JP2004053134A - Heat exchange system for fluid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchange system for fluid preferably used for heating or cooling foods wherein the quality of a product is highly influenced by a collapse of a solid contained in the fluid especially when the fluid is subjected to heat treatment. <P>SOLUTION: The system has a tank receiving pressurized gas to be kept at a prescribed pressure and storing the fluid, a heat exchanger communicated with the tank and heating/cooling the fluid fed from the tank, and a quantitative discharge device communicated with the exchanger, which includes a filling nozzle for quantitatively discharging the fluid heated/cooled by the exchanger at prescribed time intervals. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to a heat exchange system for heating or cooling a fluid, and more particularly to a method for continuously heat treating (heating or cooling) a fluid by passing it through a heat exchanger. It relates to a suitable heat exchange system.
[0002]
[Prior art]
Tube heat exchangers, plate heat exchangers, etc. are used for continuous heat treatment of fluids.However, in a heat exchange system incorporating this type of heat exchanger, a rotary pump or A pump source such as a mono screw pump is considered to be an essential element, and the pump source generally feeds the fluid into the heat exchanger.
[0003]
In particular, for food and medicine, strict control of the heat treatment time is required. As a means for this, control of the pump source is performed, thereby reducing the time required for the fluid to pass through the heat exchanger. Try to keep it constant.
[0004]
[Problems to be solved by the invention]
However, when a rotary pump or the like is incorporated in the heat exchange system, for example, when an attempt is made to heat-treat a solid-liquid mixture including a solid and a liquid, the rotary pump causes a “collapse” in which a part of the solid is lost. I will. Such a problem of “collapse” of solid matter cannot be overlooked in the food industry, for example, because it is a problem related to product quality. Due to such problems, the application range of the conventional heat exchange system has been limited.
[0005]
It is another object of the present invention to provide a heat exchange system which does not require a power pump for transfer such as a rotary pump in order to feed a fluid into the heat exchange system.
[0006]
A further object of the present invention is to provide a heat exchange system that can be suitably applied to a system having a fixed-quantity discharger that fills a retail container with a heat-treated fluid downstream of the heat exchange system. It is in.
[0007]
It is another object of the present invention to provide a heat exchange system suitable for heating or cooling food products in which "collapse" of solids contained in the solid-liquid mixture has a great effect on product quality.
[0008]
[Means for Solving the Problems]
In order to achieve such a technical problem, according to the present invention,
A tank for receiving a supply of pressurized gas, being kept at a predetermined pressure, and containing a fluid;
A heat exchanger communicating with the tank and heating or cooling the fluid supplied from the tank;
A constant-rate discharger including a filling nozzle communicating with the heat exchanger and discharging a predetermined amount of the fluid heated or cooled by the heat exchanger at predetermined time intervals. A body heat exchange system is provided.
[0009]
According to the present invention, the fluid in the tank is supplied to the heat exchanger by the internal pressure of the tank, and the fluid heated or cooled in the heat exchanger is supplied by the constant-rate discharger at a predetermined time interval in a predetermined amount. Is discharged, so that the time required for the fluid to pass through the heat exchanger is strictly controlled. Therefore, unlike the related art, there is no need for a pump for feeding the fluid to the heat exchanger and its control.
[0010]
Therefore, the heat exchange system according to the present invention not only heats or cools a liquid or paste-like fluid, but also treats a solid-liquid mixture, but uses a pump source such as a rotary pump as in the past. Since the problem of “collapse” of the solid does not occur, the solid-liquid mixture can be suitably heated or cooled by the heat exchange system of the present invention.
[0011]
The above and other objects and advantages of the present invention will be apparent from the following detailed description of preferred embodiments of the present invention.
[0012]
【Example】
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
[0013]
First embodiment (FIG. 1 )
FIG. 1 shows a heat exchange system 1 according to a first embodiment. The system 1 has a pressurized tank 2 connected to an air source, and the pressure in the pressurized tank 2 is regulated by a regulator 3. The heat exchange system 1 also includes a double-pipe tube heat exchanger 6 (pipe inner diameter: 23 mm, pipe length: 1600 cm, material: (A hot water is used as a heat medium), and a fixed-quantity discharger 8 connected to a downstream end of a tubular heat exchanger 6 via a pipe 7. The metering discharger 8 includes an inlet valve 9, a measuring piston 10 provided downstream of the inlet valve 9, and a filling nozzle 11 provided downstream of the measuring piston 10, and is discharged from the filling nozzle 11. The collected fluid is stored in a retail container (for example, a pouch) 12.
[0014]
The operation of the fixed-quantity discharger 8 is as follows. When the fluid that has been heat-treated (heated or cooled) by the heat exchanger 6 reaches the metered discharger 8, first, the inlet valve 9 is opened and the fluid is drawn into the measuring piston 10. After metering with the metering piston 10, the inlet valve 9 is closed and then the fluid is pushed out from the metering piston 10 to the filling nozzle 11. By the above operation, the fixed amount discharger 8 discharges the heat-treated fluid quantitatively. In addition, the inlet valve 9, the metering piston 10, and the filling nozzle 11 are controlled to operate at a predetermined cycle, for example, a cycle of 20 to 40 times / minute, by a signal from an external control device.
[0015]
By controlling the fixed-quantity discharger 8 as described above and operating the fixed-quantity discharger 8 in a fixed cycle, the passage time of the solid-liquid mixture through the tubular heat exchanger 6, that is, the heat treatment time is strictly controlled. can do. Although the tube heat exchanger 6 is used in the heat exchange system 1 of the embodiment, a plate heat exchanger may be incorporated instead.
[0016]
According to the system 1 having a relatively simple configuration without providing a pump source and controlling the pump source as in the related art, it is possible to heat or cool a liquid or paste-like fluid as in the related art. Can be. In order to control the heat treatment time of such a fluid, the flow rate distribution is taken into account, for example, based on the velocity of the fluid passing through the central portion in the cross section of the tubular heat exchanger 6, Various parameters may be set so that the passage time becomes a predetermined value.
[0017]
Further, as described above, the system 1 of the embodiment does not have a pump source, so even if a solid-liquid mixture containing a solid and a liquid is heat-treated, the problem of “collapse” of the solid caused by the pump is eliminated. Does not occur. Therefore, by using the system 1 of the embodiment, it is possible to perform heat treatment even on a solid-liquid mixture which is considered difficult with the conventional system, particularly a solid-liquid mixture having a high solid content. When heat-treating a solid-liquid mixture, a tube heat exchanger is generally preferable to a plate heat exchanger.
[0018]
Here, regarding the continuous heat treatment of the solid-liquid mixture using the system 1 of the embodiment, the most preferable treatment method will be described in detail below.
[0019]
A solid-liquid mixture in which a solid and a liquid are mixed has a flow property close to that of a liquid when the density of the solid is small, but conversely, when the density of the solid is large, a gap between adjacent solids is increased. The liquid easily slips through. When the phenomenon of "slip-through" of such a liquid occurs, there is a difference between the time required for the liquid to pass through the heat transfer tube and the time required for the solid to pass through the heat transfer tube. It is impossible to perform a uniform heat treatment. However, if the phenomenon of “slip-through” of the liquid can be suppressed, the solid and the liquid around the solid can be moved together.
[0020]
From the above point of view, (1) the solid-liquid mixture is pumped by gas pressure and passed through a heat exchanger; (2) the solid is adjusted to a dense state; and (3) the viscosity of the liquid is adjusted. It is preferable to combine the elements, so that the solid-liquid mixture is uniformly heated without substantially causing a flow velocity distribution inside the tubular heat exchanger 6 and suppressing the above-mentioned liquid “slip-through” phenomenon. Or it can be cooled.
