Flue gas high-efficiency heat energy recovery and white smoke elimination system

Abstract

The utility model relates to a kind of flue gas efficient heat energy recovery white smoke elimination system, belong to flue gas white smoke elimination technical field, including flue gas heat energy recovery device and boiler, flue gas heat energy recovery device is equipped with fresh air outlet, fresh air outlet connects docking pipeline, installs air valve A on the cross section of docking pipeline, air valve B is installed in the side of docking pipeline, air induction fan is installed in air induction pipe, air valve C is installed in the side of air induction pipe;Flue gas heat energy recovery device includes primary condensing regenerator, secondary condensing heat recovery device and tertiary condensing heat recovery device, tertiary condensing heat recovery device top is fixedly connected with air collector, condensing heat recovery EC fan A is installed in the side of secondary condensing heat recovery device, condensing heat recovery EC fan B is installed in the side of tertiary condensing heat recovery device;The utility model low energy consumption, simple and reliable process, it is convenient to maintain, the combination of flue gas white smoke elimination and heat energy recovery is realized, high-grade heat source can be recycled, degree of automation is high, truly realizes unmanned operation.

Description

Technical Field

[0001] This utility model relates to a high-efficiency heat energy recovery and whitening system for flue gas, belonging to the field of flue gas whitening technology. Background Technology

[0002] Flue gas whitening refers to the process of eliminating the "white plumes" formed by water vapor condensation in flue gas emitted from industrial production (such as power, chemical, steel, and waste incineration industries) through technical means. These white plumes not only affect visual perception but may also carry pollutants, posing potential risks to the environment and human health. Therefore, "whitening" has become an important part of environmental governance.

[0003] Existing methods for eliminating white smoke have the following shortcomings:

[0004] 1. Cooling and Condensation: This method involves artificially generating a cold source and requires a refrigeration unit. It uses electricity to cool the temperature, and the condenser regenerates the heat. This method has a large investment and energy consumption, and the high-grade heat source cannot be recovered and reused.

[0005] 2. Natural cold source: Generally, cold water sources such as rivers are used, which continuously consume water resources and the high-grade heat source cannot be recovered and reused.

[0006] 3. Electrostatic whitening: High-voltage electrostatic equipment is used, which has high energy consumption, high failure rate, and high risk factor. High-grade heat source cannot be recovered and reused.

[0007] 4. Air-to-air heat exchange and mixed air discharge: The large volume of mixed air is used to eliminate white pollution, but the high-grade heat source cannot be recovered and utilized because the air mixing process is required at the end, so it cannot be discharged into the chimney for high-altitude emission.

[0008] As can be seen from the above processes, the first three methods allow the flue gas to enter the chimney for high-altitude emission, but they have problems such as large investment, high energy consumption, and safety hazards, and the high-grade heat source cannot be recovered and utilized; the fourth method, which has low energy consumption, cannot enter the chimney for high-altitude emission, nor can the high-grade heat source be recovered and utilized. Utility Model Content

[0009] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a flue gas high-efficiency heat energy recovery and whitening system, which has the advantages of low energy consumption, high degree of automation, ability to recycle high-grade heat sources, and simplicity and reliability.

[0010] The flue gas high-efficiency heat energy recovery and whitening elimination system of this utility model includes a flue gas heat energy recovery device and a boiler; the flue gas heat energy recovery device includes a primary condenser regenerator, a secondary condenser heat recovery device, and a tertiary condenser heat recovery device, each with a plate heat exchanger installed inside; the primary condenser regenerator is installed above the secondary condenser heat recovery device, and the tertiary condenser heat recovery device is installed to one side of the secondary condenser heat recovery device; the secondary and tertiary condenser heat recovery devices are fixed above the condensate tank, and their bottoms are connected to the condensate tank; a wind collection box is fixedly connected to the top of the tertiary condenser heat recovery device, and the wind collection box is connected to the primary condenser regenerator through a U-shaped pipe.

[0011] Preferably, a condensing heat recovery EC fan A is installed on one side of the secondary condensing heat recovery unit, a condensing heat recovery EC fan B is installed on one side of the tertiary condensing heat recovery unit, and a fresh air inlet is provided on the other side of the secondary and tertiary condensing heat recovery units.

[0012] Preferably, the flue gas heat recovery device is equipped with a fresh air outlet, which is located on the secondary and tertiary condensing heat recovery units. The fresh air outlet is connected to a docking pipe, which is connected to the boiler's induced draft pipe. A damper A is installed on the cross-section of the docking pipe, and damper A is connected to the induced draft pipe. A damper B is installed on the side of the docking pipe, and damper B is connected to the outside atmosphere. An induced draft fan is installed in the induced draft pipe, and a damper C is installed on the side of the induced draft pipe. Damper C is located inside the boiler room and is connected to the atmosphere inside the boiler room. The air outlets of the condensing heat recovery EC fan A and the condensing heat recovery EC fan B are both connected to the induced draft pipe.

[0013] Preferably, the fresh air inlet is equipped with a fresh air filter for filtration.

[0014] Preferably, the primary condenser regenerator has a flue gas inlet at the top and a flue gas outlet on the side.

[0015] Preferably, an air flow meter A is installed on the connecting pipe, an air flow meter B is installed on the exhaust pipe, and a flue gas temperature sensor is installed on the air collection box; the air flow meter A, the air flow meter B, and the flue gas temperature sensor are all electrically connected to the control system.

[0016] The advantages of this utility model compared with the prior art are:

[0017] 1. Low energy consumption: Compared with traditional refrigeration and cooling, condensation and heat recovery processes and electrostatic whitening processes, this utility model only consumes electricity from the condensation heat recovery EC fan, which can reduce energy consumption by more than 40%.

[0018] 2. Simple and reliable process: The cooling, condensation and heat recovery and electrostatic whitening process involves a lot of equipment, has a high failure rate, and requires heavy maintenance and is relatively costly. Except for the condensation heat recovery EC fan, which is a moving part and requires regular maintenance, the rest of this utility model is a static structure, which has high reliability and is easy to maintain. It can effectively achieve the dual benefits of flue gas whitening and heat recovery.

[0019] 3. High-grade heat energy can be recycled; This utility model connects to the boiler through a fresh air exhaust pipe, which can effectively recover high-grade heat sources in high-temperature and high-humidity flue gas.

[0020] 4. High degree of automation: The flue gas heat recovery device of this utility model adopts an integrated structure. The operation of the condensation heat recovery EC fan is automatically adjusted by the flue gas temperature sensor; the high-temperature fresh air volume is adapted by automatically adjusting the linkage opening of air valve A, air valve B and air valve C by the air flow meter, truly realizing unmanned operation. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model;

[0022] Figure 2 This is the front view of the flue gas heat recovery device;

[0023] Figure 3 This is a top view of a flue gas heat recovery device.

[0024] In the diagram: 1. Flue gas heat recovery device; 11. U-shaped pipe; 12. Fresh air filter; 13. Primary condenser regenerator; 131. Plate heat exchanger; 132. Flue gas inlet; 133. Flue gas outlet; 14. Secondary condenser heat recovery unit; 141. Condensation heat recovery EC fan A; 15. Condensate tank; 151. Drain pipe; 16. Tertiary condenser heat recovery unit; 161. Condensation heat recovery EC fan B; 17. Air collection box; 171. Flue gas temperature sensor; 2. Air flow meter A; 3. Air flow meter B; 4. Exhaust fan; 5. Boiler; 6. Air valve C; 7. Exhaust duct; 8. Connecting pipe; 9. Air valve A; 10. Air valve B. Detailed Implementation

[0025] Example 1

[0026] like Figures 1-3As shown, the flue gas high-efficiency heat energy recovery and whitening elimination system described in this embodiment includes a flue gas heat energy recovery device 1 and a boiler 5. The flue gas heat energy recovery device 1 is provided with a fresh air outlet, which is located on the secondary condensing heat recovery unit 14 and the tertiary condensing heat recovery unit 16. The fresh air outlet is connected to a docking pipe 8, which is connected to the induced draft pipe 7 of the boiler 5. An air valve A9 is installed on the cross-section of the docking pipe 8, and the air valve A9 is connected to the induced draft pipe 7. An air valve B10 is installed on the side of the docking pipe 8, and the air valve B10 is connected to the outside atmosphere. An induced draft fan 4 is installed in the induced draft pipe 7, and an air valve C6 is installed on the side of the induced draft pipe 7. The air valve C6 is located in the boiler room and is connected to the atmosphere in the boiler room.

[0027] The flue gas heat recovery device 1 includes a primary condenser heat recovery unit 13, a secondary condenser heat recovery unit 14, and a tertiary condenser heat recovery unit 16. Each of the primary condenser heat recovery unit 13, the secondary condenser heat recovery unit 14, and the tertiary condenser heat recovery unit 16 is equipped with a plate heat exchanger 131. The primary condenser heat recovery unit 13 is installed above the secondary condenser heat recovery unit 14, and the tertiary condenser heat recovery unit 16 is installed on one side of the secondary condenser heat recovery unit 14. The primary condenser heat recovery unit 13, the secondary condenser heat recovery unit 14, and the tertiary condenser heat recovery unit 16 adopt a modular size for easy assembly, and each module can be replaced or replaced individually.

[0028] The secondary condensing heat recovery unit 14 and the tertiary condensing heat recovery unit 16 are fixed above the condensate tank 15, and the bottoms of the secondary condensing heat recovery unit 14 and the tertiary condensing heat recovery unit 16 are connected to the condensate tank 15; a drain pipe 151 for discharging condensate is provided on one side of the condensate tank 15.

[0029] The top of the three-stage condensing heat recovery unit is fixedly connected to an air collection box 17, which is connected to the first-stage condensing heat recovery unit 13 through a U-shaped pipe 11. A condensing heat recovery EC fan A141 is installed on one side of the second-stage condensing heat recovery unit 14, and a condensing heat recovery EC fan B161 is installed on one side of the third-stage condensing heat recovery unit 16. Fresh air inlets are provided on the other side of the second-stage condensing heat recovery unit 14 and the third-stage condensing heat recovery unit 16.

[0030] In this embodiment, the air outlets of the condensing heat recovery EC fan A141 and the condensing heat recovery EC fan B161 are both connected to the exhaust duct 7. A fresh air filter 12 is provided on the fresh air inlet. A flue gas inlet 132 is provided on the top of the primary condensing regenerator 13, and a flue gas outlet 133 is provided on the side of the primary condensing regenerator 13. An air flow meter A2 is installed on the connecting pipe 8, an air flow meter B3 is installed on the exhaust duct 7, and a flue gas temperature sensor 171 is installed on the air collection box 17. Air flow meters A2, B3, and the flue gas temperature sensor 171 are all electrically connected to the control system, which is model ACS-XH-10K.

[0031] Example 2

[0032] The flue gas high-efficiency heat energy recovery and whitening method described in this embodiment includes the following steps:

[0033] S1. High-temperature and high-humidity flue gas enters through flue gas inlet 132 of the first-stage condenser and regenerator 13, undergoes pre-cooling in the first-stage condenser and regenerator 13, and precipitates some condensate. The condensate flows to the lower condensate tank 15.

[0034] S2. The pre-cooled flue gas enters the secondary condensing heat recovery unit 14 downwards. At this time, the condensing heat recovery EC fan A141 draws in fresh air and performs forced convection heat exchange with the pre-cooled flue gas, which reduces the flue gas temperature for the second time and condenses water for the second time. The condensate flows to the lower condensate tank 15. At the same time, the fresh air is heated by the flue gas heat exchange. During the heat exchange, the flue gas and the fresh air do not mix or come into contact with each other.

[0035] S3. After the second cooling, the flue gas enters the three-stage condensing heat recovery unit 16. Fresh air is drawn in through the condensing heat recovery EC fan B161 and undergoes forced convection heat exchange with the pre-cooled flue gas again, reducing the flue gas temperature for the third time and condensing water for the third time. The condensate flows to the lower condensate tank 15, continuously reducing the water content of the flue gas. At the same time, it exchanges heat with the fresh air and raises its temperature. During the heat exchange, the flue gas and the fresh air do not mix or come into contact with each other.

[0036] S4. After three cooling cycles, the flue gas enters the air collection box 17 upwards, and then enters the first-stage condenser and regenerator 13 along the U-shaped pipe 11. It undergoes forced convection heat exchange with the newly entered high-temperature and high-humidity flue gas to raise the temperature. After reducing the relative humidity of the discharged flue gas to the maximum extent, it is discharged from the flue gas outlet 133 and then discharged into the atmosphere through the chimney to achieve the effect of eliminating whitening of the flue gas.

[0037] S5. The flue gas temperature sensor 171 installed in the air collection box 17 senses the flue gas temperature after three cooling cycles, and automatically adjusts the speed of the condensation heat recovery EC fan A141 and the condensation heat recovery EC fan B161 to prevent the flue gas condensate from freezing and causing ice blockage when the temperature is extremely low in winter, which would cause the device to fail.

[0038] Meanwhile, by controlling the opening of air valves A9, B10 and C6 through air flow meters A2 and B3 installed in the connecting pipe, an appropriate amount of high-temperature fresh air is introduced into boiler 5 to achieve the effect of heat energy recovery and utilization.

[0039] In step S5, the control methods for condensing heat recovery EC fan A141, condensing heat recovery EC fan B161, air valve A9, air valve B10, and air valve C6 are as follows:

[0040] Assuming the suction volume of the induced draft fan 4 is 10000 CMH, and the air volume design range of the condensing heat recovery EC fan A141 and the condensing heat recovery EC fan B161 is set to 3000-15000 CMH, then the total air volume of the two is 6000-30000 CMH.

[0041] During high-temperature operation in summer, due to the high outside air temperature and the small temperature difference between the flue gas and the outside air, in order to minimize the moisture content of the flue gas, the condensing heat recovery EC fan A141 and condensing heat recovery EC fan B161 operate at high air volume to improve heat exchange efficiency. When the air volume detected by the air flow meter A2 is greater than the set suction volume of the induced draft fan 4, the control system will automatically reduce the opening of the damper A9 and increase the opening of the damper B10 until the air volume detected by the air flow meter A2 reaches the set suction volume of the induced draft fan 4. At this time, the dampers A9 and B10 stop adjusting simultaneously, and the excess air volume is discharged into the atmosphere through the damper B10. During this process, the damper C6 remains closed.

[0042] During low-temperature operation in winter, due to the low ambient temperature and large temperature difference between the flue gas and the ambient air, when the flue gas temperature sensor 171 detects that the flue gas temperature is lower than the set value, in order to prevent the flue gas condensate from freezing inside the plate heat exchanger 131 and causing ice blockage at extremely low temperatures, the control system adjusts the condensing heat recovery EC fan A141 and condensing heat recovery EC fan B161 to operate at low air volume. When the air volume detected by the air flow meter A2 is less than the set air intake of the induced draft fan 4, the control system will automatically increase the opening of the air valve A9 and decrease the opening of the air valve B10 to ensure that the air volume meets the requirements of the induced draft fan 4.

[0043] If the outside air temperature is extremely low, the total output air volume of the condensing heat recovery EC fan A141 and the condensing heat recovery EC fan B161 will continue to decrease until the air volume of a single condensing heat recovery EC fan is less than 5000 CMH. At this time, the air valve A9 will be fully open and the air valve B10 will be fully closed. At this time, the total air volume in the exhaust pipe 7 will be less than 10000 CMH, which is still insufficient to meet the needs of the exhaust fan 4. When the air valve B is fully closed, the control system will automatically open the air valve C6 located inside the boiler room to supplement the air to the exhaust fan 4. The air valve C6 will stop operating and remain open until the air volume detected by the air flow meter B3 reaches the set air intake volume of the exhaust fan 4.

Claims

1. A high-efficiency heat recovery and whitening system for flue gas, characterized in that, The system includes a flue gas heat recovery device (1) and a boiler (5); the flue gas heat recovery device (1) includes a primary condenser regenerator (13), a secondary condenser heat recovery device (14), and a tertiary condenser heat recovery device (16), each of which is equipped with a plate heat exchanger (131); the primary condenser regenerator (13) is installed above the secondary condenser heat recovery device (14), and the tertiary condenser heat recovery device (16) is installed above the secondary condenser heat recovery device (14). The device (16) is installed on one side of the secondary condensing heat recovery unit (14); the secondary condensing heat recovery unit (14) and the tertiary condensing heat recovery unit (16) are fixed above the condensate tank (15), and the bottoms of the secondary condensing heat recovery unit (14) and the tertiary condensing heat recovery unit (16) are connected to the condensate tank (15); the top of the tertiary condensing heat recovery unit (16) is fixedly connected to the air collection box (17), and the air collection box (17) is connected to the primary condensing heat recovery unit (13) through the U-shaped pipe (11).

2. The flue gas high-efficiency heat energy recovery and whitening elimination system according to claim 1, characterized in that, A condensing heat recovery EC fan A (141) is installed on one side of the secondary condensing heat recovery unit (14), and a condensing heat recovery EC fan B (161) is installed on one side of the tertiary condensing heat recovery unit (16). A fresh air inlet is provided on the other side of the secondary condensing heat recovery unit (14) and the tertiary condensing heat recovery unit (16), and a fresh air filter (12) for filtration is provided on the fresh air inlet.

3. The flue gas high-efficiency heat energy recovery and whitening system according to claim 2, characterized in that, The flue gas heat recovery device (1) is equipped with a fresh air outlet, which is located on the secondary condensing heat recovery unit (14) and the tertiary condensing heat recovery unit (16). The fresh air outlet is connected to a docking pipe (8), which is connected to the induced draft pipe (7) of the boiler (5).

4. The flue gas high-efficiency heat energy recovery and whitening system according to claim 3, characterized in that, A damper A (9) is installed on the cross-section of the connecting pipe (8), and the damper A (9) is connected to the induced draft pipe (7); a damper B (10) is installed on the side of the connecting pipe (8), and the damper B (10) is connected to the outside atmosphere; an induced draft fan (4) is installed in the induced draft pipe (7), and a damper C (6) is installed on the side of the induced draft pipe (7); the damper C (6) is located in the boiler room and is connected to the atmosphere in the boiler room; the outlets of the condensing heat recovery EC fan A (141) and the condensing heat recovery EC fan B (161) are both connected to the induced draft pipe (7).

5. The flue gas high-efficiency heat energy recovery and whitening system according to claim 1, characterized in that, The first-stage condenser regenerator (13) is provided with a flue gas inlet (132) at the top and a flue gas outlet (133) on the side.

6. The flue gas high-efficiency heat energy recovery and whitening system according to claim 4, characterized in that, An air flow meter A (2) is installed on the connecting pipe (8), an air flow meter B (3) is installed on the exhaust pipe (7), and a flue gas temperature sensor (171) is installed on the air collection box (17). The air flow meter A (2), the air flow meter B (3) and the flue gas temperature sensor (171) are all electrically connected to the control system.

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