Waste heat recovery device

Abstract

The present application discloses a waste heat recovery device, which relates to the field of boiler steam power generation, and includes: a condenser, which has a steam inlet and a condensate discharge pipe; a steam pipe, whose first end is connected to the steam inlet and whose second end is used to connect to the steam turbine; a return pipe, whose first end is connected to the condensate discharge pipe and whose second end is used to connect to the water inlet pipe of the boiler; a heat exchange pipe, whose first end is connected to the condensate discharge pipe and whose second end is connected to the return pipe after passing through the steam pipe, and the heat exchange pipe has a heat exchange section located inside the steam pipe; a flow control structure is provided at the joint between the heat exchange pipe and the condensate discharge pipe, and the flow control structure includes: a stopper, which is fixed on the side wall of the heat exchange pipe; a rotating baffle, whose one end is rotatably arranged on the stopper or the side wall of the heat exchange pipe, and the rotating baffle has an initial state and a top open state. The present application can effectively utilize the steam tail gas of the steam turbine and reasonably heat the condensate.

Description

Technical Field

[0001] The invention relates to the field of boiler steam power generation, and in particular to a waste heat recovery device. Background Art

[0002] The principle of boiler power generation is to convert water into steam through the heat energy released by fuel combustion, and then use the steam to drive the blades of the steam turbine to rotate, thereby driving the generator to generate electricity. The steam exhaust gas after work will enter the condenser to cool into water and then be recycled to the boiler. The steam exhaust gas also carries a lot of heat, which cannot be well utilized by existing technology. Summary of the invention

[0003] In view of the above problems, the present invention proposes a waste heat recovery device.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A waste heat recovery device, comprising:

[0006] a condenser having a steam inlet and a condensate discharge pipe;

[0007] a steam pipe, wherein a first end of the steam pipe is connected to the steam inlet, and a second end of the steam pipe is used to be connected to the steam turbine to receive steam tail gas from the steam turbine;

[0008] a water return pipe, wherein a first end of the water return pipe is connected to the condensed water discharge pipe, and a second end of the water return pipe is used to be connected to a water inlet pipe of the boiler; and

[0009] A heat exchange tube, wherein a first end of the heat exchange tube is connected to the condensed water discharge pipe, a second end of the heat exchange tube passes through the steam pipe and is connected to the return water pipe, and the heat exchange tube has a heat exchange section located inside the steam pipe;

[0010] The joint between the heat exchange tube and the condensed water discharge pipe has a flow control structure, and the flow control structure includes:

[0011] A stopper, fixed on the side wall of the heat exchange tube;

[0012] A rotating baffle has one end rotatably arranged on a baffle or a side wall of a heat exchange tube. The rotating baffle has an initial state and a top-open state. When the rotating baffle is in the initial state, the rotating baffle and the baffle are abutted against each other. A flow channel for condensed water to pass through is provided between the rotating baffle and the heat exchange tube. When the rotating baffle is in the top-open state, the rotating baffle is rotated toward a side away from the baffle by the action of steam from the heat exchange section, thereby enlarging the flow channel.

[0013] The present application divides the water condensed by the condenser into two parts. The first part is discharged through the return pipe, and the second part enters the steam pipe through the heat exchange pipe for heating. After heating, it merges with the condensed water in the return pipe. After merging, the overall temperature of the condensed water will be higher than the temperature when it is discharged from the condenser. The present application can effectively utilize the steam exhaust gas of the steam turbine. When the condensed water in the heat exchange section is overheated to generate steam, the steam will move to the rotating baffle, which can exert a force on the rotating baffle to make the rotating baffle in the top open state. At this time, the flow channel becomes larger, and more condensed water will flow into the heat exchange pipe, which can effectively prevent the condensed water from being overheated.

[0014] In the present application, the flow channel becomes larger, which means that the opening becomes larger, and the water flow rate can be increased under the same conditions.

[0015] In actual use, the portion of the heat exchange tube passing through the steam pipe is provided with a sealing structure, and the sealing structure is preferably formed by welding.

[0016] In one embodiment of the present invention, the rotating baffle has a notch.

[0017] The notch is used to form the flow channel.

[0018] In one embodiment of the present invention, the notch is formed at one end of the rotation baffle away from the rotation end of the rotation baffle.

[0019] In one embodiment of the present invention, the rotating end of the rotating baffle is the front end, the end away from the rotating end of the rotating baffle is the rear end, and the left end and / or the right end of the rotating baffle has the notch.

[0020] The left end and / or the right end of the rotating baffle has the notch, and such an arrangement can increase the force arm, making it easier to push the rotating baffle open compared to an arrangement at the rear end.

[0021] In one embodiment of the present invention, the first end of the heat exchange tube is connected to the lower end surface of the condensate discharge pipe, and the first end of the return pipe is connected to the side wall of the lower end of the condensate discharge pipe.

[0022] In one embodiment of the present invention, a control valve is installed at the first end of the return pipe, and the control valve is used to control the water inlet opening area of ​​the first end of the return pipe; the part of the return pipe between the second end of the return pipe and the second end of the heat exchange tube is a mixing section, and a temperature sensor is installed in the mixing section.

[0023] The control valve can be controlled according to the temperature data obtained by the temperature sensor. For example, when the measured temperature is low, the control valve can be controlled to reduce the area of ​​the water inlet opening of the return pipe so that more condensed water can enter the heat exchange tube. For example, when the measured temperature is high, the control valve can be controlled to increase the area of ​​the water inlet opening of the return pipe so that more condensed water can enter the return pipe.

[0024] In one embodiment of the present invention, the control valve is an electric control valve.

[0025] The electric control valve can cooperate with the temperature sensor to achieve automatic control by setting the threshold.

[0026] In one embodiment of the present invention, a mixing blade is installed in the mixing section, and the temperature sensor is arranged between the second end of the return pipe and the mixing blade.

[0027] The condensed water from the heat exchange tube and the return water pipe merge to drive the mixing blades to rotate. The rotation of the mixing blades can quickly mix the two evenly, making the temperature measured by the temperature sensor more accurate.

[0028] In one embodiment of the present invention, the mixing blade is adjacent to the second end of the heat exchange tube.

[0029] In one embodiment of the present invention, the condenser includes a shell, and a condenser tube is provided in the shell and is bent or spirally arranged. The upper end of the condenser tube is the steam inlet, and the lower end of the condenser tube is connected to the condensate discharge pipe.

[0030] The shell is also provided with a condensing medium inlet and a condensing medium outlet.

[0031] In actual use, a sealed space is formed in the shell, with the condensing medium inlet at the bottom and the condensing medium outlet at the top. The condenser exchanges heat through direct contact between the condensing medium in the sealed space in the shell and the outer wall of the condenser tube, turning the steam in the condenser tube into condensed water.

[0032] In actual use, a medium pipeline wrapped around the outside of the condensation tube may be provided in the shell, one end of the medium pipeline being the condensation medium inlet and the other end being the condensation medium outlet.

[0033] The beneficial effects of the present invention are as follows: the present application divides the water condensed by the condenser into two parts, the first part is discharged through the return pipe, and the second part enters the steam pipe through the heat exchange pipe for heating, and then merges with the condensed water in the return pipe after heating. After merging, the overall temperature of the condensed water will be higher than the temperature when it is discharged from the condenser. The present application can effectively utilize the steam exhaust gas of the steam turbine. When the condensed water in the heat exchange section is overheated to generate steam, the steam will move to the rotating baffle, and can exert a force on the rotating baffle to make the rotating baffle in the top open state. At this time, the flow channel becomes larger, and more condensed water will flow into the heat exchange pipe, which can effectively prevent the condensed water from being overheated. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic diagram of a waste heat recovery device;

[0035] Figure 2 is a partial cross-sectional view of the waste heat recovery device when the rotating baffle is in an initial state;

[0036] Figure 3 yes Figure 2 The enlarged view of point A in the middle;

[0037] Figure 4 yes Figure 3 Schematic diagram of the rotating baffle being switched to the top-open state;

[0038] Figure 5 This is a schematic diagram of a condenser.

[0039] The reference numerals in the figures are:

[0040] 1. Condenser; 11. Shell; 12. Condenser pipe; 13. Steam inlet; 14. Condensate discharge pipe; 15. Condensate medium inlet; 16. Condensate medium outlet; 2. Steam pipe; 21. First end of the steam pipe; 22. Second end of the steam pipe; 3. Return pipe; 31. First end of the return pipe; 32. Second end of the return pipe; 33. Mixing section; 4. Heat exchange pipe; 41. First end of the heat exchange pipe; 42. Second end of the heat exchange pipe; 43. Heat exchange section; 5. Flow control structure; 51. Block; 52. Rotating baffle; 521. Front end; 522. Rear end; 523. Notch; 53. Flow channel; 6. Control valve; 7. Temperature sensor; 8. Mixing blade. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0042] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0043] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] The present invention is described in detail below in conjunction with the accompanying drawings.

[0045] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a waste heat recovery device comprises:

[0046] Condenser 1, having a steam inlet 13 and a condensed water discharge pipe 14;

[0047] A steam pipe 2, wherein a first end 21 of the steam pipe is connected to the steam inlet 13, and a second end 22 of the steam pipe is used to be connected to the steam turbine to receive steam exhaust gas from the steam turbine;

[0048] A water return pipe 3, wherein a first end 31 of the water return pipe is connected to the condensate discharge pipe 14, and a second end 32 of the water return pipe is used to be connected to the water inlet pipe of the boiler; and

[0049] The heat exchange tube 4 has a first end 41 connected to the condensate discharge pipe 14, and a second end 42 of the heat exchange tube passes through the steam pipe 2 and is connected to the return water pipe 3. The heat exchange tube 4 has a heat exchange section 43 located inside the steam pipe 2. Figure 2 ;

[0050] The joint between the heat exchange tube 4 and the condensed water discharge pipe 14 has a flow control structure 5, and the flow control structure 5 includes:

[0051] The stopper 51 is fixed on the side wall of the heat exchange tube 4;

[0052] The rotating baffle 52 has one end that is rotatably disposed on the baffle 51 or the side wall of the heat exchange tube 4. The rotating baffle 52 has an initial state and an open state. When the rotating baffle 52 is in the initial state, Figure 3 The rotating baffle 52 and the stopper 51 are in contact with each other, and a flow channel 53 for condensed water to pass through is provided between the rotating baffle 52 and the heat exchange tube 4. When the rotating baffle 52 is in the top open state, Figure 4 The rotating baffle 52 is acted upon by the steam from the heat exchange section 43 to rotate toward the side away from the baffle 51, thereby enlarging the flow channel 53.

[0053] The present application divides the water condensed by the condenser 1 into two parts. The first part is discharged through the return pipe 3, and the second part enters the steam pipe 2 through the heat exchange pipe 4 for heating. After heating, it merges with the condensed water in the return pipe 3. After merging, the overall temperature of the condensed water will be higher than the temperature when it is discharged from the condenser 1. The present application can effectively utilize the steam exhaust gas of the steam turbine. When the condensed water in the heat exchange section 43 is overheated to generate steam, the steam will move to the rotating baffle 52, and a force can be applied to the rotating baffle 52 to make the rotating baffle 52 in an open state. At this time, the flow channel 53 becomes larger, and more condensed water will flow into the heat exchange pipe 4, which can effectively prevent the condensed water from being overheated.

[0054] In the present application, the flow channel 53 becomes larger, which means that the opening becomes larger, and the water flow can be increased under the same conditions.

[0055] In actual use, the portion of the heat exchange tube 4 passing through the steam tube 2 is provided with a sealing structure, and the sealing structure is preferably formed by welding.

[0056] In this embodiment, the rotating baffle 52 has a notch 523 at one end away from the rotating end of the rotating baffle 52. The notch 523 is used to form the flow channel 53.

[0057] In this embodiment, the rotating end of the rotating baffle 52 is the front end 521, and the end away from the rotating end of the rotating baffle 52 is the rear end 522. In actual use, a notch 523 can be provided at the left end or / and the right end of the rotating baffle 52. The notch 523 at the left end or / and the right end of the rotating baffle 52 can increase the force arm, and it is easier to push the rotating baffle 52 open than when the notch is provided at the rear end 522.

[0058] like Figure 3 and Figure 4 As shown, in this embodiment, the first end 41 of the heat exchange tube is connected to the lower end surface of the condensate discharge pipe 14 , and the first end 31 of the return pipe is connected to the side wall of the lower end of the condensate discharge pipe 14 .

[0059] like Figure 2As shown, in this embodiment, a control valve 6 is installed at the first end 31 of the return pipe, and the control valve 6 is used to control the water inlet opening area of ​​the first end 31 of the return pipe; the part of the return pipe 3 between the second end 32 of the return pipe and the second end 42 of the heat exchange tube is a mixing section 33, and a temperature sensor 7 is installed in the mixing section 33.

[0060] The control valve 6 can be controlled according to the temperature data obtained by the temperature sensor 7. For example, when the measured temperature is low, the control valve 6 can be controlled to reduce the area of ​​the water inlet opening of the return pipe 3 so that more condensed water can enter the heat exchange tube 4. For example, when the measured temperature is high, the control valve 6 can be controlled to increase the area of ​​the water inlet opening of the return pipe 3 so that more condensed water can enter the return pipe 3.

[0061] In this embodiment, the control valve 6 is an electric control valve, which can cooperate with the temperature sensor 7 to achieve automatic control by setting a threshold.

[0062] like Figure 2 As shown, in this embodiment, a mixing blade 8 is installed in the mixing section 33, and the temperature sensor 7 is arranged between the second end 32 of the return pipe and the mixing blade 8. After the condensed water of the heat exchange tube 4 and the return pipe 3 merge, the mixing blade 8 is driven to rotate, and the rotation of the mixing blade 8 can quickly mix the two and make the temperature measured by the temperature sensor 7 more accurate.

[0063] In this embodiment, the mixing blade 8 is adjacent to the second end 42 of the heat exchange tube.

[0064] like Figure 1 and Figure 5 As shown, in this embodiment, the condenser 1 includes a shell 11, and a condenser tube 12 is provided in the shell 11 and is arranged to be reciprocated or spirally arranged. The upper end of the condenser tube 12 is a steam inlet 13, and the lower end of the condenser tube 12 is connected to a condensed water discharge pipe 14;

[0065] The housing 11 also has a condensing medium inlet 15 and a condensing medium outlet 16 .

[0066] In actual use, a sealed space is formed in the shell 11, with the condensing medium inlet 15 at the bottom and the condensing medium outlet 16 at the top. The condenser 1 exchanges heat through the condensing medium in the sealed space in the shell 11 directly contacting the outer wall of the condensing tube 12, so that the steam in the condensing tube 12 is converted into condensed water.

[0067] In actual use, a medium pipeline may be arranged in the shell 11 and wound around the outside of the condensation tube 12 , with one end of the medium pipeline being a condensation medium inlet 15 and the other end being a condensation medium outlet 16 .

[0068] The above description is only a preferred embodiment of the present invention, and does not limit the patent protection scope of the present invention. Any equivalent structural transformation made by using the contents of the present invention and the drawings, directly or indirectly used in other related technical fields, is also included in the protection scope of the present invention.

Claims

1. A waste heat recovery device, characterized in that: include: a condenser having a steam inlet and a condensate discharge pipe; a steam pipe, wherein a first end of the steam pipe is connected to the steam inlet, and a second end of the steam pipe is used to be connected to the steam turbine to receive steam tail gas from the steam turbine; A water return pipe, wherein a first end of the water return pipe is connected to the condensate discharge pipe, and a second end of the water return pipe is used to be connected to the water inlet pipe of the boiler; as well as A heat exchange tube, wherein a first end of the heat exchange tube is connected to the condensed water discharge pipe, a second end of the heat exchange tube passes through the steam pipe and is connected to the return water pipe, and the heat exchange tube has a heat exchange section located inside the steam pipe; The joint between the heat exchange tube and the condensed water discharge pipe has a flow control structure, and the flow control structure includes: A stopper, fixed on the side wall of the heat exchange tube; A rotating baffle has one end rotatably arranged on a baffle or a side wall of a heat exchange tube. The rotating baffle has an initial state and a top-open state. When the rotating baffle is in the initial state, the rotating baffle and the baffle are abutted against each other. A flow channel for condensed water to pass through is provided between the rotating baffle and the heat exchange tube. When the rotating baffle is in the top-open state, the rotating baffle is rotated toward a side away from the baffle by the action of steam from the heat exchange section, thereby enlarging the flow channel.

2. The waste heat recovery device according to claim 1, characterized in that: The rotating baffle has a notch.

3. The waste heat recovery device according to claim 2, characterized in that: The notch is provided at one end of the rotating baffle away from the rotating end of the rotating baffle.

4. The waste heat recovery device according to claim 2, characterized in that: The rotating end of the rotating baffle is the front end, the end away from the rotating end of the rotating baffle is the rear end, and the left end and / or the right end of the rotating baffle has the notch.

5. The waste heat recovery device according to claim 1, characterized in that: The first end of the heat exchange tube is connected to the lower end surface of the condensed water discharge pipe, and the first end of the return pipe is connected to the side wall of the lower end of the condensed water discharge pipe.

6. The waste heat recovery device according to claim 5, characterized in that: A control valve is installed at the first end of the return pipe, and the control valve is used to control the water inlet opening area of ​​the first end of the return pipe; the part of the return pipe between the second end of the return pipe and the second end of the heat exchange tube is a mixing section, and a temperature sensor is installed in the mixing section.

7. The waste heat recovery device according to claim 6, characterized in that: The control valve is an electrically controlled valve.

8. The waste heat recovery device according to claim 6, characterized in that: A mixing blade is installed in the mixing section, and the temperature sensor is arranged between the second end of the return water pipe and the mixing blade.

9. The waste heat recovery device according to claim 8, characterized in that: The mixing blade is adjacent to the second end of the heat exchange tube.

10. The waste heat recovery device according to claim 1, characterized in that: The condenser comprises a shell, wherein a condenser tube is disposed in a reciprocating or spiral manner, wherein the upper end of the condenser tube is the steam inlet, and the lower end of the condenser tube is connected to the condensate discharge pipe; The shell is also provided with a condensing medium inlet and a condensing medium outlet.

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