CN112143885B - Composite additive for iron ore pellets and iron ore pellets - Google Patents
Composite additive for iron ore pellets and iron ore pellets Download PDFInfo
- Publication number
- CN112143885B CN112143885B CN202010993394.0A CN202010993394A CN112143885B CN 112143885 B CN112143885 B CN 112143885B CN 202010993394 A CN202010993394 A CN 202010993394A CN 112143885 B CN112143885 B CN 112143885B
- Authority
- CN
- China
- Prior art keywords
- iron ore
- pellets
- green
- composite additive
- ore 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/14—Agglomerating; Briquetting; Binding; Granulating
- C22B1/24—Binding; Briquetting ; Granulating
- C22B1/242—Binding; Briquetting ; Granulating with binders
- C22B1/244—Binding; Briquetting ; Granulating with binders organic
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention belongs to the technical field of iron ore pellets, and mainly relates to a composite additive for iron ore pellets and the iron ore pellets, wherein the composite additive for iron ore pellets is prepared by uniformly mixing 30-50% of a tackifier, 10-20% of a reinforcer, 5-10% of polyethylene glycol and the balance of water according to the mass percentage. The additive is mixed into iron ore powder according to a certain proportion, fully and uniformly mixed, and then pelletizing is carried out in a disc pelletizer, and then green pellet strength detection is carried out. The additive can effectively improve the falling strength and compressive strength of green pellets and improve the quality of the green pellets.
Description
Technical Field
The invention belongs to the technical field of iron ore pellets, and mainly relates to a composite additive for iron ore pellets and the iron ore pellets.
Background
The pellet has the advantages of uniform granularity, high cold strength, high iron grade, good reducibility and the like, is an indispensable high-quality furnace charge, and has obvious positive effects on optimizing the structure of the furnace charge of the blast furnace, improving the economic indexes of the ironmaking technology, promoting energy conservation and consumption reduction and realizing environmental friendliness.
The pellet binder is a key auxiliary raw material for processing pellets in the steel industry, and the performance of the pellet binder is directly related to the quality of the pellets. Bentonite has been used as a pelletizing additive for decades, is a high-quality additive accepted by pellet manufacturers at home and abroad at present, can improve the falling strength of green pellets, particularly can improve the cracking temperature of the green pellets during drying, but because of the layered structure of the bentonite, a crystal layer contains a large amount of molecular bound water, and can absorb 600-700% of water, the green pellets are beneficial to being pelletized, but the wet strength and the cracking temperature of the green pellets during drying are limited, because the moisture is too high, the wet strength is reduced, the ore return rate is still 25-30% during the pelletizing process, and the drying speed is slower than that of other additives, namely the green pellets during drying. The yield is influenced and the energy consumption is increased. In addition, the main component of bentoniteThe main component is SiO 2 And Al 2 O 3 According to general experience, the grade of Fe contained in the pellet ore is reduced by 0.6 percent by adding 1 percent of bentonite. The percentage content of bentonite added to the pellets in China is 3% -5% on average, and the percentage content of bentonite added to the pellets in China is not lower than 2.5% in the case of less pellets, so that the iron-containing grade of the pellets is reduced, and the energy consumption and the yield of blast furnace smelting are influenced.
Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide the composite additive for the iron ore pellets and the iron ore pellets, wherein the composite additive can improve the compressive strength and the falling strength of green pellets and reduce the ore return rate of the iron ore pellets; the composite additive of the invention can obviously improve the compressive strength and the drop strength of green pellets, so that the normal production of the pellets can be ensured by adding a small amount of the composite additive, and the iron content of the pellets can be improved.
The invention adopts the following technical scheme:
the composite additive for the iron ore pellets comprises the following components in percentage by mass: 30-50% of tackifier, 10-20% of reinforcer, 5-10% of polyethylene glycol and the balance of water;
the tackifier is a mixture of xanthan gum and locust bean gum;
the enhancer is a mixture of guar gum and a boron-containing compound, and the boron-containing compound is sodium tetraborate and/or potassium tetraborate.
