Method for reducing FeO content of sintered ore and improving metallurgical performance of sintered ore

Abstract

The invention discloses a method for reducing the FeO content of sintered ore and improving the metallurgical performance of the sintered ore, and belongs to the technical field of ferrous metallurgy. According to the method, fuel is divided into fuel I and fuel II, the fuel I and sintering raw materials are mixed and granulated, obtained sintering materials are distributed on a sintering machine, and then the fuel II is distributed on the surface of the sintering materials; after material distribution is completed, ignition (adopting a two-time ignition mode), heat preservation, sintering and cooling are sequentially carried out, and sintered ore is obtained; according to the method, the technical means of combining fuel separate adding with two-time ignition is adopted, more heat can be supplied to the upper layer of the sintered material, the high-temperature holding time of the upper-layer sintered ore is prolonged, the cooling speed of the upper-layer sintered ore is reduced, meanwhile, the problem of excessive heat of the lower layer is solved, heat distribution in the height direction of the sintered material layer is more uniform, and the sintering efficiency is improved. According to the method, the burn-up of the sintering solid can be reduced, the FeO content of the sintered ore can be reduced, and the sintered ore with excellent metallurgical performance can be obtained.

Description

Technical Field

[0001] The present invention relates to a method for producing sintered ore, in particular to a method for reducing the FeO content of the sintered ore and improving the metallurgical properties of the sintered ore, belonging to the technical field of steel metallurgy. Background Art

[0002] Sintered ore, a core raw material for blast furnace ironmaking, accounts for up to 70% of the blast furnace charge. Its chemical composition and metallurgical properties directly impact the stability, energy efficiency, and carbon intensity of the blast furnace. FeO content is a key indicator of sintered ore quality. Currently, many steel mills use high fuel ratios during sintering to improve the low-temperature reduction pulverization index (LTRI) of sintered ore. This increases FeO content, thereby reducing the hematite content in the sintered ore and minimizing the occurrence of hematite reduction expansion. However, increased FeO content in sintered ore reduces its reducibility, increasing the blast furnace fuel ratio and thus maintaining high fuel ratios and carbon emissions for the overall ironmaking process. Research has shown that a 1% reduction in sintered ore FeO can reduce the blast furnace fuel ratio by 1.5%-2% and increase output by 1.5%-2%. Maintaining the sintered ore's low-temperature reduction pulverization index while reducing sintered ore FeO and further improving its reducibility could significantly reduce fuel ratios and carbon emissions for both sintering and the blast furnace.

[0003] A Chinese patent (CN119120892B) discloses a method for producing ultra-low FeO sintered ore. The method involves dividing the fuel into two parts, fuel I and fuel II. Fuel I is mixed and granulated with the sintering raw materials to obtain sintered ore. The sintered ore is then distributed to the sintering machine, and fuel II is then distributed to the sintered ore surface. Ignition, insulation, sintering, and cooling are performed. During the sintering process, an oxygen-rich gas medium is sprayed onto the sintered ore surface. During the cooling process, the sintered ore is first cooled by exhaust air on the sintering machine and then discharged to a ring cooler for cooling. This method reduces the sintering fuel ratio to increase the oxygen potential of the sintering material layer, thereby improving the FeO oxidation efficiency of the sintered ore. This method can produce sintered ore with an ultra-low FeO content (<6.5%). This method can significantly reduce the solid fuel consumption and FeO content of the sintered ore, but the low-temperature reduction pulverization index (RDI) of the sintered ore is significantly reduced. +3.15 Will decrease.

[0004] Prior art reports have reported the use of a secondary ignition method during the sintering process, primarily to increase the width of the combustion zone in the sintering layer and improve the yield of the upper layer. For example, Japanese Patent (JP7464844B2) discloses that the use of a secondary ignition method during flame heating can increase the width of the combustion zone in the sintering layer, thereby improving the yield of the upper layer. However, there are currently no reports on the use of a "fuel addition" coupled with "secondary ignition" technique to reduce the FeO content in the upper layer of sintered ore and promote the formation and crystallization of calcium ferrite. Summary of the Invention

[0005] In order to solve the technical problems existing in the prior art, the purpose of the present invention is to provide a method for reducing the FeO content of sintered ore and improving the metallurgical properties of sintered ore. The key to this method is to adopt a new technical means of "fuel addition" combined with "double ignition", which can increase the high temperature holding time of the sintering combustion zone of the sintering material, which is beneficial to the formation and crystallization of calcium ferrite. At the same time, the secondary ignition has an insulation effect on the upper layer of sintered ore, reduces the cooling rate of the upper layer of sintered ore, reduces the FeO content in the upper layer of sintered ore, and can reduce the combustion efficiency of the entire sintered ore mixture to a certain extent. The material ratio is improved, thereby further reducing the FeO content of the overall sintered ore. Under this method, the maximum temperature of the sintering material layer is reduced, the high temperature holding time is prolonged, the formation of skeletal hematite is reduced and the formation of composite calcium ferrite is promoted. It not only achieves the reduction of sintering solid fuel consumption and the FeO content of the sintered ore, but also improves the low-temperature reduction pulverization index and reducibility of the sintered ore, maintains high drum strength and finished product rate, and further reduces the coke ratio of the blast furnace. It provides a new method for carbon reduction and emission reduction in the ironmaking and sintering processes of the steel industry, which can produce huge economic and environmental benefits.

[0006] In order to achieve the above technical objectives, the present invention provides a method for reducing the FeO content of sintered ore and improving the metallurgical properties of the sintered ore, the method comprising the following steps:

[0007] 1) The fuel is divided into two parts, fuel I and fuel II. The fuel I is mixed with the sintering raw material and granulated to obtain the sintering material; the fuel The mass percentage composition of the fuel II is 94% to 97%: 3% to 6%;

[0008] 2) Placing the sintering material onto the sintering machine, and then placing the fuel II onto the sintering material surface;

[0009] 3) After the material is laid, ignition, heat preservation, sintering and cooling are carried out in sequence to obtain sintered ore;

[0010] Among them, the ignition adopts a two-time ignition method, the temperature of the first ignition is 1000±50℃, the time is 50~70s, and the second ignition is performed after an interval of 30~60s. The temperature of the second ignition is 800±50℃, and the time is 50~70s.

[0011] After a lot of experimental research, it was found that the distribution pattern of FeO content in sintered ore along the height direction of the sintered material layer is as follows: Figure 1As shown in the figure, the FeO content in the top layer of sintered ore is the highest, reaching 10.74%. The FeO content in the middle layers (layers 2-5) is the lowest, and the FeO content in the lower layers (layers 7-8) is on the rise. To address this phenomenon in sintered ore, the technical solution of the present invention mainly adopts the new technology of "fuel addition" combined with "double ignition", which not only reduces the FeO content in the sintered ore, but also improves the metallurgical properties of the sintered ore.

[0012] On the one hand, thick layer sintering can make good use of the heat storage principle, thereby reducing sintering solid fuel consumption, but the uneven heat distribution inside the material layer increases, the upper material layer has a serious lack of heat, and the lower material layer has an excess of heat. By adopting the "fuel addition" technology, part of the fuel can be distributed to the sintering material surface, making the heat distribution inside the material layer more uniform, the fuel ratio of the middle and lower layer sintered ore decreases, the reducing atmosphere is weakened during the sintering process, and the overall FeO content of the sintered ore will decrease. However, the surface layer of the sintered material layer will cause the FeO content in the sintered ore to further increase due to the increase in the fuel ratio. In order to overcome this technical problem, the present invention adopts a two-time ignition technical means. The secondary ignition can increase the high temperature maintenance time of the combustion zone during the sintering process, which is beneficial to the formation and crystallization of calcium ferrite. At the same time, the secondary ignition has the effect of keeping the upper layer sintered ore warm, reducing the cooling rate of the upper layer sintered ore, thereby reducing the FeO content of the upper layer sintered ore. It should be noted that setting a time interval of 30 to 60 seconds between the two ignitions can effectively prevent excessive heat concentration in the upper layer due to prolonged ignition, leading to overburning and deteriorating the permeability and sintering performance of the sintering bed. The temperature of the first ignition is around 1000°C. After the first ignition, the sintering combustion zone has been formed, and only a small amount of unburned carbon residue remains on the surface of the sintering bed. The temperature of the second ignition needs to be controlled at around 800°C to prolong the high temperature maintenance time of the upper bed. If the temperature of the second ignition is too high, it will cause excessive heat on the surface and over-melting of the surface sintered ore.

[0013] On the other hand, the low-temperature reduction pulverization index of sintered ore is closely related to the ore structure, for example, the form and amount of hematite that causes reduction expansion. Existing reports suggest that low-temperature reduction pulverization of sintered ore is primarily due to the reduction expansion of skeletal hematite. Skeletal hematite forms parallel to the sinter surface and structurally resembles an inclusion. The differential reduction rate between hematite and its internal crystalline inclusions is the primary cause of the expansion. Skeletal hematite is formed by oxidation of liquid magnetite when the temperature drops to within the hematite crystallization temperature range. Therefore, reducing the formation of liquid magnetite can reduce the formation of skeletal hematite. The combined "fuel splitting" and "double ignition" techniques lower the maximum temperature of the sinter bed and weaken the reducing atmosphere, thereby reducing the precursors for skeletal hematite formation. This, despite a slight increase in the remaining hematite content in the sinter, has a minimal impact on the low-temperature reduction pulverization of the sintered ore. Furthermore, the low-temperature reduction and pulverization of sintered ore is closely related to the content and morphology of the binder phase, which resists expansion stress and crack propagation. The binder phases in sintered ore are primarily complex calcium ferrite and silicate. Complex calcium ferrite has the highest strength, while silicate has lower strength. Therefore, increasing the content of complex calcium ferrite can improve the sinter's resistance to hematite reduction expansion stress and inhibit crack propagation. Common calcium ferrite structures include acicular calcium ferrite, columnar calcium ferrite, and dissolved calcium ferrite. Acicular calcium ferrite has the strongest resistance to reduction expansion stress and crack propagation, and its formation temperature is around 1275°C. Using a "fuel splitting" combined with a "double ignition" technique can increase the high-temperature hold time in the combustion zone and promote the formation of acicular calcium ferrite. It should also be noted that hematite and calcium ferrite are more easily reduced than magnetite and fayalite. Reducing the FeO content in the sintered ore, increasing the amount of liquid calcium ferrite, and increasing the amount of acicular calcium ferrite all contribute to improving the reducibility of the sintered ore.

[0014] Fuel in the fuel of the present invention The mass of fuel accounts for 94%~97%, The mass proportion of fuel is 3% to 6%. After adopting the "double ignition" technology, the proportion of fuel added to the surface of the sintering material layer should not be too high, as it will cause excess heat in the upper part. If the proportion is too low, the heat distribution will not be uniform. Therefore, it is best to control the fuel distribution ratio to 3-6%.

[0015] The "double ignition" technique employed in this invention, with a time interval between the two ignitions, is designed to prevent prolonged ignition, which can lead to excessive melting of the surface sinter due to overheating. This can lead to a brittle, glassy structure and reduced strength in the finished product. Similarly, if the ignition time is too short, ignition will not be completed, while if it is too long, the sinter layer temperature distribution may be uneven, affecting the uniformity and metallurgical properties (such as reducibility and cold strength) of the sintered ore.

[0016] As a preferred embodiment, the fuel particle size distribution is as follows: the mass proportion of particles <3 mm is greater than 85%, and the mass proportion of particles <1 mm is less than 20%. If the fuel particle size is too large, coarse particles will tend to segregate significantly during the distribution process, resulting in their concentration in the lower portion of the material bed. This uneven distribution results in a relatively insufficient fuel ratio in the upper portion of the sintering material bed, making it difficult to form a sufficient and uniform liquid phase, which in turn weakens the drum strength of the sinter and degrades its particle size composition. Simultaneously, the lower material bed, due to fuel enrichment, becomes excessive, leading to locally high temperatures. This high temperature inhibits the formation of composite calcium ferrite (SFCA) and may cause the decomposition of existing SFCA into hematite or magnetite. Furthermore, hematite itself is unstable at high temperatures and will further decompose into magnetite, ultimately increasing the FeO content in the sinter. Conversely, if the fuel particle size is too fine, the combustion rate will be accelerated, shortening the duration of the high-temperature zone in the material bed, resulting in insufficient development of the sintering liquid phase. This also compromises the overall quality of the sinter, manifesting as a simultaneous decrease in drum strength and yield. Moreover, excessively fine fuel particles are easily carried away by the airflow, significantly deteriorating the permeability of the sintered material layer.

[0017] As a preferred solution, the mass of the fuel is less than 3.5% of the mass of the sintering material. Under the condition of thick material layer sintering, the proportion of sintering fuel should not be too high to prevent the FeO content from increasing, so as to improve the reducibility of the sintered ore. The mass of the fuel is further preferably 3.2~3.5% of the mass of the sintering material. The present invention adopts the technology of "fuel addition" combined with "double ignition" to reduce the required proportion of fuel in the sintering mixture by 5~10% relative to conventional sintering. However, if the fuel reduction ratio is too high, the sintering heat will be excessive, the maximum temperature will still be high, and the overall FeO content of sintering will be difficult to reduce. If the fuel reduction ratio is too low, it will lead to insufficient sintering heat supply, and the yield and liquid phase volume cannot be guaranteed.

[0018] As a preferred solution, the thickness of the sintering material on the sintering machine is 900-1000mm. A thick material layer can effectively utilize the sintering heat storage principle and significantly reduce the sintering fuel ratio. Under the condition of a thick material layer, the potential for reducing the fuel ratio is greater.

[0019] As a preferred solution, the iron grade of the sintered material is not less than 57%, the mass content of MgO is less than 1.8%, the mass content of SiO2 is 5.0-5.5%, the mass content of Al2O3 is 1.5-2.0%, and the binary basicity is 1.8-2.2. The optimization design of the chemical composition of the sintered material of the present invention is based on the following mechanism: the addition amount of MgO needs to be controlled within 1.8%, because excessive Mg 2+ It will replace Fe in the magnetite lattice 2+, occupying the octahedral interstitial positions, thereby reducing lattice defects, enhancing the stability of magnetite and leading to an increase in FeO content; at the same time, too low SiO2 content is not conducive to the formation of composite calcium ferrite. SiO2 easily reacts with Fe3O4 to form fayalite phase under low temperature conditions, and its excessive content will also promote the increase of FeO; the introduction of an appropriate amount of Al2O3 is conducive to the formation of calcium ferrite and the development of composite calcium ferrite, and can improve the fluidity of the sintering liquid phase, promote oxygen ion migration to optimize the oxidation process, but excessive Al2O3 will aggravate the low-temperature reduction and pulverization tendency of the sintered ore; in addition, maintaining the basicity above 1.8 can ensure that the proportion of calcium ferrite phase reaches 30%~40%, thereby ensuring the strength of the sintered ore, but too high basicity will reduce the iron grade and increase the amount of blast furnace slag, affecting the blast furnace smelting efficiency.

[0020] Compared with the existing technology, the technical solution of the present invention brings the following beneficial technical effects:

[0021] The present invention adopts a new technology of "fuel fractionation" combined with "double ignition" in the sinter preparation process, which not only reduces the solid fuel consumption of sintering and reduces the FeO content of the sintered ore, but also improves the low-temperature reduction pulverization index and reducibility of the sintered ore, maintains high drum strength and yield, and further reduces the coke ratio of the blast furnace. It provides a new method for reducing carbon emissions and emissions in the ironmaking and sintering processes of the steel industry, which can generate huge economic and environmental benefits. More specifically:

[0022] (1) It can make the heat distribution of the sintering material layer more uniform, reduce the total fuel ratio of the sintered ore, reduce the FeO content in the lower layer of the sintered ore, and at the same time reduce the cooling rate of the upper layer of the sintered ore, promote the oxidation of FeO in the upper layer of the sintered ore, thereby reducing the FeO content in the sintered ore as a whole.

[0023] (2) On the basis of reducing the total fuel ratio, the maximum sintering temperature is reduced and the reducing atmosphere of the material layer is weakened, which reduces the skeletal hematite generated by the oxidation of magnetite under high temperature conditions. At the same time, it can increase the high temperature holding time of the sintering material, help the formation of sintering liquid phase calcium ferrite, and enhance the ability of the sintered ore to resist low-temperature reduction pulverization.

[0024] (3) It can increase the production of hematite and calcium ferrite with good reducibility, which is beneficial to the improvement of reducibility, and realize the reduction of fuel ratio and energy conservation and emission reduction of blast furnace.

[0025] (4) By controlling the temperature and time interval of the two ignitions, the metallurgical properties of the sintered ore can be effectively improved. On the one hand, the time interval between the two ignitions is set to 30~60s, which can effectively prevent the over-concentration of heat in the upper layer due to continuous long-term ignition, resulting in over-burning, which deteriorates the permeability and sintering index of the sintering material layer. On the other hand, the temperature of the first ignition is about 1000℃. After the first ignition, the sintering combustion zone has been formed, and there is only a small amount of unburned carbon residue on the surface of the sintering material layer. The temperature of the second ignition needs to be controlled at about 800℃, which can extend the high temperature maintenance time of the upper material layer. If the temperature of the second ignition is too high, it will cause excessive heat on the surface and cause the surface sintered ore to over-melt.

[0026] (5) Based on the fact that "fuel fractionation" will increase the FeO content in the sintered ore of the surface layer of the sintered material layer due to the increase in the fuel ratio, and at the same time increase the carbon residue in the upper sintered material layer, the present invention adopts the "double ignition" technical means to solve the technical problems brought about by "fuel fractionation". The "double ignition" process compensates for the uneven heat distribution in the upper layer, making the heat distribution of the material layer more uniform, and at the same time broadens the high temperature holding time, so that the calcium ferrite content in the upper material layer increases, the crystallization is more complete, and the strength is higher; the "double ignition" process can greatly slow down the cooling rate, ensure the oxidation of FeO in the sintered ore, and reduce the FeO content of the surface and upper sintered ore. At the same time, the secondary ignition can ignite the residual carbon in the upper material layer, and use it to provide more heat, thereby reducing heat loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the distribution pattern of FeO content in the sintered ore along the height direction of the sintered material layer in Example 1. DETAILED DESCRIPTION

[0028] To facilitate understanding of the present invention, the present invention will be described in more comprehensive and detailed form below in conjunction with preferred embodiments. However, the scope of protection of the claims of the present invention is not limited to the following specific embodiments.

[0029] Unless otherwise defined, all technical terms used hereinafter have the same meanings as those commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the claims of the present invention.

[0030] Example 1

[0031] According to the sintering mixture composition TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, binary basicity CaO / SiO2 = 2.0, the ingredients are prepared, the coke powder ratio is 3.42%, of which the coke powder particle size <3mm accounts for 87%, and <1mm accounts for 15%. 94% of the total coke powder is mixed with the sintering mixture for granulation, and the mixture is distributed on the sintering machine with a distribution height of 950mm. Then the remaining (total 6%) coke powder is distributed on the surface of the sintering mixture. Ignite at 1000±50℃ for 1min, then after an interval of 40s, ignite again at 800±50℃ for 1min, and then sinter under negative pressure of 12kPa. The sintering end point is when the sintering flue gas temperature reaches the highest point. After using the method described in this embodiment, the FeO distribution of the sintered ore is as follows Figure 1 The effects on sintering index, FeO content and metallurgical properties are shown in Table 1 and Table 2.

[0032] Example 2

[0033] The sintering mix was prepared according to its composition: TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, and a binary basicity of CaO / SiO2 = 2.0. The coke powder ratio was 3.38%, of which 87% were coke powder particles < 3 mm, and 15% were < 1 mm. 95% of the total coke powder was mixed with the sintering mix and pelletized. The mix was distributed to a sintering machine at a height of 980 mm, and the remaining coke powder (5% of the total amount) was then distributed on the surface of the sintering mix. Ignition was performed at 1000 ± 50°C for 1 minute, followed by a 40-second interval and a secondary ignition at 800 ± 50°C for 1 minute. Sintering was then carried out under a negative pressure of 12 kPa. Sintering was terminated when the sintering flue gas temperature reached its peak. The effects of the method described in this example on sintering performance, FeO content, and metallurgical properties are shown in Tables 1 and 2.

[0034] Example 3

[0035] The sintering mix was prepared according to its composition: TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, and a binary basicity of CaO / SiO2 = 2.0. The coke powder ratio was 3.32%, of which 87% were coke powder particles < 3 mm, and 15% were < 1 mm. 97% of the total coke powder was mixed with the sintering mix and pelletized. The mix was distributed to a sintering machine at a height of 1000 mm, and the remaining coke powder (3% of the total amount) was then distributed on the surface of the sintering mix. Ignition was performed at 1000 ± 50°C for 1 minute, followed by a 50-second interval and a secondary ignition at 800 ± 50°C for 1 minute. Sintering was then carried out under a negative pressure of 12 kPa. Sintering was terminated when the sintering flue gas temperature reached its peak. The effects of the method described in this example on sintering performance, FeO content, and metallurgical properties are shown in Tables 1 and 2.

[0036] Comparative Example 1 (Benchmark Sintering)

[0037] According to the sintering mixture composition TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, binary basicity CaO / SiO2 = 2.0, the materials are prepared, the coke powder ratio is 3.6%, the sintering material is mixed and granulated, and the mixture is distributed on the sintering machine with a distribution height of 950mm. It is ignited at 1000±50℃ for 1min, and then sintered under a negative pressure of 12kPa. The sintering end point is when the sintering flue gas temperature reaches the highest point. After using the method described in this embodiment, the FeO distribution of the sintered ore is as follows: Figure 1 The effects on sintering index, FeO content and metallurgical properties are shown in Table 1 and Table 2.

[0038] Comparative Example 2 (without secondary ignition)

[0039] According to the sintering mixture composition TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, binary basicity CaO / SiO2 = 2.0, the ingredients are prepared, the coke powder ratio is 3.42%, of which the coke powder particle size <3mm accounts for 87%, and <1mm accounts for 15%. 94% of the total coke powder is mixed with the sintering mixture for granulation, and the mixture is distributed on the sintering machine with a distribution height of 950mm. Then the remaining (total 6%) coke powder is distributed on the surface of the sintering mixture. Ignite for 1 minute under the condition of 1000±50℃, and then sinter under the condition of negative pressure of 12kPa. The sintering end point is when the sintering flue gas temperature reaches the highest point. After using the method described in this embodiment, the FeO distribution of the sintered ore is as follows Figure 1 The effects on sintering index, FeO content and metallurgical properties are shown in Table 1 and Table 2.

[0040] Comparative Example 3 (no fuel addition)

[0041] According to the sintering mixture composition TFe = 57.6%, MgO = 1.74%, SiO2 = 5.25%, Al2O3 = 1.86%, binary basicity CaO / SiO2 = 2.0, the ingredients are prepared, the coke powder ratio is 3.5%, of which the coke powder particle size <3mm accounts for 87%, and <1mm accounts for 15%. The coke powder is mixed with the sintering mixture and granulated, and the mixture is distributed on the sintering machine with a distribution height of 950mm. Ignite at 1000±50℃ for 1min, then after an interval of 40s, ignite again at 800±50℃ for 1min, and then sinter under negative pressure of 12kPa. The sintering end point is when the sintering flue gas temperature reaches the highest point. After using the method described in this embodiment, the FeO distribution of the sintered ore is as follows: Figure 1 The effects on sintering index, FeO content and metallurgical properties are shown in Table 1 and Table 2.

[0042]

[0043]

[0044] According to Example 1 and Comparative Examples 1 to 3, it can be seen that the technical means of "separate addition of fuel" and "double ignition" alone have little effect on reducing the FeO content in the sintered ore and improving the metallurgical properties of the sintered ore. However, the coupling technical means of "separate addition of fuel" combined with "double ignition" has a significant synergistic effect, which not only reduces the FeO content in the sintered ore, but also improves the low-temperature reduction pulverization index and reducibility of the sintered ore, and maintains high drum strength and yield.

Claims

1. A method for reducing the FeO content of sintered ore and improving the metallurgical properties of the sintered ore, characterized by: The following steps are involved: 1) The fuel is divided into two parts, fuel I and fuel II. The fuel I is mixed with the sintering raw material and granulated to obtain the sintering material; the fuel The mass percentage composition of the fuel II is 94% to 97%: 3% to 6%; 2) Placing the sintering material onto the sintering machine, and then placing the fuel II onto the sintering material surface; 3) After the material is laid, ignition, heat preservation, sintering and cooling are carried out in sequence to obtain sintered ore; Among them, the ignition adopts a two-time ignition method, the temperature of the first ignition is 1000±50℃, the time is 50~70s, and the second ignition is performed after an interval of 30~60s. The temperature of the second ignition is 800±50℃, and the time is 50~70s.

2. The method for reducing the FeO content of sintered ore and improving the metallurgical properties of sintered ore according to claim 1, characterized in that: The particle size distribution of the fuel is as follows: the mass proportion of particles with a size <3 mm is greater than 85%, and the mass proportion of particles with a size <1 mm is less than 20%.

3. The method for reducing the FeO content of sintered ore and improving the metallurgical properties of sintered ore according to claim 1 or 2, characterized in that: The mass of the fuel accounts for less than 3.5% of the mass of the sintering material.

4. The method for reducing the FeO content of sintered ore and improving the metallurgical properties of sintered ore according to claim 1, characterized in that: The thickness of the sintering material on the sintering machine is 900-1000 mm.

5. The method for reducing the FeO content of sintered ore and improving the metallurgical properties of sintered ore according to claim 1, characterized in that: The iron grade of the sintered material is not less than 57%, the mass content of MgO is <1.8%, the mass content of SiO2 is 5.0-5.5%, the mass content of Al2O3 is 1.5%-2.0%, and the binary basicity is 1.8-2.2.

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