A method for recovering tin from low-grade tin-containing materials in lead smelting

Abstract

The present application belongs to the technical field of metal smelting, and discloses a method for recovering tin from low-grade tin-containing material in lead smelting, comprising the following steps: mixing lead ore powder, returned dust and high-tin lead slag to form a mixture, adding coal powder into the mixture, and smelting in a bottom-blown furnace to produce primary lead, smelting slag, flue gas and dust; flowing the smelting slag in a liquid state into a reduction furnace for smelting to produce high-tin lead, slag and dust; melting the high-tin lead to produce high-tin high-copper lead dross and high-tin lead liquid, and producing crude tin and lead liquid through vacuum smelting of the high-tin lead liquid; producing high-tin secondary zinc oxide through fuming of the slag; reducing and smelting the high-tin high-copper lead dross to produce high-tin lead and copper matte; returning the high-tin lead to the recovery of tin; acid leaching the high-tin secondary zinc oxide to produce an acid leaching solution and high-tin lead slag, and recycling the high-tin lead slag. The present application enriches tin in the secondary lead precipitation, produces high-tin lead, and achieves the purpose of efficient recovery of tin.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal smelting, and relates to a method for recovering tin from low-grade tin-containing material in lead smelting. BACKGROUND

[0002] With the exploitation and utilization of lead mineral resources, the rich ore resources are greatly reduced. Along with the increase in the procurement difficulty of various lead primary ore powders and the reduction of processing costs, the recovery of low-grade tin-rich material has become a main breakthrough point for lead smelting enterprises to improve profits.

[0003] Tin is widely used in various fields such as industry and electronics, and tin smelting has also developed rapidly. However, in the use process of low-grade tin-containing lead material, the tin cannot be effectively enriched in the lead smelting process, and the recovery purpose cannot be achieved. SUMMARY

[0004] The application provides a method for recovering tin from low-grade tin-containing material in lead smelting, which solves the technical problem that tin cannot be effectively recovered in the lead smelting process. The method realizes twice lead precipitation through bottom blowing smelting and reduction smelting, reduces the yield of secondary lead precipitation, so that the tin is enriched in the secondary lead precipitation, high-tin lead is produced, and after the high-tin lead is purified, crude tin is produced by vacuum smelting. The slag and ash produced in the whole recovery process are recycled, and the purpose of efficient recovery of tin is achieved.

[0005] To achieve the above purpose, the application adopts the following technical scheme:

[0006] The application provides a method for recovering tin from low-grade tin-containing material in lead smelting, which includes the following steps:

[0007] 1) The lead ore powder, returned dust and high-tin lead slag are mixed into a mixture, and then coal powder is added, and the mixture is smelted in a bottom blowing furnace at 1000-1250 DEG C to produce primary lead, smelting slag, flue gas and dust. The primary lead is sent to the next process for treatment, the flue gas is sent to the acid production, and the dust is returned to the batching;

[0008] 2) The smelting slag in step 1) is flowed into a reduction furnace in a liquid state and smelted at 1000-1200 DEG C to produce high-tin lead, slag and dust, and the dust is returned to step 1) for batching;

[0009] 3) The high-tin lead in step 2) is melted and slagged to produce high-tin high-copper lead dross and high-tin lead liquid, the high-tin lead liquid is vacuum smelted to produce crude tin and lead liquid, and the lead liquid is sent to the electrolysis process;

[0010] 4) The slag in step 2) is smoked to produce high-tin secondary zinc oxide;

[0011] 5) The high-tin high-copper lead dross in step 3) is subjected to reduction smelting to produce high-tin lead and copper matte; the high-tin lead is returned to step 3) to repeat the tin recovery, and the copper matte is sent to a copper recovery process;

[0012] 6) The high-tin secondary zinc oxide in step 4) is subjected to acid leaching to obtain an acid leaching solution and high-tin lead residue; the acid leaching solution is sent to a zinc recovery process, and the high-tin lead residue is returned to step 1) for recycling.

[0013] Preferably, in step 1), the mass percentage of the lead ore powder, the returned flue dust and the high-tin lead residue in the mixture is as follows: 70-85%, 10-20% and 5-10%, respectively; the Pb content in the mixture is 20-50%, and the S content is 10-20%; and the amount of the added coal powder is 1-10% of the mixture.

[0014] Preferably, in step 3), the temperature during the melting and slagging is 400-450°C.

[0015] Preferably, in step 4), the temperature during the fuming is 1000-1150°C.

[0016] Preferably, in step 5), the temperature during the reduction smelting is 1000-1200°C.

