CN113802149B - Method for extracting metallic iron from zinc kiln slag - Google Patents
Method for extracting metallic iron from zinc kiln slag Download PDFInfo
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- CN113802149B CN113802149B CN202110919176.7A CN202110919176A CN113802149B CN 113802149 B CN113802149 B CN 113802149B CN 202110919176 A CN202110919176 A CN 202110919176A CN 113802149 B CN113802149 B CN 113802149B
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- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/34—Electrolytic production, recovery or refining of metals by electrolysis of melts of metals not provided for in groups C25C3/02 - C25C3/32
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Abstract
The invention discloses a method for extracting metallic iron from zinc kiln slag, which comprises the steps of taking zinc kiln slag and a graphite rod as a cathode electrode and an anode electrode respectively, inserting the zinc kiln slag and the graphite rod into a molten salt system formed by mixing and melting sodium chloride and potassium chloride in a protective gas atmosphere, carrying out molten salt constant-tank pressure electrolysis reaction, and finally cleaning and drying the cathode electrode to obtain the metallic iron. The method has the advantages of simple operation, concise flow, high recovery rate of the metallic iron, low energy consumption and less pollutant discharge, is suitable for industrial production, and solves the problems of low extraction rate and high extraction difficulty caused by complex zinc kiln slag system in the traditional process. The method is suitable for extracting the metallic iron from the zinc kiln slag.
Description
Technical Field
The invention belongs to the technical field of metallurgical engineering, and relates to zinc kiln slag, in particular to a method for extracting metallic iron from zinc kiln slag.
Background
The zinc kiln slag is a residue produced by adding a certain amount of coke into leaching slag (zinc tailings) produced by zinc ore after zinc hydrometallurgy, and recovering metals such as zinc, lead and the like through high-temperature reduction in a rotary kiln. At present, most of zinc kiln slag in China is piled up in a smelting plant because the zinc kiln slag is not reasonably utilized. With the importance of the nation on the environmental protection, the treatment method not only occupies a large amount of land resources, but also can easily migrate or infiltrate into the ground along with rainwater and cause great damage to the environment. The main chemical components of the zinc kiln slag are iron oxide, silicon dioxide, calcium oxide, aluminum oxide and the like, and the main chemical components and the contents are shown in the following table:
it is found that a large amount of metallic iron still exists in the zinc kiln slag.
At present, zinc kiln slag is usually sold to cement plants at a lower price to be used as ingredients, so that valuable metals are not recycled to cause low utilization efficiency, and the zinc kiln slag belongs to low added value utilization. Because coke or various reagents are added in the treatment process of the zinc tailings to extract the metal zinc, the content of valuable metals in the generated zinc kiln slag is greatly reduced, meanwhile, a zinc kiln slag system becomes more complex, and the factors greatly improve the difficulty of recovery work of the valuable metals in the zinc kiln slag.
The traditional process has the following treatment modes for zinc kiln slag:
(1) Mineral separation method: the best process flow is a flotation-magnetic separation-flotation full open circuit test, the recovery of Ag in the flow is better, but the granularity requirements in the two flotation process flows are different, and the grinding treatment must be carried out separately. The zinc kiln slag is treated by floatation-magnetic separation technology, firstly, the flotation is adopted to recover carbon preferentially, then the tailings after flotation are subjected to magnetic separation to recover iron, and the result shows that the recovery rate of the carbon and the iron respectively reaches 85.60% and 68.24%, so that the zinc kiln slag has higher economical efficiency, but the grinding part is required to be refined, and the operation procedure and the cost are increased;
(2) The reduction and vulcanization method is that a certain amount of reducing agent is added during reduction smelting, the melting temperature of the obtained product can be reduced (from the original 1600 ℃ to 1250-1300 ℃), and the alloy powder is electrolyzed and separated into pure Fe, ag and Ga anode slime. The collection of pure Fe obtained therein is of great benefit, but the problem to be considered is the emission of flue gas SO 2 The effect of contamination problems;
(3) Blast furnace smelting process: in the production process, zinc kiln slag is mixed with a certain amount of coke and vulcanizing agent, and then the mixture is put into a blast furnace for smelting, so that three products of zinc oxide smoke dust, slag and matte are finally obtained. The process only enriches and recovers copper and zinc in the zinc kiln slag, but the iron content in the zinc kiln slag is higher and has high utilization value, and the copper and the zinc in the zinc kiln slag are not recovered and utilized;
(4) Melt chlorination volatilization method: the process has the advantages of self-heating and high enrichment rate of valuable elements in ash, liu Zhi macro and the like, and adopts a melt chlorination volatilization method to treat the kiln slag, and researches show that the volatilization rate of lead, copper and germanium reaches higher volatilization rates of 96.79%, 97.36%, 82.71% and 91.78% respectively by controlling the melt chlorination volatilization time and the chlorinating agent, but the volatilization rates of zinc and copper are low, and the volatilization index of gallium is not ideal. Moreover, this method has a major problem that the chloridizing volatilization has a great influence on the corrosiveness of the equipment in the industrial production process;
(5) The bath smelting process, which was developed in australia and the like, has many advantages, such as: energy saving, simple operation and comprehensive recovery of valuable metals. Zhou Hongwu and the like treat zinc leaching residues of plant smelting plants by adopting a molten pool smelting method, and research results show that the recovery rate of the added capturing agent on silver is more than 90 percent, the recovery rate of other valuable metals copper and zinc is more than 80 percent, and the recovery rate of lead is better recovered to 90 percent, but the number of times of reversion in the process is increasedIn the presence of SO 2 Pollution problems.
