CN219463345U - Apparatus for treating aluminum - Google Patents
Apparatus for treating aluminum Download PDFInfo
- Publication number
- CN219463345U CN219463345U CN201990001481.4U CN201990001481U CN219463345U CN 219463345 U CN219463345 U CN 219463345U CN 201990001481 U CN201990001481 U CN 201990001481U CN 219463345 U CN219463345 U CN 219463345U
- Authority
- CN
- China
- Prior art keywords
- fluidized bed
- circulating fluidized
- calcination
- reactor
- bed reactor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 16
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 16
- 238000001354 calcination Methods 0.000 claims abstract description 49
- 239000000203 mixture Substances 0.000 claims abstract description 26
- 238000002156 mixing Methods 0.000 claims abstract description 18
- 239000004411 aluminium Substances 0.000 claims abstract description 9
- 239000007789 gas Substances 0.000 claims description 32
- 238000000034 method Methods 0.000 claims description 25
- 239000002245 particle Substances 0.000 claims description 18
- 239000008187 granular material Substances 0.000 claims description 11
- 238000011084 recovery Methods 0.000 claims description 11
- 230000003134 recirculating effect Effects 0.000 claims description 8
- 238000001816 cooling Methods 0.000 claims description 4
- 238000013461 design Methods 0.000 claims description 4
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 abstract description 14
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 abstract description 13
- 235000019738 Limestone Nutrition 0.000 abstract description 10
- 239000006028 limestone Substances 0.000 abstract description 10
- 229910000029 sodium carbonate Inorganic materials 0.000 abstract description 8
- 229910000027 potassium carbonate Inorganic materials 0.000 abstract description 7
- 238000005245 sintering Methods 0.000 description 25
- 239000000047 product Substances 0.000 description 12
- 238000005469 granulation Methods 0.000 description 11
- 230000003179 granulation Effects 0.000 description 11
- 239000012717 electrostatic precipitator Substances 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 238000005265 energy consumption Methods 0.000 description 8
- 239000011734 sodium Substances 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 239000012266 salt solution Substances 0.000 description 6
- 239000003518 caustics Substances 0.000 description 5
- 238000012546 transfer Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 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 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- 229910000323 aluminium silicate Inorganic materials 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000002585 base Substances 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 229910001570 bauxite Inorganic materials 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000008188 pellet Substances 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 238000004131 Bayer process Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052664 nepheline Inorganic materials 0.000 description 2
- 239000010434 nepheline Substances 0.000 description 2
- 238000005453 pelletization Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000008247 solid mixture Substances 0.000 description 2
- 229910004762 CaSiO Inorganic materials 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 229910000503 Na-aluminosilicate Inorganic materials 0.000 description 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- MHCAFGMQMCSRGH-UHFFFAOYSA-N aluminum;hydrate Chemical compound O.[Al] MHCAFGMQMCSRGH-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000000378 calcium silicate Substances 0.000 description 1
- 229910052918 calcium silicate Inorganic materials 0.000 description 1
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 description 1
- 238000003763 carbonization Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002817 coal dust Substances 0.000 description 1
- 238000004581 coalescence Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000000429 sodium aluminium silicate Substances 0.000 description 1
- 235000012217 sodium aluminium silicate Nutrition 0.000 description 1
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J6/00—Heat treatments such as Calcining; Fusing ; Pyrolysis
- B01J6/001—Calcining
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J6/00—Heat treatments such as Calcining; Fusing ; Pyrolysis
- B01J6/001—Calcining
- B01J6/002—Calcining using rotating drums
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/20—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/20—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium
- B01J8/22—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium gas being introduced into the liquid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/20—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium
- B01J8/22—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium gas being introduced into the liquid
- B01J8/224—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with liquid as a fluidising medium gas being introduced into the liquid the particles being subject to a circulatory movement
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
The utility model relates to an apparatus for treating aluminium, comprising at least one mixing device (20, 22, 30, 40) for mixing aluminium ore with limestone and sodium carbonate and/or potassium carbonate to obtain a mixture, and a calcination reactor (60) for producing a calcination product. A circulating fluidized bed reactor (50) is disposed between the mixing device (20, 22, 30, 40) and the calcination reactor (60), and the mixture is pre-calcined in the circulating fluidized bed reactor.
Description
Technical Field
The utility model describes an apparatus for treating aluminium comprising at least one mixing device for mixing aluminium ore with limestone and sodium and/or potassium carbonate to obtain a mixture and a calcination reactor for producing a calcination product. The utility model also relates to a corresponding method.
Background
The production of metals and their salts generally relies on heat treatment of mined ore to convert naturally occurring metal salts to the corresponding oxides and further treatment of the oxides if necessary to yield the target product.
Alumina (Al) 2 O 3 ) Bauxite is mainly used in the bayer process. Treating the mined and ground ore with sodium hydroxide at an elevated temperature of 150 ℃ to 200 ℃ to form soluble sodium metaaluminate (NaAlO) 2 ) Which precipitates as aluminum hydroxide (Al (OH)) from the supersaturated solution obtained 3 ). In the subsequent calcination step, in>Al formation at 1000 DEG C 2 O 3 。
In order for the bayer process to be economically viable, the silica content of the ore must be less than 10%. Higher levels of silica result in simultaneous dissolution of alumina and silica, forming insoluble sodium aluminosilicate in the process, which increases significantly the production of Al per ton 2 O 3 The sodium hydroxide content used thereby reduces the overall yield.
CaO/SiO during the sintering process 2 Limestone (CaCO) is added to the raw ore in a molar ratio equal to 1 3 ) At the same time will caustic ratio M 2 O/Al 2 O 3 (M + ＝K + Or Na (or) + ) Is kept at 2, so that the aluminosilicate can be treated. Typical temperatures during sintering range from 1200 ℃ to 1350 ℃ resulting in insoluble calcium silicate phases (CaSiO 3 ) Is formed by the steps of (a).
The sintering process is classified as wet, semi-wet or dry sintering depending on the moisture content of the feed. The wet sintering process for industrial use uses a slurry feed with a water content of about 30wt%. Semi-dry sintering requires pelletization of the feed with a residual water content of 10-15wt%. If the caustic ratio is equal to 2 and if only calcined limestone is to be added to adjust CaO/SiO accordingly 2 Dry sintering may be used for the ratio.
Wet sintering ensures coalescence and is therefore easy to handle. However, wet sintering has the disadvantage that the feed is viscous, resulting in high energy demands due to the additional evaporation energy. Drying, calcination and subsequent sintering must be carried out using a kiln with a long residence time, which results in high specific energy consumption of 1200-1300kcal/kg (sintered product).
On the other hand, the dry sintering process for producing alumina by nepheline sintering is the most efficient method in terms of energy consumption (650-700 kcal/kg (sintered product)). The main advantage of (most) dry processes is the pre-calcination of limestone in a flash pre-calciner prior to sintering in a rotary kiln. This allows for higher yields and shorter rotary kilns, since the main part of the calcination is not performed in the rotary kiln. However, the dry sintering process is limited to ores with a caustic ratio of 2. If the caustic ratio has to be adjusted, a low melting point carbonate (Na 2 CO 3 ：857℃，K 2 CO 3 :891℃) can cause the material to stick to the furnace walls during the sintering process, thereby failing to perform the sintering process.
A semi-dry sintering process is disclosed, for example, in CN 105540627. The method comprises the steps of uniformly mixing Bayer alkali red mud powder, lime, bauxite, sodium carbonate and coal dust to prepare raw material pellets, and sintering the raw material pellets by using two rotary kilns to obtain alumina clinker produced by a sintering method.
This semi-dry sintering approach attempts to combine the advantages of wet and dry sintering. This results in smaller kiln sizes and therefore lower energy consumption of 800-900kcal/kg (sintered product) than wet sintering. However, in order to further reduce the energy consumption of the process, it is necessary to further reduce the energy consumption, reduce the residence time and treat the low melting point base.
Disclosure of Invention
It is therefore an object of the present utility model to provide an apparatus for treating aluminosilicate ores having a high silicon content as an economically ecologically viable process.
The device proposed by the present utility model solves this task.
According to the utility model, the plant comprises at least one mixing device for mixing raw aluminium ore with limestone and sodium and/or potassium carbonate. The apparatus also includes a calcination reactor for producing a calcination product. The basic idea of the utility model is to provide a circulating fluidized bed reactor between mixing and calcination for pre-calcining the mixture.
Since the Circulating Fluidized Bed (CFB) has excellent heat and mass transfer properties, a low melting point base can be used. In addition, custom residence times may also be set. Thus, the total energy consumption can be reduced. This enables in particular the treatment of ores with a high silicon content of more than 5.5% by weight.
In the mixing step, raw aluminosilicate ore, limestone and recovered solids are combined with M 2 CO 3 (M + ＝Na + Or K + ) The aqueous solutions were mixed to adjust the caustic ratio to 2 while introducing sufficient moisture to bind all ingredients for subsequent granulation. The mixing and granulating steps may also be combined in at least one granulator. Mixing may also take part in drying or preheating. The energy intensive drying step of each carbonate has been outdated because each carbonate is introduced in the form of a salt solution.
In a preferred embodiment, the mixture obtained is granulated in two granulator in series. Particle formation will Na 2 CO 3 /K 2 CO 3 The additive is encapsulated within the particles.
These small particles greatly assist in establishing a circulating fluidized bed. In addition, less dust is generated if the material is granulated. This is demonstrated in pilot sintering tests comparing semi-dry and dry processes. In addition, the granulation not only reduces the water content, but also can integrate the dust generated in the downstream step again, thereby making the process more resource efficient.
Na added during granulation 2 CO 3 /K 2 CO 3 The solution not only provides the required base to the solid mixture, but also acts as a binder and decisively promotes the granulation process. This is demonstrated by a series of laboratory granulation experiments.
The particle size is generally between 5 and 20mm, which is most preferred for fluidized bed systems.
It is particularly preferred to use at least two granulator to fine control the final moisture content (preferably 10-13wt% water content).
With respect to the final calcination step, the type of reactor used may be a kiln. The advantage of this is that rotary kilns are a relatively inexpensive and well known technology. However, any type of fluidized bed reactor may be used to improve heat and mass transfer.
In a preferred embodiment, (Na) 2 O+K 2 O)/Al 2 O 3 R is 0.95<R<1.05 to ensure high product quality. Thus, a control unit is employed to control or regulate the amount of ore and alkali mixed in the pelletization.
Furthermore, it is particularly preferred that the sodium carbonate and/or potassium carbonate is a salt solution stored in a granulation liquid tank. Water may be mixed in to control the concentration of the solution. Thus, low saturation or supersaturated solutions may also be used. Additional energy savings can be achieved by adding (supersaturated) salt solution from the refined salt plant to the granulation tank. This saves extra evaporation energy for the salt works, corresponding to about 30 kcal per kg of sinter produced (depending on the concentration of the salt solution).
In another embodiment, at least one (preferably 2 to 3) preheating stage is provided for the mixture and/or particles. Typically, the material is heated from ambient temperature to about 200 ℃. Thus, the energy efficiency can be further improved, especially by any heat recovery concept.
Additionally or alternatively, a dryer for the mixture or particles is provided before the circulating fluidized bed reactor. Thus, the water content, preferably to a value below 1wt%, can be reduced, whereby the energy consumption can also be reduced. The granules have a very good drying performance, so that the rotary dryer is relatively short.
The mixture obtained is preferably precalcined in a circulating fluidized bed reactor at 700 to 900 ℃ (preferably 800 to 850 ℃) in order to achieve a sufficient precalcination rate. The final calcination step in the calcination reactor is generally carried out at 800 to 1400 ℃ (preferably 1000 to 1300 ℃).
The average residence time in the circulating fluidized bed reactor is between 15 and 25 minutes, preferably 20+/-2 minutes, and/or the average residence time in the calcination reactor is between 30 and 200 minutes. These residence times, especially when they are interrelated, reduce the operating temperature, avoiding the liquid portion of the base.
To further reduce the energy requirements of the plant, a first recovery line is provided for recycling the hot exhaust gases from the calcination reactor to the circulating fluidized bed reactor and/or to the at least one preheating stage. Alternatively or additionally, a second recovery line is provided for recirculating hot exhaust gases from the circulating fluidized bed reactor to the at least one preheating stage.
In order to optimize the overall energy balance to a higher level, at least one cooler is provided for cooling the calcination product formed in the calcination reactor. Preferably, a third recovery line is provided for recirculating the hot exhaust gases from the cooler to the calcination reactor and/or the circulating fluidized bed reactor and/or the at least one preheating stage.
In addition, the conduit feeds a gas having an oxygen content of between 15% and 25% by weight as fluidizing gas into the circulating fluidized bed reactor. Thus, the fluidizing gas is also used as O for chemical reactions 2 A source. Air or oxygen-enriched air is preferably used as an inexpensive oxygen source.
With respect to circulating fluidized beds, it is also preferred that the circulating fluidized bed reactor is configured such that at least 70 weight percent of the carbon contained in the ore is removed. Thus, a reduction in the total mass flow in the calcination step is achieved. In addition, the carbon combustion provides at least part of the energy required for endothermic calcination and optimal transport within the circulating fluidized bed.
The object of the utility model is thus solved by the proposed measures, which allow the treatment of aluminosilicate ores with a high silicon content on the basis of a semi-dry sintering process. The combination of the known advantages of the semi-dry based process over the existing processes is achieved at reasonable energy consumption.
According to the present utility model, there is provided an apparatus for treating aluminum comprising at least one mixing device for obtaining a mixture and a calcination reactor for producing a calcination product, wherein a circulating fluidized bed reactor is provided between the mixing device and the calcination reactor, and the mixture is pre-calcined in the circulating fluidized bed reactor;
it is characterized in that the method comprises the steps of,
a first recovery line is provided for recirculating the hot exhaust gases from the calcination reactor to the circulating fluidized bed reactor and/or to the at least one preheating stage and/or the dryer;
a second recovery line is provided for recirculating hot exhaust gases from the circulating fluidized bed reactor to the at least one preheating stage and/or the dryer.
Providing a cooler for cooling the calcination product formed in the calcination reactor;
a third recovery line is provided for recirculating the hot exhaust gases from the cooler to the calcination reactor and/or the circulating fluidized bed reactor and/or the at least one preheating stage and/or the dryer.
According to an embodiment, at least one granulator is provided for forming granules of the mixture, the granules being fed into a circulating fluidized bed reactor.
According to one embodiment, the two granulator form granules of a mixture, the granules being fed into a circulating fluidized bed reactor.
According to one embodiment, the calcination reactor is a rotary kiln.
According to an embodiment, the control unit ensures/Al 2 O 3 R is 0.95<R<1.05。
According to one embodiment, the sodium carbonate and/or potassium carbonate is a salt solution stored in a granulation liquid tank.
According to an embodiment, at least one preheating stage is provided for preheating the mixture and/or the particles.
According to an embodiment, a dryer for the mixture or particles is provided before the circulating fluidized bed reactor.
According to one embodiment, the circulating fluidized bed reactor is designed to operate at a temperature between 700 ℃ and 900 ℃.
According to an embodiment, the average residence time of the circulating fluidized bed reactor design is 15 to 25 minutes and/or the average residence time of the calcination reactor design is 30 to 200 minutes.
According to one embodiment, the conduit feeds a gas having an oxygen content of between 15% and 25% by weight as fluidizing gas into the circulating fluidized bed reactor.
According to an embodiment, the circulating fluidized bed reactor is configured such that at least 70 weight percent of the carbon contained in the ore is removed.
The utility model further relates to a method. The method comprises the following steps: (a) Mixing aluminium ore with limestone and sodium and/or potassium carbonate to obtain a mixture; (b) calcining the mixture to a calcined product. As an important step, the mixture is pre-calcined in a circulating fluidized bed between step (a) and step (b).
Preferably, the moisture content of the mixture or particles introduced in the pre-calcination is 10 to 15% by weight, which provides good stability of the particles.
Furthermore, in the preferred embodiment of the precalcination, at least 70 weight percent of the carbon contained in the ore is removed to reduce the total mass flow.
Drawings
Other features, advantages and possible applications of the present utility model will become apparent from the following description of the drawings and exemplary embodiments. All the features described and/or illustrated constitute the subject matter of the utility model as such or in any combination, irrespective of whether they are contained in the claims or in the reverse.
In the figure:
fig. 1 schematically shows the apparatus of the present utility model.
Detailed Description
Fig. 1 shows the main structure of the device according to the utility model. Bauxite ore is fed through conduit 10 into a homogenizing silo 11 where it is mixed with recycled solids and/or limestone fed through conduits 13 and 14 to form a mixture.
Conduit 15 feeds at least one granulation tank with a saline solution consisting of sodium carbonate and potassium carbonate, which may be diluted if necessary by injecting water through conduit 16.
The mixture and the formulated salt solution are then dosed via conduits 17 and 18 into a first granulator 20, in which three tasks are achieved: adding a desired amount of alkali to the solid mixture of limestone, nepheline and dust (and optionally some material recovered from the process); providing water for granulation; and acts as an adhesive. In the present embodiment, the first granulator 20 is also used as a mixing device. However, it is also contemplated that a mixer may be added prior to the first granulator 20. It is highly desirable, but not necessary, to have a second granulator 22, preferably connected in series by a conduit 21, to achieve the necessary granulation time and better control of the final moisture. In this case, additional water may be added through conduit 24.
Downstream of the first granulator 20 and the second granulator 22, the granules produced are fed into a dryer 30 through a conduit 23. In the dryer, the wet particles are typically dried with hot flue gas from conduit 63. Preferably, the dryer 30 is designed as a rotary dryer.
The exhaust gases are conveyed via a conduit 32 to an electrostatic precipitator 33 and from there via a conduit 35 to an exhaust gas treatment, not shown. The small particles filtered in the electrostatic precipitator 33 are fed through conduit 34 into conduit 45 for recovery.
The dried pellets are fed through conduit 31 into a preheating section 40. Preferably, the preheating section 40 comprises 2 or 3 stages. Furthermore, the subsequent investment/cyclone stage leads to particularly good results. To improve the energy concept, hot gas fed in through conduit 53 may be used, preferably counter-current feed.
From the preheating stage 40, the exhaust gases are fed via a conduit 42 to an electrostatic precipitator 43. Part of the exhaust gases from the electrostatic precipitator 43 is preferably discharged as exhaust gases via conduits 46 and 48, while another part of the exhaust gases is conveyed as gases for carbonization via conduits 46 and 47. The filtered granules may be fed into the first granulator 20 via conduits 44 and 45.
After preheating, the particles are fed via conduit 41 into a circulating fluidized bed reactor 50 for pre-calcination, in order to ensure the necessary very good heat and mass transfer according to the utility model. In a circulating fluidized bed reactor, the particles are decarbonized to a degree of at least 80wt%. The pre-calcined particles are fed into the calcination reactor 60 through conduit 51. Fluidizing gas is injected through the bottom nozzle grid via conduits 78 and/or 52. Preferably about 20vol% of the fluidizing gas is fresh air, wherein this percentage of fresh air may deviate depending on the design of the circulating fluidized bed. Preferably, a larger portion of the fluidizing gas is air which is conveyed from the downstream apparatus through conduits 76, 78 (i.e. so-called tertiary air pipes) to the circulating fluidized bed reactor (i.e. the precalcination reactor).
In addition, hot exhaust gases from a circulating fluidized bed with a large amount of exhaust gases can be conveyed via a conduit 53 to the preheating section 40. In the preheating section, these off-gases can be used as direct and/or indirect heat transfer medium. Thus, no separate exhaust gas treatment is required either.
The final sintering is carried out in a calcination reactor 60, preferably designed as a rotary kiln, which reduces the amount of hot gas compared to fluidized bed technology. Fresh air is fed into the calcination reactor via conduit 62 while hot gas can also be introduced from a downstream cooler via conduits 76 and 77 to reduce the energy to be supplied.
The hot sinter thus produced is conveyed via a conduit 61 into a cooler 70, in which the hot sinter is preferably air-cooled by a grate cooler. The cooler 70 is preferably cooled by air fed through a conduit 73. This air is withdrawn and used at least in part as a heat transfer medium in the circulating fluidized bed reactor (i.e., pre-calcination reactor) 50 and the calcination reactor 60. In addition, air may be drawn into an electrostatic precipitator 75 via a duct 74 and from the electrostatic precipitator to an off-gas treatment, not shown, via a duct 76.
The cooled product is removed via the ducts 71, 72 and can thus be mixed with small particles filtered out in the electrostatic precipitator 75.
Reference numerals
10. Catheter tube
11. Homogenizing silo
12. Granulating liquid tank
13-18 catheter
20. First granulator
21. Catheter tube
22. Second granulator
23 24 catheter
30. Dryer
31 32 catheter
33. Electrostatic precipitator
34 35 conduit
40. Preheating section
41 42 conduit
43. Electrostatic precipitator
44-48 catheter
50. Circulating fluidized bed reactor
51. Catheter tube
60. Calcination reactor
61 62 conduit
70. Cooling device
71-74 catheter
75. Electrostatic precipitator
76 77 catheters.
Claims (7)
1. An apparatus for treating aluminum, comprising at least one mixing device for obtaining a mixture and a calcination reactor (60) for producing a calcination product, wherein a circulating fluidized bed reactor (50) is arranged between the mixing device and the calcination reactor (60) and the mixture is pre-calcined in the circulating fluidized bed reactor;
it is characterized in that the method comprises the steps of,
a first recovery line is provided for recirculating hot exhaust gases from the calcination reactor (60) to the circulating fluidized bed reactor (50) and/or at least one preheating stage and/or dryer (30);
a second recovery line is provided for recirculating hot exhaust gases from the circulating fluidized bed reactor (50) to the at least one preheating stage and/or dryer (30);
-providing a cooler (70) for cooling the calcination product formed in the calcination reactor (60);
a third recovery line is provided for recirculating the hot exhaust gases from the cooler (70) to the calcination reactor (60) and/or the circulating fluidized bed reactor (50) and/or the at least one preheating stage and/or the dryer (30).
2. An apparatus for treating aluminium according to claim 1, characterized in that at least one granulator is provided for forming granules of the mixture, the granules being fed into a circulating fluidized bed reactor (50).
3. The apparatus for treating aluminum according to claim 1 or 2, characterized in that two granulator form granules of a mixture, the granules being fed into a circulating fluidized bed reactor (50).
4. The apparatus for treating aluminum according to claim 1 or 2, wherein the calcination reactor (60) is a rotary kiln.
5. An apparatus for treating aluminium according to claim 1 or 2, wherein at least one preheating stage is provided for preheating the mixture and/or particles.
6. The apparatus for treating aluminum according to claim 1 or 2, characterized in that a dryer (30) for the mixture or particles is provided before the circulating fluidized bed reactor (50).
7. The plant for treating aluminium according to claim 1 or 2, characterized in that the design operating temperature of the circulating fluidized bed reactor (50) is between 700 ℃ and 900 ℃.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP2019/082626 WO2021104613A1 (en) | 2019-11-26 | 2019-11-26 | Optimized semi-dry process for sintering of aluminosilicates in the production of alumina |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219463345U true CN219463345U (en) | 2023-08-04 |
Family
ID=68699458
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201990001481.4U Active CN219463345U (en) | 2019-11-26 | 2019-11-26 | Apparatus for treating aluminum |
Country Status (4)
| Country | Link |
|---|---|
| CN (1) | CN219463345U (en) |
| BR (1) | BR212022010130U2 (en) |
| DK (1) | DK202200048Y3 (en) |
| WO (1) | WO2021104613A1 (en) |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10260739B3 (en) * | 2002-12-23 | 2004-09-16 | Outokumpu Oy | Process and plant for producing metal oxide from metal compounds |
| US9272912B2 (en) * | 2006-08-25 | 2016-03-01 | Robert A. Rossi | Process and system for producing commercial quality carbon dioxide from recausticizing process calcium carbonates |
| DE102007014435B4 (en) * | 2007-03-22 | 2014-03-27 | Outotec Oyj | Process and plant for the production of metal oxide from metal salts |
| DE102009006095B4 (en) * | 2009-01-26 | 2019-01-03 | Outotec Oyj | Process and plant for the production of aluminum oxide from aluminum hydroxide |
| US8728428B1 (en) * | 2013-03-13 | 2014-05-20 | Carbon Engineering Limited Partnership | Recovering a caustic solution via calcium carbonate crystal aggregates |
| DE102015108722A1 (en) * | 2015-06-02 | 2016-12-08 | Outotec (Finland) Oy | Process and plant for the thermal treatment of granular solids |
| CN104843751B (en) * | 2015-06-10 | 2016-05-18 | 沈阳鑫博工业技术股份有限公司 | A kind of bauxite activation burning low temperature digestion series and activation burning and dissolving-out method |
| CN105540627A (en) | 2016-01-19 | 2016-05-04 | 中国铝业股份有限公司 | Preparation method for clinker of alumina produced by sintering process |
| CN107935005B (en) * | 2016-10-12 | 2019-09-10 | 北京矿冶研究总院 | Method for pretreating fly ash carbonate solution and extracting alumina |
-
2019
- 2019-11-26 CN CN201990001481.4U patent/CN219463345U/en active Active
- 2019-11-26 WO PCT/EP2019/082626 patent/WO2021104613A1/en active Application Filing
- 2019-11-26 BR BR212022010130U patent/BR212022010130U2/en unknown
-
2022
- 2022-06-23 DK DKBA202200048U patent/DK202200048Y3/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| DK202200048U1 (en) | 2022-07-01 |
| DK202200048Y3 (en) | 2022-08-12 |
| BR212022010130U2 (en) | 2022-07-12 |
| WO2021104613A1 (en) | 2021-06-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104555946B (en) | Method for jointly producing sulphuric acid and cement clinker by using sulphur gas to reduce gypsum | |
| US5049198A (en) | Calcium sulfate process for the coproduction of Portland cement clinker and concentrated sulfur dioxide adequate to manufacture sulfuric acid | |
| US8460624B2 (en) | Process and plant for producing metal oxide from metal salts | |
| CN107056102B (en) | System and method for producing sulphoaluminate cement and co-producing sulfur by utilizing desulfurized gypsum and aluminum ash | |
| US8313715B2 (en) | Process and plant for producing metal oxide from metal salts | |
| CN112694067A (en) | Production method for co-producing cement and sulfuric acid by using phosphogypsum | |
| CN101955166B (en) | Method for decomposing semi-hydrated phosphogypsum | |
| CN114853369A (en) | Method and apparatus for preparing calcined compound for producing calcined product | |
| CN102502524A (en) | Method for producing sulfur dioxide from calcium sulfate and sulfur | |
| CN101481222B (en) | Method for preparing sulphoaluminate cement by-product ammonia sulfate by partly converting phosphogypsum | |
| CN103964715A (en) | Energy-saving and cost-reducingmethod for producingcementfromgypsumwith by-product ofsulfuric acid | |
| CN112551925A (en) | Device and method for comprehensively utilizing gypsum raw material | |
| CN103276195B (en) | Stone coal vanadium ore shaft roasting method and system | |
| CN103764562B (en) | γ-2CaOSiO 2manufacture method | |
| CN219463345U (en) | Apparatus for treating aluminum | |
| US6569793B2 (en) | Fluidized reaction of synthetic silicates | |
| AU2022100082B4 (en) | Optimized semi-dry process for sintering of aluminosilicates in the production of alumina | |
| WO2002018270A1 (en) | A method of decomposing gypsum to sulfur dioxide and the apparatus thereof | |
| CN104609451B (en) | Process for preparing aluminum oxide by virtue of dry-sintering method | |
| CN103922623B (en) | The sinter leaching system being calcareous raw material with dry carbide slag | |
| CN204508809U (en) | By the device of sulfur gas reduction gypsum Sulphuric acid jointly producing cement grog | |
| AU2021211083B2 (en) | Thermal treatment of mineral raw materials using a mechanical fluidised bed reactor | |
| CN102653394A (en) | Technology for reducing plaster and generating SO2 and CaO by using coal in multistage multi-atmosphere fluidized bed | |
| KR20050113529A (en) | Method and apparatus for manufacturing lime using the fluidized bed firing furnace | |
| JPS5884150A (en) | Method and device for baking cement raw material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20240527 Address after: Espoo, Finland Patentee after: Meizhuo Metal Co.,Ltd. Country or region after: Finland Address before: Tampere Patentee before: Medtronics Finland Ltd. Country or region before: Finland |
|
| TR01 | Transfer of patent right |