CN102925611B - Method for modifying iron ore powder by composite additive to prevent sticking and defluidizing during fluidization reduction - Google Patents
Method for modifying iron ore powder by composite additive to prevent sticking and defluidizing during fluidization reduction Download PDFInfo
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- CN102925611B CN102925611B CN201210408492.9A CN201210408492A CN102925611B CN 102925611 B CN102925611 B CN 102925611B CN 201210408492 A CN201210408492 A CN 201210408492A CN 102925611 B CN102925611 B CN 102925611B
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Abstract
The invention relates to a method for modifying iron ore powder by utilizing a composite additive to prevent sticking and defluidizing during fluidization reduction. The method comprises the following steps of: modifying the iron ore powder before a fluidization reduction process step, firstly preparing a 0.5%-60% additive solution, then dipping the iron ore powder in the additive solution, adsorbing the additive onto the surface of the iron ore powder or a pore canal by utilizing the adsorption performance of the iron ore powder, and performing fluidization preheating treatment on the modified iron ore powder. According to the method disclosed by the invention, the occurrence of sticking and defluidizing during the fluidization reduction can be effectively inhibited, and the reduction degree and the metallization rate are respectively improved by 45%-55% and 30%-40%. Simultaneously, the additive can realize cyclic utilization by magnetic separation so as to ensure product quality. The method disclosed by the invention has the advantages of a wide range of applications of ore, and capability of adjusting the composition of the composite additive against the characteristics of the type of the iron ore powder to achieve the best anti-sticking effect; and simultaneously, the process flow of the fluidization reduction process is not changed, and the method is simple to operate and economic and practical.
Description
Technical field
The invention belongs to ironmaking production technical field, be specifically related to a kind of composite additive Modified Iron breeze and prevent fluidized reduction process bonding defluidization and the method that improves degree of metalization.
Background technology
At present, externally degree of complying with is in 60% left and right for China's iron ore deposit, and iron ore deposit supply becomes bottleneck problem.Along with high grade iron ore resources is in the world increasingly exhausted, natural rich ore, lump ore are fewer and feweri, and therefore, China will solve iron ore deposit shortage problem, must be based on the utilization of low-grade, compound mineral intergrowth resource.Particularly China's iron ore deposit grade is low, reach ironmaking grade requirement, need produce fine iron fine powder through fine grinding, beneficiation enrichment, and along with the minimizing of iron ore deposit with will obtain high elimination factor and iron grade, the granularity of iron fine powder will be more and more less.Fine ore or iron fine powder be through sintering for agglumeration traditionally, enters blast furnace ironmaking after improving physical property again, and that sintering for agglumeration not only consumes energy is high, it is heavy to pollute, and compared with large fine ore specific surface area because sintering for agglumeration significantly reduces, be irrational from kinetics of reduction.Gas-solid contact has been strengthened in fluidized bed gas ironmaking, can effectively utilize the feature that fine ore specific surface area is large, thereby shortens the recovery time, is to solve the effective technology that powder utilizes.
But from production angle, the main difficulty of fluidized reduction technology practical application be powdered iron ore in high temperature fluidized reduction process, particle bonding is agglomerating or adhere to wall, affects normally carrying out of fluidisation.For maintaining operation, have to adopt low temperature (600 ° of C～700 ° C, generally not higher than 850 ° of C), high gas speed, low reduction ratio conditional operation, not only reduction rate and production efficiency are little, gas effciency is low, and very easily facilitate the carbon of analysing of CO to react, consequently cause the overall energy consumption of technique to increase.Although can avoid bonding 570 ° of reduction below C, at this temperature, H
2can reduce Fe
2o
3for Fe, CO also principle is very difficult.For fluidization direct-reduced iron, owing to requiring, reduction of iron ore fines degree is higher, and the defluidization problem that therefore bonds is more outstanding.Solve bonding defluidization problem and be the key that can fluidization ironmaking equipment steady running.
