CN111777054A - Method for removing fluorine by using aluminum electrolysis waste cathode carbon block through microwave-ultrasonic wave-alkaline leaching - Google Patents
Method for removing fluorine by using aluminum electrolysis waste cathode carbon block through microwave-ultrasonic wave-alkaline leaching Download PDFInfo
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- CN111777054A CN111777054A CN202010644698.6A CN202010644698A CN111777054A CN 111777054 A CN111777054 A CN 111777054A CN 202010644698 A CN202010644698 A CN 202010644698A CN 111777054 A CN111777054 A CN 111777054A
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 151
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 123
- 239000002699 waste material Substances 0.000 title claims abstract description 72
- 238000000034 method Methods 0.000 title claims abstract description 53
- 238000002386 leaching Methods 0.000 title claims abstract description 51
- 239000011737 fluorine Substances 0.000 title claims abstract description 30
- 229910052731 fluorine Inorganic materials 0.000 title claims abstract description 30
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 28
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 28
- 238000005868 electrolysis reaction Methods 0.000 title claims abstract description 24
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 title claims abstract 10
- 239000002245 particle Substances 0.000 claims abstract description 44
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 claims abstract description 24
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 claims abstract description 23
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 23
- 239000001301 oxygen Substances 0.000 claims abstract description 23
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 23
- 238000000227 grinding Methods 0.000 claims abstract description 21
- 239000007789 gas Substances 0.000 claims abstract description 19
- 230000001681 protective effect Effects 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 13
- 239000003513 alkali Substances 0.000 claims abstract description 11
- 238000001914 filtration Methods 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- 239000011343 solid material Substances 0.000 claims abstract description 5
- 238000012216 screening Methods 0.000 claims abstract description 3
- 229910001610 cryolite Inorganic materials 0.000 claims description 19
- 238000002955 isolation Methods 0.000 claims description 19
- 230000008569 process Effects 0.000 claims description 19
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 18
- 239000000706 filtrate Substances 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 12
- KWYUFKZDYYNOTN-UHFFFAOYSA-M potassium hydroxide Substances [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 9
- 238000000926 separation method Methods 0.000 claims description 9
- 238000003756 stirring Methods 0.000 claims description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 8
- 238000001704 evaporation Methods 0.000 claims description 7
- 238000004321 preservation Methods 0.000 claims description 7
- 229910052786 argon Inorganic materials 0.000 claims description 6
- 239000003792 electrolyte Substances 0.000 claims description 6
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 claims description 4
- 229910052863 mullite Inorganic materials 0.000 claims description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims description 4
- 239000010453 quartz Substances 0.000 claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052593 corundum Inorganic materials 0.000 claims description 3
- 239000010431 corundum Substances 0.000 claims description 3
- 238000004064 recycling Methods 0.000 claims description 3
- 230000008020 evaporation Effects 0.000 claims description 2
- 239000002910 solid waste Substances 0.000 abstract 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 20
- 239000000126 substance Substances 0.000 description 15
- 150000002222 fluorine compounds Chemical class 0.000 description 9
- 230000008018 melting Effects 0.000 description 9
- 238000002844 melting Methods 0.000 description 9
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 6
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 6
- 239000011575 calcium Substances 0.000 description 6
- 229910052791 calcium Inorganic materials 0.000 description 6
- 230000001590 oxidative effect Effects 0.000 description 6
- 239000011734 sodium Substances 0.000 description 6
- 229910052708 sodium Inorganic materials 0.000 description 6
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 6
- 238000001228 spectrum Methods 0.000 description 6
- 239000011573 trace mineral Substances 0.000 description 6
- 235000013619 trace mineral Nutrition 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 230000003472 neutralizing effect Effects 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
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- 239000003795 chemical substances by application Substances 0.000 description 3
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- 238000001000 micrograph Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000011775 sodium fluoride Substances 0.000 description 3
- 235000013024 sodium fluoride Nutrition 0.000 description 3
- 241001465754 Metazoa Species 0.000 description 2
- 239000003575 carbonaceous material Substances 0.000 description 2
- 238000006115 defluorination reaction Methods 0.000 description 2
- 239000002920 hazardous waste Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 231100000252 nontoxic Toxicity 0.000 description 2
- 230000003000 nontoxic effect Effects 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000002341 toxic gas Substances 0.000 description 2
- 238000004131 Bayer process Methods 0.000 description 1
- 206010033799 Paralysis Diseases 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- 229910001634 calcium fluoride Inorganic materials 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 150000002221 fluorine Chemical class 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000005087 graphitization Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/48—Halides, with or without other cations besides aluminium
- C01F7/50—Fluorides
- C01F7/54—Double compounds containing both aluminium and alkali metals or alkaline-earth metals
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention discloses a method for removing fluorine by the microwave-ultrasonic-alkaline leaching cooperation of aluminum electrolysis waste cathode carbon blocks, and relates to an aluminum electrolysis waste cathode treatment technology. Crushing waste cathode carbon blocks, screening to obtain particles, putting the particles into a crucible, putting the crucible into a high-temperature microwave reactor, introducing oxygen to remove cyanide in the heating process, introducing protective gas, and performing microwave high-temperature roasting; finely grinding the roasted cathode carbon block, pouring finely ground carbon powder into alkali liquor, and carrying out alkali liquor leaching treatment by ultrasonic assistance; and after leaching, separating and filtering, and drying the solid materials to obtain the regenerated carbon powder with the purity of over 90 percent. The method can effectively remove fluoride in the cathode carbon block, so that the carbon block can be recycled, the method is simple and efficient to operate, and the harmless utilization of the aluminum electrolysis solid waste can be realized.
Description
Technical Field
The invention relates to an aluminum electrolysis waste cathode treatment technology, in particular to a method for removing fluorine by the cooperation of microwave-ultrasonic wave-alkaline leaching of aluminum electrolysis waste cathode carbon blocks.
Background
In the production process of electrolytic aluminum, the new electrolytic cell can be replaced within 5-8 years, and the replaced cathode is a waste cathode. The main reason for replacement is that the aluminum electrolysis cell is broken by the infiltration of impurities such as sodium fluoride, and the liquid in the cell leaks out from the crack opening, so that the production cannot be continued. In recent years, with the rapid increase of aluminum demand, the aluminum electrolysis industry is rapidly developed, the scale of production lines is rapidly increased, and a large amount of waste cathode carbon blocks are generated by replacing cathodes every time, so that the waste cathode carbon blocks are treated as problems which are urgently needed to be solved by various aluminum electrolysis plants.
The waste cathode carbon blocks mainly comprise carbonaceous materials and electrolyte components, wherein the content of the carbonaceous materials is 30-70%, and the graphitization degree is as high as 80-90%; the electrolyte contains 30-70% of electrolyte components, and the main components are cryolite, sodium fluoride, calcium fluoride, cyanide and the like, and the mineral material is rich in graphitized carbon and fluorine salt.
At present, domestic treatment of waste cathodes is not paid enough attention, most of the waste cathodes are stacked in the open air, and the environment is greatly polluted, which is mainly shown in the following steps: 1) fluoride and cyanide in the waste cathode permeate into soil along with rainwater, so that the yield of crops is reduced; 2) irreversible influence is generated on the growth of animals and plants, so that the plants become black, the joints of animals deform and even paralysis; 3) and when the glass is in a humid condition for a long time, harmful gases can be released to pollute the atmosphere. Thus, the spent cathode is characterized as a hazardous waste. Meanwhile, available resources in the waste cathode are not effectively recovered, so that the resources are seriously wasted, and in recent years, the national environment protection is more and more emphasized. In 2016, the overhaul slag of the aluminum electrolysis cell is definitely listed in the national hazardous waste record (No. 39 of the Ministry of environmental protection in 2016), and becomes one of the main solid environmental pollution sources in the aluminum electrolysis industry, so that the recycling of the effective components of the waste cathode is urgent.
The main treatment methods of the waste cathode include a wet method and a fire method, which are physical separation, high-temperature heat treatment and chemical leaching methods respectively. The fire method is mainly applied to harmless treatment to eliminate harmful components such as fluoride, cyanide and the like in the carbon block, the principle is to separate the harmful components according to the combustion of the substances and different boiling points, at present, natural gas is mainly adopted for incineration, and common muffle furnaces and tubular furnaces have the disadvantages of long treatment time, slow heating rate, long heat preservation time and the like. The wet method is mainly applied to comprehensive utilization of waste cathode resources, so that each component is separated. The wet method is divided into a physical separation method and a chemical leaching method, wherein the physical separation method is to separate carbon from fluoride according to the factors of solubility, density, surface performance and the like. Chemical leaching is also used for separating carbon and fluoride, the separation is carried out by utilizing the difference of chemical properties, and finally, carbon and electrolyte with higher purity are obtained. The invention solves the problems of incomplete reaction, long treatment time and waste liquid to a certain extent, and greatly shortens the production efficiency.
Disclosure of Invention
The invention aims to provide a method for removing fluorine by the cooperation of microwave-ultrasonic-alkaline leaching of waste cathode carbon blocks in aluminum electrolysis, which solves the problems of long treatment time, large waste liquid amount, difficult treatment and incomplete reaction.
In order to solve the technical problems, the invention adopts the following technical scheme: a method for removing fluorine by the cooperation of microwave-ultrasonic wave-alkaline leaching of aluminum electrolysis waste cathode carbon blocks is characterized by comprising the following steps:
a) crushing waste cathode carbon blocks of an aluminum electrolytic cell, screening to obtain particles with the particle size of 1-3 cm, returning to the crushing step when the particle size is larger than 3cm, and entering a grinding stage when the particle size is smaller than 1 cm;
b) putting the crushed waste cathode carbon blocks into a crucible, placing the crucible in a high-temperature microwave reactor, introducing a small amount of oxygen when the temperature of the waste cathode carbon blocks is raised to 300 ℃, stopping introducing the oxygen and continuously introducing protective gas when the temperature reaches 400 ℃, and roasting the waste cathode carbon blocks at high temperature by microwave under the environment of the protective gas to physically separate cryolite and fluoride electrolyte in the carbon blocks from the cathode carbon;
c) carrying out fine grinding treatment on the cathode carbon block after microwave roasting to obtain carbon powder with the granularity of less than 100 meshes;
d) pouring the finely ground carbon powder into alkali liquor, and carrying out alkali liquor leaching treatment by ultrasonic assistance to remove residual fluoride and cyanide in the carbon powder;
e) and after leaching, separating and filtering to obtain solid materials and filtrate respectively, drying the solid materials to obtain regenerated carbon powder with the purity of over 90%, and performing evaporation separation on the filtrate for recycling.
According to a further technical scheme, in the microwave high-temperature roasting process in the step b), microwaves are directly acted on the waste cathode carbon blocks for high-temperature roasting, the microwave power is 1-10 kW, the microwave frequency is 2450 +/-50 or 915 +/-50 MHz, the heating rate is 30-150 ℃/min, the roasting temperature is 1000-1200 ℃, and the heat preservation time is 30-90 min.
A further technical proposal is that the middle part of the crucible adopted in the step b) is provided with an isolation net, and through holes with the diameter less than 0.5cm are distributed on the isolation net.
The further technical proposal is that the crucible is one of corundum crucible, quartz crucible and mullite crucible
A further technical scheme is that the temperature measuring device adopted in the step b) is a thermocouple temperature measuring device or an infrared temperature measuring device.
A further technical proposal is that the protective gas used in the step b) is at least one of argon and nitrogen.
The further technical scheme is that the alkali liquor selected in the step d) is at least one of NaOH and KOH, the solution concentration is 0.4-1.2 mol/L of alkali liquor, and the solid-liquid ratio is 1: 2 to 15.
The further technical scheme is that the ultrasonic power adopted in the ultrasonic-assisted alkaline leaching process in the step d) is 2-10 kW, the treatment time is 30-120 min, the water bath temperature is 50-90 ℃, and the stirring speed is 600-3000 r/min.
The reaction mechanism is as follows:
according to the difference of the wave absorbing performance of each substance, the carbon block has stronger wave absorbing performance, so that the temperature of the carbon block material can be rapidly increased, when the cyanide oxidation temperature is reached and the oxidation temperature of the carbon block is not reached, the cyanide in the carbon block is oxidized by a small amount of oxygen or oxidizing gas to form nontoxic gas to be removed, most of the cyanide can be removed in the process, and the loss of the carbon block is negligible.
After cyanide is oxidized and removed, the temperature is raised and protective gas is introduced at the same time, so that the temperature is rapidly raised to the melting point of fluoride to separate out the fluoride, primary defluorination treatment is carried out, and the precipitate left at the bottom of the crucible through the separation net is recovered, wherein the main component of the precipitate is cryolite and can be directly recovered and reused.
The method has the advantages that chemical reactions are used for all undecomposed fluorides, the particle surfaces are exposed under the action of ultrasonic cavitation effect, the high temperature and high pressure generated by the cavitation effect accelerate the chemical reactions, the treatment time is shortened, meanwhile, the method can be used for industrial production, and the method has guiding significance for treating aluminum electrolysis waste cathodes to recover cryolite and carbon in large batches.
Compared with the prior art, the invention has the beneficial effects that:
1. under the microwave environment, all substances in the waste cathode carbon blocks have different wave-absorbing properties, wherein the carbon has stronger wave-absorbing property, so that the carbon blocks are heated rapidly under the microwave to reach the melting points of all substances except the carbon blocks, and the substances are mainly fluorides (NaF and CaF)2、Na3AlF6) The melting point of the fluoride removal agent is reached, so that a bond layer between the fluoride removal agent and surrounding carbon is opened, and the fluoride removal agent finally flows out as white liquid, so that most of fluoride is removed, the removal rate of the fluoride in the process is as high as 50-70%, the subsequent treatment process is greatly shortened, cyanide is oxidized to form non-toxic gas which can be directly discharged, and no toxic gas is generated in the process.
2. The separation net is arranged in the crucible, so that fluorine-containing substances in a molten state mainly comprise cryolite and pass through the separation net to be left at the bottom of the crucible, and the cryolite is convenient to recycle.
3. The ground carbon powder is put into a plastic beaker and soaked in alkali liquor, the material roasted at high temperature by microwave is subjected to secondary deep defluorination by ultrasonic cavitation oscillation, stirring and alkaline leaching synergistic treatment in the water bath heating process, the fluoride in the waste cathode carbon block is effectively removed by utilizing the ultrasonic air-talk effect and the Bayer process, and the removal rate of the fluoride in the aluminum electrolysis waste cathode carbon block is up to 90-96%.
4. The particle size of the crushed waste cathode carbon blocks is limited to 1-3 cm, so that microwave penetration heating is facilitated, and fluorides can be fully separated out in a short time. The particle size is too large to be fast separated out, and the particle size is too small to be influenced by the protective gas and is easy to blow out along with the gas.
Drawings
FIG. 1 is a schematic flow chart of the present invention.
Fig. 2 is a surface scanning electron micrograph of an untreated waste cathode carbon block of example 6.
Fig. 3 is an EDS energy spectrum of an untreated spent cathode carbon block of example 6.
FIG. 4 is a scanning electron microscope image of the surface of the waste cathode carbon block after fluorine removal in example 6.
Fig. 5 is an EDS energy spectrum of the waste cathode carbon block after fluorine removal in example 6.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
In the embodiment, the waste cathode carbon block comprises 58.4% of carbon, 14.7% of oxygen, 12.7% of fluorine, 9.37% of sodium, 0.8% of calcium and the balance of alumina and trace elements according to weight percentage.
Crushing the waste cathode carbon blocks into particles with the particle size of 1-3 cm, crushing the particles again when the particle size is larger than 3cm, and grinding the particles when the particle size is smaller than 1cm, then putting the cathode carbon blocks into a crucible, wherein the crucible is a quartz crucible, putting a sample above an isolation net, putting 2/3 of the sample volume occupying the volume of the crucible, and putting the crucible into high-temperature microwave equipment.
Introducing a small amount of oxygen when the temperature of the waste cathode carbon block is raised to 300 ℃, oxidizing and removing most of cyanide, stopping introducing the oxygen and continuously introducing argon as protective gas when the temperature reaches 400 ℃, and carrying out high-temperature microwave roasting treatment on the cathode carbon block, wherein the roasting temperature is 1000 ℃, and the heat preservation time is 30 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. In the whole process, the microwave frequency of the adopted microwave equipment is 2450 +/-50 MHz, the microwave power is 1000W, the heating rate is 30 ℃/min, and a thermocouple is adopted to measure the temperature of the waste cathode carbon block.
Recovering white crystal substances left below the isolation net after treatment by high-temperature microwave equipment, removing a small amount of white attachments on the surface of the carbon blocks on the isolation net, and then putting the carbon blocks into a grinding machine for grinding to obtain carbon powder with the granularity of below 100 meshes.
Putting the ground carbon powder into a sodium hydroxide solution with the concentration of 0.4mol/L, wherein the solid-liquid ratio is 1: 2, leaching under the condition of ultrasonic water bath, wherein the ultrasonic leaching power is 2000W, the time is 30min, the temperature of the water bath is 50 ℃, and the stirring speed is 600 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue;
and (3) placing the leached filter residue in a vessel, placing the vessel in a constant-temperature drying oven at the temperature of 60 ℃ for 12 hours, and detecting to obtain that the fluorine removal rate is up to 90%. Neutralizing the filtrate, evaporating to obtain cryolite, and reusing.
Example 2
In the embodiment, the waste cathode carbon block comprises 58.4% of carbon, 14.7% of oxygen, 12.7% of fluorine, 9.37% of sodium, 0.8% of calcium and the balance of alumina and trace elements according to weight percentage.
Crushing the waste cathode carbon blocks into particles with the particle size of 1-3 cm, crushing the particles again when the particle size is larger than 3cm, and grinding the particles when the particle size is smaller than 1cm, then putting the cathode carbon blocks into a crucible, wherein the crucible is a corundum crucible, a sample is placed above an isolation net, 2/3 of the volume of the sample occupying the volume of the crucible is put into the crucible, and the crucible is put into high-temperature microwave equipment.
Introducing a small amount of oxygen when the temperature of the waste cathode carbon block is raised to 300 ℃, oxidizing and removing most of cyanide, stopping introducing the oxygen and continuously introducing argon as protective gas when the temperature reaches 400 ℃, and carrying out high-temperature microwave roasting treatment on the cathode carbon block at 1075 ℃ for 50 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. In the whole process, the microwave frequency of the adopted microwave equipment is 2450 +/-50 MHz, the microwave power is 3kW, the heating rate is 40 ℃/min, and the waste cathode carbon blocks are subjected to temperature measurement by adopting infrared.
Recovering white crystal substances left below the isolation net after treatment by high-temperature microwave equipment, removing a small amount of white attachments on the surface of the carbon blocks on the isolation net, and then putting the carbon blocks into a grinding machine for grinding to obtain carbon powder with the granularity of below 100 meshes.
Putting the ground carbon powder into a sodium hydroxide solution with the concentration of 0.6mol/L, wherein the solid-liquid ratio is 1: leaching under the condition of ultrasonic water bath, wherein the ultrasonic leaching power is 4000W, the time is 50min, the temperature of the water bath is 60 ℃, and the stirring speed is 1000 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue;
and (3) placing the leached filter residue in a vessel, placing the vessel in a constant-temperature drying oven at the temperature of 60 ℃ for 12 hours, and detecting to obtain that the fluorine removal rate is up to 92%. Neutralizing the filtrate, evaporating to obtain cryolite, and reusing.
Example 3
In the embodiment, the waste cathode carbon block comprises 58.4% of carbon, 14.7% of oxygen, 12.7% of fluorine, 9.37% of sodium, 0.8% of calcium and the balance of alumina and trace elements according to weight percentage.
Crushing the waste cathode carbon blocks into particles with the particle size of 1-3 cm, crushing the particles again when the particle size is larger than 3cm, and grinding the particles when the particle size is smaller than 1cm, then putting the cathode carbon blocks into a crucible, wherein the crucible is a quartz crucible, putting a sample above an isolation net, putting 2/3 of the sample volume occupying the volume of the crucible, and putting the crucible into high-temperature microwave equipment.
Introducing a small amount of oxygen when the temperature of the waste cathode carbon block is raised to 300 ℃, oxidizing and removing most of cyanide, stopping introducing the oxygen and continuously introducing argon as protective gas when the temperature reaches 400 ℃, and carrying out high-temperature microwave roasting treatment on the cathode carbon block, wherein the roasting temperature is 1120 ℃, and the heat preservation time is 60 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. In the whole process, the microwave frequency of the adopted microwave equipment is 915 +/-50 MHz, the microwave power is 5000W, the heating rate is 60 ℃/min, and a thermocouple is adopted to measure the temperature of the waste cathode carbon block.
Recovering white crystal substances left below the isolation net after treatment by high-temperature microwave equipment, removing a small amount of white attachments on the surface of the carbon blocks on the isolation net, and then putting the carbon blocks into a grinding machine for grinding to obtain carbon powder with the granularity of below 100 meshes.
Putting the ground carbon powder into a potassium hydroxide solution with the concentration of 0.8mol/L, wherein the solid-liquid ratio is 1: 8, leaching under the condition of ultrasonic water bath, wherein the ultrasonic leaching power is 5000W, the time is 60min, the temperature of the water bath is 70 ℃, and the stirring speed is 1000 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue;
and (3) placing the leached filter residue in a vessel, placing the vessel in a constant-temperature drying oven at the temperature of 60 ℃ for 12 hours, and detecting to obtain that the fluorine removal rate is up to 93%. Neutralizing the filtrate, evaporating to obtain cryolite, and reusing.
Example 4
In the embodiment, the waste cathode carbon block comprises 58.4% of carbon, 14.7% of oxygen, 12.7% of fluorine, 9.37% of sodium, 0.8% of calcium and the balance of alumina and trace elements according to weight percentage.
Crushing the waste cathode carbon blocks into particles with the particle size of 1-3 cm, crushing the particles again when the particle size is larger than 3cm, and grinding the particles when the particle size is smaller than 1cm, then putting the cathode carbon blocks into a crucible, wherein the crucible is a mullite crucible, a sample is placed above an isolation net, 2/3 of the sample volume occupying the volume of the crucible is put into the crucible, and the crucible is put into high-temperature microwave equipment.
Introducing a small amount of oxygen when the temperature of the waste cathode carbon block is raised to 300 ℃, oxidizing and removing most of cyanide, stopping introducing the oxygen and continuously introducing argon as protective gas when the temperature reaches 400 ℃, and carrying out high-temperature microwave roasting treatment on the cathode carbon block at 1150 ℃ for 50 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. In the whole process, the microwave frequency of the adopted microwave equipment is 915 +/-50 MHz, the microwave power is 8000W, the heating rate is 100 ℃/min, and a thermocouple is adopted to measure the temperature of the waste cathode carbon block.
Recovering white crystal substances left below the isolation net after treatment by high-temperature microwave equipment, removing a small amount of white attachments on the surface of the carbon blocks on the isolation net, and then putting the carbon blocks into a grinding machine for grinding to obtain carbon powder with the granularity of below 150 meshes.
Putting the ground carbon powder into a mixed solution of potassium hydroxide and sodium hydroxide with the concentration of 1.0mol/L, wherein the solid-to-liquid ratio is 1: 10, leaching under the condition of ultrasonic water bath, wherein the ultrasonic leaching power is 5000W, the time is 75min, the temperature of the water bath is 80 ℃, and the stirring speed is 2500 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue;
and (3) placing the leached filter residue in a vessel, placing the vessel in a constant-temperature drying oven at the temperature of 60 ℃ for 12 hours, and detecting to obtain that the fluorine removal rate is up to 95%. Neutralizing the filtrate, evaporating to obtain cryolite, and reusing.
Example 5
In the embodiment, the waste cathode carbon block comprises 58.4% of carbon, 14.7% of oxygen, 12.7% of fluorine, 9.37% of sodium, 0.8% of calcium and the balance of alumina and trace elements according to weight percentage.
Crushing the waste cathode carbon blocks into particles with the particle size of 1-3 cm, crushing the particles again when the particle size is larger than 3cm, and grinding the particles when the particle size is smaller than 1cm, then putting the cathode carbon blocks into a crucible, wherein the crucible is a mullite crucible, a sample is placed above an isolation net, 2/3 of the sample volume occupying the volume of the crucible is put into the crucible, and the crucible is put into high-temperature microwave equipment.
Introducing a small amount of oxygen when the temperature of the waste cathode carbon block is raised to 300 ℃, oxidizing and removing most of cyanide, stopping introducing the oxygen and continuously introducing nitrogen as protective gas when the temperature reaches 400 ℃, and carrying out high-temperature microwave roasting treatment on the cathode carbon block, wherein the roasting temperature is 1200 ℃, and the heat preservation time is 90 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. In the whole process, the microwave frequency of the adopted microwave equipment is 2450 +/-50 MHz, the microwave power is 10000W, the heating rate is 150 ℃/min, and a thermocouple is adopted to measure the temperature of the waste cathode carbon block.
Recovering white crystal substances left below the isolation net after treatment by high-temperature microwave equipment, removing a small amount of white attachments on the surface of the carbon blocks on the isolation net, and then putting the carbon blocks into a grinding machine for grinding to obtain carbon powder with the granularity of below 120 meshes.
Putting the ground carbon powder into a potassium hydroxide solution with the concentration of 1.2mol/L, wherein the solid-liquid ratio is 1: 15, leaching under the condition of ultrasonic water bath, wherein the ultrasonic leaching power is 10000W, the time is 120min, the temperature of the water bath is 90 ℃, and the stirring speed is 3000 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue;
and (3) placing the leached filter residue in a vessel, placing the vessel in a constant-temperature drying oven at the temperature of 60 ℃ for 12 hours, and detecting to obtain that the fluorine removal rate is up to 98%. Neutralizing the filtrate, evaporating to obtain cryolite, and reusing.
Example 6
The waste cathode carbon block contains 58.4 percent of carbon, 14.7 percent of oxygen, 12.7 percent of fluorine, 9.37 percent of sodium, 0.8 percent of calcium and the balance of alumina and trace elements. As shown in figure 1, microwave is adopted to perform microwave high-temperature treatment on the cathode carbon block, wherein the treatment temperature is 1200 ℃. The power is 2500W, the heating rate is 30 ℃/min, and the heat preservation time is 90 min. This process brings the cryolite and other fluorides to a melting point, allowing them to separate from the carbon. And in the early stage of microwave treatment, a small amount of oxygen is introduced when the temperature of the waste cathode carbon block is raised to 300 ℃, most of cyanide is removed by oxidation, nitrogen is continuously introduced as protective gas after the temperature reaches 400 ℃, and then the cathode carbon block is subjected to high-temperature microwave roasting treatment.
And grinding the roasted cathode carbon block to obtain carbon powder with the granularity of 200 meshes. Adopting a sodium hydroxide solution with the concentration of 0.8mol/L, wherein the solid-to-liquid ratio is 1: 10 leaching under the condition of ultrasonic water bath, wherein the leaching power is 6000W, the leaching time is 90min, and the temperature of the water bath is 80 ℃; the stirring speed is 2000 r/min; leaching residual fluoride and cyanide in the carbon powder, and filtering and separating after leaching to obtain filtrate and filter residue; the carbon block with fluorine removal rate up to 98% is obtained.
The surface scanning electron microscope image and the EDS energy spectrum image of the untreated waste cathode carbon block are respectively shown in figures 2 and 3, the disordered distribution of all elements but the same elements are enriched together can be obviously seen in the figures, the proportion of the carbon is higher, and the F is also obviously seen-This is also demonstrated by the EDS energy spectrum of the element, figure 3. The surface scanning electron microscope image and the EDS energy spectrum image of the waste cathode carbon block after deep fluorine removal are respectively shown in figures 4 and 5, which can obviously show that only carbon element is basically available, the rest elements are few and nearly completely removed, and the EDS energy spectrum can also obviously show that the highest peak of the carbon and the rest peaks are very small.
While the invention has been described herein with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the scope of the disclosure. More particularly, various variations and modifications are possible in the component parts or arrangements within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts or arrangements, other uses will also be apparent to those skilled in the art.
Claims (8)
1. A method for removing fluorine by the cooperation of microwave-ultrasonic wave-alkaline leaching of aluminum electrolysis waste cathode carbon blocks is characterized by comprising the following steps:
a) crushing waste cathode carbon blocks of an aluminum electrolytic cell, screening to obtain particles with the particle size of 1-3 cm, returning to the crushing step when the particle size is larger than 3cm, and entering a grinding stage when the particle size is smaller than 1 cm;
b) putting the crushed waste cathode carbon blocks into a crucible, placing the crucible in a high-temperature microwave reactor, introducing a small amount of oxygen when the temperature of the waste cathode carbon blocks is raised to 300 ℃, stopping introducing the oxygen and continuously introducing protective gas when the temperature reaches 400 ℃, and roasting the waste cathode carbon blocks at high temperature by microwave under the environment of the protective gas to physically separate cryolite and fluoride electrolyte in the carbon blocks from the cathode carbon;
c) carrying out fine grinding treatment on the cathode carbon block after microwave roasting to obtain carbon powder with the granularity of less than 100 meshes;
d) pouring the finely ground carbon powder into alkali liquor, and carrying out alkali liquor leaching treatment by ultrasonic assistance to remove residual fluoride and cyanide in the carbon powder;
e) and after leaching, separating and filtering to obtain solid materials and filtrate respectively, drying the solid materials to obtain regenerated carbon powder with the purity of over 90%, and performing evaporation separation on the filtrate for recycling.
2. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: in the microwave high-temperature roasting process in the step b), microwaves are directly acted on the waste cathode carbon blocks for high-temperature roasting, the microwave power is 1-10 kW, the microwave frequency is 2450 +/-50 or 915 +/-50 MHz, the heating rate is 30-150 ℃/min, the roasting temperature is 1000-1200 ℃, and the heat preservation time is 30-90 min.
3. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: an isolation net is arranged in the middle of the crucible used in the step b), and through holes with the diameter smaller than 0.5cm are distributed on the isolation net.
4. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 3, wherein the method comprises the following steps: the crucible is one of a corundum crucible, a quartz crucible and a mullite crucible.
5. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: the temperature measuring device adopted in the step b) is a thermocouple temperature measuring device or an infrared temperature measuring device.
6. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: the protective gas used in the step b) is at least one of argon and nitrogen.
7. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: the alkali liquor selected in the step d) is at least one of NaOH and KOH, the solution concentration is that the alkali liquor concentration is 0.4-1.2 mol/L, and the solid-liquid ratio is 1: 2 to 15.
8. The method for removing fluorine in cooperation with microwave-ultrasonic-alkaline leaching of aluminum electrolysis waste cathode carbon blocks as claimed in claim 1, wherein the method comprises the following steps: the ultrasonic power adopted in the ultrasonic-assisted alkaline leaching process in the step d) is 2-10 kW, the treatment time is 30-120 min, the water bath temperature is 50-90 ℃, and the stirring speed is 600-3000 r/min.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112941318A (en) * | 2020-12-28 | 2021-06-11 | 生态环境部南京环境科学研究所 | Horizontal oscillation type leaching equipment for leaching heavy metal in lead-zinc slag |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4410423A (en) * | 1982-03-23 | 1983-10-18 | Reynolds Metals Company | Separation of spent cathode carbon and alkaline ore |
| US4444740A (en) * | 1983-02-14 | 1984-04-24 | Atlantic Richfield Company | Method for the recovery of fluorides from spent aluminum potlining and the production of an environmentally safe waste residue |
| AU7222200A (en) * | 1999-12-17 | 2001-06-21 | Alcan International Limited | Recycling of spent pot linings |
| CN102502640A (en) * | 2011-10-28 | 2012-06-20 | 东北大学 | Method for synthetizing silicon carbide through microwave heating of pulverized fuel ash and aluminium electrolysis of waste cathode carbon blocks |
| CN105772486A (en) * | 2016-04-26 | 2016-07-20 | 中南大学 | Method for removing cyanide in waste cathode carbon in aluminum electrolysis cell |
| CN105964659A (en) * | 2016-05-27 | 2016-09-28 | 中南大学 | Comprehensive resource recycling method for waste cathode carbon blocks of aluminum cells |
| CN106077038A (en) * | 2016-06-30 | 2016-11-09 | 中南大学 | A kind of method of ultrasonic assistant flotation alkaline pressure of oxygen leaching synthetical recovery aluminum electrolysis waste cathode carbon block |
| CN106077040A (en) * | 2016-06-30 | 2016-11-09 | 中南大学 | A kind of method of ultrasonic assistant alkali leaching process aluminum electrolytic waste and old cathode carbon block |
| CN107902649A (en) * | 2017-11-28 | 2018-04-13 | 国家电投集团远达环保催化剂有限公司 | A kind of ultrasonic wave alkali leaching and the method for micro-wave digestion Combined Treatment electrolytic aluminium waste cathode carbon block |
| CN109719118A (en) * | 2019-01-04 | 2019-05-07 | 亚太环保股份有限公司 | A kind of aluminium cell solid waste recycling treatment system and method |
-
2020
- 2020-07-07 CN CN202010644698.6A patent/CN111777054B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4410423A (en) * | 1982-03-23 | 1983-10-18 | Reynolds Metals Company | Separation of spent cathode carbon and alkaline ore |
| US4444740A (en) * | 1983-02-14 | 1984-04-24 | Atlantic Richfield Company | Method for the recovery of fluorides from spent aluminum potlining and the production of an environmentally safe waste residue |
| AU7222200A (en) * | 1999-12-17 | 2001-06-21 | Alcan International Limited | Recycling of spent pot linings |
| CN102502640A (en) * | 2011-10-28 | 2012-06-20 | 东北大学 | Method for synthetizing silicon carbide through microwave heating of pulverized fuel ash and aluminium electrolysis of waste cathode carbon blocks |
| CN105772486A (en) * | 2016-04-26 | 2016-07-20 | 中南大学 | Method for removing cyanide in waste cathode carbon in aluminum electrolysis cell |
| CN105964659A (en) * | 2016-05-27 | 2016-09-28 | 中南大学 | Comprehensive resource recycling method for waste cathode carbon blocks of aluminum cells |
| CN106077038A (en) * | 2016-06-30 | 2016-11-09 | 中南大学 | A kind of method of ultrasonic assistant flotation alkaline pressure of oxygen leaching synthetical recovery aluminum electrolysis waste cathode carbon block |
| CN106077040A (en) * | 2016-06-30 | 2016-11-09 | 中南大学 | A kind of method of ultrasonic assistant alkali leaching process aluminum electrolytic waste and old cathode carbon block |
| CN107902649A (en) * | 2017-11-28 | 2018-04-13 | 国家电投集团远达环保催化剂有限公司 | A kind of ultrasonic wave alkali leaching and the method for micro-wave digestion Combined Treatment electrolytic aluminium waste cathode carbon block |
| CN109719118A (en) * | 2019-01-04 | 2019-05-07 | 亚太环保股份有限公司 | A kind of aluminium cell solid waste recycling treatment system and method |
Non-Patent Citations (3)
| Title |
|---|
| XIAO, JIN ET AL: "Comparison of ultrasound-assisted and traditional caustic leaching of spent cathode carbon (SCC) from aluminum electrolysis", 《ULTRASONICS SONOCHEMISTRY》 * |
| YUAN, JIE ET AL: "Optimization of Spent Cathode Carbon Purification Process under Ultrasonic Action Using Taguchi Method", 《INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH》 * |
| 曹晓舟 等: "铝电解槽废旧阴极炭块中有价组分的回收", 《东北大学学报(自然科学版)》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112941318A (en) * | 2020-12-28 | 2021-06-11 | 生态环境部南京环境科学研究所 | Horizontal oscillation type leaching equipment for leaching heavy metal in lead-zinc slag |
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