JPH0615953B2 - Indirect heating device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an indirect heating device used for sterilizing or denaturing a liquid.

[Prior Art] As a heat treatment device for the purpose of sterilizing and denaturing highly viscous liquids such as concentrated fish meat extract, soy milk, and mash for brewing,
Conventionally, a liquid is heat-treated by combining an indirect heating device using a heat exchanger and a direct heating device for directly contacting water vapor with a liquid.

In the above heat treatment method, a plate heater type heat exchanger is mainly used as an indirect heating device.

[Problems to be Solved by the Invention] In the plate heater type heat exchanger that constitutes the indirect heating device used in the above-described conventional technique, since the liquid flows between the heat plates in a layered manner, the contact of the outer layer that contacts the plates is performed. There is no liquid exchange between the central part and the central part, and this tendency is strong especially for highly viscous liquids.

Therefore, the outer layer portion that comes into contact with the liquid plate is always exposed to a high temperature, and burning occurs, or it is necessary to prevent excessive heating to prevent burning, and there is a limit to the heating temperature. .

Therefore, there is a drawback that the heating load of the second stage direct heating means provided downstream of the indirect heating device is increased, the condensed water of steam is also increased, and as a result, the water increase tendency of the treatment is increased.

The present invention has been made to solve the above problems, the object of which is a highly viscous heat-treated liquid,
It eliminates the sticking of the treated liquid and can efficiently and indirectly heat the treated liquid. By combining this with a direct heat treatment device, the heating load on the direct heating device is reduced and the liquid is sterilized. Another object of the present invention is to provide an indirect heating device suitable for use in a heat treatment device that performs modification, etc.

[Means for Solving the Problems] Means for solving the above-mentioned problems include an inner cylinder through which the liquid to be heated is circulated, and an outer cylinder provided so as to surround and separate the outer periphery of the inner cylinder. A heating medium passage is formed in the space between the inner and outer cylinders, and the inner cylinder has a shaft portion disposed in the central portion of the cross section and having an axial length, and a radially outward projecting portion from the shaft portion. That is, a plurality of fixed stirring mechanisms each including a plurality of blades having an angle in the axial direction are provided separately in the axial direction.

[Operation of the above means] The liquid flowing into the indirect heating device is agitated by the fixed agitation mechanism in the flow path, that is, a plurality of blades having an angle in the axial direction that protrudes radially outward around the shaft portion, The liquid is uniformly heat-exchanged and heated, and does not form a laminar flow, so that the outer layer is prevented from being scorched and is efficiently heated.

[Example] FIG. 1 is a vertical side view of an indirect heating apparatus according to the present invention, FIG. 2 is a schematic explanatory view of a heat treatment apparatus incorporating the indirect heating apparatus according to the present invention, and FIG. It is a longitudinal section showing an example of a direct heating device used for a treatment device.

The indirect heating device 4 is as shown in FIG. 1. In this embodiment, an example used for a liquid heat treatment device as shown in FIG. 2 is shown.

The indirect heating device 4 is configured by connecting a plurality of units 5 as shown in the figure. The unit 5 is composed of an inner cylinder 6 through which the liquid to be heat-treated flows, and an outer cylinder 7 concentrically arranged so as to surround the outer circumference of the inner cylinder with a space therebetween. Indirect heating is provided between the inner and outer cylinders 6, 7. The example tightened in FIG. 1 in which a passage 71 through which the medium flows is formed is provided with three units 5-1, 5-2, 5-3 that are vertically parallel to each other and are composed of units 5 ... , A downstream end of the inner cylinder 6 of the unit 5-1 and an upstream end of the inner cylinder 6 of the unit 5-2, and a downstream end thereof and an upstream end of the inner cylinder 6 of the unit 5-3 are respectively connected in a horizontal U shape. The pipes 9 are connected for communication, and the liquid circulation passages 61 formed in the inner cylinders 6 of the units 5 are connected.

A mounting flange 62 is provided at the most upstream end of the inner cylinder 6 of the unit 5, that is, the upstream end of the inner cylinder of the unit 5-1, and the downstream end of the inner cylinder 6 of the unit 5-3 at the downstream portion. A mounting flange 63 is also provided on the part. Then, a lid 7 is provided on each end of the outer cylinder 7 of each unit 5 in the axial direction.
2 ..., 73 ... are respectively provided to close both ends in the axial direction,
The passages 71 of the indirect heating medium, which are partitioned and sealed, are formed on the outer circumference of each inner cylinder 6.

On the outer periphery of the upstream portion of the outer cylinder 7 of the most upstream unit 5-1, an indirect heating medium inlet portion 74 is provided so as to stand upward with a mounting flange 75 at the end portion. The downstream portion of the outer cylinder 7 of the unit 5-1 and the unit 5-2 of the next stage
The upstream part of the outer cylinder 7 is connected by a communication pipe 76, and the downstream part of the unit 5-2 and the upstream part of the outer cylinder 7 of the last unit 5-3 are connected by a communication pipe 77. Then, an outlet portion 78 for the indirect heating medium is provided so as to hang downward in the radial direction at the downstream portion of the outer cylinder 7 of the unit 5-3 at the final stage.
Includes a flange 79 as described above.

As described above, the indirect heating medium passages 71 of the units 5-1, 5-2, 5-3 are communicated with each other, and the heating medium flows into the passage 71 of the unit 5-1 from the inlet portion 74, and the passage 7
1, the inner cylinder 6 on the inner side is heated, flows into the passage 71 of the intermediate unit 5-2 via the communication pipe 76, and then passes through the communication pipe 77 to the passage of the final stage unit 5-3. 71
It flows in and is discharged from the outlet 78. In the process,
The inner cylinders 6 of each unit 5 are heated.

Fixed stirring mechanisms 8 are provided in the liquid circulation passages 61 of the inner cylinders 6 in which the liquid to be indirectly heat-treated flows.

The fixed stirring mechanism 8 is composed of a shaft portion 81 provided in the central portion of the cross section of the passage 61, and a plurality of blades 83 ... Protrudingly provided on the outer periphery of the shaft portion 81. The shaft portion 81 has a tip end portion in the upstream direction in which the treatment liquid flows in the passage 61 is formed into a sharp or curved conical shape, and the liquid flowing in the passage 61 collides with the tip end portion 82 of the shaft portion in the radial direction. The flow is divided outward, that is, toward the wall surface 64 of the inner cylinder 6.

The above-mentioned wing pieces 83 are radially provided on the outer periphery of the shaft portion 81, for example, at four 90 ° intervals. The wing 83 ...
The outer end portion thereof is connected to, firmly fixed to, and supported by the inner wall surface 64 of the inner cylinder 6. The blades 83 are twisted so as to make an angle in the axial direction and are provided at a predetermined angle with respect to the axial direction, and the processing liquid flowing in the passage 61 has an angled blade 83. ... is configured to efficiently and universally stir.

A plurality of the above fixed stirring mechanisms 8 ... Are arranged in the passage 61 in the inner cylinder 6 at a predetermined interval in the axial direction. Each unit 5
The fixed agitation mechanism 8 applied to the passage 1 in each inner cylinder 6 of
Is provided, the processing liquid in FIG. 1 flows in from the left end of the passage 61 of the inner cylinder 6 of the unit 5-1 and flows rightward through it, and is inverted by the connecting pipe 9. In the passage 61, it flows from right to left, and therefore the shaft portion 81 directs the tip end portion 82 toward the right side which is the upstream side, and is inverted by the connecting pipe 9 at the downstream end,
The most upstream unit 5-1 flows through the passage 61 of the unit 5-3.

The indirect heating medium used in the indirect heating device is, for example, hot water or steam, and is made to flow from the line 10 of the liquid heat treatment device shown in FIG. 2 into the outer cylinder inlet portion 74 of the unit 5B, and the medium is Since the passages 71 of each unit are connected by the communication pipes 76 and 77 at their respective outlets, they flow in the respective passages 71 and are discharged from the outlet 78 of the unit 5-A. Indirect heating of liquid flowing through.

On the other hand, the processing liquid pumped from the pump 2 is the unit 5
The blades 8 of the fixed stirring mechanism 8 in the passage 61 flow into the passage 61 in the inner cylinder 6 of A and flow in the passage 61 from upstream to downstream.
The liquid flow is twisted by 3 and flows in the downstream direction, then reaches the fixed stirring mechanism 8 in the next stage, is twisted in this portion, and is sequentially repeated to be efficiently stirred and sent to the downstream, The inner cylinder 6 of the unit 5B is reached.

The liquid flowing in the inner cylinder 6 is diverted to the outside because the tip 82 of the shaft 81 is as described above, and collides with the blades 83 ... And is twisted because it has an angle in the axial direction. In the example, since the four blades 83 ... Are provided around the shaft 81, the liquid flow is divided into four and twisted and agitated, so that the liquid flow does not become a laminar flow. The outer layer, the intermediate layer, and the inner layer are uniformly stirred and moved while being in contact with the inner wall of the inner cylinder 6, and are efficiently heat-exchanged and heated.

In the above, the number of blades 83 ...
By selecting the twist angle, that is, the angle of inclination in the axial direction, it is possible to set heating under optimum conditions according to the physical properties of the liquid.

In this way, the processing liquid that has flowed into the inner cylinder 6 by the fixed stirring mechanism 8 is efficiently and uniformly stirred and indirectly heated by the heating medium flowing outside the inner cylinder 6.

By the way, further explaining the heat treatment apparatus in which the indirect heating apparatus 4 according to the present invention is used according to FIG. 2, the control valve 13 is provided at the downstream portion of the heating medium supply line 10 near the inlet portion 74, while the control valve 13 is connected. A temperature sensor 14 is provided on the upstream side of the pipe 12, and the thermo controller 15 is provided with a temperature sensor 14.
4, the control valve 13 is opened / closed by the judgment of the controller 15, for example, the opening / closing control or opening / closing adjustment is performed by the diaphragm 131 to control the flow rate, adjust the supply amount of the medium, and control the heating temperature. .

A direct heating device 16 is provided downstream of the indirect heating device 4 described above, and is connected to each other through a connecting pipe 12.

As the direct heating device 16, for example, the one shown in FIG. 3 is used.

The direct heating device 16 is provided with a main body 17 formed of a pipe body through which the preheated liquid flows, and connection flanges 171 and 172 to the connecting pipes at both axial ends thereof. The main body 17 is provided with a water vapor distribution chamber 18 composed of a tube body closed at both ends in parallel, and a direct heating medium inlet 181 for saturated water vapor or the like is provided on an upper wall at one end of the main body 17 and is connected to the inlet end. Flange 1
82 is provided. Tube 18 forming distribution chamber 18
The bottom wall 184 of No. 3 and the upper wall 173 of the main body 17 are connected by a plurality of introduction pipes 19 ..., The pipes 19 ... Have a small diameter, and the liquid flows in the direction in which the liquid flows, that is, from left to right in the figure. Therefore, the pipes 19 are inclined in this direction, and the pipes 19 are parallel to each other. The upstream end 174 of the main body 17 is connected to the communication pipe 12 described above.
Is connected to the downstream end of
It flows into the passage 175 of the main body 17 and is discharged to the hold tube 21 via the connecting pipe 20 connected to the downstream end 176.

By the way, from the inlet 181 through the supply line 22,
For example, saturated steam is supplied to the distribution chamber 18,
Saturated steam is introduced into the passage 175 through the pipes 19 ... And the jetting direction of the steam is inclined in the forward direction with respect to the flowing direction of the liquid. Heat efficiently.

A control valve 23 is provided in the supply line 22 and a filter 24 is provided upstream of the valve 23. Then, the temperature of the liquid after the heat treatment immediately after flowing directly from the heating device 16 is
The information detected by the sensor 25 provided in the connecting pipe 20 is input to the thermo controller 26, and the control valve 23 is opened / closed by the diaphragm 231, or the opening is adjusted to control the flow rate to control the supply amount of the heating medium. Is adjusted to control the heating temperature.

The above-mentioned hold tube 21 is used for various liquid transport lines 27
And the downstream end of this line 27 is connected to the indirect cooling device 28.
The cooling device 28 has a structure similar to that of the indirect heating device 4, and cool water or the like is circulated between the inner cylinder 29 and the outer cylinder 30 surrounding the inner cylinder 29 to cool the transported liquid after the heat treatment. To do. At the downstream end of the indirect cooling device 28, the final transportation line 3
1, the line 31 is connected to the product storage tank 32, and the line 31 is provided with a pressure sensor 33 to detect the transport pressure of the liquid, and the pressure controller 34 is used to detect the sensor 33 when necessary. The control valve 35 provided downstream is adjusted. Then, the pressure controller 34 appropriately sets the pressure in the processing line higher than the evaporation temperature in the direct heating device, so that boiling of the processing liquid in the line can be prevented.

With the above, a liquid heat treatment line was constructed.

[Advantages of the Invention] As is apparent from the above, according to the present invention, when performing indirect heat treatment of a highly viscous liquid, the indirect heating device is provided with a fixed stirring mechanism in the liquid flow passage and is provided at the center of the inner cylinder. Plural wing pieces are provided on the circumference of the provided shaft portion, and the wing pieces are twisted so as to make an angle in the axial direction, so that the liquid flowing under pressure into the passage is twisted by the wing pieces. In addition, since a plurality of them are provided separately in the axial direction, the twisting action is repeated from the upstream side to the downstream side. Therefore, the liquid does not become a laminar flow, and the outer layer, the intermediate layer, and the inner layer are evenly stirred by the blades and move while being in contact with the inner wall of the inner cylinder forming the passage, thereby efficiently performing heat exchange. It can be heated, and the liquid can realize efficient indirect heating without charring evenly in each part. Further, the above is provided with a shaft part in a pipe-shaped inner cylinder, Since the wing pieces are provided so as to form an angle in the axial direction and a plurality of the wing pieces are provided so as to be separated from each other in the axial direction, there are great advantages such as the epoch-making advantage as described above with a simple structure.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a vertical sectional side view of an indirect heating device according to the present invention, and FIG. 2 is a schematic view of a heat treatment device incorporating the indirect heating device according to the present invention. Explanatory drawing and FIG. 3 are longitudinal sectional views showing an example of a direct heating apparatus used in the heat treatment apparatus. In the drawing, 4 is an indirect heating device, 5 is a unit of the indirect heating device, 6 is an inner cylinder, 61 is a liquid flow passage, 7 is an outer cylinder, 71
Is an indirect heating medium passage, 8 is a fixed stirring mechanism, 81 is a shaft portion,
83 is a wing piece.

Claims (1)

[Claims] 1. An inner cylinder through which a liquid to be heated is circulated, and an outer cylinder provided so as to surround and surround the outer circumference of the inner cylinder, and a heating medium passage is formed in a space between the inner and outer cylinders. Fixed in the inner cylinder, which is arranged in the central portion of the cross section and has a shaft portion having a length in the axial direction and a plurality of winglets projecting radially outward from the shaft portion and having an angle in the axial direction. An indirect heating device, wherein a plurality of stirring mechanisms are provided axially separated from each other.