Thermal power plant heat energy recovery device

Abstract

The invention relates to the technical field of heat energy recovery, in particular to a thermal power plant heat energy recovery device which comprises an air inlet device, an air outlet pipe, a heat exchanger, a water inlet device and a water outlet pipe. The left end of the water inlet device is fixedly connected with the heat exchanger, and the right end of the water outlet pipe is fixedly connected with the heat exchanger. The flow speed of hot air is reduced through the diffuser, meanwhile, the hot air is diffused, and the hot air uniformly enters the shell through the flow equalizing plate, so that airflow distribution is uniform, the heat exchange efficiency is improved, meanwhile, material aging is reduced, the flue gas inlet temperature, the flue gas outlet temperature and the circulating water outlet temperature are monitored in real time through the temperature sensors, and the heat exchange efficiency is improved. And the electric valve is controlled by the PLC in real time to adjust the water flow speed, so that the heat energy recovery effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of heat recovery, and in particular to a heat recovery device for a thermal power plant. Background Art

[0002] Flue gas waste heat recovery technology in thermal power plants is an important means to improve energy utilization efficiency. Currently, common solutions include heat pipe heat exchangers, economizers, air preheaters, etc. Among them, heat pipe heat exchangers are widely used due to their high heat transfer efficiency and compact structure. In addition, some systems use spray heat exchange or phase change heat storage technology to further recover low-temperature waste heat. Existing technologies usually use circulating water or air at a fixed flow rate to exchange heat with flue gas, and rely on basic control systems to adjust operating parameters.

[0003] Existing waste heat recovery devices can achieve certain energy-saving effects, but there are still problems. First, the airflow distribution is uneven. When the flue gas enters the heat exchanger, it is easy to form a biased flow, resulting in a decrease in heat exchange efficiency in local areas. On the other side, the concentration of high-temperature flue gas may accelerate material aging; second, energy efficiency monitoring is insufficient. Most existing systems only display basic temperature and pressure data and cannot change the water flow rate in real time. When the flow rate is too fast, it may lead to poor heat recovery effect.

[0004] Therefore, in order to solve the above problems, the present invention proposes a heat energy recovery device for a thermal power plant. Summary of the Invention

[0005] In order to overcome the problem of uneven airflow distribution, which easily forms biased flow when flue gas enters the heat exchanger, resulting in a decrease in heat exchange efficiency in local areas, and the concentration of high-temperature flue gas on the other side may accelerate material aging, the present invention proposes a heat energy recovery device for a thermal power plant.

[0006] The technical solution of the present invention is: a heat energy recovery device for a thermal power plant, including an air intake device, an air outlet pipe, a heat exchanger, a water inlet device and a water outlet pipe, the rear end of the air intake device is fixedly connected to the heat exchanger, the front end of the air outlet pipe is fixedly connected to the heat exchanger, the left end of the water inlet device is fixedly connected to the heat exchanger, and the right end of the water outlet pipe is fixedly connected to the heat exchanger.

[0007] Preferably, the air intake device includes an air intake pipe 1, a connecting frame 1 is fixedly connected to the surface of the air intake pipe 1, an air intake pipe 2 is provided at the rear end of the air intake pipe 1, a connecting frame 2 is fixedly connected to the surface of the air intake pipe 2, and the connecting frame 1 and the connecting frame 2 are fixedly connected by multiple sets of bolts.

[0008] Preferably, a connection frame three is fixedly connected to the surface of the intake pipe two, a diffuser is provided at the rear end of the intake pipe two, a connection frame four is fixedly connected to the surface of the diffuser, and the connection frame three and the connection frame four are fixedly connected by multiple sets of bolts.

[0009] Preferably, the interior of the air intake pipe 2 is fixedly connected with filter 1, filter 2 and filter 3. Filter 1 is made of metal fiber, filter 2 is made of P high-temperature resistant fiber, filter 3 is made of activated carbon, and the interior of the diffuser is fixedly connected with a flow equalizing plate.

[0010] Preferably, the heat exchanger includes a shell, a rectangular groove 1 is opened on the left side of the front end of the shell, the rear end of the diffuser is fixedly connected to the rectangular groove 1 of the shell, a rectangular groove 2 is opened on the right side of the rear end of the shell, and the rear end of the rectangular groove 2 of the shell is fixedly connected to the outlet pipe.

[0011] Preferably, heating tube one, heating tube two and heating tube three are evenly arranged inside the shell, and heating tube one, heating tube two and heating tube three are all arranged in a multiple bending structure.

[0012] Preferably, two blocking plates are fixedly connected to the interior of the shell, the rear end of the blocking plate at the left end is not connected to the rear end of the interior of the shell, and the front end of the blocking plate at the right end is not connected to the front end of the interior of the shell, and the surfaces of heating tube one, heating tube two and heating tube three are fixedly connected with multiple fixing rings, and the surface of each fixing ring is fixedly connected with a connecting plate, and the connecting plates are fixedly connected to the shell and the blocking plate.

[0013] Preferably, the water inlet device includes a water inlet pipe, and the end of the water inlet pipe close to the shell is fixedly connected to a connecting pipe, and the end of the connecting pipe close to the shell is set as three outlets, and the three outlets are fixedly connected to heating tube one, heating tube two and heating tube three respectively.

[0014] Preferably, a water outlet pipe is fixedly connected to the left end of the shell, and three outlets are set at one end of the water outlet pipe close to the shell. The three outlets are fixedly connected to heating tube one, heating tube two and heating tube three respectively. The lower end of the shell is symmetrically fixedly connected to two horizontal plates one, and the lower end of each horizontal plate one is symmetrically fixedly connected to two support plates, and the lower ends of the two support plates located on the same horizontal plate one are commonly fixedly connected to horizontal plate two.

[0015] Preferably, the device also includes a PLC control system, an electric valve is provided on the surface of the water inlet pipe, temperature sensors are provided inside the air inlet pipe 1, the air outlet pipe and the water outlet pipe, and flow meters are provided inside the heating pipe 1, the heating pipe 2 and the heating pipe 3.

[0016] Beneficial effects of the present invention:

[0017] 1. The hot air enters the intake pipe 2 through the intake pipe 1, and is filtered by the filter 1, filter 2 and filter 3 inside the intake pipe 2. The filtered gas passes through the diffuser to reduce the hot air flow rate and diffuse the hot air at the same time. The hot air passes through the equalizer plate and enters the interior of the shell evenly, thereby making the airflow evenly distributed, improving the efficiency of heat exchange, and reducing material aging.

[0018] 2. Hot air enters the shell through the air inlet pipe 1, and cold water enters the heating pipe 1, heating pipe 2 and heating pipe 3 through the water inlet pipe. The flue gas inlet temperature, flue gas outlet temperature and circulating water outlet temperature are monitored in real time by temperature sensors. If the outlet water temperature is low, the electric valve is controlled by the PLC to reduce the water flow rate, thereby improving the heat recovery effect.

[0019] 3. Due to the obstruction of the two blocking plates 28, the hot air can only flow through the specified route to the rectangular groove 2 14, so that the hot air can stay in the heat exchanger longer. Since the heating tube 1 18, the heating tube 2 19 and the heating tube 3 20 have a multiple-bend structure, the water can stay in the heat exchanger longer, thereby improving the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The overall three-dimensional structure of the present invention is shown Figure 1 ;

[0021] Figure 2 The overall three-dimensional structure of the present invention is shown Figure 2 ;

[0022] Figure 3 Shown is a schematic diagram of the structure of the air intake device of the present invention;

[0023] Figure 4 Shown is a schematic diagram of the cross-sectional structure of the air intake device of the present invention;

[0024] Figure 5 Shown is a schematic diagram of the internal structure of the housing of the present invention;

[0025] Figure 6 Shown is a schematic diagram of the structure of a heating tube of the present invention;

[0026] Figure 7 Shown is a schematic diagram of the structure of the horizontal plate of the present invention.

[0027] Explanation of the accompanying drawings: 1. Shell; 2. Air inlet pipe 1; 3. Connecting frame 1; 4. Connecting frame 2; 5. Air inlet pipe 2; 6. Connecting frame 3; 7. Connecting frame 4; 8. Diffuser; 9. Filter screen 1; 10. Filter screen 2; 11. Filter screen 3; 12. Flow equalizing plate; 13. Rectangular groove 1; 14. Rectangular groove 2; 15. Air outlet pipe; 16. Water inlet pipe; 17. Connecting pipe; 18. Heating pipe 1; 19. Heating pipe 2; 20. Heating pipe 3; 21. Water outlet pipe; 22. Fixing ring; 23. Connecting plate; 24. Electric valve; 25. Horizontal plate 1; 26. Support plate; 27. Horizontal plate 2; 28. Blocking plate. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0029] See also Figure 1-Figure 7 The present invention provides an embodiment: a heat energy recovery device for a thermal power plant, comprising an air intake device, an air outlet pipe 15, a heat exchanger, a water inlet device and a water outlet pipe 21, wherein the rear end of the air intake device is fixedly connected to the heat exchanger, the front end of the air outlet pipe 15 is fixedly connected to the heat exchanger, the left end of the water inlet device is fixedly connected to the heat exchanger, and the right end of the water outlet pipe 21 is fixedly connected to the heat exchanger.

[0030] Furthermore, hot air enters the heat exchanger through the air inlet device, and cold water enters the heat exchanger through the water inlet device. After the hot air and cold water exchange heat in the heat exchanger, the gas is discharged through the air outlet pipe 15, and the heated hot water flows out through the water outlet pipe 21.

[0031] See also Figure 3 and Figure 4 The air intake device includes an air intake pipe 2, a connection frame 3 is fixedly connected to the surface of the air intake pipe 2, an air intake pipe 2 5 is provided at the rear end of the air intake pipe 2, a connection frame 2 4 is fixedly connected to the surface of the air intake pipe 2 5, and the connection frame 3 and the connection frame 2 4 are fixedly connected by multiple sets of bolts.

[0032] The surface of the air intake pipe 2 5 is fixedly connected to a connection frame 3 6 , the rear end of the air intake pipe 2 5 is provided with a diffuser 8 , the surface of the diffuser 8 is fixedly connected to a connection frame 4 7 , and the connection frame 3 6 and the connection frame 4 7 are fixedly connected by multiple sets of bolts.

[0033] The interior of the air intake pipe 2 5 is fixedly connected with filter 1 9 , filter 2 10 and filter 3 11 . Filter 1 9 is made of metal fiber, filter 2 10 is made of P84 high-temperature resistant fiber, and filter 3 11 is made of activated carbon. The interior of the diffuser 8 is fixedly connected with a flow equalizing plate 12 .

[0034] Furthermore, the hot air enters the intake pipe 2 5 through the intake pipe 1 2, and is filtered by the filter 1 9, filter 2 10 and filter 3 11 inside the intake pipe 2 5. The filtered gas passes through the diffuser 8 to reduce the hot air flow rate and diffuse the hot air at the same time. The hot air passes through the equalizing plate 12 to evenly enter the interior of the shell 1, thereby making the air flow evenly distributed, improving the heat exchange efficiency, and reducing the aging of the material. At the same time, when the filter 1 9, filter 2 10 and filter 3 11 need to be replaced, the intake pipe 2 5 is disassembled by removing the bolts on the connecting frame 1 3 and the connecting frame 2 4 and the connecting frame 3 6 and the connecting frame 4 7, and then the filter inside it is replaced. The replacement efficiency is high, the downtime is short, and the efficiency of heat energy recovery is improved.

[0035] See also Figure 5 The heat exchanger includes a shell 1, a rectangular groove 13 is opened on the left side of the front end of the shell 1, the rear end of the diffuser 8 is fixedly connected to the rectangular groove 13 of the shell 1, and a rectangular groove 2 is opened on the right side of the rear end of the shell 1. The rear end of the rectangular groove 2 14 of the shell 1 is fixedly connected to the outlet pipe 15.

[0036] The interior of the shell 1 is evenly provided with heating tube 1 18 , heating tube 2 19 and heating tube 3 20 , and the heating tube 1 18 , heating tube 2 19 and heating tube 3 20 are all arranged in a multi-bend structure.

[0037] Two baffle plates 28 are fixedly connected to the interior of the shell 1. The rear end of the baffle plate 28 at the left end is not connected to the rear end of the interior of the shell 1, and the front end of the baffle plate 28 at the right end is not connected to the front end of the interior of the shell 1. A plurality of fixing rings 22 are fixedly connected to the surfaces of the heating tube 18, the heating tube 219 and the heating tube 3 20. The surface of each fixing ring 22 is fixedly connected to a connecting plate 23, and the connecting plates 23 are fixedly connected to the shell 1 and the baffle plate 28.

[0038] Furthermore, water flows into the interior of the shell 1 and flows in the heating tube 1 18, the heating tube 2 19 and the heating tube 3 20. At the same time, the hot air enters the interior of the shell 1 through the rectangular groove 13. Due to the obstruction of the two blocking plates 28, the hot air can only flow to the rectangular groove 2 14 through the prescribed route, so that the hot air can stay longer in the heat exchanger. Since the heating tube 1 18, the heating tube 2 19 and the heating tube 3 20 have a multiple-bend structure, the water can stay longer in the heat exchanger, thereby improving the heat exchange efficiency.

[0039] See also Figure 5-Figure 7 The water inlet device includes a water inlet pipe 16, and the end of the water inlet pipe 16 close to the shell 1 is fixedly connected to a connecting pipe 17. The end of the connecting pipe 17 close to the shell 1 is set to three outlets, and the three outlets are respectively fixedly connected to heating pipe 18, heating pipe 2 19 and heating pipe 3 20.

[0040] The left end of the shell 1 is fixedly connected to a water outlet pipe 21, and the water outlet pipe 21 is set with three outlets at one end close to the shell 1. The three outlets are respectively fixedly connected to the heating tube 18, the heating tube 2 19 and the heating tube 3 20. The lower end of the shell 1 is symmetrically fixedly connected to two horizontal plates 25, and the lower end of each horizontal plate 1 25 is symmetrically fixedly connected to two support plates 26. The lower ends of the two support plates 26 located on the same horizontal plate 1 25 are fixedly connected to a horizontal plate 27.

[0041] Furthermore, water enters the connecting pipe 17 through the water inlet pipe 16, and is divided into three channels through the connecting pipe 17 and connected to the heating pipe 1 18, the heating pipe 2 19 and the heating pipe 3 20 respectively, and finally merges into one through the water outlet pipe 21. In the shell 1, the heating pipe 1 18, the heating pipe 2 19 and the heating pipe 3 20 are fixed in the shell 1 through the fixing ring 22 and the connecting plate 23. At the same time, the horizontal plate 1 25, the support plate 26 and the horizontal plate 2 27 support and fix the device.

[0042] The device also includes a PLC control system. An electric valve 24 is provided on the surface of the water inlet pipe 16. Temperature sensors are provided inside the air inlet pipe 2, the air outlet pipe 15 and the water outlet pipe 21. Flow meters are provided inside the heating pipe 18, the heating pipe 2 19 and the heating pipe 3 20.

[0043] Furthermore, the flue gas inlet temperature is set to T1, the flue gas outlet temperature is set to T2, the circulating water outlet temperature is set to T3, and the water circulation flow monitored by the flow meter is set to Q. The PID control algorithm is:

[0044] PLC according to the set value (T 2min =90°C) and the deviation of the measured T2, the electric valve 24 is dynamically adjusted to change the water flow Q. The adjustment formula is:

[0045] Q new =Q current +K P ·(T2-T 2min )+K I ·∫(T2-T 2min )dt;

[0046] K P : Proportional coefficient (fast response);

[0047] K I : Integral coefficient (eliminates steady-state error).

[0048] The PLC control system achieves dynamic adjustment by real-time monitoring of key parameters to ensure efficient and stable operation of the system. First, the system dynamically adjusts the water circulation flow rate according to the flue gas temperature. The system collects data in real time through temperature sensors installed at the flue gas inlet, outlet and circulating water outlet. Combined with the preset PID control algorithm, the electric valve (24) is automatically adjusted. When the flue gas outlet temperature is detected to be close to the set lower limit, the water flow rate is gradually reduced. If overtemperature occurs, the emergency cooling mechanism is triggered. This closed-loop control effectively balances heat recovery efficiency and equipment safety.

[0049] Through the above steps, the hot air passes through the diffuser 8 to reduce the hot air flow rate and diffuse the hot air at the same time. The hot air passes through the equalizer plate 12 to evenly enter the interior of the shell 1, so that the airflow is evenly distributed, the heat exchange efficiency is improved, and the aging of the material is reduced. At the same time, the flue gas inlet temperature, the flue gas outlet temperature and the circulating water outlet temperature are monitored in real time by the temperature sensor, and the electric valve 24 is controlled by the PLC in real time to adjust the water flow rate, thereby improving the heat energy recovery effect, so as to solve the problem that the airflow distribution of the existing waste heat recovery device is uneven, resulting in a decrease in heat exchange efficiency in local areas, and the high-temperature flue gas concentration on the other side may accelerate material aging and insufficient energy efficiency monitoring.

Claims

1. A heat energy recovery device for a thermal power plant, characterized by: The invention comprises an air inlet device, an air outlet pipe (15), a heat exchanger, a water inlet device and a water outlet pipe (21), wherein the rear end of the air inlet device is fixedly connected to the heat exchanger, the front end of the air outlet pipe (15) is fixedly connected to the heat exchanger, the left end of the water inlet device is fixedly connected to the heat exchanger, and the right end of the water outlet pipe (21) is fixedly connected to the heat exchanger.

2. A thermal energy recovery device for a thermal power plant according to claim 1, characterized in that: The air intake device comprises an air intake pipe (2), a connection frame (3) is fixedly connected to the surface of the air intake pipe (2), an air intake pipe (5) is provided at the rear end of the air intake pipe (2), a connection frame (4) is fixedly connected to the surface of the air intake pipe (5), and the connection frame (3) and the connection frame (4) are fixedly connected by multiple groups of bolts.

3. A thermal energy recovery device for a thermal power plant according to claim 2, characterized in that: The surface of the second air intake pipe (5) is fixedly connected with a connection frame (6), the rear end of the second air intake pipe (5) is provided with a diffuser (8), the surface of the diffuser (8) is fixedly connected with a connection frame (7), and the connection frame (6) and the connection frame (7) are fixedly connected by multiple groups of bolts.

4. The heat energy recovery device for a thermal power plant according to claim 3, characterized in that: The interior of the air inlet pipe 2 (5) is fixedly connected with filter screen 1 (9), filter screen 2 (10) and filter screen 3 (11), filter screen 1 (9) is made of metal fiber material, filter screen 2 (10) is made of P84 high temperature resistant fiber material, filter screen 3 (11) is made of activated carbon material, and the interior of the diffuser (8) is fixedly connected with a flow equalizing plate (12).

5. The heat energy recovery device for a thermal power plant according to claim 4, characterized in that: The heat exchanger comprises a shell (1), a rectangular groove (13) is provided on the left side of the front end of the shell (1), a rear end of the diffuser (8) is fixedly connected in the rectangular groove (13) of the shell (1), a rectangular groove (14) is provided on the right side of the rear end of the shell (1), and the rear end of the rectangular groove (14) of the shell (1) is fixedly connected to the outlet pipe (15).

6. The heat energy recovery device for a thermal power plant according to claim 5, characterized in that: The interior of the shell (1) is evenly provided with a heating tube 1 (18), a heating tube 2 (19) and a heating tube 3 (20), and the heating tube 1 (18), the heating tube 2 (19) and the heating tube 3 (20) are all arranged in a multi-bend structure.

7. The heat energy recovery device for a thermal power plant according to claim 6, characterized in that: Two baffle plates (28) are fixedly connected to the interior of the shell (1); the rear end of the baffle plate (28) at the left end is not connected to the rear end of the interior of the shell (1); the front end of the baffle plate (28) at the right end is not connected to the front end of the interior of the shell (1); a plurality of fixing rings (22) are fixedly connected to the surfaces of the heating tube 1 (18), the heating tube 2 (19) and the heating tube 3 (20); a connecting plate (23) is fixedly connected to the surface of each fixing ring (22); and the connecting plates (23) are fixedly connected to the shell (1) and the baffle plate (28).

8. The heat energy recovery device for a thermal power plant according to claim 7, characterized in that: The water inlet device comprises a water inlet pipe (16), one end of the water inlet pipe (16) close to the shell (1) is fixedly connected to a connecting pipe (17), and one end of the connecting pipe (17) close to the shell (1) is provided with three outlets, and the three outlets are respectively fixedly connected to heating pipe 1 (18), heating pipe 2 (19) and heating pipe 3 (20).

9. The heat energy recovery device for a thermal power plant according to claim 8, characterized in that: The left end of the shell (1) is fixedly connected to a water outlet pipe (21), and one end of the water outlet pipe (21) close to the shell (1) is provided with three outlets, and the three outlets are fixedly connected to the heating tube 1 (18), the heating tube 2 (19) and the heating tube 3 (20) respectively. The lower end of the shell (1) is symmetrically fixedly connected to two horizontal plates 1 (25), and the lower end of each horizontal plate 1 (25) is symmetrically fixedly connected to two support plates (26), and the lower ends of the two support plates (26) located on the same horizontal plate 1 (25) are fixedly connected to the horizontal plate 2 (27) together.

10. The heat energy recovery device for a thermal power plant according to claim 9, characterized in that: The device also includes a PLC control system, an electric valve (24) is provided on the surface of the water inlet pipe (16), temperature sensors are provided inside the air inlet pipe (2), the air outlet pipe (15) and the water outlet pipe (21), and flow meters are provided inside the heating pipe (18), the heating pipe (19) and the heating pipe (20).

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