Preferably, in the tackifier, the mixing ratio of xanthan gum and locust bean gum is as follows: (20-80%): (80% to 20%).
Preferably, in the fortifier, the mixing ratio of the guar gum and the boron-containing compound is as follows: (20-40%): (80% to 60%).
Preferably, the xanthan gum is 20%, the locust bean gum is 20%, the guar gum is 10%, the sodium tetraborate is 20%, the polyethylene glycol is 10%, and the balance is water.
The invention also provides iron ore pellets, which comprise the iron-containing raw materials and the composite additive, wherein 1-5 kg of the composite additive is added in each ton of the iron-containing raw materials.
Preferably, the particle size of the iron ore pellet green pellets is 10.0-12.5 mm.
Preferably, the falling strength of the iron ore pellet green pellets is 5.6-8.6 times/0.5 m; the falling strength measurement process comprises the following steps: the green pellets were dropped freely on a steel plate having a height of 0.5m and a thickness of 10mm, and if they were cracked n times, the drop strength of the green pellets was (n-1) times/0.5 m.
Preferably, the compressive strength of the iron ore pellet green pellets is 12.4-17.4N/pellet; the determination process of the compressive strength comprises the following steps: placing the green ball on a balance, slowly applying a vertical downward pressure on the upper part of the green ball until the green ball is broken, wherein the pressure value displayed by the balance is the compressive strength of the green ball.
Compared with the prior art, the invention has the following beneficial effects:
the composite additive for iron ore pellets comprises the components of a tackifier, a reinforcer, polyethylene glycol and water, wherein the polyethylene glycol is used as a dispersing agent and can effectively disperse the tackifier added in raw materials, so that the tackifier is uniformly distributed in iron ore powder; the viscosity increaser is a mixture of xanthan gum and locust bean gum, the xanthan gum and the locust bean gum have very obvious synergistic thickening property and synergistic gelling property, and the thickening agent and the gelling agent are ideal thickening agents and gelling agents, can effectively bond mineral powder in the pelletizing process, and can increase pellet elasticity and improve the falling strength and compressive strength of green pellets. Guar gum and sodium tetraborate or potassium tetraborate in the reinforcer are crosslinked to generate gel, so that the falling strength of green pellets can be further improved. From the foregoing, it can be seen that the composite additive of the present invention can improve compressive strength and drop strength of green pellets, and therefore can reduce the return rate of iron ore pellets and can be used in place of bentonite.
Further, in the tackifier, the mixing ratio of xanthan gum and locust bean gum is as follows: (20-80%): (80% -20%), when xanthan gum and locust bean gum are mixed according to the proportion, the synergistic effect is very high. Particularly, when the mixing ratio of the xanthan gum to the locust bean gum is 8:2, the synergistic effect is best, and when the concentration of the mixed solution reaches 1%, the viscosity of the mixed solution of the xanthan gum and the locust bean gum is about 150 times that of the single solution of the locust bean gum and about 3 times that of the single solution of the xanthan gum. Therefore, the falling strength of the green pellets can be more effectively improved by mixing the green pellets and the water according to the proportion.
Further, in the enhancer, the mixing ratio of the guar gum and the boron-containing compound is as follows: (20-40%): (80% -60%), wherein the proportion of the boron-containing compound in the reinforcing agent is high, guar gum is combined with a small amount of the boron-containing compound to generate a crosslinking effect, the falling strength and the compressive strength of green pellets are effectively improved, and the green pellet quality is improved.
In the iron ore pellets, 1-5 kg of the composite additive is added into each ton of iron-containing raw materials, and compared with the prior art, the additive is less in addition amount, which is obviously lower than the average content of 3-5% of bentonite added into the pellets in the prior art, so that the total iron grade is not reduced compared with the bentonite, and the economic benefit is obvious. Meanwhile, by adding the composite additive, the plasticity of the mineral powder is improved, the pelletizing performance is improved, the wet strength of the pellet is improved, and the ore return rate is greatly reduced.
Detailed Description
The invention is further illustrated by the following examples:
the composite additive for iron ore pellets is prepared by mixing 30-50% of tackifier, 10-20% of enhancer, 5-10% of polyethylene glycol and water according to mass percentage. The tackifier is prepared from xanthan gum and locust bean gum (20-80%): (80% -20%) in proportion; the reinforcer is prepared from guar gum and boron-containing compound (20-40%): (80% -60%) of the above-mentioned raw materials.
Test conditions
(1) The pelletizing test method comprises the following steps: the green pellets are prepared by a disc pelletizer. The diameter of the pelletizer is phi 1000mm, the rotating speed of the disc is 20r/min, and the inclination angle is 45 degrees. The raw materials are uniformly mixed according to the proportion (the percentages are mass percentages) in the table 1, the mixture used for pelletizing is 5 kg, and after a proper amount of water is added before pelletizing, the mixture is manually and uniformly mixed and then added into a disc pelletizer for pelletizing. In the pelletizing process, a proper amount of atomized water is added, and the pelletizing time is 12 min. And after pelletizing, sieving the green pellets, and taking the green pellets with the diameter of 10.0-12.5 mm as qualified green pellets. The compressive strength and the drop strength were measured, and the measurement results are shown in table 2.
(2) The green ball falling strength measuring method comprises the following steps: the green ball was dropped freely on a steel plate having a height of 0.5m and a thickness of 10mm, and if the ball was broken after dropping n times, the dropping strength of the ball was (n-1) times/0.5 m. 10 green balls were measured each time, and the average was taken as the falling strength of the green balls (unit: times/0.5 m).
(3) The green ball compressive strength determination method comprises the following steps: placing the green ball on a balance, slowly applying a vertical downward pressure on the green ball until the green ball is broken, wherein the pressure value displayed by the balance is the compressive strength of the green ball. 10 green balls were measured each time, and the average value was taken as the compressive strength (unit: N/ball) of the green balls.
Test protocol
TABLE 1
TABLE 2
| Test number | Compressive strength (N/pieces) | Falling strength (times/0.5 m) |
| Control group | 10.1 | 3.2 |
| Example 1 | 12.4 | 5.6 |
| Example 2 | 14.7 | 7.1 |
| Example 3 | 17.4 | 8.6 |
As can be seen from Table 2, the green pellets obtained in examples 1 to 3 of the present invention were significantly improved in quality and both the drop strength and the compressive strength were significantly improved as compared with the control group. In example 3, compared with the control group, the falling strength of the green pellets is improved by 5.4 times/0.5 m, and the compressive strength is improved by 7.3N/green pellet.
Claims (2)
1. The composite additive for iron ore pellets is characterized by comprising the following components in percentage by mass: 30-50% of a tackifier, 10-20% of an enhancer, 5-10% of polyethylene glycol and the balance of water;
the tackifier is a mixture of xanthan gum and locust bean gum;
the enhancer is a mixture of guar gum and a boron-containing compound, and the boron-containing compound is sodium tetraborate and/or potassium tetraborate;
In the tackifier, the mixing ratio of xanthan gum and locust bean gum is as follows: 80%: 20 percent;
in the enhancer, the mixing ratio of the guar gum and the boron-containing compound is as follows: (20-40%): (80% ~ 60%).
2. The iron ore pellets are characterized by comprising iron-containing raw materials and the composite additive disclosed by claim 1, wherein 1-5 kg of the composite additive is added in each ton of the iron-containing raw materials;
the particle size of the iron ore pellet green pellets is 10.0-12.5 mm;
the falling strength of the iron ore pellet green pellets is 5.6-8.6 times/0.5 m;
the compressive strength of the iron ore pellet green pellets is 12.4-17.4N/pellet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010993394.0A CN112143885B (en) | 2020-09-21 | 2020-09-21 | Composite additive for iron ore pellets and iron ore pellets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010993394.0A CN112143885B (en) | 2020-09-21 | 2020-09-21 | Composite additive for iron ore pellets and iron ore pellets |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112143885A CN112143885A (en) | 2020-12-29 |
| CN112143885B true CN112143885B (en) | 2022-07-29 |
Family
ID=73893421
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010993394.0A Active CN112143885B (en) | 2020-09-21 | 2020-09-21 | Composite additive for iron ore pellets and iron ore pellets |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112143885B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2062145A1 (en) * | 1992-03-02 | 1993-09-03 | Cerminco Inc. | Self-fluxing binder composition for use in the pelletization of ore concentrates |
| CN1035481C (en) * | 1994-06-30 | 1997-07-23 | 潘金海 | Organic binder for metallurgy |
| CA2499146A1 (en) * | 2002-09-18 | 2004-04-15 | Akzo Nobel Nv | Binder composition and process for agglomerating particulate material |
| CN1851014A (en) * | 2006-05-29 | 2006-10-25 | 刘虎生 | Ironmaking oxidized pellet additive |
| CN103937969B (en) * | 2014-04-14 | 2016-01-20 | 辽宁科技大学 | A kind of powdered iron ore pellet binder and application thereof |
| CN105755280B (en) * | 2016-04-11 | 2018-02-16 | 东北大学 | A kind of iron ore pellets compound binding agent and its preparation and application |
-
2020
- 2020-09-21 CN CN202010993394.0A patent/CN112143885B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112143885A (en) | 2020-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101985689B (en) | Composite binder for iron ore pellets and preparation method thereof | |
| CN100562589C (en) | A kind of iron ore pellets sodium bentonite based binder and preparation method thereof | |
| CN101880766B (en) | Compound type binder used for pellet | |
| CN105567953A (en) | Iron-containing organic metallurgical pellet binder and preparation method thereof | |
| CN101654737B (en) | Compound iron ore pellet of molybdenum tailings and sulfate slags and preparation method thereof | |
| CN103937969A (en) | Iron ore powder pellet adhesive and application thereof | |
| CN104988308B (en) | Iron ore pellets richness iron compound binding agent and preparation method and purposes | |
| CN101921911A (en) | Pellet binder and preparation method thereof | |
| CN103468944B (en) | A kind of pelletizing binding agent and production method thereof | |
| CN112143885B (en) | Composite additive for iron ore pellets and iron ore pellets | |
| CN102121065B (en) | Mineral powder moulding binder | |
| CN110205487B (en) | Production method of fluorine-containing vanadium-titanium pellet ore | |
| CN113735631A (en) | Production method of low-energy-consumption potassium-calcium-magnesium-phosphate fertilizer | |
| CN112359204A (en) | Cold-pressed pellet adhesive, cold-pressed pellet and preparation method of cold-pressed pellet | |
| CN102936652A (en) | Preparation technique of iron ore pellets | |
| CN108796216B (en) | Pellet iron-magnesium composite binder and preparation and use methods thereof | |
| CN103146914A (en) | Cold-pressed high-strength fluorite pellet binder and use method thereof | |
| CN107365908A (en) | A kind of magnesia compound binding agent of pellet and preparation method thereof and application method | |
| CN104232888A (en) | Method for preparing cooled agglomerated pellets by using dry method electric fly ash of converter gas | |
| CN114214512B (en) | Pellet binder and preparation method and application thereof | |
| CN112195339A (en) | Contains K2O、Na2O, F pellet prepared by using magnetite concentrate as main material and combining with hematite concentrate and preparation method thereof | |
| CN112159238A (en) | Magnetic roasting iron-selecting tailing ceramsite and preparation method thereof | |
| CN102517444B (en) | Liquid state binder capable of reinforcing iron ore sintering, its preparation and its application method | |
| CN104975171A (en) | Boric sludge pellet binder/iron smelting auxiliary and preparation method of boric sludge pellet binder/iron smelting auxiliary | |
| CN112553460B (en) | Composite binder for improving pelletizing performance of super iron concentrate powder and using method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |