CN1160019A - Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore - Google Patents
Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore Download PDFInfo
- Publication number
- CN1160019A CN1160019A CN 97100772 CN97100772A CN1160019A CN 1160019 A CN1160019 A CN 1160019A CN 97100772 CN97100772 CN 97100772 CN 97100772 A CN97100772 A CN 97100772A CN 1160019 A CN1160019 A CN 1160019A
- Authority
- CN
- China
- Prior art keywords
- ore
- alumina
- ammonium sulfate
- aluminum
- solution
- 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.)
- Granted
Links
Images
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Abstract
A process for extracting alumina from low-grade aluminium ore includes crushing ore, screening, activating calcining, mixing with ammonium sulfate for solid reaction, leaching resultant in water, separation of solid from liquid, dissociation in ammonia water, removing Fe, separation, refining to obtain aluminium hydroxide, and calcining to obtain alumina. Its advantages are high leaching rate of alumina (more than 90%), reuse of ammonium sulfate, and no corrosion of equipment and environmental pollution.
Description
The invention relates to a chemical extraction metallurgical process, in particular to a process method for extracting aluminum oxide from low-grade aluminum-containing ores by a non-alkaline method to finally produce aluminum hydroxide and aluminum oxide products.
The existing alumina production process completely adopts an alkaline process such as a Bayer process, a sintering process or a combination process, and the alkaline process relates to a more complex desiliconization process, so that the alumina content in the ore processed by the process requirement is high (more than 50-60 percent), and the silica content is low (for example, the aluminum-silicon ratio required by the Bayer process is more than 7-8), thereby limiting the possibility of producing alumina by using the alkaline process for low-grade high-silicon aluminum ore.
Obviously, the alumina is produced by adopting the alkaline process, the alumina cannot be extracted by utilizing low-grade high-silicon aluminum vanadium soil, alunite ore, kaolin and the like which are abundant in reserves in China, and the alkaline process also has desiliconization operation at high temperature and high pressure, so that certain difficulty is increased in production operation and the cost is increased.
In order to innovate the alkaline process, many people have carried out research and development on the acid process. As in document (1): U.S. patent publication No. 4,124,680(1978.11.7) entitled: "method for obtaining pure alumina by acid leaching of high-alumina ores containing other elements". [ U.S. Pat. No. 4,124,680(1978) in a Method of organizing pure aluminum by acid attach on aluminum minerals contained other elements]. (2) The journal of metals 1962, 121-: "extraction of Alumina with acid" (Journal of Metals 1962: 121-.
The acid process is to treat the aluminum ore with inorganic acid (such as sulfuric acid, hydrochloric acid, etc.) to react alumina in the ore with acid to produce aluminum salt, and the impurities of ferrotitanium in the ore will produce corresponding salt to enter the extracting solution together with the aluminum salt, while the silica in the ore is almost completely remained in insoluble slag due to insolubility of acid. Removing impurities (mainly iron) in the aluminum salt solution, and performing post-treatment and calcination to obtain the aluminum oxide for metallurgy, wherein an acid process flow is illustrated in figure 1.
Compared with the alkaline process, the acid process has the main characteristics that:
A. does not need to carry out complex desiliconization process operation, thereby being suitable for processing high-silicon bauxite and having larger raw material adaptability than an alkaline method.
B. Because the iron content in the aluminum ore is far less than that of silicon, the impurity removal amount of aluminum salt is less, the material flow, the power and the heat energy consumption in the production flow are reduced, and the complexity and the operation of equipment are less or more convenient than those of an alkaline method, so that the equipment investment and the operation cost can be saved.
C. Because the acid is adopted to dissolve the ore, the corrosion problem of the acid to production equipment and the environmental pollution problem are prominent.
D. The removal of iron impurities from alumina is difficult.
E. The intermediate product of the acid method production process is aluminum salt with extremely low aluminum content, if the aluminum salt is decomposed into aluminum oxide by a direct roasting method, a large amount of heat energy is consumed, and acid radicals are not easy to recover; if other methods of dissociating aluminum salts are used, a large amount of by-products are generated. These all make the acid process economically difficult to be realized and the acid process has not been realized industrially so far.
The invention aims to overcome the defects of the alkaline process and the acid process, to extract alumina from various low-grade (the content of the alumina is less than 40 percent) bauxite, to overcome the restrictive requirement of the alkaline process on the content of silicon in the bauxite, and to fully utilize the low-grade bauxite resources in China, the second aim of the invention is to treat the bauxite by adopting non-acid and non-alkaline raw materials, to overcome the defectsof serious corrosion of the original process (particularly the acid process) on production equipment and environmental pollution, and the third aim of the invention is to dissolve the bauxite by utilizing one ammonium sulfate which can be recycled, so that the process can reduce the consumption of the raw materials to the minimum, does not form byproducts, and can be economically established, and the fourth aim of the invention is to improve the dissolution rate of the alumina.
The object of the present invention is achieved by (1) the basic principle of the ammonium sulfate process of the present invention can be expressed by the following reaction formula ① ② ③ ④ ⑤ (2) The basic process of the ammonium sulfate method comprises the following steps:
firstly, crushing and screening aluminum-containing ores, and taking mineral powder with the granularity of 100-300 meshes as a production raw material;
secondly, activating and roasting, wherein the mineral powder is activated and roasted for 1-3 hours at 500-700 ℃, so that alumina in the ore is activated, and the dissolution rate of the alumina can be greatly improved; the process of the invention adopts the ore roasting process, which destroys the bonding force between the aluminum-containing oxide and other components in the bauxite, so that the alumina in the ore is in a dispersed state, has a larger action surface and high chemical activity, thereby greatly improving the dissolution rate of the alumina;
and thirdly, carrying out solid-phase dissolution reaction, mixing the roasted mineral powder and ammonium sulfate according to the molar ratio of ammonium sulfate to alumina in the ore of 6-10, carrying out solid-phase reaction at 350-450 ℃, recovering ammonia in tail gas generated by the reaction by an absorption method, and removing a small amount of possibly generated waste gas to avoid environmental pollution. The solid phase reaction is directly carried out between ammonium sulfate and ore, and the silicon oxide in the ore is remained in the slag because of not reacting with ammonium sulfate, so that the silicon oxide can be separated during leaching and filtering. Ferric sulfate generated by the action of ferric oxide and ammonium sulfate can be separated when the aluminum ammonium vanadium is crystallized, or the iron is removed by alkali dissolution in the subsequent process, thereby ensuring the quality indexes of aluminum hydroxide and aluminum oxide, in particular the limit of metallurgical aluminum oxide on the content of iron and silicon. The invention optimizes the optimal reaction operation conditions, in particular to the rule of the influence of the ore granularity on the reaction conversion rate (the dissolution rate of alumina). The process is a key step which is different from the prior alkaline method and acid method processes.
And fourthly, stirring and leaching the reaction product with water at 70-100 ℃ for 0.5-1 hour, and then carrying out solid-liquid separation (the slag can be used as a raw material for comprehensive utilization after being washed). The reaction product is directly leached by water without using acid or other leaching agent with any concentration, so that the process operation is simple and easy. This process, coupled with the filtration step, allows the silica in the ore to be separated from the system. Because the aluminum and the iron are separated, the comprehensive utilization of the silicon slag is facilitated;
fifthly, dissociating the leaching solution at normal temperature and normal pressure by adopting ammonia water, wherein the reaction formula is Thereby obtaining aluminum hydroxide precipitate. Filtering and separating the precipitate and the solution, feeding the filtrate into the concentration and crystallization processes to prepare ammonium sulfate for recycling, and further refining the aluminum hydroxide precipitate. The amount of ammonia water added in the ammonolysis operation is calculated according to the stoichiometric formula and then is excessive, the ammonia excess coefficient is 1.05-1.5, and the mixture is stirred for 20 percent30 minutes.
Sixthly, carrying out alkali dissolution iron removal on the aluminum hydroxide precipitate by adopting a NaoH solution and a causticizing solution, wherein the concentration of alkali liquor is [ Na]2O]130-160 g/L or causticization coefficient αCaustic soda1.6-2.0 at 60-90 deg.CStirring for 60-80 minutes. Removing iron and then Fe (OH)3The precipitate is separated from the sodium aluminate solution by filtration. The iron can be effectively removed by the alkali solvent, so that the quality of aluminum hydroxide and aluminum oxide is ensured;
and seventhly, decomposing the sodium aluminate solution to obtain an aluminum hydroxide product, and further calcining the aluminum hydroxide product to obtain an aluminum oxide product. The decomposition and calcination operations are typically conducted using bayer process conditions.
The invention has the following effects:
(1) the process method of the invention adopts the ammonium sulfate to react with the alumina in the ore, and because the ammonium sulfate does not react with the silica, the subsequent procedures do not need desiliconization operation, thereby being suitable for treating variouslow-grade aluminum-containing ores with very low aluminum-silicon ratio; and because the activation roasting process and the solid-phase dissolution reaction are adopted, the dissolution rate of alumina in the ore can reach more than 90 percent.
(2) The method for adjusting the pH value of the alkaline solution is adopted by the iron removal process, which is different from a repeated recrystallization purification method, so that the iron removal is more effective, the product quality is ensured, and the composition of the alumina product prepared from the low-grade bauxite is as follows:
Al2O3Fe2O3SiO2TiO2MgO
99.87 0.012 0.039 0.053 0.018 wt％
(3) the invention solves the technical problem that the dissolution rate of the alumina is more than 90 percent by using the process method of extracting the alumina from the low-grade aluminum ore by using the ammonium sulfate, thereby fully utilizing the low-grade alumyte, the gangue, the alunite, the clay and other aluminum-containing ores which are abundant in China;
(4) the method has no environmental pollution problem and no corrosion to equipment;
(5) the ammonium sulfate raw material can be recycled, so that the consumption of the raw material is greatly reduced, and byproducts are not formed.
The invention is explained in more detail below with reference to exemplary embodiments and the accompanying drawings:
FIG. 1 is a process flow diagram of acid extraction of alumina
FIG. 2 is a process flow diagram of the present invention
Example 1
The Shandong Zibo bauxite ore is used as a raw material, and the ore comprises the following components:
Al2O3SiO2CaO MgO Fe2O3TiO2MaO2burn and relieve
55.92 23.18 1.20 0.22 1.37 2.13 0.022 14.43wt％
Roasting the ore with the granularity of 100-200 meshes at 550-650 ℃ for 1-3 hours; then the ore is mixed with sulfurMixing ammonium sulfate and alumina in the ore according to the molar ratio of 6-10, and reacting at 350 ℃ for 4 hours; the reactant is stirred and leached for 1 hour at the temperature of 90 ℃, then the solid-liquid separation is carried out, the leaching solution is aminolyzed, the amount of added ammonia is calculated according to the stoichiometric formula, then the material is added with the ammonia excess coefficient of 1.05, and the stirring is carried out for 20 minutes at the normal temperature and the normal pressure, thus obtaining the aluminum hydroxide precipitate. Then the concentration of alkali liquor is Na2]130g/L or causticization factor αCaustic sodaStirring the mixture at the temperature of 60-90 ℃ for 60 minutes to remove iron, and separating and calcining the mixture after removing the iron according to a common Bayer process. The dissolution rate of alumina in the ore is more than 90 percent and can reach 96 percent. The product index is the same as the invention effect (1). Example 2
Adopts Yangquan low-grade bauxite (three-grade) as raw material, and its composition is
Al2O3SiO2Fe2O3
47.76 30.21 1.53wt％
Roasting the ore with the granularity of 200-300 meshes at 650-700 ℃ for 1-2 hours; then mixing the ore and ammonium sulfate according to the mol ratio of 6 of ammonium sulfate to alumina in the ore, reacting for 2-4 hours at 400 ℃, stirring and leaching reactants for 1 hour at 80-90 ℃ by using water, and carrying out the rest conditions according to the embodiment 1, wherein the dissolution rate of the alumina in the ore is 89.70-95.22%. Example 3
Adopts Yangquan Guzhuang coal gangue as raw material, and its composition is
Al2O3SiO2Fe2O3CaO MgO SO3
26.43 54.01 6.34 1.94 0.6 1.09wt％
The granularity of the ore is 200-300 meshes, and the ore is activated and roasted for 1 hour at 650 ℃; then mixing the ore and ammonium sulfate according to the molar ratio of 8 of ammonium sulfate to aluminum oxide in the ore, and reacting for 3-5 hours at 350 ℃; stirring and leaching the reaction product for 1 hour at the temperature of 80-90 ℃, and carrying out other operation processes according to the embodiment. The dissolution rate of alumina in the ore reaches 95.04-96.67%.
Claims (2)
1. A method for extracting ammonium sulfate of alumina from low-grade aluminum-containing ore is characterized by comprising the following steps:
the first step is as follows: firstly, crushing and screening aluminum-containing ores, and taking mineral powder with the granularity of 100-300 meshes as a production raw material;
the second step is activating roasting: activating and roasting the mineral powder at 500-700 ℃ for 1-3 hours;
the third step is solid phase dissolution reaction: mixing the activated mineral powder and ammonium sulfate according to the molar ratio of ammonium sulfate to alumina in the ore of 6-10, and carrying out solid phase reaction at 350-450 ℃; which is of the formula ；
The fourth step: stirring and leaching the reaction product with water at 70-100 ℃ for 0.5-1 hour, and then carrying out solid-liquid separation;
the fifth step: dissociating the separated leaching solution at normal temperature and pressure by using ammonia water, adding the ammonia water, stirring for 20-30 minutes, wherein the reaction formula is Dissociation yields 2Al (OH)3Filtering and separating the precipitate and the solution;
a sixth step: the aluminum hydroxide precipitate adopts a concentration of [ Na]2O]130-160 g/L sodium hydroxide solution or αCaustic sodaCarrying out alkali-soluble iron removal on the causticized solution of 1.6-2.0 under the operation condition of stirring at the temperature of 60-90 ℃ for 60-80 minutes. The reaction formula is as follows: after iron removal, Fe (OH)3Filtering and separating the precipitate and the sodium aluminate solution;
a seventh step of: the sodium aluminate solution is decomposed and calcined according to the normal Bayer process.
2. A process according to claim 1 for the extraction of ammonium sulphate from low grade aluminium bearing ores, characterised in that: the leaching solution is dissociated by ammonia water at normal temperature and normal pressure, and the reaction formula is as follows: the ammonia water amount is calculatedaccording to a stoichiometric formula and then is excessive, and the ammonia excess coefficient is 1.05-1.5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN97100772A CN1054108C (en) | 1997-02-25 | 1997-02-25 | Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN97100772A CN1054108C (en) | 1997-02-25 | 1997-02-25 | Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1160019A true CN1160019A (en) | 1997-09-24 |
| CN1054108C CN1054108C (en) | 2000-07-05 |
Family
ID=5165306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN97100772A Expired - Fee Related CN1054108C (en) | 1997-02-25 | 1997-02-25 | Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1054108C (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1321064C (en) * | 2005-07-18 | 2007-06-13 | 贵阳铝镁设计研究院 | Bayer process of cauticizing barium salt in mother liquid |
| CN101734698B (en) * | 2009-09-08 | 2013-01-09 | 东北大学 | Method for preparing aluminum oxide from aluminiferous material |
| CN103910370A (en) * | 2014-04-01 | 2014-07-09 | 沈阳化工大学 | Method for extracting aluminum hydroxide from coal ash by virtue of ammonium salt dissolving and ammonia circulating process |
| CN104556175A (en) * | 2015-01-22 | 2015-04-29 | 武汉理工大学 | Method for preparing aluminum hydroxide from potash feldspar decomposition tailings |
| CN106986369A (en) * | 2017-04-08 | 2017-07-28 | 广西凤山县五福矿业发展有限公司 | The method that gypsum is prepared during low iron aluminium concentrate synthetical recovery |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES482881A1 (en) * | 1979-07-27 | 1980-04-01 | Consejo Superior Investigacion | A method of obtaining alumina from clay and other alumino-silicates and alumina obtained by this method. |
| CN1072656A (en) * | 1991-11-26 | 1993-06-02 | 兰州大学 | The production method of aluminium hydroxide |
| CN1035505C (en) * | 1991-12-06 | 1997-07-30 | 兰州工业资源技术研究所 | Process for prodn. of alumina by combined acid-salt method |
-
1997
- 1997-02-25 CN CN97100772A patent/CN1054108C/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1321064C (en) * | 2005-07-18 | 2007-06-13 | 贵阳铝镁设计研究院 | Bayer process of cauticizing barium salt in mother liquid |
| CN101734698B (en) * | 2009-09-08 | 2013-01-09 | 东北大学 | Method for preparing aluminum oxide from aluminiferous material |
| CN103910370A (en) * | 2014-04-01 | 2014-07-09 | 沈阳化工大学 | Method for extracting aluminum hydroxide from coal ash by virtue of ammonium salt dissolving and ammonia circulating process |
| CN103910370B (en) * | 2014-04-01 | 2015-12-09 | 沈阳化工大学 | A kind of ammonium salt dissolving and circulation ammonia process extract the method for aluminium hydroxide from flyash |
| CN104556175A (en) * | 2015-01-22 | 2015-04-29 | 武汉理工大学 | Method for preparing aluminum hydroxide from potash feldspar decomposition tailings |
| CN104556175B (en) * | 2015-01-22 | 2016-08-24 | 武汉理工大学 | The method of preparing hydrogen aluminium oxide from potassium feldspar decomposition tailings |
| CN106986369A (en) * | 2017-04-08 | 2017-07-28 | 广西凤山县五福矿业发展有限公司 | The method that gypsum is prepared during low iron aluminium concentrate synthetical recovery |
| CN106986369B (en) * | 2017-04-08 | 2018-07-06 | 广西凤山县五福矿业发展有限公司 | The method that gypsum is prepared during low iron aluminium concentrate synthetical recovery |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1054108C (en) | 2000-07-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhong et al. | Extraction of alumina and sodium oxide from red mud by a mild hydro-chemical process | |
| CN109112293B (en) | Method for selectively enriching scandium from Bayer process red mud | |
| CN101863500B (en) | Method for producing alumina with aluminum-containing metallurgical material | |
| CN1865460A (en) | Method for extracting vanadium,molybdenum,nickel,cobalt,aluminium from waste aluminium base catalyst | |
| CN101760651A (en) | Process for extracting vanadium by acid leaching of stone coal | |
| CN101058852A (en) | Multistage counter current acid leaching process containing nickel serpentine ore | |
| CN108892146B (en) | Desiliconization method of silicon-aluminum-containing material | |
| CN109336147B (en) | Method for producing alumina by using industrial solid waste rich in alumina | |
| CA3165132A1 (en) | A process for producing alumina and a lithium salt | |
| CN111792650A (en) | Full-element recycling process of coal ash or coal gangue by hot-melt salt method | |
| CN112875733A (en) | Method for preparing nano-scale magnesium hydroxide by extracting magnesium from black talc ore | |
| CN103663516B (en) | A kind of method utilizing aluminous fly-ash to prepare aluminium hydroxide | |
| CN1824607A (en) | Vanadium extraction technology of high aluminium slag | |
| CN111041204B (en) | Comprehensive utilization method of magnesium and/or calcium-containing waste liquid in rare earth smelting separation process | |
| CN1257292C (en) | Method for recovering nickel and aluminum from waste aluminum based nickel-containing catalyst | |
| CN1160019A (en) | Ammonium sulfate method for extracting alumina from low-grade aluminium-contg. ore | |
| CN117049490A (en) | Method for preparing iron phosphate and co-producing silicon-aluminum composite filler from Bayer process red mud | |
| CN112939094B (en) | Method for preparing nano cobalt tungstate and recovering crude titanium slag | |
| CN1237539A (en) | Method for recovering rare earth carbonate by bastnaesite decomposition through ammonium chloride baking process | |
| CN113149048B (en) | Method for treating sodium oxalate solid waste residues in alumina production process | |
| US3436176A (en) | Process of producing high purity alumina from aluminum-bearing,acidic,sulfate solutions | |
| CN115072749A (en) | Method for extracting lithium from spodumene without slag | |
| CN112813284A (en) | Method for extracting aluminum from aluminum-containing mineral | |
| WO1991009978A1 (en) | Process for converting dross residues to useful products | |
| CN114477249B (en) | Method for preparing high-purity magnesium hydroxide and calcium sulfate by adopting calcium carbide furnace purification ash |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |