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CN-121994026-A - Sintering machine energy-saving system and method based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion

CN121994026ACN 121994026 ACN121994026 ACN 121994026ACN-121994026-A

Abstract

The invention relates to the technical field of ferrous metallurgy sintering processes, in particular to a sintering machine energy-saving system and method based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion, comprising a low-temperature hot air recovery unit, an oxygen-enriched mixing unit, an emission detection unit and an intelligent regulation and control unit, the low-temperature hot air at the tail section of the circular cooler is introduced into a closed cover of a mineral material layer of the sintering machine by the suction force of a draught fan, and the uniform oxygen-enriched hot air passes through the sintered mineral material layer to burn and completely react with solid fuel-coke powder in the low-temperature hot air by improving the oxygen enrichment degree of the hot air in the closed cover and being driven by the negative pressure of an air box below the material surface. The invention has the advantages of high reaction speed, high theoretical combustion temperature, CO emission reduction while sintering the auxiliary sintering ore, energy saving and yield improvement.

Inventors

  • Chi Jianzhou
  • SHANG ZHIHONG

Assignees

  • 南京林普热能科技有限公司

Dates

Publication Date
20260508
Application Date
20260212

Claims (10)

  1. 1. The sintering machine energy-saving system based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion comprises a low-temperature hot air recovery unit, an oxygen-enriched mixing unit, an emission detection unit and an intelligent regulation and control unit, and is characterized in that the low-temperature hot air recovery unit comprises a low-temperature hot air pipeline system, the annular cooler tail low-temperature hot air is conveyed into a closed cover of a sintering machine material surface through the low-temperature hot air pipeline system, the low-temperature hot air pipeline system comprises a hot air pipeline, a hot air pipeline and a transition air guide pipe, one end of the hot air pipeline is connected with a wind collecting cover of the annular cooler tail section, the other end of the hot air pipeline is connected with a hot air pipeline at the position of the sintering machine material surface, and the hot air pipeline is sequentially connected with a plurality of transition air guide pipes into the closed cover; the oxygen-enriched mixing unit adopts graded oxygen supply, wherein the primary oxygen supply is used for supplying oxygen by uniformly spraying oxygen Kong Duiguan in the radial direction of an annular pipe on a hot air pipeline, the volume concentration control range of the primary oxygen supply is 22% -23%, the secondary oxygen supply is used for mixing oxygen with low-temperature hot air at the tail of an annular cooler by arranging a jet oxygen gun in a transition air guide pipe, and the volume concentration control range of the secondary oxygen supply is 24% -28%; the emission detection unit is used for monitoring the oxygen concentration by arranging an oxygen concentration analysis monitor in the low-temperature hot air pipeline system and the closed cover; And the intelligent regulation and control unit is used for dynamically regulating and controlling the air quantity, the temperature and the oxygen injection quantity of the low-temperature hot air at the tail section of the annular cooling and dynamically regulating the frequency of the induced draft fan.
  2. 2. The sintering machine energy-saving system based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion as set forth in claim 1, wherein the hot air pipeline is provided with an induced draft fan and a dust remover.
  3. 3. The sintering machine energy-saving system based on the annular cooler tail section hot air recycling coupling oxygen-enriched combustion, which is disclosed by claim 2, is characterized in that the air quantity of the induced draft fan is 5-10 ten thousand Nm3/h, the air pressure is more than or equal to 5000Pa, the dust content at the outlet of the dust remover is less than or equal to 50mg/Nm3, and the dust removal efficiency is more than or equal to 85%.
  4. 4. The energy-saving system of the sintering machine based on the annular cooler tail section hot air recycling coupling oxygen-enriched combustion, which is disclosed in claim 1, is characterized in that the oxygen spraying holes for primary oxygen supply are arranged on a hot air pipeline in front of an induced draft fan.
  5. 5. The energy-saving system of the sintering machine based on the annular cooler tail section hot air recycling coupling oxygen-enriched combustion, which is disclosed in claim 1, is characterized in that the transition air guide pipes are correspondingly connected with the sealing cover of the No. 6 air box after ignition of the machine head and the No.3 air box before the sintering end point.
  6. 6. The sintering machine energy-saving system based on annular cooler tail hot air recycling coupling oxygen-enriched combustion as set forth in claim 1, wherein the secondary oxygen supply in the plurality of transition air guide pipes adopts sequential gradient oxygen supply, and the oxygen volume concentration is supplied from the machine head to the machine tail in a mode of from high to low.
  7. 7. The energy-saving system of the sintering machine based on the annular cooler tail section hot air recycling coupling oxygen-enriched combustion is characterized in that the emission detection unit further comprises a residual oxygen concentration monitor and a CO concentration monitor which are arranged on a wind box vertical pipe corresponding to the sintering machine respectively and used for detecting residual oxygen concentration and CO concentration content in flue gas, and a NOx concentration monitor and a CO concentration monitor are arranged on a main pumping flue of the sintering machine and used for detecting the concentration content of NOx emission and the final CO emission of the flue gas respectively.
  8. 8. The sintering machine energy-saving system based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion according to claim 1, wherein a flowmeter and a hot air regulating valve are sequentially arranged on the low-temperature hot air pipeline system.
  9. 9. The energy-saving system of the sintering machine based on the annular cooler tail section hot air recycling coupling oxygen-enriched combustion is characterized in that the temperature of hot air in the low-temperature hot air pipeline system is generally 80-160 ℃.
  10. 10. The oxygen-enriched sintering method of the energy-saving system of the sintering machine based on the coupling of the annular cooler tail section hot air recycling and the oxygen-enriched combustion, which is disclosed in claim 1, is characterized by comprising the following steps: S1, collecting evacuated low-temperature hot air at the tail section of the circular cooler by a low-temperature hot air recovery unit, entering a circular cooler tail section air collecting cover, connecting a hot air pipeline by the air collecting cover, feeding the hot air pipeline into a hot air collecting pipe at the outer side of a closed cover of a trolley material surface of the sintering machine by the suction force of a draught fan, and respectively connecting a plurality of transition air guide pipes by the hot air collecting pipe to send the low-temperature hot air into the closed cover for hot air sintering; S2, conveying an oxygen medium through an oxygen source pipeline, grading oxygen supply through an oxygen-enriched mixing unit, wherein the primary oxygen supply is arranged on a hot air pipeline, the secondary oxygen supply is realized through inserting a jet flow oxygen gun on a transition air guide pipe, and oxygen-enriched hot air after graded oxygen mixing is conveyed into a trolley material surface sealing cover of the sintering machine; S3, controlling oxygen supply quantity of a jet flow oxygen gun for secondary oxygen supply through an intelligent regulation and control unit by using oxygen concentration detected in an oxygen concentration analysis monitor in the closed cover, so that gradient oxygen enrichment is carried out on the sintering production along the firing to sintering end point, and a hot air oxygen enrichment sintering process is formed; S4, oxygen-enriched sintering information is obtained in real time through an oxygen concentration analysis monitor, a CO concentration detector, a NOx concentration detector and a residual oxygen detector which are arranged by the emission detection unit, and an intelligent regulation and control unit is combined to dynamically control the sintering hot air oxygen-enriched sintering process.

Description

Sintering machine energy-saving system and method based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion Technical Field The invention relates to the technical field of ferrous metallurgy sintering processes, in particular to a sintering machine energy-saving system and method based on annular cooler tail section hot air recycling coupling oxygen-enriched combustion. Background Currently, the steel industry is still in a deep adjustment period, the surplus capacity and the green transformation pressure coexist, the market competition is more and more vigorous, and the cost reduction and the synergy become the basis for the survival of enterprises. The energy consumption of the sintering process is 12% of the total energy consumption of steel production, and the carbon emission is up to 15%. In the aspect of environmental emission, the sintering system is not only a large household for emission of nitrogen oxides and sulfides, but also the CO escape in the flue gas of the sintering machine system is the most serious emission source in all the working procedures of steel production. In addition, from the viewpoint of waste heat utilization, low-temperature hot air at the tail section of a circular cooler in the traditional sintering production process is directly discharged, the waste heat utilization rate is very low (< 30 percent), and the policy requirements are not met far under the background of the current full-flow energy efficiency of steel production. The CO content in the flue gas emitted by sintering machine systems varies due to a number of factors involved in their principle of formation. Research and analysis show that the combustion reaction factor is the most important link of influence. The conventional combustion process often has the defects that partial oxygen deficiency is caused, incomplete combustion is generated, incomplete combustion is also generated due to low flame temperature, and as a result, combustible substances become smoke dust to be discharged, a large amount of CO escapes, energy is wasted, and atmospheric pollution is caused. The investigation result shows that if only adopting the mode of recycling sintering flue gas (the cold and hot air is in anoxic working condition and oxygen content is 17-18%), and blowing steam or hydrogen gas and natural gas on the material surface to reduce emission from source, the CO emission concentration of sintering flue gas can generally be only less than about 6000mg/m3, while the catalytic oxidation treatment process can reach the standard, but the treatment process belongs to tail terminal treatment and has high investment and operation cost, and the treatment mode of burning CO and recovering waste heat to produce steam at the terminal can reach the standard, but the energy conversion efficiency is greatly reduced, and the heat energy as combustible CO is not released in the system but is discharged outside for secondary conversion, which is not preferable. Through technical research and development and engineering experiments, the application of the oxygen-enriched sintering (material surface oxygen enrichment) technology can show the advantages of pollution and carbon reduction, cost reduction and synergy, and the CO can be more effectively assisted and reduced by the cooperation of the waste heat utilization of the annular cooling waste gas, so that the emission concentration of the CO in the sintering flue gas reaches 2800mg/m < 3 > or less, and therefore, an energy-saving system and an energy-saving method for achieving oxygen-enriched sintering by efficiently utilizing the annular cooling waste gas are needed. Disclosure of Invention In order to overcome the defects of the prior art, the invention provides an energy-saving system and a method for a sintering machine based on coupling oxygen-enriched combustion of hot air recycling at the tail section of a circular cooler, which are characterized in that low-temperature hot air at the tail section of the circular cooler is introduced into a closed cover of a mineral material layer of the sintering machine through the suction force of a draught fan, and uniform oxygen-enriched hot air passes through the mineral material layer by improving the oxygen enrichment degree of the hot air in the closed cover and being driven by negative pressure of an air box below a material surface, and the uniform oxygen-enriched hot air is combusted and fully reacted with solid fuel-coke powder in the sintering material layer, so that the reaction speed is high, the theoretical combustion temperature is high, the emission of CO is reduced while the sintering of the sintering ore is assisted, and the energy is saved and the yield is improved. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: The sintering machine energy-saving system based on annular cooler tail section hot air recycling coupling oxygen-enrich