of stirring efficiency, the flow rate is preferably 50 m / sec or more. In the configuration of FIG. 5, even when the flow velocity near the entrance of the heating unit 8 is slow (less than 50 m / second), the flow velocity increases in the acceleration unit 16 and the flow rate in the stirring unit 14 may be 50 m / second or more. it can. On the other hand, if a flow velocity of 50 m / sec or more is secured near the entrance of the heating unit 8, a stirring effect can be obtained even if the acceleration unit 16 is not provided. Although the accelerating unit 16 is not provided in the configuration of FIG. 6, the portion denoted by reference numeral 14 substantially serves as a stirring unit. In the configuration of FIG. 5, even if a flow velocity of 50 m / sec or more is secured near the entrance of the heating unit 8, the stirring effect is further enhanced by further increasing the flow velocity in the acceleration unit 16.

  5 and 6, the speed reduction unit 15 is provided in the heating unit 8. As described above, the flow rate is preferably 50 m / second or more in terms of stirring efficiency, but when the flow rate is increased, the residence time in the heating unit 8 is shortened. For this reason, in order to ensure a heating effect, it is necessary to lengthen the heating part 8. In the configuration of FIGS. 5 and 6, a speed reduction unit 15 is provided in which the diameter of the heating unit 8 is gradually increased toward the downstream side. By providing the speed reduction part 15, the residence time can be secured, so the heating part 8 is shortened and the apparatus can be prevented from becoming large.

Hereinafter, the present embodiment will be described more specifically with reference to examples. Example 1 is the structure similar to the heat processing apparatus 1 shown in FIG. 1, and the granular material injection | throwing-in part 7 and the heating part 8 are the structure of a vertical arrangement | positioning. Example 2 has the same configuration as that of the heat treatment apparatus 1 shown in FIG. The operating conditions of Example 1 and Example 2 are the same and are as follows.
Powder body: wheat flour (number of added bacteria: 1.4 × 10 ⁴ cfu / g)
Processing volume 100kg / h
Operating time: 1 hour Non-condensable gas: Air (temperature 200 ° C., mass flow rate 13 kg / h)
Condensable gas: superheated steam (temperature 210 ° C., pressure 0.4 MPa, mass flow rate 80 kg / h)
Ratio of superheated steam in the total mass flow rate of air and superheated steam: 86%

  For both Example 1 and Example 2, the flour flow during operation was smooth. After completion of the operation, the inside of the supply means 6 and the granular material charging part 7 was confirmed, and it was confirmed that there was no adhesion of flour and superheated steam was not blown up.

In order to confirm the heating efficiency, the number of bacteria in the flour after the heat treatment was measured. When 10 points were sampled, as described above, the number of bacteria before the heat treatment was 1.4 × 10 ⁴ cfu / g, whereas for both Example 1 and Example 2, the average after the heat treatment The number of bacteria was less than 10 ² cfu / g. There was almost no variation in the number of bacteria. That is, it was confirmed that uniform heat treatment could be realized for both Example 1 and Example 2.

(Comparative example)
The operation check of Comparative Example 1 and Comparative Example 2 was also performed together with the above Examples. In each of the above Examples and Comparative Example 1, the arrangement of the granular material charging unit 7 is different. In each of the above examples, the granular material charging unit 7 has a vertical arrangement, while the comparative example 1 has a horizontal arrangement. The comparative example 2 is operated by stopping the supply of the non-condensable gas by the non-condensable gas supply unit 20 and the non-condensable gas supply unit 23 with respect to the example 1. The operating conditions of Comparative Example 1 were as follows, and the other conditions were the same as those in the previous examples.
Air (non-condensable gas) mass flow rate 68 kg / h
Superheated steam (condensable gas) mass flow rate 83kg / h
Percentage of superheated steam in the total mass flow of air and superheated steam: 55%

The evaluation method of the heating efficiency was the same as that in each of the above examples, and 10 points of the number of bacteria in the flour after the heat treatment were sampled. The number of bacteria before the heat treatment was 1.4 × 10 ⁴ cfu / g, whereas the average number of bacteria after the heat treatment was less than 2.8 × 10 ³ cfu / g. There was also a variation in the number of bacteria. Therefore, the heating efficiency of Comparative Example 1 was lower than that of the above Examples. As this cause, since the comparative example 1 made the granular material injection | throwing-in part 7 horizontal arrangement | positioning, it is mentioned that the air quantity was increased for conveyance of flour. That is, it can be considered that the heating efficiency in Comparative Example 1 was lower than that in each of the above Examples because the air ratio in the heating part increased.

The operating conditions of Comparative Example 2 were as follows, and other conditions were the same as those of Comparative Example 1.
Air (non-condensable gas) mass flow rate 0 kg / h
Superheated steam (condensable gas) mass flow rate 82kg / h
Percentage of superheated steam in the total mass flow of air and superheated steam: 100%

  In Comparative Example 2, the operation was stopped because the flour did not come out of the recovery path 13 when the heat treatment was performed for 5 minutes. When the supply means 6 was disassembled, the wheat flour became a “dama” that hardened with moisture and was clogged with the granular material charging unit 7. As a result of measuring the number of fungi of the heat-treated flour, the variation was less than 100 cfu / g. In other words, it has been found that a configuration in which the ratio of the condensable gas is 100% is effective for heat treatment, but is limited to a short time, and is not suitable for practical use because continuous operation is not possible.

DESCRIPTION OF SYMBOLS 1 Heat processing apparatus 2 Drop cylinder 3 Hopper 6 Supply means 7 Granule input part 8 Heating part 10 Powder 11 Cyclone 20, 23 Noncondensable gas supply part 26 Condensable gas supply part

Claims (2)

A heat treatment apparatus that heats a powder by putting it into a condensable gas stream,
Supply means for supplying the powder particles;
A granular material charging unit into which the granular material is charged from the supply means;
A non-condensable gas supply unit for blowing a non-condensable gas into the supply means or the granular material charging unit;
A condensable gas supply section for blowing condensable gas into the mixture of the granular material and the non-condensable gas;
A heating unit in which the powder particles are heated by the condensable gas,
The granular material charging unit is arranged such that the granular material mixed with the non-condensable gas flows downward from above toward the heating unit,
The said granular material is thrown into the air flow of the said condensable gas pressurized by the said heating part, and is heat-processed, The heat processing apparatus characterized by the above-mentioned. It is a heat treatment method in which powder is injected into a condensable gas stream and heat-treated,
Supply means for supplying the powder particles;
A granular material charging unit into which the granular material is charged from the supply means;
A heating unit that heats the granular material by a condensable gas,
Blowing a non-condensable gas into the supply means or the granular material charging part,
The granular material charging unit is arranged so that the granular material mixed with the non-condensable gas flows downward from above toward the heating unit,
The heat treatment method, wherein the powder is injected into the air flow of the condensable gas pressurized by the heating unit and heat-treated.

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