CN102994757A - Method for preparing ferro-silico-aluminum alloy by using Bayer process red mud - Google Patents
Method for preparing ferro-silico-aluminum alloy by using Bayer process red mud Download PDFInfo
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- CN102994757A CN102994757A CN2012104945152A CN201210494515A CN102994757A CN 102994757 A CN102994757 A CN 102994757A CN 2012104945152 A CN2012104945152 A CN 2012104945152A CN 201210494515 A CN201210494515 A CN 201210494515A CN 102994757 A CN102994757 A CN 102994757A
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Abstract
The invention discloses a method for preparing a ferro-silico-aluminum alloy by using Bayer process red mud. The method comprises the following preparation steps of: (1) preparing acidity correction liquid, and subsequently adding the Bayer process red mud into the acidity correction liquid to be subjected to pretreatment; (2) filtering, washing and returning the filtrate to be prepared; (3) drying and crushing filter cakes, preparing and briquetting with a reducing agent, a binder and water, shaping and drying; and (4) adding the dried pellets into high-temperature smelting equipment to be smelted so as to obtain the pure ferro-silico-aluminum alloy. By utilizing the method, the production process of the ferro-silico-aluminum alloy is shortened, the industry chain is prolonged, and the acid lixivium can be recycled, so that the production cost of the ferro-silico-aluminum alloy is greatly reduced. Process parameters are easy to control; and the effective utilization rates of three elements, namely, sodium, silicon and aluminum, are more than 99%. Non-waste emission of a system is realized, the environment pollution is reduced, and more connection between the aluminum oxide industry and the alloy industry is realized with constant working, so that the method facilitates large-scale industrial production.
Description
Technical field
The invention belongs to the metallurgical engineering field, relate to the method that a kind of Bayer process red mud prepares Alsimin.
Background technology
The key that alkaline process is produced aluminum oxide is that aluminium separates with silicon, and in the process of Bayer process high pressure digestion diaspore, nearly all silicon mine all is active at home, mostly will and mainly enter red mud with the Bayer process red mud form with the sodium aluminate solution reaction; In the process for desiliconizing crude liquid obtained by sinter process, the SiO more than 90%
2Also separate out from solution with the form of Bayer process red mud.Contain a large amount of alkali and aluminum oxide in the Bayer process red mud, and the quantity of slag (when the medium grade ore of Bayer process high pressure digestion ore deposit and in the process for desiliconizing crude liquid obtained by sinter process, approximately reaches respectively 1000kg/t-Al greatly in producing
2O
3And 200kg/t-A1
2O
3).
Chinese patent 200410023916.5 has been introduced the method for utilizing Bayer process red mud to produce the 4A zeolite, this technological process is: first Bayer process red mud is carried out purifying treatment, then prepare burden by a certain percentage with ground caustic, enter the High Temperature Furnaces Heating Apparatus sintering, to be placed on stripping in the alkaline solution after the pulverizing of the grog behind the sintering, then dissolution fluid is carried out crystallization, aging processing, reach the 4A zeolite product.This technique also can reach the purpose that turns waste into wealth, can reduce alumina producing consumption equally, but the shortcoming of this technique is the process that needs process high temperature to burn till, also increased cost in the time of to the recycling Bayer process red mud, be exactly to reduce DeGrain on the cost, it is not high in the efficient recovery rate of silicon, aluminium and sodium that this technique also has a shortcoming, and a large amount of compositions have participated in producing the invalid circulation of large flow process again.Flow process is also long, and technique is loaded down with trivial details, cost is high.
Alsimin in the cast steel process first deoxidation and final deoxygenation can prevent from tapping and pour into a mould in secondary oxidation, and large nearly one times of density ratio fine aluminium density easily enters molten steel, inner scaling loss is few; Easily form the low melting point product, on float to the molten steel surface, reduce being mingled with in the steel part, cleaning molten steel is arranged and improves the positive effect of steel part toughness.Alsimin save silicomanganese 10%, and than great, penetration power is strong than low by 30% with the fine aluminium price, and is easily affine with molten steel, and the fragmentation effect of minimizing aluminium in molten steel is further enhanced the intensity of steel part and performance.
Nearly 500,000,000 tons of the every annual output steel of China, rolling shapes are more and more, approximately need 500,000 tons of aluminium silicon every year.At present, 80% Alsimin needs import, not only consumes a large amount of foreign exchanges, and seriously is limited by the world market.Alsimin is as steel making deoxidant, and market is larger, and prospect is very good.
Alsimin also can be made the reductive agent of non-ferrous metal, and such as smelting magnesium, calcium etc., under the overall background that MAGNESIUM METAL, calcium smelting industry heat up gradually, the application quantity of Alsimin is with increasing.
The distinctive metal properties of Alsimin is by the cognition of increasing field institute, automotive industry, space flight and aviation is industrial and numerous industries such as all kinds of mechanical industries on all Alsimin is used as novel material.The multicomponent alloy that Alsimin and other metals form also is found gradually and promotes, the aluminium silicon titanium alloy that forms as in Alsimin, adding an amount of titanium, and its physical strength, erosion resistance and thermostability are more excellent.
At present the sial produced of China all is to adopt the method for mixing, namely take metallic aluminium and silicon as raw material, forms mixing after the fusing respectively, though this method technique is simple, and owing to adopting fine aluminium and silicon price higher, metallic aluminium particularly.Thereby the Alsimin of producing with direct method, namely electrothermal reduction makes Alsimin, because its operation is few, cost is low and quality good, has the larger market competitiveness.After putting on market, will inevitably progressively replace the Alsimin of producing mixing method, and become the leading product in market.
From deoxidation effect and Financial cost contrast, Alsimin is best steel-making end-deoxidizer at present, has now formed the deoxidation system with Alsimin+silicocalcium+other alloy.
Summary of the invention
The object of the present invention is to provide a kind of Bayer process red mud to prepare the method for Alsimin, adopt renewable energy resources Bayer process red mud to produce Alsimin, reduce cost on the raw material, effectively utilize waste residue and waste material, promote the throughput of alumina industry, greatly reduce the production cost of Alsimin.
Bayer process red mud of the present invention prepares the method for Alsimin, and preparation process is as follows:
(1) then the acid liquid of adjusting of configuration add Bayer process red mud the acid liquid of adjusting and carry out pre-treatment;
(2) filter, the washing rear filtrate returns batching;
(3) after the filter cake oven dry fragmentation, with reductive agent, binding agent and water batching and briquetting, after the moulding, oven dry;
(4) the oven dry pelletizing joins and carries out melting in the high temperature smelting equipment and obtain pure Alsimin.
Wherein,
Step (1) souring soln is that hydrochloric acid, distilled water and filtrate mixing preparation form, wherein, and H in the acid adjustment liquid
+Concentration is 0.02-0.3mol/L.
The liquid-solid ratio of step (1) preprocessing solution is 3-15, and souring temperature is 20-40 ℃, and acidificatoin time is 0.5-1.5 hour.
After filtrate proportion reaches 1.3, can get to chlor-alkali plant and reclaim as salts solution, chlor-alkali plant is produced hydrochloric acid and liquid caustic soda, and hydrochloric acid returns the acid liquid of adjusting of preparation, and liquid caustic soda is as the aluminum oxide flow process.
Step (2) washings is distilled water, and the washing liquid-solid ratio is 3-8, and wash temperature is 70-90 ℃.
After filter cake is dried fragmentation in the step (3), granularity d50=40-80um; Oven dry pelletizing diameter is 2-6mm.
In the step (3), the reductive agent add-on is the 50-65% of Bayer process red mud total mass, and the binding agent add-on is the 3-7% of Bayer process red mud total mass, and the water add-on is Bayer process red mud total mass 5-10%.
Step (3) binding agent is powdery sodium silicate, granularity d50=10-30um.Wherein, silicon oxide is the 30-50% of binding agent total mass, modulus M=2.3-3.2.
Reductive agent is bituminous coal in the step (3), volatile matter〉28%; 60% bituminous coal d50=10-80um, 40% bituminous coal granularity d50=1-3mm.
The pelletizing bake out temperature is 100-200 ℃ in the step (4), and moisture is＜1.5% after the oven dry.
High temperature smelting equipment is electric arc furnace or mineral hot furnace in the step (4), and sintering atmosphere is reducing atmosphere.
The present invention compared with prior art has following beneficial effect:
(1) no longer adopt aluminium element silicon melting operation to obtain, but utilize the effective silane agent in the desiliconization waste residue to synthesize, and shortened the Alsimin Production Flow Chart, extended industrial chain, and acid leaching solution can recycle, greatly reduces the production cost of Alsimin.
(2) processing parameter is easily controlled, and sodium, silicon and aluminium element effective rate of utilization can reach more than 99%.
(3) select separately the hydrochloric acid filtering solution that contains sodium-chlor to allocate, realized system without trash discharge.
(4) application of the present invention is conducive to reduce because of Bayer process red mud and sneaks into red mud to the pollution of environment.
(5) realize another interface of alumina industry and alloy industry, realized continuous operations, be convenient to carry out large industrialized production.
(6) the Alsimin market capacity is large, and the application of technology is strong.
Embodiment:
The invention will be further described below in conjunction with embodiment.
Embodiment 1
Utilize Bayer process red mud to produce in the Alsimin, Bayer process red mud material composition per-cent is Al
2O
3: 10%, Fe
2O
3: 48%, SiO
2: 14%, CaO:4%, Na
2O:8%, TiO
2: 6%, igloss: 10%; The bituminous coal carbon content is 50%.
Step is as follows:
(1) hydrochloric acid (31%), distilled water and filtrate mixing preparation are become H
+Concentration is the acid liquid of adjusting of 0.05mol/L.The 1000kg Bayer process red mud is added the acid liquid of adjusting carry out pre-treatment.Acidulated condition is: 40 ℃ of souring temperatures, acidificatoin time are 1.1 hours, and liquid-solid ratio is 9.
(2) infusion solution is filtered, filtrate is returned batching, then uses 90 ℃ of distilled water to filter cake washing, obtains filter cake 708kg.
Wherein, the washing liquid-solid ratio is 3, and filtrate proportion reaches 1.3 when above, gets to chlor-alkali plant and reclaims, chlor-alkali plant production hydrochloric acid and liquid caustic soda.
(3) after the filter cake oven dry fragmentation, control granularity d50 is 40um.Then prepare burden and briquetting with 3% powdery sodium silicate of Bayer process red mud total mass, 50% bituminous coal and Bayer process red mud total mass 5% water of Bayer process red mud total mass, after the moulding, 150 ℃ of oven dry, moisture reaches 1.4%.Moulding pelletizing diameter is 2mm.
Wherein, binding agent powdery sodium silicate, granularity d50 are 10um, and silica content is 50% of binding agent total mass, modulus M=3.2; The bituminous coal control granularity d50=10um of the volatile matter 28.5%, 60% of reductive agent bituminous coal, 40% bituminous coal granularity d50=3mm;
(4) join in the electric arc furnace, the control reducing atmosphere obtains Alsimin 393kg.
Embodiment 2
Utilize Bayer process red mud to produce in the Alsimin, Bayer process red mud material composition per-cent is Al
2O
3: 15%, Fe
2O
3: 40%, SiO
2: 13%, CaO:3%, Na
2O:7%, TiO
2: 5%, igloss: 15%; The bituminous coal carbon content is 60%.
Step is as follows:
(1) hydrochloric acid (31%), distilled water and filtrate mixing preparation are become H
+Concentration is the acid liquid of adjusting of 0.3mol/L.The 1000kg Bayer process red mud is added the acid liquid of adjusting carry out pre-treatment.Acidulated condition is: liquid-solid ratio is 3, and 20 ℃ of souring temperatures, acidificatoin time are 1.5 hours.
(2) infusion solution is filtered, filtrate is returned batching, then uses 70 ℃ of distilled water to filter cake washing, obtains filter cake 708kg.
Wherein, the washing liquid-solid ratio is 8, and filtrate proportion reaches 1.3 when above, gets to chlor-alkali plant and reclaims, and chlor-alkali plant is produced hydrochloric acid and liquid caustic soda.
(3) after the filter cake oven dry fragmentation, control granularity d50 is 80um.Then prepare burden and briquetting with 7% powdery sodium silicate, 65% bituminous coal of Bayer process red mud total mass and the water of Bayer process red mud total mass 10% of Bayer process red mud total mass, after the moulding, 200 ℃ of oven dry, moisture reaches 1.2%.Moulding pelletizing diameter is 6mm.
Wherein, binding agent powdery sodium silicate, granularity d50 are 30um, and silica content is 30% of binding agent total mass, modulus M=2.3; The bituminous coal control granularity d50=80um of the volatile matter 28.5%, 60% of reductive agent bituminous coal, 40% bituminous coal granularity d50=1mm;
(4) add in the mineral hot furnace, the control reducing atmosphere obtains Alsimin 402kg.
Embodiment 3
Utilize Bayer process red mud to produce in the Alsimin, Bayer process red mud material composition per-cent is Al
2O
3: 20%, Fe
2O
3: 38%, SiO
2: 12%, CaO:4%, Na
2O:9%, TiO
2: 4%, igloss: 8%; The bituminous coal carbon content is 55%.
Step is as follows:
(1) hydrochloric acid (31%), distilled water and filtrate mixing preparation are become H
+Concentration is the acid liquid of adjusting of 0.1mol/L.The 1000kg Bayer process red mud is added the acid liquid of adjusting carry out pre-treatment.Acidulated condition is: 30 ℃ of temperature, and the time is 0.5 hour, liquid-solid ratio is 13.
(2) infusion solution is filtered, filtrate is returned batching, then uses 80 ℃ of distilled water to filter cake washing, obtains filter cake 708kg.
Wherein, the washing liquid-solid ratio is 6, and filtrate proportion reaches 1.3 when above, gets to chlor-alkali plant and reclaims, chlor-alkali plant production hydrochloric acid and liquid caustic soda.
(3) after the filter cake oven dry fragmentation, control granularity d50 is 60um.Then prepare burden and briquetting with 5% powdery sodium silicate of Bayer process red mud total mass, 58% bituminous coal and Bayer process red mud total mass 6% water of Bayer process red mud total mass, after the moulding, 180 ℃ of oven dry, moisture is 1.1%.Moulding pelletizing diameter is 4mm.
Wherein, binding agent powdery sodium silicate, granularity d50 are 20um, and silica content is 40% of binding agent total mass, modulus M=2.8; The bituminous coal control granularity d50=40um of the volatile matter 28.5%, 60% of reductive agent bituminous coal, 40% bituminous coal granularity d50=2mm;
(4) add in the mineral hot furnace, the control reducing atmosphere obtains Alsimin 397kg.
Claims (10)
1. a Bayer process red mud prepares the method for Alsimin, it is characterized in that, step is as follows:
(1) then the acid liquid of adjusting of configuration add Bayer process red mud the acid liquid of adjusting and carry out pre-treatment;
(2) filter, the washing rear filtrate returns batching;
(3) after the filter cake oven dry fragmentation, with reductive agent, binding agent and water batching and briquetting, after the moulding, oven dry;
(4) the oven dry pelletizing joins and carries out melting in the high temperature smelting equipment and obtain pure Alsimin.
2. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, acid adjustment liquid is that hydrochloric acid, distilled water and filtrate mixing preparation form in the step (1); Wherein, H in the acid adjustment liquid
+Concentration is 0.02-0.3mol/L.
3. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, the liquid-solid ratio of preprocessing solution is 3-15 in the step (1), and souring temperature is 20-40 ℃, and acidificatoin time is 0.5-1.5 hour.
4. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, step (2) washings is distilled water, and the washing liquid-solid ratio is 3-8, and wash temperature is 70-90 ℃.
5. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, and after filter cake is dried fragmentation in the step (3), d50=40-80um; Oven dry pelletizing diameter is 2-6mm.
6. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, the reductive agent add-on is the 50-65% of Bayer process red mud total mass in the step (3), and the binding agent add-on is the 3-7% of Bayer process red mud total mass, and water is Bayer process red mud total mass 5-10%.
According to claim 1 or 6 described Bayer process red muds prepare the method for Alsimin, it is characterized in that, step (3) binding agent is powdery sodium silicate, granularity d50=10-30um; Wherein, silicon oxide is the 30-50% of binding agent total mass, modulus M=2.3-3.2.
According to claim 1 or 6 described Bayer process red muds prepare the method for Alsimin, it is characterized in that, reductive agent is bituminous coal in the step (3), volatile matter〉28%; 60% bituminous coal granularity d50=10-80um, 40% bituminous coal granularity d50=1-3mm.
9. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, the pelletizing bake out temperature is 100-200 ℃ in the step (4), and moisture is＜1.5% after the oven dry.
10. Bayer process red mud according to claim 1 prepares the method for Alsimin, it is characterized in that, high temperature smelting equipment is electric arc furnace or mineral hot furnace in the step (4), and sintering atmosphere is reducing atmosphere.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103602805A (en) * | 2013-12-10 | 2014-02-26 | 中国铝业股份有限公司 | Red mud pellets and preparation method thereof |
| CN103866128A (en) * | 2014-03-10 | 2014-06-18 | 北京科技大学 | Method of directly producing aluminum iron alloy by using carbothermy reduced aluminium metallurgy red mud |
| CN106148683A (en) * | 2016-08-01 | 2016-11-23 | 江苏省冶金设计院有限公司 | Prepare the method and system of red mud pelletizing |
| CN106435411A (en) * | 2016-10-24 | 2017-02-22 | 马鞍山顺发机械制造有限公司 | Thermal fatigue-resistant casting material for heavy-duty truck engine |
| CN111647741A (en) * | 2020-06-12 | 2020-09-11 | 山东煜龙环保科技股份有限公司 | Method for producing ferro-silico-aluminum alloy by using red mud iron powder |
| CN114787397A (en) * | 2019-11-25 | 2022-07-22 | 力拓加铝国际有限公司 | Method and apparatus for purifying bayer process streams |
-
2012
- 2012-11-27 CN CN2012104945152A patent/CN102994757A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103602805A (en) * | 2013-12-10 | 2014-02-26 | 中国铝业股份有限公司 | Red mud pellets and preparation method thereof |
| CN103602805B (en) * | 2013-12-10 | 2016-01-13 | 中国铝业股份有限公司 | A kind of red mud pelletizing and preparation method thereof |
| CN103866128A (en) * | 2014-03-10 | 2014-06-18 | 北京科技大学 | Method of directly producing aluminum iron alloy by using carbothermy reduced aluminium metallurgy red mud |
| CN103866128B (en) * | 2014-03-10 | 2016-01-20 | 北京科技大学 | Carbothermy reduction aluminium metallurgy red mud direct production ferroaluminium |
| CN106148683A (en) * | 2016-08-01 | 2016-11-23 | 江苏省冶金设计院有限公司 | Prepare the method and system of red mud pelletizing |
| CN106148683B (en) * | 2016-08-01 | 2018-07-10 | 江苏省冶金设计院有限公司 | Prepare the method and system of red mud pelletizing |
| CN106435411A (en) * | 2016-10-24 | 2017-02-22 | 马鞍山顺发机械制造有限公司 | Thermal fatigue-resistant casting material for heavy-duty truck engine |
| CN114787397A (en) * | 2019-11-25 | 2022-07-22 | 力拓加铝国际有限公司 | Method and apparatus for purifying bayer process streams |
| CN111647741A (en) * | 2020-06-12 | 2020-09-11 | 山东煜龙环保科技股份有限公司 | Method for producing ferro-silico-aluminum alloy by using red mud iron powder |
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Application publication date: 20130327 |