CN106834604A - A kind of LF stoves composite fluxing medium and preparation method thereof - Google Patents
A kind of LF stoves composite fluxing medium and preparation method thereof Download PDFInfo
- Publication number
- CN106834604A CN106834604A CN201710053502.4A CN201710053502A CN106834604A CN 106834604 A CN106834604 A CN 106834604A CN 201710053502 A CN201710053502 A CN 201710053502A CN 106834604 A CN106834604 A CN 106834604A
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- China
- Prior art keywords
- parts
- cathode carbon
- composite fluxing
- stoves
- carbon block
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Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0025—Adding carbon material
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
- C21C7/0645—Agents used for dephosphorising or desulfurising
Abstract
The invention discloses a kind of LF stoves composite fluxing medium, it is prepared from by the aluminium ash of 70~100 parts of aluminum cell waste cathode carbon blocks and 0~30 part, aluminum cell waste cathode carbon block and aluminium ash are crushed to below 5mm, 10~20min of mixing, it is dried below 300 DEG C, make the water of compound less than the 0.5% of compound gross weight, obtain LF stove composite fluxing mediums；The present invention prepares deoxidation slagging agent using aluminum electrolysis waste cathode carbon block and aluminium ash, substantial amounts of heat is released in adding LF stoves containing charcoal in the aluminium and aluminum electrolysis waste cathode carbon block that contain in aluminium ash, be conducive to making up the thermal loss that LF stoves add composite fluxing medium process, and waste and old cathode carbon block can be molten steel recarburization；Aluminium solution waste and old cathode carbon block and aluminium ash are cheap, reduce the production cost of LF stove composite fluxing mediums.
Description
Technical field
The present invention relates to aluminium electroloysis waste cathode carbon block and the reutilization technology of aluminium ash, and in particular to a kind of LF stoves are combined slag making
Agent and preparation method thereof.
Background technology
Aluminium Industry is the basic industry of national economy, and important function is served in current social development.At present I
State's aluminium yield occupies No. 1 in the world, more than 15,000,000 tons, and still in the impetus of rapid growth.Meanwhile, aluminium electroloysis is being given
While national economy brings a large amount of valuable aluminium ingots, pollution is also brought.Maximum pollution sources are exactly electrolytic cell waste and old cathode.
Up to the present the accumulative discharge capacity of waste and old cell lining amount is up to more than 700 ten thousand tons, and the electrolytic aluminium factory of China is main
Using large prebaked cell for aluminum-reduction, electrolytic cell operation reaches its service life must just carry out large repairs, electrolytic cell during overhaul
Liner will be changed, the material produced during these overhauls referred to as overhaul waste residue or electrolytic cell waste liner etc..Waste and old cathode carbon block heap
Fluoride therein and cyanide permeate the ground in water when putting, polluted source.Additionally, also have very big harm to animals and plants around,
Influence balance of nature, makes crop production reduction.
LF stoves are ladle refining furnace, are external refining equipments main during steel is produced, and are mainly used in desulfurization, temperature and adjust
Section, the effect for improving Molten Steel Cleanliness and slag making, the key of LF stove slag making are slag rapid meltings and ensure suitable viscosity.Typically
For, after converter tapping, due to the influence of alloying, top slag temperature has the oxygen content in downward trend, and molten steel in ladle
It is too high.In addition, it is necessary to add a certain amount of slugging material, promote the rapid melting of slag charge.LF stove slag former conventional methods are exactly
Aluminium wire and fluorite are added, aluminium wire Main Function is deoxidation, and fluorite Main Function is the effect of Fast Slag Melting, and effect is general,
The compound action of deoxidation and slugging is not had simultaneously yet.
The content of the invention
For above-mentioned prior art exist deficiency, it is an object of the present invention to provide a kind of LF stoves composite fluxing medium and
Its preparation method, waste of aluminium electrolysis is re-used, and reduces the production cost of LF stove composite fluxing mediums.
In order to solve the above technical problems, present invention employs following technical scheme：
A kind of LF stoves composite fluxing medium, described composite fluxing medium includes following raw material：Aluminum cell waste cathode carbon block
With aluminium ash.
Further, in terms of parts by weight, it is made up of following raw material：Aluminum cell waste cathode carbon block is 70~100 parts,
Aluminium ash is 0~30 part, and the parts by weight sum of raw material is 100 parts.
Further, in terms of parts by weight, it is made up of following raw material：Aluminum cell waste cathode carbon block is 85 parts, aluminium ash
It it is 15 parts, the parts by weight sum of raw material is 100 parts.
Further, with 100 parts of weight basis, the composition of described aluminum cell waste cathode carbon block includes：C is 70
Part, F is 10 parts, and Na is 6 parts, and other contents are impurity；
With 100 parts of weight basis, described aluminium ash composition includes：Al is 10~25 parts, Al2O3It is 31.55 parts,
SiO2It it is 5.5 parts, MgO is 3 parts, CaO is 2 parts, Na2O is 3 parts, and other contents are impurity.
A kind of preparation method of LF stoves composite fluxing medium, comprises the following steps：
Step one：By the particle size reduction of aluminum cell waste cathode carbon block and aluminium ash to below 5mm；
Step 2：The cathode carbon pieces that step one is obtained mix 10~20min with aluminium ash by the composition weight of raw material, obtain
Compound；
Step 3：Mixture is dried below 300 DEG C, makes the water of compound less than compound gross weight
0.5%, obtain LF stove composite fluxing mediums.
Beneficial effects of the present invention are embodied in：
(1) present invention prepares deoxidation slagging agent using aluminum electrolysis waste cathode carbon block and aluminium ash, in aluminium ash the aluminium that contains and
Substantial amounts of heat is released in adding LF stoves containing charcoal in aluminum electrolysis waste cathode carbon block, is conducive to making up LF stoves addition composite fluxing medium
The thermal loss of process, and waste and old cathode carbon block can be molten steel recarburization.
(2) the waste and old cathode carbon block inside of aluminium electroloysis of the invention is conducive to improving metallurgical slag containing a certain amount of fluoride
The mobility of system, is conducive to the removal of field trash；
(3) aluminum metal contained in aluminium ash of the invention can be in LF stoves as deoxidation and desulfurization element；Contain in aluminium ash
There is substantial amounts of Al2O3The 2CaOSiO of insoluble sulphur can be suppressed2Generation, Al2O3Generation calcium aluminate (3CaO is combined with CaO
Al2O3And 12CaO7Al2O3) fusing point is low, stability is strong, promotes the effect of wash heat desulfurization.
(4) the aluminium solution waste and old cathode carbon block and aluminium ash that LF stoves composite fluxing medium of the invention is used are cheap, reduce
The production cost of LF stove composite fluxing mediums.
The present invention is further explained below in conjunction with specific embodiment.
Specific embodiment
A kind of LF stoves composite fluxing medium, including following raw material：Aluminum cell waste cathode carbon block and aluminium ash, with parts by weight
Meter, is made up of following raw material：Aluminum cell waste cathode carbon block is 70~100 parts, and aluminium ash is 0~30 part, the weight portion of raw material
Number sum is 100%.
Wherein：With 100 parts of weight basis, the composition of aluminum cell waste cathode carbon block includes：C is 70 parts, and F is 10
Part, Na is 6 parts, and other contents are impurity；
With 100 parts of weight basis, aluminium ash composition includes：Al is 10~25 parts, Al2O3It is 31.55 parts, SiO2It is 5.5
Part, MgO is 3 parts, and CaO is 2 parts, Na2O is 3 parts, and other contents are impurity.
A kind of preparation method of LF stoves composite fluxing medium, comprises the following steps：
Step one：Aluminum cell waste cathode carbon block and aluminium ash are crushed and sieved, its granularity is reached 5mm
Below；
Step 2：The cathode carbon pieces that step one is obtained, by the composition weight of raw material, carry out artificial and machinery and mix with aluminium ash
10~20min is closed, compound is obtained；
Step 3：Mixed material is interior in tunnel cave, shaft furnace or chain comb formula rotary kiln etc., dried below 300 DEG C, dry
Time is determined with the water of compound less than the 0.5% of compound gross weight；
Normal temperature is cooled to, compound is carried out into packing seals up for safekeeping, obtains LF stove composite fluxing mediums.
When in use, LF stoves composite fluxing medium of the invention (is added into compound slag making with 3kg/t in i.e. 1 ton LF stove ladle
Agent 3kg) amount add LF stove ladles in.
Specific embodiment of the invention given below is, it is necessary to explanation is the invention is not limited in implementing in detail below
Example, all equivalents done on the basis of technical scheme each fall within protection scope of the present invention.
Embodiment 1
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 100 parts.
A kind of method that utilization waste and old cathode carbon block prepares LF stove composite fluxing mediums, follows the steps below：
Step one：Waste and old cathode carbon block and each raw material are crushed and sieved, its granularity is reached below 5mm；
Step 2：Each raw material is weighed by the composition weight of raw material, artificial and mechanical mixture 15min is carried out, compound is obtained；
Step 3：Mixed material is dried in shaft furnace or chain comb formula rotary kiln, drying time is at 200 DEG C
0.5h；The mixing pellet of drying is carried out into packing to seal up for safekeeping.
When in use, by the LF stoves composite fluxing medium in the present embodiment, with 3kg/t, (i.e. 1 ton steel adds composite fluxing medium
Amount 3kg) is added in LF stove ladles.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Embodiment 2：
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 90 parts, and aluminium ash is 10 parts.
The preparation method and application method of the LF stove composite fluxing mediums of the present embodiment are same as Example 1.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Embodiment 3：
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 85 parts, and aluminium ash is 15 parts.
The preparation method and application method of the LF stove composite fluxing mediums of the present embodiment are same as Example 1.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Embodiment 4：
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 80 parts, and aluminium ash is 20 parts.
The preparation method and application method of the LF stove composite fluxing mediums of the present embodiment are same as Example 1.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Embodiment 5：
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 75 parts, and aluminium ash is 25 parts.
The preparation method and application method of the LF stove composite fluxing mediums of the present embodiment are same as Example 1.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Embodiment 6：
The present embodiment please provide a kind of LF stoves composite fluxing medium, in terms of parts by weight, be made up of following raw material：Aluminium cell
Waste and old cathode carbon block is 70 parts, and aluminium ash is 30 parts.
The preparation method and application method of the LF stove composite fluxing mediums of the present embodiment are same as Example 1.
The performance parameter of LF stoves composite fluxing medium manufactured in the present embodiment is as shown in table 1.
Aluminium electroloysis waste cathode carbon block main component of the invention contains charcoal and fluoride, can effectively lift ladle carburetting
The mobility and heat insulating ability of agent；As it can be seen from table 1 slag former of the invention has preferable carburetting effect carburetting absorptivity
Increasedd technique effect, because aluminium ash main component is aluminium and alundum (Al2O3), has good temperature raising and slugging to make
With both materials belong to the solid waste produced by aluminium electrolysis process.
Table 1 adds output experimental result
Claims (5)
1. a kind of LF stoves composite fluxing medium, it is characterised in that：Described composite fluxing medium includes following raw material：Aluminum cell waste
Cathode carbon pieces and aluminium ash.
2. LF stoves composite fluxing medium as claimed in claim 1, it is characterised in that：In terms of parts by weight, it is made up of following raw material：
Aluminum cell waste cathode carbon block is 70~100 parts, and aluminium ash is 0~30 part, and the parts by weight sum of raw material is 100 parts.
3. LF stoves composite fluxing medium as claimed in claim 2, it is characterised in that：In terms of parts by weight, it is made up of following raw material：
Aluminum cell waste cathode carbon block is 85 parts, and aluminium ash is 15 parts, and the parts by weight sum of raw material is 100 parts.
4. LF stove composite fluxing mediums as described in claim 1,2 or 3, it is characterised in that：It is described with 100 parts of weight basis
The composition of aluminum cell waste cathode carbon block include：C is 70 parts, and F is 10 parts, and Na is 6 parts, and other contents are impurity；
With 100 parts of weight basis, described aluminium ash composition includes：Al is 10~25 parts, Al2O3It is 31.55 parts, SiO2For
5.5 parts, MgO is 3 parts, and CaO is 2 parts, Na2O is 3 parts, and other contents are impurity.
5. the preparation method of the LF stove composite fluxing mediums described in claim 1, it is characterised in that：Comprise the following steps：
Step one：By the particle size reduction of aluminum cell waste cathode carbon block and aluminium ash to below 5mm；
Step 2：The cathode carbon pieces that step one is obtained mix 10~20min with aluminium ash by the composition weight of raw material, are mixed
Material；
Step 3：Mixture is dried below 300 DEG C, makes the water of compound less than the 0.5% of compound gross weight,
Obtain LF stove composite fluxing mediums.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201710053502.4A CN106834604A (en) | 2017-01-24 | 2017-01-24 | A kind of LF stoves composite fluxing medium and preparation method thereof |
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| CN201710053502.4A CN106834604A (en) | 2017-01-24 | 2017-01-24 | A kind of LF stoves composite fluxing medium and preparation method thereof |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109338033A (en) * | 2018-11-15 | 2019-02-15 | 西安建筑科技大学 | A kind of molten iron covering agent and preparation method |
| CN109609776A (en) * | 2019-02-14 | 2019-04-12 | 平罗县中兴碳素有限公司 | A method of copper cobalt in copper vessel slag is extracted using waste cathode of aluminum electrolytic cell carbon block |
| CN109735678A (en) * | 2019-02-21 | 2019-05-10 | 新疆中合大正冶金科技有限公司 | A method of converter slagging agent is produced using electrolytic aluminium slag from delining |
| CN110106312A (en) * | 2019-03-19 | 2019-08-09 | 新疆中合大正冶金科技有限公司 | A kind of technique using electrolytic aluminium carbon slag production LF slagging agent |
| CN111235354A (en) * | 2020-04-03 | 2020-06-05 | 北京璞域环保科技有限公司 | Production process of LF multifunctional deoxidation submerged arc slag |
| CN112048590A (en) * | 2020-08-01 | 2020-12-08 | 王强 | Resource utilization process for KR molten iron desulfurization cooperated with electrolytic aluminum hazardous waste carbon slag |
| CN113174463A (en) * | 2021-03-31 | 2021-07-27 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for producing high-carbon steel by utilizing cathode carbon blocks in LF ladle furnace resource |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109338033A (en) * | 2018-11-15 | 2019-02-15 | 西安建筑科技大学 | A kind of molten iron covering agent and preparation method |
| CN109609776A (en) * | 2019-02-14 | 2019-04-12 | 平罗县中兴碳素有限公司 | A method of copper cobalt in copper vessel slag is extracted using waste cathode of aluminum electrolytic cell carbon block |
| CN109735678A (en) * | 2019-02-21 | 2019-05-10 | 新疆中合大正冶金科技有限公司 | A method of converter slagging agent is produced using electrolytic aluminium slag from delining |
| CN110106312A (en) * | 2019-03-19 | 2019-08-09 | 新疆中合大正冶金科技有限公司 | A kind of technique using electrolytic aluminium carbon slag production LF slagging agent |
| CN110106312B (en) * | 2019-03-19 | 2020-11-10 | 新疆中合大正冶金科技有限公司 | Process for producing LF (ladle furnace) slagging agent by using electrolytic aluminum carbon slag |
| CN111235354A (en) * | 2020-04-03 | 2020-06-05 | 北京璞域环保科技有限公司 | Production process of LF multifunctional deoxidation submerged arc slag |
| CN112048590A (en) * | 2020-08-01 | 2020-12-08 | 王强 | Resource utilization process for KR molten iron desulfurization cooperated with electrolytic aluminum hazardous waste carbon slag |
| CN112048590B (en) * | 2020-08-01 | 2021-11-26 | 王强 | Resource utilization process for KR molten iron desulfurization cooperated with electrolytic aluminum hazardous waste carbon slag |
| CN113174463A (en) * | 2021-03-31 | 2021-07-27 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for producing high-carbon steel by utilizing cathode carbon blocks in LF ladle furnace resource |
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