CN110342845B - Method for manufacturing sand by using iron tailing slag - Google Patents
Method for manufacturing sand by using iron tailing slag Download PDFInfo
- Publication number
- CN110342845B CN110342845B CN201910531520.8A CN201910531520A CN110342845B CN 110342845 B CN110342845 B CN 110342845B CN 201910531520 A CN201910531520 A CN 201910531520A CN 110342845 B CN110342845 B CN 110342845B
- Authority
- CN
- China
- Prior art keywords
- particles
- tailing slag
- sand
- iron tailing
- magnetic separation
- 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.)
- Expired - Fee Related
Links
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 102
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 51
- 239000004576 sand Substances 0.000 title claims abstract description 44
- 239000002893 slag Substances 0.000 title claims abstract description 36
- 238000000034 method Methods 0.000 title claims abstract description 16
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 238000005469 granulation Methods 0.000 claims abstract description 16
- 230000003179 granulation Effects 0.000 claims abstract description 16
- 238000012216 screening Methods 0.000 claims abstract description 13
- 238000002360 preparation method Methods 0.000 claims abstract description 8
- 239000002245 particle Substances 0.000 claims description 77
- 238000007885 magnetic separation Methods 0.000 claims description 35
- 238000005245 sintering Methods 0.000 claims description 21
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 15
- 238000002156 mixing Methods 0.000 claims description 14
- 239000000843 powder Substances 0.000 claims description 13
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 10
- 238000003756 stirring Methods 0.000 claims description 7
- 238000001035 drying Methods 0.000 claims description 6
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 5
- 239000000920 calcium hydroxide Substances 0.000 claims description 5
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 5
- 238000000227 grinding Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 6
- 238000004064 recycling Methods 0.000 abstract 1
- 239000000126 substance Substances 0.000 description 8
- 239000008187 granular material Substances 0.000 description 4
- 238000009825 accumulation Methods 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 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
- 239000012466 permeate Substances 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/02—Agglomerated materials, e.g. artificial aggregates
- C04B18/021—Agglomerated materials, e.g. artificial aggregates agglomerated by a mineral binder, e.g. cement
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/12—Waste materials; Refuse from quarries, mining or the like
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Civil Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Mining & Mineral Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention relates to a method for preparing sand by using iron tailing slag, which comprises the steps of screening, preparing hydrated gel, granulating, preparing and the like, the utilization rate of the iron tailing slag can reach 100 percent by using the method, sand with different specifications can be formed after granulation and preparation, natural sand and machine-made sand can be completely replaced, the problems of sand resource exhaustion and the like can be solved, the comprehensive utilization rate of the iron tailing slag can be improved, a series of problems caused by iron tailing slag stockpiling can be solved, the feasibility is strong in the process of solving the problems of iron tailing slag recycling, sand resource exhaustion and the like, and a very ideal effect can be generated.
Description
Technical Field
The invention relates to a method for manufacturing sand by using iron tailing slag.
Background
With the continuous promotion of the steel industry and the mineral processing technology in China, the accumulation amount of the iron tailings reaches more than 50 hundred million tons, and the iron tailings are continuously discharged in the amount of about 1.5 hundred million tons every year, but the comprehensive utilization rate of the iron tailings in China is only 7 percent, and the long-term stacking of the iron tailings can cause the problems of large land occupation, environmental pollution, ecological damage and the like, the above problems can be solved if the iron tailings can be used instead of natural sand and mechanical sand, but since the particle size of the iron tailings is generally 0.001 to 1mm, the method has the advantages that the coarse grains of the sand in the building are less, the specification is single, the sand is not suitable for being used independently, the utilization rate of the iron tailings is low, the existing using mode is generally used by being mixed with machine-made sand, the problems of ecological damage, production cost increase and the like exist, and therefore, whether the existing mode can produce ideal effects or not is further discussed.
Disclosure of Invention
The invention aims to provide a method for manufacturing sand by using iron tailings, which solves the problems of low utilization rate of the iron tailings, environmental pollution, ecological damage, land encroachment, high production cost and the like by using a mode of completing granulation by using the characteristics of the iron tailings.
The method for manufacturing the sand by using the iron tailing slag comprises the following steps: screening: screening the iron tailing slag, and screening the screened iron tailing slag into two parts with the grain size of 0.001-0.2mm and the grain size of 0.2-1 mm; preparing hydrated gel: carrying out first magnetic separation on particles with the particle size of 0.001-0.2mm by using magnetic separation equipment; after the first magnetic separation is finished, putting the part of particles into sintering equipment for sintering, wherein the sintering temperature is 800-1300 ℃, after the sintering is finished, carrying out second magnetic separation on the part of particles through the magnetic separation equipment again, after the magnetic separation is finished again, grinding the part of particles into powder with the particle size of 3-90 mu m, and then adding 1-5% of regulator into the powder to form hydrated gel; and (3) granulation: putting the hydrated gel and the particles with the particle size of 0.2-1mm into a granulation device with the pressure of 8-15MPa according to the proportion of 1:4 for mixed granulation, and drying at normal temperature to form finished coarse sand particles with the particle size of 1-3 mm; preparation: and then mixing the finished coarse sand particles and the iron tailing slag according to the ratio of 2:3 to prepare the iron tailing slag finished sand.
In the preparation step, the coarse sand particles and the particles with the particle size of 0.2-1mm can be mixed and prepared according to the proportion of 1: 4.
The regulator comprises sodium hydroxide, calcium sulfate and calcium hydroxide which are prepared in equal molar number.
The method for manufacturing the sand by using the iron tailing slag provided by the invention comprises the steps of preparing hydrated gelled substance by using iron tailing slag particles with the particle size of 0.001-0.2mm, mixing and granulating the hydrated gelled substance and the iron tailing slag particles with the particle size of 0.2-1mm to form coarse sand particles with the particle size of 1-3mm which meet the building requirements, and mixing and preparing to form finished sand with particles of different specifications. In the process of preparing the hydrated gel, part of iron can be selected by first magnetic separation, the ferric oxide contained in the hydrated gel can be oxidized and reduced into ferroferric oxide after sintering, and the part of iron can be selected by second magnetic separation, so that the iron content in the hydrated gel can be effectively reduced, a large amount of iron can be recovered, and when the particle size of the hydrated gel is 3-90 mu m, the hydrated gel has better activity, better adsorption and gelling effects and more ideal effect during mixing and granulation; meanwhile, during granulation, moisture in the granules is evaporated outwards in the drying process to form air holes on the surfaces of the granules, so that concrete, mortar and the like can permeate inwards in use, and the granules have better occlusal force and higher strength after being built and have similar structures to natural sand; the regulator can regulate the strength grade of the hydrated gel; the method can completely utilize the iron tailing slag to complete the process of manufacturing the sand, and the manufactured sand has higher compressive strength and mechanical strength, can replace natural sand to solve the problems of resource exhaustion and the like, can solve a series of problems caused by low utilization rate of the iron tailing slag and long-term accumulation, and has very ideal technical effect.
The specific implementation mode is as follows:
example 1
Firstly, screening iron tailing slag, and screening the screened iron tailing slag into two parts with the grain size of 0.001-0.2mm and the grain size of 0.2-1 mm; then putting the particles with the particle size of 0.001-0.2mm into magnetic separation equipment through the magnetic separation equipment for first magnetic separation; after the first magnetic separation is finished, putting the part of particles into sintering equipment for sintering, wherein the sintering temperature is 1050 ℃, after the sintering is finished, carrying out second magnetic separation on the part of particles through the magnetic separation equipment again, grinding the part of particles after the magnetic separation is finished again into powder with the particle size of 60 mu m, then adding a regulator consisting of three substances of sodium hydroxide, calcium sulfate and calcium hydroxide into the powder, wherein the three substances are prepared according to equal molar number, the total amount of the regulator is 3% of the mass of the powder, and uniformly stirring to form a hydrated gel; adding 10-12% of water by mass into the hydrated gel, uniformly stirring, mixing with particles with the particle size of 0.2-1mm according to the proportion of 1:4, then putting into a granulation device with the pressure of 12MPa for mixing and granulation, wherein the particle size of the produced particles is 1-3mm, and drying at normal temperature to form finished coarse sand particles; and mixing the finished coarse sand particles and the iron tailing slag according to the ratio of 2:3 to obtain the iron tailing slag finished sand.
