Power generation device and steam system

Abstract

A power generation device 10 includes: a thermoelectric conversion module 1 that has a first surface 11 and a second surface 12 opposite to each other in the horizontal direction, and performs thermoelectric power generation according to the temperature difference between the first surface 11 and the second surface 12; a fixed-type heating heat exchanger 3 in which the thermoelectric conversion module 1 is disposed on both sides in the horizontal direction and in contact with the first surface 11, and that heats the first surface 11; two movable-type cooling heat exchangers 4 that are in contact with the second surface 12 of the thermoelectric conversion module 1 disposed on both sides of the heating heat exchanger 3 in the horizontal direction, and that cool the second surface 12; a pressing device 5 that elastically presses one of the two cooling heat exchangers 4 toward the heating heat exchanger 3 in the horizontal direction; and a pair of bases 6 that horizontally sandwiches the heating heat exchanger 3, the thermoelectric conversion module 1, the two cooling heat exchangers 4, and the pressing device 5. The pair of bases 6 are integrally formed with each other and arranged so as to be displaceable in the horizontal direction.

Description

Power Generation and Steam Systems

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

[0002] Power generation devices that generate thermoelectric power using a thermoelectric conversion element have been known for some time. For example, in a power generation device disclosed in Patent Document 1, a thermoelectric conversion element is provided between an inner tube through which exhaust gas flows and a heat dissipation fin. In this power generation device, the high-temperature side of the thermoelectric conversion element is heated by the exhaust gas, and the low-temperature side of the thermoelectric conversion element is cooled by the heat dissipation fin. This generates a temperature difference between the high-temperature side and the low-temperature side, resulting in thermoelectric power generation.

[0003] Japanese Patent Application Publication No. 10-234194

[0004] In a power generation device in which a heating heat exchanger and a cooling heat exchanger are in contact with both sides of a thermoelectric conversion module as described above, a presser may be provided to press the cooling heat exchanger toward the heating heat exchanger to ensure that the heat exchanger and the cooling heat exchanger are in contact with each other, for example, when the heating heat exchanger expands or deforms. Maintaining contact between the thermoelectric conversion module and the heating heat exchanger improves power generation efficiency. To more effectively utilize the heating heat exchanger, it is also possible to place the thermoelectric conversion module and the cooling heat exchanger on both sides of the heating heat exchanger, rather than just one side. However, in such a case, if the heating heat exchanger is fixedly installed for various reasons, two sets of pressers to press the cooling heat exchanger toward the heating heat exchanger are required, resulting in an increase in the size of the device.

[0005] The technology of the present disclosure has been made in consideration of the above circumstances, and its purpose is to achieve both improved power generation efficiency and compactness in a power generation device in which a heating heat exchanger is fixedly installed.

[0006] The power generation device of the present disclosure includes a thermoelectric conversion module, a fixed heating heat exchanger, two movable cooling heat exchangers, a presser, and a pair of bases. The thermoelectric conversion module has a first surface and a second surface facing opposite each other in a predetermined horizontal direction, and generates thermoelectric power in response to a temperature difference between the first surface and the second surface. The heating heat exchanger has the thermoelectric conversion modules arranged on both sides in the horizontal direction and contacts the first surface to heat the first surface. The two cooling heat exchangers contact the second surfaces of the thermoelectric conversion modules arranged on both sides of the heating heat exchanger in the horizontal direction and cool the second surfaces. The presser is arranged on the opposite side of one of the two cooling heat exchangers from the thermoelectric conversion module in the horizontal direction, and elastically presses the one cooling heat exchanger toward the heating heat exchanger. The pair of bases sandwich the heating heat exchanger, the thermoelectric conversion module, the two cooling heat exchangers, and the pressing device in the horizontal direction. The pair of bases are integrally formed with each other and are disposed so as to be displaceable in the horizontal direction.

[0007] The steam system of the present disclosure includes a steam-using device that receives a supply of steam and uses the supplied steam, and the power generation device described above. The heating heat exchanger receives the steam before being supplied to the steam-using device, and heats the first surface with the supplied steam.

[0008] According to the power generating device, it is possible to improve the power generating efficiency and make the device compact.

[0009] The steam system described above can achieve both improved power generation efficiency and compactness.

[0010] FIG. 1 is an exploded perspective view of the power generating device as viewed from the first base side. FIG. 2 is an exploded perspective view of the power generating device as viewed from the second base side. FIG. 3 is a front view of the power generating device with a portion of the second base omitted. FIG. 4 is a plan view of the power generating device with the top plate omitted. FIG. 5 is a cross-sectional view of a heating heat exchanger and a drain trap. FIG. 6 is an enlarged cross-sectional view of a shaft and a slider of a support. FIG. 7 is a diagram schematically showing displacement of a cooling heat exchanger, etc. FIG. 8 is a piping diagram showing the general configuration of a drain recovery system.

[0011] Exemplary embodiments will now be described in detail with reference to the accompanying drawings.

[0012] Fig. 1 is an exploded perspective view of the power generating device 10 as viewed from the first base 6A side. Fig. 2 is an exploded perspective view of the power generating device 10 as viewed from the second base 6B side. Fig. 3 is a front view of the power generating device 10 with a portion of the second base 6B omitted. Fig. 4 is a plan view of the power generating device 10 with the top plate 67 omitted.

[0013] The power generation device 10 is a thermoelectric power generation device that generates electricity. The power generation device 10 includes a thermoelectric conversion module 1 that generates thermoelectric power by converting thermal energy into electrical energy, a heating heat exchanger 3 that heats the thermoelectric conversion module 1, two cooling heat exchangers 4 that cool the thermoelectric conversion module 1, a presser 5, and a pair of bases 6. When the two cooling heat exchangers 4 are described separately, they are referred to as a first cooling heat exchanger 4A and a second cooling heat exchanger 4B, and when the pair of bases 6 are described separately, they are referred to as a first base 6A and a second base 6B.

[0014] The heating heat exchanger 3 is disposed between the first cooling heat exchanger 4A and the second cooling heat exchanger 4B, and the thermoelectric conversion module 1 is disposed between the heating heat exchanger 3 and the first cooling heat exchanger 4A and between the heating heat exchanger 3 and the second cooling heat exchanger 4B. The heating heat exchanger 3 is a fixedly installed heat exchanger, and the first cooling heat exchanger 4A and the second cooling heat exchanger 4B are movable heat exchangers that are displaceably installed. In the power generation device 10, the heating heat exchanger 3 and the two cooling heat exchangers 4 generate a temperature difference in the thermoelectric conversion module 1, and the thermoelectric conversion module 1 generates power in response to the temperature difference.

[0015] The presser 5 elastically presses only one of the two cooling heat exchangers 4 toward the heating heat exchanger 3. The presser 5 is disposed on the opposite side of the cooling heat exchanger 4 that it presses from the thermoelectric conversion module 1. The pair of bases 6 sandwich the thermoelectric conversion module 1, the heating heat exchanger 3, the cooling heat exchanger 4, etc.

[0016] The power generation device 10 further includes a coupler 7 that connects the pair of bases 6 to each other and thereby sandwiches the pair of bases 6 therebetween.

[0017] The power generation device 10 further includes a positioning device 2 that positions the thermoelectric conversion module 1. More specifically, the power generation device 10 includes two positioning devices 2. The two positioning devices 2 position the thermoelectric conversion module 1 between the first cooling heat exchanger 4A and the heating heat exchanger 3, and the thermoelectric conversion module 1 between the second cooling heat exchanger 4B and the heating heat exchanger 3.

[0018] In the power generation device 10, the first base 6A, the first cooling heat exchanger 4A, the thermoelectric conversion module 1, the heating heat exchanger 3, the thermoelectric conversion module 1, the second cooling heat exchanger 4B, the presser 5, and the second base 6B are stacked in this order. The direction in which the heating heat exchanger 3 and other components are stacked is referred to as the "stacking direction." The stacking direction coincides with a predetermined horizontal direction and with the pressing direction of the presser 5.

[0019] The power generation device 10 further includes a support 8 that supports the cooling heat exchanger 4 and the positioning device 2 so that they can be displaced in the stacking direction. In other words, the cooling heat exchanger 4 and the positioning device 2 are supported so that they can be displaced in the pressing direction of the pressing device 5.

[0020] =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. The thermoelectric conversion element is formed of 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 electrically arranged in series via electrodes formed on both ends of the plurality of thermoelectric conversion elements.

[0021] The thermoelectric conversion module 1 is formed in a generally flat plate shape, more specifically, a generally rectangular plate shape in side view. The thermoelectric conversion module 1 has a first surface 11 and a second surface 12 that face opposite each other in a predetermined horizontal direction (i.e., the stacking direction). The multiple thermoelectric conversion elements are arranged two-dimensionally so that the high-temperature side electrodes face the first surface 11 and the low-temperature side electrodes face the second surface 12.

[0022] The thermoelectric conversion module 1 generates thermoelectric power in response 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. Both the first surface 11 and the second surface 12 are formed in a flat shape.

[0023] The power generation device 10 includes a plurality of (four in this example) thermoelectric conversion modules 1. The thermoelectric conversion modules 1 are arranged on both sides of the heating heat exchanger 3 in the stacking direction; more specifically, two thermoelectric conversion modules 1 are arranged on each side of the heating heat exchanger 3 in the stacking direction. Two thermoelectric conversion modules 1 arranged on the same side of the heating heat exchanger 3 are vertically arranged with a gap between them. The first surfaces 11 of the four thermoelectric conversion modules 1 face toward the heating heat exchanger 3. The second surfaces 12 of the two thermoelectric conversion modules 1 arranged on the first base 6A side of the heating heat exchanger 3 face toward the first cooling heat exchanger 4A, and the second surfaces 12 of the two thermoelectric conversion modules 1 arranged on the second base 6B side of the heating heat exchanger 3 face toward the second cooling heat exchanger 4B.

[0024] Hereinafter, for convenience of explanation, the stacking direction may be referred to as the “left-right direction,” the arrangement direction of the thermoelectric conversion modules 1 may be referred to as the “up-down direction,” and the direction perpendicular to both the left-right direction and the up-down direction may be referred to as the “front-back direction.” The front-back direction is an example of a specific direction perpendicular to both the horizontal direction and the up-down direction.

[0025] =Heating Heat Exchanger= The heating heat exchanger 3 is in contact with the first surface 11 of the thermoelectric conversion module 1 in the stacking direction and heats the first surface 11. Steam is supplied to the heating heat exchanger 3 as a heat source. The heating heat exchanger 3 exchanges heat between the steam and the first surface 11. In other words, the heating heat exchanger 3 heats the first surface 11 with steam. Steam is an example of a heating gas.

[0026] Specifically, the heating heat exchanger 3 has a container-shaped main body 30 to which steam is supplied, and an inlet port and an outlet port. The main body 30 is formed in a generally rectangular column shape extending in the longitudinal direction. The longitudinal direction of the main body 30 coincides with the vertical direction, i.e., the arrangement direction of the thermoelectric conversion modules 1. A first heating surface 32 and a second heating surface 33 are formed in a portion of the main body 30 as heating surfaces that contact the first surface 11. The heating heat exchanger 3 heats the first surface 11 via the first heating surface 32 and the second heating surface 33 with steam supplied to the main body 30. The first heating surface 32 and the second heating surface 33 are flat surfaces facing opposite each other in the stacking direction. The first heating surface 32 faces toward the first cooling heat exchanger 4A, and the second heating surface 33 faces toward the second cooling heat exchanger 4B.

[0027] Fig. 5 is a cross-sectional view of the heating heat exchanger 3 and the drain trap 9. In Fig. 5, dashed arrows indicate the flow of steam, and solid arrows indicate the flow of drain.

[0028] The inlet port and the outlet port are provided in the main body 30. In this example, a single inlet / outlet port that combines the inlet port and the outlet port is provided in the bottom wall 30a of the main body 30. Steam flows into the inlet / outlet port, and condensate (i.e., drainage) of the steam generated by heating the first surface 11 inside the main body 30 flows out of the inlet / outlet port.

[0029] Specifically, the heating heat exchanger 3 has a pipe fitting 31 connected to the bottom wall 30a of the main body 30. The pipe fitting 31 is a so-called T-shaped pipe fitting having three ports. More specifically, the pipe fitting 31 has a first port 31a, a second port 31b, and a third port 31c. The second port 31b is an example of an inlet / outlet port. In the pipe fitting 31, the first port 31a and the third port 31c face each other, and the second port 31b is connected to the bottom wall 30a and communicates with the inside of the main body 30. A steam inlet pipe 161 is connected to the first port 31a.

[0030] In the heating heat exchanger 3, steam that has flowed into the first port 31a from the inlet pipe 161 flows into the main body 30 from the second port 31b. The steam that has flowed into the main body 30 radiates heat to the first surface 11 of the thermoelectric conversion module 1 via the first heating surface 32 and the second heating surface 33, heating the first surface 11. The steam that has radiated heat to the first surface 11 condenses on the inner wall surfaces of the main body 30 that correspond to the first heating surface 32 and the second heating surface 33, becoming condensate. The condensate flows down the inner wall surfaces of the main body 30 and finally flows out from the second port 31b. In this way, in the main body 30 of the heating heat exchanger 3, steam flows in and condensate flows out in parallel through the single second port 31b.

[0031] The drain trap 9 is connected to the third port 31c of the pipe joint 31 via a connecting pipe 36. The drain that flows out from the second port 31b flows into the drain trap 9 via the outflow pipe 36. The drain trap 9 allows the drain to flow out when drain has flowed in, and prevents the outflow of steam when steam has flowed in.

[0032] 5, the drain trap 9 includes a casing 91 having a drain storage chamber 93, and a valve mechanism provided in the storage chamber 93. The casing 91 is formed with an inlet 92 and outlet 94 for drain, and a discharge passage 95. The inlet 92 communicates with the upper part of the storage chamber 93, and the discharge passage 95 is connected to the lower part of the storage chamber 93 and the outlet 94. The inlet 92 is connected to the connecting pipe 36.

[0033] The valve mechanism has a valve hole 96 formed in the storage chamber 93 and a valve element 97 that opens and closes the valve hole 96. The valve hole 96 connects the storage chamber 93 with the discharge passage 95. The valve element 97 is a float that is housed in the storage chamber 93. The valve element 97 opens and closes the valve hole 96 by rising and falling depending on the storage level of the drain in the storage chamber 93. When the valve hole 96 is opened, the drain flows out from the storage chamber 93 through the discharge passage 95 and the outlet 94, and when the valve hole 96 is closed, the outflow of the drain is stopped.

[0034] In this way, the drain trap 9 temporarily stores and then discharges the drain that flows out from the second port 31b of the heating heat exchanger 3. This can prevent the drain that flows out from the second port 31b from accumulating in the pipe joint 31 and the inflow pipe 161. This ensures an appropriate flow of steam from the inflow pipe 161 to the second port 31b, thereby more appropriately allowing steam to flow in and drain to flow out of the main body 30 of the heating heat exchanger 3.

[0035] The heating heat exchanger 3 further has a stand 38 to which the main body 30 is attached. Specifically, the main body 30 is provided with four screws 37 that are fastened to the stand 38. The four screws 37 extend downward from a bottom wall 30a that closes one end of the side peripheral wall of the main body 30. The main body 30 is fixed to the stand 38 by threading the screws 37 into screw holes formed in the stand 38. In this way, the heating heat exchanger 3 is fixedly installed. The power generation device 10 is placed on the floor or the like via the stand 38.

[0036] Furthermore, the heating heat exchanger 3 has an attachment portion 34 that is attached to the support 8. The attachment portion 34 is fixed to an upper wall that closes the other end of the side peripheral wall of the main body 30. A through hole 34a through which the support 8 is inserted is formed in the attachment portion 34. More specifically, two through holes 34a are formed in the attachment portion 21. The two through holes 34a are holes that penetrate in the stacking direction and are aligned with each other in the front-to-rear direction.

[0037] =Cooling Heat Exchanger= The cooling heat exchanger 4 is in contact with the second surface 12 of the thermoelectric conversion module 1 in the stacking direction and cools the second surface 12. Cooling water is supplied to the cooling heat exchanger 4 as a cooling source. The cooling heat exchanger 4 exchanges heat between the cooling water and the second surface 12. In other words, the cooling heat exchanger 4 cools the second surface 12 with the cooling water. The cooling water is an example of a cooling fluid.

[0038] Specifically, each of the first cooling heat exchanger 4A and the second cooling heat exchanger 4B has a container-shaped main body 40 to which cooling water is supplied, an inlet port 41, and an outlet port 42. The main body 40 is formed in a generally rectangular column shape extending in the longitudinal direction, more specifically, a generally rectangular parallelepiped shape extending in the longitudinal direction. The longitudinal direction of the main body 40 coincides with the up-down direction, i.e., the arrangement direction of the thermoelectric conversion modules 1. A planar cooling surface 43 that contacts the second surface 12 is formed in a portion of the main body 40. The first cooling heat exchanger 4A and the second cooling heat exchanger 4B cool the second surface 12 via the cooling surface 43 with the cooling water supplied to the main body 40.

[0039] The cooling surface 43 of the first cooling heat exchanger 4A and the cooling surface 43 of the second cooling heat exchanger 4B face each other in the stacking direction. The cooling surface 43 of the first cooling heat exchanger 4A faces the first heating surface 32, and the cooling surface 43 of the second cooling heat exchanger 4B faces the second heating surface 33. In other words, the first cooling heat exchanger 4A and the second cooling heat exchanger 4B are each arranged so that the cooling surface 43 faces the second surface 12 of the thermoelectric conversion module 1.

[0040] The inlet port 41 is provided at one longitudinal end of the main body 40, and the outlet port 42 is provided at the other longitudinal end of the main body 40. More specifically, the inlet port 41 is provided at the upper end of the side wall of the main body 40, and the outlet port 42 is provided at the lower end of the side wall of the main body 40.

[0041] Cooling water flows into the main body 40 through the inlet port 41. The cooling water that flows into the main body 40 flows through the main body 40 and flows out through the outlet port 42. While flowing through the main body 40, the cooling water exchanges heat with the thermoelectric conversion module 1. More specifically, the cooling water in the main body 40 absorbs heat from the second surface 12 of the thermoelectric conversion module 1 through the cooling surface 43. This cools the second surface 12.

[0042] Furthermore, each of the first cooling heat exchanger 4A and the second cooling heat exchanger 4B has an attachment portion 44 that is attached to the support 8. The attachment portion 44 is fixed to the upper wall of the main body 40. The attachment portion 44 has a through hole 44a formed therein, through which the support 8 is inserted. More specifically, the attachment portion 44 has two pairs of coaxial through holes 44a that penetrate in the stacking direction, lined up in the front-to-rear direction. In this way, the first cooling heat exchanger 4A and the second cooling heat exchanger 4B are supported by the support 8 by attaching the attachment portions 44 to the support 8. More specifically, the first cooling heat exchanger 4A and the second cooling heat exchanger 4B are supported by the support 8 so as to be displaceable in the stacking direction relative to the heating heat exchanger 3.

[0043] =Positioner= The positioner 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 4. More specifically, the positioner 2 has the function of determining the positions of the multiple thermoelectric conversion modules 1 and the function of insulating the multiple thermoelectric conversion modules 1 from each other. In other words, the positioner 2 positions the thermoelectric conversion module 1 at a position where it appropriately contacts the first heating surface 32 or the second heating surface 33 and the cooling surface 43, while insulating two adjacent thermoelectric conversion modules 1 from each other.

[0044] Specifically, the positioning device 2 has a frame 20. The frame 20 has a shape that partially follows the overall outline of the two thermoelectric conversion modules 1 in a plane that is approximately parallel to the first surface 11 or the second surface 12. The frame 20 has a spacer 22 that is disposed between the two adjacent thermoelectric conversion modules 1. The spacer 22 separates the two adjacent thermoelectric conversion modules 1 from each other. In this example, the positioning device 2 is formed of a heat insulating material. The thickness of the frame 20 (i.e., the dimension in the stacking direction) is thinner than the thickness of the thermoelectric conversion modules 1 (i.e., the dimension in the stacking direction).

[0045] Furthermore, the positioning device 2 has mounting portions 21 that are attached to the support 8. In this example, the positioning device 2 has two mounting portions 21. The two mounting portions 21 are integrally formed with the frame 20. The two mounting portions 21 are protruding pieces that protrude upward from the upper end of the frame 20. The two mounting portions 21 are aligned with each other in the front-to-rear direction. A through hole 21a is formed in the mounting portion 21, through which the support 8 is inserted. In this way, the positioning device 2 is supported by the support 8 by attaching the mounting portions 21 to the support 8. More specifically, the positioning device 2 is supported by the support 8 so as to be displaceable in the stacking direction relative to the heating heat exchanger 3.

[0046] =Base= The first base 6A and the second base 6B sandwich the thermoelectric conversion module 1, the heating heat exchanger 3, the first cooling heat exchanger 4A, the second cooling heat exchanger 4B, and the pressing device 5. The first base 6A and the second base 6B are connected to each other by a connector 7, thereby sandwiching the thermoelectric conversion module 1 and the like. Specifically, each of the first base 6A and the second base 6B has a plate-shaped main body 60 and a bent portion 61 provided on an edge portion of the main body 60.

[0047] The main body 60 is formed in a generally rectangular shape in a side view, with the longitudinal direction coinciding with the up-down direction. The main body 60 of the first base 6A and the main body 60 of the second base 6B extend in a plane generally perpendicular to the stacking direction and are generally parallel to each other. The bent portion 61 is integrally formed at the upper edge of the main body 60. The bent portion 61 of the first base 6A and the bent portion 61 of the second base 6B are bent in opposite directions in the stacking direction, more specifically, bent so as to face each other.

[0048] The pair of bases 6 further include guides 65 that restrict displacement of the cooling heat exchanger 4, more specifically, displacement of the second cooling heat exchanger 4B. Specifically, the guides 65 restrict displacement of the second cooling heat exchanger 4B in the front-to-rear direction while allowing displacement of the second cooling heat exchanger 4B in the stacking direction. In this example, the pair of bases 6 include four guides 65.

[0049] Four guides 65 are provided on the main body 60 of the second base 6B. The guides 65 are formed in a cylindrical shape extending in the stacking direction from the inner surface of the main body 60 toward the second cooling heat exchanger 4B. Two guides 65 are arranged on each outer side in the front-to-rear direction of the main body 40 of the second cooling heat exchanger 4B. More specifically, the guides 65 are in contact with two side walls of the main body 40 that face each other in the front-to-rear direction. In this way, by arranging the guides 65 so as to be in contact with both ends of the main body 40 in the front-to-rear direction, displacement of the second cooling heat exchanger 4B in the front-to-rear direction is restricted.

[0050] A top plate 67 is attached to the bending portion 61. The top plate 67 is formed in a flat plate shape that extends in a plane perpendicular to the up-down direction. A handle 68 is provided on the top plate 67. The top plate 67 is attached to the bending portion 61 with multiple (four in this example) screws 67b. The screws 67b are inserted into through holes 67a formed in the top plate 67 and through holes 61a formed in the bending portion 61. The through holes 61a in the bending portion 61 are circular and have approximately the same diameter as the screws 67b, and the through holes 67a in the top plate 67 are elongated holes that are long in the stacking direction. In other words, relative displacement of the pair of bases 6 with respect to the top plate 67 in the stacking direction is permitted.

[0051] =Coupler= The coupler 7 connects the first base 6A and the second base 6B, thereby sandwiching the heating heat exchanger 3 and the like between the first base 6A and the second base 6B. More specifically, the coupler 7 connects the first base 6A and the second base 6B while maintaining a constant distance between the pair of bases 6 in the stacking direction (hereinafter also referred to as the sandwiching distance). The pair of bases 6 are integrally formed by being connected by the coupler 7. In this example, the power generation device 10 includes four couplers 7.

[0052] The coupler 7 has a shaft 71 and a spacer 72. The shaft 71 is formed in a rod shape extending in the stacking direction, and both ends thereof are connected to the main body 60 of the first base 6A and the main body 60 of the second base 6B. Male threads are formed at both ends of the shaft 71. Four through holes 60a are formed in the main body 60 of each of the first base 6A and the second base 6B, through which the ends of the shafts 71 of the four couplers 7 are inserted. Both ends of the shaft 71 are fastened with nuts from the outside of the first base 6A and the second base 6B.

[0053] The spacers 72 maintain a constant sandwiching distance between the pair of bases 6. The spacers 72 are formed in a tubular shape, more specifically, a cylindrical shape, through which the shaft 71 is inserted. The spacers 72 of each of the four couplers 7 are disposed between the main body 60 of the first base 6A and the main body 60 of the second base 6B, with the shaft 71 inserted therethrough. In this way, by disposing the spacers 72 between the first base 6A and the second base 6B, the sandwiching distance is maintained constant.

[0054] =Presser= The presser 5 has a spring 51 that urges the cooling heat exchanger 4 toward the heating heat exchanger 3, and a support 52 that supports the spring 51. The presser 5 presses the cooling heat exchanger 4 in the stacking direction by the elastic force of the spring 51. The presser 5 elastically presses one of the first cooling heat exchanger 4A and the second cooling heat exchanger 4B, in this example, the second cooling heat exchanger 4B, toward the heating heat exchanger 3 by the spring 51.

[0055] More specifically, the pressing device 5 has a plurality of springs 51. In this example, the pressing device 5 has four springs 51. The springs 51 are arranged between the second cooling heat exchanger 4B and the second base 6B, more specifically, between the main body 40 of the second cooling heat exchanger 4B and the main body 60 of the second base 6B. The springs 51 have elasticity in the stacking direction and can expand and contract in the stacking direction. In this example, the springs 51 are coil springs. The four springs 51 are attached to the second base 6B via supports 52.

[0056] The pressing device 5 has the same number of supports 52 as the number of springs 51 (i.e., four). The four supports 52 are attached to the main body 60 of the second base 6B. The supports 52 are shafts, more specifically, screws, that penetrate the main body 60 in the stacking direction. The supports 52 are inserted into screw holes formed in the main body 60 from the outside in the stacking direction of the main body 60. In other words, the supports 52 protrude from the inner surface of the main body 60 in the stacking direction. The portions of the supports 52 that protrude from the inner surface of the main body 60 are inserted into the springs 51. In this way, the springs 51 are attached to the main body 60 via the supports 52 by being fitted onto the supports 52, i.e., by being disposed on the outer periphery of the supports 52.

[0057] The springs 51 are arranged in a compressed and deformed state. The base ends of the springs 51, i.e., the ends of the springs 51 on the second base 6B side, are in contact with the main body 60. The tip ends of the springs 51, i.e., the ends of the springs 51 on the second cooling heat exchanger 4B side, are in contact with the main body 40. In this way, the four springs 51 elastically urge the second cooling heat exchanger 4B toward the heating heat exchanger 3. The four springs 51 are arranged so that the elastic force acts evenly over the entire main body 40.

[0058] Pressing the second cooling heat exchanger 4B by the presser 5 in this manner maintains appropriate contact between the cooling surface 43 of the second cooling heat exchanger 4B and the second surface 12 of the thermoelectric conversion module 1, and between the first surface 11 of the thermoelectric conversion module 1 and the second heating surface 33 of 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 second cooling heat exchanger 4B.

[0059] A first contact plate 55 is disposed between the first heating surface 32 and the first surface 11 and between the second heating surface 33 and the first surface 11. A second contact plate 56 is disposed between the cooling surface 43 and the second surface 12 of the first cooling heat exchanger 4A and between the cooling surface 43 and the second surface 12 of the second cooling heat exchanger 4B. The first contact plate 55 and the second contact plate 56 are formed as flat plates extending in a plane perpendicular to the stacking direction. In other words, the first heating surface 32 and the second heating surface 33 are in contact with the first surface 11 via the first contact plate 55, and the cooling surface 43 is in contact with the second surface 12 via the second contact plate 56.

[0060] =Support= The support 8 supports the cooling heat exchanger 4 and the positioning device 2 so that they can be displaced in the stacking direction but not in the up-down direction. The support 8 has two shafts 81 and a first slider 82 and a second slider 83 attached to each shaft 81. The support 8 suspends the cooling heat exchanger 4 and the positioning device 2 from the shaft 81 via the first slider 82 and the second slider 83.

[0061] The two shafts 81 extend in the stacking direction and are parallel to each other. The two shafts 81 are aligned in the front-to-rear direction. The two shafts 81 are connected to the main bodies 60 of the first base 6A and the second base 6B. The two shafts 81 are disposed above the main body 30 of the heating heat exchanger 3 and the main body 40 of the cooling heat exchanger 4. The two shafts 81 are inserted into the through-holes 34a of the mounting portion 34 so as to be displaceable in the stacking direction.

[0062] The first slider 82 and the second slider 83 are formed in a cylindrical shape through which the shaft 81 is inserted. Hereinafter, when the first slider 82 and the second slider 83 are collectively referred to, they will be referred to as sliders 82, 83. The sliders 82, 83 are positioned between the first base 6A and the second base 6B with the shaft 81 inserted therethrough. The sliders 82, 83 are arranged to be slidable in the stacking direction relative to the shaft 81. The sliders 82, 83 have an inner diameter that is approximately the same as the outer diameter of the shaft 81, and their displacement in the vertical direction is substantially restricted by the shaft 81.

[0063] The first slider 82 is inserted through the through-hole 44a of the first cooling heat exchanger 4A and the through-hole 21a of the positioning device 2, and the second slider 83 is inserted through the through-hole 44a of the second cooling heat exchanger 4B and the through-hole 21a of the positioning device 2. In this way, the cooling heat exchangers 4 and the positioning device 2 are fixed to the sliders 82, 83 of each shaft 81 and suspended from the shaft 81 so as to be displaceable in the stacking direction but not displaceable in the up-down direction.

[0064] 6 is an enlarged cross-sectional view of the shaft 81 and sliders 82, 83 of the support 8. The shaft 81 has a male screw formed in the area where the sliders 82, 83 slide. The threads 81a of the male screw of the shaft 81 contact the inner circumferential surface 82a of the first slider 82 and the inner circumferential surface 83a of the second slider 83 over the entire circumference. In this example, the shaft 81 is made of metal, and the first slider 82 and the second slider 83 are made of resin.

[0065] =Details of Base and Coupler= Next, the configuration of the pair of bases 6 and couplers 7 will be described in more detail.

[0066] The pair of bases 6 are arranged so as to be displaceable in the stacking direction. That is, the pair of bases 6 formed integrally by the connector 7 are displaceable in the stacking direction relative to the fixed heating heat exchanger 3. In other words, the first base 6A and the second base 6B can be displaced in the same direction in the stacking direction while maintaining a sandwiching gap. Therefore, by simply providing the presser 5 only on one of the two cooling heat exchangers 4, in this example, only on the second cooling heat exchanger 4B side, both of the two cooling heat exchangers 4 can be supported so as to be elastically displaceable in the stacking direction.

[0067] Specifically, the spring 51 is disposed only between the first cooling heat exchanger 4A and the first base 6A and between the second cooling heat exchanger 4B and the second base 6B. The elastic force of the spring 51 acts directly on the second cooling heat exchanger 4B. That is, the second cooling heat exchanger 4B is elastically pressed directly in the stacking direction by the pressing device 5. On the other hand, the elastic force of the spring 51 acts on the first cooling heat exchanger 4A via the second base 6B, the connector 7, and the first base 6A. That is, the first cooling heat exchanger 4A is elastically pressed indirectly in the stacking direction by the pressing device 5. In this way, the first cooling heat exchanger 4A and the second cooling heat exchanger 4B can be elastically displaced in the stacking direction.

[0068] This configuration not only properly maintains contact between the cooling surface 43 of the second cooling heat exchanger 4B and the second surface 12 of the thermoelectric conversion module 1 and between the first surface 11 of the thermoelectric conversion module 1 and the second heating surface 33 of the heating heat exchanger 3, but also properly maintains contact between the cooling surface 43 of the first cooling heat exchanger 4A and the second surface 12 of the thermoelectric conversion module 1 and between the first surface 11 of the thermoelectric conversion module 1 and the first heating surface 32 of the heating heat exchanger 3. As a result, the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3, the first cooling heat exchanger 4A, and the second cooling heat exchanger 4B is improved. This eliminates the need for a spring on the other cooling heat exchanger 4 side, leading to a more compact and cost-effective device.

[0069] The connectors 7 suppress deviation in the relative position of the pair of bases 6 with respect to the heating heat exchanger 3, the cooling heat exchanger 4, etc. in the front-to-rear direction. Specifically, the connectors 7 are disposed on both sides of the heating heat exchanger 3 and the cooling heat exchanger 4 in the front-to-rear direction. The connectors 7 contact both ends of at least one of the heating heat exchanger 3 and the cooling heat exchanger 4 in the front-to-rear direction.

[0070] In this example, each connector 7 contacts both ends of the heating heat exchanger 3 in the front-to-rear direction of the heating heat exchanger 3 out of the heating heat exchanger 3 and the cooling heat exchanger 4. As shown in Fig. 4 , the main body 30 of the heating heat exchanger 3 protrudes further on both sides in the front-to-rear direction than the main body 40 of the cooling heat exchanger 4. Therefore, each connector 7 is disposed so as to contact both ends of the main body 30 of the heating heat exchanger 3 in the front-to-rear direction.

[0071] Specifically, two couplers 7 are arranged on each side in the front-to-rear direction of the main body 30 of the heating heat exchanger 3. On both sides in the front-to-rear direction of the main body 30, the two couplers 7 are lined up in the up-and-down direction. More specifically, the couplers 7 are arranged so that the spacers 72 contact both ends in the front-to-rear direction of the main body 30 (more specifically, the side peripheral walls of the main body 30). Because the spacers 72 are formed in a cylindrical shape, the spacers 72 and the main body 30 are in point contact or line contact.

[0072] In this way, the connectors 7 contact both ends of the heating heat exchanger 3 in the front-rear direction, thereby restricting the front-rear displacement of the pair of bases 6 by the connectors 7. In other words, the pair of bases 6 cannot be displaced in the front-rear direction relative to the fixedly installed heating heat exchanger 3. Therefore, deviation in the relative position of the pair of bases 6 with respect to the heating heat exchanger 3, the cooling heat exchanger 4, etc. in the front-rear direction is suppressed. As a result, the heating heat exchanger 3, the cooling heat exchanger 4, etc. are properly sandwiched between the pair of bases 6.

[0073] =Operation of the Power Generator= Next, the operation of the power generator 10 will be described.

[0074] In the heating heat exchanger 3, steam flows into the main body 30 from the inlet pipe 161 via the second port 31b. The steam remains in the main body 30. Meanwhile, in the cooling heat exchanger 4, cooling water flows into the main body 40 from the inlet port 41. The cooling water flows through the main body 40.

[0075] The first surface 11 of the thermoelectric conversion module 1 is in contact with the first heating surface 32 and the second heating surface 33 of the heating heat exchanger 3 via the first contact plate 55, and is therefore heated by steam in the main body 30 via the first heating surface 32 and the second heating surface 33. Meanwhile, the second surface 12 of the thermoelectric conversion module 1 is in contact with the cooling surface 43 of the cooling heat exchanger 4 via the second contact plate 56, and is therefore cooled by the cooling water in the main body 40 via the cooling surface 43. This creates a temperature difference between the first surface 11 and the second surface 12 of the thermoelectric conversion module 1, and the thermoelectric conversion module 1 generates electricity in accordance with the temperature difference. In this way, the power generation device 10 generates electricity by utilizing the thermal energy of the steam.

[0076] In the heating heat exchanger 3, steam that flows into the main body 30 radiates heat to the first surface 11 on the inner wall surfaces of the main body 30 corresponding to the first heating surface 32 and the second heating surface 33, condenses, and becomes drainage. Here, the first surface 11 is approximately perpendicular to the horizontal direction (i.e., the stacking direction), so the heating surfaces in contact with the first surface 11 and the corresponding inner wall surfaces are also approximately perpendicular to the horizontal direction. Therefore, the drainage flows down the inner wall surfaces of the main body 30 due to its own weight. Because the drainage flows down the inner wall surfaces and separates from the first heating surface 32 and the second heating surface 33, the drainage does not inhibit the heat radiation of the steam to the first surface 11 via the first heating surface 32 and the second heating surface 33. The drainage that flows down the inner wall surfaces of the main body 30 flows down to the bottom wall 30a and finally flows out from the second port 31b.

[0077] In this way, the drain generated inside the main body 30 naturally and smoothly flows out from the second port 31b located at the bottom of the main body 30. Steam flows into the main body 30 from the second port 31b in an amount corresponding to the amount of drain that flows out from the second port 31b. In this way, the inflow of steam and the outflow of drain occur in parallel through the single second port 31b.

[0078] The drain that flows out from the second port 31b flows into the drain trap 9 via the connecting pipe 36. Here, because the drain trap 9 has a storage chamber 93, the drain that flows out from the second port 31b is stored in the drain trap 9 without accumulating in the pipe joint 31 or the inflow pipe 161. This ensures an appropriate flow of steam from the inflow pipe 161 to the second port 31b, so that the inflow of steam and the outflow of drain in the heating heat exchanger 3 are more appropriate.

[0079] Meanwhile, in the cooling heat exchanger 4, the cooling water that flows into the main body 40 from the inlet port 41 absorbs heat from the second surface 12 of the thermoelectric conversion module 1 via the cooling surface 43. The cooling water is heated while flowing through the main body 40 and flows out from the outlet port 42. Here, since the inlet port 41 is located at the upper end of the main body 40 and the outlet port 42 is located at the lower end of the main body 40, the cooling water flows smoothly from top to bottom within the main body 40. In other words, the cooling water, which is a heat medium, flows smoothly through the cooling surface 43 and the second surface 12. This improves the cooling efficiency of the cooling heat exchanger 4.

[0080] =Displacement Operation of Cooling Heat Exchanger, etc.= Next, the displacement operation of the cooling heat exchanger 4, etc. will be described. Fig. 7 is a diagram schematically showing the displacement of the cooling heat exchanger 4, etc. Note that the first contact plate 55 and the second contact plate 56 are omitted in Fig. 7.

[0081] In the heating heat exchanger 3, the main body 30 may expand due to the heat and pressure of the steam. In this example, a case where the main body 30 expands and deforms in both directions in the stacking direction will be described. Here, the cooling heat exchanger 4 and the thermoelectric conversion module 1 are supported so as to be elastically displaceable in the stacking direction relative to the heating heat exchanger 3. More specifically, of the two cooling heat exchangers 4, the second cooling heat exchanger 4B is elastically pressed by a pressing device 5 toward the heating heat exchanger 3 in the stacking direction. The pair of bases 6 are formed integrally with each other and are disposed so as to be displaceable in the stacking direction.

[0082] Therefore, the first cooling heat exchanger 4A, the adjacent thermoelectric conversion module 1, and the positioning device 2 are displaced in the direction of arrow X1 in the stacking direction in response to the expansion and deformation of the main body 30. Accordingly, the pair of bases 6 are displaced in the direction of arrow X3 in the stacking direction, i.e., in the same direction as the first cooling heat exchanger 4A, while maintaining the clamping distance D. Furthermore, the first slider 82, together with the first cooling heat exchanger 4A and the positioning device 2, is displaced in the direction of arrow X4 in the stacking direction, i.e., in the same direction as the first cooling heat exchanger 4A. In other words, the first slider 82 is displaced in the direction of arrow X4 together with the shaft 81.

[0083] Meanwhile, the second cooling heat exchanger 4B, the adjacent thermoelectric conversion module 1, and the positioning device 2 are displaced in the direction of arrow X2 in the stacking direction, i.e., in the direction opposite to the pair of bases 6, in response to the expansion and deformation of the main body 30. Accordingly, the second slider 83, together with the second cooling heat exchanger 4B and the positioning device 2, is displaced in the direction of arrow X5 in the stacking direction, i.e., in the same direction as the pair of bases 6. In other words, the second slider 83 slides relative to the shaft 81 in the direction of arrow X5. These displacements cause the spring 53 to shorten. In this way, the spring 51 of the pressing device 5 directly absorbs the displacement of the second cooling heat exchanger 4B and the like, and also absorbs the displacement of the first cooling heat exchanger 4A and the like via the pair of bases 6.

[0084] In this way, the thermoelectric conversion module 1 and the cooling heat exchanger 4 follow the expansion and deformation of the heating heat exchanger 3. This reduces damage to the thermoelectric conversion module 1 due to compression between the heating heat exchanger 3 and the cooling heat exchanger 4, and also maintains appropriate contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4. By maintaining appropriate contact between the thermoelectric conversion module 1 and the like, the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4 is improved.

[0085] At this time, because the connector 7 is in contact with the heating heat exchanger 3, the connector 7 restricts the displacement of the pair of bases 6 in the front-to-rear direction. Therefore, deviation in the relative position of the pair of bases 6 with respect to the heating heat exchanger 3, the cooling heat exchanger 4, etc. in the front-to-rear direction is suppressed. This allows the heating heat exchanger 3, the cooling heat exchanger 4, etc. to be properly sandwiched between the pair of bases 6. As a result, contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4 is properly maintained, thereby improving the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4.

[0086] Furthermore, since the cylindrical spacer 72 and the main body 30 of the heating heat exchanger 3 are in point contact or line contact, the frictional resistance between the connector 7 and the heating heat exchanger 3 is reduced compared to when they are in surface contact. This allows the pair of bases 6 to move smoothly in the stacking direction.

[0087] Furthermore, because the vertical displacement of the cooling heat exchanger 4 and the positioning device 2 is restricted by the support 8, misalignment of the thermoelectric conversion module 1, the heating heat exchanger 3, and the cooling heat exchanger 4 relative to one another in the in-plane direction of the first surface 11 and the second surface 12 is suppressed. As a result, contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4 is appropriately maintained.

[0088] Furthermore, because the cooling heat exchanger 4 and the positioning device 2 are each suspended from two shafts 81, rotational displacement around an axis extending in the stacking direction is restricted. That is, if the cooling heat exchanger 4, etc. were suspended from a single shaft, there would be a risk that the cooling heat exchanger 4, etc. would rotate around the axis of that shaft, but in this example, such rotational displacement of the cooling heat exchanger 4, etc. is prevented. In this way, by restricting the rotational displacement of the cooling heat exchanger 4 and the positioning device 2, relative positional deviation between the thermoelectric conversion module 1, the heating heat exchanger 3, and the cooling heat exchanger 4 in the in-plane direction of the first surface 11 and the second surface 12 is further suppressed.

[0089] Furthermore, because male threads are formed in the sliding regions of the sliders 82 and 83 on the shaft 81, the contact area between the shaft 81 and the sliders 82 and 83 is reduced. This reduces frictional resistance between the shaft 81 and the sliders 82 and 83. Furthermore, because the shaft 81 is made of metal and the sliders 82 and 83 are made of resin, frictional resistance between the shaft 81 and the sliders 82 and 83 is reduced compared to, for example, when both are made of metal. This reduction in frictional resistance improves the smoothness of the sliding movement of the sliders 82 and 83 relative to the shaft 81. This smooths the displacement movement of the cooling heat exchanger 4 and the positioning device 2 in the stacking direction, thereby maintaining appropriate contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4.

[0090] =Drain Recovery System= Next, an application example of the power generation device 10 will be described. The power generation device 10 is incorporated into a drain recovery system 100. FIG. 8 is a piping diagram showing a schematic configuration of the drain recovery system 100.

[0091] The drain recovery system 100 recovers drain generated by condensation of steam and recovers heat from flash steam (including steam) generated from the drain. The drain recovery system 100 is an example of a steam system.

[0092] The drain recovery system 100 includes steam-using equipment that receives a supply of steam 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 incoming drain and steam into drain and steam, a heat recovery device 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 the power generation device 10. The drain recovery system 100 further includes a header tank 120 that stores drain. The liquid pumping device 150 is an example of a pump and an example of steam-using equipment.

[0093] The gas-liquid separator 110 separates the mixed fluid of the incoming condensate and its flash steam into condensate and steam. An inlet pipe 112, a liquid pipe 113, and a gas pipe 114 are connected to the gas-liquid separator 110. The inlet pipe 112 carries condensate and its flash steam generated in steam-using equipment (not shown) outside the condensate recovery system 100. The condensate and steam flow into the gas-liquid separator 110 via the inlet pipe 112.

[0094] The gas-liquid separator 110 discharges the separated drain from a liquid pipe 113. The liquid pipe 113 is connected to a 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 from a gas pipe 114. The gas pipe 114 is connected to a heat recovery unit 140. The steam is supplied to the heat recovery unit 140 via the gas pipe 114.

[0095] The header tank 120 stores the 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.

[0096] 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 that stores drain, and the upper part of the internal space is a storage section 124 that stores 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 also stores flash steam generated from the drain in the storage section 124.

[0097] An overflow pipe 125 is connected to the tank body 121. The overflow pipe 125 passes through the tank body 121. One end of the overflow pipe 125 is disposed in the storage section 123, and the other end of the overflow pipe 125 is disposed outside the tank body 121. When the amount of drainage stored in the storage section 123 of the tank body 121 increases to or exceeds a certain amount, the excess drainage flows out of the tank body 121 via the overflow pipe 125.

[0098] The water seal trap 126 stores seal water. Under normal circumstances, the water seal trap 126 prevents steam from leaking out of the tank body 121 by using a water seal, but in an emergency where the tank body 121 becomes abnormally high pressure, the water seal is broken and the steam in the tank body 121 is released into the atmosphere. The internal space of the tank body 121 is sealed by the water seal of the water seal trap 126.

[0099] 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 seal 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 disposed within 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 seal water increases. The outflowing condensate is supplied to the tank body 121 via the outlet pipe 128.

[0100] The heat recovery device 140 is a heat exchanger. The heat recovery device 140 has a first flow path 141 and a second flow path 142. The heat recovery device 140 exchanges heat between a fluid flowing through the first flow path 141 and a fluid flowing through the second flow path 142. A gas pipe 114 is connected to the upstream end of the first flow path 141. That is, steam from the gas-liquid separator 110 flows into the first flow path 141. A downstream end of the first flow path 141 is connected to the tank body 121 via an outlet pipe 144. A downstream end of the outlet pipe 144 is connected to the upper part of the tank body 121 and communicates with the retention section 124. A water supply pipe 145 that supplies water is connected to the upstream end of the second flow path 142. Cooling water flows through the water supply pipe 145. An outlet pipe 146 through which water flows out is connected to the downstream end of the second flow path 142.

[0101] In the heat recovery unit 140, steam supplied from the gas-liquid separator 110 flows into the first flow path 141 and circulates through the first flow path 141. Meanwhile, cooling water is supplied to the second flow path 142 from a water supply pipe 145, and the cooling water circulates through the first flow path 141. Heat exchange occurs between the steam circulating through the first flow path 141 and the cooling water circulating through the second flow path 142. The steam is cooled and condensed, and the cooling water is heated. Drain flows from the first flow path 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 flow path 142 to the outlet pipe 146. In this way, the heat recovery unit 140 recovers heat from the steam using water. The water heated by recovering the heat is supplied to a desired location or device through the outlet pipe 146.

[0102] The liquid pressure-feeding device 150 uses the supplied steam to pressure-feed the drain. The liquid pressure-feeding device 150 supplies the drain from the header tank 120 to a predetermined drain usage location. The liquid pressure-feeding device 150 alternately performs an inflow operation, in which the drain is introduced and stored, and a pressure-feed operation, in which the drain is pressure-fed. The liquid pressure-feeding device 150 has a casing 151, which is a sealed container, a valve device 152, and a float 153.

[0103] An inlet pipe 154 through which drain flows in and an outlet pipe 155 through which drain flows out are connected to the casing 151. The upstream end of the inlet pipe 154 is connected to the header tank 120. 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 provided with a check valve 156 that allows only flow from the header tank 120 to the casing 151. The outlet pipe 155 is connected to a relatively lower part of the casing 151, specifically, at least below the connection port of the inlet pipe 154. The downstream end of the outlet pipe 155 is connected to a location where the drain is used. The outlet pipe 155 is provided with a check valve 157 that allows only flow in the direction out of the casing 151. Specifically, the check valve 157 is closed by an elastic member such as a spring and opens when a pressure equal to or greater than a predetermined valve opening pressure is applied.

[0104] The internal space of the casing 151 serves as a storage space for drain. A float 153 is disposed in 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 rotation axis. The float 153 floats on the drain inside the casing 151. The float 153 moves up and down depending on the amount of drain stored inside the casing 151. At this time, the lever 153a rotates around the rotation axis in accordance with the up and down movement of the float 153.

[0105] A supply pipe 158 that supplies steam as a working gas and a discharge pipe 159 that discharges the steam from the casing 151 are connected to the casing 151. High-pressure steam flows through the supply pipe 158. A downstream end of the supply pipe 158 is connected to the valve device 152. An upstream end of the discharge pipe 159 is connected to the valve device 152. A downstream end of the discharge pipe 159 is connected to the header tank 120.

[0106] Although not shown, the valve device 152 includes an intake valve and an exhaust valve. The intake valve is provided at the downstream end of the supply pipe 158. The intake valve switches the supply pipe 158 between open and closed states. The exhaust valve is provided at the upstream end of the exhaust pipe 159. The exhaust valve switches the exhaust pipe 159 between open and closed states. The valve device 152 also has a switching mechanism that switches the intake valve and exhaust valve between open and closed states. The switching mechanism switches between an intake state in which the intake valve is open and the exhaust valve is closed, and an exhaust state in which the 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 to switch between the intake state and the exhaust state.

[0107] Specifically, when the float 153 is located at a relatively low position within the casing 151, the switching mechanism is in an 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 supply state. When the float 153 is in the supply state of the switching mechanism, the lever 153a switches the switching mechanism from the supply state to the exhaust state when the float 153 descends to a second switching position that is lower than the first switching position.

[0108] In the liquid pumping device 150 configured as described above, when the switching mechanism is in the exhaust state, the supply pipe 158 is blocked and the discharge pipe 159 is open. The float 153 is located at a relatively low position within the casing 151. In this state, the pressure within the header tank 120 causes drainage from the header tank 120 to flow into the casing 151 via the inlet pipe 154. When the differential pressure between the inlet pressure and the 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 drainage accumulates in the casing 151. As the drainage flows into the casing 151, steam within the casing 151 flows out to the discharge pipe 159 via the exhaust valve. The steam that has flowed out to the discharge pipe 159 flows into the header tank 120. In this manner, the liquid pumping device 150 performs an inflow operation.

[0109] During the inflow operation, the float 153 rises as the amount of accumulated drain increases. As the float 153 rises, the lever 153a rotates around the rotation axis. When the float 153 rises to the first switching position, the lever 153a switches the switching mechanism of the valve device 152 from the exhaust state to the supply state. The supply pipe 158 is opened, and the discharge pipe 159 is blocked. As a result, the liquid pressure-feeding device 150 switches from the inflow operation to the pressure-feeding operation.

[0110] In the pumping operation, steam is supplied into the casing 151 through 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 through the inflow pipe 154 and preventing backflow of steam from the casing 151 to the header tank 120 through the inflow pipe 154. When the differential pressure between the inlet pressure and the back pressure acting on the check valve 157 exceeds the opening pressure of the check valve 157, the check valve 157 opens, causing the condensate inside the casing 151 to flow out to the outflow pipe 155. The condensate is supplied through the outflow pipe 155 to a location where the condensate is used.

[0111] During the pumping operation, the inflow of condensate from the inflow pipe 154 stops, so the amount of condensate stored decreases. As the amount of condensate stored decreases, the float 153 descends. As the float 153 descends, the lever 153a rotates around the rotation 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 air supply state to the exhaust state. The supply pipe 158 is blocked, and the discharge pipe 159 is opened. In this way, the liquid pumping device 150 switches from the pumping operation to the inflow operation. Eventually, when the pressure inside the casing 151 decreases, the check valve 156 opens, and the inflow of condensate from the inflow pipe 154 begins.

[0112] In this way, the liquid pumping device 150 uses steam as a driving source to supply the drain of the header tank 120 to the drain usage location.

[0113] The power generation device 10 is supplied with steam before being supplied to the liquid pumping device 150 , and is also supplied with cooling water before being supplied to the heat recovery device 140 .

[0114] Specifically, an inlet pipe 161 branching from the supply pipe 158 is connected to the heating heat exchanger 3 (more specifically, the first port 31a of the pipe joint 31). An outlet pipe 162 for condensate is connected to the drain trap 9. The downstream end of the outlet pipe 162 is connected to the gas pipe 114. Steam circulating through the supply pipe 158 flows into the heating heat exchanger 3 via the inlet pipe 161. The condensate that has flowed out from the heating heat exchanger 3 flows into the gas pipe 114 via the drain trap 9 and the outlet pipe 162. It should be noted 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.

[0115] Meanwhile, an inlet pipe 163 branching from the water supply pipe 145 is connected to the inlet ports 41 of the two cooling heat exchangers 4. An outlet pipe 164 is connected to the outlet ports 42 of the two cooling heat exchangers 4. The downstream end of the outlet pipe 164 is connected to a part of the water supply pipe 145 downstream of the branching point of the inlet pipe 163. Water circulating through the water supply pipe 145 flows into the cooling heat exchanger 4 via the inlet pipe 163. The water flowing out of the cooling heat exchanger 4 returns to the water supply pipe 145 via the outlet pipe 164.

[0116] In this way, steam is supplied to the heating heat exchanger 3 and water is supplied to the two cooling heat exchangers 4, thereby heating the first surface 11 of the thermoelectric conversion module 1 and cooling the second surface 12. In this way, thermoelectric power generation is performed in the power generation device 10.

[0117] In this way, the drain recovery system 100 recovers the drain and supplies the recovered drain to a point where the drain is used by the liquid pumping device 150. Furthermore, the drain recovery system 100 recovers heat from flash steam generated from the drain by cooling water via the heat recovery device 140. The power generation device 10 generates power 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 power generation by utilizing the cooling water used in the drain recovery system 100, specifically the cooling water used in the heat recovery device 140.

[0118] In a steam system such as the condensate recovery system 100, there may be a surplus of thermal energy in the steam. In such a case, the thermal energy of the steam used in the condensate recovery system 100 can be effectively utilized for power generation. Furthermore, the power generation device 10 can function as a local power source. Therefore, for example, a power source can be secured without installing a power source or laying electric wires from the power source.

[0119] Furthermore, some of the steam may condense and generate drain in the inflow pipe 161. In this case, the drain generated in the inflow pipe 161 does not flow into the main body 30 of the heating heat exchanger 3, but flows into the drain trap 9 via the connecting pipe 36 and is stored therein. In this way, since the flow of drain into the main body 30 of the heating heat exchanger 3 is prevented, a decrease in the heat exchange amount in the heating heat exchanger 3, i.e., a decrease in the amount of heating by the heating heat exchanger 3, can be suppressed.

[0120] As described above, the power generation device 10 includes the thermoelectric conversion module 1, the fixed heating heat exchanger 3, two movable cooling heat exchangers 4, a presser 5, and a pair of bases 6. The thermoelectric conversion module 1 has a first surface 11 and a second surface 12 that face opposite each other in the stacking direction (i.e., a predetermined horizontal direction), and generates thermoelectric power in response to the temperature difference between the first surface 11 and the second surface 12. The heating heat exchangers 3 are arranged on both sides of the thermoelectric conversion modules 1 in the stacking direction and are in contact with the first surface 11 to heat the first surface 11. The two cooling heat exchangers 4 are in contact with the second surfaces 12 of the thermoelectric conversion modules 1 arranged on both sides of the heating heat exchanger 3 in the stacking direction and cool the second surfaces 12. The presser 5 is arranged on the opposite side of one of the two cooling heat exchangers 4 from the thermoelectric conversion module 1 in the stacking direction and elastically presses the cooling heat exchanger 4 toward the heating heat exchanger 3. The pair of bases 6 sandwich the heating heat exchanger 3, the thermoelectric conversion module 1, the two cooling heat exchangers 4, and the pressing device 5 in the stacking direction. The pair of bases 6 are integrally formed with each other and are disposed so as to be displaceable in the stacking direction.

[0121] With this configuration, the first surface 11 contacts the heating heat exchanger 3 and is heated by the heating heat exchanger 3, and the second surface 12 contacts the cooling heat exchanger 4 and is cooled by the cooling heat exchanger 4. This generates a temperature difference between the first surface 11 and the second surface 12, and the thermoelectric conversion module 1 generates electricity in response to the temperature difference. The pair of bases 6 are connected by the connector 7, so that the heating heat exchanger 3, the cooling heat exchanger 4, the presser 5, etc. are sandwiched between the pair of bases 6 in the stacking direction. This maintains contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4. For example, if the heating heat exchanger 3 expands and deforms, the cooling heat exchanger 4 is elastically pressed in the stacking direction by the presser 5, and therefore can be displaced in the stacking direction in response to the expansion and deformation. This ensures that contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4 is appropriately maintained. As a result, the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4 is improved, and the power generation efficiency is improved.

[0122] Here, the pair of bases 6 are arranged so as to be displaceable in the stacking direction. That is, the pair of bases 6 formed integrally by the connectors 7 are displaceable in the stacking direction relative to the fixed heating heat exchanger 3. Therefore, by simply providing a presser 5 on only one of the two cooling heat exchangers 4, in this example, only on the second cooling heat exchanger 4B side, both cooling heat exchangers 4 can be supported so as to be elastically displaceable in the stacking direction. That is, the second cooling heat exchanger 4B is elastically pressed in the stacking direction directly by the presser 5, and the first cooling heat exchanger 4A is elastically pressed in the stacking direction by the presser 5 via the pair of bases 6. This ensures appropriate contact not only between the second cooling heat exchanger 4B, the thermoelectric conversion module 1, and the heating heat exchanger 3, but also between the first cooling heat exchanger 4A, the thermoelectric conversion module 1, and the heating heat exchanger 3. As a result, the efficiency of heat exchange between the thermoelectric conversion module 1 and the heating heat exchanger 3, the first cooling heat exchanger 4A, and the second cooling heat exchanger 4B is improved. In this way, it is only necessary to provide the pressing device 5 on one side of the cooling heat exchanger 4, so that it is possible to improve the power generation efficiency and make the device more compact.

[0123] The power generation device 10 further includes a connector 7 that connects the pair of bases 6 to each other and thereby sandwiches the pair of bases 6. The connectors 7 are arranged on both sides of the heating heat exchanger 3 and the cooling heat exchanger 4 in the front-to-rear direction (i.e., a specific direction perpendicular to both the stacking direction and the up-and-down direction), and are in contact with both ends of the heating heat exchanger 3 in the front-to-rear direction.

[0124] According to this configuration, because the connectors 7 contact both ends of the heating heat exchanger 3 in the front-rear direction, the connectors 7 restrict the front-rear displacement of the pair of bases 6. In other words, by using the connectors 7, the front-rear displacement of the pair of bases 6 can be restricted. Therefore, deviation in the relative position of the pair of bases 6 with respect to the heating heat exchanger 3, the cooling heat exchanger 4, etc. in the front-rear direction is restricted. By restricting such deviation in the relative position, the heating heat exchanger 3, the cooling heat exchanger 4, etc. are properly sandwiched between the pair of bases 6. This makes it possible to more appropriately maintain contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4. As a result, power generation efficiency is further improved.

[0125] The connector 7 is formed in a rod shape extending in the stacking direction and has a shaft 71 connected to the pair of bases 6, and a cylindrical spacer 72 that is arranged between the pair of bases 6 with the shaft 71 inserted therethrough and maintains the spacing between the pair of bases 6, with the spacer 72 being arranged so as to contact both ends of the heating heat exchanger 3 in the front-to-rear direction.

[0126] According to this configuration, the sandwiching distance D between the pair of bases 6 is kept constant by the spacers 72, thereby appropriately maintaining contact between the thermoelectric conversion module 1 and the heating heat exchanger 3 and the cooling heat exchanger 4. The spacers 72 contact both ends of the heating heat exchanger 3 in the front-rear direction, thereby restricting the displacement of the pair of bases 6 in the front-rear direction. In this way, the use of the spacers 72 can restrict the displacement of the pair of bases 6 in the front-rear direction, so that a simple configuration can be used to suppress deviation in the relative position of the pair of bases 6 with respect to the heating heat exchanger 3, the cooling heat exchanger 4, etc. in the front-rear direction.

[0127] Other Embodiments As described above, the above-described embodiments have been described as examples of the technology disclosed in the present application. However, the technology of the present disclosure is not limited to these embodiments and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, the components described in the above-described embodiments can be combined to create new embodiments. Furthermore, the components described in the accompanying 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 exemplify the technology. Therefore, the fact that these non-essential components are described in the accompanying drawings or detailed description should not be interpreted as immediately determining that these non-essential components are essential.

[0128] For example, the connector 7 may be configured to contact both ends in the front-to-rear direction of the cooling heat exchanger 4 instead of the heating heat exchanger 3, or may be configured to contact both ends in the front-to-rear direction of both the heating heat exchanger 3 and the cooling heat exchanger 4.

[0129] Furthermore, the spacer 72 may have a tubular shape other than a cylindrical shape.

[0130] It is needless to say that the pressing device 5 may elastically press the first cooling heat exchanger 4A toward the heating heat exchanger 3 instead of the second cooling heat exchanger 4B.

[0131] Furthermore, the heating gas supplied to the main body 30 of the heating heat exchanger 3 is not limited to steam, but may be other condensable gases.

[0132] Furthermore, the cooling fluid supplied to the main body 40 of the cooling heat exchanger 4 is not limited to water, but may be other fluids.

[0133] Furthermore, the spring 51 of the pressing device 5 is not limited to a coil spring, but may be, for example, a leaf spring. In this case, too, the leaf spring is arranged so as to have elasticity in the stacking direction (i.e., the horizontal direction).

[0134] Furthermore, the power generation device 10 may be provided in a steam system other than the drain recovery system 100 .

[0135] As described above, the techniques of the present disclosure are useful for power generation devices and steam systems.

[0136] REFERENCE SIGNS LIST 10 Power generation device 1 Thermoelectric conversion module 11 First surface 12 Second surface 3 Heating heat exchanger 4 Cooling heat exchanger 4A First cooling heat exchanger 4B Second cooling heat exchanger 5 Pressurizer 6 Pair of bases 6A First base 6B Second base 7 Connector 71 Shaft 72 Spacer 100 Drain recovery system (steam system) 110 Gas-liquid separator 140 Heat recovery device 150 Liquid pressure transfer device (steam-using equipment, pump)

Claims

1. A thermoelectric conversion module having a first surface and a second surface facing opposite directions in a predetermined horizontal direction, which generates thermoelectric power according to the temperature difference between the first surface and the second surface, A fixed heating heat exchanger is provided, in which the thermoelectric conversion modules are arranged on both sides in the horizontal direction and are in contact with the first surface, heating the first surface. Two movable cooling heat exchangers are arranged on both sides of the heating heat exchanger, and are in contact horizontally with the second surface of each of the thermoelectric conversion modules, and cool the second surface. A presser is positioned in the horizontal direction opposite to the thermoelectric conversion module of one of the two cooling heat exchangers, and elastically presses the one cooling heat exchanger toward the heating heat exchanger. The heating heat exchanger, the thermoelectric conversion module, the two cooling heat exchangers, and the presser are each held horizontally by a pair of bases, The pair of bases are integrally formed with each other and are positioned to be displaceable in the horizontal direction relative to the heating heat exchanger. A power generation device characterized by the following features.

2. In the power generation apparatus according to claim 1, The pair of bases is connected to each other, and a connector is further provided that is clamped between the pair of bases. The connector is positioned on both sides of the heating heat exchanger and the cooling heat exchanger in a specific direction perpendicular to both the horizontal and vertical directions, and is in contact with at least one end of the heating heat exchanger and the cooling heat exchanger in the specific direction. A power generation device characterized by the following features.

3. In the power generation apparatus according to claim 2, The connector is formed in the shape of a rod extending horizontally and has a shaft connected to the pair of bases, and a cylindrical spacer positioned between the pair of bases with the shaft inserted through it, maintaining the distance between the pair of bases, wherein the spacer is positioned to be in contact with both ends of at least one of the heating heat exchanger and the cooling heat exchanger in the specific direction. 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, The heating heat exchanger is supplied with steam before it is supplied to the steam-using equipment, and the supplied steam heats the first surface. 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 pump is a steam-using device that uses supplied steam to pump out the drain. The cooling heat exchanger is supplied with cooling water before it is supplied to the heat recovery unit, and the supplied cooling water cools the second surface. A steam system characterized by the following features.