[0058] Example one:
[0059] Such as figure 1 with figure 2 As shown, the gas-based shaft furnace 500 includes a furnace body 510 and a material warehouse 520. The furnace body 510 is used for the reduction of iron-containing raw materials. The material warehouse 520 can add heat source materials to the furnace body 510. For example, the materials may be oxidized pellets. To provide heat during the raw material reduction process. It can be understood that during the reduction process, the top gas generated has a relatively high temperature, and the temperature of the top gas discharged from the exhaust port 511 is about 450°C.
[0060] The waste heat recovery device 100 can recover and utilize the heat of the top gas of the high temperature furnace discharged from the gas-based shaft furnace 500, so as to improve the energy utilization rate, save energy and protect the environment. Such as figure 1 with figure 2 As shown, the waste heat recovery device 100 includes: a heat exchange bin 10, a dust discharge device 20 and a plurality of gas channels 140.
[0061] Among them, such as figure 1 As shown, an exhaust port 511 is provided on the top wall of the gas-based shaft furnace 500, and high-temperature furnace top gas can be discharged from the exhaust port 511 to the outside of the gas-based shaft furnace 500. A filter 512 is provided at the exhaust port 511 to preliminarily filter the furnace top gas. The dust discharge device 20 is connected to the exhaust port 511, such as figure 1 As shown, the dust discharge device 20 has a gas inlet 210, a gas outlet 220, and a dust outlet 230. Wherein, the gas inlet 210 is in communication with the exhaust port 511 of the furnace body 510, and the pre-filtered top gas can enter the dust discharge device 20 from the gas inlet 210 for further dust removal processing.
[0062] Such as figure 1 As shown, after furnace top gas enters the dust discharge device 20, dust impurities settle in the dust discharge device 20. The inner bottom wall 240 of the dust discharge device 20 is formed as an inclined surface, and a dust outlet 230 is provided at the lowermost end near the inclined surface. A dust hopper 231 and a discharge valve 232 are provided below the dust outlet 230. Such as figure 1 As shown, the dust and impurities settle in the dust discharge device 20 and flow into the lower dust outlet 230 through the inclined inner bottom wall 240, and accumulate in the lower dust hopper 231 for centralized treatment. Finally, the dust can be removed by controlling the discharge valve 232 The impurities are discharged from the dust discharge device 20.
[0063] Such as figure 1 As shown, above the dust discharge device 20 (such as figure 1 A gas outlet 220 is provided in the vertical direction shown in the figure, and the gas outlet 220 is connected with an air duct 221. The high-temperature furnace top gas after dust removal and filtration can be discharged from the gas outlet 220 through the air duct 221 out of the dust discharge device 20.
[0064] Such as figure 1 As shown, a top gas inlet 110 is provided under the heat exchange bin 10, and the top gas inlet 110 is connected to the outlet of the dust discharge device 20, and is between the top gas inlet 110 and the gas outlet 220 of the dust discharge device 20 A fan 250 is connected. Driven by the fan 250, the high-temperature top gas discharged from the dust discharge device 20 from the gas outlet 220 can enter the heat exchange bin 10 from the top gas inlet 110. The top gas inlet 110 is also provided with a flow control valve with an adjustable opening to adjust the flow rate of the top gas entering the heat exchange warehouse 10.
[0065] Such as figure 1 As shown, a shunt chamber 150 and a top gas discharge chamber 160 are provided at intervals along the vertical direction of the heat exchange warehouse 10. The dividing chamber 150 is arranged below the heat exchange bin 10, and the dividing chamber 150 is in communication with the top gas inlet 110, and a nozzle 170 is provided at the connection between the dividing chamber 150 and the top gas inlet 110. A plurality of gas passages 140 are communicated above the branch chamber 150, and the plurality of gas passages 140 extend in the vertical direction and are arranged at intervals in the horizontal direction.
[0066] Wherein, the distance between the outer peripheral walls of two adjacent gas channels 140 is L, and L=200mm. Such as figure 1 As shown, an expansion section 141 is provided in the middle of the gas channel 140, and the pipe diameter of the expansion section 141 is larger than the pipe diameters at the upper and lower ends. The diameter of the gas passage 140 at the expansion section 141 is 200 mm, and the gas passage 140 has 20 rows. A smooth transition portion 142 is provided at the connection between the small pipe diameter section at the upper end of the gas channel 140 and the expansion section 141. The smooth transition portion 142 adopts a rounded corner processing technology, and the rounded angle is 120°-160°. Similarly, the same smooth transition portion 142 is provided at the connection between the small pipe diameter section at the lower end of the gas channel 140 and the expansion section 141. The upper part of the gas channel 140 communicates with the top gas discharge chamber 160, and the top gas discharge chamber 160 communicates with the top gas outlet 120.
[0067] Such as figure 1 As shown, the material bin 520 is arranged above the heat exchange bin 10. The upper end of the material bin 520 is provided with an opening 521 through which materials can be loaded into the material bin 520. A material inlet 101 is arranged above the heat exchange bin 10, and a distributor is arranged at the material inlet 101. The lower end of the material bin 520 is in communication with the material inlet 101 of the heat exchange bin 10. The heat exchange bin 10 has a material passing cavity 130 therein, and the lower end of the heat exchange bin 10 is provided with a material outlet 102. The upper end of the material passing cavity 130 is in communication with the material inlet 101, the lower end of the material passing cavity 130 is in communication with the material outlet 102, and the material outlet 102 is in communication with the shaft furnace below.
[0068] It should be noted that such as figure 1 As shown, the material in the material bin 520 enters the material passing cavity 130 from the material inlet 101, and the material is an oxidized pellet to be heated with a diameter of 6mm-16mm. The high temperature furnace top gas in the gas passage 140 exchanges heat in the passing cavity 130, and the temperature increases. The preheated material (temperature is about 441° C.) enters the gas-based shaft furnace 500 from the material outlet 102, and is further heated and burned to smelt the metal in the gas-based shaft furnace 500.
[0069] Such as figure 1 As shown, the high-temperature top gas (temperature about 450°C) discharged from the exhaust port 511 is first filtered through the filter 512, and the pre-filtered high-temperature top gas enters the dust discharge device 20 from the gas inlet 210 for dust removal For purification, insulation materials are arranged on the furnace wall of the dust discharge device 20 to heat the high-temperature furnace top gas. The main components of the top gas after dust removal are: H 2 (38.2%), CO (20.0%), CH 4 (1.9%), H 2 O(21.0%), CO 2 (16.4%), N 2 (2.5%). The high-temperature top gas after dust removal is discharged from the dust discharge device 20 from the gas outlet 220. Under the action of the fan 250, the top gas of the high temperature furnace is 666735Nm 3 The flow rate of /h enters the distribution chamber 150 from the top gas inlet 110, and is evenly distributed into each gas channel 140 through the nozzle 170. The high-temperature furnace top gas entering the gas channel 140 exchanges heat with the material in the material passing cavity 130 to transfer the heat to the material and preheat the material. Thus, the preheating of the top gas is recycled. After the heat exchange, the top gas (the temperature is reduced to about 150°C) is collected into the top gas discharge chamber 160 above, and finally is discharged from the heat exchange bin 10 through the top gas discharge port. Such as figure 1 As shown, an insulation layer 180 is provided on the peripheral wall of the heat exchange bin 10 to prevent the heat in the heat exchange bin 10 from being lost and cause energy waste.
[0070] It can be understood that the top gas exchanges heat with the material during the flow of the top gas along the gas channel 140 from bottom to top, and the temperature of different areas in the heat exchange bin 10 is different. Such as figure 1 As shown, at the bottom of the heat exchange bin 10, the temperature in the heat exchange bin 10 at the small diameter section of the gas channel 140 is about 441°C; in the middle of the heat exchange bin 10, the gas channel 140 is at the expansion section 141 in the heat exchange bin. The temperature in 10 is 153°C-445°C; in the upper part of the heat exchange bin 10, the temperature in the heat exchange bin 10 at the small pipe diameter section of the gas channel 140 is 30°C-150°C.
[0071] Thus, by providing the heat exchange bin 10 and the gas passage 140, the high-temperature top gas discharged from the exhaust port 511 of the furnace body 510 can exchange heat with the material in the passing cavity 130, thereby transferring heat to the material, The material entering the furnace body 510 is preheated. As a result, the waste heat of the top gas is reused, the pressure of the top gas scrubbing cooling section and the preheating section of the gas-based shaft furnace 500 is reduced, and the effect of energy saving and environmental protection is achieved. Moreover, the gas channel 140 extends in the up and down direction, which is beneficial to reduce the flow resistance of the material in the passing cavity 130 and facilitate the flow of the material in the passing cavity 130.
