Power generation equipment and steam systems

Abstract

To suppress decline in power generation efficiency due to deviation of a pressing part of springs with respect to a heat exchanger.SOLUTION: A power generator 10 comprises: a thermoelectric conversion module 1 which has a first surface 11 and a second surface 12 opposite to each other; a heating heat exchanger 3 which contacts the first surface 11 and heats the first surface 11; a cooling heat exchanger 5 which contacts the second surface 12 and cools the second surface 12; and a plurality of springs 8 which have a first plate 81 parallel to the first surface 11 and the second surface 12, a second plate 82 extending obliquely with respect to the first plate 81, and a bent part 83 connecting the first plate 81 and the second plate 82 in an approximate V-shape, and are elastically deformed so that a free end of the first plate 81 and a free end of the second plate 82 approach mutually or separated from each other, and in which the free end of the second plate 82 presses the cooling heat exchanger 5. The plurality of springs 8 are arranged so as to be aligned in a predetermined direction within a surface parallel to the first surface 11 and the second surface 12, and so as to make directions of the bent part 83 of the two adjacent springs 8 differ from each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The technology of the present disclosure relates to a power generation device and a steam system including the same.

Background Art

[0002] Conventionally, a power generation device that performs thermoelectric power generation using a thermoelectric conversion element has been known. For example, in the power generation device disclosed in Patent Document 1, a thermoelectric conversion element is provided between an inner cylinder through which exhaust gas flows and a heat radiation fin. In this power generation device, the high-temperature surface of the thermoelectric conversion element is heated by the exhaust gas, and the low-temperature surface of the thermoelectric conversion element is cooled by the heat radiation fin. As a result, a temperature difference occurs between the high-temperature surface and the low-temperature surface, and thermoelectric power generation is performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power generation device as described above, in order to improve the power generation efficiency, it is important to increase the degree of adhesion between the heating heat exchanger and the cooling heat exchanger and the thermoelectric conversion module. Therefore, it is conceivable to increase the above-mentioned degree of adhesion by pressing one of the heating heat exchanger and the cooling heat exchanger against the other by a leaf spring whose cross section is bent in a V shape. However, in that case, the pressing portion by the spring may be biased in the heat exchanger on the side to be pressed, and therefore, there is a risk that the power generation efficiency may decrease.

[0005] The technology of the present disclosure has been made in view of such circumstances, and an object thereof is to suppress a decrease in power generation efficiency caused by a bias of a pressing portion by a spring against a heat exchanger.

Means for Solving the Problems

[0006] The power generation device of this disclosure comprises a thermoelectric conversion module, a heating heat exchanger, a cooling heat exchanger, and a plurality of springs. The thermoelectric conversion module has a first surface and a second surface facing opposite directions, and generates thermoelectric power according to the temperature difference between the first surface and the second surface. The heating heat exchanger is in contact with the first surface and heats the first surface. The cooling heat exchanger is in contact with the second surface and cools the second surface. The plurality of springs have a first plate parallel to the first and second surfaces, a second plate extending diagonally with respect to the first plate, and a bent portion connecting the first plate and the second plate in a substantially V-shape, and elastically deforms so that the free end of the first plate and the free end of the second plate move closer together or further apart, and the free end of the second plate presses one of the heating heat exchanger and the cooling heat exchanger toward the other. Furthermore, the plurality of springs are arranged in a predetermined direction within a plane parallel to the first and second surfaces, and are positioned such that the direction in which the bent portions of two adjacent springs face is different from that of the other two springs in the predetermined direction.

[0007] The steam system of this disclosure comprises a steam-using device to which steam is supplied and which uses the supplied steam, and the aforementioned power generation device, wherein a portion of the steam before it is supplied to the steam-using device is supplied to the heating heat exchanger. [Effects of the Invention]

[0008] According to the above-mentioned power generation device, it is possible to suppress the decrease in power generation efficiency caused by uneven pressure on the heat exchanger by the spring.

[0009] According to the steam system described above, it is possible to suppress the decrease in power generation efficiency caused by uneven pressure distribution on the heat exchanger by the spring. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is an exploded perspective view of the power generation device. [Figure 2] Figure 2 is a front view of the power generation device. [Figure 3] Figure 3 is a side view of the power generation device. [Figure 4] Figure 4 is a perspective view of the assembled cooling heat exchanger, presser, and base, viewed from a diagonal downward angle. [Figure 5] Figure 5 is a side view of the assembled thermoelectric conversion module, cooling heat exchanger, and presser. [Figure 6] Figure 6 is a front view of the assembled thermoelectric conversion module, cooling heat exchanger, and presser. [Figure 7] Figure 7 is a piping diagram showing the schematic configuration of the drain recovery system. [Figure 8] Figure 8 is an exploded perspective view of a modified thermoelectric conversion module, cooling heat exchanger, and presser. [Figure 9] Figure 9 is a front view showing the assembled state of the thermoelectric conversion module, cooling heat exchanger, and presser according to the modified example. [Modes for carrying out the invention]

[0011] The following exemplary embodiments will be described in detail with reference to the drawings.

[0012] Figure 1 is an exploded perspective view of the power generation device 10. Figure 2 is a front view of the power generation device 10. Figure 3 is a side view of the power generation device 10. Figure 4 is a perspective view of the assembled cooling heat exchanger 5, presser 7, and base 9, viewed from diagonally below.

[0013] The power generation device 10 is a thermoelectric power generation device that generates electricity. The power generation device 10 comprises a thermoelectric conversion module 1 that performs thermoelectric power generation by converting thermal energy into electrical energy, a heating heat exchanger 3 that heats the thermoelectric conversion module 1, and a cooling heat exchanger 5 that cools the thermoelectric conversion module 1. The thermoelectric conversion module 1 is positioned between the heating heat exchanger 3 and the cooling heat exchanger 5. In the power generation device 10, the heating heat exchanger 3 and the cooling heat exchanger 5 generate a temperature difference in the thermoelectric conversion module 1, and the thermoelectric conversion module 1 generates electricity according to the temperature difference.

[0014] The power generation device 10 further includes a presser 7 that presses one of the heating heat exchanger 3 and the cooling heat exchanger 5 toward the other. In this example, the heating heat exchanger 3 is a fixed heat exchanger fixedly installed, and the cooling heat exchanger 5 is a movable heat exchanger movably installed. That is, the presser 7 presses the cooling heat exchanger 5 toward the heating heat exchanger 3. A thermoelectric conversion module 1 is disposed between the heating heat exchanger 3 and the cooling heat exchanger 5. Therefore, the contact between the cooling heat exchanger 5 and the thermoelectric conversion module 1 is maintained, and further, the contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 is maintained.

[0015] The power generation device 10 further includes a positioner 2 that positions the thermoelectric conversion module 1. The positioner 2 positions the thermoelectric conversion module 1 between the heating heat exchanger 3 and the cooling heat exchanger 5. The power generation device 10 further includes a supporter 25 that supports the positioner 2.

[0016] The power generation device 10 further includes a base 9 that supports the cooling heat exchanger 5 and the like. The base 9 is attached to the heating heat exchanger 3.

[0017] In the power generation device 10, the heating heat exchanger 3, the thermoelectric conversion module 1, the cooling heat exchanger 5, the presser 7, and the base 9 are stacked in this order. The direction in which the heating heat exchanger 3 and the cooling heat exchanger 5 and the like are stacked is referred to as the "stacking direction". In this example, the stacking direction is the vertical direction. The heating heat exchanger 3 is disposed below, and the base 9 is disposed above. That is, the heating heat exchanger 3 is disposed below the thermoelectric conversion module 1, and the cooling heat exchanger 5 is disposed above the thermoelectric conversion module 1. [[ID=1']]

[0018] =Thermoelectric Conversion Module= The thermoelectric conversion module 1 includes a plurality of thermoelectric conversion elements. A thermoelectric conversion element is a device that converts thermal energy into electrical energy and is also called a Seebeck element. A thermoelectric conversion element is formed by a pair of a p-type semiconductor and an n-type semiconductor. In the thermoelectric conversion module 1, a plurality of thermoelectric conversion elements are thermally arranged in parallel, and a plurality of thermoelectric conversion elements are electrically connected in series via electrodes formed at both ends of the plurality of thermoelectric conversion elements.

[0019] As shown in FIG. 1, the thermoelectric conversion module 1 is formed in a substantially flat plate shape, more specifically, in a substantially flat plate shape that is substantially square in plan view. The thermoelectric conversion module 1 has a first surface 11 and a second surface 12 that face each other in the thickness direction. A plurality of thermoelectric conversion elements are two-dimensionally arranged such that the electrodes on the high-temperature side face the first surface 11 and the electrodes on the low-temperature side face the second surface 12. The thermoelectric conversion module 1 performs thermoelectric power generation according to the temperature difference between the first surface 11 and the second surface 12. The first surface 11 is a high-temperature surface, and the second surface 12 is a low-temperature surface.

[0020] In this example, the power generation device 10 includes a plurality (specifically, four) of thermoelectric conversion modules 1. The plurality of thermoelectric conversion modules 1 are arranged in a flat plate shape as a whole. In this example, the plurality of thermoelectric conversion modules 1 are arranged in a row in a direction substantially orthogonal to the stacking direction with a gap therebetween. All of the first surfaces 11 of the plurality of thermoelectric conversion modules 1 face the same direction, specifically, downward. All of the second surfaces 12 of the plurality of thermoelectric conversion modules 1 face the same direction, specifically, upward.

[0021] Hereinafter, for the sake of convenience of explanation, on the premise that the stacking direction coincides with the vertical direction, the arrangement direction of the thermoelectric conversion module 1 is referred to as the "left-right direction". Also, the direction orthogonal to both the vertical direction and the left-right direction is referred to as the "front-back direction".

[0022] =Heating heat exchanger= The heating heat exchanger 3 is in contact with the first surface 11 of the thermoelectric conversion module 1 and heats the first surface 11. Steam is supplied to the heating heat exchanger 3 as a heat source. The heating heat exchanger 3 performs heat exchange between the steam and the first surface 11. In other words, the heating heat exchanger 3 heats the first surface 11 with steam.

[0023] Specifically, the heating heat exchanger 3 has a main body 30, an inlet port 31, and an outlet port 32. The main body 30 is formed in a container shape. The main body 30 has a cylindrical side circumferential wall 33 extending in a predetermined longitudinal direction, a first end wall 34 that closes one end of the side circumferential wall 33, and a second end wall 35 that closes the other end of the side circumferential wall 33. A substantially planar heating surface 36 is formed on a part of the side circumferential wall 33, as shown in Figure 1. The heating surface 36 faces the thermoelectric conversion module 1 in the stacking direction. Four heating surfaces 36 are formed on the main body 30 corresponding to the thermoelectric conversion module 1. The inlet port 31 is provided on the first end wall 34. The outlet port 32 is provided on the second end wall 35. The main body 30 is an example of a heating main body.

[0024] The heating heat exchanger 3 is positioned such that its heating surface 36 is in contact with the first surface 11 of the thermoelectric conversion module 1. More specifically, the heating heat exchanger 3 is positioned so that its heating surface 36 faces upward and its longitudinal direction coincides with the arrangement direction of the thermoelectric conversion module 1.

[0025] Steam flows into the main body 30 through the inlet port 31. The steam that flows into the main body 30 condenses into drain water through heat exchange with the thermoelectric conversion module 1. The drain water inside the main body 30 flows out through the outlet port 32. More specifically, the steam in the main body 30 radiates heat to the first surface 11 of the thermoelectric conversion module 1 via the heating surface 36 of the side wall 33. This heats the first surface 11. The steam inside the main body 30 condenses into drain water through heat exchange with the first surface 11. The drain water temporarily remains inside the main body 30 and finally flows out through the outlet port 32.

[0026] The heating heat exchanger 3 has a mounting base 4 to which the base 9 is attached. The mounting base 4 is provided on the main body 30. In this example, the mounting base 4 is a flat plate oriented substantially perpendicular to the stacking direction and is formed in a substantially rectangular frame shape in plan view. The mounting base 4 is arranged to surround the outer periphery of the main body 30.

[0027] The mounting base 4 is provided with four stands 48. The four stands 48 are positioned at the four corners of the mounting base 4. Each stand 48 extends in a stacking direction from the mounting base 4 toward the opposite side of the heating heat exchanger 3. The power generation device 10 is placed on the floor or the like via the four stands 48.

[0028] =Cooling heat exchanger= The cooling heat exchanger 5 is in contact with the second surface 12 of the thermoelectric conversion module 1 and cools the second surface 12. Cooling water is supplied to the cooling heat exchanger 5 as a cooling source. The cooling heat exchanger 5 performs heat exchange between the cooling water and the second surface 12. In other words, the cooling heat exchanger 5 cools the second surface 12 with the cooling water. Cooling water is an example of a coolant.

[0029] Specifically, the cooling heat exchanger 5 has a main body 50, an inlet port 51, and an outlet port 52. The main body 50 is formed in a container shape. More specifically, the main body 50 is formed in a substantially rectangular tubular shape, that is, a substantially rectangular parallelepiped shape, extending in a predetermined longitudinal direction. The main body 50 has a first wall 53, a second wall 54, a third wall 55, a fourth wall 56, a fifth wall 57, and a sixth wall 58. The first wall 53 and the second wall 54 are formed in a substantially rectangular shape and face each other. The third wall 55 is connected to one long side of the first wall 53 and one long side of the second wall 54, respectively. The fifth wall 57 faces the third wall 55 and is connected to the other long side of the first wall 53 and the other long side of the second wall 54, respectively. The fourth wall 56 is connected to one short side of the first wall 53 and one short side of the second wall 54, respectively. The sixth wall 58 faces the fourth wall 56 and is connected to the other short side of the first wall 53 and the other short side of the second wall 54, respectively. A substantially planar cooling surface 59 is formed on the first wall 53. The main body 50 is an example of a cooling body.

[0030] The inlet port 51 is located at one end of the main body 50 in the longitudinal direction, and the outlet port 52 is located at the other end of the main body 50 in the longitudinal direction. More specifically, the inlet port 51 is located at the end of the third wall 55 closest to the sixth wall 58. The outlet port 52 is located at the end of the third wall 55 closest to the fourth wall 56.

[0031] The cooling heat exchanger 5 is positioned such that its cooling surface 59 is in contact with the second surface 12 of the thermoelectric conversion module 1. More specifically, the cooling heat exchanger 5 is positioned so that its cooling surface 59 faces downward and its longitudinal direction coincides with the arrangement direction of the thermoelectric conversion module 1.

[0032] Cooling water flows into the main body 50 from the inlet port 51. The cooling water that flows into the main body 50 circulates inside the main body 50 and flows out from the outlet port 52. As the cooling water circulates inside the main body 50, it exchanges heat with the thermoelectric conversion module 1. More specifically, the cooling water inside the main body 50 absorbs heat from the second surface 12 of the thermoelectric conversion module 1 via the cooling surface 59 of the first wall 53. This cools the second surface 12.

[0033] =Positioning device= The positioning device 2 determines the position of the thermoelectric conversion module 1 in the in-plane direction of the first surface 11 or the second surface 12 between the heating heat exchanger 3 and the cooling heat exchanger 5. As shown in Figure 1, the positioning device 2 has a frame-shaped frame 20 and a mounting portion 21 connected to the frame 20. The positioning device 2 has the function of determining the position of multiple thermoelectric conversion modules 1 and the function of insulating the multiple thermoelectric conversion modules 1 from one another. In other words, the positioning device 2 positions the thermoelectric conversion modules 1 so that they are in proper contact with the heating surface 36 and the cooling surface 59 while insulating each pair of adjacent thermoelectric conversion modules 1.

[0034] The frame 20 is positioned between the heating heat exchanger 3 and the cooling heat exchanger 5. The thickness of the frame 20 (i.e., the dimension in the stacking direction) is thinner than the thickness of the thermoelectric conversion module 1 (i.e., the dimension in the stacking direction). Since the gap between the heating heat exchanger 3 and the cooling heat exchanger 5 is determined by the thickness of the thermoelectric conversion module 1, the thickness of the frame 20 is thinner than the distance between the heating heat exchanger 3 and the cooling heat exchanger 5.

[0035] The frame 20 has a shape that at least partially conforms to the outer shape of the thermoelectric conversion module 1 in a plane substantially parallel to the first surface 11 (or second surface 12). The frame 20 has spacers 23 positioned between each pair of adjacent thermoelectric conversion modules 1 in the arrangement direction. The spacers 23 isolate each pair of thermoelectric conversion modules 1 from one another. In this example, since there are four thermoelectric conversion modules 1, the frame 20 has three spacers 23. The spacers 23 are formed of thermal insulation material. In this example, the entire positioner 2 is formed of thermal insulation material.

[0036] The positioning device 2 has two mounting parts 21. The two mounting parts 21 protrude from the frame 20 on both sides in the direction of arrangement. That is, the two mounting parts 21 protrude in the direction of arrangement from the gap between the heating heat exchanger 3 and the cooling heat exchanger 5. The mounting parts 21 are attached to the support 25.

[0037] More specifically, the support 25 has a shaft 25a extending in a direction intersecting the first surface 11. In this example, the support 25 has two shafts 25a. The two shafts 25a are located on the heating heat exchanger 3. More specifically, the two shafts 25a are located on the outside of the main body 30 in the longitudinal direction of the main body 30. The shafts 25a are provided on the mounting base 4. The shafts 25a extend from the mounting base 4 toward the cooling heat exchanger 5 in a direction substantially perpendicular to the heating surface 36, that is, in a direction substantially perpendicular to the first surface 11. The tip of the shaft 25a is a free end.

[0038] The mounting portion 21 is attached to the shaft 25a. Specifically, the mounting portion 21 has a through hole 21a through which the shaft 25a is inserted. The positioning device 2 is placed on the heating heat exchanger 3 so that the shaft 25a is inserted through the through hole 21a. The frame 20 is positioned to partially border the four heating surfaces 36. The thermoelectric conversion module 1 is placed in the space partitioned by the frame 20. As a result, the thermoelectric conversion module 1 is positioned on the heating surface 36.

[0039] =Base= The base 9 is attached to the heating heat exchanger 3. The base 9 and the heating heat exchanger 3 support the thermoelectric conversion module 1, the cooling heat exchanger 5, and the presser 7. In other words, the thermoelectric conversion module 1, the cooling heat exchanger 5, and the presser 7 are positioned between the base 9 and the heating heat exchanger 3. The base 9 is generally formed in a plate shape. The base 9 has a main body 90 and bent portions 91 provided at the edges of the main body 90. The main body 90 is formed in a roughly rectangular shape in plan view. The main body 90 extends in a plane that is roughly perpendicular to the stacking direction. Two bent portions 91 are provided at both ends of the main body 90 corresponding to the long sides of the rectangle. The two bent portions 91 are bent in the same direction from the main body 90 in the stacking direction. Each bent portion 91 is bent so as to be roughly perpendicular to the main body 90. The main body 90 is provided with two handles 92. The handles 92 are located at both ends of the main body 90 corresponding to the short sides of the rectangle.

[0040] The base 9 is positioned such that the longitudinal direction of the main body 90 coincides with the longitudinal direction of the heating heat exchanger 3 and the main body 90 is substantially parallel to the heating surface 36 of the heating heat exchanger 3. The base 9 is attached to the heating heat exchanger 3 by four screws 93. Through holes are formed in the four corners of the main body 90 through which the screws 93 are inserted. Four screw holes are formed in the mounting base 4 of the heating heat exchanger 3 in the parts opposite to the four through holes. Four spacers 94 are provided between the base 9 and the mounting base 4. The spacers 94 are positioned so as to extend in the stacking direction between the base 9 and the mounting base 4. The spacers 94 are formed in a cylindrical shape through which the screws 93 are inserted.

[0041] Each screw 93 is inserted through a through hole in the main body 90 and a spacer 94, and screwed into a screw hole in the mounting base 4. The base 9 is attached to the heating heat exchanger 3 by tightening the four screws 93. At this time, the distance between the main body 90 of the base 9 and the mounting base 4 of the heating heat exchanger 3 is maintained by the length of the spacer 94.

[0042] The base 9 has guides 95 that support the presser 7. The base 9 has two guides 95. The guides 95 are provided on the main body 90. Guides 95 are positioned at each of the two end edges corresponding to the long sides of the rectangle of the main body 90. The position of one guide 95 in the longitudinal direction of the main body 90 is different from that of the other guide 95. The guides 95 extend in the stacking direction from the main body 90 toward the heating heat exchanger 3. The guides 95 are formed in a substantially cylindrical shape. The tip of the guide 95 is a free end.

[0043] =Pressure device= The presser 7 includes a contactor 71 that contacts the cooling heat exchanger 5, and a spring 8 that elastically biases the contactor 71 toward the cooling heat exchanger 5. The presser 7 presses the cooling heat exchanger 5 toward the heating heat exchanger 3 by the elastic force of the spring 8. The contactor 71 and the spring 8 are positioned between the cooling heat exchanger 5 and the base 9. The contactor 71 is positioned to contact the cooling heat exchanger 5. The spring 8 is positioned between the contactor 71 and the base 9 in a compressed and deformed state.

[0044] More specifically, the contactor 71 is formed in a flat plate shape that extends in a plane substantially perpendicular to the stacking direction (i.e., in a plane parallel to the first and second surfaces). The contactor 71 is in contact with the cooling heat exchanger 5. More specifically, the contactor 71 is in contact with the second wall 54 of the cooling heat exchanger 5. As shown in Figure 1, the contactor 71 has two through holes 73 through which the guide 95 is inserted. The contactor 71 is supported by the guide 95 so as to be movable in the stacking direction relative to the base 9, but not so movable in a direction substantially perpendicular to the stacking direction, i.e., in the in-plane direction of the second surface 12.

[0045] Figure 5 is a side view of the assembled thermoelectric conversion module 1, cooling heat exchanger 5, and presser 7. Figure 6 is a front view of the assembled thermoelectric conversion module 1, cooling heat exchanger 5, and presser 7.

[0046] Spring 8 is a so-called leaf spring. More specifically, spring 8 has a first plate 81, a second plate 82, and a bent portion 83 that connects the first plate 81 and the second plate 82 to each other. The first plate 81 is parallel to the first surface 11 and the second surface 12, and the second plate 82 extends diagonally to the first plate 81. The bent portion 83 connects the first plate 81 and the second plate 82 in a roughly V-shape. In this example, the first plate 81 and the second plate 82 are formed in a rectangular shape with their longitudinal direction. The edge of the first plate 81 opposite to the bent portion 83 and the edge of the second plate 82 opposite to the bent portion 83 are free ends. The distance between the first plate 81 and the second plate 82 widens towards the free ends of the first plate 81 and the second plate 82. In other words, spring 8 is formed in a shape that is bent in a roughly V-shape in cross-section. The spring 8 as a whole undergoes elastic deformation such that the free end of the first plate 81 and the free end of the second plate 82 move closer together or further apart. That is, the first plate 81, the second plate 82, and the bent portion 83 each undergo elastic deformation.

[0047] The spring 8 is attached to the base 9. Specifically, the first plate 81 is screwed to the base 9 while superimposed on the main body 90 of the base 9. As a result, the second plate 82 extends diagonally from the base 9 toward the contactor 71 with respect to the stacking direction, as shown in Figure 5. The free end of the second plate 82 contacts the contactor 71. The free end of the second plate 82 presses against the contactor 71.

[0048] In other words, the free end of the second plate 82 presses against the cooling heat exchanger 5, which is in contact with the contactor 71, via the contactor 71. More specifically, the free end of the second plate 82 presses against the outer surface of the second wall 54 of the cooling heat exchanger 5 via the contactor 71. In the body 50 of the cooling heat exchanger 5, the outer surface of the second wall 54 is a pressing surface formed in a rectangular shape that extends in a predetermined longitudinal direction parallel to the first surface 11 and the second surface 12 (in this example, the direction that coincides with the arrangement direction). In other words, in the cooling heat exchanger 5, the cooling surface 59 of the first wall 53, which is the surface facing the opposite direction from the pressing surface in the body 50, is in contact with the second surface 12 of the thermoelectric conversion module 1.

[0049] The presser 7 has a plurality of springs 8, and in this example, it has two springs 8. The plurality of springs 8 are arranged in a predetermined direction in a plane parallel to the first surface 11 and the second surface 12, and are arranged such that the directions of the bent portions 83 of two adjacent springs 8 in the predetermined direction are different from each other. Specifically, the predetermined direction coincides with the longitudinal direction (i.e., the arrangement direction) of the second wall 54 of the main body 50. The bent portions 83 of two adjacent springs 8 in the predetermined direction are facing opposite directions in the short direction of the second wall 54. Here, the direction in which the bent portion 83 is facing is the direction in which the outwardly protruding side of the bent portion 83 is facing.

[0050] Specifically, the two springs 8 are aligned in the direction of arrangement (i.e., the longitudinal direction of the main body 90). Each spring 8 is positioned such that the free end of the first plate 81 and the bent portion 83 are aligned in the front-to-back direction (i.e., the short-to-back direction of the main body 90). The front-to-back positions of the free end of the first plate 81 and the bent portion 83 are reversed in the two springs 8. That is, the bent portion 83 of one of the two springs 8 faces forward, and the bent portion 83 of the other faces backward. To put it another way, the free end of the first plate 81 of one of the two springs 8 faces backward, and the free end of the first plate 81 of the other spring 8 faces forward.

[0051] By arranging the two springs 8 in this way, as shown in Figure 5, the free end of the second plate 82 of one spring 8 contacts the portion of the contactor 71 that corresponds to the rear edge of the second wall 54, and the free end of the second plate 82 of the other spring 8 contacts the portion of the contactor 71 that corresponds to the front edge of the second wall 54. Therefore, the pressing force from the springs 8 acts evenly on both the front and rear sides in the longitudinal direction of the main body 50. In other words, the portion of the contactor 71 that is pressed by the springs 8 can be widely distributed in the arrangement direction and the front-rear direction. This increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1.

[0052] The presser 7 has stoppers 74 that restrict the displacement of the cooling heat exchanger 5. Specifically, the presser 7 has four stoppers 74, as shown in Figure 4. The stoppers 74 are provided on the contactor 71. The stoppers 74 are provided on the surface of the contactor 71 that faces the cooling heat exchanger 5. The stoppers 74 are positioned adjacent to the cooling heat exchanger 5 in a direction substantially parallel to the second surface 12. The four stoppers 74 are positioned around the cooling heat exchanger 5, that is, on all four sides of the cooling heat exchanger 5. Specifically, each of the four stoppers 74 is positioned opposite the third wall 55, fourth wall 56, fifth wall 57, and sixth wall 58 of the cooling heat exchanger 5. The four stoppers 74 are in contact with each of the third wall 55, fourth wall 56, fifth wall 57, and sixth wall 58 of the cooling heat exchanger 5. As a result, the stopper 74 restricts the displacement of the cooling heat exchanger 5 in the in-plane direction of the second surface 12.

[0053] More specifically, the stopper 74 is formed by bending sheet metal. The stopper 74 has a first plate 74a that is attached to the contactor 71 and a second plate 74b that contacts the cooling heat exchanger 5. The second plate 74b is bent at approximately a right angle from the first plate 74a. The first plate 74a is attached to the contactor 71 by screws. The second plate 74b extends approximately parallel to and contacts the corresponding wall among the third wall 55, fourth wall 56, fifth wall 57 and sixth wall 58.

[0054] The contactor 71 is positioned on the cooling heat exchanger 5 with the stopper 74 facing toward the cooling heat exchanger 5. The cooling heat exchanger 5 is surrounded by four stoppers 74. The spring 8 is attached to the base 9. The base 9 is attached to the heating heat exchanger 3 so that the spring 8 is in contact with the contactor 71. At this time, the guide 95 of the base 9 is inserted through the through hole 73 of the contactor 71. The spring 8 is compressed and deformed by the contactor 71 and the base 9 so that the free end of the first plate 81 and the free end of the second plate 82 are brought closer together. The spring 8 exerts an elastic force that pushes the contactor 71 away from the base 9 in the stacking direction. The contactor 71 pushes the cooling heat exchanger 5 toward the heating heat exchanger 3 in the stacking direction due to the elastic force of the spring 8.

[0055] The pressing of the cooling heat exchanger 5 by the presser 7 ensures contact between the thermoelectric conversion module 1 and the cooling heat exchanger 5, as well as contact between the thermoelectric conversion module 1 and the heating heat exchanger 3. This improves the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 5.

[0056] At this time, the contactor 71 is immobile relative to the base 9 in the in-plane direction of the second surface 12 by the support of the guide 95. The cooling heat exchanger 5 is immobile relative to the contactor 71 in the in-plane direction of the second surface 12 by the stopper 74. The base 9 is fixed to the heating heat exchanger 3. In other words, with respect to displacement in the in-plane direction of the second surface 12, the cooling heat exchanger 5 is restricted by the stopper 74 of the contactor 71, the contactor 71 is restricted by the guide 95 of the base 9, and the base 9 is restricted by the heating heat exchanger 3. As a result, the cooling heat exchanger 5 is immobile relative to the heating heat exchanger 3 in the in-plane direction of the second surface 12. This reduces the misalignment of the cooling heat exchanger 5 relative to the thermoelectric conversion module 1 in the in-plane direction of the second surface 12.

[0057] =Assembly of the power generation device= Next, the assembly of the power generation device 10 will be explained. First, the heating heat exchanger 3 is placed on the floor or the like via the stand 48. A shaft 25a is attached to the heating heat exchanger 3.

[0058] Next, the positioner 2 is placed on the heating heat exchanger 3. The positioner 2 is positioned on the heating heat exchanger 3 such that the shaft 25a is inserted through the through hole 21a. The positioner 2 surrounds the four heating surfaces 36, exposing the heating surfaces 36. The thermoelectric conversion module 1 is then placed on the heating surfaces 36 with its first surface 11 facing the heating surfaces 36. Furthermore, the cooling heat exchanger 5 is placed on top of the thermoelectric conversion module 1 such that its cooling surface 59 is in contact with the second surface 12 of the thermoelectric conversion module 1.

[0059] Next, the contactor 71 of the presser 7 is placed on the cooling heat exchanger 5. The spring 8 is attached to the base 9. The base 9 is attached to the heating heat exchanger 3 so that the spring 8 is in contact with the contactor 71. At this time, the guide 95 attached to the base 9 is inserted through the through hole 73 of the contactor 71. The base 9 is attached to the heating heat exchanger 3 by screws 93 via spacers 94. The spacers 94 determine the distance between the base 9 and the heating heat exchanger 3. As a result, the spring 8 is elastically deformed, and the elastic force of the spring 8 causes the contactor 71 to press the cooling heat exchanger 5 toward the heating heat exchanger 3.

[0060] By attaching the base 9 to the heating heat exchanger 3 in this manner, the presser 7 presses the cooling heat exchanger 5 toward the heating heat exchanger 3, causing the heating heat exchanger 3 and the cooling heat exchanger 5 to sandwich the thermoelectric conversion module 1. This ensures contact between the thermoelectric conversion module 1 and the heating heat exchanger 3, and between the thermoelectric conversion module 1 and the cooling heat exchanger 5.

[0061] =Operation of the power generation device= Next, the operation of the power generation device 10 will be explained.

[0062] In the heating heat exchanger 3, steam is supplied to the main body 30 from the inlet port 31. The steam remains inside the main body 30. Meanwhile, in the cooling heat exchanger 5, cooling water is supplied to the main body 50 from the inlet port 51. The cooling water circulates inside the main body 50.

[0063] The first surface 11 of the thermoelectric conversion module 1 is in contact with the heating surface 36 of the heating heat exchanger 3, and is therefore heated by the steam inside the main body 30. On the other hand, the second surface 12 of the thermoelectric conversion module 1 is in contact with the cooling surface 59 of the cooling heat exchanger 5, and is therefore cooled by the cooling water inside the main body 50. As a result, a temperature difference is created between the first surface 11 and the second surface 12 of the thermoelectric conversion module 1, and the thermoelectric conversion module 1 generates electricity according to this temperature difference. In this way, the power generation device 10 generates electricity by utilizing the thermal energy of steam.

[0064] Here, the cooling heat exchanger 5 is pressed toward the heating heat exchanger 3 via the contactor 71 by two springs 8. In the contactor 71, the parts pressed by the two springs 8 are widely distributed in the alignment direction and the front-to-back direction, so the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1 is increased. As a result, the decrease in power generation efficiency caused by uneven pressure distribution on the heat exchangers by the springs 8 is suppressed.

[0065] Furthermore, in the heating heat exchanger 3, the steam flowing into the main body 30 condenses upon contact with the first surface 11 of the thermoelectric conversion module 1 via the heating surface 36. The condensate temporarily accumulates within the main body 30 and eventually flows out through the outlet port 32. Here, since the heating surface 36 is located at the top of the main body 30, the condensate within the main body 30 accumulates at the bottom of the main body 30, that is, in a part relatively far from the heating surface 36. Therefore, the heating of the first surface 11 via the heating surface 36 is not hindered by the condensate. In this way, by positioning the heating heat exchanger 3 below the thermoelectric conversion module 1, the condensate can be accumulated in a part far from the heating surface 36. This improves the heating efficiency of the heating heat exchanger 3.

[0066] On the other hand, in the cooling heat exchanger 5, the cooling water flowing into the main body 50 absorbs heat from the second surface 12 of the thermoelectric conversion module 1 via the cooling surface 59. The cooling water is heated as it flows through the main body 50 and flows out from the outlet port 52. Here, since the cooling surface 59 is located at the bottom of the main body 50, the cooling water heated by the second surface 12 circulates towards the top of the main body 50. As a result, relatively low-temperature cooling water is distributed near the cooling surface 59, and relatively high-temperature cooling water is distributed further away from the cooling surface 59. In this way, by positioning the cooling heat exchanger 5 above the thermoelectric conversion module 1, the cooling efficiency of the cooling heat exchanger 5 is improved.

[0067] Furthermore, in the heating heat exchanger 3, the main body 30 may expand due to the heat and pressure of the steam. Here, the thermoelectric conversion module 1 is supported by being sandwiched between the heating heat exchanger 3 and the cooling heat exchanger 5, and the cooling heat exchanger 5 is supported so as to be elastically movable in the stacking direction. Specifically, the cooling heat exchanger 5 is elastically pressed toward the heating heat exchanger 3 in the stacking direction by the presser 7, and the contactor 71 of the presser 7 is supported by the guide 95 so as to be movable in the stacking direction relative to the base 9 (and consequently relative to the heating heat exchanger 3). Therefore, in accordance with the expansion deformation of the main body 30 of the heating heat exchanger 3, the thermoelectric conversion module 1 and the cooling heat exchanger 5 can be displaced in the stacking direction. In other words, the spring 8 of the presser 7 absorbs the expansion deformation of the main body 30 of the heating heat exchanger 3. As a result, damage to the thermoelectric conversion module 1 is reduced, and contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 5 is properly maintained. Here, the positioner 2 is supported by the support 25 by the insertion of a shaft 25a into the through hole 21a, so the positioner 2 is supported to be movable in the longitudinal direction of the shaft 25a, i.e., in the stacking direction. The positioner 2 can also be displaced in the stacking direction together with the thermoelectric conversion module 1 and the cooling heat exchanger 5. Therefore, the positioner 2 continues to position the thermoelectric conversion module 1 without affecting the distance between the heating heat exchanger 3 and the cooling heat exchanger 5. In addition, the cooling heat exchanger 5 is supported by the guide 95, contactor 71 and stopper 74 so that it cannot move in a direction substantially perpendicular to the stacking direction relative to the base 9. Therefore, the misalignment of the cooling heat exchanger 5 relative to the thermoelectric conversion module 1 in the in-plane direction of the second surface 12 is reduced. As a result, proper contact between the thermoelectric conversion module 1 and the cooling heat exchanger 5 is maintained.

[0068] =Drain Recovery System= Next, an example of the application of the power generation device 10 will be described. The power generation device 10 is incorporated into the drain recovery system 100. Figure 8 is a piping diagram showing the schematic configuration of the drain recovery system 100.

[0069] The drain recovery system 100 recovers the drain generated by the condensation of steam, and also recovers the heat from the flash steam (including steam) generated from the drain. The drain recovery system 100 is an example of a steam system.

[0070] The drain recovery system 100 includes steam-using equipment that receives and uses the supplied steam, and a power generation device 10. More specifically, the drain recovery system 100 includes a gas-liquid separator 110 that separates the incoming drain and steam into drain and steam, a heat recovery unit 140 that recovers heat from the steam separated by the gas-liquid separator 110 via cooling water, a liquid pumping device 150 that pumps the drain separated by the gas-liquid separator 110 to the outside, and a power generation device 10. The drain recovery system 100 further includes a header tank 120 for storing the drain. The liquid pumping device 150 is an example of a pump and an example of steam-using equipment.

[0071] The gas-liquid separator 110 separates the mixed fluid of incoming drain and its flash steam into drain and steam. The gas-liquid separator 110 is connected to an inlet pipe 112, a liquid pipe 113, and a gas pipe 114. Drain and its flash steam generated by steam-using equipment (not shown) outside the drain recovery system 100 flows through the inlet pipe 112. Drain and steam flow into the gas-liquid separator 110 via the inlet pipe 112.

[0072] The gas-liquid separator 110 discharges the separated drain through the liquid pipe 113. The liquid pipe 113 is connected to the header tank 120. The drain is supplied to the header tank 120 via the liquid pipe 113. The gas-liquid separator 110 discharges the separated steam through the gas pipe 114. The gas pipe 114 is connected to the heat recovery unit 140. The steam is supplied to the heat recovery unit 140 via the gas pipe 114.

[0073] The header tank 120 stores drain. In this example, the header tank 120 is a water-sealed header tank. The header tank 120 has a tank body 121 and a water-seal trap 126.

[0074] Drain is stored in the lower part of the internal space of the tank body 121, and steam is stored in the upper part of the internal space of the tank body 121. In other words, the lower part of the internal space is a storage section 123 for storing drain, and the upper part of the internal space is a storage section 124 for storing steam. The liquid pipe 113 is connected to the upper part of the tank body 121 and communicates with the storage section 124. Drain is supplied to the tank body 121 via the liquid pipe 113. The tank body 121 stores drain in the storage section 123 and stores flash steam generated from the drain in the storage section 124.

[0075] An overflow pipe 125 is connected to the tank body 121. The overflow pipe 125 penetrates the tank body 121. One end of the overflow pipe 125 is located in the storage section 123, and the other end of the overflow pipe 125 is located outside the tank body 121. If the amount of drain stored in the storage section 123 of the tank body 121 increases beyond a certain amount, the excess drain flows out to the outside of the tank body 121 via the overflow pipe 125.

[0076] The water seal trap 126 stores sealing water. Under normal circumstances, the water seal trap 126 prevents steam from leaking out of the tank body 121 by its water seal. However, in an emergency when the tank body 121 becomes abnormally high pressure, the water seal is broken, allowing the steam from the tank body 121 to escape into the atmosphere. The internal space of the tank body 121 is sealed by the water seal of the water seal trap 126.

[0077] The water seal trap 126 is connected to the tank body 121 via a connecting pipe 127. One end of the connecting pipe 127 is connected to the upper part of the tank body 121 and communicates with the retention section 124. The other end of the connecting pipe 127 is connected to the water seal trap 126 and communicates with the water storage section of the water seal trap 126. In other words, the other end of the connecting pipe 127 is water-sealed. The water seal trap 126 is also connected to the tank body 121 via an outlet pipe 128. One end of the outlet pipe 128 is connected to the water seal trap 126. The other end of the outlet pipe 128 is located inside the storage section 123 of the tank body 121. The outlet pipe 128 allows excess condensate to flow out of the water seal trap 126 when steam condenses in the water seal trap 126 and the amount of water seal increases. The discharged condensate is supplied to the tank body 121 via the outlet pipe 128.

[0078] The heat recovery unit 140 is a heat exchanger. The heat recovery unit 140 has a first flow path 141 and a second flow path 142. The heat recovery unit 140 performs heat exchange between the fluid flowing through the first flow path 141 and the fluid flowing through the second flow path 142. A gas pipe 114 is connected to the upstream end of the first flow path 141. In other words, steam from the gas-liquid separator 110 flows into the first flow path 141. The downstream end of the first flow path 141 is connected to the tank body 121 via an outlet pipe 144. The downstream end of the outlet pipe 144 is connected to the upper part of the tank body 121 and communicates with the stagnation section 124. A water supply pipe 145 is connected to the upstream end of the second flow path 142 to supply water. Cooling water flows through the water supply pipe 145. An outlet pipe 146 is connected to the downstream end of the second flow path 142 through which water flows out.

[0079] In the heat recovery unit 140, steam supplied from the gas-liquid separator 110 flows into the first channel 141 and circulates through it. Meanwhile, cooling water is supplied to the second channel 142 from the water supply pipe 145 and circulates through it. Heat exchange takes place between the steam circulating in the first channel 141 and the cooling water circulating in the second channel 142. The steam is cooled and condenses, and the cooling water is heated. The drain flows from the first channel 141 through the outlet pipe 144 to the header tank 120 and is stored in the header tank 120. The heated water flows from the second channel 142 to the outlet pipe 146. In this way, the heat recovery unit 140 recovers the heat from the steam using water. The water heated by the recovery of heat is supplied to a desired location or device via the outlet pipe 146.

[0080] The liquid pumping device 150 uses supplied steam to pump the drain. The liquid pumping device 150 supplies the drain from the header tank 120 to a designated drain usage location. The liquid pumping device 150 alternately performs an inflow operation to allow the drain to flow in and store it, and a pumping operation to pump the drain. The liquid pumping device 150 has a casing 151 which is a sealed container, a valve device 152, and a float 153.

[0081] Casing 151 is connected to an inlet pipe 154 through which drain water flows in, and an outlet pipe 155 through which drain water flows out. The upstream end of the inlet pipe 154 is connected to a header tank 120. More specifically, the inlet pipe 154 is connected to the lower part of the tank body 121 and communicates with the storage section 123. The inlet pipe 154 is equipped with a check valve 156 that allows flow only from the header tank 120 to the casing 151. The outlet pipe 155 is connected to a relatively lower part of the casing 151, more specifically, at least below the connection port of the inlet pipe 154. The downstream end of the outlet pipe 155 is connected to a drain usage location. The outlet pipe 155 is equipped with a check valve 157 that allows flow only in the direction of outflow from the casing 151. More specifically, the check valve 157 is closed by an elastic member such as a spring and opens when a pressure exceeding a predetermined opening pressure is applied.

[0082] The internal space of the casing 151 serves as a drain storage space. A float 153 is also positioned within the internal space of the casing 151. The float 153 is formed in a hollow spherical shape. A lever 153a is connected to the float 153. The lever 153a is supported by the casing 151 so as to be rotatable around a predetermined axis of rotation. The float 153 floats in the drain inside the casing 151. The float 153 moves up and down according to the amount of drain stored in the casing 151. At this time, the lever 153a rotates around the axis of rotation in accordance with the up and down movement of the float 153.

[0083] The casing 151 is connected to a supply pipe 158 that supplies steam as the working gas and a discharge pipe 159 that discharges steam from the casing 151. High-pressure steam flows through the supply pipe 158. The downstream end of the supply pipe 158 is connected to a valve device 152. The upstream end of the discharge pipe 159 is connected to a valve device 152. The downstream end of the discharge pipe 159 is connected to a header tank 120.

[0084] The valve device 152, although not shown in the figures, includes an air intake valve and an exhaust valve. The air intake valve is located at the downstream end of the supply pipe 158. The air intake valve switches the supply pipe 158 open and closed. The exhaust valve is located at the upstream end of the discharge pipe 159. The exhaust valve switches the discharge pipe 159 open and closed. Furthermore, the valve device 152 has a switching mechanism that switches the opening and closing of the air intake valve and the exhaust valve. The switching mechanism switches between an air intake state, in which the air intake valve is open and the exhaust valve is closed, and an exhaust state, in which the air intake valve is closed and the exhaust valve is open. A lever 153a extending from the float 153 is connected to the switching mechanism. The switching mechanism is driven by the lever 153a and switches between the air intake state and the exhaust state.

[0085] More specifically, when the float 153 is located at a relatively low position within the casing 151, the switching mechanism is in the exhaust state. When the float 153 rises to a predetermined first switching position, the lever 153a switches the switching mechanism from the exhaust state to the intake state. In the intake state of the switching mechanism, when the float 153 descends to a second switching position lower than the first switching position, the lever 153a switches the switching mechanism from the intake state to the exhaust state.

[0086] In the liquid pumping device 150 configured in this way, when the switching mechanism is in the exhaust state, the supply pipe 158 is shut off and the discharge pipe 159 is open. The float 153 is located at a relatively low position inside the casing 151. In this state, the pressure inside the header tank 120 causes the drain from the header tank 120 to flow into the casing 151 via the inlet pipe 154. If the differential pressure between the inlet pressure and back pressure acting on the check valve 157 is less than the opening pressure of the check valve 157, the check valve 157 remains closed, and the drain is stored in the casing 151. As the drain flows into the casing 151, the steam inside the casing 151 flows out to the discharge pipe 159 via the exhaust valve. The steam that flows out to the discharge pipe 159 flows into the header tank 120. In this way, the liquid pumping device 150 performs the inflow operation.

[0087] During the inflow operation, the float 153 rises as the amount of drain stored increases. As the float 153 rises, the lever 153a rotates around its axis. When the float 153 rises to the first switching position, the lever 153a switches the switching mechanism of the valve device 152 from exhaust to supply. The supply pipe 158 opens and the discharge pipe 159 is closed. As a result, the liquid pumping device 150 switches from inflow operation to pumping operation.

[0088] During the pumping operation, steam is supplied into the casing 151 via the supply pipe 158. When the pressure inside the casing 151 rises, the check valve 156 closes, stopping the inflow of condensate into the casing 151 via the inlet pipe 154, and also preventing backflow of steam from the casing 151 to the header tank 120 via the inlet pipe 154. Furthermore, when the differential pressure between the inlet pressure and back pressure acting on the check valve 157 exceeds the opening pressure of the check valve 157, the check valve 157 opens, and the condensate inside the casing 151 flows out into the outlet pipe 155. The condensate is then supplied to the point of use via the outlet pipe 155.

[0089] During the pumping operation, the inflow of drain from the inlet pipe 154 stops, so the amount of drain stored decreases. As the amount of drain stored decreases, the float 153 descends. As the float 153 descends, the lever 153a rotates around its axis. When the float 153 descends to the second switching position, the lever 153a switches the switching mechanism of the valve device 152 from the supply state to the exhaust state. The supply pipe 158 is shut off and the discharge pipe 159 is opened. In this way, the liquid pumping device 150 switches from pumping operation to inflow operation. Eventually, as the pressure inside the casing 151 decreases, the check valve 156 opens, and the inflow of drain from the inlet pipe 154 begins.

[0090] In this way, the liquid pumping device 150 uses steam as a power source to supply the drain from the header tank 120 to the drain usage location.

[0091] The power generation device 10 is supplied with a portion of the steam before it is supplied to the liquid pumping device 150, as well as a portion of the cooling water before it is supplied to the heat recovery device 140.

[0092] More specifically, an inlet pipe 161, which branches off from the supply pipe 158, is connected to the inlet port 31 of the heating heat exchanger 3. An outlet pipe 162 is connected to the outlet port 32 of the heating heat exchanger 3. The downstream end of the outlet pipe 162 is connected to the gas pipe 114. Steam flowing through the supply pipe 158 flows into the heating heat exchanger 3 via the inlet pipe 161. Drain or steam flowing out of the heating heat exchanger 3 flows out to the gas pipe 114 via the outlet pipe 162. Note that the downstream end of the outlet pipe 162 may be connected to the inlet pipe 112 or the liquid pipe 113 instead of the gas pipe 114.

[0093] Meanwhile, an inlet pipe 163, which branches off from the water supply pipe 145, is connected to the inlet port 51 of the cooling heat exchanger 5. An outlet pipe 164 is connected to the outlet port 52 of the cooling heat exchanger 5. The downstream end of the outlet pipe 164 is connected to the part of the water supply pipe 145 downstream of the branch to the inlet pipe 163. Water flowing through the water supply pipe 145 flows into the cooling heat exchanger 5 via the inlet pipe 163. Water flowing out of the cooling heat exchanger 5 returns to the water supply pipe 145 via the outlet pipe 164.

[0094] In this way, steam is supplied to the heating heat exchanger 3 and water is supplied to the cooling heat exchanger 5, causing the first surface 11 of the thermoelectric conversion module 1 to be heated and the second surface 12 to be cooled. As a result, thermoelectric power generation is performed in the power generation device 10.

[0095] In this manner, the drain recovery system 100 recovers the drain and supplies the recovered drain to the drain usage location via the liquid pumping device 150. Furthermore, the drain recovery system 100 recovers the heat of the flash steam generated from the drain using cooling water via the heat recovery unit 140. The power generation device 10 generates electricity by utilizing the steam used in the drain recovery system 100, specifically the steam used in the liquid pumping device 150. Furthermore, the power generation device 10 increases the amount of electricity generated by utilizing the cooling water used in the drain recovery system 100, specifically the cooling water used in the heat recovery unit 140.

[0096] In steam systems such as the drain recovery system 100, there may be excess thermal energy from the steam. In such cases, the thermal energy of the steam used in the drain recovery system 100 can be effectively utilized for power generation. Furthermore, the power generation device 10 can function as a local power source. For example, power can be secured without installing a power source or laying power lines from a power source.

[0097] As described above, in the power generation device 10, the bent portions 83 of the two springs 8, which are aligned in a predetermined direction in a plane parallel to the first surface 11 and the second surface 12, face different directions. Therefore, it is possible to suppress uneven distribution of the portion pressed by the springs 8 on the pressing surface of the cooling heat exchanger 5. That is, by making the directions of the bent portions 83 of the two springs 8 different, the positions of the free ends of the second plates 82 of the two springs 8 can be distributed as widely as possible on the pressing surface. This allows for a wider distribution of the portion pressed by the springs 8 on the pressing surface. Therefore, the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1 can be increased, improving power generation efficiency. Consequently, it is possible to suppress the decrease in power generation efficiency caused by uneven distribution of the portion pressed by the springs 8 on the heat exchanger.

[0098] Furthermore, the cooling heat exchanger 5, which is pressed by the free end of the second plate, has a roughly rectangular body 50 that is formed in a rectangular shape extending in a predetermined longitudinal direction that coincides with a predetermined direction, and has an outer surface (pressing surface) of the second wall 54 that is pressed by the free end of the second plate 82, and the outer surface of the first wall 53 on the body 50, which is facing opposite to the outer surface of the second wall 54, is in contact with the second surface 12. The bent portions 83 of two adjacent springs 8 in a predetermined direction are facing opposite directions to each other in the short direction of the second wall 54. As a result, the pressing force from the springs 8 can be applied evenly to the front and rear sides in the longitudinal direction of the second wall 54 and, consequently, the body 50. This increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1, and improves the power generation efficiency. Furthermore, the adverse effect on the degree of adhesion is greater when the pressing force of the spring 8 is unevenly distributed in the longitudinal direction of the main body 50 than when it is unevenly distributed in the short direction of the main body 50. In this example, the pressing force of the spring 8 acts evenly in the longitudinal direction of the main body 50, so the degree of adhesion can be effectively improved.

[0099] Furthermore, the power generation device 10 is further equipped with a contactor 71 which is formed in the shape of a flat plate extending in a plane parallel to the first surface 11 and the second surface 12, and which contacts the cooling heat exchanger 5 pressed by the free end of the second plate 82. The free ends of the second plate 82 of the two springs 8 press against the cooling heat exchanger 5 via the contactor 71. Therefore, compared to, for example, the case where the springs 8 directly press against the cooling heat exchanger 5, the pressing force from the springs 8 can be applied more evenly to the second wall 54 (pressing surface) of the cooling heat exchanger 5. In other words, the pressing force from the springs 8 acts evenly throughout the entire contactor 71, and the pressing force from the contactor 71 acts more evenly over the entire second wall 54 of the cooling heat exchanger 5. This further increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1.

[0100] Variant form Figure 8 is an exploded perspective view of the modified thermoelectric conversion module 1, cooling heat exchanger 5, and presser 7. Figure 9 is a front view showing the assembled state of the modified thermoelectric conversion module 1, cooling heat exchanger 5, and presser 7. This modified version changes the configuration of the cooling heat exchanger 5 and presser 7 in the above embodiment. The differences from the above embodiment will be explained here.

[0101] In this modified example, four thermoelectric conversion modules 1 are provided. The four thermoelectric conversion modules 1 are arranged in two rows, with two thermoelectric conversion modules 1 in each row. In other words, the four thermoelectric conversion modules 1 as a whole are arranged in a roughly square plate shape. Note that the number of thermoelectric conversion modules 1 in each row may be three or more.

[0102] The cooling heat exchanger 5, like the embodiment described above, has a container-shaped body 50A and an inlet port 51A and an outlet port 52A. The body 50A is formed in a substantially rectangular tubular shape, that is, a substantially rectangular parallelepiped shape, extending in a predetermined longitudinal direction. The body 50A has a first wall 53A, a second wall 54A, a third wall 55A, a fourth wall 56A, a fifth wall 57A, and a sixth wall 58A. The first wall 53 and the second wall 54 are formed in a substantially square shape and face each other. The third wall 55A, the fourth wall 56A, the fifth wall 57A, and the sixth wall 58A are formed in a substantially rectangular shape. Each side of the first wall 53A is connected to one of the longer sides of the third wall 55A, the fourth wall 56A, the fifth wall 57A, and the sixth wall 58A. Each side of the second wall 54A is connected to the other longer side of the third wall 55A, fourth wall 56A, fifth wall 57A, and sixth wall 58A. The third wall 55A and the fifth wall 57A face each other, and the fourth wall 56A and the sixth wall 58A face each other. In other words, in this example of the cooling heat exchanger 5, the outer surface of the second wall 54A, which is the pressing surface, is formed in a roughly square shape.

[0103] In this example, for the sake of explanation, in the main body 50A, the direction in which the longitudinal direction of the fourth wall 56A and the sixth wall 58A is the same as the left-right direction, and the direction perpendicular to both the left-right direction and the stacking direction is the front-back direction (i.e., the same direction as the longitudinal direction of the third wall 55A and the fifth wall 57A). The inlet port 51A is provided at one end of the main body 50A in the left-right direction, and the outlet port 52A is provided at the other end of the main body 50A in the left-right direction. More specifically, the inlet port 51A is located at the end of the fifth wall 57A closest to the sixth wall 58A. The outlet port 52A is located at the end of the third wall 55A closest to the fourth wall 56A. In this cooling heat exchanger 5, the outer surface of the first wall 53A is a cooling surface that is in contact with the second surface 12 of each of the four thermoelectric conversion modules 1.

[0104] The presser 7 has four springs 8 and a contactor 71A. When distinguishing between the four springs 8, they are referred to as the first spring 8A, the second spring 8B, the third spring 8C, and the fourth spring 8D. Each of these springs 8 also has a first plate 81, a second plate 82, and a bent portion 83, with the first plate 81 fixed to the main body 90 of the base 9 with screws. Each spring 8 presses the cooling heat exchanger 5 toward the heating heat exchanger 3 via the contactor 71. That is, the free end of the second plate 82 of each spring 8 presses the cooling heat exchanger 5 via the contactor 71.

[0105] In this example as well, the four springs 8 are arranged in a predetermined direction within a plane parallel to the first surface 11 and the second surface 12, and are positioned such that the directions of the bent portions 83 of two adjacent springs 8 in the predetermined direction are different from each other. Specifically, the first spring 8A and the second spring 8B are arranged in a single row in the left-right direction of the main body 50A, and the third spring 8C and the fourth spring 8D are arranged in a separate row in the left-right direction of the main body 50A. Also, the first spring 8A and the fourth spring 8D are arranged in a single row in the front-rear direction of the main body 50A, and the second spring 8B and the third spring 8C are arranged in a separate row in the front-rear direction of the main body 50A. In other words, the first plates 81 of the four springs 8 as a whole are arranged in a roughly square plate shape. In this example, the predetermined direction is both the left-right direction and the front-rear direction of the main body 50A.

[0106] The four springs 8 have different directions in which their bent portions 83 face. That is, in the left-right direction of the main body 50A, the bent portions 83 of adjacent first springs 8A and second springs 8B face different directions, and similarly, the bent portions 83 of adjacent third springs 8C and fourth springs 8D face different directions, and similarly, the bent portions 83 of adjacent second springs 8B and third springs 8C face different directions, and similarly, the bent portions 83 of adjacent second springs 8B and third springs 8C face different directions, in the front-rear direction of the main body 50A.

[0107] More specifically, the bent portion 83 of the first spring 8A faces away from the second spring 8B in the left-right direction of the main body 50A. The bent portion 83 of the second spring 8B faces away from the third spring 8C in the front-rear direction of the main body 50A. The bent portion 83 of the third spring 8C faces away from the fourth spring 8D in the left-right direction of the main body 50A. The bent portion 83 of the fourth spring 8D faces away from the first spring 8A in the front-rear direction of the main body 50A. In this way, the four springs 8 are arranged so that the directions of their bent portions 83 are different from each other.

[0108] By arranging the four springs 8 in this manner, as shown in Figure 8, the portion pressed by the springs 8 in the contactor 71 can be widely distributed in the left-right and front-back directions of the main body 50A. In other words, the positions of the free ends of the second plates 82 of the four springs 8 can be widely distributed in the contactor 71. This increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1, improving power generation efficiency. Therefore, it is possible to suppress the decrease in power generation efficiency caused by uneven pressure distribution of the springs 8 against the heat exchangers. Other configurations, operations, and effects are the same as in the above embodiment.

[0109] Other embodiments As described above, the embodiments described herein have been presented as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited thereto and can be applied to embodiments that have been modified, replaced, added, or omitted as appropriate. Furthermore, it is possible to combine the components described in the embodiments above to create new embodiments. In addition, the components described in the attached drawings and detailed description may include not only components essential for solving the problem, but also components that are not essential for solving the problem, in order to illustrate the technology. Therefore, the mere presence of such non-essential components in the attached drawings and detailed description should not be immediately assumed to mean that those non-essential components are essential.

[0110] For example, the cross-sectional shape of the side wall 33 may be a polygon other than a quadrilateral.

[0111] Furthermore, the stacking direction of the heating heat exchanger 3 and the cooling heat exchanger 5 does not have to be vertical. The stacking direction of the heating heat exchanger 3 and the cooling heat exchanger 5 may be horizontal, or it may be inclined relative to the vertical direction. Moreover, the heating heat exchanger 3 may be positioned above the cooling heat exchanger 5.

[0112] Furthermore, the cooling heat exchanger 5 may be a fixed heat exchanger with a fixed configuration, while the heating heat exchanger 3 may be a movable heat exchanger. For example, the base 9 may be attached to the cooling heat exchanger 5, and the thermoelectric conversion module 1, the heating heat exchanger 3, and the presser 7 may be arranged between the base 9 and the cooling heat exchanger 5. That is, in the power generation device 10 shown in Figure 1, the positions of the heating heat exchanger 3 and the cooling heat exchanger 5 may be swapped, and the first surface 11 and the second surface 12 of the thermoelectric conversion module 1 may be reversed. In that case, the presser 7 presses the heating heat exchanger 3 toward the cooling heat exchanger 5 in the stacking direction, and the stopper 74 of the contactor 71 restricts the displacement of the heating heat exchanger 3 in the in-plane direction of the first surface 11. This reduces the misalignment between the heating heat exchanger 3 and the thermoelectric conversion module 1 in the in-plane direction of the first surface 11.

[0113] Furthermore, the base 9 is attached to one of the heating heat exchanger 3 and the cooling heat exchanger 5, but is not limited to this. Two bases 9 may be provided on both sides of the heating heat exchanger 3 and the cooling heat exchanger 5 in the stacking direction, and configured to sandwich the heating heat exchanger 3 and the cooling heat exchanger 5.

[0114] Furthermore, the number of thermoelectric conversion modules 1 is not limited to four, and may be less than four or more than four. The shape of the thermoelectric conversion module 1 may be any shape as long as it has a first surface 11 and a second surface 12 facing opposite directions. For example, the thermoelectric conversion module 1 may be roughly rectangular, roughly triangular, or roughly hexagonal in plan view. The thermoelectric conversion module 1 may be block-shaped rather than plate-shaped. The arrangement of multiple thermoelectric conversion modules 1 does not have to be linear. Multiple thermoelectric conversion modules 1 may be arranged in two dimensions.

[0115] Furthermore, the configuration of the heating heat exchanger 3 and the cooling heat exchanger 5 is not limited to the shapes described above, and any configuration is acceptable as long as it can appropriately exchange heat with the first surface 11 and the second surface 12. For example, in the heating heat exchanger 3, one heating surface 36 may be provided for multiple thermoelectric conversion modules 1. That is, the four heating surfaces 36 described above may be connected to form one heating surface 36. In the cooling heat exchanger 5, instead of one cooling surface 59, multiple divided cooling surfaces may be provided for multiple thermoelectric conversion modules 1.

[0116] Furthermore, the configuration of the positioning device 2 is not limited to the configuration described above. For example, the frame 20 of the positioning device 2 may be closed rather than open. That is, the frame 20 may not have a notch and may have a shape that follows the entire circumference of the outer shape of the thermoelectric conversion module 1 in a plane substantially parallel to the first surface 11 (or second surface 12). Also, the number of mounting parts 21 may be one or three or more. The through hole 21a may have a shape other than circular.

[0117] Furthermore, the shaft 25a is not limited to a cylinder and may have a cross-sectional shape other than a circle. The support 25 may support the positioning device 2 by a member other than the shaft 25a. For example, the support 25 may be a projection provided on the heating heat exchanger 3 or the cooling heat exchanger 5. The positioning device 2 may be supported by the support 25 such that the projection is inserted into the through hole 21a of the positioning device 2.

[0118] Furthermore, the support 25 may support the positioning device 2 so that it can be displaced within a predetermined range in the in-plane direction of the second surface 12. For example, the shaft 25a may extend in a direction intersecting the second surface 12. However, if the second surface 12 is substantially parallel to the first surface 11, supporting the positioning device 2 so that it can be displaced within a predetermined range in the in-plane direction of the first surface 11 is equivalent to supporting the positioning device 2 so that it can be displaced within a predetermined range in the in-plane direction of the second surface 12.

[0119] Furthermore, the support 25, specifically the shaft 25a, may be provided on the cooling heat exchanger 5. That is, the shaft 25a may extend from the cooling heat exchanger 5 in a direction intersecting the first surface 11 or the second surface 12, more specifically in a substantially orthogonal direction. In this case, the positioner 2 is supported by the cooling heat exchanger 5 via the shaft 25a, and the thermoelectric conversion module 1 is positioned substantially relative to the cooling heat exchanger 5.

[0120] Furthermore, the contactor 71 may be omitted from the presser 7. In that case, the spring 8 will be in direct contact with the movable heat exchanger among the heating heat exchanger 3 and the cooling heat exchanger 5.

[0121] Furthermore, the stopper 74 does not have to be formed in the shape of a plate. For example, the stopper 74 may be formed by a shaft or a block or the like. The stopper 74 can be of any shape as long as it is positioned adjacent to the movable heat exchanger among the heating heat exchanger 3 and the cooling heat exchanger 5 and restricts the displacement of the movable heat exchanger.

[0122] Furthermore, a heating fluid other than steam may be supplied to the main body 30 of the heating heat exchanger 3, and a liquid other than water may be supplied to the main body 50 of the cooling heat exchanger 5.

[0123] The number of springs 8 arranged in a row is not limited to 2; it may be 3 or more.

[0124] The number of rows of spring 8 is not limited to one or two rows; it may be three or more rows.

[0125] The shapes of the first plate 81 and the second plate 82 of the spring 8 are not limited to rectangles, but may be square, for example.

[0126] The power generation device 10 may be installed in a steam system other than the drain recovery system 100. In that case, a portion of the steam used in the steam system may be supplied to the heating heat exchanger 3.

[0127] The technology disclosed in this disclosure can be summarized as follows:

[0128] [1] The power generation device 10 includes a thermoelectric conversion module 1 having a first surface 11 and a second surface 12 facing opposite directions, which generates thermoelectric power according to the temperature difference between the first surface 11 and the second surface 12; a heating heat exchanger 3 that is in contact with the first surface 11 and heats the first surface 11; a cooling heat exchanger 5 that is in contact with the second surface 12 and cools the second surface 12; a first plate 81 parallel to the first surface 11 and the second surface 12; a second plate 82 extending diagonally with respect to the first plate 81; and a bending portion 83 that connects the first plate 81 and the second plate 82 in a substantially V-shape, which elastically deforms so that the free end of the first plate 81 and the free end of the second plate 82 move closer together or further apart, and a plurality of springs 8 whose free end presses one of the heating heat exchanger 3 and the cooling heat exchanger 5 toward the other. The plurality of springs 8 are arranged in a predetermined direction in a plane parallel to the first surface 11 and the second surface 12, and are arranged such that the direction in which the bent portions of two adjacent springs face is different from that of the other two springs in the predetermined direction.

[0129] With this configuration, since the bent portions 83 of two adjacent springs 8 aligned in a predetermined direction face different directions, it is possible to suppress uneven distribution of the portion pressed by the springs 8 on the pressing surface of the heating heat exchanger 3 or the cooling heat exchanger 5. As a result, the portion pressed by the springs 8 can be widely distributed on the pressing surface. Therefore, the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1 can be increased, improving power generation efficiency. Consequently, it is possible to suppress the decrease in power generation efficiency caused by uneven distribution of the portion pressed by the springs 8 on the heat exchanger.

[0130] [2] In the power generation device 10 described in [1], the heating heat exchanger 3 or the cooling heat exchanger 5 pressed by the free end of the second plate 82 has a substantially rectangular parallelepiped body that is formed in a rectangular shape extending in a predetermined longitudinal direction coinciding with the predetermined direction and has a pressing surface that is pressed by the free end of the second plate 12, and the surface of the body opposite to the pressing surface is in contact with the first surface 11 or the second surface 12. The bent portions 83 of two adjacent springs 8 in the predetermined direction are oriented in opposite directions to each other in the short direction of the pressing surface.

[0131] This configuration allows the pressing force from the spring 8 to be applied evenly to both the front and rear sides in the longitudinal direction of the pressing surface, i.e., in the longitudinal direction of the main body. This increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1, thereby improving power generation efficiency. Furthermore, an uneven distribution of the pressing force from the spring 8 in the longitudinal direction of the main body has a greater negative impact on the aforementioned degree of contact than an uneven distribution in the short direction of the main body. However, with this technology, the pressing force from the spring 8 is applied evenly in the longitudinal direction of the main body, thus effectively increasing the aforementioned degree of contact.

[0132] [3] The power generation device 10 described in [1] or [2] further comprises a contactor 71 which is formed in the shape of a flat plate that extends in a plane parallel to the first surface 11 and the second surface 12, and which is in contact with the heating heat exchanger 3 or the cooling heat exchanger 5 that is pressed by the free end of the second plate 82. The free ends of the second plates 82 of the plurality of springs 8 press the heating heat exchanger 3 or the cooling heat exchanger 5 that are in contact with the contactor 71 via the contactor 71.

[0133] With this configuration, for example, compared to the case where the spring 8 directly contacts and presses against the cooling heat exchanger 5, the pressing force from the spring 8 can be applied more evenly to the pressing surface of the cooling heat exchanger 5. In other words, the pressing force from the spring 8 acts evenly across the entire contactor 71, and the pressing force from the contactor 71 acts more evenly across the entire second wall 54 of the cooling heat exchanger 5. This further increases the degree of contact between the cooling heat exchanger 5 and the heating heat exchanger 3 and the thermoelectric conversion module 1. Therefore, the decrease in power generation efficiency caused by uneven pressure distribution on the heat exchanger by the spring 8 can be further suppressed.

[0134] [4] The drain recovery system 100 (steam system) comprises steam-using equipment to which steam is supplied and which uses the supplied steam, and a power generation device 10 as described in any one of [1] to [3], wherein a portion of the steam before it is supplied to the steam-using equipment is supplied to the heating heat exchanger 3.

[0135] In this configuration, the heating heat exchanger 3 utilizes a portion of the steam supplied to the steam-using equipment included in the drain recovery system 100 to heat the thermoelectric conversion module 1. In other words, the thermal energy of the steam used in the drain recovery system 100 can be effectively utilized for power generation. Furthermore, the power generation device 10 can function as a local power source in the drain recovery system 100.

[0136] [5] [4] The drain recovery system 100 includes a gas-liquid separator 110 that separates the incoming drain and steam into drain and steam, a heat recovery unit 140 that recovers heat from the steam separated by the gas-liquid separator 110 via cooling water, and a liquid pumping device 150 (pump) that pumps the drain separated by the gas-liquid separator 110 to the outside, wherein the liquid pumping device 150 is the steam-using equipment and pumps the drain using the supplied steam, and a portion of the cooling water before it is supplied to the heat recovery unit 140 is supplied to the cooling heat exchanger 5.

[0137] With this configuration, the power generation device 10 can generate electricity by utilizing the steam used in the liquid pumping device 150 and the cooling water used in the heat recovery device 140. [Explanation of symbols]

[0138] 10 Power generation equipment 1 Thermoelectric Conversion Module 3 Heating heat exchanger 5 Cooling heat exchanger 8 springs 11 Page 1 12 Side 2 50 Main Unit 71 Contactor 81 1st board 82 2nd board 83. Bending section 100 Drain Recovery System (Steam System) 110 Gas-liquid separator 140 Heat Recovery Unit 150 Liquid pumping equipment (pumps, steam-using equipment)

Claims

1. A thermoelectric conversion module having a first surface and a second surface facing opposite directions, which generates thermoelectric power according to the temperature difference between the first surface and the second surface, A heating heat exchanger that contacts the first surface and heats the first surface, A cooling heat exchanger that is in contact with the second surface and cools the second surface, The device comprises a first plate parallel to the first and second surfaces, a second plate extending diagonally from the first plate, and a bent portion connecting the first and second plates in a substantially V-shape, the first plate and the second plate being elastically deformable so that their free ends move closer together or further apart, and the free end of the second plate pressing one of the heating heat exchanger and the cooling heat exchanger toward the other, The plurality of springs are arranged in a predetermined direction within a plane parallel to the first and second planes, and the direction in which the bent portions of two adjacent springs face is different in that predetermined direction. A power generation device characterized by the following features.

2. In the power generation apparatus according to claim 1, The heating heat exchanger or cooling heat exchanger pressed by the free end of the second plate has a substantially rectangular parallelepiped body formed in a rectangular shape extending in a predetermined longitudinal direction coinciding with the predetermined direction, and having a pressing surface that is pressed by the free end of the second plate, and the surface of the body opposite to the pressing surface is in contact with the first surface or the second surface, The bent portions of the two adjacent springs in the predetermined direction are oriented in opposite directions in the short-side direction of the pressing surface. A power generation device characterized by the following features.

3. In the power generation apparatus according to claim 1, The device further comprises a contactor formed in the shape of a flat plate extending in a plane parallel to the first and second surfaces, which is pressed by the free end of the second plate against the heating heat exchanger or the cooling heat exchanger, The free ends of the second plates of the plurality of springs press the heating heat exchanger or the cooling heat exchanger that contacts the contactor via the contactor. A power generation device characterized by the following features.

4. Steam is supplied, and steam-using equipment uses the supplied steam, The power generation device is as described in claim 1, A portion of the steam before it is supplied to the steam-using equipment is supplied to the aforementioned heating heat exchanger. A steam system characterized by the following features.

5. In the steam system according to claim 4, A gas-liquid separator that separates the incoming drain and steam into drain and steam, A heat recovery unit that recovers heat from the steam separated by the gas-liquid separator via cooling water, The system includes a pump that pumps the drain separated by the gas-liquid separator to the outside, The aforementioned pump is the steam-using equipment, and uses the supplied steam to pump the drain. A portion of the cooling water before it is supplied to the heat recovery unit is supplied to the cooling heat exchanger. A steam system characterized by the following features.

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