[0017] Preferably, in step 6), the pH value during the acid leaching is 3.5-4.5.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] 1. In the present application, the tin in the low-grade tin-containing material is enriched in lead through the three steps of oxidation desulfurization, reduction and fuming in lead smelting by adjusting the ratio of the lead ore powder and the sulfur in the raw material and the smelting conditions of oxygen, coal and natural gas, so that the tin is recovered, the tin recovery rate is high, and the tin content in the discarded residue is less than 0.1%.

[0020] 2. In the present application, the recycling of various slag and ash materials is scientifically set according to the flow direction of the tin element in lead smelting, which takes into account the recovery of the original lead, copper and zinc while improving the tin recovery rate, and the tin recovery rate is more than 90%, and the recovery rates of lead, copper and zinc are also greatly improved.

[0021] 3. The present application expands the application range of lead smelting materials and improves the adaptability of lead smelting materials.

[0022] 4. In the present application, through bottom blowing smelting and reduction smelting, lead is precipitated twice, the yield of secondary lead precipitation is reduced, so that the tin is enriched in the secondary lead precipitation, high-tin lead is produced, and after the high-tin lead is purified, crude tin is directly produced in vacuum, the slag and ash produced in the whole recovery process are recycled, and the purpose of efficient recovery of tin is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1A process flow chart of a method for recovering tin from low-grade tin-containing material in lead smelting according to the present application. DETAILED DESCRIPTION

[0024] The following examples are used to illustrate the present application, but are not intended to limit the scope of protection of the present application. If not specifically indicated, the technical means used in the examples are conventional means known to those skilled in the art. The test methods used in the following examples are conventional methods, unless otherwise specified.

[0025] The percentage composition of the lead ore powder used in the following examples is as follows: Pb 20-50%, S 10-20%, Sn >0.1%.

[0026] Example 1

[0027] A method for recovering tin from low-grade tin-containing material in lead smelting, comprising the following steps:

[0028] 1) The lead ore powder, returned dust and high-tin lead slag are mixed in a ratio of 70%:20%:10% to form a mixture, and the mixture composition is: Pb 48%, S 15%; 8% of coal powder is then added, and the mixture is smelted in a bottom-blown furnace at 1200°C, with an oxygen material ratio of 110 m 3 / t, natural gas 55 m 3 / t, Fe / SiO2 being 3:1, to produce primary lead, smelting slag, flue gas and dust; the primary lead contains Pb 93-98% and almost no tin, with a yield of 90%, and the primary lead is sent to the next process; the flue gas is sent to an acid production process, and the dust is returned to the batching process; the smelting slag contains Pb 15%.

[0029] 2) The smelting slag in step 1) is smelted in a reduction furnace at 1150°C in a liquid state, with a coal amount of 10%, natural gas 8 m 3 / t, to produce high-tin lead (secondary lead), slag and dust, and the dust is returned to the batching process in step 1); the high-tin lead contains Pb 88-93% and Sn >4%; the yield is 10%.

[0030] 3) The high-tin lead in step 2) is smelted and slagged, with a temperature of 420°C, to produce high-tin high-copper lead dross and high-tin lead liquid, and the high-tin lead liquid is vacuum smelted to produce crude tin and lead liquid, and the lead liquid is sent to an electrolysis process; the high-tin high-copper lead dross contains Sn 4.5%, Cu 28% and Pb 50%; the crude tin contains Sn 90%.

[0031] 4) The slag in step 2) is fumed, with a fuming temperature of 1150°C, a coal amount of 25% and a wind pressure of 0.06 MPa, to produce high-tin zinc suboxide, and the high-tin zinc suboxide contains Sn 0.8% and Zn 70%.

[0032] 5) The high-tin high-copper lead dross in step 3) is subjected to reduction smelting, the smelting temperature is 1200°C, and high-tin lead and copper matte are produced; the high-tin lead contains Sn 2%, and is returned to step 3) to recycle tin; the copper matte contains Cu 45%, and is sent to a copper recovery process.

[0033] 6) The high-tin zinc suboxide in step 4) is subjected to acid leaching, the acid leaching pH value is 4.5, the acid leaching solution contains Zn 150g / l, and the acid leaching solution and high-tin lead residue are obtained; the high-tin lead residue contains Sn 0.5% and Pb 58%, and is returned to step 1) for recycling.

[0034] Example Two

[0035] A method for recycling tin in lead smelting low-grade tin-containing materials, comprising the following steps:

[0036] 1) A mixed material is prepared by mixing lead ore powder, returned dust and high-tin lead residue in a ratio of 75%:15%:10%, and the mixed material contains Pb 46% and S 16%; 9% of coal powder is further added, and the mixture is smelted in a bottom-blown furnace at 1150°C, with an oxygen material ratio of 100m 3 / t, 50m 3 / t of natural gas, Fe / SiO2 being 2.5:1, to produce primary lead, smelting residue, flue gas and dust; the primary lead contains Pb 93-98% and almost no tin, with a production rate of 85%, and is sent to a subsequent process; the flue gas is sent to an acid production process, and the dust is returned to the batching process; the smelting residue contains Pb 18%.

[0037] 2) The smelting residue in step 1) is smelted in a reduction furnace at 1200°C in a liquid state, with 14% of coal and 9m 3 / t of natural gas, to produce high-tin lead (secondary lead), slag and dust, the dust being returned to the batching process in step 1); the high-tin lead contains Pb 88%~93% and Sn >4%; and the production rate is 13%.

[0038] 3) The high-tin lead in step 2) is subjected to smelting and slagging, the temperature being 410°C, to produce high-tin high-copper lead dross and high-tin lead liquid, the high-tin lead liquid being subjected to vacuum smelting to produce crude tin and lead liquid, the lead liquid being sent to an electrolysis process; the high-tin high-copper lead dross contains Sn 3.8%, Cu 20% and Pb 60%; and the crude tin contains Sn 92%.

[0039] 4) The slag in step 2) is subjected to fuming, the fuming temperature being 1100°C, the coal amount being 22%, and the air pressure being 0.05MPa, to produce high-tin zinc suboxide, the high-tin zinc suboxide containing Sn 0.9% and Zn 65%.

[0040] 5) The high-tin high-copper lead dross in step 3) is subjected to reduction smelting, the smelting temperature is 1150°C, and high-tin lead and copper matte are produced; the high-tin lead contains Sn 1.8%, and is returned to step 3) to recycle tin; the copper matte contains Cu 50%, and is sent to a copper recovery process.

[0041] 6) The high-tin zinc suboxide in step 4) is subjected to acid leaching, the acid leaching pH value is 4.5, the acid leaching solution contains Zn 140 g / l, and the high-tin lead residue is obtained; the high-tin lead residue contains Sn 0.7% and Pb 57%, and is returned to step 1) for recycling.

[0042] Example Three

[0043] A method for recycling tin in lead smelting of low-grade tin-containing materials, comprising the following steps:

[0044] 1) A mixed material is prepared by mixing lead ore powder, returned dust and high-tin lead residue in a ratio of 80%:15%:5%, and the mixed material contains Pb 47% and S 18%; 9% of coal powder is further added, and the mixture is smelted in a bottom-blown furnace at 1100°C, with an oxygen material ratio of 90 m 3 / t, 45 m 3 / t of natural gas, Fe / SiO2 being 2:1, to produce primary lead, smelting residue, flue gas and dust; the primary lead contains Pb 93~98% and almost no tin, and the yield is 82%; the primary lead is sent to a subsequent process; the flue gas is sent to an acid production process, and the dust is returned to the material preparation process; the smelting residue contains Pb 20%.

[0045] 2) The smelting residue in step 1) is smelted in a reduction furnace in a liquid state at 1100°C, with 15% of coal and 10 m 3 / t of natural gas, to produce high-tin lead (secondary lead), slag and dust, the dust being returned to the material preparation process in step 1); the high-tin lead contains Pb 88%~93% and Sn >4%; and the yield is 15%.

[0046] 3) The high-tin lead in step 2) is subjected to melting and slagging at a temperature of 430°C, to produce high-tin high-copper lead dross and high-tin lead liquid; the high-tin lead liquid is subjected to vacuum smelting to produce crude tin and lead liquid, and the lead liquid is sent to an electrolysis process; the high-tin high-copper lead dross contains Sn 3.5%, Cu 25% and Pb 55%; and the crude tin contains Sn 91%.

[0047] 4) The slag in step 2) is subjected to fuming at a temperature of 1050°C, with 20% of coal and a wind pressure of 0.06 MPa, to produce high-tin zinc suboxide, which contains Sn 0.6% and Zn 60%.

[0048] 5) The high-tin high-copper lead dross in step 3) is subjected to reduction smelting, the smelting temperature is 1100°C, and high-tin lead and copper matte are produced; the high-tin lead contains Sn 1.5%, and is returned to step 3) to recycle tin; the copper matte contains Cu 48%, and is sent to a copper recovery process.

[0049] 6) The high-tin zinc oxide in step 4) is subjected to acid leaching, the acid leaching pH value is 4.5, the acid leaching solution contains Zn 130g / l, and the high-tin lead dross is obtained; the high-tin lead dross contains Sn 0.6% and Pb 57.5%, and is returned to step 1) for recycling.

[0050] Example Four

[0051] A method for recycling tin in lead smelting of low-grade tin-containing materials, comprising the following steps:

[0052] 1) A mixed material is prepared by mixing lead ore powder, returned dust and high-tin lead dross in a ratio of 80%:15%:5%, and the mixed material contains Pb 47% and S 18%; the mixed material is smelted in a bottom-blown furnace at 1150°C, the oxygen material ratio is 100m 3 / t, the natural gas is 50m 3 / t, Fe / SiO2 is 2:1, and smelting slag, flue gas and dust are produced without producing lead; the flue gas is sent to an acid production process, and the dust is returned to the material preparation process; the smelting slag contains Pb 57%.

[0053] 2) The smelting slag in step 1) is smelted in a reduction furnace in a liquid state at 1150°C, the coal amount is 15%, the natural gas is 20m 3 / t, and lead, slag and dust are produced; the dust is returned to the material preparation process in step 1); the lead contains Pb 90%-95% and Sn <0.3%, and the production rate is 100%.

[0054] 3) The lead in step 2) is subjected to smelting and slagging, the temperature is 430°C, and high-copper lead dross and lead liquid are produced; the lead liquid is sent to an electrolysis process; the high-copper lead dross contains Cu 27%, Pb 54% and Sn 1.1%.

[0055] 4) The slag in step 2) is subjected to fuming, the fuming temperature is 1050°C, the coal amount is 20%, and the wind pressure is 0.06MPa, and high-tin zinc oxide is produced; the high-tin zinc oxide contains Sn 0.4% and Zn 62%.

[0056] 5) The high-copper lead dross in step 3) is subjected to reduction smelting, the smelting temperature is 1100°C, and lead and copper matte are produced; the lead contains Sn 0.9%, and is subjected to oxidation to produce tin oxide slag to recycle tin; the copper matte contains Cu 48%, and is sent to a copper recovery process.

[0057] 6) The high tin zinc suboxide in step 4) is subjected to acid leaching, the acid leaching pH value is 4.5, the acid leaching solution contains Zn 130g / l, the acid leaching solution and high tin lead residue are obtained, the acid leaching solution is removed for zinc recovery process; the high tin lead residue contains Sn 0.5%, Pb 58%, and is returned to step 1) for recycling.

[0058] Compared with examples one, two and three, step 1) does not produce lead, the produced lead in step 2) contains low tin Sn<0.3%, and cannot be directly melted and slagged for vacuum smelting to produce crude tin, but can only be recycled in the lead produced by step 5) high copper lead floating residue reduction smelting, and can only be recycled in the form of tin oxide residue, prolonging the tin recycling process.

[0059] The above described examples are only preferred embodiments of the present application, and are only used to explain the present application, and are not intended to limit the scope of the present application. For those skilled in the art, of course, other embodiments can be easily made by substitution or change based on the technical content disclosed in the present specification, and therefore, any changes and improvements made on the principles of the present application shall be included in the scope of the present application.

Claims

1. A method for recovering tin from low-grade tin-containing materials in lead smelting, characterized in that, Includes the following steps: 1) Mix lead ore powder, returned flue dust and high-tin lead slag into a mixture, then add pulverized coal, and smelt in a bottom-blown furnace at 1000~1250℃ to produce primary lead, smelting slag, flue gas and flue dust; the primary lead is sent to the next process, the flue gas is sent to acid production, and the flue dust is returned to the batching process. 2) The smelting slag from step 1) is fed into the reduction furnace in liquid form and smelted at 1000~1200℃ to produce high tin lead, slag and flue dust. The flue dust is returned to the batching process in step 1). 3) Melt and remove the high-tin lead from step 2) to produce high-tin, high-copper, and high-lead slag and high-tin lead liquid. The high-tin lead liquid is then vacuum smelted to produce crude tin and lead liquid. The lead liquid is then sent to the electrolysis process. 4) The slag from step 2) is fumed to produce high-tin zinc oxide; 5) Reduce and smelt the high-tin, high-copper, and high-lead slag from step 3) to produce high-tin lead and matte; return the high-tin lead to step 3) for repeated tin recovery, and send the matte to the copper recovery process. 6) The high-tin zinc oxide from step 4) is acid-leached to obtain acid leaching solution and high-tin lead slag. The acid leaching solution is sent to the zinc recovery process, and the high-tin lead slag is returned to step 1) for recycling.

2. The method according to claim 1, characterized in that, The mass percentages of lead ore powder, returned flue dust, and high-tin lead slag in the mixture in step 1) are as follows: 70~85%, 10~20%, and 5~10%, respectively. The mixture contains 20~50% Pb and 10~20% S. The amount of coal powder added is 1~10% of the mixture.

3. The method according to claim 1, characterized in that, In step 3), the temperature for melting and removing slag is 400~450℃.

4. The method according to claim 1, characterized in that, In step 4), the temperature during fumigation is 1000~1150℃.

5. The method according to claim 1, characterized in that, In step 5), the temperature during reduction smelting is 1000~1200℃.

6. The method according to claim 1, characterized in that, In step 6), the pH value during acid leaching is 3.5~4.5.

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