Heat exchanger

Abstract

Provided is a heat exchanger having a structure that is advantageous in improving the total heat transfer coefficient that indicates heat exchange efficiency. Three flow paths, a first flow path (11), a second flow path (21), and a third flow path (31), are provided in a space formed between an inner cylinder (61) and an outer cylinder (52) and are spirally wound. They are divided by an inner heat transfer body (41) and an outer heat transfer body (51), and heat exchange is performed via these heat transfer bodies. These heat transfer bodies are spirally wound, the cross-sectional shape in an axial cross-sectional view is a thread shape, and they are assembled in a threaded manner. The flow path area of the first flow path (11) is changed by changing the shape of the male thread and the female thread, and the second flow path (21) and the third flow path (31) are spirally formed and heat exchange is performed via the heat transfer bodies.

Description

Technical Field

[0001] This invention relates to heat exchangers, the purpose of which is to heat or cool liquids, especially slurries containing dispersed solids, high-viscosity liquids, or fluids containing vapor, using fluids such as refrigerants, heat transfer media, or steam. Background Technology

[0002] For processes in chemical and food manufacturing, as well as in the production of colorants or inkjet printers, there are often requirements for rapid cooling or high-speed heating. Additionally, there is a need to minimize the necessary installation space, reduce the size of the equipment itself, and seek high-performance heat exchangers. Furthermore, there is a requirement for minimal adhesion, excellent cleanability, pressure resistance, corrosion resistance, and low cost.

[0003] Previously, shell-and-tube reactors with multiple workbenches, as disclosed in Patent Document 1, were known. These reactors had at least two types of zones, each corresponding to the system requirements, facilitating heat removal from or supply to the system. The reactor included a group of reaction zones containing a catalyst for promoting the reaction, and additionally, tubes for simultaneously removing or supplying heat.

[0004] However, in the configuration described in Patent Document 1, it is difficult to clean when adhesions or the like occur inside the pipe, and it is impossible to easily confirm whether the cleaning status has been completed.

[0005] Furthermore, due to the large amount of heat medium retained on the shell side, overshoot or undershoot is prone to occur, making it essentially an old-fashioned heat exchanger, thus hindering a revolutionary increase in the overall heat transfer coefficient. Moreover, because the tubes are mounted on the tube sheet, it is difficult to accommodate reactions involving repeated expansion and contraction with respect to heat. Additionally, coating or plating is practically impossible inside the thin tubular heat transfer tubes, and structurally, it is also difficult to apply corrosion-resistant materials in other flow paths; improvements are sought from the perspective of corrosion resistance. In particular, it is practically impossible to coat or plating the interior of the aforementioned heat transfer tubes with corrosion-resistant materials; even if it were possible, mass production would be poor, resulting in products that are not cost-effective.

[0006] Patent document 2 describes a heat exchanger characterized by forming a liquid-side heat transfer tube with a roughly triangular cross-sectional shape into a coil shape, and arranging a refrigerant-side heat transfer tube in a coil shape around its outer periphery, thereby connecting the liquid-side heat transfer tube and the refrigerant-side heat transfer tube. However, the heat transfer area is too small, limiting its application to water heaters and the like, and hindering miniaturization, ease of cleaning, high performance, and low cost.

[0007] Patent document 3 describes a heat exchanger that includes a first flow path forming member having a container shape and a second flow path forming member that can be detachably disposed inside the first flow path forming member relative to the first flow path forming member. The diameter of the inner circumferential surface of the container-shaped peripheral wall of the first flow path forming member gradually decreases from the top to the bottom, and a first flow path for the flow of heat exchange liquid is formed in the peripheral wall. Between the inner circumferential surface of the first flow path forming member and the outer circumferential surface of the second flow path forming member, a spiral second flow path for the flow of heat exchange liquid to exchange with the heat exchange liquid is formed by these inner and outer circumferential surfaces.

[0008] However, because the flow path gradually decreases, the flow velocity through the heat transfer surface also gradually changes. Therefore, it is difficult to apply in general industry. Furthermore, in heat exchange accompanied by boiling, there are many stagnant gas sites, which can easily cause dry out.

[0009] Patent Document 4 describes a tubular flow module comprising at least two concentric tubes with a helical shape. This tubular flow module is disclosed as being suitable for flow reactors with heat exchange functions. The module is characterized by inner and outer tubes being assembled in a spiral shape, defining a flow path for the fluid between the tubes. However, the average flow direction is axial, and the aim is to create an improved embolic flow condition from the flow generated in all directions, producing a near-perfect helical flow for the main fluid flow, rather than to improve the overall heat transfer coefficient, which represents heat exchange efficiency. Specifically, in Patent Document 4, the configuration is such that even though the tubes are formed in a helical shape, by setting the width of the flow path formed between the tubes to be equal, a helical flow is added to the axial flow to create an improved embolic flow condition, rather than creating a helical flow to improve heat exchange efficiency.

[0010] Prior art literature

[0011] Patent Document 1: Japanese Patent Publication No. 2012-529626

[0012] Patent Document 2: Japanese Patent Application Publication No. 2013-24536

[0013] Patent Document 3: Japanese Patent Application Publication No. 2015-81716

[0014] Patent Document 4: Japanese Patent Publication No. 2015-502842 Summary of the Invention

[0015] The problem that the invention aims to solve

[0016] In view of the above, the objective of the present invention is to provide a heat exchanger having a structure that is advantageous for improving the overall heat transfer coefficient representing heat exchange efficiency.

[0017] Another objective of the present invention is to provide a heat exchanger having a structure suitable for suppressing the presence of processed material or the generation of gas stagnation in the heat transfer section.

[0018] Another objective of this invention is to provide a heat exchanger with good cleanability.

[0019] Another objective of this invention is to provide a heat exchanger capable of decomposition.

[0020] In addition, the present invention also aims to provide a heat exchanger that can also be used for coating application.

[0021] Solution for solving the problem

[0022] The present invention relates to an improvement of a heat exchanger, wherein the heat exchanger has three flow paths, namely a first flow path, a second flow path, and a third flow path, which are spirally wound in the space formed between the inner and outer cylinders of the same core. Heat exchange occurs between the first fluid (the fluid being processed) flowing through the first flow path and the second and third fluids flowing through the second and third flow paths, respectively, via a heat transfer medium.

[0023] In this invention, the heat transfer body is fitted into the gap formed by the inner cylinder and the outer cylinder and is spirally wound. The cross-sectional shape in the axial cross-sectional view is threaded. It is assembled in a threaded manner. The flow area of ​​the first flow path is changed by changing the shape of the male thread and the female thread. Furthermore, the second and third flow paths are formed in a spiral shape and the heat exchange is carried out through the heat transfer body.

[0024] It can be implemented in the following way: the heat transfer body is fitted in the gap formed by the inner cylinder and the outer cylinder and is spirally wound. The cross-sectional shape in the axial sectional view is threaded. It is assembled in a threaded manner. The shape of the male thread and the female thread is changed by changing the angle of the thread teeth of the male thread and the female thread.

[0025] Furthermore, the present invention provides a heat exchanger configured such that an inner cylindrical heat transfer body is provided as a male threaded portion and an outer cylindrical heat transfer body is provided as a female threaded portion, wherein the heat transfer bodies are arranged in a threaded configuration, and a first flow path for a first fluid to flow is formed between the inner and outer heat transfer bodies. The heat exchanger includes a second flow path located inside the inner heat transfer body and a third flow path located outside the outer heat transfer body. Heat exchange occurs between the second fluid flowing through the second flow path and the first fluid via the inner heat transfer body, and heat exchange occurs between the third fluid flowing through the third flow path and the first fluid via the outer heat transfer body. The invention is characterized by the following: In the present invention, the first flow path is a spirally wound flow path, and the ratio (α / β) of the maximum flow path width (α) to the minimum flow path width (β) of the first flow path in the radial direction is 2 or more (2 < α / β < ∞).

[0026] The present invention can be implemented in the following manner: the heat exchanger has an inner cylinder and an outer cylinder with the same core, the inner heat transfer body is fixed on the outside of the inner cylinder, the outer heat transfer body is fixed on the inside of the outer cylinder, the second flow path is set between the inner cylinder and the inner heat transfer body, and the third flow path is set between the outer cylinder and the outer heat transfer body.

[0027] It can be implemented in the following way: both the second flow path and the third flow path are spiral flow paths.

[0028] Furthermore, the present invention can be implemented in the following manner: the space generated by the difference between at least one of the angle (θ1) of the thread tooth of the inner heat transfer body of the male thread portion and the angle (θ2) formed by the two threaded sides of the outer heat transfer body of the female thread portion, and the height difference between the height of the thread tooth of the inner heat transfer body of the male thread portion and the height of the thread tooth of the outer heat transfer body of the female thread portion, is the first flow path.

[0029] Preferably, the first flow path, the second flow path, and the third flow path do not have horizontal sections where the first fluid, the second fluid, and the third fluid may stagnate.

[0030] Alternatively, it can be implemented in the following way: multiple spaces formed between the inner cylinder and the outer cylinder, which are configured as concentric, are provided in a concentric shape.

[0031] Preferably, the flow path through which the first fluid, including the first flow path described above, flows is coated with a corrosion-resistant material. Fluoropolymer coatings are an example of such corrosion-resistant materials.

[0032] The effects of the invention

[0033] The present invention provides a heat exchanger having a structure that is advantageous for improving the overall heat transfer coefficient representing heat exchange efficiency.

[0034] The present invention provides a heat exchanger having a structure suitable for suppressing the retention of processed material or gas in the heat transfer section.

[0035] This invention provides a heat exchanger with good cleanability.

[0036] This invention provides a heat exchanger with a structure that is easily decomposed.

[0037] This invention provides a heat exchanger that can also be used for coating applications.

[0038] To elaborate further, processes in chemical and food manufacturing, as well as in the production of colorants and inkjet printers, often involve rapid cooling or high-speed heating. The fluids being processed include large quantities of high-viscosity liquids, slurries containing microparticles, and adhering substances. Traditionally, the performance of a heat exchanger is expressed by its heat transfer area per unit volume and overall heat transfer coefficient. Furthermore, the larger the heat transfer area per unit volume and the higher the overall heat transfer coefficient, the better the performance and the greater the heat exchange efficiency.

[0039] According to the present invention, the heat transfer area per unit is significantly larger than in prior art. Furthermore, the heat transfer resistance or contamination coefficient at the heat exchange surface depends on the material or environment and is therefore omitted from explanation. However, to improve the overall heat transfer coefficient, the degree of turbulence at the heat exchange surface is the greatest factor. Various measures have been taken, such as increasing the flow velocity of the processed fluid and the heat medium or installing obstruction plates, but pressure loss becomes a problem in each case. Therefore, to minimize pressure loss and create a turbulent state, a spiral flow is effectively utilized together with the processed fluid and the heat medium. The spiral flow, influenced by centrifugal force, easily creates a turbulent state, increasing the Reynolds number, thereby enabling a heat exchanger with even higher performance in applications using convection.

[0040] Furthermore, in heating operations accompanied by evaporation, if gas stagnation occurs, the thermal conductivity drops to a low level comparable to that of a single-phase gas flow. This phenomenon, known as through-drying, occurs because the liquid film flowing along the heat transfer surface evaporates and disappears, allowing the gas phase to directly contact the heat transfer surface. Additionally, scaling up is indeed necessary; high performance is a given, and even large-scale operations require computational processing.

[0041] To address these issues, the relationship between the flow rate and pressure loss of the processed material was reconsidered, and the following structure was proposed: even with increased flow rate, the pressure loss will not become excessive. This is particularly effective for high-viscosity processed materials or easily settling slurries, with minimal contamination and adhesion.

[0042] In addition, by setting the heat transfer body to a roughly triangular shape, liquid stagnation and gas accumulation are eliminated, and the heat transfer area can be increased. The shape of the roughly triangular shape can be selected according to the physical properties of the non-corresponding processed object, which also provides design freedom.

[0043] In addition, the amount of processed material is small, making it easy to handle rapid heating or cooling. At the same time, the amount of heat medium or refrigerant is also small, thus achieving miniaturization, high performance, and easy control of the equipment.

[0044] Because of its very simple structure, it is easy to disassemble and assemble, and can also be coated with corrosion-resistant materials. Attached Figure Description

[0045] Figure 1 This is an axial cross-sectional view of the heat exchanger according to the first embodiment of the invention.

[0046] Figure 2 yes Figure 1 Enlarged sectional view of the main part.

[0047] Figure 3 (A) to (D) are axial cross-sectional views showing the main parts of a modified example of a heat exchanger according to an embodiment of the present invention. Detailed Implementation

[0048] The heat exchanger according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0049] (Regarding fluids)

[0050] In this embodiment, the fluid intended for heat exchange will be described as the first fluid F1. Since heat exchange involves the exchange of heat energy between two fluids, a master-slave distinction is not necessary; however, it is more common to describe processes aimed at heating or cooling a specific fluid. Therefore, in this embodiment, the flow path of the first fluid F1 intended for heating or cooling will be described as the first fluid F1. The fluid that exchanges heat with the first fluid F1 will be described as the second fluid F2. Furthermore, other fluids that exchange heat with the first fluid F1 will be described as the third fluid F3.

[0051] The first fluid F1 can be any fluid such as gas, liquid, slurry, or fluidized body, which can be used as the fluid being processed. For the second fluid F2 and the third fluid F3, examples of heat media include water vapor, hot water, cold water, and nitrogen. However, the types of these fluids should not be considered fixed; the first fluid F1 can be used as the heat medium, and the second fluid F2 or the third fluid F3 can be used as the fluid for heat exchange.

[0052] The inner shaft portion 63 provided at the upper and lower ends of the inner cylinder 61 is inserted into the fixed cylinder portion 64 provided at the upper and lower ends of the outer cylinder 62. The inner shaft portion 63 and the fixed cylinder portion 64 are fixed and combined. In this combined state, the positional relationship between the inner heat transfer body 41 and the outer heat transfer body 51 is also fixed.

[0053] (Summary of the first embodiment)

[0054] Figure 1 as well as Figure 2 The heat exchanger according to the first embodiment shown has an inner cylinder 61 and an outer cylinder 62 configured as concentric, and may also have other cylinders on the inner or outer side.

[0055] The space between the inner cylinder 61 and the outer cylinder 62 is divided into three spaces by the inner heat transfer body 41 and the outer heat transfer body 51. The inner heat transfer body 41 and the outer heat transfer body 51 are generally concentric cylindrical in shape, and they are also concentric with the inner cylinder 61 and the outer cylinder 62.

[0056] The space between the inner heat transfer body 41 and the outer heat transfer body 51 forms the first flow path 11, the space between the inner cylinder 61 and the inner heat transfer body 41 forms the second flow path 21, and the space between the outer cylinder 62 and the outer heat transfer body 51 forms the third flow path 31. These flow paths are all spirally wound and travel in the axial direction of the inner cylinder 61 and the outer cylinder 62.

[0057] The inner heat transfer element 41 is fixed to the inner cylinder 61, and the outer heat transfer element 51 is fixed to the outer cylinder 62, in order to maintain airtightness and liquid tightness, thereby separating the fluids in each flow path in a way that prevents them from mixing.

[0058] Heat exchange occurs between the first fluid F1 and the second fluid F2 via the inner heat transfer element 41, and between the first fluid F1 and the third fluid F3 via the outer heat transfer element 51.

[0059] The inner heat transfer element 41 is fixed to the outside of the inner cylinder 61 and can rotate as a whole, while the outer heat transfer element 51 is fixed to the inside of the outer cylinder 62 and can rotate as a whole.

[0060] The inner heat transfer element 41 is provided as a male threaded part, and the outer heat transfer element 51 is provided as a female threaded part. The two are assembled in a threaded manner. By rotating the inner heat transfer element 41 and the inner cylinder 61 relative to the outer heat transfer element 51 and the outer cylinder 62, they can be assembled together separately.

[0061] In the separated state, the flow path forming surface of the first flow path 11 is defined as being separated into the side of the inner heat transfer body 41 and the side of the outer heat transfer body 51.

[0062] (Regarding the inner heat transfer element 41 and the outer heat transfer element 51)

[0063] The inner heat transfer element 41 travels axially while spiraling along the outer circumference of the inner cylinder 61, and the cross-sectional shape in the axial sectional view is approximately triangular.

[0064] The outer heat transfer element 51 travels axially along the inner circumference of the outer cylinder 62 in a spiral shape, and the cross-sectional shape in the axial sectional view is approximately triangular.

[0065] Both have the same pitch and lead angle. The inner heat transfer element 41 is designated as the male thread portion, and the outer heat transfer element 51 is designated as the female thread portion. The two are then assembled. Therefore, the inner heat transfer element 41 will be described as a male thread, and the outer heat transfer element 51 will be described as a female thread.

[0066] The inner heat transfer element 41 has a valley bottom 44 with the smallest outer diameter, a peak top 45 with the largest outer diameter, a first inclined portion 42 and a second inclined portion 43 connecting the valley bottom 44 and the peak top 45, and is fixed to the inner cylinder 61 at the valley bottom 44. The outer heat transfer element 51 has a peak top 55 with the smallest inner diameter, a valley bottom 54 with the largest inner diameter, a first inclined portion 52 and a second inclined portion 53 connecting the peak top 55 and the valley bottom 54, and is fixed to the outer cylinder 62 at the valley bottom 54.

[0067] Furthermore, in this example, such as Figure 2 As shown in (A), the diameters of the valley bottom 44 and the peak top 55 are approximately the same, which can be implemented as a way for the two to come into contact. Alternatively, it can be implemented as follows: Figure 2 As shown in (B), the outer diameter of the valley bottom 44 of the inner heat transfer element 41 is slightly smaller than the inner diameter of the peak top 55 of the outer heat transfer element 51, leaving a gap between them. This gap becomes the minimum flow path width (β) of the first flow path 11, preferably, in such a way... Figure 2 In the case of contact as shown in (A), β = 0, in the case of contact as shown in (A) Figure 2 In cases where a gap exists as shown in (B), β≤4mm.

[0068] Furthermore, the angle (θ1) of the thread teeth formed by the first inclined portion 42 and the second inclined portion 43 of the inner heat transfer element 41 is greater than the angle (θ2) formed by the two threaded side surfaces formed by the first inclined portion 52 and the second inclined portion 53 of the outer heat transfer element 51. Therefore, as... Figure 2 As shown in (A), a space is formed between the first inclined portion 42 and the second inclined portion 43 of the inner heat transfer element 41 and the first inclined portion 52 and the second inclined portion 53 of the outer heat transfer element 51, and this space becomes the first flow path 11. Furthermore, this space is largest between the peak 45 of the inner heat transfer element 41 and the valley bottom 54 of the outer heat transfer element 51, defining the maximum flow path width (α) of the first flow path 11 in the radial direction. The ratio (α / β) of the maximum flow path width (α) to the minimum flow path width (β) of the first flow path 11 is preferably 2 or more, more preferably 10 or more, and when the valley bottom 44 contacts the peak 55, β = 0 and α / β = ∞.

[0069] Furthermore, in mathematics, a triangle refers to a shape where the two hypotenuses intersect at the vertex. However, in industrial production contexts such as metal sheet processing, a triangle typically has a curved vertex or a length along its axial direction. Therefore, the term "approximate triangle" should be understood not only as a mathematical triangle but also as a shape relevant to these industrial production processes. Additionally, when the top and valley sections have a length along their axial direction, the likelihood of fluid blockage increases with the length of this axial section; therefore, it is appropriate for the axial length to be less than the axial length of a single inclined section.

[0070] Next, regarding the thickness t of the inner heat transfer element 41 and the outer heat transfer element 51 (refer to...), Figure 2 Since heat exchange of fluid occurs between them (A), considering the efficiency of heat exchange, a thickness of 0.2 mm to 3 mm is preferred, and 0.5 mm to 2 mm is more preferred. The thickness of the inner cylinder 61 or the outer cylinder 62 can also be the same. However, it can also be changed considering the strength that functions as a structure, and is not limited thereto.

[0071] Alternatively, the inner heat transfer body 41 or the outer heat transfer body 51 can be described as a three-dimensional shape having at least one bent portion (in addition to a straight portion that bends at an angle, it also includes an arc-shaped bent portion, referred to as the bent portion). The three-dimensional shape has the following shape: having at least one bent portion, it can form a space (first flow path 11, second flow path 21, third flow path 31) on both its inner and outer sides, allowing fluid to flow. Specifically, the three-dimensional shape is a strip-shaped body having a shape like a polygonal prism or cylinder cut along its axial direction. In this example, the three-dimensional shape is a strip-shaped body having a shape like a quadrangular prism cut along its axial direction on the diagonal of a quadrilateral cross-section. The three-dimensional shape is wound around the outer peripheral surface of the inner cylinder 61 and the inner peripheral surface of the outer cylinder 62, respectively, with its upper and lower ends fixed to the outer peripheral surface of the inner cylinder 61 and the inner peripheral surface of the outer cylinder 62, respectively.

[0072] (Regarding the first path 11)

[0073] In this embodiment, the first flow path 11 is a polygonal space defined by the first inclined portion 42 and the second inclined portion 43 and the first inclined portion 52 and the second inclined portion 53 of the inner heat transfer body 41, which becomes the flow path of the first fluid F1, which is the main object of heat exchange.

[0074] The heat exchanger involved in this implementation method is such as Figure 2 As shown in (A), as previously described, the space between the peak 45 of the inner heat transfer element 41 and the valley 54 of the outer heat transfer element 51 defines the maximum flow path width (α) of the first flow path 11 in the radial direction. When the valley 44 contacts the peak 55, the minimum flow path width (β) is 0, becoming α / β = ∞. Therefore, the first fluid F1 becomes a completely spiral flow, repeatedly swirling while traveling axially. As a result, the flow path length for heat exchange or chemical reaction can be increased, and a high-performance heat exchanger can be achieved by effectively utilizing the spiral flow. That is, the spiral flow is affected by centrifugal force, which can easily create a turbulent state, thereby enabling a high-performance heat exchanger by increasing the Reynolds number. As a result, the overall heat transfer coefficient, which represents the heat exchange efficiency, can be improved.

[0075] In addition, such as Figure 2 In the case of (B), even if there is a gap between the valley bottom 44 and the peak top 55, by setting the ratio (α / β) of the maximum flow path width (α) to the minimum flow path width (β) of the first flow path 11 to 2 or more, and more preferably 10 or more, the fluid flowing axially due to short circuit can be minimized, and the overall flow becomes a spiral flow.

[0076] Specifically, the minimum flow path width (β) is preferably 0 mm to 4 mm, and the maximum flow path width (α) is preferably 4 mm to 75 mm, more preferably 10 mm to 50 mm. However, the shape and size of the space of the first flow path 11 are determined by the angle difference between the angle of the thread teeth (θ1) of the inner heat transfer body 41 and the angle (θ2) formed by the two thread sides of the outer heat transfer body 51. These angles can be changed according to the type of fluid or the purpose of processing.

[0077] In addition, such as Figure 3 As shown in (A), the outer heat transfer element 51 can be rotated at axial intervals, and although the figure is omitted, the inner heat transfer element 41 can also be rotated at axial intervals. In this case, the outer cylinder 62 located between the rotating outer heat transfer elements 51 becomes the valley bottom 54, and the first flow path 11 becomes the space surrounded by the first inclined portion 42, the second inclined portion 43, the first inclined portion 52, the second inclined portion 53, and the valley bottom 54.

[0078] If the axial length of the valley bottom 54 is increased, the cross-sectional area (flow path area) of the first flow path 11 can be increased, while the cross-sectional area (flow path area) of the third flow path 31 decreases. Therefore, the overall heat exchange rate can be taken into account and the balance between the two can be considered to determine the length and implement it.

[0079] The first inclined portion 42 and the second inclined portion 43 of the inner heat transfer element 41 or the first inclined portion 52 and the second inclined portion 53 of the outer heat transfer element 51 are appropriately straight in the axial sectional view, but they can also be curved, such as in an arc shape, or as... Figure 3 As shown in (B), the whole is composed of curves.

[0080] However, the aforementioned cross-sectional shapes are preferably those that do not allow for the retention of the processed material or gas, such as the first fluid F1. Preferably, unless there is a specific purpose, flat horizontal portions or recesses should be avoided, for example, in a part of the flow path.

[0081] In addition, it can also be like Figure 3 As shown in (C), the valley bottom 44 of the inner heat transfer element 41 is configured to have a length in the axial direction, and the inner heat transfer element 41 is implemented as a cylindrical body as a whole. In this case, the inner heat transfer element 41 is composed of a three-dimensional shape defined by the first inclined portion 42, the second inclined portion 43, and the peak 45, and a flat plate-shaped valley bottom 44, which together form a cylindrical body. Similarly, the outer heat transfer element 51 can also be implemented as a cylindrical body composed of a three-dimensional shape defined by the first inclined portion 52, the second inclined portion 53, and the peak 55, and a flat plate-shaped valley bottom 54.

[0082] In these cases, the inner heat transfer element 41 and the outer heat transfer element 51 can be implemented either without a gap between the valley bottom 44 and the inner cylinder 61 or between the valley bottom 54 and the outer cylinder 62, or with a gap (μ). When this gap (μ) is provided, it is appropriate to set it to 4 mm or less. If this gap (μ) is set too large, the amount of fluid flowing in a short-circuit manner instead of a spiral flow for the second fluid F2 or the third fluid F3 increases, which may lead to a decrease in heat exchange efficiency.

[0083] Assume that various fluids, such as gas, liquid, slurry, and fluidized body, are flowing as the first fluid F1 in the first flow path 11. Depending on the type of fluid, there is a possibility that high-viscosity substances or easily settling slurries may adhere to the first flow path 11. In this embodiment, the first flow path 11 has an approximately triangular axial cross-section and does not have any impassable narrow sections, thus creating a structure that can suppress adhesion.

[0084] Furthermore, when performing disassembly and cleaning, if the separation is performed by rotating the inner cylinder 61 and the inner heat transfer element 41 relative to the outer cylinder 62 and the outer heat transfer element 51 to disengage the threads, then for the first flow path 11, the inner peripheral surface of the first flow path 11 (the outer peripheral surface of the inner heat transfer element 41 and the inner cylinder 61) and the outer peripheral surface of the first flow path 11 (the inner peripheral surface of the outer heat transfer element 51 and the outer cylinder 62) are completely separated and exposed, and the angles exposed on these surfaces are all 90 degrees or more. Therefore, the first flow path 11 can be cleaned to every corner, and the state at the end of the cleaning is easily confirmed.

[0085] In contrast, when a circularly shaped coil is positioned between the inner circumference of the outer cylinder and the outer circumference of the inner cylinder, the gap inevitably becomes narrow. Even if the inner and outer cylinders are separated, if the coil-shaped heat transfer tube is not separated, when viewed from the aforementioned radial direction, the inner half of the coil-shaped heat transfer tube is obscured by the outer half and not directly exposed. As a result, it is difficult to clean all corners and it is impossible to easily check the cleaning status.

[0086] The material of each surface along the flow path of the first flow path 11 is selected to correspond to the type of the first fluid F1, such as metal. Furthermore, it is preferable to coat its surface with a corrosion-resistant material. Examples of corrosion-resistant coatings include enamel, fluoropolymer coatings, and ceramic coatings. In this case, if the corrosion-resistant material is processed after the inner cylinder 61 and the inner heat transfer element 41 are fixed, or after the outer cylinder 62 and the outer heat transfer element 51 are fixed, and then the two are screwed together, the entire inner surface of the first flow path 11 can be reliably coated.

[0087] (Regarding the second flow path 21)

[0088] The space between the inner heat transfer element 41 and the inner cylinder 61 forms a second flow path 21 with an approximately triangular axial cross-sectional shape. This second flow path 21, like the first flow path 11, is spirally wound, but unlike the first flow path 11, it is a closed space in the axial cross-sectional view. Therefore, it can maintain a closed state simply by being divided into two parts in a spiral manner as described above. However, since the second flow path 21 typically allows heat media such as water vapor, hot water, cold water, and nitrogen to circulate as a second fluid F2, the possibility of fluid adhesion is low, unlike the first flow path 11.

[0089] (Regarding the third flow path 31)

[0090] The space between the outer heat transfer element 51 and the outer cylinder 62 forms a third flow path 31 with an approximately triangular axial cross-sectional shape. This third flow path 31, like the first flow path 11, is spirally wound, but unlike the first flow path 11, it is a closed space in the axial cross-sectional view. Therefore, it can maintain its closed state simply by being divided into two parts in a spiral manner as described above. However, the third flow path 31 typically allows heat media such as water vapor, hot water, cold water, and nitrogen to circulate as a third fluid F3. Therefore, unlike the first flow path 11, the possibility of fluid adhesion is low.

[0091] In addition, the rotation directions of the first flow path 11, the second flow path 21, and the third flow path 31 can be different (e.g., clockwise and counterclockwise) or the same.

[0092] (Regarding inflows and outflows)

[0093] The first fluid F1 originates from the... Figure 1 The inflow portion 12 of the fixed cylinder portion 64 at the lower end flows into the spiral first flow path 11 through the annular flow path 65 inside it, and moves upward while spiraling, and flows out to the outside from the outflow portion 13 through the annular flow path 65 provided at the upper end of the fixed cylinder portion 64. In addition, multiple fluids can be mixed by providing multiple inflow portions 12 and annular flow paths 65, or fluids pre-mixed by a mixer (not shown) provided outside the system, such as a static stirrer or a continuous stirrer, can be introduced.

[0094] The second fluid F2 flows through Figure 1 The inflow portion 22 provided at the upper inner shaft portion 63 flows into the spiral second flow path 21, spirals downward while moving downward, and flows outward from the outflow portion 23 provided at the lower inner shaft portion 63.

[0095] The third fluid F3 is located at... Figure 1The inflow portion 32 near the upper end of the outer cylinder 62 flows into the spiral third flow path 31, spirals downwards while flowing outwards from the outflow portion 33 near the lower end of the outer cylinder 62.

[0096] In addition, the inflow and outflow sections of each flow path can be reversed.

[0097] The materials for each surface along the passage paths of the first fluid F1, second fluid F2, and third fluid F3, such as the first flow path 11, the second flow path 21, and the third flow path 31, can be selected from metals or other materials depending on the type of the first fluid F1 and the second fluid F2, but it is also preferable to coat their surfaces with a corrosion-resistant material. Examples of corrosion-resistant coatings include enamel, fluoropolymer coatings, and ceramic coatings.

[0098] (Other implementation methods)

[0099] This invention can be implemented with various modifications other than those described above. For example, the first flow path 11 can be constructed by making the height of the male thread formed by the inner heat transfer body 41 different from the height of the female thread formed by the outer heat transfer body 51. Specifically, it can also be implemented as follows: Figure 3 As shown in (D), the angle (θ1) of the thread teeth defined by the first inclined portion 42 and the second inclined portion 43 of the inner heat transfer body 41 is set to the same angle as the angle (θ2) formed by the two thread sides defined by the first inclined portion 52 and the second inclined portion 53 of the outer heat transfer body 51. Furthermore, the height of the thread teeth on the inner heat transfer body 41 side is reduced and the peak 45 is set to have a length in the axial direction. Thus, the space defined by the peak 45, the first inclined portion 52 and the second inclined portion 53 can also be used as the first flow path 11.

[0100] In addition, in the above embodiments, the inner cylinder 61 and the outer cylinder 62 are both implemented as cylindrical bodies, but they can also be implemented as tubes with convex and concave shapes that extend in a spiral shape, thereby increasing the cross-sectional area of ​​each flow path of the second flow path 21 and the third flow path 31.

[0101] Alternatively, although not shown in the figure, it can also be implemented in the following way: other cylinders are arranged inside or outside the inner cylinder 61 and the outer cylinder 62, and an inner heat transfer body 41 and an outer heat transfer body 51 are arranged between the inner cylinder and the outer cylinder, and multiple spaces for the above heat exchange are provided in a concentric shape.

[0102] Explanation of reference numerals in the attached figures

[0103] F1 First Fluid

[0104] F2 Second Fluid

[0105] F3 Third Fluid

[0106] 11 First flow path

[0107] 12 Inflow section

[0108] 13 Outflow part

[0109] 21 Second Flow Path

[0110] 22 Inflow section

[0111] 23 Outflow part

[0112] 31 Third Flow Path

[0113] 32 Inflow section

[0114] 33 Outflow part

[0115] 41 Inner heat transfer element

[0116] 42 First inclined section

[0117] 43 Second Inclined Section

[0118] 44 Valley Bottom

[0119] 45 Peak Top

[0120] 46. ​​Thread tooth angle θ1

[0121] 51. External heat transfer element

[0122] 52 First inclined section

[0123] 53 Second Inclined Section

[0124] 54 Valley Bottom

[0125] 55 Peak Top

[0126] 56. The angle θ2 formed by the two threaded sides

[0127] 61 Inner cylinder

[0128] 62 outer cylinder

[0129] 63 Inner shaft section

[0130] 64 Fixed cylinder section

[0131] 65 Circular Flow Path

Claims

1. A heat exchanger provided with three flow paths of a first flow path, a second flow path and a third flow path spirally wound in a space formed between an inner tube and an outer tube of a common core, in which a first fluid flowing through the first flow path, i.e., a processed flow body, exchanges heat with a second fluid flowing through the second flow path and a third fluid flowing through the third flow path via a heat transfer body, characterized in that the heat transfer body is fitted in a gap formed by the inner tube and the outer tube and spirally wound, a cross-sectional shape in an axial cross-sectional view is a thread shape, assembled in a thread shape, a flow path area of the first flow path is changed by changing a shape of a male thread portion and a female thread portion, and the second flow path and the third flow path are spirally formed to exchange the heat via the heat transfer body.

2. The heat exchanger according to claim 1, characterized in that the heat transfer body is fitted in a gap formed by the inner tube and the outer tube and spirally wound, a cross-sectional shape in an axial cross-sectional view is a thread shape, assembled in a thread shape, and a shape of the male thread portion and the female thread portion is changed by changing an angle of a thread of the male thread portion and the female thread portion.

3. A heat exchanger configured to provide a cylindrical inner heat transfer body as a male thread portion and a cylindrical outer heat transfer body as a female thread portion, the inner heat transfer body and the outer heat transfer body being combined in a thread shape, a first flow path for a first fluid to flow between the inner heat transfer body and the outer heat transfer body, a second flow path located on an inner side of the inner heat transfer body across the inner heat transfer body, and a third flow path located on an outer side of the outer heat transfer body across the outer heat transfer body, heat being exchanged between a second fluid flowing through the second flow path and the first fluid via the inner heat transfer body, and heat being exchanged between a third fluid flowing through the third flow path and the first fluid via the outer heat transfer body, characterized in that the first flow path is a flow path spirally wound, 4. The heat exchanger according to claim 3, characterized in that the second flow path is provided between the inner tube and the inner heat transfer body. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The third flow path is provided between the outer cylinder and the outer heat transfer body, The second flow path and the third flow path are spiral flow paths, The space generated by at least one of the difference in the angle between the angle (θ1) of the thread of the inner heat transfer body as the male screw portion and the angle (θ2) of the two thread flanks of the outer heat transfer body as the female screw portion and the difference in the height between the height of the thread of the inner heat transfer body as the male screw portion and the height of the thread of the outer heat transfer body as the female screw portion.

5. The heat exchanger according to any one of claims 1 to 4, wherein The first flow path, the second flow path, and the third flow path do not have a horizontal portion in which the first fluid, the second fluid, and the third fluid can stagnate.

6. The heat exchanger according to claim 1 or 2, wherein The space between the inner cylinder and the outer cylinder of the common core is provided as a plurality of common cores.

7. The heat exchanger according to claim 3 or 4, wherein The space between the inner cylinder and the outer cylinder of the common core is provided as a plurality of common cores.

8. The heat exchanger according to any one of claims 1 to 4, wherein The through flow path through which the first fluid flows including the first flow path is coated with a corrosion-resistant material.

9. The heat exchanger according to claim 8, wherein The coating with the corrosion-resistant material is fluororesin coating.

10. The heat exchanger according to claim 5, wherein The through flow path through which the first fluid flows including the first flow path is coated with a corrosion-resistant material.

11. The heat exchanger according to claim 6, wherein The through flow path through which the first fluid flows including the first flow path is coated with a corrosion-resistant material.

12. The heat exchanger according to claim 7, wherein The through flow path through which the first fluid flows including the first flow path is coated with a corrosion-resistant material.

13. The heat exchanger according to claim 10, wherein The coating with the corrosion-resistant material is fluororesin coating.

14. The heat exchanger according to claim 11, wherein The coating with the corrosion-resistant material is fluororesin coating.

15. The heat exchanger according to claim 12, wherein The coating with the corrosion-resistant material is fluororesin coating.

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