Process for producing lead-antimony alloy by using secondary lead

Abstract

The invention discloses a process for producing a lead-antimony alloy by using secondary lead, and relates to the technical field of lead-antimony alloy production. The process adopts a lead-antimony alloy production system for production, and comprises the following specific steps: (1) smelting: putting a regenerated lead block into a lead smelting pot, and smelting at 440-500 DEG C to obtain crude lead liquid; (2) refining: adding a first refining agent into the crude lead liquid, stirring to react, fishing out slag, cooling to 300-350 DEG C, adding a second refining agent, stirring to react, and fishing out slag to obtain pure lead liquid; and (3) alloy preparation: heating the pure lead liquid to 500-550 DEG C, adding antimony and copper, stirring until the antimony and copper are completely molten, sampling and analyzing, cooling to 450-480 DEG C when the antimony and copper meet the product requirements, adding tin, stirring until the antimony and copper are completely molten, sampling and analyzing, cooling to 400-420 DEG C when the tin meets the product requirements, adding selenium, stirring until the tin is completely molten, sampling and analyzing, discharging lead and casting ingots when the selenium meets the product requirements, and cooling to the room temperature. And the lead-antimony alloy is obtained. The process and the system are high in automation degree, the refining efficiency can be improved, and pollution is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of lead-antimony alloy production, and in particular to a process for producing lead-antimony alloy by utilizing recycled lead. Background Art

[0002] Lead-antimony alloy is a lead alloy containing antimony for manufacturing lead-acid battery grids and conductive parts. Compared with pure lead, it has a lower melting point, good fluidity in the molten state, easy casting and high hardness after solidification. In order to reduce the gas precipitation during battery charging, reduce self-discharge and improve corrosion resistance, the antimony content has been gradually reduced from the traditional 5%-7% to about 2% or even lower. At the same time, a small amount of other ingredients such as tin, arsenic, sulfur, selenium and copper are selectively added to improve the physical and chemical properties of the alloy.

[0003] Recycled lead is a crude lead material that is extracted and recycled from waste lead-acid batteries and lead-containing waste through pyrometallurgical or hydrometallurgical processes. In addition to containing about 96% lead, it also contains impurities such as Ag, Cu, Bi, As, Sb, Sn, Zn, Fe, Cd, and Ni. The use of recycled lead to prepare lead-antimony alloy can be a good way to recycle waste. At present, the use of recycled lead as a raw material to prepare lead-antimony alloy mainly involves first melting the recycled lead, then refining and removing impurities, and after the purity of the lead liquid is increased to more than 99.99%, antimony and other metal elements are added to make it. However, the above preparation process has the following problems: First, the refining and impurity removal process is complicated, the refining efficiency is not high, it takes a long time to obtain high-purity lead liquid, and the impurity removal effect is poor; second, in the impurity removal process, long-term and high-intensity stirring will accelerate the volatilization of lead, resulting in large lead losses; third, the smelting and refining process will produce a large amount of dust, lead vapor and other harmful gases. At present, dust extraction fans and spray circulating water are turned on to reduce pollution, but the dust removal effect is not good, which seriously affects the physical and mental health of on-site operators; fourth, the degree of production automation is low. At present, there is no automated lead-antimony alloy production system that integrates automatic stirring and automatic dust removal.

[0004] In summary, the present invention provides a process for producing lead-antimony alloy using recycled lead. Summary of the invention

[0005] In view of the above shortcomings, the present invention provides a process for producing lead-antimony alloy using recycled lead, which solves the problems of low refining efficiency, high pollution and low automation. The specific technical solution is as follows:

[0006] A process for producing lead-antimony alloy using recycled lead, wherein the process adopts a lead-antimony alloy production system for production, and specifically comprises the following steps:

[0007] (1) Smelting: Place the recycled lead block into a lead melting pot and melt it into crude lead liquid at 440-500℃;

[0008] (2) Refining: adding 0.5-1% of the first refining agent to the crude lead liquid, stirring for 5-10 minutes, reacting for 20-30 minutes, removing the slag, then cooling to 300-350° C., adding 0.2-0.5% of the second refining agent, stirring for 5-10 minutes, reacting for 20-30 minutes, removing the slag, and obtaining pure lead liquid;

[0009] (3) Alloy preparation: The pure lead liquid is heated to 500-550°C, antimony and copper are added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When antimony and copper meet the product requirements, the temperature is lowered to 450-480°C, tin is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When tin meets the product requirements, the temperature is lowered to 400-420°C, selenium is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When selenium meets the product requirements, lead is added and an ingot is cast to obtain the lead-antimony alloy.

[0010] Furthermore, the first refining agent comprises the following raw materials in parts by weight: 30-40 parts of sodium nitrate, 5-10 parts of sodium chloride, 6-15 parts of sodium hydroxide, 1-3 parts of zinc, 0.5-2.5 parts of magnesium oxide, 3-9 parts of zinc chloride, 1-5 parts of calcium fluoride and 1-10 parts of sodium borate.

[0011] Furthermore, the second refining agent comprises the following raw materials in parts by weight: 15-25 parts of magnesium powder, 20-30 parts of sulfur, 0.5-2.5 parts of magnesium oxide, 3-9 parts of zinc chloride, 1-5 parts of calcium fluoride and 1-10 parts of sodium borate.

[0012] Further, the lead-antimony alloy production system includes: a lead melting pot, a stirrer, a variable frequency motor, a PLC controller, a thermocouple sensor, a first dust sensor, a second dust sensor, an induced draft fan, a liquid infusion pipe, an electric liquid inlet valve, an alkali liquid pool, a first pipeline, a second pipeline, a third pipeline, a bag dust collector, a spray tower and a smoke flush;

[0013] The lead melting pot is connected to the bag dust collector through a first pipeline, the bag dust collector is connected to the spray tower through a second pipeline, and the spray tower is connected to the smoke shower through a third pipeline; an electric liquid inlet valve is provided on the liquid infusion pipe, one end of the liquid infusion pipe is connected to the alkali liquid pool, and the other end is connected to the spray tower; the first pipeline, the second pipeline, and the third pipeline are all provided with induced draft fans;

[0014] The signal output end of the thermocouple sensor is electrically connected to the PLC controller; the signal output ends of the first dust sensor and the second dust sensor are electrically connected to the PLC controller respectively; the induced draft fan on the first pipeline is electrically connected to the PLC controller; the electric liquid inlet valve is electrically connected to the PLC controller; the PLC controller is connected to the output shaft of the variable frequency motor, and the variable frequency motor is connected to the transmission shaft on the agitator;

[0015] The stirrer and the thermocouple sensor are arranged inside the lead melting pot; the first dust sensor is arranged above the opening of the lead melting pot; and the second dust sensor is arranged at the bottom of the spray tower.

[0016] Furthermore, the bag dust collector includes a dust box and an ash hopper; the dust box is provided with a first air inlet at the bottom, a first air outlet at the top, and a plurality of dust bags inside; a dust reduction partition is provided between the dust box and the ash hopper, and the dust reduction partition is provided with a through hole.

[0017] Furthermore, a dust removal ring is provided on the dust removal bag, bristles are provided on the inner wall of the dust removal ring, and the bristles just contact the outer wall of the dust removal bag. A telescopic rod is provided on the side wall of the dust removal ring, and the telescopic rod extends to the outside of the top of the dust removal box, and can drive the dust removal ring to move up and down by pulling up and down.

[0018] Furthermore, the inner wall surface of the dust removal box and the ash hopper is coated with a ceramic coating, which can improve the corrosion resistance and wear resistance of the inner wall and make the interior more slippery, so that dust can slide off easily without clogging.

[0019] Furthermore, the spray tower is provided with a buffer chamber, a primary alkaline spray chamber, and a secondary alkaline spray chamber from bottom to top, and spray partitions are respectively provided between the buffer chamber, the primary alkaline spray chamber, and the secondary alkaline spray chamber, and the spray partitions are provided with through holes; a second air inlet is provided on the side wall of the buffer chamber, and a liquid outlet is provided at the bottom of the buffer chamber; spray pipes are provided on the side walls of the primary alkaline spray chamber and the secondary alkaline spray chamber, and nozzles are provided on the spray pipes, and the spray pipes are connected to the infusion pipe; packing layers are provided in the primary alkaline spray chamber and the secondary alkaline spray chamber, and the packing layers are ball rings; a wire mesh demister is provided above the secondary alkaline spray chamber, and a second air outlet is provided at the top of the secondary alkaline spray chamber.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention reduces the stirring intensity of the smelting and refining processes, shortens the refining time, reduces the loss of lead, improves the refining and impurity removal efficiency, obtains pure lead liquid with a purity of 99.99%, and realizes the automation of stirring and dust removal, saving manpower.

[0022] 2. The sodium nitrate, sodium chloride, sodium hydroxide and zinc in the first refining agent of the present invention can remove antimony, tin, arsenic, iron and silver in the crude lead liquid, and the magnesium powder and sulfur in the second refining agent can remove copper and bismuth in the crude lead liquid. The magnesium oxide, zinc chloride, calcium fluoride and sodium borate in the first refining agent and the second refining agent cooperate with each other and enhance the efficiency, thereby reducing the viscosity of the crude lead liquid and increasing the fluidity, so that the refining agent can be quickly spread in the crude lead liquid and quickly combine and react with the components in the crude lead liquid, so as to achieve the purpose of fast and efficient impurity removal and obtain lead with higher purity. At the same time, the low viscosity of the crude lead liquid can reduce the stirring speed and stirring time, reduce the higher volatilization of lead due to high stirring intensity, and thus reduce the loss of lead.

[0023] 3. The lead-antimony alloy production system of the present invention uses a PLC controller to intelligently control the agitator, thermocouple sensor, first industrial dust sensor, second industrial dust sensor, induced draft fan and electric liquid inlet valve at the same time, thereby realizing automatic stirring and automatic and efficient dust removal during the smelting and refining processes, and improving production efficiency.

[0024] 4. The dust removal ring on the dust bag of the present invention can quickly clean the dust attached to the dust bag, thereby improving the dust removal efficiency. At the same time, the inner wall surface of the dust box and the ash hopper is coated with a layer of ceramic coating, which not only improves its corrosion resistance and wear resistance, but also makes the interior more slippery, so that dust can slide easily and is not easy to be blocked. The spray tower of the present invention improves the removal effect of pollutants by setting a primary alkaline spray chamber, a secondary alkaline spray chamber, and a packing layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0026] Figure 1 It is a structural schematic diagram of the lead-antimony alloy production system of the present invention;

[0027] Figure 2 A top view of the dust removal ring and dust removal bag of the present invention;

[0028] Main figure marks: 1-lead melting pot, 2-agitator, 3-frequency conversion motor, 4-PLC controller, 5-thermocouple sensor, 6-first dust sensor, 7-second dust sensor, 8-induced draft fan, 9-infusion pipe, 10-electric inlet valve, 11-alkali liquid pool, 12-first pipeline, 13-second pipeline, 14-third pipeline, 15-bag dust collector, 151-dust removal box, 152-ash hopper, 153-first air inlet, 154-first air outlet, 155 -dust removal bag, 156-dust reduction baffle, 157-ash removal ring, 158-telescopic rod, 159-brush, 16-spray tower, 161-buffer chamber, 162-primary alkaline spray chamber, 163-secondary alkaline spray chamber, 164-spray baffle, 165-second air inlet, 166-liquid outlet, 167-spray pipe, 168-spray head, 169-infusion pipe, 1610-packing layer, 1611-wire mesh demister, 1612-second air outlet and 17-smoke flushing. DETAILED DESCRIPTION

[0029] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0030] Example 1

[0031] like Figure 1 As shown, the lead-antimony alloy production system of this embodiment includes: a lead melting pot 1, a bag dust collector 15, a spray tower 16 and a smoke blast 17; the lead melting pot 1 is connected to the bag dust collector 15 through a first pipe 12, the bag dust collector 15 is connected to the spray tower 16 through a second pipe 13, the spray tower 16 is connected to the smoke blast 17 through a third pipe 14, and the first pipe 12, the second pipe 13, and the third pipe 14 are all provided with an induced draft fan 8. The dust and waste gas generated by the lead melting pot 1 during the smelting and refining process enter the bag dust collector 15 through the first pipe 12 to remove dust particles, and then the waste gas enters the spray tower 16 through the second pipe 13, the toxic gas is removed, and the clean gas obtained after being treated by the bag dust collector 15 and the spray tower 16 enters the smoke blast 17 through the third pipe 14 and is discharged.

[0032] Specifically, a stirrer 2 and a thermocouple sensor 5 are provided inside the lead melting pot 1, and a first dust sensor 6 is provided above the opening of the lead melting pot 1. The thermocouple sensor 5 is used to detect the temperature inside the lead melting pot 1, and the first dust sensor 6 is an industrial sensor that can detect the concentration of dust and exhaust gas above the lead melting pot 1.

[0033] Specifically, the bag filter 15 includes a dust box 151 and an ash hopper 152; the dust box 151 is provided with a first air inlet 153 at the bottom, a first air outlet 154 at the top, and a plurality of dust bags 155 inside; a dust reduction baffle 156 is provided between the dust box 151 and the ash hopper 152, and a through hole is provided on the dust reduction baffle 156. Dust and waste gas enter the dust box 151 through the first air inlet 153, and the dust particles are filtered by the dust bags 155 in the dust box 151, and the dust falls on the ash hopper 152, and the waste gas enters the spray tower 16 through the first air outlet 154 for further treatment.

[0034] Furthermore, if Figure 2 As shown, a dust removal ring 157 is sleeved on the dust removal bag 155, and bristles 159 are provided on the inner wall of the dust removal ring 157, and the bristles 159 just contact the outer wall of the dust removal bag 155. A telescopic rod 158 is provided on the side wall of the dust removal ring 157, and the telescopic rod 158 extends to the outside of the top of the dust removal box 151, and can drive the dust removal ring 157 to move up and down by pulling up and down. When a large amount of dust accumulates on the dust removal bag 155, the telescopic rod 158 can be pulled to drive the dust removal ring 157 to move up and down outside the dust removal bag 155, and the bristles 159 on the dust removal ring 157 can clean the dust attached to the dust removal bag 155, thereby improving the dust removal efficiency.

[0035] Furthermore, the inner wall surfaces of the dust removal box 151 and the ash hopper 152 are coated with a ceramic coating, which can improve the corrosion resistance and wear resistance of the inner wall and make the interior smoother, so that dust can easily slide off without clogging.

[0036] Specifically, the spray tower 16 is provided with a buffer chamber 161, a primary alkaline spray chamber 162, and a secondary alkaline spray chamber 163 from bottom to top; an alkali solution pool 11, a liquid infusion pipe 9, and an electric liquid inlet valve 10 are also provided near the spray tower 16, and the electric liquid inlet valve 10 is arranged on the liquid infusion pipe 9, one end of the liquid infusion pipe 9 is connected to the alkali solution pool 11, and the other end is connected to the spray tower 16; spray partitions 164 are respectively provided between the buffer chamber 161, the primary alkaline spray chamber 162, and the secondary alkaline spray chamber 163, and the spray partitions 164 are provided with through holes; a second air inlet 165 is provided on the side wall of the buffer chamber 161, and the buffer chamber 161 is provided with a second air inlet 165. A liquid outlet 166 is provided at the bottom of the flushing chamber 161, and a second dust sensor 7 is provided on the side wall of the buffer chamber 161; a spray pipe 167 is provided on the side wall of the primary alkaline spray chamber 162 and the secondary alkaline spray chamber 163, and the spray pipe 167 is connected to the infusion pipe 169, and a nozzle 168 is provided on the spray pipe 167; a packing layer 1610 is provided in the primary alkaline spray chamber 162 and the secondary alkaline spray chamber 163, and the packing layer 1610 is a ball ring; a wire mesh demister 1611 is provided above the secondary alkaline spray chamber 163, and a second air outlet 1612 is provided on the top of the secondary alkaline spray chamber 163. The waste gas with dust removed enters the buffer chamber 161 through the second air inlet 165, and enters the primary alkaline spray chamber 162 and the secondary alkaline spray chamber 163 through the spray partition 164. The nozzle 168 sprays alkali solution to remove polluted gas in the waste gas. The ball ring in the packing layer 1610 can make the waste gas and the alkali solution contact evenly and prolong the contact time to make the removal effect better. The wire mesh demister 1611 can quickly separate the treated gas and the alkali solution, and the alkali solution falls and is recovered through the liquid outlet 166. The treated gas enters the third pipe 14 through the second air outlet 1612 and enters the smoke 17 for discharge. In addition, the second dust sensor 7 is an industrial dust sensor for detecting the treated gas.

[0037] Specifically, the lead-antimony alloy production system of this embodiment further includes a PLC controller 4 and a variable frequency motor 3, the signal output end of the thermocouple sensor 5 is electrically connected to the PLC controller 4; the signal output ends of the first dust sensor 6 and the second dust sensor 7 are electrically connected to the PLC controller 4 respectively; the induced draft fan 8 on the first pipeline 12 is electrically connected to the PLC controller 4; the electric liquid inlet valve 10 is electrically connected to the PLC controller 4; the PLC controller 4 is connected to the output shaft of the variable frequency motor 3, and the variable frequency motor 3 is connected to the transmission shaft on the stirrer 2. The PLC controller 4 can automatically adjust the stirring intensity, stirring time and stirring period of the stirrer 2 through the detection data of the thermocouple sensor 5; the PLC controller 4 can automatically adjust the opening or closing of the induced draft fan 8 on the first pipeline 12 through the detection data of the first dust sensor 6. When the first dust sensor 6 detects pollutants, the induced draft fan 8 is opened, otherwise it is closed. The PLC controller 4 can automatically adjust the opening or closing of the electric liquid inlet valve 10 through the detection data of the second dust sensor 7. When the second dust sensor 7 detects pollutants, the electric liquid inlet valve 10 opens, otherwise it closes, thus realizing automatic control without manual processing and reducing labor costs.

[0038] Example 2

[0039] The process of producing lead-antimony alloy by using recycled lead in this embodiment is carried out by using the lead-antimony alloy production system of embodiment 1, and specifically comprises the following steps:

[0040] (1) Smelting: Place the recycled lead block into a lead melting pot and melt it into crude lead liquid at 440°C;

[0041] (2) Refining: add 0.5% of the first refining agent to the crude lead liquid, stir for 10 minutes, react for 30 minutes, remove the slag, then cool to 300°C, add 0.2% of the second refining agent, stir for 10 minutes, react for 30 minutes, remove the slag, and obtain pure lead liquid; the first refining agent includes the following raw materials in parts by weight: 30 parts of sodium nitrate, 5 parts of sodium chloride, 6 parts of sodium hydroxide, 1 part of zinc, 0.5 parts of magnesium oxide, 3 parts of zinc chloride, 1 part of calcium fluoride and 1 part of sodium borate. The second refining agent includes the following raw materials in parts by weight: 15 parts of magnesium powder, 20 parts of sulfur, 0.5 parts of magnesium oxide, 3 parts of zinc chloride, 1 part of calcium fluoride and 1 part of sodium borate.

[0042] (3) Alloy preparation: The pure lead liquid is heated to 500°C, antimony and copper are added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When antimony and copper meet the product requirements, the temperature is lowered to 450°C, tin is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When tin meets the product requirements, the temperature is lowered to 400°C, selenium is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When selenium meets the product requirements, lead is added and an ingot is cast to obtain the lead-antimony alloy.

[0043] In the above process, the crude lead liquid is automatically stirred once when the temperature is 440°C, the stirring speed is 50rpm, and the stirring time is 10min; the crude lead liquid is automatically stirred once when the temperature is 300°C, the stirring speed is 100rpm, and the stirring time is 10min; the pure lead liquid is automatically stirred once when the temperature is 500°C, 450°C, and 400°C, respectively, the stirring speed is 50rpm, and the stirring time is 10min. The waste gas dust generated in the above process is cleaned by the bag dust collector and spray tower in the lead-antimony alloy production system.

[0044] Example 3

[0045] The process of producing lead-antimony alloy by using recycled lead in this embodiment is carried out by using the lead-antimony alloy production system of embodiment 1, and specifically comprises the following steps:

[0046] (1) Smelting: Place the recycled lead block into a lead melting pot and melt it into crude lead liquid at 500°C;

[0047] (2) Refining: add 1% of the first refining agent to the crude lead liquid, stir for 5 minutes, react for 20 minutes, remove the slag, then cool to 350°C, add 0.5% of the second refining agent, stir for 5 minutes, react for 20 minutes, remove the slag, and obtain pure lead liquid; the first refining agent includes the following raw materials in parts by weight: 40 parts of sodium nitrate, 10 parts of sodium chloride, 15 parts of sodium hydroxide, 3 parts of zinc, 2.5 parts of magnesium oxide, 9 parts of zinc chloride, 5 parts of calcium fluoride and 10 parts of sodium borate. The second refining agent includes the following raw materials in parts by weight: 25 parts of magnesium powder, 30 parts of sulfur, 2.5 parts of magnesium oxide, 9 parts of zinc chloride, 5 parts of calcium fluoride and 10 parts of sodium borate.

[0048] (3) Alloy preparation: The pure lead liquid is heated to 550°C, antimony and copper are added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When antimony and copper meet the product requirements, the temperature is lowered to 480°C, tin is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When tin meets the product requirements, the temperature is lowered to 420°C, selenium is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When selenium meets the product requirements, lead is added and an ingot is cast to obtain the lead-antimony alloy.

[0049] In the above process, the crude lead liquid is automatically stirred once when the temperature is 500℃, the stirring speed is 100rpm, and the stirring time is 5min; the crude lead liquid is automatically stirred once when the temperature is 350℃, the stirring speed is 150rpm, and the stirring time is 5min; the pure lead liquid is automatically stirred once when the temperature is 550℃, 480℃, and 420℃, the stirring speed is 100rpm, and the stirring time is 5min. The waste gas dust generated in the above process is cleaned by the bag dust collector and spray tower in the lead-antimony alloy production system.

[0050] Example 4

[0051] The process of producing lead-antimony alloy by using recycled lead in this embodiment is carried out by using the lead-antimony alloy production system of embodiment 1, and specifically comprises the following steps:

[0052] (1) Smelting: Place the recycled lead block into a lead melting pot and melt it into crude lead liquid at 480°C;

[0053] (2) Refining: add 0.8% of the first refining agent to the crude lead liquid, stir for 7 minutes, react for 25 minutes, remove the slag, then cool to 330°C, add 0.4% of the second refining agent, stir for 6 minutes, react for 25 minutes, remove the slag, and obtain pure lead liquid; the first refining agent includes the following raw materials in parts by weight: 35 parts of sodium nitrate, 8 parts of sodium chloride, 11 parts of sodium hydroxide, 2 parts of zinc, 1 part of magnesium oxide, 7 parts of zinc chloride, 3 parts of calcium fluoride and 8 parts of sodium borate. The second refining agent includes the following raw materials in parts by weight: 20 parts of magnesium powder, 25 parts of sulfur, 1 part of magnesium oxide, 7 parts of zinc chloride, 3 parts of calcium fluoride and 8 parts of sodium borate.

[0054] (3) Alloy preparation: The pure lead liquid is heated to 530°C, antimony and copper are added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When antimony and copper meet the product requirements, the temperature is lowered to 460°C, tin is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When tin meets the product requirements, the temperature is lowered to 410°C, selenium is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When selenium meets the product requirements, lead is added and an ingot is cast to obtain the lead-antimony alloy.

[0055] In the above process, the crude lead liquid is automatically stirred once when the temperature is 480°C, the stirring speed is 80rpm, and the stirring time is 7min; the crude lead liquid is automatically stirred once when the temperature is 330°C, the stirring speed is 120rpm, and the stirring time is 6min; the pure lead liquid is automatically stirred once when the temperature is 530°C, 460°C, and 410°C, the stirring speed is 80rpm, and the stirring time is 7min. The waste gas dust generated in the above process is cleaned by the bag dust collector and spray tower in the lead-antimony alloy production system.

[0056] Comparative Example 1

[0057] The refining agent used in this comparative example is a traditional refining agent, that is, it does not contain magnesium oxide, zinc chloride, calcium fluoride and sodium borate. Other processes and equipment are the same as those in Example 2.

[0058] Comparative Example 2

[0059] The refining agent used in this comparative example does not contain magnesium oxide and zinc chloride, and other processes and equipment are the same as those in Example 2.

[0060] Comparative Example 3

[0061] The refining agent used in this comparative example does not contain calcium fluoride and sodium borate, and other processes and equipment are the same as those in Example 2.

[0062] The recycled lead used in the above embodiments and comparative examples is from the same batch, and the mass fraction of lead is 96.5%. After the refining, the purity of the lead liquids in embodiments 2 to 4 and comparative examples 1 to 3 is respectively tested, and the results are shown in Table 1:

[0063] Table 1 Comparison of chemical composition of each group of lead liquid

[0064]

[0065] The above table shows that magnesium oxide, zinc chloride, calcium fluoride and sodium borate in the refining agent of the present invention can improve the purity of lead liquid and have a coordinated and synergistic effect.

[0066] In summary, the process and system of the present invention have a high degree of automation, can improve refining efficiency and reduce pollution.

[0067] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A process for producing lead-antimony alloy using recycled lead, characterized in that: The process is to use a lead-antimony alloy production system for production, and specifically includes the following steps: (1) Smelting: Place the recycled lead block into a lead melting pot and melt it into crude lead liquid at 440-500°C; (2) Refining: adding 0.5-1% of the first refining agent to the crude lead liquid, stirring for 5-10 minutes, reacting for 20-30 minutes, removing the slag, then cooling to 300-350° C., adding 0.2-0.5% of the second refining agent, stirring for 5-10 minutes, reacting for 20-30 minutes, removing the slag, and obtaining pure lead liquid; (3) Alloy preparation: The pure lead liquid is heated to 500-550°C, antimony and copper are added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When antimony and copper meet the product requirements, the temperature is lowered to 450-480°C, tin is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When tin meets the product requirements, the temperature is lowered to 400-420°C, selenium is added, and the mixture is stirred until completely melted. Then, a sample is taken and a spectral analysis is performed on the sample. When selenium meets the product requirements, lead is added and an ingot is cast to obtain the lead-antimony alloy.

2. A process for producing lead-antimony alloy using recycled lead according to claim 1, characterized in that: The first refining agent comprises the following raw materials in parts by weight: 30-40 parts of sodium nitrate, 5-10 parts of sodium chloride, 6-15 parts of sodium hydroxide, 1-3 parts of zinc, 0.5-2.5 parts of magnesium oxide, 3-9 parts of zinc chloride, 1-5 parts of calcium fluoride and 1-10 parts of sodium borate.

3. The process for producing lead-antimony alloy using recycled lead according to claim 1, characterized in that: The second refining agent comprises the following raw materials in parts by weight: 15-25 parts of magnesium powder, 20-30 parts of sulfur, 0.5-2.5 parts of magnesium oxide, 3-9 parts of zinc chloride, 1-5 parts of calcium fluoride and 1-10 parts of sodium borate.

4. A process for producing lead-antimony alloy using recycled lead according to claim 1, characterized in that: The lead-antimony alloy production system comprises: a lead melting pot, a stirrer, a variable frequency motor, a PLC controller, a thermocouple sensor, a first dust sensor, a second dust sensor, an induced draft fan, a liquid infusion pipe, an electric liquid inlet valve, an alkali liquid pool, a first pipeline, a second pipeline, a third pipeline, a bag dust collector, a spray tower and a smoke flushing; The lead melting pot is connected to the bag dust collector through a first pipeline, the bag dust collector is connected to the spray tower through a second pipeline, and the spray tower is connected to the smoke shower through a third pipeline; an electric liquid inlet valve is provided on the liquid infusion pipe, one end of the liquid infusion pipe is connected to the alkali liquid pool, and the other end is connected to the spray tower; the first pipeline, the second pipeline, and the third pipeline are all provided with induced draft fans; The signal output end of the thermocouple sensor is electrically connected to the PLC controller; the signal output ends of the first dust sensor and the second dust sensor are electrically connected to the PLC controller respectively; the induced draft fan on the first pipeline is electrically connected to the PLC controller; the electric liquid inlet valve is electrically connected to the PLC controller; the PLC controller is connected to the output shaft of the variable frequency motor, and the variable frequency motor is connected to the transmission shaft on the agitator; The stirrer and the thermocouple sensor are arranged inside the lead melting pot; the first dust sensor is arranged above the opening of the lead melting pot; and the second dust sensor is arranged at the bottom of the spray tower.

5. A process for producing lead-antimony alloy using recycled lead according to claim 4, characterized in that: The bag dust collector comprises a dust box and an ash hopper; the dust box is provided with a first air inlet at the bottom, a first air outlet at the top, and a plurality of dust bags inside; a dust reduction partition is provided between the dust box and the ash hopper, and the dust reduction partition is provided with a through hole.

6. A process for producing lead-antimony alloy using recycled lead according to claim 5, characterized in that: A dust removal ring is provided on the dust removal bag, and bristles are provided on the inner wall of the dust removal ring. The bristles just contact the outer wall of the dust removal bag. A telescopic rod is provided on the side wall of the dust removal ring. The telescopic rod extends to the outside of the top of the dust removal box and can drive the dust removal ring to move up and down by pulling up and down.

7. A process for producing lead-antimony alloy using recycled lead according to claim 5, characterized in that: The inner wall surfaces of the dust removal box and the ash hopper are coated with a layer of ceramic coating.

8. The process for producing lead-antimony alloy using recycled lead according to claim 4, characterized in that: The spray tower is provided with a buffer chamber, a primary alkaline spray chamber, and a secondary alkaline spray chamber in sequence from bottom to top, and spray partitions are respectively provided between the buffer chamber, the primary alkaline spray chamber, and the secondary alkaline spray chamber, and the spray partitions are provided with through holes; a second air inlet is provided on the side wall of the buffer chamber, and a liquid outlet is provided at the bottom of the buffer chamber; spray pipes are provided on the side walls of the primary alkaline spray chamber and the secondary alkaline spray chamber, and nozzles are provided on the spray pipes, and the spray pipes are connected to the infusion pipe; packing layers are provided in the primary alkaline spray chamber and the secondary alkaline spray chamber, and the packing layers are ball rings; a wire mesh demister is provided above the secondary alkaline spray chamber, and a second air outlet is provided at the top of the secondary alkaline spray chamber.

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