Many scholars conduct in-depth research for the defluidization that bonds in fluidized reduction process.Zhu Kaisun etc. (Huadong Metallurgy College journal, 1989,1078-1087) propose to take low temperature to analyse the method for carbon, prevent bonding by the coated powdered iron ore particle of attached carbon (1%～2%), have improved reduction efficiency simultaneously.Hayashi etc. (ISIJ Int., 1993,1078-1087) find with containing gangue content (Al
2o
3, MgO, CaO) the coated powdered iron ore of grout can effectively suppress the generation of bonding.Wang Jianjuns etc. (CN101624639A) find that granularity is less than to the additive coke powder of 1mm or limestone powder or ground dolomite evenly mixes with powdered iron ore with the ratio of powdered iron ore mass ratio 2～8%, powdered iron ore fluid effect obviously improves, and degree of metalization improves 12～21%.(CN 102296139A) the powdered iron ore surface sprinkling such as Guo Zhancheng or flood certain density Mg (NO
3)
2solution, after fluid bed reduction tail gas is dry, then enters fluid bed reduction reaction, fluidizing performance be improved significantly, degree of metalization reaches 90%.Therefore, what how to suppress to bond defluidization in fluidized reduction process is the key that improves reduction efficiency and quality product, and it,, for promoting new and effective ironmaking technology, saves production cost, and protection of the environment is significant.
Summary of the invention
The technology of the present invention is dealt with problems: cause that for phenomenons such as powdered iron ore fluidized reduction process breeze bonding, defluidizations reduction process cannot continuity operate, degree of metalization lowly cannot reach the technical problem of hot wafering requirement, provide a kind of additive agent modified powdered iron ore to prevent the method for fluidized reduction process bonding defluidization, the method can reduce the generation of bonding defluidization, improve reduction efficiency and resultant metal rate simultaneously, reach the object that high efficiency continuously is produced.
The technology of the present invention solution: a kind of method of utilizing composite additive Modified Iron breeze to prevent fluidized reduction process bonding defluidization, performing step is as follows:
(1) be Ca (NO by additive
3)
2, Al (NO
3)
3, Mg (NO
3)
2in any two or three composite combined be added to the water and be mixed with binder component to account for total concn be 0.5%～60% additive solution;
(2) stir with the speed of 10r/min～60r/min, stir in additive solution process and add simultaneously and be less than 70 object powdered iron ore, the mass ratio of powdered iron ore and additive solution is 0.1:10～10:1;
(3) dipping time of powdered iron ore in additive solution is 20min～60min, utilize the absorption property of powdered iron ore that additive is loaded in particle surface or duct, then powdered iron ore directly or after filtering is dried from additive solution under 25 ° of C～300 ° C;
(4) dried powdered iron ore is carried out to two-part fluidized reduction: first paragraph is roasting and prereduction, dried powdered iron ore is placed in to fluidized-bed and under 300 ° of C～900 ° C, carries out fluosolids roasting and prereduction; Second segment is reduction eventually, and going back eventually original product is sponge iron;
(5) last, the product of reduction is isolated the sponge iron of high degree of metalization (60%～80%) and the slag phase containing additive by magnetic separation eventually.
After described step (5), slag is made to additive solution mutually again, realize recycle and reuse.
The total concn of the binder component in described step (1) is 2%～40%.
Described step stirs with the speed of 20r/min～40r/min in (2).
In described step (3), powdered iron ore directly or after filtering is dried from additive solution under 60 ° of C～120 ° C.
Additive in described step (1) is two kinds of component compound tenses, and each constituent mass percentage ratio is 10%～70%; Be three kinds of component compound tenses for additive, each constituent mass mark is 10%～70%.
In described step (4), dried powdered iron ore is placed in to fluidized-bed and carries out fluosolids roasting and prereduction under 600 ° of C～800 ° C.
In described step (4), whole reducing gas is H
2=10%～30%, CO=70%～90%, flow line speed is 0.3m/s～0.7m/s, temperature is 700 ° of C～1000 ° C.
The advantage of the present invention compared with existing fluidized-bed iron-smelting process technology is:
(1) powdered iron ore in the present invention, by the generation of the defluidization that both can suppress after additive agent modified to bond, can improve again reduction efficiency and the resultant metal rate of powdered iron ore.Simultaneously additive can pass through again magnetic separator recycle and reuse, on quality product without impact.
(2) composite additive in the present invention has wider suitability than single additive, can adjust additive composition for the species characteristics of different powdered iron ore, to reach best anti-adhesion effects.
(3) the present invention does not change any equipment and the flow process of existing fluidized-bed, has low, simple to operate, the economical and practical feature of investment.
Accompanying drawing explanation
Fig. 1 is the additive agent modified powdered iron ore two-part fluidized reduction process flow sheet of the present invention.
Embodiment
Introduce in detail the present invention below in conjunction with drawings and the specific embodiments.But following embodiment only limits to explain the present invention, and protection scope of the present invention should comprise the full content of claim, is not limited only to the present embodiment.
Method of the present invention is: before fluidized reduction operation, additive is added to the water and is mixed with the solution of binder component total concn as 0.5%～60% take the form of nitrate, in stirred solution process, add and be less than 70 object powdered iron ore, the mass ratio of powdered iron ore and additive solution is 0.1:10～10:1, utilize the absorption property of powdered iron ore that additive is loaded in particle surface or duct, then powdered iron ore directly or after filtering is dried from solution.The powdered iron ore obtaining is carried out to two-part fluidized reduction: first paragraph is roasting and prereduction, second segment is reduction eventually.Finally, go back original product and isolate the sponge iron of high degree of metalization and the slag phase containing additive by magnetic separation.Slag is made solution mutually again, realizes recycle and reuse.Present method can effectively suppress to bond in fluidized reduction process generation of defluidization, make reduction degree and degree of metalization improve respectively 45%～55% and 30%～40%, and can adjust for the species characteristics of different powdered iron ore the composition of composite additive, to reach best anti-adhesion effects, therefore there is the wider scope of application.
Embodiment 1
A kind of granularity is less than 70 object powdered iron ore, add composite additive nitrocalcite and aluminum nitrate (mass ratio 1:1), additive solution concentration is 20%, solution and powdered iron ore mass ratio are 3:1, after stirring, flood, drying, powdered iron ore after modification being placed in to fluidized-bed and carrying out fluosolids roasting and prereduction, is then 800 ° of C in fluid bed reduction temperature, and reducing gas is H
2=20%, CO=80%, flow line speed is under 0.5m/s condition, to carry out whole reduction.Normally fluidisation of prereduction and whole reduction process, fluidized-bed pressure differential maintain is constant, and fluidized state is normal, and degree of metalization can reach 73.70%, has improved 30.45% when additive-free.Slag after magnetic separation separates is through nitric acid dissolve, filtration, and being again mixed with concentration is 20% additive solution.
Embodiment 2
A kind of granularity is less than 70 object powdered iron ore, add composite additive nitrocalcite and aluminum nitrate (mass ratio 1:2), additive solution concentration is 40%, solution and powdered iron ore mass ratio are 3:1, after stirring, flood, drying, the powdered iron ore after modification is placed in to fluidized-bed and carries out fluosolids roasting and prereduction.Then be 900 ° of C in fluid bed reduction temperature, reducing gas is H
2=20%, CO=80%, flow line speed is under 0.5m/s condition, to carry out whole reduction.Normally fluidisation of prereduction and whole reduction process, fluidized-bed pressure differential maintain is constant, and fluidized state is normal, and degree of metalization can reach 82.54%, has improved 38.99% when additive-free.Slag after magnetic separation separates is through nitric acid dissolve, filtration, and being again mixed with concentration is 40% additive solution.
Embodiment 3
A kind of granularity is less than 70 object powdered iron ore, add composite additive magnesium nitrate and nitrocalcite (mass ratio 1:1), additive solution concentration is 20%, solution and powdered iron ore mass ratio are 3:1, after stirring, flood, drying, the powdered iron ore after modification is placed in to fluidized-bed and carries out fluosolids roasting and prereduction.Then be 800 ° of C in fluid bed reduction temperature, reducing gas is H
2=20%, CO=80%, flow line speed is under 0.5m/s condition, to carry out whole reduction.Normally fluidisation of prereduction and whole reduction process, fluidized-bed pressure differential maintain is constant, and fluidized state is normal, and degree of metalization can reach 78.43%, has improved 34.88% when additive-free.Slag after magnetic separation separates is through nitric acid dissolve, filtration, and being again mixed with concentration is 20% additive solution.
Embodiment 4
A kind of granularity is less than 70 object powdered iron ore, add composite additive magnesium nitrate and aluminum nitrate (mass ratio 1:1), additive solution concentration is 40%, solution and powdered iron ore mass ratio are 3:1, after stirring, flood, drying, the powdered iron ore after modification is placed in to fluidized-bed and carries out fluosolids roasting and prereduction.Then be 800 ° of C in fluid bed reduction temperature, reducing gas is H
2=20%, CO=80%, flow line speed is under 0.5m/s condition, to carry out whole reduction.Normally fluidisation of prereduction and whole reduction process, fluidized-bed pressure differential maintain is constant, and fluidized state is normal, and degree of metalization can reach 79.89%, has improved 36.34% when additive-free.Slag after magnetic separation separates is through nitric acid dissolve, filtration, and being again mixed with concentration is 40% additive solution.
Embodiment 5
A kind of granularity is less than 70 object powdered iron ore, add composite additive nitrocalcite, aluminum nitrate and magnesium nitrate (mass ratio 1:1:1), additive solution concentration is 20%, solution and powdered iron ore mass ratio are 2:1, after stirring, flood, drying, the powdered iron ore after modification is placed in to fluidized-bed and carries out fluosolids roasting and prereduction.Then be 900 ° of C in fluid bed reduction temperature, reducing gas is H
2=10%, CO=90%, flow line speed is under 0.5m/s condition, to carry out whole reduction.Normally fluidisation of prereduction and whole reduction process, fluidized-bed pressure differential maintain is constant, and fluidized state is normal, and degree of metalization can reach 84.25%, has improved 40.70% when additive-free.Slag after magnetic separation separates is through nitric acid dissolve, filtration, and being again mixed with concentration is 20% additive solution.
The impact (statistical average value) of table 1 different additive on reduction of iron ore fines effect
In a word, the present invention's can effectively suppress to bond in fluidized reduction process generation of defluidization, makes reduction degree and degree of metalization reach respectively 70%～90% and 60～80%, improves respectively 45%～55% and 30%～40% than prior art.Composite additive can be separated and be realized recycle by magnetic separation simultaneously, to guarantee quality product.The present invention be advantageous in that mineral are applied widely, the composition that can adjust composite additive for the species characteristics of powdered iron ore, to reach best anti-adhesion effects, does not change the technical process of fluidized reduction process simultaneously, simple to operate, economical and practical.
It should be noted that, according to the various embodiments described above of the present invention, those skilled in the art are the four corners that can realize independent claim of the present invention and appurtenance completely, implementation procedure and method same the various embodiments described above; And non-elaborated part of the present invention belongs to techniques well known.
The above; be only part embodiment of the present invention, but protection scope of the present invention is not limited to this, in the technical scope that any those skilled in the art disclose in the present invention; the variation that can expect easily or replacement, within all should being encompassed in protection scope of the present invention.
Claims (7)
1. utilize composite additive Modified Iron breeze to prevent a method for fluidized reduction process bonding defluidization, it is characterized in that performing step is as follows:
(1) be Ca (NO by additive
3)
2, Al (NO
3)
3, Mg (NO
3)
2in any two or three composite combined be added to the water that to be mixed with binder component total concn be 0.5%～60% additive solution; Described additive is two kinds of component compound tenses, and each constituent mass percentage ratio is 10%～70%; Be three kinds of component compound tenses for additive, each constituent mass mark is 10%～70%;
(2) stir with the speed of 10r/min～60r/min, stir in additive solution process and add simultaneously and be less than 70 object powdered iron ore, the mass ratio of powdered iron ore and additive solution is 0.1:10～10:1;
(3) dipping time of powdered iron ore in additive solution is 20min～60min, utilize the absorption property of powdered iron ore that additive is loaded in particle surface or duct, then powdered iron ore directly or after filtering is dried from additive solution at 25 ℃～300 ℃;
(4) dried powdered iron ore is carried out to two-part fluidized reduction: first paragraph is roasting and prereduction, dried powdered iron ore is placed in to fluidized-bed and at 300 ℃～900 ℃, carries out fluosolids roasting and prereduction; Second segment is reduction eventually, and going back eventually original product is sponge iron;
(5) last, the product of reduction separates the sponge iron of 60%～80% high degree of metalization and the slag phase containing additive by magnetic separation eventually.
2. method according to claim 1, is characterized in that: after described step (5), slag is made to additive solution mutually again, realize recycle and reuse.
3. method according to claim 1 and 2, is characterized in that: the total concn of the binder component in described step (1) is 2%～40%.
4. method according to claim 1 and 2, is characterized in that: described step stirs with the speed of 20r/min～40r/min in (2).
5. method according to claim 1 and 2, is characterized in that: in described step (3), powdered iron ore directly or after filtering is dried from additive solution at 60 ℃～120 ℃.
6. method according to claim 1 and 2, is characterized in that: in described step (4), dried powdered iron ore is placed in to fluidized-bed and carries out fluosolids roasting and prereduction at 600 ℃～800 ℃, prereduction gas is the tail gas reducing eventually.
7. method according to claim 1 and 2, is characterized in that: in described step (4), whole reducing gas is H
2=10%～30%, CO=70%～90%, flow line speed is 0.3m/s～0.7m/s, temperature is 700 ℃～1000 ℃.
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| CN106755684B (en) * | 2016-12-01 | 2019-11-05 | 华北理工大学 | A kind of method of iron ore fluidized reduction ironmaking |
| CN112391532A (en) * | 2020-11-16 | 2021-02-23 | 甘肃盈华环保科技有限公司 | Method for treating waste SCR catalyst by sodium roasting |
| CN115341063B (en) * | 2021-05-13 | 2024-01-02 | 中国科学院过程工程研究所 | Efficient reduction method for iron ore |
| CN115627311B (en) * | 2022-10-10 | 2024-03-29 | 山东大学 | Direct reduced iron system and method capable of preventing binding lost flow |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5235116A (en) * | 1975-09-12 | 1977-03-17 | Onoda Cement Co Ltd | Granulation method of iron ore powder |
| CN1161061A (en) * | 1994-10-17 | 1997-10-01 | 奥地利钢铁联合企业阿尔帕工业设备制造公司 | Process for producing liquid raw iron or steel basic products and iron sponge and plant for implementing it |
| US6235079B1 (en) * | 1997-12-20 | 2001-05-22 | Pohang Iron & Steel Co., Ltd. | Two step twin-single fluidized bed pre-reduction apparatus for pre-reducing fine iron ore, and method therefor |
| CN101117650A (en) * | 2007-09-12 | 2008-02-06 | 钢铁研究总院 | Method for fusion deacidizing quick-predeacidized trickle iron ore powder |
| CN102206723A (en) * | 2011-01-13 | 2011-10-05 | 北京首钢国际工程技术有限公司 | Air-base direct reduction iron-making method for reducing iron concentrate powder by self-reforming of gas rich in methane |
| KR20110119439A (en) * | 2010-04-27 | 2011-11-02 | 오미혜 | Composition of additive for metal sintering |
| CN102296139A (en) * | 2011-07-28 | 2011-12-28 | 北京科技大学 | Method for inhibiting bonding defluidization in fluidization reduction of iron ore powder |
-
2012
- 2012-10-24 CN CN201210408492.9A patent/CN102925611B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5235116A (en) * | 1975-09-12 | 1977-03-17 | Onoda Cement Co Ltd | Granulation method of iron ore powder |
| CN1161061A (en) * | 1994-10-17 | 1997-10-01 | 奥地利钢铁联合企业阿尔帕工业设备制造公司 | Process for producing liquid raw iron or steel basic products and iron sponge and plant for implementing it |
| US6235079B1 (en) * | 1997-12-20 | 2001-05-22 | Pohang Iron & Steel Co., Ltd. | Two step twin-single fluidized bed pre-reduction apparatus for pre-reducing fine iron ore, and method therefor |
| CN101117650A (en) * | 2007-09-12 | 2008-02-06 | 钢铁研究总院 | Method for fusion deacidizing quick-predeacidized trickle iron ore powder |
| KR20110119439A (en) * | 2010-04-27 | 2011-11-02 | 오미혜 | Composition of additive for metal sintering |
| CN102206723A (en) * | 2011-01-13 | 2011-10-05 | 北京首钢国际工程技术有限公司 | Air-base direct reduction iron-making method for reducing iron concentrate powder by self-reforming of gas rich in methane |
| CN102296139A (en) * | 2011-07-28 | 2011-12-28 | 北京科技大学 | Method for inhibiting bonding defluidization in fluidization reduction of iron ore powder |
Non-Patent Citations (2)
| Title |
|---|
| 添加剂对Fe2O3流化还原过程中粘结失流的影响;钟怡玮等;《中国稀土学报》;20120831;第30卷;第751页左栏第2段 * |
| 钟怡玮等.添加剂对Fe2O3流化还原过程中粘结失流的影响.《中国稀土学报》.2012,第30卷 |
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