Drying flue gas purification system

Abstract

The utility model provides a drying flue gas purification system. The drying flue gas purification system comprises a drying machine, a dust remover, a cooler, a chimney and a flue gas circulation unit. A dried flue gas outlet of the dryer is communicated with an inlet of the dust remover through a first flue, a purified gas outlet of the dust remover is communicated with a flue gas inlet of the cooler through a second flue, and a flue gas outlet of the cooler is communicated with the chimney through a third flue. The flue gas circulating unit comprises a circulating flue, an air inlet channel, a first induced draft fan, a heater and a hot air channel, one end of the air inlet channel communicates with the heater, the other end of the air inlet channel is connected with the first induced draft fan, one end of the circulating flue communicates with the second flue, and the other end of the circulating flue communicates with the end, close to the heater, of the air inlet channel; two ends of the hot air channel are respectively communicated with an outlet of the heater and a hot air inlet of the dryer. According to the flue gas purification device, efficient purification of the dried flue gas is achieved, and meanwhile energy consumption is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of flue gas treatment, and in particular to a drying flue gas purification system. Background Art

[0002] In production, materials often need to be dried before use. For example, in the metallurgical process, various materials such as concentrates, fluxes, solid fuels, various slags, etc., need to be dried before they can be put into the furnace.

[0003] Dryer is a common thermal equipment in industry and is widely used in the drying process. A large amount of drying fume will be generated during the drying process. These fumes mainly include water vapor, dust, and particulate matter. If these drying fumes are directly discharged into the atmosphere, it will cause great harm to the environment and human health. Utility Model Content

[0004] The present application provides a drying flue gas purification system to solve the above-mentioned problems mentioned in the background technology.

[0005] The present application provides a drying fume purification system, comprising: a dryer, a dust collector, a cooler, a chimney and a fume circulation unit. The drying fume outlet of the dryer is connected to the inlet of the dust collector through a first flue, the clean gas outlet of the dust collector is connected to the fume inlet of the cooler through a second flue, and the fume outlet of the cooler is connected to the chimney through a third flue.

[0006] The flue gas circulation unit includes a circulating flue, an air inlet channel, a first induced draft fan, a heater and a hot air channel. One end of the air inlet channel is connected to the heater, and the other end of the air inlet channel is connected to the first induced draft fan. One end of the circulating flue is connected to the second flue, and the other end of the circulating flue is connected to an end of the air inlet channel close to the heater. Both ends of the hot air channel are respectively connected to the outlet of the heater and the hot air inlet of the dryer.

[0007] A humidity meter is arranged at one end of the air inlet passage close to the heater, and a circulating flue gas valve is arranged on the circulating flue.

[0008] Optionally, a mixing structure is provided at the connection between the air inlet channel and the circulating flue, and the mixing structure includes a fixing rod, fan blades and bearings.

[0009] The fixing rod is arranged along the outer ring circumference of the bearing, one end of the fixing rod is connected to the inner wall of the air inlet channel, the other end of the fixing rod is fixedly connected to the outer ring of the bearing, and the fan blades are arranged along the inner ring circumference of the bearing.

[0010] Optionally, the first flue is connected to a pre-cooling unit, which includes a cooling air duct, a second induced draft fan and a first thermometer.

[0011] The cooling air duct is coaxially sleeved on the outer periphery of the first flue, the second induced draft fan is connected to one end of the cooling air duct, an air outlet is opened at the other end of the cooling air duct, and the first thermometer is connected to one end of the first flue close to the dust collector.

[0012] Optionally, the dust collector is a wet dust collector or a dry dust collector.

[0013] Optionally, a second thermometer is provided on the third flue, and a cooling medium valve is provided at the cooling medium inlet of the cooler.

[0014] Optionally, an activated carbon adsorption box is also connected between the second flue and the flue gas inlet of the cooler.

[0015] Optionally, the activated carbon adsorption box includes an upper box body and a lower box body with the same structure, and both ends of the upper box body and the lower box body are provided with a smoke inlet and a smoke outlet, the smoke inlet is connected to the second flue, and the smoke outlet is connected to the smoke inlet of the cooler, and an activated carbon layer is provided in the upper box body and the lower box body, and the smoke flow direction from the smoke inlet to the smoke outlet is perpendicular to the surface where the activated carbon layer is located.

[0016] The drying fume purification system provided in the present application realizes efficient purification of drying fume and has the following beneficial effects compared with the prior art:

[0017] (1) The present application realizes efficient purification of drying flue gas through the above scheme. A dust collector is set to remove dust and other particulate matter in the drying flue gas, and then the drying flue gas is cooled by a cooler, so that the water vapor in the drying flue gas is cooled and condensed into liquid water, which is then separated from the flue gas to obtain clean flue gas. The clean flue gas is discharged into the atmosphere through a chimney, which not only achieves the purpose of dust removal and cooling of the drying flue gas, but also solves the problem of direct discharge of drying flue gas and pollution to the atmosphere. By setting up a flue gas circulation unit, the flue gas circulation unit includes a circulating flue, an air inlet channel, a first induced draft fan, a heater and a hot air channel. A part of the dust-removing flue gas is transmitted to the air inlet channel through the circulating flue to preheat the air in the air inlet channel, so that the temperature of the air is initially increased, thereby reducing the output frequency of the subsequent heater for heating the air to a specified drying temperature, reducing the power consumption or heat medium consumption of the heater, not only reducing the consumption of thermal energy resources by the heater, but also a part of the flue gas is recycled through the circulating flue, and the amount of drying flue gas entering the cooler for cooling is reduced, thereby reducing the amount of cooling medium in the cooler, reducing the cold consumption, and having a good effect on reducing production costs.

[0018] (2) By setting up a mixing structure, the circulating flue gas entering the air inlet channel is mixed with the air in the air inlet channel, thereby improving the mixing uniformity of the air and the circulating flue gas, thereby making the air temperature rise evenly, avoiding uneven local air temperature distribution that leads to incomplete drying of moisture in the material to be dried. After mixing, the uniformity of air temperature distribution is improved, thereby improving the drying efficiency of the material to be dried.

[0019] (3) By setting up a pre-cooling unit, the drying flue gas from the dryer is pre-cooled before entering the dust collector, so that the temperature of the drying flue gas reaches the normal operating temperature that the dust collector can withstand, which plays a protective role for the dust collector, thereby enabling the drying flue gas purification system to operate stably for a long period of time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 A schematic diagram of the structure of a drying fume purification system provided in one embodiment of the present application;

[0022] Figure 2 A schematic diagram of a hybrid structure provided in one embodiment of the present application;

[0023] Figure 3 A schematic diagram of the structure of a pre-cooling unit provided in one embodiment of the present application;

[0024] Figure 4 A schematic diagram of the structure of an activated carbon adsorption box provided in one embodiment of the present application;

[0025] Description of reference numerals:

[0026] 1: dryer, 2: dust collector, 3: cooler, 4: chimney, 6: activated carbon adsorption box, 110: first flue, 210: second flue, 310: third flue, 311: second thermometer, 312: cooling medium valve, 410: circulating flue, 411: circulating flue gas valve, 420: air inlet channel, 421: humidifier, 430: first induced draft fan, 440: heater, 450: hot air channel, 510: cooling air duct, 520: second induced draft fan, 530: first thermometer, 610: upper box, 620: lower box, 631: smoke inlet, 632: smoke outlet, 640: activated carbon layer, 710: fixing rod, 720: fan blade, 730: bearing. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present application.

[0028] like Figure 1 As shown, the present application provides a drying fume purification system, comprising: a dryer 1, a dust collector 2, a cooler 3, a chimney 4 and a fume circulation unit. The drying fume outlet of the dryer 1 is connected to the inlet of the dust collector 2 through a first flue 110, the clean gas outlet of the dust collector 2 is connected to the fume inlet of the cooler 3 through a second flue 210, and the fume outlet of the cooler 3 is connected to the chimney 4 through a third flue 310.

[0029] The flue gas circulation unit includes a circulating flue 410, an air inlet channel 420, a first induced draft fan 430, a heater 440 and a hot air channel 450. One end of the air inlet channel 420 is connected to the heater 440, and the other end of the air inlet channel 420 is connected to the first induced draft fan 430. One end of the circulating flue 410 is connected to the second flue 210, and the other end of the circulating flue 410 is connected to an end of the air inlet channel 420 close to the heater 440. Both ends of the hot air channel 450 are respectively connected to the outlet of the heater 440 and the hot air inlet of the dryer 1.

[0030] A hygrometer 421 is provided at one end of the air inlet channel 420 close to the heater 440 , and a circulating flue gas valve 411 is provided on the circulating flue 410 .

[0031] Specifically, the drying flue gas is the waste flue gas obtained after the material to be dried is dried by the dryer 1, which includes water vapor, dust and other particulate matter. The dust collector 2 is used to remove dust and other particulate matter in the drying flue gas to obtain dust-free flue gas. The cooler 3 is used to cool the drying flue gas so that the water vapor in the drying flue gas is cooled and condensed into liquid water, and then separated from the flue gas to obtain clean flue gas. The clean flue gas is discharged into the atmosphere through the chimney 4, which not only achieves the purpose of dust removal and cooling of the drying flue gas, but also solves the problem of direct discharge of drying flue gas and pollution to the atmosphere. The flue gas circulation unit is used to mix the dust-free flue gas that has passed through the dust collector 2 with the air used as the drying carrier of the dryer 1, and then heat the mixed gas through the heater 440 and send it into the dryer 1 to dry the material to be dried. The air is preheated by the flue gas circulation unit, and the power consumption of the heater 440 of the dryer 1 for heating the air is reduced, which has a good promoting effect on saving electricity and reducing the production cost of the enterprise.

[0032] When the dryer 1 is drying, the air is heated by the heater 440 to obtain high-temperature air, and the high-temperature air is used as a drying carrier to contact the material to be dried, and heat exchange occurs, so that the moisture in the material to be dried is heated to form water vapor and then discharged with the high-temperature air, so that the moisture in the material to be dried is taken away to achieve the purpose of drying. Therefore, the drying flue gas is a high-temperature flue gas containing water vapor and dust. After the drying flue gas is dedusted by the dust collector 2, although the temperature is reduced to a small extent, it is still a drying flue gas with a certain temperature. Therefore, the drying flue gas after dedusting by the dust collector 2 is reused, so that the heat in the flue gas can be utilized, while reducing the power output of the heater 440.

[0033] The flue gas circulation unit includes a circulating flue 410, an air inlet channel 420, a first induced draft fan 430, a heater 440 and a hot air channel 450. The dried flue gas passes through the dust collector 2, collects and settles the dust and other particulate matter therein, separates the particulate matter from the flue gas, and is transported to the cooler 3 through the second flue 210 for cooling. The circulating flue 410 is connected to the second flue 210, and a part of the flue gas after dust removal is transported to the air inlet channel 420 through the circulating flue 410, so that the air in the air inlet channel 420 is mixed with the flue gas in the circulating flue 410, and heat exchange is performed, thereby increasing the temperature of the air in the air inlet channel 420 to obtain a premixed gas, and then the premixed gas is transported to the heater 440 for heating to obtain hot air, and the hot air is transported to the dryer 1 through the hot air channel 450 as a drying carrier to contact and mix with the material to be dried, and mass and heat transfer are performed at the same time, and the moisture in the material to be dried is heated to generate water vapor and output with the hot air to obtain the dried material. By transmitting a portion of the dust removal flue gas to the air inlet channel 420 through the circulating flue 410, the air in the air inlet channel 420 is preheated, so that the temperature of the air is initially increased, thereby reducing the output frequency of the subsequent heater 440 for heating the air to the specified drying temperature, reducing the power consumption or heat medium consumption of the heater 440, not only reducing the consumption of thermal energy resources by the heater 440, but also a portion of the flue gas is recycled through the circulating flue 410, and the amount of drying flue gas entering the cooler 3 for cooling is reduced, thereby reducing the amount of cooling medium in the cooler 3, reducing the cold consumption, and having a good effect on reducing production costs.

[0034] The first induced draft fan 430 is used to provide power to input air into the heater 440 for heating. At the same time, the frequency of the first induced draft fan 430 is adjusted to adjust the amount of air input. The hygrometer 421 is used to detect the moisture content of the premixed gas entering the heater 440. The circulating smoke valve 411 is used to adjust the amount of smoke entering the air inlet channel 420. When the humidity value of the hygrometer 421 is greater than or equal to the preset humidity, the opening of the circulating smoke valve 411 is reduced, or the frequency of the first induced draft fan 430 is increased to reduce the content of the circulating smoke in the premixed gas, thereby reducing the humidity of the premixed gas, so that the premixed gas meets the conditions for drying the material to be dried in the dryer 1 after being heated by the heater 440.

[0035] The present application realizes efficient purification of drying flue gas through the above scheme. Dust and other particulate matter in the drying flue gas are removed by setting a dust collector, and the drying flue gas is cooled by a cooler, so that the water vapor in the drying flue gas is cooled and condensed into liquid water, and then separated from the flue gas to obtain clean flue gas. The clean flue gas is discharged into the atmosphere through a chimney, which not only achieves the purpose of dust removal and cooling of the drying flue gas, but also solves the problem of direct discharge of drying flue gas and pollution to the atmosphere. By setting up a flue gas circulation unit, the flue gas circulation unit includes a circulating flue, an air inlet channel, a first induced draft fan, a heater and a hot air channel. A part of the dust-removing flue gas is transmitted to the air inlet channel through the circulating flue to preheat the air in the air inlet channel, so that the temperature of the air is initially increased, thereby reducing the output frequency of the subsequent heater for heating the air to a specified drying temperature, reducing the power consumption or heat medium consumption of the heater, not only reducing the consumption of thermal energy resources by the heater, but also a part of the flue gas is recycled through the circulating flue, and the amount of drying flue gas entering the cooler for cooling is reduced, thereby reducing the amount of cooling medium in the cooler, reducing the cold consumption, and having a good effect on reducing production costs.

[0036] like Figure 2 As shown, optionally, a mixing structure is provided at the connection between the air inlet channel 420 and the circulating flue 410 , and the mixing structure includes a fixing rod 710 , a fan blade 720 and a bearing 730 .

[0037] The fixing rod 710 is arranged along the outer circumference of the bearing 730 , one end of the fixing rod 710 is connected to the inner wall of the air inlet channel 420 , the other end of the fixing rod 710 is fixedly connected to the outer ring of the bearing 730 , and the fan blades 720 are arranged along the inner circumference of the bearing 730 .

[0038] Specifically, the mixing structure is used to mix the circulating flue gas entering the air inlet channel 420 with the air in the air inlet channel 420, thereby improving the mixing uniformity of the air and the circulating flue gas, thereby making the air temperature rise evenly, avoiding uneven local air temperature distribution that leads to incomplete drying of moisture in the material to be dried. After mixing, the uniformity of the air temperature distribution is improved, thereby improving the drying efficiency of the material to be dried.

[0039] The fixing rod 710 is used to fix the bearing 730 in the air inlet channel 420. The bearing 730 is used to connect the fan blade 720, and the fan blade 720 rotates with the inner ring of the bearing 730, so that the fan blade 720 stirs and mixes the air and the circulating flue gas, thereby improving the preheating efficiency of the air and then improving the drying efficiency of the material to be dried.

[0040] like Figure 3 As shown, optionally, the first flue 110 is connected to a pre-cooling unit, and the pre-cooling unit includes a cooling air duct 510, a second induced draft fan 520 and a first thermometer 530.

[0041] The cooling air duct 510 is coaxially sleeved on the outer periphery of the first flue 110, the second induced draft fan 520 is connected to one end of the cooling air duct 510, an air outlet is opened at the other end of the cooling air duct 510, and the first thermometer 530 is connected to one end of the first flue 110 close to the dust collector 2.

[0042] Specifically, the pre-cooling unit is used to pre-cool the drying flue gas from the dryer 1 before it enters the dust collector 2, so that the temperature of the drying flue gas reaches the normal operating temperature that the dust collector 2 can withstand, thereby protecting the dust collector 2, and enabling the drying flue gas purification system to operate stably for a long period of time.

[0043] The pre-cooling unit includes a cooling air duct 510, a second induced draft fan 520 and a first thermometer 530. The second induced draft fan 520 is used to generate suction to draw air into the cooling air duct 510. The cavity between the inner side of the cooling air duct 510 and the outer side of the first flue 110 is filled with low-temperature air from the second induced draft fan 520. This part of low-temperature air exchanges heat with the high-temperature drying flue gas in the first flue 110, so that the temperature of the high-temperature drying flue gas is reduced, and then the heated air in the cooling air duct 510 is output from the outlet of the cooling air duct 510 at one end close to the cooler 3. The pre-cooling unit not only completes the pre-cooling of the drying flue gas, but also avoids the damage of the high-temperature drying flue gas to the dust collector 2. At the same time, the pre-cooling unit is only composed of the cooling air duct 510 and the second induced draft fan 520, which is convenient to install, low in cost and low in energy consumption.

[0044] When the temperature detected by the first thermometer 530 is greater than the first preset temperature, the frequency of the second induced draft fan 520 is increased, and when the temperature detected by the first thermometer 530 is equal to or less than the first preset temperature, the frequency of the second induced draft fan 520 is stopped from being adjusted.

[0045] Optionally, the dust collector 2 is a wet dust collector or a dry dust collector.

[0046] Specifically, the dust and particulate matter in the dry flue gas are removed by a wet dust collector or a dry dust collector.

[0047] like Figure 1 As shown, optionally, a second thermometer 311 is provided on the third flue 310 , and a cooling medium valve 312 is provided at the cooling medium inlet of the cooler 3 .

[0048] Specifically, the second thermometer 311 is used to detect the temperature of the drying flue gas entering the chimney 4 in the third flue 310, and the cooling medium valve 312 is used to adjust the amount of cooling medium entering the cooler 3. When the temperature detected by the second thermometer 311 is greater than the second preset temperature, the opening of the cooling medium valve 312 is increased to increase the contact amount between the drying flue gas and the cooling medium, and further reduce the temperature of the drying flue gas, so that the temperature of the drying flue gas entering the chimney 4 in the third flue 310 is less than or equal to the second preset temperature. The second preset temperature is determined according to the actual working conditions.

[0049] like Figure 4 As shown, optionally, an activated carbon adsorption box 6 is further connected between the second flue 210 and the flue gas inlet of the cooler 3 .

[0050] Specifically, the activated carbon adsorption box 6 is used to adsorb trace amounts of organic matter in the drying flue gas, thereby avoiding the pollution of the atmosphere by the organic matter after being discharged.

[0051] Furthermore, the activated carbon adsorption box 6 is located between the circulating flue 410 and the cooler 3 on the second flue 210 .

[0052] Optionally, the activated carbon adsorption box 6 includes an upper box body 610 and a lower box body 620 with the same structure, and a smoke inlet 631 and a smoke outlet 632 are provided at both ends of the upper box body 610 and the lower box body 620, the smoke inlet 631 is connected to the second flue 210, and the smoke outlet 632 is connected to the smoke inlet of the cooler 3, and an activated carbon layer 640 is provided in the upper box body 610 and the lower box body 620, and the smoke flow direction from the smoke inlet 631 to the smoke outlet 632 is perpendicular to the surface where the activated carbon layer 640 is located.

[0053] Specifically, the activated carbon adsorption box 6 includes an upper box body 610 and a lower box body 620 of the same structure, and an activated carbon layer 640 is arranged in the upper box body 610 and the lower box body 620. After dust removal, the drying flue gas enters the upper box body 610 / lower box body 620 through the second flue 210 through the smoke inlet 631, and then passes through the activated carbon layer 640. The organic matter, colloid and other substances in the drying flue gas are adsorbed by the activated carbon, and then discharged into the cooler 3 through the smoke outlet 632. In this way, the drying flue gas is further purified, the purification efficiency of the drying flue gas is improved, and the drying flue gas discharged through the chimney 4 is pollution-free to the environment and harmless to the health of humans and animals. The flue gas flow direction from the smoke inlet 631 to the smoke outlet 632 is perpendicular to the surface where the activated carbon layer 640 is located, which helps the drying flue gas to contact the activated carbon layer 640 to the greatest extent, and further improves the adsorption of organic matter by the activated carbon.

[0054] Among them, the upper box body 610 and the lower box body 620 are used in a backup mode, which facilitates the cleaning and replacement of the activated carbon layer 640 during long-term operation without stopping the system operation, and has no effect on the continuous purification of the drying flue gas.

[0055] The technical solution of the present application is described in detail below with reference to specific embodiments.

[0056] The operation process of the drying flue gas purification system in this embodiment is as follows:

[0057] When the system starts to operate, the first induced draft fan 430 is turned on to provide power, and the air is input into the heater 440 through the air inlet channel 420 for heating to obtain hot air, and the hot air is input into the dryer 1 through the hot air channel 450 as a drying carrier to contact and mix with the material to be dried, and mass transfer and heat transfer are performed at the same time, and the moisture in the material to be dried is heated to generate water vapor and output with the hot air to obtain dried materials, and dried flue gas is obtained at the top outlet of the dryer 1. The dried flue gas is input into the dust collector 2 through the first flue 110, and the dust collector 2 removes the dust and other particulate matter in the dried flue gas to obtain dust-free flue gas. The dried flue gas after dust removal enters the upper box 610 / lower box 620 through the second flue 210 through the smoke inlet 631, and then passes through the activated carbon layer 640, and the organic matter, colloid and other substances in the dried flue gas are adsorbed by the activated carbon, and then discharged into the cooler 3 through the smoke outlet 632. The cooled dried flue gas is input into the chimney 4 through the third flue 310 for emptying. When the temperature detected by the second thermometer 311 is greater than the second preset temperature, the opening of the cooling medium valve 312 is increased to further reduce the temperature of the drying flue gas, so that the temperature of the drying flue gas entering the chimney 4 in the third flue 310 is less than or equal to the second preset temperature. The second preset temperature is determined according to actual working conditions.

[0058] When the drying flue gas is transported from the dryer 1 to the dust collector 2, it passes through the pre-cooling unit, and the second induced draft fan 520 generates suction to draw air into the cooling air duct 510. The cavity between the inner side of the cooling air duct 510 and the outer side of the first flue 110 is filled with low-temperature air from the second induced draft fan 520. This part of low-temperature air exchanges heat with the high-temperature drying flue gas in the first flue 110, so that the temperature of the high-temperature drying flue gas is reduced, and then the air in the cooling air duct 510 is output from the outlet of the cooling air duct 510 at one end away from the second induced draft fan 520. When the temperature detected by the first thermometer 530 is greater than the first preset temperature, the frequency of the second induced draft fan 520 is increased, so that the temperature detected by the first thermometer 530 is equal to or less than the first preset temperature, and the frequency of the second induced draft fan 520 is stopped.

[0059] Drying flue gas circulation: the circulating flue 410 is connected to the second flue 210, and a part of the dust-removed flue gas is transported to the air inlet channel 420 through the circulating flue 410, so that the air in the air inlet channel 420 and the flue gas in the circulating flue 410 are mixed under the stirring of the fan blades 720, and heat exchange is performed, thereby increasing the air temperature in the air inlet channel 420 to obtain a premixed gas, and then the premixed gas is transported to the heater 440 for heating to obtain hot air, and the hot air is transported to the dryer 1 through the hot air channel 450 as a drying carrier to contact and mix with the material to be dried, and mass transfer and heat transfer are performed at the same time, the moisture in the material to be dried is heated to generate water vapor that is output with the hot air to obtain the dried material. When the humidity value of the hygrometer 421 is greater than or equal to the preset humidity, the opening of the circulating smoke valve 411 is reduced, or the frequency of the first induced draft fan 430 is increased to reduce the content of the circulating smoke in the premixed gas, thereby reducing the humidity of the premixed gas, so that the premixed gas meets the conditions for drying the material to be dried in the dryer 1 after being heated by the heater 440.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A drying flue gas purification system, characterized in that: include: Dryer (1), dust collector (2), cooler (3), chimney (4) and flue gas circulation unit; The drying fume outlet of the dryer (1) is connected to the inlet of the dust collector (2) through a first flue (110), the clean gas outlet of the dust collector (2) is connected to the fume inlet of the cooler (3) through a second flue (210), and the fume outlet of the cooler (3) is connected to the chimney (4) through a third flue (310); The flue gas circulation unit comprises a circulating flue (410), an air inlet channel (420), a first induced draft fan (430), a heater (440) and a hot air channel (450); one end of the air inlet channel (420) is in communication with the heater (440); the other end of the air inlet channel (420) is connected to the first induced draft fan (430); one end of the circulating flue (410) is in communication with the second flue (210); the other end of the circulating flue (410) is in communication with one end of the air inlet channel (420) close to the heater (440); and both ends of the hot air channel (450) are respectively in communication with the outlet of the heater (440) and the hot air inlet of the dryer (1); A hygrometer (421) is provided at one end of the air inlet channel (420) close to the heater (440), and a circulating flue gas valve (411) is provided on the circulating flue (410).

2. The drying fume purification system according to claim 1, characterized in that: A mixing structure is provided at the connection between the air inlet channel (420) and the circulating flue (410), wherein the mixing structure comprises a fixing rod (710), a fan blade (720) and a bearing (730); The fixing rod (710) is arranged along the outer circumference of the bearing (730), one end of the fixing rod (710) is connected to the inner wall of the air inlet channel (420), the other end of the fixing rod (710) is fixedly connected to the outer ring of the bearing (730), and the fan blade (720) is arranged along the inner circumference of the bearing (730).

3. The drying fume purification system according to claim 1, characterized in that: The first flue (110) is connected to a pre-cooling unit, and the pre-cooling unit comprises a cooling air duct (510), a second induced draft fan (520) and a first thermometer (530); The cooling air duct (510) is coaxially sleeved on the outer periphery of the first flue (110); the second induced draft fan (520) is connected to one end of the cooling air duct (510); an air outlet is provided at the other end of the cooling air duct (510); and the first thermometer (530) is connected to one end of the first flue (110) close to the dust collector (2).

4. The drying fume purification system according to claim 1, characterized in that: The dust collector (2) is a wet dust collector or a dry dust collector.

5. The drying fume purification system according to claim 1, characterized in that: The third flue (310) is provided with a second thermometer (311), and the cooling medium inlet of the cooler (3) is provided with a cooling medium valve (312).

6. The drying fume purification system according to any one of claims 1 to 5, characterized in that: An activated carbon adsorption box (6) is also connected between the second flue (210) and the flue gas inlet of the cooler (3).

7. The drying fume purification system according to claim 6, characterized in that: The activated carbon adsorption box (6) comprises an upper box body (610) and a lower box body (620) of identical structure, a smoke inlet (631) and a smoke outlet (632) are provided at both ends of the upper box body (610) and the lower box body (620), the smoke inlet (631) is communicated with the second flue (210), the smoke outlet (632) is communicated with the smoke inlet of the cooler (3), and an activated carbon layer (640) is provided in the upper box body (610) and the lower box body (620), and the smoke flow direction from the smoke inlet (631) to the smoke outlet (632) is perpendicular to the surface where the activated carbon layer (640) is located.

Images