CN114410982B - Deep bismuth removal method for lead fire refining - Google Patents
Deep bismuth removal method for lead fire refining Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B13/00—Obtaining lead
- C22B13/06—Refining
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B13/00—Obtaining lead
- C22B13/02—Obtaining lead by dry processes
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/10—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/06—Making non-ferrous alloys with the use of special agents for refining or deoxidising
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C11/00—Alloys based on lead
- C22C11/02—Alloys based on lead with an alkali or an alkaline earth metal as the next major constituent
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
The invention discloses a deep bismuth removal method for lead fire refining, which is characterized by comprising the following steps of: the deep bismuth removal method comprises the following steps: melting lead or directly taking lead liquid, and controlling the temperature of the lead liquid to be 450-550 ℃; adding calcium into the lead liquid and completely melting the calcium, and cooling the lead liquid to 345-390 ℃ while stirring; after maintaining the temperature and stirring for 2-5 minutes, adding a slag reducing agent into the lead liquid, and continuing stirring for 2-15 minutes to reduce the temperature of the lead liquid to 320-345 ℃; and (5) maintaining the temperature for 10-30 minutes, and fishing out the scum to finish the deep bismuth removal process. The invention can reduce the bismuth content of lead to below 0.005% in the deep bismuth removing process, and the slag yield is halved compared with a calcium-magnesium bismuth removing method. The invention has the most remarkable effect of preparing lead-calcium alloy by refining and regenerating the reduced lead, and can obtain the product by directly adjusting the contents of tin, calcium and aluminum without further refining after removing bismuth and stibium and copper.
Description
Technical Field
The invention belongs to the technical field of lead smelting, and particularly relates to a deep bismuth removal method for lead fire refining, which is used for deep bismuth removal in the lead fire refining process and solves the problem that the quality requirement of a user cannot be met due to exceeding of bismuth content of refined lead or lead alloy.
Background
Lead bullion refining is mainly divided into fire refining and electrolytic refining, and foreign lead bullion refining mainly adopts fire, and domestic lead bullion electrolytic refining mainly. Electrolytic refining utilizes different dissolution and precipitation potentials of different metals to realize separation of lead and other metals, thus achieving the purpose of purifying crude lead; bismuth is the most difficult impurity to remove in the fire refining of crude lead, and a calcium-magnesium bismuth removal method is generally adopted abroad, and bismuth slag is formed by separating bismuth from calcium-magnesium to generate a high-melting-point metal compound from lead. The bismuth content can be reduced to 0.008% by adopting the method, but the bismuth content is difficult to be less than 0.005, the slag yield of the bismuth removing method of calcium and magnesium is large, generally 10-20%, and the consumption cost of calcium and magnesium is high. The regenerated lead industry reduces and smelts various lead-containing wastes to produce reduced lead, the refining process generally does not have bismuth removal working procedures, so that the lead is continuously accumulated in the recycling process, the content of bismuth in refined lead or lead alloy exceeds the standard, the utilization is limited, and the bismuth removal working procedures are needed to be added for solving the problem.
Patent CN112410577 a discloses a method for refining refined lead by removing bismuth by using a fire method, adding calcium-aluminum alloy, magnesium powder and lead-antimony alloy, removing bismuth deeply by adding antimony by using a calcium-magnesium bismuth removing method, the method has the advantages of large material consumption and high slag yield, and the added calcium, aluminum, magnesium and antimony are required to be refined and removed in the later refining process, so that the medicament consumption and ash production are high, the production cost is high, and the enterprise is difficult to popularize.
The deep bismuth removal of the lead bullion needs to be established on the basis of low material consumption and low slag return quantity, and the retention of beneficial components and the removal of harmful components in the lead bullion are considered, so that the material utilization rate is improved, the product quality problem is solved, and meanwhile, the production cost is effectively reduced.
Disclosure of Invention
The purpose of the invention is that: the deep bismuth removal method for the lead fire refining is provided, the deep bismuth removal procedure is embedded in the lead fire refining process, the impurity removal sequence is reasonably arranged, the material consumption can be reduced, and the synergistic impurity removal effect is generated.
The invention is realized by the following technical scheme: a method for deeply removing bismuth by lead fire refining is characterized in that: the deep bismuth removal method comprises the following steps: melting lead or directly taking lead liquid, and controlling the temperature of the lead liquid to be 450-550 ℃; adding calcium into the lead liquid and completely melting the calcium, and cooling the lead liquid to 345-390 ℃ while stirring; after maintaining the temperature and stirring for 2-5 minutes, adding a slag reducing agent into the lead liquid, and continuing stirring for 2-15 minutes to reduce the temperature of the lead liquid to 320-345 ℃; and (5) maintaining the temperature for 10-30 minutes, and fishing out the scum to finish the deep bismuth removal process.
Further: the slag reducing agent comprises the following components in percentage by mass: 10-25% of carbon powder, 50-70% of sodium hydroxide, 1-10% of sodium carbonate, 1-10% of sodium sulfate, 1-10% of borax, 1-5% of sodium chloride and 1-5% of magnesium chloride.
Further: the lead or lead liquid is prepared by refining crude lead by a fire method to remove copper, arsenic, antimony and tin, silver, zinc and bismuth, and the bismuth content is less than 0.02%; or lead liquid prepared by reducing lead and removing tin and copper.
Further: the optimal temperature of calcium adding is 480-500 ℃, the optimal temperature of slag adding and adding agent is 350-360 ℃, and the optimal temperature of slag dragging is 325-340 ℃.
Further: the lead liquid can be cooled by adding cold materials after calcium addition, and stirring and natural cooling can be synchronously performed.
Further: the stirring time after calcium addition is 1-20 minutes, and the calcium content in the lead liquid after calcium addition is 0.8-2 per mill; the addition amount of the slag reducing agent is 1-5 per mill of the total mass of lead.
Further: the added calcium in the lead liquid is simple substance calcium or high calcium lead;
further: the high-calcium lead is lead-calcium alloy with calcium content not less than 5 per mill.
The invention has the advantages that: according to the scheme, the deep bismuth removal process is added in the lead fire refining process, so that the bismuth content of lead can be reduced to below 0.005%, part of the bismuth can approach or reach the standard of No. 1 refined lead, meanwhile, the slag yield is halved compared with a calcium-magnesium bismuth removal process, and a small amount of impurity antimony and copper in the lead are removed cooperatively. The invention has the most remarkable effect of preparing lead-calcium alloy by refining and regenerating the reduced lead, and can obtain the product by directly adjusting the contents of tin, calcium and aluminum without further refining after removing bismuth and stibium and copper.
Detailed Description
The invention provides a deep bismuth removal method for lead fire refining, which comprises the following steps: melting lead or directly taking lead liquid, and controlling the temperature of the lead liquid to be 450-550 ℃; adding calcium into the lead liquid and completely melting the calcium, and cooling the lead liquid to 345-390 ℃ while stirring; after maintaining the temperature and stirring for 2-5 minutes, adding a slag reducing agent into the lead liquid, and continuing stirring for 2-15 minutes to reduce the temperature of the lead liquid to 320-345 ℃; and (5) maintaining the temperature for 10-30 minutes, and fishing out the scum to finish the deep bismuth removal process.
The present invention will be described in detail with reference to specific examples.
Firstly, preparing a slag reducing agent:
weighing powdered activated carbon 4kg, caustic soda flakes 13 kg, sodium carbonate 1 kg, sodium sulfate 0.6 kg, borax 1 kg, sodium chloride 0.2 kg and magnesium chloride 0.2 kg, putting into a mixer, stirring for 10 minutes, bagging and sealing to obtain the No. 1 slag reducing agent for later use.
Weighing carbon powder 2kg, sodium hydroxide 12kg, sodium carbonate 2kg, sodium sulfate 1 kg, borax 1 kg, sodium chloride 1 kg and magnesium chloride 1 kg, putting into a mixer, stirring for 10 minutes, bagging and sealing to obtain the No. 2 slag reducing agent for later use.
Although the proportions of the two slag reducing agents are listed, the proportions within the range described in the scheme can have similar effects through experiments.
Example 1
Weighing 12kg of reduced lead, 12g of calcium and 20g of No. 1 slag reducing agent for standby; heating the pit furnace at 480 ℃, putting 20kg of iron crucible into the pit furnace, successively putting reduced lead into the crucible for melting, fishing out dross on the surface of the lead liquid after the lead liquid reaches the set temperature, and sampling and testing the lead liquid; adding all calcium into a crucible and pressing the calcium into the lead liquid, adjusting the set temperature to 350 ℃ after the calcium is completely melted, stirring for 10 minutes, and cooling; stirring for 5 minutes after the lead liquid reaches the set temperature, adding a slag reducing agent and stirring for 10 minutes; and (3) adjusting the set temperature to 330 ℃, cooling, keeping the temperature and standing for 20 minutes after the temperature is reached, fishing out the dross on the surface of the lead liquid, checking weighing of 0.65kg, and sampling and testing the lead liquid. Reduced lead analysis results: sb 0.0289%, bi 0.00771%, cu 0.00699%, analysis results after bismuth removal: 0.00043% of Sb, 0.0038% of Bi and 0.00044% of Cu, and the calculated slag rate is 5.42%.
Example 2
Weighing 12kg of No. 2 refined lead, 16g of calcium and 25g of No. 2 slag reducing agent for standby; heating the pit furnace at 500 ℃, putting 20kg of iron crucible into the pit furnace, sequentially putting 2# refined lead into the crucible for melting, fishing out dross on the surface of the lead liquid after the lead liquid reaches the set temperature, and sampling and testing the lead liquid; adding calcium into the crucible and pressing into the lead liquid, adjusting the set temperature to 360 ℃ after the calcium is melted completely, stirring for 15 minutes, and cooling; stirring for 4 minutes after the lead liquid reaches the set temperature, adding a slag reducing agent and stirring for 12 minutes; and (3) regulating the set temperature to 335 ℃, cooling, keeping the temperature and standing for 25 minutes after the temperature is reached, fishing out the dross on the surface of the lead liquid, checking weighing 0.7kg, and sampling and testing the lead liquid. Results of analysis of refined lead No. 2: sb 0.00048%, bi 0.00712%, cu 0.00062%, analysis after bismuth removal: 0.00027% of Sb, 0.00405% of Bi and 0.00056% of Cu, and the calculated slag rate was 5.83%.
Example 3
Weighing 12kg of mixed lead, 24g of calcium and 30g of No. 1 slag reducing agent for standby; heating the pit furnace at 490 ℃, putting 20kg of iron crucible into the pit furnace, successively putting mixed lead into the crucible for melting, fishing out dross on the surface of the lead liquid after the lead liquid reaches the set temperature, and sampling and testing the lead liquid; adding all calcium into a crucible and pressing the calcium into the lead liquid, adjusting the set temperature to 350 ℃ after the calcium is completely melted, stirring for 15 minutes, and cooling; stirring for 3 minutes after the lead liquid reaches the set temperature, adding a slag reducing agent and stirring for 10 minutes; and (3) regulating the set temperature to 325 ℃, cooling, keeping the temperature and standing for 20 minutes after the temperature is reached, fishing out the dross on the surface of the lead liquid, checking the weight of the lead liquid to 0.83kg, and sampling and testing the lead liquid. Results of lead analysis: sb 0.03488%, bi 0.00704%, cu 0.02771%, analysis after bismuth removal: 0.00062% of Sb, 0.00397% of Bi and 0.00281% of Cu, and the calculated slag rate is 6.92%.
Example 4
Weighing 6005kg of No. 2 refined lead, 7.2kg of calcium and 12kg of No. 1 slag reducing agent for later use; putting the No. 2 refined lead into a 6t lead pot for production to perform normal tin removal, antimony and copper operation, and then sampling and testing; heating the lead liquid to 500 ℃, sequentially pressing calcium into the lead liquid, stirring for 20 minutes after the calcium is completely melted, and cooling to 350 ℃; stirring for 5 minutes, adding a slag reducing agent and stirring for 15 minutes; cooling to 330 ℃, keeping the temperature and standing for 20 minutes, fishing out the scum on the surface of the lead liquid, checking 324kg of the scum, and sampling and testing the lead liquid. Analysis results before calcium addition: sb 0.00042%, bi 0.00621%, cu 0.00076%, analysis results after bismuth removal: 0.00026% of Sb, 0.00392% of Bi and 0.00058% of Cu, and the calculated bismuth slag removal rate is 5.4%.
By comparing analysis results before and after the deep bismuth removal in the embodiment, the content of bismuth in the lead can be reduced to below 0.005% by matching the calcium in the lead with the slag reducing agent, the index requirement of No. 1 refined lead is approached or reached, meanwhile, the bismuth removing slag rate can be controlled within 7% by having a certain effect on removing antimony and copper in the lead; the common method for removing bismuth by adding calcium and magnesium generally removes bismuth to about 0.008 percent, and the bismuth slag removal rate is about 15 percent, if the bismuth removal depth is further increased, the addition amount of calcium and magnesium is required to be increased, the slag yield is also increased, and the production cost is unacceptable. Compared with a calcium-magnesium bismuth removal method, the method has the advantages of bismuth removal depth and slag yield, and is suitable for production, application and popularization.
Claims (7)
1. A method for deeply removing bismuth by lead fire refining is characterized in that: the deep bismuth removal method comprises the following steps: melting lead or directly taking lead liquid, and controlling the temperature of the lead liquid to be 450-550 ℃; adding calcium into the lead liquid and completely melting the calcium, and cooling the lead liquid to 345-390 ℃ while stirring; after maintaining the temperature and stirring for 2-5 minutes, adding a slag reducing agent into the lead liquid, and continuing stirring for 2-15 minutes to reduce the temperature of the lead liquid to 320-345 ℃; keeping the temperature for 10-30 minutes, and fishing out scum to finish the deep bismuth removal process;
the slag reducing agent comprises the following components in percentage by mass: 10-25% of carbon powder, 50-70% of sodium hydroxide, 1-10% of sodium carbonate, 1-10% of sodium sulfate, 1-10% of borax, 1-5% of sodium chloride and 1-5% of magnesium chloride.
2. The deep bismuth removal method for lead fire refining according to claim 1, wherein the method comprises the following steps: the lead or lead liquid is prepared by refining crude lead by a fire method to remove copper, arsenic, antimony and tin, silver, zinc and bismuth, and the bismuth content is less than 0.02%; or lead liquid prepared by reducing lead and removing tin and copper.
3. The deep bismuth removal method for lead fire refining according to claim 1, wherein the method comprises the following steps: the optimal temperature of calcium adding is 480-500 ℃, the optimal temperature of slag adding and adding agent is 350-360 ℃, and the optimal temperature of slag dragging is 325-340 ℃.
4. The deep bismuth removal method for lead fire refining according to claim 1, wherein the method comprises the following steps: and cooling the lead liquid after calcium addition, adding a cold material for cooling, and stirring and naturally cooling synchronously.
5. The deep bismuth removal method for lead fire refining according to claim 1, wherein the method comprises the following steps: the stirring time after calcium addition is 1-20 minutes, and the calcium content in the lead liquid after calcium addition is 0.8-2 per mill; the addition amount of the slag reducing agent is 1-5 per mill of the total mass of lead.
6. The deep bismuth removal method for lead fire refining according to claim 1, wherein the method comprises the following steps: the added calcium in the lead liquid is simple substance calcium or high calcium lead.
7. The deep bismuth removal method by lead fire refining as claimed in claim 6, wherein: the high-calcium lead is lead-calcium alloy with calcium content not less than 5 per mill.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2451588A (en) * | 1988-05-20 | 1989-11-23 | Timminco Limited | Magnesium-calcium alloys for debismuthizing lead |
| CN106282659A (en) * | 2016-08-21 | 2017-01-04 | 株洲冶炼集团股份有限公司 | A kind of lead smelting removes antimony agent and except antimony technique with compound |
| CN107663592A (en) * | 2016-07-27 | 2018-02-06 | 江西金洋金属有限公司 | A kind of method that lead liquid is purified using deslagging agent |
| CN111876610A (en) * | 2020-08-05 | 2020-11-03 | 浙江巨江电源制造有限公司 | Lead slag reducing agent and preparation method thereof |
| CN112410577A (en) * | 2020-10-12 | 2021-02-26 | 浙江天能电源材料有限公司 | Method for removing bismuth and refining refined lead by pyrogenic process |
-
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- 2021-12-23 CN CN202111586018.0A patent/CN114410982B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2451588A (en) * | 1988-05-20 | 1989-11-23 | Timminco Limited | Magnesium-calcium alloys for debismuthizing lead |
| CN107663592A (en) * | 2016-07-27 | 2018-02-06 | 江西金洋金属有限公司 | A kind of method that lead liquid is purified using deslagging agent |
| CN106282659A (en) * | 2016-08-21 | 2017-01-04 | 株洲冶炼集团股份有限公司 | A kind of lead smelting removes antimony agent and except antimony technique with compound |
| CN111876610A (en) * | 2020-08-05 | 2020-11-03 | 浙江巨江电源制造有限公司 | Lead slag reducing agent and preparation method thereof |
| CN112410577A (en) * | 2020-10-12 | 2021-02-26 | 浙江天能电源材料有限公司 | Method for removing bismuth and refining refined lead by pyrogenic process |
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