Disclosure of Invention
The invention aims to provide a method for extracting metal iron from zinc kiln slag, which solves the problem of waste of a large amount of metal resources caused by low utilization rate of the zinc kiln slag in the traditional process, fully utilizes valuable metal iron in the zinc kiln slag and improves the added value of the zinc kiln slag.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a method for extracting metallic iron from zinc kiln slag, which comprises the following steps in sequence:
s1, fixing a zinc kiln slag material on an electrode rod to serve as a cathode; fixing a graphite rod on an electrode rod to serve as a positive electrode;
s2, mixing sodium chloride and potassium chloride, and heating to melt to obtain a molten salt system;
s3, in the atmosphere of protective gas, respectively inserting a cathode electrode and an anode electrode into a molten salt system to form a reaction system, and carrying out molten salt constant-tank pressure electrolysis reaction;
s4, after the electrolytic reaction is finished, cooling the reaction system, taking out the cathode electrode, and sequentially cleaning and drying to obtain the metal iron.
In the step S1, the hardness of the zinc kiln slag material is 5.5-10HB.
As another limitation, the zinc kiln slag material is residues generated after zinc tailings generated after zinc ore zinc smelting are subjected to high-temperature reduction and zinc and lead recovery.
As a third limitation, in step S2, the molar ratio of sodium chloride to potassium chloride is 1:0.4-2.5;
the temperature after heating is 160-240 ℃ and the heat preservation time is 2-6h;
the temperature rising rate is 3-8 ℃/min, the temperature after temperature rising is 360-440 ℃, and the heat preservation time is 12-24h.
As a fourth limitation, in step S3, the protective gas is argon or nitrogen;
the mass ratio of the cathode electrode to the molten salt system to the anode electrode is 1:100-150:6-12;
the electrolysis reaction temperature is 750-950 ℃, the time is 8-12h, and the voltage is 2-3v.
As a fifth limitation, in step S4, the temperature after cooling is 15-35 ℃;
the cleaning is to sequentially wash in distilled water and ultrasonic waves;
the drying is carried out at 100-150 ℃ for 30-70min.
By adopting the technical scheme, compared with the prior art, the invention has the following technical progress:
(1) the method for extracting the metallic iron from the zinc kiln slag provided by the invention adopts a molten salt electro-deoxidation mode to recover the metallic iron, solves the problems of low extraction rate and high extraction difficulty caused by the complex zinc kiln slag system in the traditional process, and simultaneously avoids the problems of severe environmental pollution, higher reaction temperature and the like caused by the addition of a plurality of reagents such as a reducing agent or a vulcanizing agent in the traditional process;
(2) the method for extracting the metallic iron from the zinc kiln slag has the advantages of simple operation, concise flow, high recovery rate of the metallic iron, 750-950 ℃ of temperature in the reaction process, lower temperature of a reaction system compared with 1250-1300 ℃ in the traditional process, reduced energy consumption and accordance with the concept of green environmental protection;
(3) according to the method for extracting metallic iron from zinc kiln slag, sodium chloride and potassium chloride are used as molten salt systems, and compared with aluminum chloride and calcium chloride which are molten salt systems in traditional electro-deoxidation, the method has the advantages that the cost is reduced, and meanwhile, the reaction rate is improved.
The method is suitable for extracting the metallic iron from the zinc kiln slag.
Drawings
The invention will be described in more detail below with reference to the attached drawings and specific examples:
FIG. 1 is a molten salt phase diagram of a KCl-NaCl molten salt system in example 1 of the present invention;
FIG. 2 is a schematic diagram of the electrolytic reaction used in examples 1 to 6 of the present invention;
FIG. 3 is an XRD spectrum of the product of example 1 of the present invention after electrolysis.
Detailed Description
The invention will now be described in further detail by way of specific examples, which are to be understood as illustrative only and not limiting.
Example 1A method for determining the amount of Components in a molten salt System
The following six groups of molten salt systems alpha are respectively prepared 1 -α 6 And melting is carried out respectively, and molten salt phase diagrams of six groups of solids are measured, as shown in fig. 1:
α 1 1mol (58.5 g) anhydrous sodium chloride;
α 2 0.2mol (11.7 g) of anhydrous sodium chloride and 0.8mol (59.6 g) of anhydrous potassium chloride;
α 3 0.4mol (23.4 g) of anhydrous sodium chloride and 0.6mol (44.7 g) of anhydrous potassium chloride;
α 4 0.6mol (35.1 g) of anhydrous sodium chloride and 0.4mol (29.8 g) of anhydrous potassium chloride;
α 5 0.8mol (46.8 g) of anhydrous sodium chloride and 0.2mol (14.9 g) of anhydrous potassium chloride;
α 6 1mol (74.5 g) of anhydrous potassium chloride;
as can be seen from fig. 1, the molar ratio of sodium chloride to potassium chloride is 1:0.4-2.5, the state of the molten salt system reaches an optimal value, and the temperature of the molten salt system is kept at a low level, namely 657-700 ℃.
Example 2 method of extracting metallic iron from Zinc kiln slag
The reaction principle of this example is shown in FIG. 2.
The embodiment comprises the following steps sequentially carried out:
a. adding a certain amount of coke into leaching slag (namely zinc tailings) generated after zinc ore zinc hydrometallurgy, reducing at high temperature in a rotary kiln, recovering metals such as zinc and lead, and the like, and generating residues), grinding in a ball mill to obtain powder with uniform granularity, compacting 10kg of powder into blocks under the condition of 8MP pressure, and sintering in a muffle furnace at 700 ℃ for 6 hours to enhance the hardness of the zinc kiln slag material, thereby preparing the zinc kiln slag material for later use; the hardness of the zinc kiln slag material is 7.8HB through detection;
b. taking 10000mol (585 kg) of anhydrous sodium chloride and 10000mol (745 kg) of anhydrous potassium chloride, respectively grinding and uniformly mixing, firstly heating to 160 ℃ and preserving heat for 4 hours, removing physical adsorption water, then continuously heating to 360 ℃ at a speed of 5 ℃/min and preserving heat for 18 hours, and removing chemical bonding water to prepare a molten salt system;
c. fixing zinc kiln slag material on an electrode rod to serve as a cathode; fixing 80kg of graphite rod on an electrode rod as an anode, immersing a cathode electrode and the anode electrode in a molten salt system in an argon atmosphere, switching on a direct-current voltage-stabilizing power supply, regulating the electrolysis voltage to be 2.3V, and carrying out electrolysis reaction at the temperature of the molten salt system of 800 ℃ for 10 hours;
d. cooling the reaction system after the electrolytic reaction to 25 ℃, taking out the cathode electrode, fully cleaning with distilled water, then cleaning with ultrasonic waves to remove residual molten salt in the cathode plate, then placing in a drying box at 120 ℃ for drying for 50min to obtain 5.78kg of reaction product, and performing XRD detection on the reaction product, wherein the detection result is shown in figure 3.
As can be seen from fig. 2: the main phase of the product after electrolysis is metallic Fe phase, and less FeO phase and Ca are contained in the product 2 (Al 2 O 3 ) And Ti is 4 O 7 Less experimental results show that the metal Fe simple substance can be extracted from the zinc kiln slag by a molten salt electro-deoxidation method, and the XRD analysis shows that the content of Fe in the electrolysis product is 86.75 percent.
EXAMPLES 3-7 method for extracting metallic iron from Zinc kiln slag
Examples 3-7 are a method for extracting metallic iron from zinc kiln slag, respectively, which are all implemented according to the reaction principle shown in fig. 2, and their steps are basically the same as those of example 1, except that the process parameters are different, and specific details are shown in table 1:
Claims (3)
1. a method for extracting metallic iron from zinc kiln slag, which is characterized by comprising the following steps in sequence:
s1, fixing a zinc kiln slag material on an electrode rod to serve as a cathode electrode, and fixing a graphite rod on the electrode rod to serve as an anode electrode;
the zinc kiln slag material is residues generated after zinc tailings generated after zinc ore zinc smelting are subjected to high-temperature reduction and zinc and lead recovery;
s2, mixing sodium chloride and potassium chloride, wherein the molar ratio of the sodium chloride to the potassium chloride is 1:0.4-2.5, heating to 160-240 ℃ and preserving heat for 2-6h; then heating to 360-440 ℃ at a heating rate of 3-8 ℃/min for 12-24 hours to obtain a molten salt system;
s3, in the atmosphere of protective gas, respectively inserting a cathode electrode and an anode electrode into a molten salt system to form a reaction system, and carrying out molten salt constant-tank pressure electrolysis reaction;
the protective gas is argon or nitrogen;
the mass ratio of the cathode electrode to the molten salt system to the anode electrode is 1:100-150:6-12;
the electrolysis reaction temperature is 750-950 ℃, the time is 8-12h, and the voltage is 2-3v;
s4, after the electrolytic reaction is finished, cooling the reaction system, taking out the cathode electrode, and sequentially cleaning and drying to obtain the metal iron.
2. A method for extracting metallic iron from zinc kiln slag as defined in claim 1, wherein, in step S1,
the hardness of the zinc kiln slag material is 5.5-10HB.
3. A process for extracting metallic iron from zinc kiln slag according to claim 1 or 2, characterized in that,
in the step S4, the temperature after cooling is 15-35 ℃;
the cleaning is to sequentially wash in distilled water and ultrasonic waves;
the drying is carried out at 100-150 ℃ for 30-70min.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5194124A (en) * | 1991-11-26 | 1993-03-16 | E. I. Du Pont De Nemours And Company | Molten salt electrolytic beneficiation of iron oxide-containing titaniferous ores to produce iron and high-grade TiO2 |
| CN101906646A (en) * | 2010-07-21 | 2010-12-08 | 东北大学 | Method for preparing iron metal by molten salt electrolysis of iron ore |
| CN105838892A (en) * | 2016-04-06 | 2016-08-10 | 北京科技大学 | Method for extracting titanium, iron, manganese, vanadium and chromium from vanadium slag of iron and steel plant |
| JP2017128808A (en) * | 2016-01-18 | 2017-07-27 | 讓 佐藤 | Method for recovering zinc from zinc-containing waste substance |
| CN110760890A (en) * | 2019-11-27 | 2020-02-07 | 东北大学 | Method for treating smelting slag by electrolytic reduction of aluminum molten salt |
| CN111705336A (en) * | 2020-06-11 | 2020-09-25 | 华北理工大学 | Method for recovering nickel simple substance from waste lithium battery |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB0504444D0 (en) * | 2005-03-03 | 2005-04-06 | Univ Cambridge Tech | Method and apparatus for removing oxygen from a solid compound or metal |
-
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- 2021-08-11 CN CN202110919176.7A patent/CN113802149B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5194124A (en) * | 1991-11-26 | 1993-03-16 | E. I. Du Pont De Nemours And Company | Molten salt electrolytic beneficiation of iron oxide-containing titaniferous ores to produce iron and high-grade TiO2 |
| CN101906646A (en) * | 2010-07-21 | 2010-12-08 | 东北大学 | Method for preparing iron metal by molten salt electrolysis of iron ore |
| JP2017128808A (en) * | 2016-01-18 | 2017-07-27 | 讓 佐藤 | Method for recovering zinc from zinc-containing waste substance |
| CN105838892A (en) * | 2016-04-06 | 2016-08-10 | 北京科技大学 | Method for extracting titanium, iron, manganese, vanadium and chromium from vanadium slag of iron and steel plant |
| CN110760890A (en) * | 2019-11-27 | 2020-02-07 | 东北大学 | Method for treating smelting slag by electrolytic reduction of aluminum molten salt |
| CN111705336A (en) * | 2020-06-11 | 2020-09-25 | 华北理工大学 | Method for recovering nickel simple substance from waste lithium battery |
Non-Patent Citations (4)
| Title |
|---|
| An overview of recovery of metals from slags;Huiting Shen等;《Waste Management》;第23卷;933–949 * |
| Iron and copper recovery from copper slags through smelting with waste cathode carbon from aluminium electrolysis;MAO Kai-xuan等;《J. Cent. South Univ.》;第28卷;2010−2021 * |
| ＬｉＣｌ－ＫＣｌ熔盐中电解还原钛铁矿的研究;崔鹏等;《有色金属（冶炼部分）》(第11期);11-18,27 * |
| 氧化锌矿处理方法现状;申亚芳;张馨圆;王乐;张硕;邓孝纯;;矿产综合利用(第02期);23-28,36 * |
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