Flue gas waste heat recovery device of forging heating furnace

Abstract

The utility model belongs to the field of heat exchange, and discloses a flue gas waste heat recovery device of a forging heating furnace, which comprises more than two identical heat accumulating type forging heating furnaces, and further comprises a first flue gas waste heat recovery device and a second flue gas waste heat recovery device which are matched with the heating furnaces and connected with each other, the first smoke waste heat recovery device comprises a first smoke exhaust pipeline, and a high-temperature smoke filter, an induced draft fan, a sleeve type expansion joint, a heat exchanger and an air reversing valve which are sequentially connected with the first smoke exhaust pipeline, the lower part of the heat exchanger is connected with a first cold water pipeline, and the upper part of the heat exchanger is connected with a first hot water pipeline; a first smoke exhaust pipeline branch pipe and a first air pipeline are connected to the air reversing valve, the first air pipeline is connected with an air blower, and gas pipelines, cold water pipelines and hot water pipelines of the first smoke waste heat recovery device and the second smoke waste heat recovery device are communicated with a main gas pipeline, a main cold water pipeline and a main hot water pipeline after being connected. Flue gas waste heat is fully utilized, and the energy utilization rate is increased.

Description

Technical Field

[0001] This utility model belongs to the field of heat exchange technology, specifically relating to a waste heat recovery device for flue gas from a forging heating furnace. Background Technology

[0002] Regenerative forging furnaces consume a large amount of energy during metal forging. The temperature of the billet inside the furnace often reaches over 1200 degrees Celsius. During the heating process, high-temperature flue gas is also generated. By recovering the waste heat from the flue gas through regenerator technology, energy efficiency can be significantly improved, and energy consumption and operating costs can be reduced. The regenerator flue gas waste heat recovery technology uses heat storage materials to absorb heat from the high-temperature flue gas and then transfer the heat to the combustion air and fuel gas entering the furnace. By periodically switching the flow direction of the flue gas and air, continuous heat recovery is achieved. The regenerator can improve the waste heat recovery efficiency of the flue gas to over 90%, significantly reducing fuel consumption. The preheated combustion air can increase the combustion temperature in the furnace, improve combustion efficiency, and reduce fuel consumption. By reducing fuel consumption, emissions of pollutants such as CO2 and NOx are reduced, thereby reducing production costs for enterprises and reducing thermal pollution to the environment.

[0003] However, even with a regenerative forging furnace, the exhaust gas temperature remains high, and a large amount of heat energy is still released into the atmosphere. In order to improve the utilization of waste heat from the flue gas and increase the recovery rate, and in line with the principles of energy conservation and emission reduction, it is necessary to make full use of the waste heat from the flue gas. Utility Model Content

[0004] In order to solve the above-mentioned technical problems, this utility model provides a waste heat recovery device for flue gas from forging heating furnaces. It transfers the waste heat of flue gas to cold water through a heat exchanger for heat exchange, which is highly efficient and energy-saving, reduces energy waste, and improves energy utilization.

[0005] The technical solution adopted by the utility model is as follows: a waste heat recovery device for the flue gas of a forging heating furnace, including two or more identical regenerative forging heating furnaces. Combustion nozzles are arranged on both sides of the hearth of the regenerative forging heating furnace. A regenerative chamber is arranged inside the combustion nozzle, and a regenerator is arranged inside the regenerative chamber. The gas inlets of the combustion nozzles are respectively connected to a gas pipeline, and a gas reversing valve is arranged on the gas pipeline. The air inlet of the regenerator is connected to an air pipeline. It also includes two identical sets of waste heat recovery devices for flue gas that are supporting the heating furnace, namely the first waste heat recovery device for flue gas and the second waste heat recovery device for flue gas. The waste heat recovery device for flue gas is connected to the end of the heating supply device. The first waste heat recovery device for flue gas is connected to the second waste heat recovery device for flue gas. The first waste heat recovery device for flue gas includes a first exhaust gas pipeline connected to the regenerative forging heating furnace, a high-temperature flue gas filter, an induced draft fan, a sleeve type expansion joint, a heat exchanger, an air reversing valve, and a fixed support arranged on the heat exchanger, which are connected in sequence to the first exhaust gas pipeline. A first cold water pipeline is connected to the lower part of the heat exchanger, and a first hot water pipeline is connected to the upper part. A first exhaust gas pipeline branch and a first air pipeline are connected to the air reversing valve. The first air pipeline is connected to a blower. The gas pipeline of the first waste heat recovery device for flue gas is connected to the gas pipeline of the second waste heat recovery device for flue gas and then connected to the main gas pipeline. The first cold water pipeline of the first waste heat recovery device for flue gas is connected to the cold water pipeline of the second waste heat recovery device for flue gas and then connected to the main cold water pipeline. The hot water pipeline of the first waste heat recovery device for flue gas is connected to the hot water pipeline of the second waste heat recovery device for flue gas and then connected to the main hot water pipeline, and then is transported to the heating end through a circulation pump. The exhaust gas pipeline branch of the first waste heat recovery device for flue gas is connected to the exhaust gas pipeline branch of the second waste heat recovery device for flue gas and then connected to the main flue and discharged into the atmosphere through a chimney.

[0006] Specifically, the fixed support is arranged at the lower part of the heat exchanger and is used to support the self-weight of the heat exchanger. The fixed support is composed of a horizontal plate, a vertical plate, a vertical rod, and a reinforcing rib. The two horizontal plates and the two vertical plates arranged on both sides of the horizontal plate are enclosed to form a frame. Four vertical rods are arranged under the frame, and reinforcing ribs are arranged between the vertical rods.

[0007] Specifically, the flue gas filter adopts a five-layer woven mesh structure, and the material is made of stainless steel, with a precision reaching - millimeters.

[0008] Specifically, the first exhaust gas pipeline is a high-temperature-resistant stainless steel pipeline. The outer of the flue gas pipe channel is wrapped with a ceramic fiber blanket heat insulation material, and the heat insulation material is fixed with high-temperature-resistant watering or straps.

[0009] Specifically, a temperature sensor is arranged on the main hot water pipeline to联动调节 (linkage adjustment) the rotation speed of the circulation pump to maintain the constant supply water temperature.

[0010] Specifically, the main hot water pipeline can be connected in parallel with other auxiliary heat sources through a mixing valve for auxiliary heating when the flue gas temperature is insufficient or when the boiler is shut down at night.

[0011] Specifically, a condensate collection tank is installed at the bottom of the heat exchanger. The acidity of the condensate can be monitored by monitoring the pH value of the condensate, and the condensate is discharged into the sewer after treatment.

[0012] The beneficial effects of this utility model are as follows: This utility model utilizes a heat storage forging heating furnace to connect a heat exchanger to a flue gas duct. The hot and cold water pipes installed on the heat exchanger fully utilize the waste heat of the flue gas through heat exchange. The hot water pipes are connected to the heating terminal and can also be used for heating in conjunction with other heat sources. This method of recovering and utilizing waste heat from the flue gas is highly efficient and energy-saving, improves energy utilization, and reduces the emission of pollutants such as CO2 / NOx in the flue gas, thereby reducing production costs for enterprises and reducing thermal pollution to the environment. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the present invention;

[0014] The diagram shows: 1. Regenerative forging furnace; 2. Combustion nozzle; 3. Regenerator chamber; 4. Regenerator body; 5. Gas pipeline; 501. Gas pipeline for the second flue gas recovery device; 51. Main gas pipeline; 6. Air pipeline; 601. First air pipeline; 7. Flue gas waste heat recovery device; 71. First flue gas waste heat recovery device; 72. Second flue gas waste heat recovery device; 8. First exhaust pipe; 9. High-temperature flue gas filter; 10. Exhaust fan; 11. Sleeve type Expansion joint; 12 Heat exchanger; 13 Air reversing valve; 14 Fixed bracket; 15 First cold water pipe; 1501 Second flue gas waste heat recovery device cold water pipe; 151 Main cold water pipe; 16 First hot water pipe; 1601 Second flue gas waste heat recovery device hot water pipe; 161 Main hot water pipe; 17 First exhaust pipe branch; 1701 Second flue gas waste heat recovery device exhaust pipe branch; 171 Main flue; 18 Blower. Detailed Implementation

[0015] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0016] like Figure 1As shown in the figure, a waste heat recovery device for the flue gas of a forging heating furnace includes more than two identical regenerative forging heating furnaces 1. Combustion nozzles 2 are arranged on both sides of the hearth of the regenerative forging heating furnace 1. A regenerator chamber 3 is arranged inside the combustion nozzle 2, and a regenerator body 4 is arranged inside the regenerator 3. The gas inlets of the combustion nozzles 2 are respectively connected to a gas pipeline 5. A gas change-over valve is arranged on the gas pipeline 5. The air inlet of the regenerator body 4 is connected to an air pipeline 6. It also includes two identical waste heat recovery devices 7 for the flue gas that are matched with the heating furnace, namely the first waste heat recovery device 71 and the second waste heat recovery device 72. The waste heat recovery device 7 is connected to the end of the heating supply device. The first waste heat recovery device 71 is connected to the second waste heat recovery device 72. The first waste heat recovery device 71 includes a first exhaust gas pipeline 8 connected to the regenerative forging heating furnace 1, a high-temperature flue gas filter 9, an induced draft fan 10, a sleeve type expansion joint 11, a heat exchanger 12, an air change-over valve 13, and a fixed support 14 arranged on the heat exchanger 12 that are sequentially connected to the first exhaust gas pipeline 8. A first cold water pipeline 15 is connected to the lower part of the heat exchanger 12, and a first hot water pipeline 16 is connected to the upper part of the heat exchanger l2. A first exhaust gas pipeline branch 17 and a first air pipeline 601 are connected to the air change-over valve 13. The first air pipeline 601 is connected to a blower 18. The gas pipeline 5 of the first waste heat recovery device is connected to the gas pipeline 501 of the second waste heat recovery device and then communicates with the main gas pipeline 51. The first cold water pipeline 15 of the first waste heat recovery device is connected to the cold water pipeline 1501 of the second waste heat recovery device and then communicates with the main cold water pipeline 151. The hot water pipeline 16 of the first waste heat recovery device is connected to the hot water pipeline 1601 of the second waste heat recovery device and then communicates with the main hot water pipeline 161 and is then transported to the heating end through a circulation pump. The exhaust gas pipeline branch 17 of the first waste heat recovery device is connected to the exhaust gas pipeline branch 1701 of the second waste heat recovery device and then communicates with the main flue 171 and is then discharged into the atmosphere through a chimney.

[0017] Preferably, the fixed support 14 is arranged at the lower part of the heat exchanger 12 and is used to support the self-weight of the heat exchanger 12. The fixed support 14 is composed of a horizontal plate, a vertical plate, a vertical rod, and a reinforcing rib. The two horizontal plates and the two vertical plates arranged on both sides of the horizontal plate are surrounded to form a frame. Four vertical rods are arranged below the frame, and reinforcing ribs are arranged between the vertical rods.

[0018] Preferably, the flue gas filter 9 adopts a five-layer woven mesh structure, the material is made of 316 stainless steel, and the precision reaches 1 - 200 millimeters.

[0019] Preferably, the first exhaust gas pipeline 8 is a high-temperature resistant stainless steel pipeline. The outside of the flue gas channel is wrapped with a ceramic fiber blanket heat insulation material, and the heat insulation material is fixed with high-temperature resistant watering or straps.

[0020] Preferably, a temperature sensor is installed on the main hot water pipe 161 to adjust the speed of the circulating pump and maintain a constant water supply temperature.

[0021] Preferably, the main hot water pipe 161 is connected in parallel with other auxiliary heat sources through a mixing valve for auxiliary heating when the flue gas temperature is insufficient or when the boiler is shut down at night.

[0022] Preferably, the heat exchanger 12 is provided with a condensate collection tank at the bottom, and the acidity of the condensate can be monitored by monitoring the pH value of the condensate, and the condensate is discharged into the sewer after treatment.

[0023] During operation, when there are ten regenerative forging furnaces in the forging workshop, ambient temperature air is supplied by blower 18. As the air passes through the regenerator 4 of the regenerative forging furnace 1, it is rapidly heated to a high temperature, typically only about 100°C lower than the furnace temperature. The high-temperature air is then injected into the furnace, entraining combustion gases to form a high-temperature, oxygen-deficient (2%-20%) gas flow. The fuel burns in this oxygen-deficient atmosphere, transferring heat to the heated workpiece. Simultaneously, high-temperature flue gas flows out from the other side of the furnace, transferring heat to the regenerator 4. The cooled flue gas then passes through a high-temperature flue gas filter 9 and an induced draft fan 10. The system consists of a sleeve-type expansion joint 11, a heat exchanger 12, an air reversing valve 13, and a chimney that discharges into the atmosphere. When the air reversing valve 13 switches at a certain frequency, the burners on both sides are in an alternating state of heat storage and heat release, thereby achieving energy saving. The lower part of the heat exchanger 12 is connected to a first cold water pipe 15. After the flue gas passes through the heat exchanger 12, it heats the cold water. The hot water in the hot water pipe connected to the ten heating furnaces is collected and sent to the heating terminal through a circulation pump. It can also be used to work with other auxiliary heat sources such as electric heaters and gas boilers to provide heating when the flue gas temperature is insufficient or when the boiler is shut down at night.

Claims

1. A kind of forging heating furnace flue gas waste heat recovery device, including two or more identical regenerative forging heating furnace (1), regenerative forging heating furnace (1) hearth both sides are provided with combustion nozzle (2), combustion nozzle (2)It is provided with regenerator (3) in, regenerator (3) is provided with regenerator (4) in, the gas inlet of combustion nozzle (2)It is connected with gas pipeline (5) respectively, gas pipeline (5) is equipped with gas reversing valve, the air inlet of regenerator (4) is connected with air pipeline (6), it is characterized in that: Also including the same two sets of flue gas waste heat recovery device (7) matched with heating furnace, namely first flue gas waste heat recovery device (71) and second flue gas waste heat recovery device (72), the flue gas waste heat recovery device (7) is connected to the end of heating device, the first flue gas waste heat recovery device (71) is connected with the second flue gas waste heat recovery device (72), the first flue gas waste heat recovery device (71) includes the first exhaust pipe (8) connected with the regenerative forging heating furnace (1), the high-temperature flue gas filter (9) connected with the first exhaust pipe (8) in turn, the induced draft fan (10), the sleeve type expansion joint (11), the heat exchanger (12), the air reversing valve (13) and the fixed support (14) arranged on the heat exchanger (12), the lower part of the heat exchanger (12) is connected with the first cold water pipe (15), the upper part is connected with the first hot water pipe (16), the air reversing valve (13) is connected with the first exhaust pipe branch (17) and the first air pipe (601), the first air pipe (601) is connected with the air blower (18), the gas pipe (5) of the first flue gas waste heat recovery device (71) is connected with the second flue gas recovery device gas pipe (501) and is communicated with the total gas pipe (51), the first cold water pipe (15) of the first flue gas waste heat recovery device is connected with the second flue gas recovery device cold water pipe (1501) and is communicated with the total cold water pipe (151), the hot water pipe (16) of the first flue gas waste heat recovery device is communicated with the second flue gas waste heat recovery device hot water pipe (1601) and is communicated with the total hot water pipe (161) and is delivered to the heating end through the circulating pump, the exhaust pipe branch (17) of the first flue gas waste heat recovery device is connected with the second flue gas waste heat recovery device exhaust pipe branch (1701) and is communicated with the total flue (171) and is discharged into the atmosphere through the chimney.

2. A device for recovering waste heat from flue gases of a forging heating furnace according to claim 1, characterized in that: The fixed support (14) is arranged on the lower part of the heat exchanger (12) and is used for supporting the self weight of the heat exchanger (12), the fixed support (14) is composed of horizontal plates, vertical plates, vertical rods and reinforcing ribs, the two horizontal plates and the two vertical plates arranged on the two sides of the horizontal plates are enclosed to form a frame, four vertical rods are arranged under the frame, and reinforcing ribs are arranged between the vertical rods.

3. A device for recovering waste heat from flue gases of a forging heating furnace according to claim 1, characterized in that: The flue gas filter (9) adopts a five-layer woven mesh structure, the material is 316 stainless steel, and the precision reaches 1-200 mm.

4. The flue gas waste heat recovery device for a forging heating furnace according to claim 3, characterized by: The first exhaust pipe (8) is a high-temperature-resistant stainless steel pipe, the outer surface of the flue pipe channel is wrapped with ceramic fiber blanket heat insulation material, and high-temperature-resistant water or binding tape is used to fix the heat insulation material.

5. The flue gas waste heat recovery device for a forging heating furnace according to claim 4, characterized by: The total hot water pipe (161) is provided with a temperature sensor, which is connected to a circulating pump to maintain the constant temperature of the water supply.

6. A device for recovering waste heat from flue gas of a forging heating furnace according to claim 5, characterized in that The total hot water pipe (161) can be connected in parallel with other auxiliary heat sources through a mixing valve for auxiliary heating when the flue gas temperature is insufficient or the furnace is stopped at night.

7. The device for recovering waste heat from flue gas of a forging heating furnace according to claim 6, characterized in that: The bottom of the heat exchanger (12) is provided with a condensate water collecting tank, the acidity of the condensate water can be monitored by monitoring the PH value of the condensate water, and the treated condensate water is discharged into the sewer.

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