Homogeneous sintered ore production process based on super-thick material layer

Abstract

The invention relates to the technical field of sintering processes, in particular to a homogeneous sinter production process based on a super-thick material layer. The homogeneous sinter production process based on the super-thick material layer comprises the following steps: preparing a sintering mixture; uniformly mixing the mixture and pelletizing; distributing the mixture; igniting and sintering. According to the method, a full-active ash digestion strengthening granulation technology is adopted, the average particle size of the mixture is increased, the air permeability of the mixture is greatly improved, the drum strength and the yield of the sintered ore are improved while ultra-thick material layer production is achieved, the return ore rate and sintering solid fuel consumption are reduced, and the method has great application and popularization value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sintering process, in particular to a homogeneous sinter production process based on super-thick material layer. BACKGROUND

[0002] Super-thick material layer production is an important means to realize quality improvement and consumption reduction in sintering process. Thick material layer sintering production can better play the role of automatic heat accumulation in the sintering production process, and accumulate the heat required in the sintering process. In theory, the thicker the material layer, the higher the heat accumulation efficiency, and the longer the high-temperature maintenance time, which is beneficial to the formation of liquid phase, and further beneficial to the improvement of sinter drum strength, reduction of return fines rate and sinter solid fuel consumption. Thick material layer sintering technology is an advanced sintering technology developed based on calcium ferrite solidification theory and self-heat accumulation, which has been widely used in China in recent years. As of now, the material layer thickness of sintering machines in some steel enterprises such as TISCO Joint Special Steel, Ansteel, Shaanxi Steel, Xianggang and Ma Steel has exceeded 900 mm, and good production results have been achieved.

[0003] In the prior art, a sinter production method for achieving a sintering machine material thickness of 950mm-1000mm is disclosed in Chinese patent application No. 202210612296.7, which includes the following steps: configuring sintering mixture, mixing and balling the mixture, reducing the sintering system air leakage rate, laying the bottom material at the bottom of the sintering machine trolley, and installing the material loosening device below the material distribution platform, distributing the mixture on the sintering trolley through the material distribution device, and igniting and sintering the mixture on the surface of the trolley through the ignition device. The above sintering process can effectively increase the sintering material layer thickness to 950-1000mm, while helping to reduce fuel consumption and power consumption, improve sinter quality, and reduce sintering production cost, but the above process still has the problem of low sinter drum index.

[0004] To solve the above problems, the present application provides a homogeneous sinter production process based on super-thick material, which further improves the average particle size of the mixture and improves the permeability of the mixture by using full-activity ash digestion and strengthening granulation technology, and adjusts the adaptability of related equipment, aiming to further improve the drum strength of sinter, reduce the return rate and solid fuel consumption. SUMMARY

[0005] The present application aims to provide a homogeneous sinter production process based on super-thick material layer. To achieve the above purpose, the technical solution adopted by the present application is as follows:

[0006] The homogeneous sinter production process based on super-thick material layer according to the present application includes the following steps:

[0007] S1 preparation of sintering mixture:

[0008] The iron-containing raw material, flux, fuel and return ore are proportioned; wherein the flux is active lime, the CaO content of which is above 90%, and the activity is above 310 mL;

[0009] S2: mixing and balling of the mixture

[0010] The mixed material prepared in step S1 is delivered to a mixing and balling system for mixing and balling, so that the moisture content of the mixed material after mixing and balling is controlled to be 6.5%-8.3%, and the proportion of the particle size >3 mm in the mixed material after mixing and balling is above 70%;

[0011] S3: distribution of the mixture

[0012] The bottom material is laid on the bottom of the sintering machine trolley, and the shuttle distributor, mud roller and nine-roller distributor are combined for distribution.

[0013] S4: ignition sintering

[0014] The ignition device is used to ignite and sinter the surface layer of the trolley.

[0015] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the iron-containing raw material in the preparation of the sintering mixture in step S1 includes iron-containing powder and dust removal ash, and the mass ratio in the total mixture is 66%-80%.

[0016] The iron-containing powder includes imported powder, domestic powder and recycled resources. The imported powder mainly includes Brazilian ore (BRBF, high-silicon Ba coarse powder, Ka powder, etc.), Australian ore (SP10 powder, MacK powder, FMG mixed powder, super special powder, Silk Road powder, etc.), and other regional ore powder (India powder, South Africa powder, Russia powder, etc.). The domestic powder mainly includes 62 iron concentrate powder, siderite powder, brown iron powder, 50 medium powder, etc. The recycled resources mainly include magnetic separation powder and Feiqing iron powder.

[0017] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the mass ratio of the active lime as the flux in the preparation of the sintering mixture in step S1 in the total mixture is 3.5%-5%.

[0018] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the fuel in the preparation of the sintering mixture in step S1 is any one or both of anthracite and powder coke, and the mass ratio in the total mixture is 3.6%-4.7%.

[0019] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the mass ratio of the return ore in the sintering mixture in step S1 in the total mixture is 10.6%-15.5%.

[0020] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the mixing and balling time of the mixed material in step S2 is more than 7.64 min.

[0021] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the moisture content of the mixed material after mixing and balling in step S2 is controlled to be 7.7% to 8.0%.

[0022] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the particle size of the bottom material in the material distribution of the mixed material in step S3 is 10 to 16 mm, the laying thickness of the bottom material is 40 to 80 mm, and the thickness of the material layer after distribution is 920 to 1000 mm.

[0023] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the distribution system in the material distribution of the mixed material in step S3 is as follows: the shuttle distribution machine stroke is 5.5 to 6 m; the mixed material bin level is 1 / 3 to 1 / 2; the valve opening control is 30% to 60%; and the nine-roller rotation speed is 20 to 40 hz.

[0024] Preferably, in the production process of the homogeneous sinter based on the super-thick material layer, the ignition sintering in step S4 controls the ignition negative pressure to be -5.0 to -8.0 kPa.

[0025] The beneficial effects of the present application are as follows:

[0026] The present application provides a production process of homogeneous sinter based on a super-thick material layer. By using the full-activity ash digestion and strengthening granulation technology, the average particle size of the mixed material is improved, and the air permeability of the mixed material is greatly improved. At the same time, combined with the adaptability of the related process facilities, the super-thick material layer production is realized, the drum strength of the sinter is improved (in the research example, the highest reaches 83.25%), the yield is improved (in the research example, the highest reaches 84.7%), the return ore rate and the sinter solid fuel consumption are reduced (in the research example, the lowest reaches 21.61 kwh / t), and the application value is great. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The sintering machine trolley fence is modified. DETAILED DESCRIPTION

[0028] The technical solutions of the present application are described in detail below in combination with specific examples. The following examples are only used for explanation and illustration, and do not constitute a limitation on the technical solutions of the present application.

[0029] Example 1

[0030] The production process of the homogeneous sinter based on the super-thick material layer is as follows:

[0031] (1) Preparation of sintering mixture:

[0032] The sintering mix consists of iron-containing raw materials, flux, fuel, and return ore. The iron-containing raw materials include iron-containing ore fines and dust ash, accounting for 79.5% of the mix by weight. The flux is activated quicklime with a CaO content of 90.92% and an activity of 310 mL, accounting for 4.8% of the mix by weight. The fuel consists of coke powder and pulverized coal, accounting for 4.7% by weight. Return ore accounts for 11% by weight.

[0033] (2) Mixing and pelletizing of the mixture:

[0034] The prepared sintering mixture is conveyed to the mixing and pelletizing system for mixing and pelletizing. The mixing and pelletizing time is 7.66 minutes. The moisture content of the mixture after mixing and pelletizing is controlled to be 7.9%. The proportion of particle size > 3 mm in the mixture after mixing and pelletizing is 76.34%.

[0035] (3) Mixed fabric:

[0036] The base material is laid on the bottom of the sintering machine trolley and is distributed by a shuttle distributor and a nine-roller distributor. The particle size range of the base material is 10-16 mm, and the laying thickness of the base material is 40 mm. The thickness of the material layer after distribution is 1000 mm. The distribution system is as follows:

[0037] The shuttle feeder stroke is 5.5m; the material level of the mixed material silo is 1 / 3; the valve opening control is 30%; the nine-roller speed is 20hz.

[0038] (4) Ignition and sintering:

[0039] The surface mixture of the trolley is ignited and sintered by the ignition device, and the ignition negative pressure is controlled at -8.0kPa.

[0040] Example 2

[0041] The homogeneous sinter production process based on ultra-thick material layer is as follows:

[0042] (1) Preparation of sintering mixture:

[0043] The sintering mix consists of iron-containing raw materials, flux, fuel, and return ore. The iron-containing raw materials include iron-containing ore fines and dust ash, accounting for 79.9% of the mix by weight. The flux is activated quicklime with a CaO content of 90.92% and an activity of 310 mL, accounting for 4.0% of the mix by weight. The fuel consists of coke powder and pulverized coal, accounting for 4.1% by weight. Return ore accounts for 12% by weight.

[0044] (2) Mixing and pelletizing of the mixture:

[0045] The prepared sintering mixture is transported to a mixing and balling system for mixing and balling, the mixing and balling time is 8.15 min, the moisture content of the mixture after mixing and balling is controlled to be 7.7%, and the proportion of the particle size > 3 mm in the mixture after mixing and balling is 76.55%.

[0046] (3) Mixture distribution:

[0047] The bottom material is laid at the bottom of the sintering machine trolley, and a shuttle distributor and a nine-roller distributor are used for joint distribution. The particle size of the bottom material is 10-16 mm, and the laying thickness of the bottom material is 50 mm; the thickness of the distributed material layer is 950 mm; the distribution system is as follows:

[0048] The stroke of the shuttle distributor is 6 m; the mixture bin level is 1 / 2; the valve opening control is 60%; and the nine-roller speed is 40 hz.

[0049] (4) Ignition sintering:

[0050] The surface layer of the trolley is ignited and sintered by the ignition device, and the ignition negative pressure is controlled at-5.0 kPa.

[0051] Example 3

[0052] The homogenized sinter production process based on the ultra-thick material layer has the following process:

[0053] (1) Preparation of sintering mixture:

[0054] The sintering mixture is composed of iron-containing raw materials, fluxes, fuels and return fines. The iron-containing raw materials include iron-containing powder and dust, and the mass fraction in the mixture is 79.6%; the flux is active lime, the CaO content is 93.85%, the activity is 335 mL, and the mass fraction in the mixture is 4.4%; the fuel is composed of coke powder and coal powder, and the mass fraction is 4.0%; the mass fraction of the return fines is 12%.

[0055] (2) Mixing and balling of mixture:

[0056] The prepared sintering mixture is transported to a mixing and balling system for mixing and balling, the mixing and balling time is 8.04 min, the moisture content of the mixture after mixing and balling is controlled to be 7.5%, and the proportion of the particle size > 3 mm in the mixture after mixing and balling is 76.44%.

[0057] (3) Mixture distribution:

[0058] The bottom material is laid at the bottom of the sintering machine trolley, and a shuttle distributor and a nine-roller distributor are used for combined distribution. The particle size range of the bottom material is 10-16 mm, and the laying thickness of the bottom material is 60 mm; the thickness of the material layer after distribution is 950 mm; the distribution system is as follows:

[0059] The stroke of the shuttle distributor is 6 m; the mixed material bin level is 1 / 2; the valve opening control is 40%; and the nine-roller speed is 30 hz.

[0060] (4) Ignition sintering:

[0061] The ignition device is used to ignite and sinter the surface mixed material of the trolley, and the ignition negative pressure is controlled at-5.0 kPa.

[0062] Example 4

[0063] The homogenized sinter production process based on the ultra-thick material layer has the following process:

[0064] (1) Preparation of sintering mixed material:

[0065] The sintering mixed material is composed of iron-containing raw materials, fluxes, fuels and return fines. Among them, the iron-containing raw materials include iron-containing powder and dust, and the mass fraction in the mixed material is 78.3%; the flux is active lime, the CaO content is 93.45%, the activity is 344 mL, and the mass fraction in the mixed material is 4.2%; the fuel is composed of coke powder and coal powder, and the mass fraction is 4.5%; the mass fraction of return fines is 13%.

[0066] (2) Mixing and balling of mixed material:

[0067] The prepared sintering mixed material is transported to the mixing and balling system for mixing and balling, the mixing and balling time is 7.78 min, the water content of the mixed material after mixing and balling is controlled at 7.9%, and the proportion of particle size >3 mm in the mixed material after mixing and balling is 76.23%.

[0068] (3) Mixed material distribution:

[0069] The bottom material is laid at the bottom of the sintering machine trolley, and a shuttle distributor and a nine-roller distributor are used for combined distribution. The particle size range of the bottom material is 10-16 mm, and the laying thickness of the bottom material is 70 mm; the thickness of the material layer after distribution is 950 mm; the distribution system is as follows:

[0070] The stroke of the shuttle distributor is 6 m; the mixed material bin level is 1 / 2; the valve opening control is 40%; and the nine-roller speed is 30 hz.

[0071] (4) Ignition sintering:

[0072] The surface layer mixture of the pallet is ignited and sintered by the ignition device, and the ignition negative pressure is controlled at-5.0 kPa.

[0073] In order to further verify the reliability of the present application, the inventors carried out a series of tests, as follows:

[0074] 1. Research background and purpose

[0075] When the sintering layer thickness exceeds 900 mm, it is generally considered as super-thick layer sintering. Super-thick layer sintering technology has the advantages of reducing the sintering solid fuel ratio, reducing the sintering return ore rate, improving the mineral crystallization and sinter particle composition, etc. However, there are also some disadvantages, such as intensified pallet material segregation, aggravated edge effect, excessive heat at the lower part of the pallet and insufficient heat at the upper part, etc., which will lead to large differences in sinter strength and composition in different parts of the pallet.

[0076] In view of this, the research team proposes a homogeneous sinter production process based on super-thick layer using full active lime for digestion, in order to reduce the negative effects of super-thick layer sintering and enhance the positive effects of energy saving and strength improvement, and ultimately achieve the purpose of improving the drum strength of sinter, reducing the return ore rate and reducing the sinter solid fuel consumption.

[0077] 2. Sintering process flow

[0078] (1) Preparation of sintering mixture:

[0079] The sintering mixture is composed of iron-containing raw materials, flux, fuel and return ore. Among them, the iron-containing raw materials include imported powder, domestic powder, recycled resources, etc. (the imported powder mainly includes Brazilian ore (BRBF, high-silicon Ba coarse powder, Ka powder, etc.), Australian ore (SP10 powder, MacK powder, FMG mixed powder, super special powder, Silk Road powder, etc.) and other regional ore powder (Indian powder, South African powder, Russian powder, etc.); the domestic powder mainly includes 62 iron concentrate powder, magnetite powder, brown iron powder, 50 medium powder, etc.; the recycled resources mainly include magnetic separation powder and iron powder); the mass fraction in the mixture is 66% to 80%; the flux is active lime, with CaO content above 90% and activity above 310 mL, and the mass fraction in the mixture is 3.5% to 5%; the fuel includes anthracite and powder coke, with a mass fraction of 3.6% to 4.7%; the mass fraction of return ore is 10.6% to 15.5%.

[0080] (2) Mixing and balling of mixture:

[0081] The prepared sintering mixture is transported to the mixing and balling system for mixing and balling, and the moisture content of the mixed and balled mixture is controlled within the range of 6.5% to 8.3%, and the proportion of particle size > 3 mm in the mixed and balled mixture is above 70%.

[0082] (3) Mixture distribution:

[0083] The bottom material is laid at the bottom of the sintering machine trolley, and a shuttle distributor is combined with a nine-roll distributor for distribution. The particle size range of the bottom material is 10-16 mm, and the laying thickness of the bottom material is 40-80 mm; the material layer thickness after distribution is 920-1000 mm; the distribution system is as follows:

[0084] The stroke of the shuttle distributor is 5.5-6 m; the mixed ore bin level is 1 / 3-1 / 2; the damper opening control is 30%-60%; and the nine-roll speed is 20-40 hz.

[0085] (4) Ignition sintering:

[0086] The ignition device is used to ignite and sinter the surface layer of the mixed material, and the ignition negative pressure is controlled at-5.0 to-8.0 kPa.

[0087] Quicklime belongs to a sintering intensifier in the production process of sintered ore, and is widely studied by iron smelting workers as an essential part of the flux structure. When lime is in contact with water in the mixed material and digested, a large amount of heat will be released, which will increase the temperature of the sintering layer, reduce the over-wet layer, and thus improve the permeability of the sintering layer. In this process, lime slurry particles with condensation effect are generated, which promote the granulation of the mixed material, improve the granulation effect of the mixed material, increase the strength of the sintered granules, and improve the hot permeability of the sintering layer, laying a foundation for the ultra-thick layer sintering process in the iron smelting process. The research team uses active quicklime in the sintering process to test the changes of sintering process parameters and sinter quality before and after the implementation of ultra-thick layer production, and compares and analyzes the process parameters such as lime digestion dust removal, granulation effect, sintering machine operation parameters, and sinter quality.

[0088] 3.1 Quicklime activity test

[0089] The active quicklime used in production has a CaO content of 90.92% or more. Among them, the CaO content tested by the stone and steel smelting reaches 93.45% or more, and the activity reaches 335 mL or more. The quicklime activity test is shown in Table 1.

[0090] Table 1 Quicklime activity test

[0091]

[0092] 3.2 Quicklime digestion dust removal system adaptability

[0093] In the early production practice, the temperature of the circulating water of the lime dusting digestion system was measured every 3 hours, and compared with the baseline before the production of the super-thick layer. The results showed that after using the quicklime, the circulating water temperature of the lime dusting system increased, compared with the baseline before the production of the super-thick layer (820mm layer thickness), the average temperature increased by 11℃, the highest increased by 23℃, and the highest water temperature was 78℃. The change of the circulating water temperature of the lime dusting system before and after the production of the super-thick layer is shown in Table 2.

[0094] Table 2 Change of circulating water temperature of lime dusting system before and after production of super-thick layer

[0095]

[0096] 3.3 Mixed material granulation

[0097] Before and after the implementation of the super-thick layer production, the mixed material was sieved at the outlet of the secondary mixing. The results showed that after using the quicklime, the average particle size of the mixed material increased by 0.43mm, with an increase of 9.07%, and the proportion of particle size less than 3mm decreased by 7.32%, with a significant decrease. The particle size of the mixed material is shown in Table 3.

[0098] Table 3 Particle size of mixed material

[0099]

[0100] 3.4 Change of sintering system parameters

[0101] During the industrial production practice, part of the parameter data within 24 hours was collected (as shown in Table 4).

[0102] Table 4 Change of sintering parameters

[0103]

[0104]

[0105]

[0106] Note: The return ore level refers to the distance from the material surface to the top of the bin.

[0107] 4. Atomized water strengthening granulation technology

[0108] In the first and second mixing, atomized water nozzles were added, which could spray water into mist through compressed air. The mist water droplets were adsorbed on the surface of the mixed material particles, and through Van der Waals force, capillary action, etc., various mixed material particles were adhered together to form large mixed material particles, thereby strengthening the sintering granulation effect.

[0109] 5. Mixed material moisture optimization test

[0110] Under the same conditions of raw fuel, the original moisture of various materials is measured by oven 105±5℃, constant temperature 2h, the water addition is calculated according to the mixed material moisture 6.5%, 7.1%, 7.4%, 7.7%, 8.0%, 8.3%, after the sintering cup test, under the premise of considering the yield, drum strength, sintering productivity and other indicators, the mixed material moisture is controlled at 7.7% to 8.0%. Controlling the mixed particle moisture at a lower level is beneficial to reduce the consumption of sinter solid fuel, but the sintering productivity is low, the unit time output is reduced, and the sintering ton of ore power consumption and coal gas consumption rise.

[0111] 6. Ultra-thick layer sintering technical transformation implementation

[0112] 6.1 Sintering machine process equipment transformation

[0113] (1) Sintering machine trolley fence technical transformation

[0114] After the transformation, the sintering machine trolley fence is shown as Figure 1 , the sintering machine trolley fence is increased from 800mm before transformation to 920mm, mainly increasing the height of the uppermost section of the trolley fence, and the trolley fence is increased from 300mm before transformation to 420mm with less modification.

[0115] (2) Sintering machine electric fire technical transformation

[0116] The support leg of the sintering machine electric fire is increased by 150mm, so that the increased trolley fence is not hindered by the ignition furnace, and the external gas pipeline and combustion air pipe of the electric fire are lifted by 150mm and connected with the medium pipeline above the lifted electric fire.

[0117] (3) Sintering material distribution system technical transformation

[0118] After the trolley fence is increased, the nine-roller material distribution base is increased by 120mm, the mud roller material distributor is increased correspondingly, and the bottom of the mixed material bin is modified adaptively.

[0119] 6.2 On-site addition of wet dust collector to solve the problem of environmental pollution after adding on-site lime digestion

[0120] In the country, most of the sintering process in the steel plant has quicklime addition, in order to reduce environmental pollution, usually add dry ash, quicklime is not digested. Before the height of the trolley rail, in order to solve the problem of environmental pollution on site after the addition of quicklime digestion, the site is added with a more reliable wet dust collector for quicklime addition, which solves the problem of environmental pollution on site. Compared with dry ash, the proportion of less than 3mm particle size in the mixture is reduced by 3% to 8% after the addition of quicklime digestion, the sintering mixture permeability is improved, compared with dry ash, the sintering negative pressure is reduced by about 2000Pa, the loading capacity is increased by 3 to 5kg, which creates favorable conditions for increasing the thickness of the material layer, and the sintering endpoint temperature is increased by 30 to 50℃, the environmental pollution of quicklime addition site is greatly improved.

[0121] 6.3 Sintering machine air leakage control

[0122] (1) Improvement and overall replacement of trolley slide, machine head and tail sealing cover plate

[0123] The damaged trolley slide that has been in operation for a certain period of time is replaced during the maintenance time, and the new flexible sealing device of the sintering machine head is used to block the air leakage of this part. The flexible sealing device uses a number of narrow boards to form a complete sealing cover plate along the length direction of the trolley bottom beam, and each board is associated and floatingly arranged on the rack. Therefore, during operation, each board in the entire sealing cover plate can be attached to the trolley bottom beam, so as to realize good attachment of the entire sealing cover plate to the trolley bottom beam in the full length range, and reduce the air leakage of the machine head sealing cover plate.

[0124] (2) Coating high temperature resistant and erosion resistant material on the lining of trolley air tank

[0125] On the basis of welding steel bars and ring-shaped bones in the air tank, high temperature resistant and erosion resistant material is coated on the lining to reduce the leakage points in the trolley air tank.

[0126] (3) Replacement and repair of air tank stand pipe

[0127] According to the damage condition of the air tank stand pipe, the air tank stand pipe is replaced or repaired to minimize the air leakage of the air tank stand pipe.

[0128] (4) Adding high temperature resistant sealing material outside the sintering large flue corrugated expansion joint

[0129] The sintering large flue corrugated expansion joint of Shuigang sintering machine has been worn thin and leaked to varying degrees. If the entire expansion joint is replaced, the workload is large and the cost is relatively high. Shuigang adds flexible high temperature resistant sealing material outside the large flue expansion joint, which solves the problem of air leakage of the corrugated expansion joint.

[0130] (5) Welding repair of the vulnerable parts of the electric precipitator shell of the machine head

[0131] In view of the air leakage problem of the electric precipitator shell of the machine head, Shuigang organized construction forces to uniformly weld the worn parts of the electric precipitator shell of the machine head, thus solving the air leakage problem of the electric precipitator of the machine head.

[0132] 7. Technical indexes of sintering production

[0133] The technical indexes of sintering production and the metallurgical properties of sinter of examples 1-4 are shown in Table 5.

[0134] Table 5. Technical indexes of sintering production and metallurgical properties of sinter

[0135]

[0136] As can be seen from the results, by implementing the technical scheme of the present research and combining with the improvement of the corresponding process equipment, the yield and drum index of the sinter are both high, reaching 84.7% and 83.25% respectively in the examples of the present research, and the sintering power consumption is low (reaching 21.61 kwh / t at the lowest in the examples of the present research). It is proved that the homogeneous sinter production process based on the ultra-thick layer proposed in the present research can improve the drum strength of the sinter and reduce the return ore rate and sinter solid fuel consumption while realizing the production of the ultra-thick layer, and has great popularization and application value.

[0137] Although the present application has been described in detail in the foregoing general description, specific embodiments and experiments, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application all belong to the scope of protection required by the present application.

Claims

1. A homogeneous sintered ore production process based on an ultra-thick material layer, characterized in that: The steps include: Preparation of S1 sintering mixture: The iron-containing raw material, flux, fuel and return ore are mixed; wherein the flux is activated quicklime, the CaO content of which is above 90% and the activity is above 310mL; S2 mixed material is mixed and pelletized: The mixed material prepared in step S1 is conveyed to the mixing and pelletizing system for mixing and pelletizing, so that the moisture content of the mixed material after mixing and pelletizing is controlled at 6.5% to 8.3%, and the proportion of particles with a size greater than 3 mm in the mixed material after mixing and pelletizing reaches more than 70%; S3 Mixed Fabric: The base material is laid on the bottom of the sintering machine trolley and the material is distributed by a shuttle distributor, mud roller and nine-roller distributor; S4 ignition sintering: The surface mixture of the trolley is ignited and sintered by an ignition device.

2. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In the preparation of the sintering mixture in step S1, the iron-containing raw materials include iron-containing ore powder and dust ash, and the mass ratio of the iron-containing raw materials in the total mixture is 66% to 80%.

3. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In the preparation of the sintering mixture in step S1, the mass ratio of the flux active quicklime in the total mixture is 3.5% to 5%.

4. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In the preparation of the sintering mixture in step S1, the fuel is any one or both of anthracite and pulverized coke, and the mass ratio of the fuel in the total mixture is 3.6% to 4.7%.

5. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In the sintered mixture of step S1, the mass ratio of the return ore in the total mixture is 10.6% to 15.5%.

6. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: The time for mixing and pelletizing the mixed material in step S2 is more than 7.64 minutes.

7. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In step S2, the mixture is mixed and pelletized, and the moisture content of the mixture after mixing and pelletizing is controlled to be 7.7% to 8.0%.

8. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1 is characterized in that: In step S3, the particle size range of the base material in the mixed material spreading is 10-16 mm, the laying thickness of the base material is 40-80 mm, and the thickness of the material layer after spreading is 920-1000 mm.

9. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1, characterized in that: The distribution system in step S3 of the mixture distribution is as follows: the shuttle distributor stroke is: 5.5-6m; the material level of the mixture ore bin is: 1 / 3-1 / 2; the valve opening control is: 30%-60%; the nine-roller speed is: 20-40hz.

10. The homogeneous sintered ore production process based on ultra-thick material layer according to claim 1, characterized in that: During the ignition and sintering in step S4, the ignition negative pressure is controlled at -5.0 to -8.0 kPa.

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