JPH03221755A - Device for liquid heat treatment - Google Patents

Abstract

PURPOSE:To permit an efficient and uniform heating at a high heating temperature without causing burning by heating liquid, with stirring, in an indirect heating device when the liquid is subjected to the indirect heating. CONSTITUTION:Fixed stirring mechanisms 8 are provided in a liquid passage 63 of each of the inner cylinders 6 through which the liquid to be indirectly heated is passed. The fixed stirring mechanism 8 consists of a shaft part 81 provided at the central part of the cross section of the passage 63 and a blade 82 projecting from the outer periphery thereof. The end of the shaft part 81 adapted to be arranged upstream the liquid being treated in the passage 63 is formed into a conical shape having a sharp or curved end, whereby the flow of liquid is impinged against the end 81a of the shaft part so as to be turned aside toward the inner walls of the inner cylinder 6. A hot water or vapor is used as an indirect heating medium and this medium is introduced into an uppermost outer cylinder 5-1 from its inlet 74. Since the passages 71 of all units are interconnected through communicating pipes 75 and 76 at their outlets, a flow of the medium is produced through all the passages 71 and the medium is discharged from an outlet 77 of a lowermost outer cylinder, thereby subjecting the liquid in the inner cylinders 6 to indirect heating.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat treatment apparatus used for sterilizing or denaturing liquids.

[Prior Art] As a heat treatment device for the purpose of sterilizing or denaturing a liquid, for example, a highly viscous liquid such as concentrated fish extract, soy milk, or moromi for brewing, indirect heating means using a conventional heat exchanger, A method of heating a liquid by combining a direct heating means that brings water vapor and liquid into direct contact has been used.

In the conventional heat treatment method described above, a plate heater type heat exchanger is mainly used as the heat exchanger of the indirect heating means.

[Problem 8 to be solved by the invention] In the notebook heater type heat exchanger used in the above-mentioned prior art, the liquid flows between the heat plates in a layered manner. There is no exchange of liquid between the two, and this tendency is particularly strong for highly viscous liquids.

For this reason, the outer layer that comes into contact with the liquid plate is constantly exposed to high temperatures, which may cause scorching or, in order to prevent scorching, it is necessary to prevent excessive heating, and there is a limit to the heating temperature. . Therefore, the heating burden on the second-stage direct heating means increases, and the amount of water vapor condensed also increases, resulting in a disadvantage that the water content of the treatment liquid tends to increase.

The present invention has been made to solve the above-mentioned problems, and its purpose is to eliminate burning of the liquid to be treated and to heat-treat the liquid to a high temperature with minimal increase in moisture. A liquid heat treatment device that efficiently exchanges heat in the indirect heating means, reduces the heating burden on the direct heating means, and further heats the temperature at each stage under optimal conditions according to the physical properties of the liquid to be treated. is to provide.

[Means for Solving the Problems] Means for solving the above-mentioned problems include means for circulating the liquid to be treated and indirectly heating it with an outer heating medium that has both bottoms with the flow path of the liquid; provided downstream of the heating means,
a fixed stirring mechanism for stirring the liquid in the processing liquid flow path of the indirect heating means; the fixed stirring mechanism is located at the center of the cross section of the flow path; The fixed agitation mechanism of the shaft and the blades is composed of a shaft portion having a length in the axial direction at a portion thereof, and blades projecting radially outward from the shaft portion and having an angle in the axial direction. A plurality of them are arranged spaced apart in the flow path.

[Effect by the above means] According to the above means, during indirect heating, the liquid is stirred by a fixed stirring mechanism in the flow path, that is, a shaft provided in the flow path, and a shaft portion provided in the flow path, which protrudes outward in the radial direction. The mixture is stirred by blades having angles in the axial direction, heat is exchanged evenly in each part, and the flow is not laminar, so burning of the outer layer is prevented and efficient heating is achieved. As a result, the heating burden in the next stage of direct heating using water vapor, etc. is reduced, the increase in moisture in the liquid can be suppressed as low as possible, and the indirect heating temperature can be set to the optimum condition according to the physical properties of the liquid. Can be heat treated.

[Embodiment] Next, an embodiment of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a schematic explanatory diagram of the device according to the present invention, FIG. 2 is a vertical side view of the indirect heating device, FIG. 3 is a vertical side view of the direct heating device, and FIG. 4 is a second implementation of the heating device. Example diagram, 5th
The figure is a diagram of the third embodiment.

In FIG. 1, reference numeral 1 denotes a storage tank for processing liquid. A positive displacement pump 2, for example, is provided downstream of the tank 1, and the liquid in the tank 1 is pumped through a line 3 to an indirect heating device 4.

The indirect heating device 4 is as shown in FIG. 2, and FIG. 2 shows a unit thereof.

The unit 5 consists of an inner cylinder 6 through which a liquid to be heat-treated flows, and an outer cylinder 7 surrounding the outer periphery of the inner cylinder 6, and an indirect heating medium passage 71 is formed between the inner and outer cylinders. In the example,
Three combinations of inner and outer cylinders 6 and 7 are arranged vertically in parallel 5-1.
5-2.5-3, the downstream end of the inner cylinder 6 of the combination body 5-1, the upstream end of the inner cylinder 6 of the combination body 5-2, and the downstream end of this and the inner cylinder 6 of the combination body 5-3. A horizontal U-shaped connecting pipe 9 is connected to each upstream end.
and the liquid circulation passage formed by the inner cylinder 6;
Connect through.

A mounting flange 61 is provided at the upstream end of the inner cylinder 6, that is, the upstream end of the inner cylinder of the combination 5-1, and a mounting flange 61 is provided at the upstream end of the inner cylinder of the combination 5-1.
Similarly, mounting flanges 62 are provided at the downstream ends of the inner cylinders 6 of No. 3, respectively. Closing lids 72 and 73 are provided at both axial ends of each outer cylinder 7, and an indirect heating medium inlet 74 is provided on the upstream outer periphery of the outer cylinder 7 of the upstream combination 5-1. A flange is provided at the end so as to protrude upward and outward in the radial direction.

A communication pipe 75 is provided between the downstream end of the outer cylinder 7 and the upstream end of the outer cylinder 7 of the next stage combination 5-2.
, 7, and a communication pipe 76 connects the downstream end of the outer cylinder 7 of the combination body 5-2 and the upstream end of the outer cylinder 7 of the final stage combination body 5-3. Make a continuous connection. As a result, the medium passages 71 within the outer cylinder 7 are interconnected. Under the outer cylinder 7 of the final stage, at the flow end, a medium outlet part 77 is provided with a flanse at the end so as to protrude downward and outward in the radial direction.

A fixed stirring mechanism 8 is provided in the liquid passage 63 of each inner cylinder 6 through which the liquid to be indirectly heated flows. The fixed stirring mechanism 8 includes a shaft portion 81 provided at the center of the cross section of the passage 63, and blades 82 protruding from the outer periphery of the shaft portion 81. The shaft portion 81 is formed into a conical shape with a sharp point or a cone at the upstream end where the processing liquid flows from the passage 63, and the flowing 1lJ2 body collides with the shaft portion tip 81a and moves outward in the radial direction. In other words, the flow is divided in the direction of the wall surface of the inner cylinder 6.

On the other hand, the wing pieces 82 are arranged radially around the outer periphery of the shaft portion 81, for example, at 9
Four wing pieces 82 are provided at 0° intervals, and the outer end portions of the wing pieces 82 are connected to the inner wall surface of the inner cylinder 6, and the shaft portion 81 is fixed and supported at the center of its cross section. The wing pieces 82... are twisted so as to form an angle in the axial direction and are inclined at a predetermined angle with respect to the axial direction, and the angled wing pieces 82... It is configured to efficiently stir at five speeds.

A plurality of the fixed stirring mechanisms 8 described above are arranged in the passage 63 in the inner cylinder 6 and spaced apart from each other in the axial direction.

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 into the outer cylinder inlet 74 of the final stage 5-1, and the medium is passed through the passage 71 of each unit.
. . . are connected by communication pipes 75 and 76 at each outlet, so that they flow through each passage 71 and are discharged from the -stage outlet 77, thereby indirectly discharging the liquid in the inner cylinder 6. Heat. On the other hand, the processing liquid pumped from the pump 2 flows from upstream to downstream in the passage 63 in the inner cylinder 6, and is liquidized by the blades 82 of the fixed stirring mechanism 8 in the passage 63. The flow is twisted and flows in the downstream direction, and then reaches the fixed stirring mechanism at the next stage, where it is twisted, and this process is repeated in order to be efficiently stirred and sent downstream. Therefore, the liquid flow does not become a laminar flow, and the outer layer, middle layer, and inner layer are stirred without any speed and move while contacting the inner wall of the inner cylinder 6, and heat is exchanged efficiently and heated. Become.

In the above, by selecting the number of blades 82 constituting the stirring mechanism, the twist angle, that is, the angle of inclination in the axial direction, etc., settings are made to heat the liquid under optimal conditions according to the physical properties of the liquid. be able to.

By the way, a control valve 13 is provided in the downstream part of the heating medium supply line 1o near the inlet part 74, and a temperature sensor 14 is provided in the upstream part of the connecting pipe 12.
5 inputs information from the sensor 14, and based on the judgment of the controller 15, the control valve 13 is controlled to open and close, or is adjusted to open and close, using a diaphragm 131, for example, to control the flow rate, adjust the supply amount of the medium, and adjust the heating temperature. control.

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

FIG. 3 shows an example of the direct heating device 16.

The direct heating device 16 includes a main body 17 made of a tube through which preheated liquid flows, and has connecting flanges 171 and 172 at both axial ends thereof for connection to a connecting pipe. Above the main body 17 is a water vapor distribution chamber 18 made of a pipe body with both ends closed in parallel.
A direct heating medium inlet 181 such as saturated steam is provided on the upper wall of one end of the heating medium, and a connecting flange 182 is provided at the end of the inlet. The bottom wall 184 of the pipe body 183 forming the distribution chamber 18 and the top wall 173 of the main body 17 are connected to each other by a plurality of introducing vibes 19 .
... has a small diameter and is inclined in this direction because the liquid flows from left to right in the figure, and each vibrator 1
9... are parallel. The upstream end 174 of the main body 17 is connected to the downstream end of the communication pipe 12 described above, and the liquid subjected to the indirect heat treatment described above flows into the passage 175 of the main body 17 and connected to the connecting pipe 20 connected to the downstream end 176. It is discharged into the hold tube 21 via.

By the way, from the inlet section 181 through the supply line 22,
For example, saturated steam is supplied into the distribution chamber 18, and the distribution chamber 1
Saturated water vapor is introduced into the passage 175 from 8 through the vibrator 19, and the direction of the water vapor jetting out is inclined in the forward direction with respect to the flow direction of the liquid, so that the water vapor is efficiently mixed into the liquid. , efficiently heats liquids. Nao passage 175
A stirring mechanism similar to that described above may be provided inside the container, and direct heating may be performed while stirring.

Note that 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 out from the direct heating device 16 is
The information is detected by a sensor 25 provided in the connecting pipe 20, and the information is input to the thermo controller 26, and the control valve 23 is controlled to open and close using a diaphragm 231, for example, or the opening degree is adjusted to control the flow rate, thereby controlling the supply amount of the heating medium. The heating temperature is controlled by adjusting the

Processing liquid transport line 27 for the hold tube 21 described above
The downstream end of this line 27 is connected to an indirect cooling device 28.
The cooling device 28 has a similar structure to the indirect heating device 4, and circulates cold water or the like between the inner cylinder 29 and the outer cylinder 30 surrounding it to cool the heated liquid being transported. do. At the downstream end of the indirect cooling device 28, a final transport line 3 is provided.
1 is connected, and the line 31 is connected to the product storage tank 32. A pressure sensor 33 is installed in the line 31 to detect the transportation pressure of the liquid, and if necessary, the pressure controller 3
4, the control valve 35 provided downstream of the sensor 33 is adjusted. Then, by setting the pressure in the processing line appropriately higher than the evaporation temperature in the direct heating device using the pressure controller 34, boiling of the processing liquid in the line can be prevented.

The above constitutes a liquid heat treatment line.

FIG. 4 shows a second embodiment of the heat treatment apparatus, in which the same parts as in the previous embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, the process liquid transport line 27 downstream of the hold tube 21 described above is provided with a process of concentrating the process liquid as the next process, for example, a vacuum evaporator 40 is provided, and the downstream end of the line 27 is connected to this. do. The heat-treated liquid is introduced into the evaporator 40, and at the time of introduction, a sensor 41 is connected to the line 27.
, a pressure controller 42, and a control valve 43 are provided to control the pressure.

The evaporator 40 is provided with a line 44 for removing separated water,
An ejector 45 is attached to this to discharge evaporated water.

By doing so, it is possible to evaporate and remove the moisture in the processing liquid that has increased in the direct heating device 16, and also to lower the temperature of the processing liquid, and the liquid concentrated in the evaporation device is
The product is stored in the product storage tank 32 via the line 31 via the valve 46.

Incidentally, if further temperature adjustment of the processing liquid is required, a cooling device may be provided in the next step of the vacuum evaporation device described above, if necessary.

FIG. 5 shows a third embodiment of the heat treatment apparatus, and since the basic structure is the same as that of the first embodiment, the same parts are denoted by the same reference numerals, and detailed explanation of each part will be omitted.

This embodiment detects the temperature downstream of the direct heating device 16,
Thermo controller 26 that directly controls the temperature of the heating medium
and a pressure controller 34 that detects the pressure between the indirect cooling device 28 and the product storage tank 32 and controls the pressure of the processing line in the form of a closed container (pipe line). 26 detected values are transmitted, and the temperature of the liquid to be treated and its pressure are linked.

[Effects of the Invention] As is clear from the above, according to the present invention, when a liquid is indirectly heated, it is heated while being stirred in the indirect heating device, so there is no inconvenience such as burning as in the past, and the heating temperature is also high. It is highly efficient and can heat each part evenly.

In particular, a fixed agitation mechanism installed in an indirect heating device has a shaft member in the center of the flow path of the processing liquid, and blades are provided on this shaft so as to protrude outward in the radial direction. Since the structure is such that a plurality of blades are installed at an angle and spaced apart in the axial direction, the processing liquid is twisted in the process of passing through the blades due to the action of the blades, and this process is repeated in the process of flowing in the axial direction. , the processing liquid is agitated at five speeds in each of the outer layer, middle layer, and inner layer, and moves while each layer is in contact with the inner wall in the indirect heating device,
Efficient heat exchange is achieved, and each part can be heated evenly, without burning, and efficiently.

In addition, as mentioned above in the previous section, as a result of efficient heating, the heat burden in the next stage of direct heating is reduced, and as a result, while the liquid is heated to a high temperature, there is no increase in condensed water. In addition to being able to minimize the temperature and obtain a good product, the temperature can be heated at each stage under optimal conditions depending on the physical properties, and the indirect heating device has a simple configuration with the above-mentioned fixed stirring mechanism. There are many advantages such as being able to achieve the above.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a schematic explanatory diagram of an apparatus according to the present invention, FIG. 2 is a vertical side view of an indirect heating device, and FIG. 3 is a vertical side view of a direct heating device. Figure, 4th
The figure shows a second embodiment of the heating device, and FIG. 5 shows a third embodiment of the heating device. In the drawing, 4 is an indirect heating means, 5 is a unit thereof, and 63
8 is a fixed stirring mechanism, 81 is a shaft, 82 is a blade, and 16 is a direct heating means.

Claims (1)

[Claims] A means for circulating a liquid to be treated and indirectly heating it with an external heating medium defined by a flow path for the liquid; and a direct heating means provided downstream of the indirect heating means for heating the indirectly heated treatment liquid. A fixed stirring mechanism for stirring the liquid is provided in the processing liquid flow path of the indirect heating means, and the fixed stirring mechanism includes a shaft portion having a length in the axial direction at the center of the cross section of the flow path; , and blades projecting outward in the radial direction from the shaft and having an angle in the axial direction, and a plurality of fixed stirring mechanisms of the shaft and the blades are arranged spaced apart in the flow path. A liquid heat treatment device characterized by: