CN221275847U - Rotary hearth furnace treatment system for metallurgical dust and mud - Google Patents
Rotary hearth furnace treatment system for metallurgical dust and mud Download PDFInfo
- Publication number
- CN221275847U CN221275847U CN202322861640.9U CN202322861640U CN221275847U CN 221275847 U CN221275847 U CN 221275847U CN 202322861640 U CN202322861640 U CN 202322861640U CN 221275847 U CN221275847 U CN 221275847U
- Authority
- CN
- China
- Prior art keywords
- hearth furnace
- rotary hearth
- mud
- metallurgical dust
- pellets
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000000428 dust Substances 0.000 title claims abstract description 115
- 239000008188 pellet Substances 0.000 claims abstract description 77
- 239000004115 Sodium Silicate Substances 0.000 claims abstract description 32
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims abstract description 32
- 229910052911 sodium silicate Inorganic materials 0.000 claims abstract description 32
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- 230000009467 reduction Effects 0.000 claims description 41
- 239000010802 sludge Substances 0.000 claims description 34
- 238000001238 wet grinding Methods 0.000 claims description 32
- 239000000203 mixture Substances 0.000 claims description 24
- 238000007599 discharging Methods 0.000 claims description 18
- 239000002918 waste heat Substances 0.000 claims description 13
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 11
- 239000003546 flue gas Substances 0.000 claims description 11
- 238000005453 pelletization Methods 0.000 claims description 9
- 238000003860 storage Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 abstract description 41
- 230000008569 process Effects 0.000 abstract description 28
- 239000011230 binding agent Substances 0.000 abstract description 24
- 238000010298 pulverizing process Methods 0.000 abstract description 21
- 239000002994 raw material Substances 0.000 abstract description 8
- 238000001035 drying Methods 0.000 abstract description 7
- 230000009471 action Effects 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 3
- 230000018044 dehydration Effects 0.000 abstract description 2
- 238000006297 dehydration reaction Methods 0.000 abstract description 2
- 230000000704 physical effect Effects 0.000 abstract description 2
- 239000011499 joint compound Substances 0.000 description 68
- 238000006722 reduction reaction Methods 0.000 description 40
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 20
- 230000002829 reductive effect Effects 0.000 description 17
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 14
- 239000011701 zinc Substances 0.000 description 13
- 229910052725 zinc Inorganic materials 0.000 description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 12
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 11
- 229910000831 Steel Inorganic materials 0.000 description 11
- 239000011575 calcium Substances 0.000 description 11
- 229910052791 calcium Inorganic materials 0.000 description 11
- 229910052799 carbon Inorganic materials 0.000 description 11
- 239000000843 powder Substances 0.000 description 11
- 239000010959 steel Substances 0.000 description 11
- 229910052742 iron Inorganic materials 0.000 description 10
- 238000004519 manufacturing process Methods 0.000 description 9
- 230000029087 digestion Effects 0.000 description 7
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 7
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 6
- 239000000292 calcium oxide Substances 0.000 description 6
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 239000000377 silicon dioxide Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000000227 grinding Methods 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 239000002910 solid waste Substances 0.000 description 5
- 230000006835 compression Effects 0.000 description 4
- 238000007906 compression Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 238000001465 metallisation Methods 0.000 description 4
- 238000009628 steelmaking Methods 0.000 description 4
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 3
- 229920002472 Starch Polymers 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000003638 chemical reducing agent Substances 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 235000012239 silicon dioxide Nutrition 0.000 description 3
- 239000008107 starch Substances 0.000 description 3
- 235000019698 starch Nutrition 0.000 description 3
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 229910052918 calcium silicate Inorganic materials 0.000 description 2
- 235000012241 calcium silicate Nutrition 0.000 description 2
- JHLNERQLKQQLRZ-UHFFFAOYSA-N calcium silicate Chemical compound [Ca+2].[Ca+2].[O-][Si]([O-])([O-])[O-] JHLNERQLKQQLRZ-UHFFFAOYSA-N 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- BCAARMUWIRURQS-UHFFFAOYSA-N dicalcium;oxocalcium;silicate Chemical compound [Ca+2].[Ca+2].[Ca]=O.[O-][Si]([O-])([O-])[O-] BCAARMUWIRURQS-UHFFFAOYSA-N 0.000 description 2
- 230000036961 partial effect Effects 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 238000011946 reduction process Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 235000019976 tricalcium silicate Nutrition 0.000 description 2
- 229910021534 tricalcium silicate Inorganic materials 0.000 description 2
- 229910001341 Crude steel Inorganic materials 0.000 description 1
- 229920001353 Dextrin Polymers 0.000 description 1
- 239000004375 Dextrin Substances 0.000 description 1
- 229920000881 Modified starch Polymers 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 1
- 238000000498 ball milling Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 235000019425 dextrin Nutrition 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- -1 meanwhile Chemical compound 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 229920002401 polyacrylamide Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000009270 solid waste treatment Methods 0.000 description 1
- WGEATSXPYVGFCC-UHFFFAOYSA-N zinc ferrite Chemical compound O=[Zn].O=[Fe]O[Fe]=O WGEATSXPYVGFCC-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Abstract
The utility model discloses a rotary hearth furnace treatment system for metallurgical dust and mud, which changes the traditional raw material pretreatment mode, utilizes ball mill to moisten and grind, a disc balling machine to ball and a rotary hearth furnace to reduce and treat the metallurgical dust and mud, utilizes the moistened and ground to improve the physical properties of raw materials, and adds sodium silicate and water in the moistened and ground process, under the action of moisture, sodium silicate plays the role of a binder to obtain metallurgical dust and mud pellets with higher strength, thereby omitting a drying device of pellets, and then utilizes the rotary hearth furnace to realize dehydration and prereduction of the pellets, and further solves the problems of large consumption of the binder, high cost and high pulverization rate in the conventional rotary hearth furnace technology.
Description
Technical Field
The utility model belongs to the technical field of metallurgy and energy, and relates to a rotary hearth furnace treatment system for metallurgical dust and sludge.
Background
The iron and steel industry is an important basic industry for economic development of China, is also a large household of solid waste discharge, and can generate a large amount of metallurgical dust and mud dust in the smelting process. The total amount of various kinds of dust generated by iron and steel enterprises is generally 8% -15% of the iron and steel yield, and zinc-containing dust accounts for about 20% -30%. In 2021, the yield of crude steel in the whole country exceeds 10.3 hundred million tons, so that zinc-containing dust generated in 2021 exceeds over 2000 ten thousand tons, and therefore, how to reasonably dispose metallurgical dust and sludge is already a key for sustainable development of the steel industry.
In the current mode of treating metallurgical dust and mud, the rotary hearth furnace has the advantages of higher adaptability, high reliability, easy operation and maintenance, relatively smaller environmental pollution, higher application value, suitability for the flow production of iron and steel enterprises, certain defects, complex raw material types, the need of pretreatment on the raw materials, the need of adding a large amount of binders in the forming process, poorer pellet quality, higher pellet pulverization rate in the reduction process, more than 20 percent, and high output of undersize powder, and finally the production cost of the rotary hearth furnace is greatly increased, and the production efficiency is reduced.
The Chinese patent application number CN201810482560.3 discloses a method for treating solid waste by a rotary hearth furnace, belongs to the technical field of solid waste treatment of steel plants, and solves the problems of low grade of zinc oxide powder recovered in the prior art and high pulverization rate of finished metallized pellets; the method for treating the solid waste by the rotary hearth furnace comprises the following steps: pelletizing, reducing and recovering zinc powder, and drying between pelletizing and reducing; the technology belongs to a conventional process for rotary hearth furnace production, which needs to consume a large amount of binder, and simultaneously produces undersize powder with higher pulverization rate.
Chinese patent application number CN202010622128.7 discloses a cold-pressed block for converter and its preparation method, the cold-pressed block for converter is composed of OG mud, metallized pellet undersize powder and binder, the weight ratio of OG mud to metallized pellet undersize powder is 70-90: 10-30, wherein the ratio of the weight of the binder to the sum of the weight of the OG mud and the weight of the metallized pellet undersize powder is 2-2.5%, the particle size of the OG mud is 0-5 mu m, and the particle size of the metallized pellet undersize powder is 0.02-5 mm; the particle size of the metallized pellet undersize powder is obviously larger than that of OG mud, and the metallized pellet undersize powder with a larger particle size structure can provide framework materials for the cold-pressed blocks for the converter, so that the primary strength of the cold-pressed blocks for the converter can be increased under the condition of smaller binder consumption, and the material returning rate of the cold-pressed blocks for the converter in the processing process can be reduced; however, this technique only provides a method of treating undersize powder of a rotary hearth furnace, and does not fundamentally inhibit the generation of undersize powder.
The Chinese patent application No. CN202010765310.8 discloses an organic binder and application thereof, wherein the organic binder at least comprises 60-80 parts of pregelatinized starch, 5-5 parts of polyacrylamide, 5-20 parts of white dextrin and 5-15 parts of cellulose derivative according to parts by weight. The organic binder provided by the utility model has long shelf life, can be used as an intermediate for utilizing solid waste, can obviously reduce production cost, has short period, is added in an amount of 2.5% of the mass of the iron-containing solid waste in a steelworks, can reach more than 300N after being rolled by 95 kg of pressure, can control the moisture content to be more than 2% after being dried at 200 ℃ for 25 minutes (assisted by adding 400 ℃ strong hot air), can reach more than 420N, can increase the ball yield of metallized pellets after being reduced at 1280 ℃ in a terminal rotary hearth furnace, effectively reduces the pulverization rate, and can reach more than 1800N. However, in the technology, the cost of the binder is high, and the pulverization rate is reduced only by improving the green ball strength, so that the effect is limited and the cost is high.
In view of the above, there is a need to develop a new method for treating metallurgical dust and sludge, which can solve the problems of large binder consumption, high cost and high pulverization rate in the conventional rotary hearth furnace process.
Disclosure of utility model
Aiming at the defects existing in the prior art, the utility model aims to provide a rotary hearth furnace treatment system for metallurgical dust and mud, which is characterized in that the metallurgical dust and mud is subjected to wet grinding through a ball mill, balling through a disc balling machine and reduction treatment through a rotary hearth furnace, the physical properties of raw materials are improved through wet grinding, sodium silicate and water are added in the wet grinding process, the sodium silicate plays a role of a binder under the action of moisture, and a metallurgical dust and mud ball with higher strength is obtained, so that a drying device for pellets is omitted, the rotary hearth furnace is utilized to realize dehydration and prereduction of the pellets, and the problems of large binder consumption, high cost and high pulverization rate in the conventional rotary hearth furnace process are solved.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
The utility model provides a rotary hearth furnace treatment system of metallurgical dust and sludge, which comprises a metallurgical dust and sludge bin, a sodium silicate bin, a water storage tank, a ball mill, a disc pelletizer and a rotary hearth furnace, wherein the rotary hearth furnace treatment system is used for treating the metallurgical dust and sludge;
the ball mill is respectively connected with the metallurgical dust and mud bin, the sodium silicate bin and the water storage tank, and is used for carrying out wet grinding on the metallurgical dust and mud, the sodium silicate and the water to obtain a mixture;
The disc pelletizer is connected with the ball mill through a belt and is used for pelletizing the mixture to obtain metallurgical dust and mud pellets;
The rotary hearth furnace is connected with the disc pelletizer through a belt and is used for carrying out reduction treatment on metallurgical dust and sludge pellets; the inside of the rotary hearth furnace is sequentially provided with a dewatering area, a pre-reduction area, a deep reduction area and a discharging area; and a flue gas pipeline is arranged above the dewatering area.
Preferably, the device also comprises a waste heat boiler, a dust remover and a chimney which are connected with a flue gas pipeline of the rotary hearth furnace; the waste heat boiler, the dust remover and the chimney are connected through pipelines.
The rotary hearth furnace treatment system for metallurgical dust and sludge provided by the utility model has the following beneficial effects:
1. According to the utility model, the traditional raw material pretreatment mode is changed, the metallurgical dust and mud is added into the ball mill, the physical characteristics of the metallurgical dust and mud are improved by a wet grinding method, so that free calcium is quickly digested, the particle size of the wet ground mixture is uniform and consistent, the forming is facilitated, the reducing agent carbon (the reducing agent carbon is carbon in the metallurgical dust and mud) can be uniformly dispersed into the material, the contact between the carbon and the iron-zinc oxide is increased, and the quick reduction reaction is facilitated;
2. According to the rotary hearth furnace treatment system for metallurgical dust and mud, water and sodium silicate are added in the ball milling process of the ball mill, and the sodium silicate plays a role of a binder under the action of moisture, so that a conventional starch binder is replaced, the production cost is greatly reduced, and the problems of high binder consumption, high cost and the like in the conventional rotary hearth furnace process are solved;
3. The rotary hearth furnace treatment system for metallurgical dust and sludge can solve the problems of slow digestion of free calcium, large consumption of binder, high cost and the like in the conventional rotary hearth furnace process;
4. According to the rotary hearth furnace treatment system for metallurgical dust and mud, the material performance is improved through wet grinding, and the proper additive sodium silicate is selected, so that the effects of binding agent and inhibiting pulverization are achieved, the cost of the traditional binding agent is reduced, the pellet drying process is omitted, the pulverization rate is effectively reduced, the production efficiency is improved, and the economic benefit is remarkably increased;
5. The rotary hearth furnace treatment system for metallurgical dust and mud can solve the problem of high pulverization rate of the rotary hearth furnace, and the undersize powder yield is reduced by 75% and the pulverization rate is reduced to below 5%;
6. According to the utility model, the material performance is improved by moistening and grinding and adding sodium silicate, the pellet strength is improved, the conventional starch binder and drying procedures are omitted, digestion and mixing are realized by a ball mill, reduction pulverization is reduced, the production procedure of a rotary hearth furnace raw material is changed, and a small amount of sodium silicate additive plays a role in the binder and also plays a role in reducing pulverization;
7. according to the rotary hearth furnace treatment system for metallurgical dust and mud, the performance of the metallurgical dust and mud is improved through the moistening and grinding in the ball mill, and the strength of pellets is improved, so that a drying device is omitted, a dewatering area, a pre-reduction area, a deep reduction area and a treatment area are arranged in the rotary hearth furnace, the pellets are dewatered and reduced in the rotary hearth furnace, and the energy consumption is saved.
Drawings
Other features, objects and advantages of the present utility model will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:
FIG. 1 is a schematic flow diagram of a rotary hearth furnace process for metallurgical dust and sludge of the present utility model;
FIG. 2 is a schematic diagram of the rotary hearth furnace treatment system for metallurgical dust and sludge of the present utility model.
Detailed Description
In order to better understand the above technical solution of the present utility model, the technical solution of the present utility model is further described below with reference to examples.
Referring to FIG. 1, the utility model provides a rotary hearth furnace treatment method for metallurgical dust and sludge, which comprises the following steps:
s1, adding metallurgical dust and mud into a ball mill for wet grinding, and adding sodium silicate and water into the ball mill in the wet grinding process to obtain a mixture;
Specifically, selecting a metallurgical dust and mud raw material of a steel plant, wherein the metallurgical dust and mud contains 45-50wt% of iron, 2-4wt% of zinc, 9-11wt% of carbon, 5-8wt% of water, 3-4wt% of silicon dioxide, 8-11wt% of calcium oxide and 2.5-3.5wt% of free calcium oxide; from the category, metallurgical dust is selected from the group consisting of LT ash, steel making sludge, blast furnace dry ash, gas sludge, electric furnace ash, converter secondary ash, and the like produced in steel works. The granularity of the metallurgical dust mud is 0.074-3 mm, and the binary alkalinity is 2.6-3.2.
Firstly, adding the metallurgical dust mud into a ball mill for wet grinding, wherein the mass ratio of the metallurgical dust mud to sodium silicate is 100:2.5 to 3.5, and simultaneously adding a certain amount of water into the ball mill to obtain the mixture with the water content of 8 to 11 weight percent. Wherein, sodium silicate is added in a solid form, the modulus N of the sodium silicate is 1.8-3.0, and the binary alkalinity of the metallurgical dust and mud added with the sodium silicate is 1.4-1.9. In the process of moistening and grinding, the moistening and grinding time is controlled to be 1.2-1.8 h, the specific surface area can be increased through a moistening and grinding process, the specific surface area of metallurgical dust and mud is increased from 1919-3200 cm 2/g to 4000-5000 cm 2/g, the activity of the mixture is further improved, free calcium in the mixture is quickly digested, the mixing uniformity reaches 99%, the solid sodium silicate is in close contact with the metallurgical dust and mud, and the bonding effect is high. After the wet grinding, the granularity of the obtained mixture is less than 0.0325mm, the specific surface area is 4000-5000 cm 2/g, the binary alkalinity is 1.6-1.8, and the digestion rate of free calcium is more than or equal to 80%.
In the wet grinding process, free calcium in the metallurgical dust mud is rapidly digested, and the digestion reaction is as follows: caO+H 2O＝Ca(OH)2.
S2, pelletizing the mixture by adopting a disc pelletizer to obtain metallurgical dust and mud pellets;
specifically, the mixture discharged from the ball mill is pelletized by a disc pelletizer, wherein sodium silicate plays a role of bonding, and the step of externally preparing a starch binder is omitted, so that metallurgical dust and mud pellets are obtained, wherein the falling strength of the metallurgical dust and mud pellets is more than 20 times, the falling strength of the metallurgical dust and mud pellets is improved by more than 4 times compared with the conventional process (the falling strength of the metallurgical dust and mud pellets is 0.5m and less than 5 times by using the conventional binder pellets), the compressive strength is more than 100N, the wet pellets prepared by the conventional process are improved by more than 2 times, and the pelletizing cost is reduced by 20 percent compared with the conventional pelleting process.
And S3, conveying the metallurgical dust and mud pellets into a rotary hearth furnace for reduction, and sequentially passing through a dewatering area, a pre-reduction area, a deep reduction area and a discharging area in the process of rotating the bottom of the rotary hearth furnace to obtain metallized pellets.
Specifically, due to the fact that the strength of the pellets prepared by adopting the wet grinding process is high, a drying device can be omitted, metallurgical dust and sludge pellets are directly fed into a rotary hearth furnace for reduction, wherein the rotary hearth furnace is divided into a dewatering area, a pre-reduction area, a deep reduction area and a discharging area, the wall body and the upper part of the rotary hearth furnace are fixed in the production process, the pellets rotate along with land, and the pellets sequentially pass through each area. In the rotating process of the bottom of the rotary hearth furnace, metallurgical dust and sludge pellets sequentially pass through a dewatering area, a pre-reduction area, a deep reduction area and a discharge area to finally obtain metallized pellets
In the reduction process of the rotary hearth furnace, the temperature of the dewatering area is 400-500 ℃, and the time of the metallurgical dust and mud pellet in the dewatering area is 5-10 min; under the temperature condition, the explosion caused by overlarge vapor pressure formed by removing moisture in the metallurgical dust and mud pellets can be effectively prevented. The temperature of the pre-reduction zone is 800-1000 ℃, and the time of the dehydrated metallurgical dust and sludge balls in the pre-reduction zone is 4-8 min; in the area, the metallurgical dust and mud pellet realizes the preliminary removal of zinc, meanwhile, ferric oxide in the metallurgical dust and mud pellet is prereduced into ferrous oxide, partial ferrous oxide reacts with sodium silicate and silicon dioxide in the metallurgical dust and mud to generate ferric silicate, and the ferric silicate is in a semi-liquid phase state under the temperature condition, so that the effect of adhering particles in the pellet can be realized, and the cracking and pulverization of the pellet are prevented. The temperature of the deep reduction zone is 1260-1280 ℃, and the time of the pre-reduced metallurgical dust and sludge ball in the deep reduction zone is 8-15 min; after the prereduced metallurgical dust and mud balls enter the area, ferrous oxide and ferric silicate are rapidly reduced into metallic iron by carbon and CO under the high-temperature condition, silica and calcium oxide further react to produce dicalcium silicate and tricalcium silicate phases, and the dicalcium silicate and tricalcium silicate phases are helpful for improving the strength of the metallized pellets, and meanwhile, residual zinc elements are further removed. The temperature of the discharging area is 900-1000 ℃, the time of the reduced metallized pellets in the discharging area is 3-5 min, and the reduced metallized pellets are discharged from the discharging area.
The mixing degree of the common mixing process is not more than 80%, and the mixing degree of the mixture reaches more than 99% by adopting a lubricating process, so that the reducing agent carbon can be more uniformly dispersed in a material system, the reduction reaction is promoted to be rapidly carried out, and the pulverization phenomenon caused by incomplete partial reduction of the carbon is avoided.
The compression strength of the prepared metallized pellet is more than 2000N, the metallization rate is more than 80%, the zinc removal rate is more than or equal to 90%, the pulverization rate is less than 5%, and the pulverization rate of the method is reduced by more than 75% compared with that of the conventional process to be less than 5%.
S4, recovering waste heat from high-temperature flue gas from the rotary hearth furnace, removing dust to obtain zinc-containing dust, and discharging the dust-removed flue gas from a chimney.
The utility model also provides a rotary hearth furnace treatment system for metallurgical dust and sludge for executing the rotary hearth furnace treatment method for metallurgical dust and sludge, which is shown in the figure 2, and comprises a metallurgical dust and sludge bin 1, a sodium silicate bin 2, a water storage tank 3, a ball mill 4, a disc pelletizer 5 and a rotary hearth furnace 6. The ball mill 4 is respectively connected with the metallurgical dust and mud bin 1, the sodium silicate bin 2 and the water storage tank 3, and the ball mill 4 is used for carrying out wet grinding on the metallurgical dust and mud, the sodium silicate and the water to obtain a mixture. The disc granulator 5 is connected to the ball mill 4 by means of a belt, which disc granulator 5 is used to granulate the mixture to obtain metallurgical dust and sludge pellets. The rotary hearth furnace 6 is connected with the disc pelletizer 5 through a belt and is used for carrying out reduction treatment on metallurgical dust and mud pellets; a dewatering area, a pre-reduction area, a deep reduction area and a discharging area are sequentially arranged in the rotary hearth furnace 6; a flue gas pipeline is arranged above the dewatering area.
Referring to fig. 2, the rotary hearth furnace treatment system for metallurgical dust and sludge further comprises a waste heat boiler 7, a dust remover 8 and a chimney 9 which are connected with a flue gas pipeline of the rotary hearth furnace 6; the waste heat boiler 7, the dust remover 8 and the chimney 9 are connected through pipelines.
A rotary hearth furnace treatment system for metallurgical dust and sludge in accordance with the present utility model is further described with reference to specific examples.
Example 1
The rotary hearth furnace treatment method for metallurgical dust and sludge in the embodiment comprises the following steps:
(1) The metallurgical dust and mud adopts blast furnace dry ash, steelmaking sludge, electric furnace ash, gas mud and converter secondary ash of the steel plant, and the components are as follows: 45% of iron, 2.3% of zinc, 9.5% of carbon, 5% of moisture, 8.5% of calcium oxide, 3% of silicon dioxide, 2.8% of binary alkalinity and 2.7% of free calcium. The granularity of the metallurgical dust mud is between 3mm and 0.074 mm.
(2) The metallurgical dust mud and sodium silicate are subjected to wet grinding by a ball mill according to the mass ratio of 100:3.5, a certain amount of water is added in the wet grinding process, the wet grinding time is 1.8h, the sodium silicate modulus N=1.8, the moisture content of the mixture obtained after the wet grinding is 8.8%, the binary alkalinity is 1.6, the granularity of the mixture is less than 0.0325mm after the wet grinding, the specific surface area is increased to 4900cm 2 from 3000cm 2 before the wet grinding, and the free calcium digestion rate reaches 80%.
(3) Pelletizing the mixture discharged from the ball mill by adopting a disc pelletizer to obtain metallurgical dust and mud pellets, wherein the falling strength of the metallurgical dust and mud pellets is 21.5 times, and the compressive strength of the metallurgical dust and mud pellets is 102N;
(4) The metallurgical dust and mud pellets enter a rotary hearth furnace for reduction, the temperature of a dewatering area of the rotary hearth furnace is controlled to be 400 ℃, the time of pellets in the dewatering area is controlled to be 9.5min, the temperature of a pre-reduction area is controlled to be 850 ℃, the time of pellets in the pre-reduction area is controlled to be 7.5min, the temperature of a deep reduction area is controlled to be 1280 ℃, the time of pellets in the deep reduction area is controlled to be 8min, the temperature of a discharging area is controlled to be 1000 ℃, the time of pellets in the discharging area is controlled to be 5min, and metallized pellets are discharged from the discharging area of the rotary hearth furnace; the high-temperature flue gas of the rotary hearth furnace is subjected to waste heat recovery through a waste heat boiler and then enters a dust remover for dust removal treatment, and is discharged through a chimney after reaching the standard.
The compression strength of the metallized pellets prepared in the embodiment is 2580N, the metallization rate is 85%, the zinc removal rate is 92%, and the pulverization rate is 4.7%.
Example 2
The rotary hearth furnace treatment method for metallurgical dust and sludge in the embodiment comprises the following steps:
(1) The metallurgical dust and mud adopts blast furnace dry ash, steelmaking sludge, LT ash, gas mud and converter secondary ash in the steel plant, and the components are as follows: the iron content is 47%, the zinc content is 3.2%, the carbon content is 10.2%, the moisture content is 6.4%, the calcium oxide content is 10.3%, the silica content is 3.3%, the binary alkalinity is 3.13, and the free calcium content is 3.3%. The granularity of the metallurgical dust mud is between 3mm and 0.074 mm.
(2) The metallurgical dust mud and sodium silicate are subjected to wet grinding by a ball mill according to the mass ratio of 100:3, a certain amount of water is added in the wet grinding process, the wet grinding time is 1.5h, the modulus of sodium silicate is N=2.4, the moisture content of the mixture obtained after the wet grinding is 9.7%, the binary alkalinity is 1.8, the granularity of the mixture after the wet grinding is less than 0.0325mm, the specific surface area is increased to 4500cm 2 from 2500cm 2 before the wet grinding, and the free calcium digestion rate is 82%.
(3) Pelletizing the mixture discharged from the ball mill by adopting a disc pelletizer to obtain metallurgical dust and mud pellets, wherein the falling strength of the metallurgical dust and mud pellets is 23.6 times, and the compressive strength is 104N;
(4) The metallurgical dust and mud pellets enter a rotary hearth furnace for reduction, the temperature of a dewatering area of the rotary hearth furnace is controlled to be 450 ℃, the time of pellets in the dewatering area is controlled to be 7min, the temperature of a pre-reduction area is controlled to be 930 ℃, the time of pellets in the pre-reduction area is controlled to be 6min, the temperature of a deep reduction area is controlled to be 1270 ℃, the time of pellets in the deep reduction area is controlled to be 12min, the temperature of a discharging area is controlled to be 980 ℃, the time of pellets in the discharging area is controlled to be 4min, and metallized pellets are discharged from the discharging area of the rotary hearth furnace; the high-temperature flue gas of the rotary hearth furnace is subjected to waste heat recovery through a waste heat boiler and then enters a dust remover for dust removal treatment, and is discharged through a chimney after reaching the standard.
The compression strength of the metallized pellets prepared in the embodiment is 2560N, the metallization rate is 83%, the zinc removal rate is 91%, and the pulverization rate is 4.5%.
Example 3
The rotary hearth furnace treatment method for metallurgical dust and sludge in the embodiment comprises the following steps:
(1) The metallurgical dust and mud adopts blast furnace dry ash, steelmaking sludge, LT ash and gas mud of a steel plant, and the components are as follows: the iron content was 49%, the zinc content was 3.8%, the carbon content was 11%, the moisture content was 8%, the calcium oxide content was 11%, the silica content was 3.9%, the binary alkalinity was 3.13, and the free calcium content was 3%. The granularity of the metallurgical dust mud is between 3mm and 0.074 mm.
(2) The metallurgical dust mud and sodium silicate are subjected to wet grinding by a ball mill according to the mass ratio of 100:2.5, a certain amount of water is added in the wet grinding process, the wet grinding time is 1.2h, the modulus of sodium silicate is N=3, the moisture content of the mixture obtained after the wet grinding is 11.5%, the binary alkalinity is 1.8, the granularity of the mixture after the wet grinding is less than 0.0325mm, the specific surface area is increased to 4200cm 2 from 2000cm 2 before the wet grinding, and the free calcium digestion rate reaches 85%.
(3) Pelletizing the mixture discharged from the ball mill by adopting a disc pelletizer to obtain metallurgical dust and mud pellets, wherein the falling strength of 0.5m is 24 times, and the compressive strength is 112N;
(4) The metallurgical dust and mud pellets enter a rotary hearth furnace for reduction, the temperature of a dewatering area of the rotary hearth furnace is controlled to be 500 ℃, the time of pellets in the dewatering area is controlled to be 5min, the temperature of a pre-reduction area is controlled to be 1000 ℃, the time of pellets in the pre-reduction area is controlled to be 4.5min, the temperature of a deep reduction area is controlled to be 1260 ℃, the time of pellets in the deep reduction area is controlled to be 15min, the temperature of a discharging area is controlled to be 900 ℃, the time of pellets in the discharging area is controlled to be 3min, and metallized pellets are discharged from the discharging area of the rotary hearth furnace; the high-temperature flue gas of the rotary hearth furnace is subjected to waste heat recovery through a waste heat boiler and then enters a dust remover for dust removal treatment, and is discharged through a chimney after reaching the standard.
The compression strength of the metallized pellets prepared in the embodiment is 242N, the metallization rate is 81%, the zinc removal rate is 90%, and the pulverization rate is 3.9%.
It will be appreciated by persons skilled in the art that the above embodiments are provided for illustration only and not for limitation of the utility model, and that variations and modifications of the above described embodiments are intended to fall within the scope of the claims of the utility model as long as they fall within the true spirit of the utility model.
Claims (2)
1. The rotary hearth furnace treatment system for metallurgical dust and sludge is characterized by comprising a metallurgical dust and sludge bin, a sodium silicate bin, a water storage tank, a ball mill, a disc pelletizer and a rotary hearth furnace;
the ball mill is respectively connected with the metallurgical dust and mud bin, the sodium silicate bin and the water storage tank, and is used for carrying out wet grinding on the metallurgical dust and mud, the sodium silicate and the water to obtain a mixture;
The disc pelletizer is connected with the ball mill through a belt and is used for pelletizing the mixture to obtain metallurgical dust and mud pellets;
The rotary hearth furnace is connected with the disc pelletizer through a belt and is used for carrying out reduction treatment on metallurgical dust and sludge pellets; the inside of the rotary hearth furnace is sequentially provided with a dewatering area, a pre-reduction area, a deep reduction area and a discharging area; and a flue gas pipeline is arranged above the dewatering area.
2. The rotary hearth furnace treatment system for metallurgical dust and sludge according to claim 1, further comprising a waste heat boiler, a dust remover and a chimney connected to the flue gas duct of the rotary hearth furnace; the waste heat boiler, the dust remover and the chimney are connected through pipelines.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322861640.9U CN221275847U (en) | 2023-10-25 | 2023-10-25 | Rotary hearth furnace treatment system for metallurgical dust and mud |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322861640.9U CN221275847U (en) | 2023-10-25 | 2023-10-25 | Rotary hearth furnace treatment system for metallurgical dust and mud |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN221275847U true CN221275847U (en) | 2024-07-05 |
Family
ID=91695213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322861640.9U Active CN221275847U (en) | 2023-10-25 | 2023-10-25 | Rotary hearth furnace treatment system for metallurgical dust and mud |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN221275847U (en) |
-
2023
- 2023-10-25 CN CN202322861640.9U patent/CN221275847U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2021115029A1 (en) | Iron-containing metallurgical slag granule graded waste heat recovery and direct reduction system and method | |
| CN106367600A (en) | Method for treating high-zinc iron-containing slime through utilizing rotary kiln | |
| CN102329909B (en) | Method for extracting iron particles and zinc powder from dust of steel and iron plant | |
| CN101892382B (en) | Method for extracting high-content nickel, chromium and iron from stainless steel dust | |
| CN112458279B (en) | Integrated process method of multi-hearth furnace and rotary hearth furnace | |
| CN112226615B (en) | Comprehensive utilization method of stainless steel solid waste | |
| WO2021244616A1 (en) | Two-step method for efficiently separating iron and phosphorus in high-phosphorus iron-bearing resource on basis of gas-based energy | |
| CN101671752B (en) | Method for producing directly reduced pellets by adding pore-forming agent and organic binder | |
| CN111647753B (en) | Method for recovering zinc by direct reduction of melting gasification furnace | |
| CN114540617A (en) | Preparation method and application method of redox briquetting of converter fly ash | |
| KR100568352B1 (en) | Ironmaking process with briquetting facility using fine iron and sludge | |
| CN221275847U (en) | Rotary hearth furnace treatment system for metallurgical dust and mud | |
| CN217351484U (en) | System for iron-containing zinc dust mud resource utilization | |
| CN101638703B (en) | Method for directly reducing nickel containing pig iron by lateritic nickel in tunnel kiln | |
| CN117265260A (en) | Rotary hearth furnace treatment method and system for metallurgical dust and sludge | |
| CN114057371B (en) | Sludge drying treatment method based on particle heat source | |
| CN212152365U (en) | Iron-containing material preheating and pre-reducing device | |
| CN103589865B (en) | Method for producing metallized pellets by direct reduction of powdered iron by carbon cycle oxygenation | |
| CN108609873B (en) | Silicon-carbon double-acidity composite pellet used in converter slag modification and preparation method thereof | |
| CN112811448A (en) | Recovery process of magnesium oxide reducing slag | |
| CN114574692B (en) | Preparation method of carbon-containing micro-electrolysis material | |
| CN206256138U (en) | The system that a kind of mill ore magnetic selection processes copper ashes | |
| CN114774683B (en) | System and method for recycling iron-zinc-containing dust mud | |
| CN116574914A (en) | Zinc-containing solid waste dust and sludge treatment method and system | |
| CN115652083B (en) | Multistage air inlet soaking reduction method for iron-containing material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant |