Superheated steam generator

Abstract

To effectively use radiation of heat from a superheated conductor tube to improve thermal efficiency and reduce the influence that the superheated conductor tube is cooled by water or steam introduced from an introduction port.SOLUTION: A pre-heating conductor tube 3 has a first pre-heating conductor tube 31 and a second pre-heating conductor tube 32 that are arranged concentrically around a closed magnetic circuit iron core 2. The conductor tubes 31, 32, 4 are arranged in the order of the second pre-heating conductor tube 32, a superheated conductor tube 4, and the first pre-heating conductor tube 31 from the inside in a radial direction, and are connected in series in the order of the first pre-heating conductor tube 31, the second pre-heating conductor tube 32, and the superheated conductor tube 4. The second pre-heating conductor tube 32 has a spiral short circuit part 32X short-circuited in an axial direction. A superheated steam generation device introduces water or steam from an introduction port P1 provided in the first pre-heating conductor tube 31, and derives superheated steam from a derivation port P2 provided in the superheated conductor tube 4 through the second pre-heating conductor tube 32.SELECTED DRAWING: Figure 1

Description

【Technical Field】 , , , 【0006】 , , , , 【0001】 The present invention relates to an apparatus for generating superheated steam. 【Background Art】 【0002】 As a conventional superheated steam generation apparatus, as shown in Patent Document 1, a first conductor tube and a second conductor tube are used as primary coils, and a third conductor tube (superheating conductor tube), which is a secondary coil, is provided between the first conductor tube and the second conductor tube. Specifically, an introduction port of the first conductor tube into which water is introduced is provided on one end side in the axial direction, and a discharge port of the third conductor tube from which superheated steam is discharged is provided on the other end side in the axial direction. Further, the second conductor tube and the third conductor tube are connected to each other at one end side in the axial direction. 【0003】 In this superheated steam generation apparatus, the first conductor tube and the second conductor tube are heated by energization, and are also heated by utilizing the heat radiation of the third conductor tube. Therefore, heat radiation from the third conductor tube to the outside of the apparatus can be reduced, and the thermal efficiency can be increased. 【0004】 However, in the above configuration, one end portion in the axial direction of the third conductor tube is cooled by the water introduced from the introduction port of the first conductor tube. As a result, the preheated water or steam flowing into the third conductor tube is cooled. Then, there are problems that the time required to superheat the superheated steam to a desired temperature becomes long, and the temperature of the superheated steam generated varies depending on the change in the amount of water. 【Prior Art Documents】 <00000​​​​​​​​​​​​​​​​​​Therefore, the present invention was made to solve the above problems, and its main objective is to improve thermal efficiency by effectively utilizing the heat dissipation of the superheated conductor tube, and to reduce the effect of cooling the superheated conductor tube by water or steam introduced from the introduction port. [Means for solving the problem] 【0007】 In other words, the superheated steam generating apparatus according to the present invention is a superheated steam generating apparatus that generates superheated steam by heating a conductive tube by electromagnetic induction and heating the water or steam flowing through the conductive tube, comprising a closed magnetic circuit core, a primary coil to which an AC voltage is applied, a spiral preheating conductive tube arranged around the closed magnetic circuit core, and a secondary coil through which an induced current flows, a spiral superheating conductive tube arranged around the closed magnetic circuit core, wherein the preheating conductive tube comprises a first preheating conductive tube and a second preheating conductive tube arranged concentrically around the closed magnetic circuit core The device has conductive tubes, each of which is arranged in the order of the second preheating conductive tube, the superheating conductive tube, and the first preheating conductive tube from the radially inner side, and the first preheating conductive tube, the second preheating conductive tube, and the superheating conductive tube are connected in series in that order, the second preheating conductive tube having a short-circuit section that is short-circuited in the spiral axial direction, and water or steam is introduced from an introduction port provided in the first preheating conductive tube, and superheated steam is discharged from an outlet provided in the superheating conductive tube via the second preheating conductive tube. 【0008】 In this type of superheated steam generator, a first preheating conductor tube and a second preheating conductor tube are used as the primary coil, and a superheating conductor tube, which is a secondary coil, is provided between the first and second preheating conductor tubes. As a result, the first and second preheating conductor tubes are heated by electric current, and are also heated by utilizing the heat dissipation from the superheating conductor tube. This reduces heat dissipation from the superheating conductor tube to the outside of the device, thereby increasing thermal efficiency. In particular, in this invention, since the second preheating conductor tube has a short-circuit section that is short-circuited in the spiral axial direction, the preheated water or saturated steam flowing into the superheating conductor tube can be heated by Joule heating due to the short-circuit current. As a result, the effect of cooling the superheating conductor tube by the water or steam introduced from the introduction port is reduced, and the time required to heat the superheated steam to the desired temperature can be shortened. Furthermore, in response to temperature changes of superheated steam due to changes in the amount of water, the superheated steam can be heated to the desired temperature regardless of changes in the amount of water. Here, the first and second preheating conductor tubes forming the primary coil can have their heat generation ratio, heat transfer area ratio to the fluid, and fluid velocity ratio adjusted by setting the number of turns, current-carrying cross-sectional area of ​​the conductor tubes, and flow hole diameter of the conductor tubes. Furthermore, the first preheating conductor pipe, the second preheating conductor pipe, and the superheating conductor pipe are connected in series in that order. Water or steam is introduced from the inlet port provided in the first preheating conductor pipe, and superheated steam is discharged from the outlet port provided in the superheating conductor pipe via the second preheating conductor pipe, thus simplifying and miniaturizing the superheating steam generator. Here, since the temperature of the water or saturated steam flowing into the superheating conductor pipe is raised to a high temperature by the short-circuit section, it becomes possible to shorten the length of the superheating conductor pipe, which also enables miniaturization of the superheating steam generator. 【0009】 In order to enhance the effects of the present invention, it is desirable that the introduction port is provided at one axial end of the first preheating conductor tube and the outlet port is provided at the other axial end of the superheating conductor tube. In this configuration, since the inlet and outlet ports are located on opposite sides in the axial direction, the temperature influence of the water introduced from the inlet port on the superheated steam discharged from the outlet port can be reduced. Although one axial end of the superheated conductor tube is cooled by the water introduced from the inlet port, water heated by the short circuit or saturated steam is introduced to the other axial end of the superheated conductor tube, which allows for a reduction in superheating time and suppresses temperature changes of superheated steam due to changes in water volume. 【0010】 The axial end of the second preheating conductor tube and the axial end of the superheating conductor tube are connected, and it is preferable that the short-circuit portion is provided on the axial end side of the second preheating conductor tube. With this configuration, the water or saturated steam flowing through the second preheating conductor tube can be heated by the short-circuit just before it flows into one axial end of the superheating conductor tube, thus making the heating effect by the short-circuit more pronounced. 【0011】 Preferably, the superheated conductor tube comprises a first superheated conductor tube and a second superheated conductor tube arranged concentrically around the closed magnetic circuit core and wound spirally in opposite directions, and a connecting tube element that fluidly connects the axial ends of the first superheated conductor tube and the axial ends of the second superheated conductor tube and short-circuits them. With this configuration, there is no need to provide electrical connection members separately from the conducting pipe, and a short circuit can be formed by the structure of the conducting pipe itself. Furthermore, since the connecting pipe elements connect one axial end of each pipe element to the other axial end, the connection structure for forming a short circuit can be simplified. [Effects of the Invention] 【0012】 According to the present invention configured in this manner, it is possible to improve thermal efficiency by effectively utilizing the heat dissipation of the superheated conductor tube, and to reduce the effect of cooling the superheated conductor tube by water or steam introduced from the introduction port. [Brief explanation of the drawing] 【0013】 [Figure 1] This is a schematic cross-sectional view showing the configuration of a fluid heating device according to one embodiment of the present invention. [Figure 2] This figure schematically shows the radial arrangement of the fluid heating device of the same embodiment. [Figure 3] This figure shows the configuration of the closed magnetic circuit core in the same embodiment. [Figure 4] This is a schematic side view showing the configuration of the superheated conductor tubes (first superheated conductor tube and second superheated conductor tube) of the same embodiment. [Figure 5] It is a diagram showing the coil connection and the flow of fluid in the same embodiment. 【Embodiments for Carrying Out the Invention】 【0014】 An embodiment of a superheated steam generation device according to the present invention will be described below with reference to the drawings. 【0015】 <1. Device Configuration> The superheated steam generation device 100 according to the present embodiment generates superheated steam by heating water flowing through a conductor tube by causing heat generation through electromagnetic induction. Additionally, as the superheated steam generation device 100, for example, one that generates superheated steam by heating saturated steam generated externally may also be acceptable. 【0016】 Specifically, as shown in FIGS. 1 and 2, the superheated steam generation device 100 includes a closed magnetic circuit core 2, a primary coil to which an alternating voltage is applied, a spiral (coil-shaped) preheating conductor tube 3 disposed around the closed magnetic circuit core 2, a secondary coil through which an induced current flows, and a spiral (coil-shaped) superheating conductor tube 4 disposed around the closed magnetic circuit core 2. 【0017】 The closed magnetic circuit core 2, as particularly shown in FIG. 3, has two rectangular annular core elements 21 and 22, and is configured by combining the leg core portions 21a and 22a of the two core elements 21 and 22 so as to be in close contact with each other. The two core elements 21 and 22 have the same shape as each other, and each core element 21 and 22 is a wound core deformed into a rectangular ring shape, which is formed by laminating magnetic steel sheets so that the width decreases from the outside to the inside. Note that a directional electromagnetic steel sheet is used for the magnetic steel sheets. By using these core elements 21 and 22, the cross-sectional shape of the closed magnetic circuit core 2 becomes a multi-step shape. 【0018】 The preheating conductor tube 3 has a first preheating conductor tube 31 and a second preheating conductor tube 32 disposed concentrically around the closed magnetic circuit core 2. These first preheating conductor tube 31 and second preheating conductor tube 32 are wound in a spiral shape. 【0019】 The first and second preheating conductor tubes 31 and 32 are each wound in a single layer. The first preheating conductor tube 31 is arranged on the outermost side in the radial direction, and the second preheating conductor tube 32 is arranged on the innermost side in the radial direction. 【0020】 An introduction port P1 is provided at one axial end of the first preheating conductor tube 31, and the other axial end of the first preheating conductor tube 31 is connected to the other axial end of the second preheating conductor tube 32. Also, one axial end of the second preheating conductor tube 32 is connected to one axial end of the superheating conductor tube 4. 【0021】 Note that a flow rate adjustment valve 5 for adjusting the flow rate of water flowing into the first preheating conductor tube 31 is provided at or near the introduction port P1. Further, an AC power supply (not shown) for applying an AC voltage is connected to a power supply terminal 61 provided at one axial end of the first preheating conductor tube 31 and a power supply terminal 62 provided at one axial end of the second preheating conductor tube 32. 【0022】 And the first preheating conductor tube 31 is configured such that the wound portions of the conductor tube 31 do not short-circuit with each other. Note that the wound portion refers to one spiral turn portion. Specifically, the conductor tube 31 is wound with a gap such that the outer circumferential surfaces of the respective wound portions do not contact each other, so that the wound portions of the conductor tube 31 do not short-circuit with each other. In addition, the first preheating conductor tube 31 may be configured such that an insulating process such as winding an insulator (not shown) around its outer circumferential surface is performed so that the wound portions do not short-circuit with each other. 【0023】 Also, as shown in FIG. 1, the second preheating conductor tube 32 has a short-circuit portion 32X in which the wound portions of the conductor tube 32 are short-circuited with each other. Note that the wound portions of the second preheating conductor tube 32 other than the short-circuit portion 32X are configured not to short-circuit with each other. In addition, the wound portions of the second preheating conductor tube 32 other than the short-circuit portion 32X may be configured not to short-circuit with each other by performing an insulating process such as winding an insulator (not shown) around their outer circumferential surfaces. 【0024】 Specifically, the short-circuit section 32X is formed by short-circuiting the wound portion of the conductor pipe 32 in the spiral axial direction. Here, the short-circuit section 32X may be formed by connecting the wound portions of the conductor pipe 32 by welding or other joining, or by connecting an electrical connection member spanning the wound portions to each wound portion by welding or other joining. Furthermore, the short-circuit section 32X is formed by short-circuiting two or more wound portions. Furthermore, the short-circuit section 32X is provided on the axial end side of the second preheating conductor pipe 32. In this embodiment, the short-circuit section 32X is formed to include the outermost wound portion on the axial end side of the second preheating conductor pipe 32. 【0025】 As shown in Figure 4, the superheated conductor tube 4 includes a first superheated conductor tube 41 and a second superheated conductor tube 42 that are spirally wound in opposite directions, and first and second connecting tube elements 43 and 44 that fluidly connect the axial ends of the first superheated conductor tube 41 and the second superheated conductor tube 42 to each other and short-circuit them. The first superheated conductor tube 41 and the second superheated conductor tube 42 have a gap formed in the radial direction when viewed from the axial direction. 【0026】 The first superheated conductor tube 41 and the second superheated conductor tube 42 are positioned between the first preheated conductor tube 31 and the second preheated conductor tube 32. One axial end of the superheated conductor tube 4 is connected to one axial end of the second preheated conductor tube 32, and an outlet port P2 is provided at the other axial end of the superheated conductor tube 4. A temperature sensor 7 for controlling the temperature of superheated steam is provided at or near the outlet port P2. 【0027】 In this configuration, the conductor tubes 31, 32, 41, and 42 are arranged in the order of second preheating conductor tube 32, second superheating conductor tube 42, first superheating conductor tube 41, and first preheating conductor tube 31 from the radial inside, and are connected in series in the order of first preheating conductor tube 31, second preheating conductor tube 32, and superheating conductor tube 4. 【0028】 Furthermore, one axial end of the second preheating conductor pipe 32 is connected to the first connecting pipe element 43, and an outlet port P2 is provided in the second connecting pipe element 44. With this configuration, the fluid flowing in from the first connecting pipe element 43 branches off into the first superheating conductor pipe 41 and the second superheating conductor pipe 42 by the connecting pipe element 43, and the fluids that have flowed through the first superheating conductor pipe 41 and the second superheating conductor pipe 42 merge at the second connecting pipe element 44 and flow out from the outlet port P2. 【0029】 Furthermore, the superheated conductor tubes 4 connected in this manner are configured such that the first superheated conductor tube 41 and the second superheated conductor tube 42 are electrically connected in parallel by connecting tube elements 43 and 44. Then, the magnetic flux generated by the first and second preheated conductor tubes 31 and 32, which are primary coils, forms a closed circuit between the first superheated conductor tube 41 and the second superheated conductor tube 42, causing a short-circuit current to flow. In other words, a short-circuit current flows through the first superheated conductor tube 41 from one axial end to the other axial end, and a short-circuit current flows through the second superheated conductor tube 42 from the other axial end to the one axial end. 【0030】 Furthermore, in the superheated steam generator 100 of this embodiment, as shown in Figures 1 and 2, insulating material 8 is filled between the first preheating conductor pipe 31 and the first superheating conductor pipe 41, between the first superheating conductor pipe 41 and the second superheating conductor pipe 42, and between the second superheating conductor pipe 42 and the second preheating conductor pipe 32. This insulating material 8 is also filled in the gaps between the wound portions of each preheating conductor pipe 31, 32, and in the gaps between the wound portions of each superheating conductor pipe 41, 42. In this embodiment, a casing 9 is provided on the outer circumference of the first preheating conductor pipe 31, and insulating material 8 is provided between the first preheating conductor pipe 31 and the casing 9. In addition, insulating material 8 may be filled between the leg core portions 21a, 22a of the closed magnetic circuit core 2 and the second preheating conductor pipe 32. 【0031】 In the superheated steam generator 100 of this embodiment, when an AC voltage is applied from an AC power source to the power supply terminal 61 provided on the first preheating conductor pipe 31 and the power supply terminal 62 provided on the second preheating conductor pipe 32, an AC current flows through the first and second preheating conductor pipes 31 and 32, and magnetic flux flows through the closed magnetic circuit core 2. This magnetic flux causes a short-circuit current to flow through the first superheating conductor pipe 41, the second superheating conductor pipe 42 and the connecting pipe elements 43 and 44, causing the superheating conductor pipe 4 to generate Joule heat. In addition, the first and second preheating conductor pipes 31 and 32 generate Joule heat by being energized when an AC voltage is applied, and are also heated by heat transfer from the superheating conductor pipe 4. Furthermore, in the second preheating conductor pipe 32, a short-circuit current flows through the short-circuit section 32X, causing it to be heated to a higher temperature than the rest of the second preheating conductor pipe 32. 【0032】 As shown in Figure 5, the water introduced from the introduction port P1 of the first preheating conductor pipe 31 flows through the first and second preheating conductor pipes 31 and 32, where it is heated to high-temperature water or saturated steam. Furthermore, just before flowing into the superheating conductor pipe 4, it is further heated by the short-circuit section 32X of the second preheating conductor pipe 32. Subsequently, the high-temperature water or saturated steam that flows from the second preheating conductor pipe 32 into the superheating conductor pipe 4 is heated by the superheating conductor pipe 4 to become superheated steam, which is then discharged from the outlet port P2. 【0033】 <2. Effects of this embodiment> With the superheated steam generator 100 configured in this way, a first preheating conductor tube 31 and a second preheating conductor tube 32 are used as the primary coil, and a superheating conductor tube 4, which is a secondary coil, is provided between the first preheating conductor tube 31 and the second preheating conductor tube 32. As a result, the first preheating conductor tube 31 and the second preheating conductor tube 32 are heated by energizing them, and are also heated by utilizing the heat dissipation from the superheating conductor tube 4. This reduces the heat dissipation from the superheating conductor tube 4 to the outside of the device, thereby increasing thermal efficiency. 【0034】 In particular, in this embodiment, since the second preheating conductor tube 32 has a short-circuit section 32X that is short-circuited in the spiral axial direction, the preheated water or saturated steam flowing into the superheating conductor tube 4 can be further heated by Joule heating due to the short-circuit current. As a result, the effect of cooling the superheating conductor tube 4 by the water or steam introduced from the introduction port P1 is reduced, and the time required to heat the superheated steam to the desired temperature can be shortened. In addition, in response to temperature changes of superheated steam due to changes in the amount of water, the superheated steam can be heated to the desired temperature regardless of changes in the amount of water. 【0035】 Here, the first preheating conductor tube 31 and the second preheating conductor tube 32 that form the primary coil can have their heat generation ratio, heat transfer area ratio to the fluid, and fluid velocity ratio adjusted by setting the number of turns, current-carrying cross-sectional area of ​​the conductor tube, and flow hole diameter of the conductor tube. 【0036】 Furthermore, the first preheating conductor pipe 31, the second preheating conductor pipe 32, and the superheating conductor pipe 4 are connected in series in that order. Water or steam is introduced from the introduction port P1 provided in the first preheating conductor pipe 31, and superheated steam is discharged from the outlet port P2 provided in the superheating conductor pipe 4 via the second preheating conductor pipe 32 and the third preheating conductor pipe 33, thus simplifying and miniaturizing the superheating steam generator 100. Here, since the temperature of the water or saturated steam flowing into the superheating conductor pipe 4 is raised to a high temperature by the short-circuit section 32X, it is possible to shorten the length of the superheating conductor pipe 4, which also makes it possible to miniaturize the superheating steam generator 100. 【0037】 Furthermore, since the superheated conductor tube 4 is composed of a first superheated conductor tube 41, a second superheated conductor tube 42, and connecting tube elements 43 and 44, there is no need to provide electrical connection members separately from the conductor tube, and a short circuit can be formed by the configuration of the conductor tube itself. In addition, the connecting tube elements 43 and 44 are configured to connect one axial end of each superheated conductor tube 41 and 42 and the other axial ends of each, thus simplifying the connection structure for forming a short circuit. Moreover, since the superheated conductor tube 4 has a first superheated conductor tube 41 and a second superheated conductor tube 42, the contact area with the fluid (heat exchange area) can be increased, and the heating efficiency of the fluid can be improved. 【0038】 By making the superheated conductor tube 4 a secondary coil with multiple turns, the excitation current can be reduced and the leakage impedance can be decreased. This reduces the cross-sectional area of ​​the closed magnetic circuit core 2, thereby reducing the amount of core used, lowering iron loss, and improving thermal efficiency. In addition, by making the closed magnetic circuit core 2 a multi-stage shape, the surface area of ​​the core is increased, which enhances the cooling effect. 【0039】 <3. Modified Embodiments of the Invention> However, the present invention is not limited to the embodiments described above. For example, in the above embodiment, the first and second preheating conductor tubes 31 and 32 were each single-layer wound, but at least one of the first and second preheating conductor tubes 31 and 32 may be double-layer wound or more. 【0040】 Furthermore, in the above embodiment, the winding directions of the first superheated conductor tube 41 and the second superheated conductor tube 42 were opposite to each other, but the winding directions of the first superheated conductor tube 41 and the second superheated conductor tube 42 may be the same. In this case, one axial end of the first superheated conductor tube 41 and the other axial end of the second superheated conductor tube 42 are connected by a connecting pipe element 43, and the other axial end of the first superheated conductor tube 41 and one axial end of the second superheated conductor tube 42 are connected by a connecting pipe element 44. 【0041】 Furthermore, although the superheated conductor tube 4 in the above embodiment had a double-tube structure, it may also have four or more even-numbered tube elements. In this case, every two tube elements are connected by a connecting tube element. For example, it is conceivable to have a configuration in which multiple superheated conductor tubes 4 of the above embodiment are arranged concentrically. 【0042】 Furthermore, the above embodiment is applicable not only to single-phase AC systems but also to three-phase AC systems. 【0043】 Furthermore, it goes without saying that the present invention is not limited to the embodiments described above, and various modifications are possible without departing from its spirit. [Explanation of symbols] 【0044】 100...Superheated steam generator 2. Closed magnetic circuit core 21, 22... Iron core elements 21a, 22a... Leg core section 3. Preheating conductor tube 31. First preheating conductor tube 32...Second preheating conductor tube 32X...Short circuit 4. Superheated conductor tubes 41...First superheated conductor tube 42...Second superheated conductor tube 43, 44... Connecting pipe elements P1... Introduction port P2... Derivation port 8. Insulation

Claims

[Claim 1] A superheated steam generator that generates superheated steam by heating a conductive tube by electromagnetic induction and heating the water or steam flowing through the conductive tube, Closed magnetic circuit core and A primary coil to which an AC voltage is applied, comprising a spiral preheating conductor tube arranged around the closed magnetic circuit core, It comprises a secondary coil through which an induced current flows, and a spiral superheated conductor tube arranged around the closed magnetic circuit core, The preheating conductor tube comprises a first preheating conductor tube and a second preheating conductor tube arranged concentrically around the closed magnetic path core. The aforementioned conductor tubes are arranged in the order of the second preheating conductor tube, the superheating conductor tube, and the first preheating conductor tube from the radially inner side, and are connected in series in the order of the first preheating conductor tube, the second preheating conductor tube, and the superheating conductor tube. The second preheating conductor tube has a short-circuit section that is short-circuited in the spiral axial direction, Water or steam is introduced from an inlet port provided in the first preheating conductor tube, and superheated steam is discharged from an outlet port provided in the superheating conductor tube via the second preheating conductor tube. The introduction port is provided at one axial end of the first preheating conductor tube. The outlet port is provided at the other axial end of the superheated conductor tube. The axial end of the second preheating conductor tube and the axial end of the superheating conductor tube are connected, The short-circuit portion is a superheated steam generator provided on one axial end side of the second preheating conductor tube. [Claim 2] The superheated steam generator according to claim 1, wherein the superheated conductor tube comprises a first superheated conductor tube and a second superheated conductor tube arranged concentrically around the closed magnetic circuit core and wound spirally in opposite directions, and a connecting tube element that fluidly connects the axial ends of the first superheated conductor tube and the axial ends of the second superheated conductor tube and short-circuits them.