[0021]
In performing such treatment, the relationship between the density of the solid matter and the viscosity of the liquid has a correlation with the flow rate that passes through the heat exchanger, and it is difficult to specify uniformly with numerical values. If it is fast enough, the viscosity of the liquid may be relatively small. Conversely, if the flow rate is relatively slow, it is desirable to make the viscosity of the liquid relatively large. The viscosity of the liquid may be adjusted using starch, a thickener, or the like. The solid matter may have a size that can pass through the tube heat exchanger 6.
[0022]
Generally, the inner diameter of the heat transfer tube constituting the tube heat exchanger 6 is preferably 10 mm to 25 mm, and the length of the heat transfer tube depends on the transfer speed of the solid-liquid mixture (passing through the heat transfer tube). The speed may be determined in consideration of the solid-liquid mixture speed) and the heat treatment conditions.
[0023]
Examples of foods of the solid-liquid mixture include corn soup containing corn grains, porridge containing rice grains, or tapioca, beverages containing small solids such as white ball dumplings, and the like.As solids contained therein, For example, beef, pork, chicken and other meats, fish and shellfish and other seafood, carrots, potatoes, pumpkin, peppers, onions and other vegetables, corn and other grains, soybeans, peas and other beans, and other granular products. Things and the like.
[0024]
Examples of the thickener include a heat-resistant thickening polysaccharide such as gellan gum, xanthan gum, and sodium alginate, and modified starch. According to experiments, the viscosity of the liquid is preferably from 700 mPa · s to 4000 mPa · s, more preferably from 900 mPa · s to 3000 mPa · s, and most preferably, in order to suppress the above “slip-through” phenomenon of the liquid. It is good to be a viscous liquid of 1100 mPa · s to 2000 mPa · s. In order to obtain such a viscosity, for example, the content ratio of the thickener to the solid-liquid mixture necessary for adjusting the viscosity of a liquid such as water depends on the type of the thickener, but may be 0.1% by weight. % To 2.0% by weight.
[0025]
The dense state of the solid in the solid-liquid mixture may be adjusted by adjusting the content ratio of the solid. That is, the solid-liquid mixture contains 30% by weight or more of solids, more preferably 35% to 80% by weight, still more preferably 40% to 70% by weight, and most preferably 45% to 65% by weight. , A solid and a liquid.
[0026]
As described above, by adjusting the solid-liquid mixture, the solid-liquid mixture flows downstream in the tubular heat exchanger 6 while maintaining the relative positional relationship between the solids and the liquid. To move towards. That is, the solid-liquid mixture can be uniformly heat-treated by the tube heat exchanger 6 while suppressing the occurrence of the flow velocity distribution and the phenomenon of “slip-through” of the liquid.
[0027]
Specifically, using the system 1 of the first embodiment, 50 parts by weight of green peas (whole grains, average particle diameter 7 mm), 49.5 parts by weight of water, and 0.5 part by weight of a thickener (Hereinafter, simply a mixture) with a viscous liquid (about 1100 mPa · s (B-type viscometer manufactured by Toki Sangyo Co., Ltd., rotor No. 3, measured at a product temperature of 25 ° C.)) in which xanthan gum was dissolved. .
[0028]
The mixture adjusted as described above was charged into the tank pressurized tank 2 and mixed. Next, after adjusting the pressure in the pressurized tank 2 to 0.3 MPa with the air regulator 3, the valve 4 is opened, and the mixture in the tank 2 is transferred to the double-pipe tube heat exchanger 6 via the pipe 5. Heat treatment was performed by pressure feeding, and the mixture after the heat treatment was filled into a retail pouch via the fixed amount discharger 8. The temperature of the mixture passing through the heat exchanger 6 was 90 ° C., and the time required to pass through the heat exchanger 6 was 13.3 minutes (average flow rate during this time was 500 g / min).
[0029]
According to the above conditions, the mixture was continuously heat-sterilized, and the product contained in the retail pouch 12 was confirmed. As a result, no fading was observed on the green peas, and there was no overheating odor and there was collapse. No green peas were found.
[0030]
As described above, by causing the fixed quantity discharger 8 to communicate with the tubular heat exchanger 6 and opening the fixed quantity discharger 8 for a predetermined period of time in a predetermined cycle, the mixture pumped to the tubular heat exchanger 6 is It moves inside the heat exchanger 6 intermittently.
[0031]
FIG. 2 is a diagram for explaining this state. Areas A, B, C,... Defined by wavy lines extending in the vertical direction in FIG. 3 indicate the solid-liquid mixture contained in the retail container 12 by one operation of the fixed amount discharging device 8. As can be understood from the figure, the mixture suppresses the occurrence of the flow velocity distribution in the tube heat exchanger 6 of the system 1, and the solid-liquid mixture in the region A extrudes the solid-liquid mixture in the region B downstream thereof. In this way, it moves intermittently like frame advance. In other words, in the tube type heat exchanger 6, the solid-liquid mixture moves downstream while maintaining the relative positional relationship between the solids S and the liquid L, and the solid-liquid mixture is discharged. By controlling 8, it is possible to strictly control the heating or cooling of the solid-liquid mixture through the tube heat exchanger 6.
[0032]
Second embodiment (FIG. 3)
FIG. 3 shows a heat exchange system 20 of the second embodiment. The system 20 of the second embodiment has a configuration in which another line (second line 24) is added to the system 1 of the first embodiment. Here, the same elements as those included in the system 1 of the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
[0033]
That is, the heat exchange system 20 of the second embodiment includes the above-described system 1 of the first embodiment as a main line. Here, a storage tank 23 connected via valves 21 and 22 to the system 1 of the first embodiment is added. Similarly, the storage tank 23 may be added to the system 1 (FIG. 1) of the first embodiment described above.
[0034]
In the system 20 of the second embodiment, a second line 24 is added to a first line (the system of the first embodiment) 1, and the second line 24 is provided with a mixing tank 25 containing soup and a mixing tank 25. 25 includes a pipe 27 connected via a valve 26.
[0035]
The pipe 27 is provided with a rotary pump 28, a tube heat exchanger 29, a homogenizer 31 interposed in a pipe 30 connected to a downstream end of the heat exchanger 29, and a downstream side of the homogenizer 31. And a second storage tank 38 connected to the pipe 30 via a valve 39. The downstream end of the pipe 30 is connected to the common filling nozzle 11, whereby the first line 1 and the second line 24 are joined at the common filling nozzle 11.
[0036]
The fixed-quantity discharger 8 has a valve 13 provided on the downstream side of the measuring piston 10 in addition to the configuration described in the first embodiment, and an inlet valve 40 is provided in the pipe 30 of the second line. A second metering piston 41 provided downstream of the inlet valve 40 and a valve 42 provided downstream of the metering piston 41.
[0037]
The system 20 of the second embodiment mixes the solid-liquid mixture measured by the first metering piston 10 of the first line 1 and the liquid component measured by the second metering piston 41 of the second line 24 to share the same. A retail container (for example, a pouch) 12 is filled through the filling nozzle 11.
[0038]
Regarding the operation of the system 20 of the second embodiment, a soup with green peas will be described as an example. In the first line 1, as described in the first embodiment, the viscosity of the viscous liquid containing the green peas is adjusted, and the solid green peas are also adjusted to have a high density and stored in the tank 2. Is done.
[0039]
The mixing tank 25 of the second line 24 contains the soup raw material of the soup containing green peas, which is a product, and the soup raw material is mixed in the mixing and stirring tank 25 to prepare a soup. Next, the valve 26 is opened and the rotary pump 28 is operated, so that the soup in the mixing tank 25 is transferred to the tube heat exchanger 29 via the pipe 27 and passed through the tube heat exchanger 29. The soup was heat sterilized.
