Sintering system for recycling cold waste gas of sintering ring

Abstract

The utility model discloses a sintering system for recycling sintering ring cooling waste gas, which comprises a sintering machine and a ring cooling machine which are sequentially connected in series, a main body fan cover (1) is arranged above the sintering machine in a covering manner, and a cooling fan cover (9) is arranged on the ring cooling machine in a covering manner. And a medium-temperature waste gas outlet of the cooling fan cover (9) is respectively communicated with a front-section air inlet (201), a middle-section air inlet (301) and a rear-section air inlet (401) of the main body fan cover (1) through three independent waste gas recycling pipelines (901). According to the sintering ring cooling waste heat recovery device, waste heat recovery of sintering ring cooling medium-temperature and low-temperature waste gas is achieved at low cost and high efficiency, meanwhile, the discharge amount of the waste gas is remarkably reduced, meanwhile, the sintering working condition is greatly enhanced, and the quality of sintered ore products is remarkably improved.

Description

Technical Field

[0001] The utility model relates to metallurgical sintering and waste gas treatment technology, in particular to a sintering system for recycling sintering ring-cooling waste gas, belonging to the technical field of metallurgical sintering and waste gas treatment. Background Art

[0002] During the sintering process, the temperature of the sintered cake can reach 700-800℃ after being unloaded from the sintering machine. The physical sensible heat resources it carries are the most important part of the sintering waste heat resources. In the process of using air to cool the sintered ore, the temperature of the sintered ore drops below 150℃, and a large amount of hot air is generated. Generally, the temperature of the cooling exhaust gas in different parts of the sintering ring cooler is different. The temperature gradually decreases from the receiving end to the discharging end. It is generally divided into three sections: a high temperature zone with a temperature higher than 250℃, a medium temperature zone with a temperature of 150℃ to 250℃, and a low temperature zone with a temperature lower than 150℃.

[0003] In actual production, many companies have built supporting sintering waste heat recovery systems to utilize the high-temperature cooling waste gas of the ring cooler in the form of waste heat power generation. However, due to the low temperature of the cooling waste gas in the medium and low temperature sections, the boiler heat exchange can only produce low-parameter steam, and the waste heat utilization efficiency is low and the utilization cost is high; some companies even discharge the medium and low temperature waste gas directly through the chimney, which wastes resources and pollutes the environment. The existing utilization technology of medium and low temperature sintering cooling waste gas mainly includes direct waste heat utilization and return to the sintering material surface. For example, the patent document CN 106931792 B proposes a method and device for comprehensive utilization of waste gas from a ring cooler, in which the medium-temperature waste gas of 150-220°C is used for ORC low-temperature power generation through heat exchange, and the waste gas after utilization is used to return to the sintering process for hot air sintering, or it is mixed with the low-temperature cooling waste gas of the ring cooler of less than 150°C to form waste gas of about 100°C, and returned to the sintering machine trolley for hot air sintering. Patent document CN108731486A proposes a system and a method for recycling medium and low temperature exhaust gas in a ring cooler. A smoke hood is arranged above the sintering machine and connected to the smoke hood above the ring cooler. The medium and low temperature exhaust gas of 80℃ to 250℃ from the ring cooler is converted from being directly discharged into the atmosphere to being directly reused in the bed of the sintering machine, thereby replacing the air originally inhaled from the surrounding atmosphere by the sintering machine for the sintering of raw and auxiliary fuels, so as to make full use of the sensible heat in the medium and low temperature exhaust gas and eliminate the pollution of the atmospheric environment by direct discharge of dust-containing exhaust gas.

[0004] However, in the above technology, directly using the cooling exhaust gas from the medium and low temperature sections for boiler heat exchange can only produce low-parameter steam, and the waste heat preheating efficiency is low and the utilization cost is high. Returning the medium and low temperature exhaust gas to sintering instead of air can utilize the waste heat of the exhaust gas to a certain extent from an energy perspective. However, since the temperature of the cooling exhaust gas is much higher than that of air, the gas volume expands, resulting in an oxygen concentration lower than that of normal temperature air (about 310 mg / L), and the higher the temperature, the lower the oxygen concentration, resulting in a reduction in the amount of oxygen drawn into the sintering material layer, which is not conducive to fuel combustion and affects the quality of the sintered minerals. Therefore, the exhaust gas must be cooled to about 100°C before returning to the sintering process and then introduced into the sintering process, resulting in a low efficiency in utilizing the waste heat of the exhaust gas during the sintering process. Utility Model Content

[0005] In view of the problems in the prior art that the direct waste heat recovery and utilization of medium and low temperature waste gas in the sintering ring cooling waste gas is low in efficiency and cost, and the temperature must be lowered when returning to sintering, resulting in low waste heat utilization efficiency, the utility model provides a sintering system for recycling sintering ring cooling waste gas, by respectively sending the ring cooling waste gas into the sintering front section wind hood, middle section wind hood and rear section wind hood, and according to the sintering needs of the sintering front section, middle section and rear section materials, the sintering front section wind hood, middle section wind hood and rear section wind hood are simultaneously supplemented with oxygen or steam for waste heat utilization, so that oxygen-enriched hot air that can be directly used for the sintering front section material surface, oxygen-containing hot air that can be directly used for the sintering middle section material surface and steam-enriched hot air that can be directly used for the sintering rear section material surface are obtained at the same time, and high-parameter steam that can be directly used for power generation and industrial hot water that can be used from multiple sources are obtained in the waste heat utilization process. The utility model realizes the waste heat recovery of the low-temperature exhaust gas from the sintering ring cooling at low cost and high efficiency, significantly reduces the exhaust gas emission, greatly strengthens the sintering conditions, and significantly improves the quality of the sintered ore products.

[0006] In order to achieve the above technical objectives, the technical solutions adopted by the present utility model are specifically described as follows:

[0007] A sintering system for recycling sintering ring-cooling waste gas, the sintering system comprises a sintering machine and a ring cooler connected in series, a main air hood is provided above the sintering machine, a cooling air hood is provided above the ring cooler, and the medium-temperature waste gas outlet of the cooling air hood is respectively connected to the front air inlet, the middle air inlet and the rear air inlet of the main air hood through three independent waste gas recycling pipelines.

[0008] Preferably, the low-temperature exhaust gas outlet of the cooling air hood is connected to the medium-temperature section air inlet of the ring cooler through a circulating air duct.

[0009] Preferably, the air inlet ends of the three independent exhaust gas recycling pipes are connected to the medium-temperature exhaust gas outlet of the cooling air hood through a diverter valve.

[0010] Preferably, a first partition wall and a second partition wall are provided in the main air hood, and the main air hood is divided into an oxygen supply front chamber, an oxygen supply middle chamber, and a steam supply rear chamber along the running direction of the material by the first partition wall and the second partition wall. The front section air inlet is provided on the oxygen supply front chamber, and a front area oxygen nozzle is also provided above the interior of the oxygen supply front chamber. The middle section air inlet is provided on the oxygen supply middle chamber, and a middle area oxygen nozzle is also provided above the interior of the oxygen supply middle chamber. The rear section air inlet is provided on the steam supply rear chamber, and a rear area water mist nozzle is also provided above the interior of the steam supply rear chamber.

[0011] Preferably, the oxygen supply front chamber 2 is located above the 1 / 25 material surface and the 5 / 25 material surface behind the ignition furnace of the sintering machine. The oxygen supply middle chamber 3 is located above the 6 / 25 material surface and the 15 / 25 material surface behind the ignition furnace of the sintering machine. The steam supply rear chamber 4 is located above the 16 / 25 material surface and the 23 / 25 material surface behind the ignition furnace of the sintering machine.

[0012] Preferably, a steam superheat heat exchanger and a material surface radiation heater are also provided in the oxygen supplementation antechamber. The steam superheat heat exchanger is located below the oxygen nozzle in the anterior zone, and the material surface radiation heater is located below the steam superheat heat exchanger. One end of the steam superheat heat exchanger is connected to a steam drum arranged outside the main body wind hood through a pipeline, and the other end is connected to the inlet of the material surface radiation heater, and the outlet of the material surface radiation heater is connected to the steam inlet of the steam power generation device arranged outside the main body wind hood through a pipeline.

[0013] Preferably, an evaporative heat exchanger is also provided in the oxygen supplementation chamber, and the evaporative heat exchanger is located below the oxygen nozzle in the middle zone. Both ends of the evaporative heat exchanger are connected to the steam drum provided outside the main body wind hood through pipelines.

[0014] As a preference, an industrial water heat exchanger is also provided in the steam supplement rear chamber, and the industrial water heat exchanger is located below the water mist nozzle in the rear area. The inlet end of the industrial water heat exchanger is connected to the desalted water network in the plant area through a pipeline, and the outlet end is connected to the steam drum provided outside the main air hood through a pipeline or is connected to other hot water utilization networks in the plant area through a pipeline.

[0015] Preferably, the air inlet ends of the front zone oxygen nozzle and the middle zone oxygen nozzle are independently connected to the plant area oxygen network through pipelines.

[0016] Preferably, a front zone temperature sensor is also provided below the material surface radiation heater.

[0017] Preferably, a middle zone temperature sensor is further arranged below the evaporative heat exchanger.

[0018] Preferably, a rear zone temperature sensor and a steam concentration sensor are further provided below the industrial water heat exchanger.

[0019] In the present invention, the heights of the oxygen supplementation front chamber, the oxygen supplementation middle chamber and the steam supplementation rear chamber are independently 0.3-30m, preferably 1-25m, and more preferably 2-20m. The thickness of the main air hood is 0.1-50cm, preferably 1-40cm, and more preferably 1.5-30cm. The inner diameter of the exhaust gas recycling pipe is 1-500cm, preferably 5-400cm, and more preferably 10-300cm.

[0020] In the utility model, the annular cooling waste gas (mainly the annular cooling medium-temperature waste gas and the annular cooling low-temperature waste gas) is diverted according to the working condition requirements (for example, the distribution ratio is 20-45%: 25-60%: 30-55%, preferably 25-40%: 30-55%: 35-50%) and enters the front hood, middle hood and rear hood of the sintering machine respectively, and then oxygen and steam are supplemented according to the actual sintering working condition requirements. Specifically, the hot air finally entering the front section of the sintering material surface is oxygen-enriched hot air, the hot air entering the middle section of the sintering material surface is normal oxygen hot air (consistent with the oxygen content in the air), and the hot air entering the rear section of the sintering material surface is steam-rich hot air, thereby achieving zero emission of the medium and low-temperature waste gas from the sintering annular cooling and realizing the sintering production coupled with multiple advanced technologies such as oxygen-enriched sintering, hot air sintering, and steam-rich sintering, thereby eliminating the shortcomings of the existing hot air sintering technology and significantly improving the sintering product quality and pollutant process control level. In addition, by combining the waste heat recovery system of the sintering cooling exhaust gas with the sintering machine, the investment cost and space occupation of waste heat recovery are reduced.

[0021] In the utility model, the sintering ring cooling waste gas is preferably the cooling waste gas with a temperature of 200℃~300℃, which is returned as the cooling medium of the medium temperature section by the low temperature section flue gas of the sintering ring cooler during cooling of the sintering ore. Its working oxygen concentration is generally about 160~190mg / L, which is lower than the oxygen concentration of the air at normal temperature (about 310mg / L). If it is directly returned to the sintering for use, it will have an adverse effect on the sintering, and the waste heat recovery efficiency is also low. By recycling the low temperature waste gas as the cooling gas for the middle section of the ring cooling, on the one hand, the direct discharge of the low temperature waste gas can be completely avoided, and the temperature of the ring cooling medium temperature waste gas with an original temperature between 150℃~250℃ can be increased to 200℃~300℃, so as to achieve the enrichment of the sensible heat of the material, which is conducive to the efficient recovery of the subsequent heat; on the other hand, by fully or partially replacing the cold air entering the medium temperature section of the ring cooling, the total amount of cold air used for cooling by the ring cooler is significantly reduced, and then the output of hot waste gas is significantly reduced, and finally the heat discharged with the waste gas is also significantly reduced.

[0022] In the utility model, independent oxygen nozzles are used to supplement oxygen in the front section hood above the front section material surface of the sintering machine and the middle section hood above the middle section material surface, so that the oxygen concentration in the oxygen-rich hot air entering the sintering material surface is supplemented to ρ1 (mg / L), and the oxygen concentration in the oxygen-containing hot air is supplemented to ρ2 (mg / L); in the rear section hood above the rear section material surface of the sintering machine, a water mist nozzle is used to spray water mist for steam supplementation, so that the water vapor concentration in the steam-rich hot air entering the sintering material surface is increased to ρ3 (%). It should be noted that when oxygen is supplemented in the oxygen supplementation front chamber and the oxygen supplementation middle chamber, the oxygen concentration in the hot exhaust gas after oxygen supplementation is determined according to the exhaust gas temperature, the temperature of the exhaust gas finally entering the sintering material surface, and the content, including:

[0023] ρ1=ρ0×(1+γ)×(273.15+T2) / (273.15+T1) (1)

[0024] ρ2=ρ0×(273.15+T3) / (273.15+T1) (2)

[0025] In formula (1) and formula (2), ρ0 is the oxygen concentration in atmospheric pressure air, which is 310 mg / L. T1 is the temperature of this part of exhaust gas when it enters the front wind hood, °C. T2 is the temperature of oxygen-enriched hot air when it enters the sintering material surface, °C. T3 is the temperature of oxygen-containing hot air when it enters the sintering material surface, °C. γ is the oxygen enrichment coefficient, 0%<γ<30%.

[0026] In the present invention, generally, when entering the material surface of the front section of sintering, the oxygen concentration (ρ1) of the obtained oxygen-enriched hot air is 330-430 mg / L, preferably 350-420 mg / L, and its temperature (T2) is 180-220°C, preferably 190-210°C. When entering the material surface of the middle section of sintering, the oxygen concentration (ρ2) of the obtained oxygen-containing hot air is 310-330 mg / L, preferably 315-320 mg / L, and its temperature (T3) is 150-180°C, preferably 155-170°C. When entering the material surface of the rear section of sintering, the concentration of water vapor (ρ3) in the obtained steam-enriched hot air is 3.3-4.8%, preferably 3.5-4.5%, and its temperature is 100-130°C, preferably 105-120°C. That is to say, the utility model converts the ring-cooled medium and low temperature exhaust gas which is difficult to directly utilize into a variety of hot air which is easy to directly utilize through diversion of oxygen enrichment, oxygen supplementation, steam supplementation and other treatments, and can significantly improve the sintering quality.

[0027] In the utility model, in the front section of the sintering machine, oxygen-rich hot air obtained after heat exchange with oxygen-rich hot exhaust gas is used for oxygen-rich hot air sintering (oxygen concentration > 310 mg / L), and the high-parameter steam generated in the heat exchange process is transported to the steam power generation device for power generation, so as to realize efficient utilization of waste heat; in the middle section of the sintering machine, hot air sintering is carried out (oxygen concentration is about 310 mg / L) by using the oxygen-containing hot air obtained after heat exchange with oxygen-containing hot exhaust gas, and the low-parameter water vapor generated in the heat exchange process is transported to the steam superheat heat exchanger in the oxygen replenishing front chamber above the material surface of the front section of the sintering machine for the production of high-parameter water vapor; in the rear section of the sintering machine, steam-blowing sintering is carried out by using the steam-rich hot air obtained after heat exchange with steam-rich hot exhaust gas, and the industrial hot water generated in the heat exchange process is transported to the evaporative heat exchanger in the oxygen replenishing middle chamber above the material surface of the middle section for the production of low-parameter water vapor or returned to other production processes for use. That is, the utility model adopts a step-by-step heat exchange method to achieve efficient coupled utilization of the waste heat of each sintering waste gas, while improving the sintering environment and reducing the emission of waste gas and pollutants.

[0028] In the utility model, oxygen-enriched hot air, oxygen-containing hot air and steam-enriched hot air are respectively sent to the sintering front section, middle section and rear section of the sintering machine through the waste gas recycling pipeline to replace the normal temperature air and enter the sintering material layer to promote the sintering reaction. Among them, the sintering front section refers to the section of the 1 / 25 to 5 / 25 sections of the material surface between the sintering ignition point and the sintering end point; the sintering middle section refers to the section of the 6 / 25 to 15 / 25 sections of the material surface between the sintering ignition point and the sintering end point; the sintering rear section refers to the section of the 16 / 25 to 23 / 25 sections of the material surface between the sintering ignition point and the sintering end point. Sending oxygen-rich hot air into the material surface of the front section of sintering for oxygen-rich sintering and sending oxygen-containing hot air into the material surface of the middle section of sintering for hot air sintering can increase the upper limit of the allowable temperature of the hot air and realize the coupling of oxygen-rich sintering and hot air sintering, further optimize the sintering reaction process in the front and middle sections of sintering, and improve the quality indicators of sintered minerals; and sending steam-rich hot air into the material surface of the rear section of sintering for steam injection sintering, optimize the sintering reaction process in the middle and back ends of sintering, and improve the quality of sintered minerals.

[0029] In the utility model, the method and system of the utility model adopt technical means such as cascade utilization of low-temperature exhaust gas from comprehensive sintering ring cooling, synchronous oxygen supplementation and quality improvement of exhaust gas, cascade heat exchange, and selective steam supplementation to eliminate direct emission of low-temperature exhaust gas, and can use low-value coal gas combustion in steel plants to supplement heat and coordinate oxygen supplementation or oxygen-enriched combustion to increase the temperature of medium and low-temperature exhaust gases to meet the requirements of producing high-parameter steam while significantly increasing the oxygen and water vapor content in the exhaust gas. Further, high-quality steam and industrial hot water are produced through heat exchange and the flue gas temperature is reasonably controlled, so that the exhaust gas entering different sintering material surfaces contains a certain amount of oxygen and water vapor. By taking the above technical measures, firstly, the recovery of waste heat from medium and low temperature exhaust gas in sintering ring cooling is transformed from direct discharge or recovery of low parameter steam to recovery of high parameter steam, and the quality and efficiency of waste heat recovery are improved; secondly, oxygen and water vapor are selectively added to medium and low temperature waste gas at the same time to increase the oxygen concentration in the exhaust gas finally returned to sintering (≥ 310 mg / L of oxygen concentration in normal temperature air), so that when the exhaust gas temperature entering sintering is greater than 120°C, its oxygen content can still meet the needs of sintering reaction, eliminating the negative impact of thin oxygen at high temperature on the sintering process, and improving The utilization rate of waste heat from exhaust gas during the sintering process; thirdly, oxygen-rich hot air is transported to the material surface at the front stage of sintering for oxygen-rich sintering, oxygen-containing hot air is transported to the material surface at the middle stage of sintering for hot air sintering, and steam-rich hot air is transported to the material surface at the rear stage of sintering for steam-rich sintering. Compared with ordinary air, which contains both fuel gas and excess oxygen as well as some steam, the existing "oxygen-enriched sintering technology" and "material surface injection water vapor technology" are coupled together to superimpose the improvement effect on sintering. When the exhaust gas is used instead of air for sintering, the quality indicators of sintered minerals can be significantly improved and pollutant emissions can be reduced.

[0030] In the utility model, the sintering system for recycling sintering ring cooling waste gas includes a main hood, partition walls (first partition wall, second partition wall), oxygen supply front chamber, oxygen supply middle chamber, steam supply rear chamber, and a steam drum is arranged outside each chamber. The main hood is on the sintering trolley, replacing the conventional sintering machine hood, covering the position from sintering ignition to before the sintering end; two partition walls divide the main hood into three chambers (i.e. oxygen supply front chamber, oxygen supply middle chamber, steam supply rear chamber) along the movement direction of the sintering trolley, and each chamber is respectively provided with other matching heat exchange and oxygen supply, gas supply and other devices.

[0031] In the utility model, the oxygen supplying front chamber is located behind the sintering electric furnace, and is connected to the recycling pipeline of the ring cooling waste gas through the front air inlet, and part of the ring cooling waste gas enters the oxygen supplying front chamber; an oxygen nozzle is arranged below the front air inlet, and there are evenly distributed air outlet holes on the pipe wall, which can spray oxygen evenly in all directions to increase the oxygen concentration in the ring cooling waste gas, and its front end is connected to the oxygen pipe network in the factory area through a control valve; in the main part of the oxygen supplying front chamber below the oxygen nozzle, a steam superheat heat exchanger and a material surface radiation heater are continuously arranged from top to bottom; the front end of the steam superheat heat exchanger is connected to the steam drum, and the rear end is connected to the material The surface radiation heater is connected to the inlet of the surface radiation heater. Its main function is to use the waste heat of the exhaust gas to increase the temperature of the low-parameter water vapor generated in the subsequent step (oxygenation middle chamber). The surface radiation heater is distributed in a flat manner at a position close to the sintering material surface. Its surface has a heat-absorbing coating made of special materials, which can quickly absorb the heat radiation of the red fire layer of the material surface in a short period of time after sintering ignition, further increase the temperature of the steam, and finally obtain high-parameter steam and then transmit it to the steam power generation device at the rear end for use; the bottom of the oxygen supplementation front chamber is also provided with a front zone temperature sensor to monitor the temperature of the exhaust gas entering the material layer from then on. The function of the oxygen supplementation front chamber is to supplement oxygen and heat the ring-cooled exhaust gas entering the chamber, and at the same time, heat exchange the steam with the material surface radiation heating to obtain high-parameter steam with a temperature of ≥380℃ and a pressure of ≥1.6Mpa for power generation, while the exhaust gas temperature drops to 180℃~220℃, and the oxygen concentration increases to much greater than 310mg / L, and enters the sintering material layer for oxygen-enriched hot air sintering.

[0032] In the utility model, the oxygen supply middle chamber is adjacent to the rear of the oxygen supply front chamber and is separated by a partition wall. It is connected to the recycling pipeline of the ring-cooled exhaust gas through the middle air inlet, and part of the ring-cooled exhaust gas enters the oxygen supply middle chamber from this. An oxygen nozzle is also arranged below the middle air inlet, and there are evenly distributed air outlet holes on the pipe wall, which can spray oxygen evenly in all directions to increase the oxygen concentration in the ring-cooled exhaust gas. The front end is connected to the oxygen pipeline network of the plant through a control valve. An evaporative heat exchanger is also arranged in the main part of the oxygen supply middle chamber below the oxygen nozzle, and the front and rear ends of the evaporative heat exchanger are connected to the steam drum, which uses the waste heat of the ring-cooled exhaust gas to generate steam for evaporative heat exchange. A middle zone temperature sensor is also arranged at the bottom of the oxygen supply middle chamber to monitor the temperature of the exhaust gas entering the material layer from then on. The function of the oxygen replenishment chamber is to replenish oxygen and exchange heat for the ring-cooled exhaust gas entering the chamber, generate water vapor and transport it to the steam collecting device, while the exhaust gas temperature drops to 150℃~180℃, and the oxygen concentration increases to about 310mg / L, and enters the sintering material layer for oxygen replenishment hot air sintering.

[0033] In the utility model, the supplementary steam rear chamber is adjacent to the rear of the supplementary oxygen middle chamber and is separated by a partition wall. It is connected to the annular cooling exhaust gas recycling pipeline through the rear air inlet, and part of the annular cooling exhaust gas enters the supplementary steam rear chamber; a water mist nozzle is arranged below the rear air inlet, which sprays water mist upward in a countercurrent manner with the exhaust gas at a set flow rate, and uses the waste heat of the exhaust gas to quickly evaporate and vaporize the water mist droplets. The front end of the water mist nozzle is connected to the industrial hot water utilization pipeline network; the main part of the supplementary steam rear chamber below the water mist nozzle is also provided with an industrial water heat exchanger, the front end of which is connected to the desalted water pipeline network in the plant area, and the rear end of which is connected to the steam drum or the industrial hot water utilization pipeline network and other hot water utilization pipeline networks in the plant area. The function of the device is to use the industrial desalted water to exchange heat with the exhaust gas, and the generated hot water is respectively transported to the steam drum, the water mist nozzle and other hot water utilization pipeline networks in the plant area; a rear area temperature sensor and a steam concentration sensor are also arranged at the bottom of the supplementary steam rear chamber to monitor the exhaust gas temperature and steam concentration entering the material layer from then on. The function of the steam-supplemented rear chamber is to supplement steam, exchange heat and cool the annular cooling exhaust gas entering the chamber, generate industrial hot water with a temperature ≥90°C and transport it to subsequent and other utilization steps, while the exhaust gas temperature drops to 100°C ~ 130°C, and the steam concentration increases to 3.3% ~ 4.8%, and enters the sintering material layer for hot air steam injection sintering.

[0034] Compared with the prior art, the beneficial technical effects of the utility model are as follows:

[0035] 1: The system provided by the utility model transmits the sintering ring cooling waste gas to the wind hood above the sintering machine, combines the waste heat utilization of the waste gas with the advanced sintering technology, can not only realize the efficient utilization of the waste heat of the sintering ring cooling waste gas, but also obtain a variety of media for improving the sintering process: in terms of waste heat utilization, in the order of the sintering rear section, middle section and front section, the stepped heat exchange device installed in the sintering machine wind hood is used to respectively perform water heat exchange, hot water evaporation heat exchange and steam superheat heat exchange, and in the front section wind hood of the sintering, the high temperature after the ignition of the sintering material layer surface is used to heat the steam The steam is further radiated for heating to obtain high-parameter steam for power generation, thereby improving the utilization efficiency of waste heat. In terms of improving the sintering process, combined with the fact that the demand for heat and oxygen in the sintering process gradually decreases from the front end to the back end, the oxygen-enriched sintering and steam injection sintering technologies are coupled. In the process of utilizing the waste heat from exhaust gas, oxygen-enriched hot air, oxygen-supplemented hot air, and steam-enriched hot air with gradually decreasing temperature and oxygen concentration are obtained from front to back respectively. Oxygen-enriched hot air sintering, hot air sintering, and steam injection sintering are carried out simultaneously on the sintering machine, thereby improving the quality indicators of sintered minerals.

[0036] 2: The system provided by the utility model utilizes the waste heat of the material surface after ignition. After superimposed heat exchange, high-parameter steam can be obtained, and the form and efficiency of the waste heat utilization of the ring-cooled exhaust gas can be improved. Moreover, by combining the waste heat utilization of the exhaust gas and the sintering hood into one, it can also save equipment investment and reduce site space occupancy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of the sintering system of the utility model.

[0038] Figure 2 This is a diagram showing the local structure of the sintering system described in the utility model.

[0039] Reference numerals: 1: main body hood; 101: first partition wall; 102: second partition wall; 2: oxygen supplement front chamber; 201: front section air inlet; 202: front zone oxygen nozzle; 203: steam superheat heat exchanger; 204: surface radiation heater; 205: front zone temperature sensor; 3: oxygen supplement middle chamber; 301: middle section air inlet; 302: middle zone oxygen nozzle; 303: evaporative heat exchanger; 304: middle zone temperature sensor; 4: Rear steam chamber; 401: Rear air inlet; 402: Rear water mist nozzle; 403: Industrial water heat exchanger; 404: Rear temperature sensor; 405: Steam concentration sensor; 5: Steam power generation device; 6: Plant oxygen network; 7: Steam drum; 8: Plant desalted water network; 9: Cooling air hood; 901: Waste gas recycling pipeline; 902: Circulating air duct; 903: Diverter valve; 10: Other hot water utilization networks in the plant. DETAILED DESCRIPTION

[0040] The technical solution of the utility model is illustrated below, and the scope of protection requested for the utility model includes but is not limited to the following embodiments.

[0041] A sintering system for recycling sintering ring-cooling waste gas, the sintering system comprises a sintering machine and a ring cooler connected in series, a main air hood 1 is provided above the sintering machine, a cooling air hood 9 is provided above the ring cooler, and the medium-temperature waste gas outlet of the cooling air hood 9 is respectively connected to the front air inlet 201, the middle air inlet 301 and the rear air inlet 401 of the main air hood 1 through three independent waste gas recycling pipes 901.

[0042] Preferably, the low-temperature exhaust gas outlet of the cooling air hood 9 is connected to the medium-temperature section air inlet of the ring cooler through the circulating air duct 902.

[0043] Preferably, the air inlet ends of the three independent exhaust gas recycling pipes 901 are connected to the medium-temperature exhaust gas outlet of the cooling air hood 9 through the diverter valve 903.

[0044] Preferably, a first partition wall 101 and a second partition wall 102 are provided in the main air hood 1, and the main air hood 1 is divided into an oxygen supplement front chamber 2, an oxygen supplement middle chamber 3 and a steam supplement rear chamber 4 along the running direction of the material by the first partition wall 101 and the second partition wall 102. The front section air inlet 201 is provided on the oxygen supplement front chamber 2, and a front section oxygen nozzle 202 is also provided above the interior of the oxygen supplement front chamber 2. The middle section air inlet 301 is provided on the oxygen supplement middle chamber 3, and a middle section oxygen nozzle 302 is also provided above the interior of the oxygen supplement middle chamber 3. The rear section air inlet 401 is provided on the steam supplement rear chamber 4, and a rear section water mist nozzle 402 is also provided above the interior of the steam supplement rear chamber 4.

[0045] Preferably, the oxygen supply front chamber 2 is located above the 1 / 25 material surface and the 5 / 25 material surface behind the ignition furnace of the sintering machine. The oxygen supply middle chamber 3 is located above the 6 / 25 material surface and the 15 / 25 material surface behind the ignition furnace of the sintering machine. The steam supply rear chamber 4 is located above the 16 / 25 material surface and the 23 / 25 material surface behind the ignition furnace of the sintering machine.

[0046] Preferably, a steam superheat heat exchanger 203 and a material surface radiation heater 204 are also provided in the oxygen supplementation front chamber 2. The steam superheat heat exchanger 203 is located below the front zone oxygen nozzle 202, and the material surface radiation heater 204 is located below the steam superheat heat exchanger 203. One end of the steam superheat heat exchanger 203 is connected to the steam drum 7 arranged outside the main body wind hood 1 through a pipeline, and the other end is connected to the inlet of the material surface radiation heater 204, and the outlet of the material surface radiation heater 204 is connected to the steam inlet of the steam power generation device 5 arranged outside the main body wind hood 1 through a pipeline.

[0047] Preferably, an evaporative heat exchanger 303 is further provided in the oxygen supplementation chamber 3, and the evaporative heat exchanger 303 is located below the middle oxygen nozzle 302. Both ends of the evaporative heat exchanger 303 are connected to the steam drum 7 provided outside the main air hood 1 through pipelines.

[0048] Preferably, an industrial water heat exchanger 403 is further provided in the supplementary steam rear chamber 4, and the industrial water heat exchanger 403 is located below the rear area water mist nozzle 402. The inlet end of the industrial water heat exchanger 403 is connected to the demineralized water pipe network 8 in the plant area through a pipeline, and the outlet end thereof is connected to the steam drum 7 arranged outside the main body wind hood 1 through a pipeline or is connected to other hot water utilization pipe networks 10 in the plant area through a pipeline.

[0049] Preferably, the air inlet ends of the front zone oxygen nozzle 202 and the middle zone oxygen nozzle 302 are independently connected to the plant area oxygen network 6 through pipelines.

[0050] Preferably, a front zone temperature sensor 205 is further provided below the material surface radiation heater 204 .

[0051] Preferably, a middle zone temperature sensor 304 is further provided below the evaporative heat exchanger 303 .

[0052] Preferably, a rear zone temperature sensor 404 and a steam concentration sensor 405 are further provided below the industrial water heat exchanger 403 .

[0053] Example 1

[0054] like Figure 1-2 As shown, a sintering system for recycling sintering ring-cooling waste gas, the sintering system includes a sintering machine and a ring cooler connected in series, a main air hood 1 is provided above the sintering machine, a cooling air hood 9 is provided above the ring cooler, and the medium-temperature waste gas outlet of the cooling air hood 9 is respectively connected to the front air inlet 201, the middle air inlet 301 and the rear air inlet 401 of the main air hood 1 through three independent waste gas recycling pipes 901.

[0055] Example 2

[0056] Example 1 is repeated, except that the low-temperature exhaust gas outlet of the cooling air hood 9 is connected to the medium-temperature section air inlet of the ring cooler through the circulating air duct 902.

[0057] Example 3

[0058] Example 2 is repeated, except that the air inlet ends of the three independent exhaust gas recycling pipes 901 are connected to the medium-temperature exhaust gas outlet of the cooling air hood 9 through the diverter valve 903.

[0059] Example 4

[0060] Example 3 is repeated, except that a first partition wall 101 and a second partition wall 102 are provided in the main air hood 1, and the main air hood 1 is divided into an oxygen supplement front chamber 2, an oxygen supplement middle chamber 3 and a steam supplement rear chamber 4 along the running direction of the material by the first partition wall 101 and the second partition wall 102. The front section air inlet 201 is provided on the oxygen supplement front chamber 2, and a front section oxygen nozzle 202 is also provided above the interior of the oxygen supplement front chamber 2. The middle section air inlet 301 is provided on the oxygen supplement middle chamber 3, and a middle section oxygen nozzle 302 is also provided above the interior of the oxygen supplement middle chamber 3. The rear section air inlet 401 is provided on the steam supplement rear chamber 4, and a rear section water mist nozzle 402 is also provided above the interior of the steam supplement rear chamber 4.

[0061] Example 5

[0062] Example 4 is repeated, except that the oxygen supply front chamber 2 is located above the 1 / 25 section material surface and the 5 / 25 section material surface behind the sintering machine ignition furnace. The oxygen supply middle chamber 3 is located above the 6 / 25 section material surface and the 15 / 25 section material surface behind the sintering machine ignition furnace. The steam supply rear chamber 4 is located above the 16 / 25 section material surface and the 23 / 25 section material surface behind the sintering machine ignition furnace.

[0063] Example 6

[0064] Example 5 is repeated, except that a steam superheat heat exchanger 203 and a material surface radiation heater 204 are also provided in the oxygen supplementation front chamber 2. The steam superheat heat exchanger 203 is located below the front zone oxygen nozzle 202, and the material surface radiation heater 204 is located below the steam superheat heat exchanger 203. One end of the steam superheat heat exchanger 203 is connected to the steam drum 7 provided outside the main body wind hood 1 through a pipeline, and the other end is connected to the inlet of the material surface radiation heater 204, and the outlet of the material surface radiation heater 204 is connected to the steam inlet of the steam power generation device 5 provided outside the main body wind hood 1 through a pipeline.

[0065] Example 7

[0066] Example 6 is repeated, except that an evaporative heat exchanger 303 is further provided in the oxygen supplementation chamber 3, and the evaporative heat exchanger 303 is located below the middle oxygen nozzle 302. Both ends of the evaporative heat exchanger 303 are connected to the steam drum 7 provided outside the main air hood 1 through pipelines.

[0067] Example 8

[0068] Example 7 is repeated, except that an industrial water heat exchanger 403 is further provided in the supplementary steam rear chamber 4, and the industrial water heat exchanger 403 is located below the rear area water mist nozzle 402. The inlet end of the industrial water heat exchanger 403 is connected to the desalted water pipe network 8 in the plant area through a pipeline, and the outlet end thereof is connected to the steam drum 7 provided outside the main body wind hood 1 through a pipeline or is connected to other hot water utilization pipe networks 10 in the plant area through a pipeline.

[0069] Example 9

[0070] Example 8 is repeated, except that the air inlet ends of the front zone oxygen nozzle 202 and the middle zone oxygen nozzle 302 are independently connected to the plant area oxygen network 6 through pipelines.

[0071] Example 10

[0072] Example 9 is repeated, except that a front zone temperature sensor 205 is further provided below the material surface radiation heater 204.

[0073] Embodiment 11

[0074] Example 10 is repeated, except that a middle zone temperature sensor 304 is further provided below the evaporative heat exchanger 303 .

[0075] Example 12

[0076] Example 11 is repeated, except that a rear zone temperature sensor 404 and a steam concentration sensor 405 are further provided below the industrial water heat exchanger 403 .

Claims

1. A sintering system for recycling sintering ring cooling waste gas, characterized in that: The sintering system comprises a sintering machine and an annular cooler which are connected in series in sequence. A main air hood (1) is provided above the sintering machine, and a cooling air hood (9) is provided above the annular cooler. The medium-temperature waste gas outlet of the cooling air hood (9) is respectively connected to a front air inlet (201), a middle air inlet (301) and a rear air inlet (401) of the main air hood (1) through three independent waste gas recycling pipelines (901).

2. The sintering system according to claim 1, characterized in that: The low-temperature exhaust gas outlet of the cooling air hood (9) is connected to the medium-temperature section air inlet of the ring cooler through the circulating air duct (902).

3. The sintering system according to claim 1 or 2, characterized in that: The air inlet ends of the three independent exhaust gas recycling pipelines (901) are connected to the medium-temperature exhaust gas outlet of the cooling air hood (9) through the diverter valve (903).

4. The sintering system according to claim 1 or 2, characterized in that: A first partition wall (101) and a second partition wall (102) are arranged in the main air hood (1), and the main air hood (1) is divided into an oxygen supply front chamber (2), an oxygen supply middle chamber (3) and a steam supply rear chamber (4) along the running direction of the material by the first partition wall (101) and the second partition wall (102); a front section air inlet (201) is arranged on the oxygen supply front chamber (2), and a front section oxygen nozzle (202) is also arranged above the interior of the oxygen supply front chamber (2); a middle section air inlet (301) is arranged on the oxygen supply middle chamber (3), and a middle section oxygen nozzle (302) is also arranged above the interior of the oxygen supply middle chamber (3); a rear section air inlet (401) is arranged on the steam supply rear chamber (4), and a rear section water mist nozzle (402) is also arranged above the interior of the steam supply rear chamber (4).

5. The sintering system according to claim 3, characterized in that: A first partition wall (101) and a second partition wall (102) are arranged in the main air hood (1), and the main air hood (1) is divided into an oxygen supply front chamber (2), an oxygen supply middle chamber (3) and a steam supply rear chamber (4) along the running direction of the material by the first partition wall (101) and the second partition wall (102); a front section air inlet (201) is arranged on the oxygen supply front chamber (2), and a front section oxygen nozzle (202) is also arranged above the interior of the oxygen supply front chamber (2); a middle section air inlet (301) is arranged on the oxygen supply middle chamber (3), and a middle section oxygen nozzle (302) is also arranged above the interior of the oxygen supply middle chamber (3); a rear section air inlet (401) is arranged on the steam supply rear chamber (4), and a rear section water mist nozzle (402) is also arranged above the interior of the steam supply rear chamber (4).

6. The sintering system according to claim 4, characterized in that: The oxygen supply front chamber (2) is located above the 1 / 25 material surface and the 5 / 25 material surface behind the ignition furnace of the sintering machine; the oxygen supply middle chamber (3) is located above the 6 / 25 material surface and the 15 / 25 material surface behind the ignition furnace of the sintering machine; and the steam supply rear chamber (4) is located above the 16 / 25 material surface and the 23 / 25 material surface behind the ignition furnace of the sintering machine.

7. The sintering system according to claim 5, characterized in that: The oxygen supply front chamber (2) is located above the 1 / 25 material surface and the 5 / 25 material surface behind the ignition furnace of the sintering machine; the oxygen supply middle chamber (3) is located above the 6 / 25 material surface and the 15 / 25 material surface behind the ignition furnace of the sintering machine; and the steam supply rear chamber (4) is located above the 16 / 25 material surface and the 23 / 25 material surface behind the ignition furnace of the sintering machine.

8. The sintering system according to claim 4, characterized in that: A steam superheat heat exchanger (203) and a material surface radiation heater (204) are also provided in the oxygen replenishment front chamber (2); the steam superheat heat exchanger (203) is located below the front zone oxygen nozzle (202), and the material surface radiation heater (204) is located below the steam superheat heat exchanger (203); one end of the steam superheat heat exchanger (203) is connected to a steam drum (7) provided outside the main body wind hood (1) through a pipeline, and the other end is connected to an inlet of the material surface radiation heater (204); and the outlet of the material surface radiation heater (204) is connected to a steam inlet of a steam power generation device (5) provided outside the main body wind hood (1) through a pipeline.

9. The sintering system according to any one of claims 5 to 7, characterized in that: A steam superheat heat exchanger (203) and a material surface radiation heater (204) are also provided in the oxygen replenishment front chamber (2); the steam superheat heat exchanger (203) is located below the front zone oxygen nozzle (202), and the material surface radiation heater (204) is located below the steam superheat heat exchanger (203); one end of the steam superheat heat exchanger (203) is connected to a steam drum (7) provided outside the main body wind hood (1) through a pipeline, and the other end is connected to an inlet of the material surface radiation heater (204); and the outlet of the material surface radiation heater (204) is connected to a steam inlet of a steam power generation device (5) provided outside the main body wind hood (1) through a pipeline.

10. The sintering system according to claim 8, characterized in that: An evaporative heat exchanger (303) is also provided in the oxygen replenishing middle chamber (3). The evaporative heat exchanger (303) is located below the middle oxygen nozzle (302). Both ends of the evaporative heat exchanger (303) are connected to a steam drum (7) provided outside the main air hood (1) through pipelines.

11. The sintering system according to claim 9, characterized in that: An evaporative heat exchanger (303) is also provided in the oxygen replenishing middle chamber (3). The evaporative heat exchanger (303) is located below the middle oxygen nozzle (302). Both ends of the evaporative heat exchanger (303) are connected to a steam drum (7) provided outside the main air hood (1) through pipelines.

12. The sintering system according to claim 10 or 11, characterized in that: An industrial water heat exchanger (403) is also provided in the steam supplement rear chamber (4), and the industrial water heat exchanger (403) is located below the rear area water mist nozzle (402); the inlet end of the industrial water heat exchanger (403) is connected to the desalted water pipe network (8) in the plant area through a pipeline, and the outlet end of the industrial water heat exchanger (403) is connected to the steam drum (7) provided outside the main body wind hood (1) through a pipeline.

13. The sintering system according to claim 12, characterized in that: The air inlet ends of the front zone oxygen nozzle (202) and the middle zone oxygen nozzle (302) are independently connected to the plant area oxygen pipe network (6) through pipelines.

14. The sintering system according to claim 12, characterized in that: A front zone temperature sensor (205) is further provided below the material surface radiation heater (204); and / or A middle zone temperature sensor (304) is further provided below the evaporative heat exchanger (303); and / or A rear zone temperature sensor (404) and a steam concentration sensor (405) are also provided below the industrial water heat exchanger (403).

15. The sintering system according to claim 13, characterized in that: A front zone temperature sensor (205) is further provided below the material surface radiation heater (204); and / or A middle zone temperature sensor (304) is further provided below the evaporative heat exchanger (303); and / or A rear zone temperature sensor (404) and a steam concentration sensor (405) are also provided below the industrial water heat exchanger (403).

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