A waste heat recovery system for steam extraction condensate in a thermal power plant

Abstract

This invention discloses a waste heat recovery system for steam extraction condensate in a thermal power plant, comprising a gas return and discharge mechanism disposed above the inner cavity of a tank. The gas return and discharge mechanism includes a gas bladder telescopic assembly, a stroke amplification assembly, an electrical control assembly, and a steam return regulating assembly. A steam return port is located at the top of the tank and is connected to the heating steam pipe via a steam return pipe. An electric steam exhaust valve is installed on the exhaust port. The gas bladder telescopic assembly is sequentially connected to the steam return regulating assembly and the electrical control assembly via the stroke amplification assembly. The steam return regulating assembly and the electrical control assembly are electrically connected to the electric steam exhaust valve. The electrical control assembly switches the functions of the steam return regulating assembly and the electric steam exhaust valve. When the temperature at the exhaust port is high, it can perform reheating on the insufficiently heated steam. Simultaneously, by closing the steam return port, it prevents the discharge of insufficiently heated steam, thus avoiding energy waste.

Description

Technical Field

[0001] This invention relates to the technical field of waste heat recovery in thermal power plants, and in particular to a waste heat recovery system for steam extraction condensate from thermal power plants. Background Technology

[0002] Most power plants currently use extraction steam heating for centralized winter heating. The heating network heater is used to heat the heating water sent to the heating network. The heating steam comes from high-pressure steam extracted from the steam turbine or fresh steam drawn from the boiler and depressurized to serve as the heat source, heating the heating network water to the required delivery temperature.

[0003] According to the design of the existing waste heat recovery system, in order to maintain the pressure inside the heat exchange tank, the steam extracted after heat exchange will be directly discharged into the atmosphere. If the steam is discharged without complete heat exchange, it will result in energy waste.

[0004] In view of the above-mentioned related technologies, the present invention provides a waste heat recovery system for steam extraction condensate in thermal power plants. Summary of the Invention

[0005] This invention provides a waste heat recovery system for steam extraction condensate from a thermal power plant to solve the problems mentioned in the background art.

[0006] This invention provides a waste heat recovery system for steam extraction and condensate drainage in a thermal power plant, which adopts the following technical solution: it includes a tank and a heating steam pipe and a condensate drain installed in the tank. One end of the condensate drain is connected to a water tank. The top of the tank is provided with a steam vent. It also includes a gas return mechanism installed above the inner cavity of the tank.

[0007] The gas return and exhaust mechanism includes an airbag telescopic assembly, a stroke amplification assembly, an electrical control assembly, and a steam return regulating assembly. A steam return port is opened at the top of the tank. The steam return port is connected to the heating steam pipe through a steam return pipe. An electric steam exhaust valve is installed on the exhaust port. The airbag telescopic assembly is connected to the steam return regulating assembly and the electrical control assembly in sequence through the stroke amplification assembly. The steam return regulating assembly and the electrical control assembly are electrically connected to the electric steam exhaust valve.

[0008] Optionally, an umbrella-shaped baffle is installed above the inner cavity of the tank, and the baffle has multiple air holes evenly distributed on it.

[0009] By adopting the above technical solution, the condensed water droplets are guided to the inner wall of the tank, so that a large number of low-temperature water droplets can drip down along the inner wall of the tank.

[0010] Optionally, a drain pipe is connected to the bottom of the tank, and the drain pipe is connected to the water tank in sequence through a heating system and a water pump.

[0011] By adopting the above technical solution, the condensate drain pipe is used to discharge the condensate generated after the heating steam is extracted and used in the heating system for heating. Then, the water source after heating is reused in the water tank for heat exchange.

[0012] Optionally, the airbag telescopic assembly includes a mounting base fixed to the inner wall of the tank, on which an airbag is fixed, and the end of the airbag facing the stroke amplification assembly is a movable end.

[0013] By adopting the above technical solution, when the temperature of the steam above is high, the airbag expands, thereby driving the movable end to move a stroke.

[0014] Optionally, the stroke amplification assembly includes a hinge seat, a swing rod, a short hinge rod, a long hinge rod, a guide seat, and a transverse rod. The hinge seat is fixed to the inner wall of the tank. One end of the swing rod is hinged to the hinge seat. The other end of the swing rod is hinged to one end of the transverse rod through the long hinge rod. The other end of the transverse rod passes through the interior of the guide seat. One end of the short hinge rod is hinged to the outer wall of the swing rod away from the long hinge rod. The other end of the short hinge rod is connected to the movable end of the airbag telescopic assembly.

[0015] By adopting the above technical solution, when the movable end of the airbag telescopic assembly moves, the long articulated rod will drive the transverse rod to move laterally in the guide seat under the action of the swing rod.

[0016] Optionally, the steam return regulating assembly includes a regulating valve plate, the upper surface of which is fitted with the opening of the steam return port, one side wall of which is connected to the end of the transverse rod away from the guide seat, and a first electrical contact block is fixed to the other side wall of the regulating valve plate.

[0017] By adopting the above technical solution, the movement of the transverse rod will drive the regulating valve plate and the first electrical contact block to move. The movement of the regulating valve plate will open and close the return steam port, while the movement of the first electrical contact block will make contact with and disconnect from the second electrical contact block.

[0018] Optionally, the electronic control assembly includes a sliding seat fixed to the top of the inner cavity of the tank, a second electrical contact block movably connected to the sliding seat, one end of a spring connected to the side wall of the second electrical contact block away from the first electrical contact block, and the other end of the spring connected to the inner wall of the tank.

[0019] By adopting the above technical solution, during the contact process between the first electrical contact block and the second electrical contact block, the spring is compressed. When the first electrical contact block moves in the opposite direction under the action of the airbag telescopic component and the stroke amplification component, the spring will restore the second electrical contact block to its original position.

[0020] Optionally, the second electrical contact block and the first electrical contact block are electrically connected to the electric exhaust valve via a power supply line.

[0021] By adopting the above technical solution, when the second electric contact block is in contact with the first electric contact block, the electric exhaust valve is in the on state, thereby closing the exhaust port. Conversely, when the second electric contact block is not in contact with the first electric contact block, the electric exhaust valve is in the off state, thereby opening the exhaust port.

[0022] In summary, the present invention has at least one of the following beneficial effects:

[0023] This invention controls the operation of the return steam regulating component and the on / off power of the electrical control component through the airbag telescopic component and the stroke amplification component. The electrical control component will realize the function switching of the return steam regulating component and the electric exhaust valve. When the temperature at the exhaust port is high, it can reheat the steam that has not been sufficiently heated. At the same time, by closing the return steam port, it avoids the discharge of steam that has not been sufficiently heated, thus preventing energy waste. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the gas return mechanism of the present invention;

[0027] Figure 3 This is a schematic diagram of the specific components and structure of the gas return mechanism of the present invention.

[0028] Explanation of reference numerals in the attached drawings: 1. Tank body; 2. Heating steam pipe; 3. Condensate drain; 4. Water tank; 5. Steam vent; 6. Electric steam vent valve; 7. Airbag telescopic assembly; 701. Mounting base; 702. Airbag; 8. Stroke amplification assembly; 801. Hinge seat; 802. Swing rod; 803. Hinge short rod; 804. Hinge long rod; 805. Guide seat; 806. Lateral rod; 9. Electrical control assembly; 901. Sliding seat; 902. Second electrical contact block; 903. Spring; 10. Steam return regulating assembly; 1001. Regulating valve plate; 1002. First electrical contact block; 11. Steam return port; 12. Steam return pipe; 13. Baffle; 14. Drain pipe; 15. Heating system; 16. Water pump; Detailed Implementation

[0029] The following is in conjunction with the appendix Figure 1-3The present invention will be described in further detail below.

[0030] Reference Figures 1-2 This invention discloses a waste heat recovery system for steam extraction and condensate drainage in a thermal power plant, comprising a tank 1 and a steam pipe 2 and a condensate drain 3 disposed within the tank 1. One end of the condensate drain 3 is connected to a water tank 4. Steam extraction is introduced into the tank 1 through the steam pipe 2 to exchange heat with the condensate drain 3, thereby recovering and utilizing the heat energy of the steam extraction. After the steam extraction condenses, the condensate formed falls to the bottom of the tank 1. The top of the tank 1 is provided with a steam vent 5 to maintain the internal pressure and discharge the heat exchanged gas. The system also includes a gas return mechanism disposed above the inner cavity of the tank 1.

[0031] The gas return and exhaust mechanism includes an airbag telescopic assembly 7, a stroke amplification assembly 8, an electrical control assembly 9, and a steam return regulating assembly 10. A steam return port 11 is located at the top of the tank 1. The steam return port 11 is connected to the heating steam pipe 2 via a steam return pipe 12, used to recover and reheat steam that has not undergone sufficient heat exchange. An electric steam exhaust valve 6 is installed on the exhaust port 5. Controlling the electric steam exhaust valve 6 opens and closes the exhaust port 5, thus preventing the discharge of insufficiently heated steam and avoiding energy waste. The airbag telescopic assembly 7 is connected to the steam return regulating assembly 10 via the stroke amplification assembly 8. Component 10 is connected to the electrical control component 9. The airbag telescopic component 7 can automatically extend and retract according to the temperature of the steam above the tank 1. The stroke of the airbag telescopic component 7 is amplified by the stroke amplification component 8, which drives the return steam regulating component 10 to move. The return steam regulating component 10 regulates the opening and closing of the return steam port 11, thereby recovering the steam that has not been fully exchanged. The return steam regulating component 10 and the electrical control component 9 are electrically connected to the electric exhaust valve 6. The electrical control component 9 will realize the function switching between the return steam regulating component 10 and the electric exhaust valve 6.

[0032] Reference Figure 1 An umbrella-shaped baffle 13 is installed above the inner cavity of the tank body 1. Multiple air holes are evenly distributed on the baffle 13. The multiple baffles 13 cause the heating steam after passing through the condensate drain 3 to condense into water droplets again. The umbrella-shaped structure is conducive to guiding the condensed water droplets to the inner wall of the tank body 1, so that a large number of low-temperature water droplets can drip down along the inner wall of the tank body 1.

[0033] The bottom of the tank 1 is connected to a drain pipe 14. The drain pipe 14 is connected to the water tank 4 in sequence through the heating system 15 and the water pump 16. The drain pipe 14 is used to discharge the condensate generated after the heating steam is extracted and heat exchanged, and then use it in the heating system 15 for heating. The heated water is then reused in the water tank 4 for heat exchange.

[0034] Reference Figure 3The airbag telescopic assembly 7 includes a mounting base 701 fixed to the inner wall of the tank 1, and an airbag 702 fixed on the mounting base 701. The end of the airbag 702 facing the stroke amplification assembly 8 is the movable end. The airbag 702 is filled with gas. When the temperature of the steam above is high, the airbag 702 expands, thereby driving the movable end to move one stroke.

[0035] The stroke amplification assembly 8 includes a hinge seat 801, a swing rod 802, a short hinge rod 803, a long hinge rod 804, a guide seat 805, and a transverse rod 806. The hinge seat 801 is fixed to the inner wall of the tank body 1. One end of the swing rod 802 is hinged to the hinge seat 801, and the other end of the swing rod 802 is hinged to one end of the transverse rod 806 through the long hinge rod 804. The other end of the transverse rod 806 passes through the interior of the guide seat 805. One end of the short hinge rod 803 is hinged to the side of the outer wall of the swing rod 802 away from the long hinge rod 804. The other end of the short hinge rod 803 is connected to the movable end of the airbag telescopic assembly 7. When the short hinge rod 803 moves due to the movable end of the airbag telescopic assembly 7, the long hinge rod 804 will drive the transverse rod 806 to perform a limited transverse movement in the guide seat 805 under the action of the swing rod 802.

[0036] The steam return regulating assembly 10 includes a regulating valve plate 1001. The upper surface of the regulating valve plate 1001 is in contact with the opening of the steam return port 11. One side wall of the regulating valve plate 1001 is connected to the end of the transverse rod 806 away from the guide seat 805. A first electrical contact block 1002 is fixed to the other side wall of the regulating valve plate 1001. When the transverse rod 806 moves, it will drive the regulating valve plate 1001 and the first electrical contact block 1002 to move. The movement of the regulating valve plate 1001 will realize the opening and closing of the steam return port 11. The movement of the first electrical contact block 1002 will enable it to make contact with and disconnect from the second electrical contact block 902. The second electrical contact block 902 and the first electrical contact block 1002 are electrically connected to the electric exhaust valve 6 through a power line. When the second electrical contact block 902 is in contact with the first electrical contact block 1002, the electric exhaust valve 6 is in the on state, thereby closing the exhaust port 5. Conversely, when the second electrical contact block 902 is not in contact with the first electrical contact block 1002, the electric exhaust valve 6 is in the off state, thereby opening the exhaust port 5.

[0037] The electronic control assembly 9 includes a sliding seat 901 fixed to the top of the inner cavity of the tank 1. A second electrical contact block 902 is movably connected to the sliding seat 901. One end of a spring 903 is connected to the side wall of the second electrical contact block 902 away from the first electrical contact block 1002. The other end of the spring 903 is connected to the inner wall of the tank 1. During the contact between the first electrical contact block 1002 and the second electrical contact block 902, the spring 903 is compressed. When the first electrical contact block 1002 moves in the opposite direction under the action of the airbag telescopic assembly 7 and the stroke amplification assembly 8, the spring 903 will restore the second electrical contact block 902 to its original position.

[0038] The working principle of the waste heat recovery system for steam extraction condensate in a thermal power plant according to the present invention is as follows:

[0039] During operation, the extracted steam is introduced into the tank 1 through the steam pipe 2, where it exchanges heat with the condensate drain 3 to recover and utilize the heat energy of the extracted steam. The condensate from the extracted steam falls along the formed condensate to the bottom of the tank 1 for reuse. The extracted steam, after heat exchange, is discharged through the exhaust port 5. However, the heat exchange of the steam is insufficient, resulting in a high temperature at the exhaust port 5. To prevent energy waste due to high-temperature steam discharge, the airbag expansion component 7 expands due to heat. The stroke amplification component 8 amplifies the stroke of the airbag expansion component 7 and drives... The return steam regulating component 10 moves, thereby regulating the opening of the return steam port 11, allowing high-temperature steam to be introduced into the tank 1 along with the heating steam extraction for reheating. The movement of the return steam regulating component 10 energizes the electrical control component 9. After energization, the electric exhaust valve 6 closes the return steam port 11, preventing the high-temperature steam from being discharged. When the steam temperature above the tank 1 decreases, the return steam regulating component 10 closes the return steam port 11 to prevent low-temperature gas from entering the heating steam pipe 2. At the same time, after power is cut off, the electric exhaust valve 6 of the return steam port 11 opens.

