Zinc pyrometallurgy valuable metal recovery system

Abstract

The utility model discloses a system for recovering valuable metals in zinc pyrometallurgy, which comprises a smelting device, the smelting device is provided with an oxidation smelting area and a reduction smelting area, the bottom of the oxidation smelting area is communicated with the bottom of the reduction smelting area, and zinc concentrate is smelted in the oxidation smelting area and is oxidized and desulfurized. Slag generated by smelting in the oxidation smelting area flows into the reduction smelting area to be reduced, the oxidation smelting area is provided with a first smoke outlet and a first metal discharging opening, and the reduction smelting area is provided with a second smoke outlet, a second metal discharging opening and a slag discharging opening. The system further comprises a first processing unit and a second processing unit. The first treatment unit is connected with the first smoke outlet and used for recycling valuable metal in smoke exhausted from the oxidation smelting area, and the second treatment unit is connected with the second smoke outlet and used for recycling valuable metal in smoke exhausted from the reduction smelting area. According to the utility model, short-process zinc pyrometallurgy can be realized, the material preparation process is simplified, and the metal recovery rate is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of metal smelting, and particularly relates to a pyrometallurgical zinc smelting and valuable metal recovery system. BACKGROUND

[0002] Zinc smelting is mainly divided into pyrometallurgical smelting and hydrometallurgical smelting, the hydrometallurgical zinc smelting technology process is long, and leaching residues and iron residues generated are dangerous wastes, which need to be harmlessly treated, energy consumption is relatively high and new pollution is caused. Pyrometallurgical smelting is mainly divided into blast furnace zinc smelting, vertical tank zinc smelting and electric furnace zinc smelting, the pyrometallurgical zinc smelting technology in the related art has a complex preparation process and low metal recovery rate. CONTENT OF UTILITY MODEL

[0003] The utility model is made based on the discovery and realization of the inventor to the following facts and problems:

[0004] The inventor realizes that the blast furnace zinc smelting can only treat lead-zinc mixed ore with a certain lead-zinc ratio, the raw material must be sintered before being put into the furnace, the final residue of the blast furnace contains 5% to 7% of zinc, the residue contains high zinc, and the recovery rate of valuable metals such as zinc is low; in the vertical tank zinc smelting, the zinc concentrate must be roasted and formed into pellets before being put into the furnace, the raw material has a high composition requirement and the preparation process is complex, the final residue contains 5% to 10% of zinc, and the recovery rate of valuable metals such as zinc, copper, gold and silver is relatively low; in the electric furnace zinc smelting, the zinc concentrate needs to be roasted before being put into the furnace, the atmosphere and temperature in the furnace need to be controlled during the smelting process after being put into the furnace, the bed capacity and reduction efficiency are low, the final residue contains 3% to 6% of zinc, the recovery rate of copper enrichment to bottom iron is relatively low, in addition, the pyrometallurgical smelting has small single series production capacity, which cannot meet the requirements of modern large-scale industrial production.

[0005] The inventor also realizes that the hydrometallurgical smelting is mainly through sulfuric acid system leaching of zinc-containing oxides, the zinc concentrate must be roasted before being leached, zinc sulfate solution is obtained, cathode zinc sheet is obtained through liquid purification and electrolytic deposition, and Zn99.995% zinc ingot is obtained through zinc casting. However, the process has many procedures, the process is complex, the investment is huge, the energy consumption is relatively high, and the direct current power consumption of a ton of zinc in the single electrode deposition procedure reaches 3000 kWh. More importantly, a large amount of leaching residue and iron residue is generated in the hydrometallurgical process, the output rate exceeds 50%, and all the residues are dangerous wastes, which need to be harmlessly treated, causing a large amount of energy consumption and new pollution. The hydrometallurgical process is divided into conventional leaching process and hot acid leaching process, and the conventional leaching process accounts for 70% to 80% of the total production capacity, the recovery rate of copper is generally 30% to 40%, the best level can only reach 50%, the recovery rates of gold and silver are similar, and are about 60%, and the recovery rate of valuable metals is relatively low.

[0006] The utility model aims to at least solve one of the technical problems in the related art to some extent.

[0007] Therefore, the zinc smelting and valuable metal recovery system can realize short-process zinc smelting, simplify the material preparation process, and improve the metal recovery rate.

[0008] The zinc smelting and valuable metal recovery system comprises a smelting device.

[0009] The smelting device has an oxidation smelting zone and a reduction smelting zone, the bottom of the oxidation smelting zone and the bottom of the reduction smelting zone are communicated, zinc concentrate is smelted and oxidized and desulfurized in the oxidation smelting zone, and the molten slag generated by smelting in the oxidation smelting zone flows into the reduction smelting zone for reduction.

[0010] The oxidation smelting zone has a first smoke outlet and a first metal discharge port, and the reduction smelting zone has a second smoke outlet, a second metal discharge port and a slag discharge port.

[0011] The zinc smelting and valuable metal recovery system further comprises:

[0012] a first processing unit and a second processing unit.

[0013] The first processing unit is connected with the first smoke outlet, the first processing unit is used for recovering valuable metals in the flue gas discharged from the oxidation smelting zone, the second processing unit is connected with the second smoke outlet, and the second processing unit is used for recovering valuable metals in the flue gas discharged from the reduction smelting zone.

[0014] The zinc smelting and valuable metal recovery system can realize short-process zinc smelting, simplify the material preparation process, and improve the metal recovery rate.

[0015] In some embodiments, the oxidation smelting zone has a first working condition and a second working condition.

[0016] In the first working condition, the temperature in the oxidation smelting zone is 1100 DEG C to 1300 DEG C, and the oxygen-material ratio in the oxidation smelting zone is 100 Nm 3 / t to 250 Nm 3 / t.

[0017] In the second working condition, the temperature in the oxidation smelting zone is 1350 DEG C to 1550 DEG C, and the oxygen-material ratio in the oxidation smelting zone is 300 Nm 3 / t to 500 Nm 3 / t.

[0018] In some embodiments, a first lance is further included, the oxidation smelting zone has a first spray port, and the first lance is connected with the first spray port to spray oxygen into the oxidation smelting zone.

[0019] And / or, the oxidizing smelting zone further has a first feeding port for feeding zinc concentrate and flux into the oxidizing smelting zone.

[0020] And / or, the first metal discharge port is a siphon port.

[0021] In some embodiments, the reducing smelting zone comprises an electrothermal reduction section and a jet injection section, the molten slag flowing into the reducing smelting zone sequentially passes through the electrothermal reduction section and the jet injection section for reduction, and the second metal discharge port and the slag discharge port are arranged close to the jet injection section.

[0022] In some embodiments, further comprising an electrode arranged in the electrothermal reduction section, and a second lance, the reducing smelting zone further has a second feeding port for feeding a reducing agent into the electrothermal reduction section, and a second injection port arranged on the sidewall of the jet injection section, and the second lance is connected to the second injection port to feed carbonaceous reducing agent and oxygen into the jet injection section.

[0023] In some embodiments, the amount of oxygen injected into the jet injection section by the second lance is 0.1 to 0.5 of the total amount of oxygen required for complete combustion of the carbonaceous reducing agent.

[0024] In some embodiments, the electrothermal reduction section and the jet injection section are arranged along a first direction, and the length a of the electrothermal reduction section in the first direction and the length b of the jet injection section in the first direction satisfy: a>2b.

[0025] And / or, the heat supplement ratio of the electrothermal reduction section and the jet injection section is 2:1 to 5:1.

[0026] And / or, the CO to CO2 volume ratio in the reducing smelting zone is 20:1 to 35:1.

[0027] In some embodiments, the first processing unit comprises a dust collection device for recovering high-cadmium dust in the flue gas discharged from the oxidizing smelting zone.

[0028] In some embodiments, the second processing unit comprises a condensing device for condensing the flue gas discharged from the reducing smelting zone to recover crude zinc, and a rectifying device for refining crude zinc to separate valuable metals.

[0029] In some embodiments, the rectifying device has a first rectifying temperature of 900°C to 950°C to recover metallic lead in the crude zinc, and a second rectifying temperature of 500°C to 600°C to recover metallic cadmium in the crude zinc. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a structural schematic diagram of a zinc smelting and valuable metal recovery system according to an embodiment of the present application.

[0031] Figure 2 is a structural schematic diagram of a smelting device according to an embodiment of the present application.

[0032] Figure 3 is Figure 2 a structural schematic diagram of the A direction.

[0033] Reference signs:

[0034] 1, smelting device; 11, oxidation smelting zone; 111, first feeding port; 12, reduction smelting zone; 121, electric heating reduction section; 122, jet injection section; 123, second feeding port; 124, electrode; 13, first metal discharge port; 14, first smoke discharge port; 15, first injection port; 16, second metal discharge port; 17, slag discharge port; 18, second smoke discharge port; 19, second injection port;

[0035] 2, first processing unit;

[0036] 3, second processing unit; 31, condensing device; 32, rectifying device;

[0037] 41, reducing agent feeding device; 42, electrode lifting device; 43, mixing device; 44, feeding device;

[0038] 51, zinc concentrate; 52, flux. DETAILED DESCRIPTION

[0039] The embodiments of the present application will be described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0040] The following will be described in detail Figures 1-3 The zinc smelting and valuable metal recovery system and method according to the embodiments of the present application will be described in detail.