[0040]
The flow rate of the soup passing through the tube heat exchanger 29 is 4500 g / min. Next, the sterilized soup is sent to a homogenizer 31 via a pipe 30, and subjected to a homogenization treatment by the homogenizer 31. Next, the homogenized soup is transferred to the fixed amount discharger 8.
[0041]
In the fixed amount discharger 8, first, the inlet valve 9 is opened, and the green peas and the viscous liquid are drawn into the first measuring piston 10. After measuring with the measuring piston 10, the inlet valve 9 is closed, the valve 13 is opened, and the green piece and the viscous liquid are supplied from the first measuring piston 10 to the common filling nozzle 11.
[0042]
On the other hand, the soup in the second line 24 is sent to the common filling nozzle 11 with the inlet valve 40 opened and drawn into the second metering piston 41, and then the inlet valve 40 is closed and the valve 42 is opened. The inlet valves 9 and 40 and the valves 13 and 42 are opened and closed at a rate of 25 times / minute by a signal from an external control device. In this common filling nozzle 11, the materials supplied from the first line 1 and the second line 24 are mixed, and the green peas having a ratio of 10 parts by weight of green peas, 10 parts by weight of viscous liquid and 180 parts by weight of soup are mixed. The pouch 12 is filled with 200 parts by weight of soup.
[0043]
During operation of the system 20 of the second embodiment, if any malfunction occurs in the peripheral device such as the common filling nozzle 11 and a filling seal device (not shown) for some reason, the first tube type heat exchanger 6 performs the heat sterilization process. The solid-liquid mixture thus obtained is stored in the first storage tank 23, and the soup heat-sterilized by the second tube heat exchanger 29 is stored in the second storage tank 38.
[0044]
The above operation is continued until the operation failure of the common filling nozzle 11 and the like is eliminated. During this time, in the pipe 7 (first line 1), switching is performed between pressure feeding of the green peas and the viscous liquid from the tube heat exchanger 6 side and reverse transfer from the fixed quantity discharging device 8 side. This switching is performed by opening and closing the valve 22 and the valve 21. In this embodiment, the switching frequency is 25 times / minute, which is the same as the opening / closing frequency of the inlet valve 9. By providing the storage tank in this way, the pressurized tank 2 can intermittently pump the green peas and the viscous liquid to the tube heat exchanger 6. Therefore, even if a malfunction occurs in the filling nozzle or a peripheral device such as a filling sealing device (not shown), the green peas and the viscous liquid can be collected in the storage tank, so that overheating is avoided. On the other hand, for the soup, while the filling nozzle 11 and the like have stopped discharging the fluid due to a malfunction or the like, the inlet valve 40 of the fixed amount discharger 8 is closed, the valve 39 is opened, and the heat treatment is completed. The soup is stored in the second storage tank 38.
[0045]
As will be understood by those skilled in the art from the above description, if the viscosity or solid density of the solid-liquid mixture heated or cooled using the first line 1 is not suitable as a product as it is, the heat-treated mixture is subjected to the second heat treatment. By mixing the liquid component heat-treated in the line 24, the viscosity of the solid-liquid mixture of the product can be reduced, and the density of the solid can be reduced to obtain a product having a desired viscosity and density.
[0046]
A plate heat exchanger or any other heat exchanger may be used as the heat exchanger 29 in the second line 24, and instead of the pump 28, instead of the tank 25, as in the first line 1. Alternatively, a tank connected to an air source and regulated by a regulator may be used. Further, one second line 24 is added to the first line 1, but one or more lines similar to the second line 24 may be further added.
[0047]
The first line 1 and the second line 24 can process different fluids, respectively, and are particularly suitable for liquids that are susceptible to change in viscosity (for example, viscous liquids that have been given a viscosity by kuzu, potato starch, etc.). ), The heat exchange treatment conditions can be changed according to the components such as a fluid containing a heat-sensitive component (eg, a seasoning solution containing a flavor) or a fluid that easily causes emulsification (a sauce or soup containing an oil or fat). Suitable for heat-exchanging two or more desired fluids. Further, since the fluids are mixed by the common filling nozzle, each fluid is easily mixed uniformly.
[0048]
Of these, a more specific description of the case of treating a liquid that is likely to cause emulsification is as follows. A sauce or soup containing fats and oils such as a tomato sauce is subjected to heat exchange treatment in the first line 1, and separately from the heat exchange treatment such as a flavor. The liquid containing weak components is subjected to heat exchange treatment in the second line 24, and the two are mixed by the filling nozzle 11 and filled into a retail container and sealed, so that the liquid such as the soup or sauce containing the oil and fat passes through the pump. The heat exchange treatment can be performed without causing the emulsification caused by the passage of the pump to be suppressed, and a source and a soup with good coloring can be obtained, while the deterioration of the flavor component contained in another liquid is suppressed. Thus, a liquid food such as a soup or a sauce with good coloring and aroma can be obtained.
[0049]
In addition, the above-mentioned system includes a method in which both the first line 1 and the second line 24 heat-treat a solid-liquid mixture as a fluid. In this case, the second line 24 may be changed to the substantially same configuration as the first line 1 by omitting the pump 28 from the second line 24. For example, when applied to the production of a pulp containing jelly mixed with pulp and jelly and pulp cut into a hole such as grape or litchi, a solid-liquid mixture containing the pulp and a viscous liquid is used as the first liquid. The heat exchange treatment is performed in the line 1, the solid-liquid mixture obtained by mixing the jelly and the viscous liquid is subjected to the heat exchange treatment in the second line 24, and the two are combined by the common filling nozzle 11 and filled into the retail container 12. As a result, it is possible to select a line having a pipe diameter according to the size of the solid matter and perform a heat exchange treatment suitable for each solid matter, and furthermore, the pulp does not collapse, and the pulp and jelly are measured. Retail containers can be filled with high precision.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a heat exchange system according to a first embodiment.
FIG. 2 is a view for explaining a flow form of a solid-liquid mixture when a preferred method of applying the system of the first embodiment to heating or cooling of the solid-liquid mixture is adopted.
FIG. 3 is a schematic configuration diagram of a heat exchange system according to a second embodiment.
[Explanation of symbols]
1. Heat exchange system of the first embodiment (first line)
2 Pressurized tank 3 Regulator 6, 29 Tube type heat exchanger 8 Quantitative discharger 20 Heat exchange system 24 of second embodiment 24 Second line 25 Mixing tank 28 Rotary pump 23, 38 Storage tank S Solid L Liquid

Claims (5)

A tank for receiving a supply of pressurized gas, being kept at a predetermined pressure, and containing a fluid;
A heat exchanger communicating with the tank and heating or cooling the fluid supplied from the tank;
A constant-rate discharger including a filling nozzle communicating with the heat exchanger and discharging a predetermined amount of the fluid heated or cooled by the heat exchanger at predetermined time intervals. Body heat exchange system. The heat exchange system according to claim 1, further comprising a storage tank for storing the fluid that has been heated or cooled in the heat exchanger when the fixed-quantity ejector stops discharging. The heat exchange system according to claim 1, wherein the heat exchanger is a tube heat exchanger. 4. At least one second line added to the heat exchange system according to any one of claims 1 to 3 and joined at the filling nozzle,
The second line is
A tank containing a second fluid;
A second heat exchanger communicating with the tank and heating or cooling the second fluid supplied from the tank;
A fixed-quantity discharger that is in communication with the second heat exchanger and includes the filling nozzle as a common filling nozzle. The heat exchange system according to claim 4, wherein the second line further includes a pump provided between the tank containing the second fluid and the second heat exchanger.

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