[0040] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A waste heat recovery system for steam extraction condensate in a thermal power plant, comprising a tank (1) and a steam pipe (2) and a condensate drain (3) disposed within the tank (1), wherein one end of the condensate drain (3) is connected to a water tank (4), and a steam vent (5) is provided at the top of the tank (1), characterized in that: It also includes a gas return mechanism disposed above the inner cavity of the tank (1); The gas return mechanism includes an airbag telescopic assembly (7), a stroke amplification assembly (8), an electrical control assembly (9), and a steam return regulating assembly (10). The top of the tank (1) has a steam return port (11), which is connected to the heating steam pipe (2) through a steam return pipe (12). An electric steam exhaust valve (6) is installed on the exhaust port (5). The airbag telescopic assembly (7) is connected to the steam return regulating assembly (10) and the electrical control assembly (9) in sequence through the stroke amplification assembly (8). The steam return regulating assembly (10) and the electrical control assembly (9) are electrically connected to the electric steam exhaust valve (6). The airbag telescopic assembly (7) includes a mounting base (701) fixed on the inner wall of the tank (1), an airbag (702) fixed on the mounting base (701), and the end of the airbag (702) facing the stroke amplification assembly (8) is the movable end; The stroke amplification assembly (8) includes a hinge seat (801), a swing rod (802), a short hinge rod (803), a long hinge rod (804), a guide seat (805), and a transverse rod (806). The hinge seat (801) is fixed to the inner wall of the tank (1). One end of the swing rod (802) is hinged to the hinge seat (801). The other end of the swing rod (802) is hinged to one end of the transverse rod (806) through the long hinge rod (804). The other end of the transverse rod (806) passes through the interior of the guide seat (805). The side of the outer wall of the swing rod (802) away from the long hinge rod (804) is hinged to one end of the short hinge rod (803). The other end of the short hinge rod (803) is connected to the movable end of the airbag telescopic assembly (7). By controlling the electric exhaust valve (6), the exhaust port (5) is opened and closed, thereby avoiding the discharge of steam that has not been fully heat-exchanged, which would cause energy waste. The airbag telescopic assembly (7) is connected to the return steam regulating assembly (10) and the electrical control assembly (9) in sequence through the stroke amplification assembly (8). The airbag telescopic assembly (7) can automatically extend and retract according to the temperature of the steam above the tank (1). The stroke of the airbag telescopic assembly (7) is amplified by the stroke amplification assembly (8), and the return steam regulating assembly (10) is driven to move. Thus, the return steam regulating assembly (10) regulates the opening and closing of the return steam port (11), thereby recovering the steam that has not been fully exchanged. The return steam regulating assembly (10) and the electrical control assembly (9) are electrically connected to the electric exhaust valve (6). The electrical control assembly (9) will realize the function switching of the return steam regulating assembly (10) and the electric exhaust valve (6).

2. The waste heat recovery system for steam extraction condensate in a thermal power plant according to claim 1, characterized in that: An umbrella-shaped baffle (13) is installed above the inner cavity of the tank (1), and multiple air holes are evenly distributed on the baffle (13).

3. The waste heat recovery system for steam extraction condensate in a thermal power plant according to claim 1, characterized in that: The bottom of the tank (1) is connected to a drain pipe (14), which is connected to the water tank (4) in sequence through a heating system (15) and a water pump (16).

4. The waste heat recovery system for steam extraction condensate in a thermal power plant according to claim 1, characterized in that: The steam return regulating assembly (10) includes a regulating valve plate (1001), the upper surface of which is in contact with the opening of the steam return port (11), one side wall of which is connected to the end of the transverse rod (806) away from the guide seat (805), and the other side wall of which is fixed with a first electrical contact block (1002).

5. A waste heat recovery system for steam extraction condensate in a thermal power plant according to claim 1, characterized in that: The electronic control assembly (9) includes a sliding seat (901) fixed to the top of the inner cavity of the tank (1). A second electrical contact block (902) is movably connected to the sliding seat (901). One end of a spring (903) is connected to the side wall of the second electrical contact block (902) away from the first electrical contact block (1002). The other end of the spring (903) is connected to the inner wall of the tank (1).

6. A waste heat recovery system for steam extraction condensate in a thermal power plant according to claim 5, characterized in that: The second electrical contact block (902) and the first electrical contact block (1002) are electrically connected to the electric exhaust valve (6) via a power line.

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