Example 2
Firstly, screening iron tailing slag, and screening the screened iron tailing slag into two parts with the grain size of 0.001-0.2mm and the grain size of 0.2-1 mm; then putting the particles with the particle size of 0.001-0.2mm into magnetic separation equipment through the magnetic separation equipment for first magnetic separation; after the first magnetic separation is finished, putting the partial particles into sintering equipment for sintering, wherein the sintering temperature is 800 ℃, after the sintering is finished, carrying out second magnetic separation on the partial particles through the magnetic separation equipment again, after the magnetic separation is finished again, grinding the partial particles into powder with the particle size of 3 mu m, then adding a regulator consisting of three substances of sodium hydroxide, calcium sulfate and calcium hydroxide into the powder, wherein the three substances are prepared according to equal molar number, the total amount of the regulator is 1% of the mass of the powder, and uniformly stirring to form a hydrated gel; adding 10-12% of water by mass into the hydrated gel, uniformly stirring, mixing with particles with the particle size of 0.2-1mm according to the proportion of 1:4, then putting into a granulation device with the pressure of 8MPa for mixing and granulation, wherein the particle size of the produced particles is 1-2mm, and drying at normal temperature to form finished coarse sand particles; and mixing the finished coarse sand particles and the iron tailing slag according to the ratio of 2:3 to obtain the iron tailing slag finished sand.
Example 3
Firstly, screening iron tailing slag, and screening the screened iron tailing slag into two parts with the grain size of 0.001-0.2mm and the grain size of 0.2-1 mm; then putting the particles with the particle size of 0.001-0.2mm into magnetic separation equipment through the magnetic separation equipment for first magnetic separation; after the first magnetic separation is finished, putting the partial particles into sintering equipment for sintering, wherein the sintering temperature is 1300 ℃, after the sintering is finished, carrying out second magnetic separation on the partial particles through the magnetic separation equipment again, after the magnetic separation is finished again, grinding the partial particles into powder with the particle size of 90 mu m, then adding a regulator consisting of three substances of sodium hydroxide, calcium sulfate and calcium hydroxide into the powder, wherein the three substances are prepared according to equal molar number, the total amount of the regulator is 5% of the mass of the powder, and uniformly stirring to form a hydrated gel; adding 10-12% of water by mass into the hydrated gel, uniformly stirring, mixing with particles with the particle size of 0.2-1mm according to the proportion of 1:4, then putting into a granulation device with the pressure of 15MPa for mixing and granulation, wherein the particle size of the produced particles is 2-3mm, and drying at normal temperature to form finished coarse sand particles; and mixing the finished coarse sand particles and the iron tailing slag according to the ratio of 2:3 to obtain the iron tailing slag finished sand.
Example 4
In the preparation step of the embodiment, finished coarse sand particles with the particle size of 1-3mm and iron tailing slag with the particle size of 0.2-1mm are mixed according to the proportion of 1:4 for preparation, and other steps are the same as the steps in the embodiment 1-3; the difference of this embodiment lies in that the proportion that has changed the granule of bigger particle size in iron tailing sediment finished sand is compared, further provides the finished sand of different usage.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (2)
1. The method for manufacturing the sand by using the iron tailing slag is characterized in that: the method comprises the following steps:
screening: screening the iron tailing slag, and screening the screened iron tailing slag into two parts with the grain size of 0.001-0.2mm and the grain size of 0.2-1 mm;
preparing hydrated gel: carrying out first magnetic separation on particles with the particle size of 0.001-0.2mm by using magnetic separation equipment; after the first magnetic separation is finished, putting the part of particles into sintering equipment for sintering, wherein the sintering temperature is 800-1300 ℃, after the sintering is finished, carrying out second magnetic separation on the part of particles through the magnetic separation equipment again, after the magnetic separation is finished again, grinding the part of particles into powder with the particle size of 3-90 mu m, and then adding 1-5% of regulator into the powder to form hydrated gel;
and (3) granulation: adding 10-12% of water by mass into the hydrated gel, uniformly stirring, putting the hydrated gel and particles with the particle size of 0.2-1mm into a granulation device with the pressure of 8-15MPa according to the proportion of 1:4 for mixed granulation, and drying at normal temperature to form finished coarse sand particles with the particle size of 1-3 mm;
preparation: then mixing the finished coarse sand particles and the iron tailing slag according to the proportion of 2:3 to obtain iron tailing slag finished sand;
the regulator comprises sodium hydroxide, calcium sulfate and calcium hydroxide which are prepared in equal molar number.
2. The method of claim 1, wherein: in the preparation step, coarse sand particles and particles with the particle size of 0.2-1mm are mixed according to the proportion of 1:4 for preparation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910531520.8A CN110342845B (en) | 2019-06-19 | 2019-06-19 | Method for manufacturing sand by using iron tailing slag |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910531520.8A CN110342845B (en) | 2019-06-19 | 2019-06-19 | Method for manufacturing sand by using iron tailing slag |
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| Publication Number | Publication Date |
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| CN110342845A CN110342845A (en) | 2019-10-18 |
| CN110342845B true CN110342845B (en) | 2022-02-18 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910531520.8A Expired - Fee Related CN110342845B (en) | 2019-06-19 | 2019-06-19 | Method for manufacturing sand by using iron tailing slag |
Country Status (1)
| Country | Link |
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| CN (1) | CN110342845B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112250335A (en) * | 2020-11-02 | 2021-01-22 | 赵生荣 | Energy-saving recovery-based method for manufacturing inert filler balls of waste slag |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62153153A (en) * | 1985-12-26 | 1987-07-08 | 日本磁力選鉱株式会社 | Coagulating method using converter collected dust as binder |
| CN101746981A (en) * | 2008-12-16 | 2010-06-23 | 长春金世纪矿业技术开发有限公司 | Light-weight insulating brick of tailings |
| CN102659360A (en) * | 2012-04-24 | 2012-09-12 | 武汉工程大学 | Iron tailing steam curing brick and preparation method thereof |
| CN103801548A (en) * | 2013-12-24 | 2014-05-21 | 中钢集团武汉安全环保研究院有限公司 | Gradient utilization method of high-sulfur low-silicon iron tailings |
| CN107721303A (en) * | 2017-10-09 | 2018-02-23 | 大连地拓环境科技有限公司 | A kind of iron tailings is granulated water-permeable brick and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5459655B2 (en) * | 2008-07-18 | 2014-04-02 | Ｊｆｅスチール株式会社 | How to treat tailings |
| CN108979713B (en) * | 2018-08-01 | 2019-11-05 | 辽宁工程技术大学 | A kind of processing of tailing and placement method |
-
2019
- 2019-06-19 CN CN201910531520.8A patent/CN110342845B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62153153A (en) * | 1985-12-26 | 1987-07-08 | 日本磁力選鉱株式会社 | Coagulating method using converter collected dust as binder |
| CN101746981A (en) * | 2008-12-16 | 2010-06-23 | 长春金世纪矿业技术开发有限公司 | Light-weight insulating brick of tailings |
| CN102659360A (en) * | 2012-04-24 | 2012-09-12 | 武汉工程大学 | Iron tailing steam curing brick and preparation method thereof |
| CN103801548A (en) * | 2013-12-24 | 2014-05-21 | 中钢集团武汉安全环保研究院有限公司 | Gradient utilization method of high-sulfur low-silicon iron tailings |
| CN107721303A (en) * | 2017-10-09 | 2018-02-23 | 大连地拓环境科技有限公司 | A kind of iron tailings is granulated water-permeable brick and preparation method thereof |
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| CN110342845A (en) | 2019-10-18 |
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Granted publication date: 20220218 |