CN104673970A - Oxidizing dephosphorization method for high-silicon high-phosphorus chromium-nickel-containing molten iron - Google Patents
Oxidizing dephosphorization method for high-silicon high-phosphorus chromium-nickel-containing molten iron Download PDFInfo
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- CN104673970A CN104673970A CN201510067334.5A CN201510067334A CN104673970A CN 104673970 A CN104673970 A CN 104673970A CN 201510067334 A CN201510067334 A CN 201510067334A CN 104673970 A CN104673970 A CN 104673970A
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Abstract
The invention relates to an oxidizing dephosphorization method for high-silicon high-phosphorus chromium-nickel-containing molten iron and belongs to the technical field of recycle of stainless steel dust. The concrete implementation plan comprises the following steps: preparing a dephosphorization agent containing 55-60wt% of BaO, 10-15wt% of CaO, 18-25wt% of CaF2, 3-5wt% of Cr2O3 and 1-5wt% of Fe2O3; melting high-silicon high-phosphorus chromium-nickel-containing pig iron in an electric furnace, blowing oxygen to remove silicon till the silicon content of molten iron is reduced to within 0.2wt% and drossing and removing silicon slag; and adding the dephosphorization agent at 1520-1560 DEG C to dephosphorize for 20-40 minutes and drossing and removing phosphorus slag. According to the method provided by the invention, chromium conservation by removing silicon and phosphorus is realized, the chromium loss rate is just 1.2-1.8%, the dephosphorization rate can reach 65-75%, and the dephosphorization effect is remarkable.
Description
Technical field
This invention belongs to dust recovery and reuse technology field in metallurgy industry producing stainless steel process, is specifically related to a kind of high silicon high phosphorus containing chromium ferronickel Water oxidize dephosphorizing method.
Background technology
Containing toxic heavy-metal elements such as a large amount of valuable nickel, chromium in dedusting ash of stainless steel, produce the dirt ash that stainless steel per ton can produce 30 ~ 40kg according to statistics, its bulk deposition is except causing the Precious Metals Resources such as nickel, chromium and wasting, the leaching of these poisoning metal element also can serious environment pollution, infringement HUMAN HEALTH, therefore must be effectively addressed, recycle.
Up to now, several modes such as direct landfill, solidification treatment, synthetic glass stupalith and direct-reduction recovery are mainly contained to the treatment process of dedusting ash of stainless steel.Wherein, direct-reduction reclaims and can utilize the noble metal element in dedusting ash of stainless steel to greatest extent thus produce economic benefit, also can realize the harmless treatment of dedusting ash of stainless steel.But direct-reduction reclaims the higher containing phosphorus content in chromium ferronickel water of dedusting ash of stainless steel acquisition, limited with addition of amount in stainless steel smelting process, therefore higher for these phosphorus is had to pour into block containing chromium ferronickel water and stack in a large number, directly cannot utilize in a large number, and then solve the Major Difficulties having become dedusting ash of stainless steel to recycle containing the dephosphorization problem in chromium ferronickel water relying on direct-reduction process dedusting ash of stainless steel to obtain.
Traditional utilizes CaO base oxidation sludge dephosphorization, not only causes a large amount of chromium oxidational losses, and generates a large amount of Cr
2o
3make dephosphorized slag " sclerosis ", almost lose dephosphorizing capacity completely.And although its dephosphorization efficiency is high during employing reduction slag system dephosphorization, easily occur " rephosphorization " phenomenon, method is complicated, simultaneously generation obnoxious flavour contaminate environment.
Summary of the invention
The present invention gives a kind of BaO-CaO compound dephosphorization slag system containing chromium ferronickel water reclaiming dedusting ash of stainless steel acquisition for direct-reduction, and utilize this kind of slag system to carry out the method for dephosphorization optimization, dephosphorization effect is remarkable, and method is simple, effectively can recycle noble metal element in dedusting ash, efficiently solve the dephosphorization problem containing chromium ferronickel water, recycle for dedusting ash of stainless steel and lay a good foundation.It is higher containing chromium ferronickel water phosphorus content that employing direct reduction process reclaims dedusting ash of stainless steel and obtains, for head it off, the invention discloses a kind of high silicon high phosphorus containing chromium ferronickel Water oxidize dephosphorizing method, baric slag system dephosphorization under oxidizing atmosphereLin Fenpeibi can be utilized according to this kind of method, noble metal element in effective recycling dedusting ash, and significantly can reduce the content of phosphorus in high silicon high-phosphorous chromium-nickel molten iron, establish the high silicon high phosphorus being applicable to promote according to this and contain chromium ferronickel Water oxidize dephosphorizing method.
A kind of high silicon high phosphorus, containing chromium ferronickel Water oxidize dephosphorizing method, comprises following concrete steps during operation.
(1) dephosphorizing agent is prepared
Each component percentage gets BaO, the CaO of 10 ~ 15%, the CaF of 18 ~ 25% of 55 ~ 60%
2, 3 ~ 5% Cr
2o
3with 1 ~ 5% Fe
2o
3prepare dephosphorizing agent compound; Toast the compound prepared at the temperature of 500 ~ 600 DEG C, baking time is 30 ~ 60min; Stirred by compound after baking and be crushed to 15 ~ 40 orders, obtained high silicon high phosphorus is containing the dephosphorizing agent needed for chromium nickel dephosphorization of molten iron.
(2) charging fusing
High silicon high phosphorus is loaded the electric furnace of 30 ~ 80t containing the chromium nickel pig iron, simultaneously according to 25 ~ 35kg/t
ironcome with addition of lime; Power after 1 ~ 2 hour, carry out oxygen blast and flux.
(3) oxygen blast desiliconization
After high silicon high phosphorus is melting down containing the chromium nickel pig iron, adopt furnace door oxygen lance to carry out oxygen blast, oxygen flow is 30 ~ 50m
3/ ht
iron, oxygen blast desiliconization 20 ~ 40min, within desiliconization to 0.2wt.%, stops oxygen blast, removes desiliconization slag.
(4) dephosphorization
Adopt the mode of material basket that the dephosphorizing agent obtained by step (1) is added electric furnace, the add-on of dephosphorizing agent is 90 ~ 110kg/t
iron; Argon bottom-blowing stirs, and argon flow amount is 0.3 ~ 0.5m
3/ h; At the temperature of 1520 ~ 1560 DEG C, smelt 20 ~ 40min, after reaction terminates, remove dephosphorized slag; If when there is rephosphorization phenomenon in dephosphorizing process, according to 5 ~ 10kg/t
ironratio to high silicon high phosphorus containing adding iron scale in chromium ferronickel water.
(5) hot charging AOD
After dephosphorization terminates, will continue in dephosphorization liquid iron charging AOD to smelt, and dephosphorized slag is managed separately deposit, recycle.
High silicon high phosphorus disclosed by the invention is containing chromium ferronickel Water oxidize dephosphorization optimization method, and its maximum feature is:
(1) the present invention utilizes oxygen blast desiliconization and baric slag system to carry out dephosphorization under oxidizing atmosphereLin Fenpeibi, and within high silicon high phosphorus can being reduced to 0.20wt.% containing silicone content in chromium ferronickel water, dephosphorization rate can reach 65% ~ 75%, possesses obvious dephosphorization effect.
(2) present invention achieves " desiliconization guarantor chromium " with " dephosphorization guarantor chromium ", chromium rate of loss is only 1.2 ~ 1.8%, effectively can recycle noble metal element in dedusting ash.
Accompanying drawing explanation
Fig. 1 is method flow schematic diagram of the present invention.
Embodiment
The high silicon high phosphorus that illustrated embodiment of the present invention adopts direct-reduction to reclaim dedusting ash of stainless steel and obtains is containing chromium ferronickel water, but this technological method is not limited to following embodiment.
In order to reduce the cost of dephosphorizing agent and realize industrialization, each constituent element of dephosphorizing agent uses industrial purification chemical product to replace pure reagent, that is:
(1) technical pure BaCO is used
3replace equivalent BaO, industrial BaCO
3middle BaCO
3>=99%;
(2) Cr is replaced with chromogen breeze
2o
3, Cr in chromogen breeze
2o
3>=77%.
(3) CaF is replaced with Natural Fluorite powder
2, CaF in fluorite
2>=95%;
(4) CaO is replaced with lime, wherein CaO >=90%;
(5) Fe is replaced with industrial iron scale
2o
3.
Be configured by weight percentage by above-mentioned raw materials, broken and machinery mixes prepares dephosphorizing agent, after oven dry, utilizes material basket to be added in electric furnace.
Embodiment 1
(1) dephosphorizing agent is prepared
Each component percentage gets the BaO of 60%, the CaO of 14%, the CaF of 18%
2, the Cr of 5%
2o
3with 3% Fe
2o
3prepare dephosphorizing agent compound; Toast the compound configured at 550 DEG C of temperature, baking time is 40min; Stirred by compound after baking and be crushed to 30 orders, obtained high silicon high phosphorus is containing the dephosphorizing agent needed for chromium nickel dephosphorization of molten iron.
(2) charging fusing
70t height silicon high phosphorus is loaded the electric furnace of 80t containing the chromium nickel pig iron, add 2t lime simultaneously; Power after 1 hour, carry out oxygen blast and flux.
(3) oxygen blast desiliconization
After high silicon high phosphorus is melting down containing the chromium nickel pig iron (melting down rear hot metal composition (wt.%) is as shown in table 1), adopt furnace door oxygen lance to carry out oxygen blast, oxygen flow is 40m
3/ ht
iron; After reaction 20min, stop oxygen blast, the silicone content recorded in molten iron is down to 0.17wt.% by 1.0wt.%, and carbon content is down to 3.21wt.% by 3.52wt.%, and chromium content is down to 8.61wt.% by 8.70wt.%, removes desiliconization slag.
Table 1
(4) dephosphorization
Adopt the mode of material basket that the dephosphorizing agent obtained by step (1) is added electric furnace, the add-on of dephosphorizing agent is 6.9t; Argon bottom-blowing stirs, and argon flow amount is 0.3m
3/ h; 25min is smelted at the temperature of 1543 ~ 1560 DEG C, silicone content in molten iron is down to 0.08wt.%, chromium content in molten iron is down to 8.58wt.%, chromium loss is 1.38%, phosphorus content in molten iron is down to 0.027wt.% by 0.086wt.%, dephosphorization rate is 68.6%, removes dephosphorized slag after reaction terminates.
(5) ingot casting or hot charging AOD
After dephosphorization terminates, by dephosphorization molten iron direct hot charging AOD, and dephosphorized slag is managed separately deposit, recycle.
Embodiment 2
(1) dephosphorizing agent is prepared
Each component percentage gets the BaO of 60%, the CaO of 14%, the CaF of 18%
2, the Cr of 5%
2o
3with 3% Fe
2o
3prepare dephosphorizing agent compound; Toast the compound configured at 550 DEG C of temperature, baking time is 40min; Stirred by compound after baking and be crushed to 30 orders, obtained high silicon high phosphorus is containing the dephosphorizing agent needed for chromium nickel dephosphorization of molten iron.
(2) charging fusing
70t height silicon high phosphorus is loaded the electric furnace of 80t containing the chromium nickel pig iron, add 2t lime simultaneously; Power after 1 hour, carry out oxygen blast and flux.
(3) oxygen blast desiliconization
After high silicon high phosphorus is melting down containing the chromium nickel pig iron (melting down rear hot metal composition (wt.%) is as shown in table 2), adopt furnace door oxygen lance to carry out oxygen blast, oxygen flow is 42m
3/ ht
iron; After reaction 25min, stop oxygen blast, the silicone content recorded in molten iron is down to 0.15wt.% by 1.15wt.%, and carbon content is being down to 3.19wt.% by 3.65wt.%, and chromium content is down to 8.53wt.% by 8.62wt.%, removes desiliconization slag.
Table 2
(4) dephosphorization
Adopt the mode of material basket that the dephosphorizing agent obtained by step (1) is added electric furnace, the add-on of dephosphorizing agent is 7t; Argon bottom-blowing stirs, and argon flow amount is 0.4m
3/ h; 28min is smelted at the temperature of 1523 ~ 1550 DEG C, silicone content in molten iron is down to 0.08wt.%, chromium content in molten iron is down to 8.51wt.%, chromium loss is 1.28%, phosphorus content in molten iron is down to 0.025wt.% by 0.095wt.%, dephosphorization rate is 73.7%, removes dephosphorized slag after reaction terminates.
(5) ingot casting or hot charging AOD
After dephosphorization terminates, by dephosphorization molten iron direct hot charging AOD, and dephosphorized slag is managed separately deposit, recycle.
Embodiment 3
(1) dephosphorizing agent is prepared
Each component percentage gets the BaO of 56%, the CaO of 15%, the CaF of 20%
2, the Cr of 4%
2o
3with 5% Fe
2o
3prepare dephosphorizing agent compound; Toast the compound configured at 550 DEG C of temperature, baking time is 40min; Stirred by compound after baking and be crushed to 30 orders, obtained high silicon high phosphorus is containing the dephosphorizing agent needed for chromium nickel dephosphorization of molten iron.
(2) charging fusing
70t height silicon high phosphorus is loaded the electric furnace of 80t containing the chromium nickel pig iron, add 2t lime simultaneously; Power after 1 hour, carry out oxygen blast and flux.
(3) oxygen blast desiliconization
After high silicon high phosphorus is melting down containing the chromium nickel pig iron (melting down rear hot metal composition (wt.%) is as shown in table 2), adopt furnace door oxygen lance to carry out oxygen blast, oxygen flow is 38m
3/ ht
iron; After reaction 25min, stop oxygen blast, sampling, the silicone content in molten iron is down to 0.16wt.% by 1.0wt.%, and carbon content is being down to 3.20wt.% by 3.52wt.%, and chromium content is down to 8.60wt.% by 8.70wt.%, removes desiliconization slag.
Table 3
(4) dephosphorization
Adopt the mode of material basket that the dephosphorizing agent obtained by step (1) is added electric furnace, the add-on of dephosphorizing agent is 7.2t; Argon bottom-blowing stirs, and argon flow amount is 0.42m
3/ h; 28min is smelted at the temperature of 1530 ~ 1560 DEG C, silicone content in molten iron is down to 0.07wt.%, chromium content in molten iron is down to 8.57wt.%, chromium loss is 1.49%, phosphorus content in molten iron is down to 0.023wt.% by 0.086wt.%, dephosphorization rate is 73.3%, removes dephosphorized slag after reaction terminates.
(5) ingot casting or hot charging AOD
After dephosphorization terminates, by dephosphorization molten iron direct hot charging AOD, and dephosphorized slag is managed separately deposit, recycle.
This explanation is write according to concrete preferred embodiment, specific embodiment of the invention scheme can not be regarded as and be confined to this explanation, to those skilled in the art, under the prerequisite not departing from general plotting of the present invention, framework carries out flexible and changeablely deriving a series of product.Only make some simple deductions and replacement, all should be considered as the protection domain belonging to claims of the present invention.
Claims (1)
1. high silicon high phosphorus is containing a chromium ferronickel Water oxidize dephosphorizing method, it is characterized in that carrying out according to the following steps:
(1) dephosphorizing agent is prepared: each component percentage gets BaO, the CaO of 10 ~ 15%, the CaF of 18 ~ 25% of 55 ~ 60%
2, 3 ~ 5% Cr
2o
3with 1 ~ 5% Fe
2o
3prepare dephosphorizing agent compound, toast at the temperature of 500 ~ 600 DEG C to the compound prepared, baking time is 30 ~ 60min, is stirred by the compound after baking and is crushed to 15 ~ 40 orders, obtained dephosphorizing agent;
(2) charging fusing: the electric furnace high silicon high phosphorus being loaded 30 ~ 80t containing the chromium nickel pig iron, simultaneously according to 25 ~ 35kg/t
ironcome with addition of lime, power after 1 ~ 2 hour, carry out oxygen blast and flux;
(3) oxygen blast desiliconization: after high silicon high phosphorus is melting down containing the chromium nickel pig iron, adopt furnace door oxygen lance to carry out oxygen blast, oxygen flow is 30 ~ 50m
3/ ht
iron, oxygen blast desiliconization time is 20 ~ 40min, within desiliconization to 0.2wt.%, stops oxygen blast, removes desiliconization slag;
(4) dephosphorization: adopt the mode of material basket that the dephosphorizing agent obtained by step (1) is added electric furnace, the add-on of dephosphorizing agent is 90 ~ 110kg/t
iron, argon bottom-blowing stirs, and argon flow amount is 0.3 ~ 0.5m
3/ h, smelts 20 ~ 40min at the temperature of 1520 ~ 1560 DEG C, removes dephosphorized slag, if when there is rephosphorization phenomenon in dephosphorizing process, according to 5 ~ 10kg/t after reaction terminates
ironratio to high silicon high phosphorus containing adding iron scale in chromium ferronickel water;
(5) hot charging AOD: after dephosphorization terminates, will continue in dephosphorization liquid iron charging AOD to smelt.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108193020A (en) * | 2017-12-28 | 2018-06-22 | 江苏江南铁合金有限公司 | A kind of method of phosphorous nickel iron refining dephosphorization |
| CN108588336A (en) * | 2018-06-07 | 2018-09-28 | 上海应用技术大学 | A kind of nano oxidized Dephosphorising agent and preparation method being suitable for smelting ultralow phosphorus stainless steel |
| CN112708714A (en) * | 2020-12-18 | 2021-04-27 | 邢台德勤工矿工程有限公司 | Ferronickel refining process |
| CN114875206A (en) * | 2022-04-11 | 2022-08-09 | 辽宁石源科技有限公司 | Phosphorus removal and chromium protection double process for smelting chromium-containing high-phosphorus metal liquid from laterite-nickel ore |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108193020A (en) * | 2017-12-28 | 2018-06-22 | 江苏江南铁合金有限公司 | A kind of method of phosphorous nickel iron refining dephosphorization |
| CN108588336A (en) * | 2018-06-07 | 2018-09-28 | 上海应用技术大学 | A kind of nano oxidized Dephosphorising agent and preparation method being suitable for smelting ultralow phosphorus stainless steel |
| CN112708714A (en) * | 2020-12-18 | 2021-04-27 | 邢台德勤工矿工程有限公司 | Ferronickel refining process |
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| CN114875206A (en) * | 2022-04-11 | 2022-08-09 | 辽宁石源科技有限公司 | Phosphorus removal and chromium protection double process for smelting chromium-containing high-phosphorus metal liquid from laterite-nickel ore |
| CN114875206B (en) * | 2022-04-11 | 2023-09-19 | 辽宁石源科技有限公司 | Double dephosphorization and chromium protection process for smelting chromium-containing high-phosphorus metal liquid from laterite-nickel ore |
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