Waste gas waste heat recycling device

Abstract

The utility model belongs to the technical field of waste gas preheating recycling, and particularly relates to a waste gas waste heat recycling device which comprises a barrel with a stirring assembly inside, a feeding channel and a discharging channel are arranged at the two ends of the barrel respectively, a waste gas channel is spliced to the outer side of the barrel through a cover body, and the stirring assembly is arranged in the barrel. The two ends of the cover body are connected with a gas inlet pipe and a gas outlet pipe which are communicated with the waste gas channel respectively, the barrel body comprises a first barrel body and a second barrel body, the gas inlet pipes of the first barrel body and the second barrel body are connected through a gas inlet header pipe, and the gas inlet header pipe is connected with the gas outlet header pipe. Humidity sensors are installed in the first barrel and the second barrel, and when the humidity sensor in any barrel detects that the humidity in the barrel is reduced to a preset threshold value, the controller closes the adjusting valve of the air inlet pipe corresponding to the barrel and synchronously opens the adjusting valve of the other barrel, so that uninterrupted heat exchange is achieved.

Description

Technical Field

[0001] This utility model belongs to the field of waste gas preheating and recovery technology, specifically relating to a waste gas waste heat recovery and reuse device. Background Technology

[0002] Currently, in the cement production industry, high-temperature exhaust gas from the kiln head is collected by bag filters at the kiln head and then directly discharged into the atmosphere through the kiln head exhaust fan into the chimney. The exhaust gas temperature is high, ranging from 70-80℃, and sometimes reaching around 100℃. There is no heat recovery device at this location, resulting in direct energy waste. Existing technology involves installing a drying chamber between the kiln head bag filter outlet and the kiln head exhaust fan inlet. This reduces the high-temperature exhaust gas temperature to around 25℃ before discharge, allowing for secondary heat recovery and utilization, reducing heat waste, protecting the ecological environment, and saving production costs.

[0003] However, in existing technologies, there is usually only one drying chamber installed between the kiln head bag dust collector outlet and the kiln head exhaust fan inlet. When the material in the drying chamber is drying, the dried material needs to be discharged before new material is added. However, if high-temperature exhaust gas is continuously transported into the drying chamber during the time the dried material is discharged, the temperature inside the drying chamber is still high and there is a lack of heat exchange medium. After the high-temperature exhaust gas is discharged from the drying chamber, the temperature is still high and does not meet the emission standards. It needs to be cooled again by cooling equipment. At the same time, it will also lead to the waste of heat energy of the high-temperature exhaust gas. Utility Model Content

[0004] To address the above problems, the purpose of this utility model is to provide a waste heat recovery and reuse device for exhaust gas, thereby solving the problems mentioned in the background art.

[0005] This utility model provides a waste heat recovery and reuse device for waste gas, including a cylinder with an internal stirring assembly. The cylinder has a feed channel and a discharge channel at its two ends, respectively. A waste gas channel is connected to the outer side of the cylinder via a cover. An inlet pipe and an outlet pipe, both connected to the waste gas channel, are respectively connected to the two ends of the cover. The device also includes a controller and a regulating valve installed on the inlet pipe. The cylinder comprises a first cylinder and a second cylinder. The inlet pipes of both the first and second cylinders are connected by a common inlet pipe. Humidity sensors are installed inside both the first and second cylinders. The output of the humidity sensor is connected to the signal input of the controller to provide the controller with the humidity signal of the material inside its respective cylinder. When the humidity sensor in either cylinder detects that the humidity inside the cylinder has decreased to a preset threshold, the controller closes the regulating valve of the corresponding inlet pipe of that cylinder and simultaneously opens the regulating valve of the other cylinder, achieving uninterrupted heat exchange.

[0006] Preferably, the ends of the two exhaust pipes are connected to a multi-stage spray cooling system. The cooling system includes at least two spray boxes connected in series. Each spray box is equipped with a spray head with an electric valve on its top. Multiple spray heads share a water supply system. Each exhaust pipe is equipped with a first temperature sensor for monitoring the primary cooling temperature of the exhaust gas. A second temperature sensor for monitoring the inter-stage cooling temperature is provided on the connecting pipe between the spray boxes. The signal output terminals of the first and second temperature sensors are both connected to the signal input terminal of the controller to provide the controller with the detected exhaust gas temperature. The controller adjusts the start / stop and flow rate of the spray heads in the corresponding spray box according to the signals transmitted by the first / second temperature sensors.

[0007] Preferably, a spiral guide plate is installed inside the exhaust gas passage, and the guide plate, together with the cover and the cylinder, forms a spiral gas guiding passage.

[0008] Preferably, the two feeding channels share a single unloading box, and the interior of the unloading box is divided into two unloading areas by a triangular cross-section partition block, with each unloading area corresponding to one of the two feeding channels.

[0009] Preferably, photoelectric sensors are installed in both feeding zones. These photoelectric sensors are used to detect whether there is material in their respective feeding zones. The signal output terminal of the photoelectric sensor is connected to the signal input terminal of the controller and is used to provide the controller with a signal indicating whether there is material in its respective feeding zone. The output terminal of the controller is used to issue a control signal, which is used to control the operating status of the regulating valve and stirring assembly in the first and second cylinders.

[0010] Preferably, two humidity sensors are provided in each of the cylinders.

[0011] The beneficial effects of this utility model are: the alternating operation of the two cylinders avoids the interruption of heat energy caused by the single cylinder shutdown for material replacement, thus improving the utilization rate of heat energy. At the same time, it can also prevent high-temperature exhaust gas from directly impacting the cylinder without material, reducing thermal stress damage to the cylinder. The installation of a humidity sensor inside the cylinder can monitor the moisture content of the material in real time, and the humidity threshold can be accurately triggered to switch, reducing the risk of over-drying or under-drying and improving the stability of product quality. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0013] Figure 2 This is a top view of the structure of this utility model;

[0014] Figure 3 This is a schematic diagram of the first cross-sectional structure of the present invention;

[0015] Figure 4This is a cross-sectional structural diagram of the cooling system in this utility model;

[0016] Figure 5 This is a schematic diagram of the second cross-sectional structure of the present invention.

[0017] In the diagram: 1. Mixing assembly; 2. Cylinder; 3. Feeding channel; 4. Discharge channel; 5. Cover; 6. Air inlet pipe; 7. Exhaust pipe; 8. Controller; 9. Regulating valve; 10. First cylinder; 11. Second cylinder; 12. Main air inlet pipe; 13. Humidity sensor; 14. Spray box; 15. Electric valve; 16. Water supply system; 17. First temperature sensor; 18. Second temperature sensor; 19. Discharge box; 20. Divider block; 21. Discharge area; 22. Photoelectric sensor; 23. Mixing rod; 24. Mixing paddle; 25. Motor; 26. Spray head; 27. Guide plate. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of this utility model in any way.

[0019] This utility model relates to an existing waste gas heat recovery and reuse device, which mainly includes a cylindrical body 2 for storing materials. The cylindrical body 2 is a cylindrical drying chamber with a length of 1 meter and a diameter of 0.3 meters, connected to the dust collection outlet duct of the kiln head bag. A stirring component 1 is installed inside the cylindrical body 2 to stir the materials during drying. One end of the cylindrical body 2 is connected to a feeding channel 3, and the other end is connected to a discharging channel 4. The discharging channel 4 has a built-in valve. An exhaust gas channel is spliced ​​on the outside of the cylindrical body 2 through a cover 5. The exhaust gas channel is connected to an air inlet pipe 6 connected to the dust collection outlet of the kiln head bag and an exhaust pipe 7 for discharging low-temperature exhaust gas on both sides. When the high-temperature exhaust gas after dust removal enters the exhaust gas channel along the air inlet pipe 6, it heats the cylindrical body 2 through heat exchange, thereby drying the materials inside the cylindrical body 2. Then the exhaust gas is discharged along the exhaust pipe 7. The above is an introduction to the existing waste gas heat recovery and reuse device.

[0020] As can be seen from the above, the existing waste heat recovery and reuse device for exhaust gas has the following defects when in use: there is usually only one drying chamber (cylinder 2) installed between the kiln head bag dust collector outlet and the kiln head exhaust fan inlet. When the material in the drying chamber (cylinder 2) is drying, the dried material needs to be discharged before new material is added. However, if high-temperature exhaust gas is continuously transported into the drying chamber (cylinder 2) during the time of discharging the dried material, the temperature inside the drying chamber (cylinder 2) is high at this time, and there is a lack of heat exchange medium. After the high-temperature exhaust gas is discharged from the drying chamber (cylinder 2), the temperature is still high and does not meet the emission standards. It needs to be cooled again by a cooling device. At the same time, it will also lead to the waste of heat energy of the high-temperature exhaust gas. Based on the above problems, the present invention adopts the following improvement method to solve them.

[0021] like Figure 1-5As shown, a waste heat recovery and reuse device for exhaust gas differs from existing technologies in that it has two cylinders 2 (the number of cylinders 2 can be more than two depending on the actual situation), namely a first cylinder 10 and a second cylinder 11. The air inlet pipes 6 of both the first cylinder 10 and the second cylinder 11 are connected by a single main air inlet pipe 12, and both air inlet pipes 6 are equipped with regulating valves 9 to control the opening and closing of the air inlet pipes 6. Humidity sensors 13 are installed inside both the first cylinder 10 and the second cylinder 11 to detect the humidity inside the cylinder 2, indirectly reflecting the humidity level. The degree of material drying is determined by connecting the signal output terminal of the humidity sensor 13 to the signal input terminal of the controller 8. This connection provides the controller 8 with a signal indicating the humidity level of the material within its respective cylinder 2. When the humidity sensor 13 in any cylinder 2 detects that the humidity level has dropped to a preset threshold, the controller 8 closes the regulating valve 9 of the corresponding air inlet pipe 6 for that cylinder 2 and simultaneously opens the regulating valve 9 of the other cylinder 2, achieving uninterrupted heat exchange. A feeding box 19 is installed on the feeding channel 3 of the first cylinder 10 and the second cylinder 11. The interior of the feeding box 19 is traversed by three... The triangular dividing block 20 forms two feeding zones 21, which correspond to two feeding channels 3 respectively, facilitating the feeding of materials into the corresponding cylinders 2. Photoelectric sensors 22 connected to the controller 8 are installed in both feeding zones 21. Each photoelectric sensor 22 includes a light emitter mounted on one side of the feeding box 19 and a light receiver mounted on the opposite side of the feeding box 19. When the light receiver does not receive light emitted by the light emitter, it indicates that material has entered the feeding zone 21. When the light receiver can receive light... When the emitter emits light, it indicates that no material has entered the feeding area 21. Specifically, in use, the first cylinder 10 is first used to dry the material. When the material is conveyed to the feeding area 21 connected to the first cylinder 10 by a conveying device (such as a screw conveyor or conveyor belt), the material falls into the first cylinder 10 along the feeding channel 3. At this time, the light receiver does not receive the light emitted by the light emitter and transmits the signal to the controller 8. The controller 8 opens the regulating valve 9 connected to the first cylinder 10 and simultaneously activates the stirring assembly 1 (such as...) inside the first cylinder 10. Figure 5As shown, the stirring assembly 1 consists of a stirring rod 22 rotatably connected to the cylinder 2, stirring paddles 24 evenly arranged on the stirring rod 22, and a motor 25 for driving the stirring rod 22 to rotate. When the motor 25 drives the stirring rod 22 to rotate, it stirs the material, improving the material drying efficiency. The regulating valve 9 connected to the second cylinder 11 is closed, and the high-temperature exhaust gas enters the exhaust gas channel of the first cylinder 10 along the main intake pipe 12 and the intake pipe 6, where it exchanges heat with the first cylinder 10 to dry the material. Subsequently, the high-temperature exhaust gas flows along the exhaust... Pipe 7 discharges exhaust gas through the exhaust channel. When humidity sensor 13 detects that the humidity inside the first cylinder 10 has dropped to a preset threshold, controller 8 controls the discharge channel 4 of the first cylinder 10 to open, allowing the material to be discharged along the discharge channel 4. At the same time, controller 8 controls the conveying equipment (such as a screw conveyor or conveyor belt) to transport the material to the unloading area 21 connected to the second cylinder 11. At this time, the photoreceiver in the unloading area 21 does not receive the light emitted by the light emitter and transmits the signal to controller 8. Controller 8 then opens the regulating valve 9 connected to the second cylinder 11. Simultaneously, the stirring assembly 1 inside the second cylinder 11 is turned on, and the regulating valve 9 connected to the first cylinder 10 is turned off, thereby drying the material inside the cylinder 2. The alternating operation of the two cylinders 2 avoids the interruption of heat energy caused by the single cylinder stopping to change materials, improving the utilization rate of heat energy. At the same time, it can also avoid the direct impact of high-temperature exhaust gas on the cylinder 2 without material, reducing thermal stress damage to the cylinder 2. In order to increase the utilization rate of exhaust gas, a spiral guide plate 27 is installed inside the exhaust gas channel. The guide plate, the cover 5, and the cylinder 2 form a spiral air guiding channel, which not only prolongs the time of exhaust gas in the exhaust gas channel, but also avoids local overheating of the cylinder 2. In order to avoid the failure of the humidity sensor 13 inside the cylinder 2 affecting the stability of the entire material drying system, the number of humidity sensors 13 can be set to two. The two humidity sensors 13 are respectively installed at the upper part of both ends of the cylinder 2. When one humidity sensor 13 fails, the other humidity sensor 13 can take over the work. When both humidity sensors 13 are working normally, the controller 8 takes the average value of the two humidity sensors 13 to determine the degree of material drying.

[0022] Furthermore, such as Figure 1-2 As shown, during the material drying process, as the temperature of the cylinder 2 and the material increases, the heat exchange rate of the high-temperature exhaust gas also decreases, and the temperature of the exhaust gas discharged along the exhaust pipe 7 also increases. To prevent substandard exhaust gas from being discharged into the external environment, a multi-stage spray cooling system is connected to the ends of the two exhaust pipes 7. The cooling system includes at least two spray boxes 14 connected in series. Each spray box 14 is equipped with a spray head 26 with an electric valve 15. Multiple spray heads 26 share a single water supply system 16. Figure 4As shown, the water supply system 16 includes a water supply pipe connected to multiple spray heads 26. The inlet of the water supply pipe is connected to a water source (not shown in the figure). Each exhaust pipe 7 is equipped with a first temperature sensor 17 for monitoring the primary cooling temperature of the exhaust gas. A second temperature sensor 18 for monitoring the interstage cooling temperature is installed on the connecting pipe between two adjacent spray boxes 14. The signal output terminals of the first temperature sensor 17 and the second temperature sensor 18 are both connected to the signal input terminal of the controller 8 to provide the controller 8 with the detected exhaust gas temperature. The controller 8 adjusts the start / stop and flow rate of the spray heads 26 of the corresponding spray box 14 according to the signals transmitted by the first / second temperature sensors 18. Specifically, for example, there are two spray boxes 14, named the first spray box 14 and the second spray box 14. When the exhaust gas is discharged through the exhaust pipe 7 of the first cylinder 10, it first passes through the first temperature sensor 17 to detect the exhaust gas temperature. The primary cooling temperature is determined by the first temperature sensor 17. When the temperature detected by the first temperature sensor 17 exceeds the first preset temperature threshold but is less than the second preset temperature threshold, the spray head 26 on the first spray box 14 is opened, and the electric valve 15 of the spray head 26 is increased to spray and cool the exhaust gas entering the first spray box 14. When the cooled exhaust gas passes through the connecting pipe, it is then detected by the second temperature sensor 18. If the detected exhaust gas temperature is lower than the first preset temperature threshold, the exhaust gas is directly discharged from the outlet of the second spray box 14. If the detected exhaust gas temperature is between the first and second preset temperature thresholds and close to the first preset temperature threshold, the controller 8 opens the spray head 26 on the second spray box 14 again (the flow rate of the spray head 26 is in the standard state and is not increased or decreased) to ensure that the temperature drop of the exhaust gas after spraying is less than or equal to the first preset temperature threshold and meets the emission standard.

Claims

1. A waste heat recovery and reuse device for waste gas, comprising a cylinder (2) with an internal stirring assembly (1), wherein a feeding channel (3) and a discharging channel (4) are respectively provided at both ends of the cylinder (2), and a waste gas channel is spliced ​​to the outside of the cylinder (2) through a cover (5), wherein an air inlet pipe (6) and an exhaust pipe (7) communicating with the waste gas channel are respectively connected to both ends of the cover (5), characterized in that: It also includes a controller (8) and a regulating valve (9) installed on the air inlet pipe (6). The cylinder (2) includes a first cylinder (10) and a second cylinder (11). The air inlet pipes (6) of the first cylinder (10) and the second cylinder (11) are connected through a main air inlet pipe (12). Humidity sensors (13) are installed inside the first cylinder (10) and the second cylinder (11). The output end of the humidity sensor is connected to the signal input end of the controller (8) to provide the controller (8) with the humidity signal of the material in the cylinder (2). When the humidity sensor (13) in any cylinder (2) detects that the humidity in the cylinder (2) has dropped to a preset threshold, the controller (8) closes the regulating valve (9) of the air inlet pipe (6) corresponding to that cylinder (2) and simultaneously opens the regulating valve (9) of the other cylinder (2) to achieve uninterrupted heat exchange.

2. The waste heat recovery and reuse device according to claim 1, characterized in that: The ends of the two exhaust pipes (7) are connected to a multi-stage spray cooling system. The cooling system includes at least two spray boxes (14) connected in series. Each spray box (14) is equipped with a spray head (26) with an electric valve (15) on its top. Multiple spray heads (26) share a water supply system (16). Each exhaust pipe (7) is equipped with a first temperature sensor (17) for monitoring the primary cooling temperature of the exhaust gas. A second temperature sensor (18) for monitoring the interstage cooling temperature is provided on the connecting pipe between the spray boxes (14). The signal output terminals of the first temperature sensor (17) and the second temperature sensor (18) are connected to the signal input terminal of the controller (8) to provide the controller (8) with the detected exhaust gas temperature. The controller (8) adjusts the start / stop and flow rate of the spray head (26) of the corresponding spray box (14) according to the signal transmitted by the first / second temperature sensor (18).

3. The waste heat recovery and reuse device according to claim 1, characterized in that: The interior of the exhaust gas passage is equipped with a spiral guide plate, which together with the cover (5) and the cylinder (2) forms a spiral gas guiding passage.

4. The waste heat recovery and reuse device according to claim 1, characterized in that: The two feeding channels (3) share a feeding box (19). The inside of the feeding box (19) is divided into two feeding areas (21) by a triangular cross-section partition block (20). The two feeding areas (21) correspond to the two feeding channels (3) respectively.

5. The waste heat recovery and reuse device according to claim 1, characterized in that: Photoelectric sensors (22) are installed in both feeding zones (21). The photoelectric sensors (22) are used to detect whether there is material in their respective feeding zones (21). The signal output terminal of the photoelectric sensor (22) is connected to the signal input terminal of the controller (8) and is used to provide the controller (8) with a signal indicating whether there is material in its respective feeding zone (21). The output terminal of the controller (8) is used to issue a control signal. The control signal is used to control the operating status of the regulating valve (9) and the stirring assembly (1) in the first cylinder (10) and the second cylinder (11).

6. The waste heat recovery and reuse device according to claim 1, characterized in that: Two humidity sensors (13) are provided in each of the cylinders (2).

Images