[0041] As Figures 1-3 shown, the zinc smelting and valuable metal recovery system according to the embodiments of the present application comprises a smelting device 1, the smelting device 1 has an oxidation smelting zone 11 and a reduction smelting zone 12, the bottom of the oxidation smelting zone 11 and the reduction smelting zone 12 is communicated, the zinc concentrate 51 is smelted and oxidized desulfurization in the oxidation smelting zone 11, the molten slag produced by the oxidation smelting zone 11 smelting flows into the reduction smelting zone 12 for reduction, the oxidation smelting zone 11 has a first smoke discharge port 14 and a first metal discharge port 13, the reduction smelting zone 12 has a second smoke discharge port 18, a second metal discharge port 16 and a slag discharge port 17.

[0042] The smelting device 1 provided by the embodiment of the utility model can realize short-process pyro metallurgy of zinc by oxidation desulfurization of the oxidation smelting area 11 and high-temperature reduction of the reduction smelting area 12, and the zinc concentrate 51 does not need complex preparation and processing, and the zinc concentrate 51, the flux 52 and oxygen are directly sent into the oxidation smelting area 11 to carry out oxidation desulfurization, avoiding processing the zinc concentrate 51 before entering the furnace. In the oxidation smelting area 11 in the embodiment of the utility model, the zinc concentrate 51 can be smelted to produce copper matte under the working condition of low temperature and low oxygen potential, and then most of the precious metals such as copper, gold and silver are captured, the copper matte is deposited at the bottom of the molten pool and discharged from the first metal discharge port 13, and then full desulfurization is carried out under the working condition of high temperature and high oxygen potential, producing smoke dust containing cadmium and lead, and the smoke dust is discharged from the first smoke discharge port 14 with the smoke. The slag of the oxidation smelting area 11 flows into the reduction smelting area 12, the slag contains zinc and the remaining valuable metals, the slag can be high-temperature reduced in the reduction smelting area 12, and produces pig iron water, and the remaining small amount of copper, gold, silver and other valuable metals are recovered in the pig iron water, the pig iron water is discharged from the second metal discharge port 16, and the remaining lead and cadmium and indium, germanium and other reduction formed steam are discharged from the second smoke discharge port 18 with zinc steam.

[0043] The pyro metallurgy zinc recovery valuable metal system further includes a first processing unit 2 and a second processing unit 3; the first processing unit 2 is connected with the first smoke discharge port 14, and the first processing unit 2 is used for recovering valuable metals in the smoke discharged from the oxidation smelting area 11, and the second processing unit 3 is connected with the second smoke discharge port 18, and the second processing unit 3 is used for recovering valuable metals in the smoke discharged from the reduction smelting area 12.

[0044] That is to say, the smoke and smoke dust generated by the oxidation smelting area 11 are discharged from the first smoke discharge port 14 and enter the first processing unit 2, realizing recovery of the smoke dust containing valuable metals cadmium and lead, and zinc steam carrying valuable metals is discharged from the second smoke discharge port 18 and enters the second processing unit 3, and then recovery of zinc and the remaining valuable metals is realized.

[0045] The pyro metallurgy zinc recovery valuable metal system of the embodiment of the utility model can realize short-process pyro metallurgy of zinc, and simplifies the preparation process and improves the metal recovery rate.

[0046] In some embodiments, the oxidation smelting area 11 has a first working condition and a second working condition.

[0047] Under the first working condition, the temperature in the oxidation smelting area is 1100 DEG C to 1300 DEG C, and the oxygen material ratio in the oxidation smelting area is 100 Nm 3 / t to 250 Nm 3 / t.

[0048] Under the second working condition, the temperature in the oxidation smelting area is 1350 DEG C to 1550 DEG C, and the oxygen material ratio in the oxidation smelting area is 300 Nm3 / t to 500 Nm 3 / t.

[0049] It should be understood that, in the first working condition, the low-temperature and low-oxygen potential condition is formed in the oxidation smelting zone, the zinc concentrate is oxidized and desulfurized under the low-temperature and low-oxygen potential condition in the oxidation smelting zone, and the high-sulfur and high-zinc slag and the copper matte which captures most of the precious metals such as copper, gold and silver are obtained, so that the recovery of most of the precious metals such as copper, gold and silver is realized. In the second working condition, the high-temperature and high-oxygen potential condition is formed in the oxidation smelting zone, and the high-zinc slag can be further desulfurized under the high-temperature and high-oxygen potential condition in the oxidation smelting zone to form the low-sulfur and high-zinc slag and the high-cadmium smoke containing cadmium and lead, so that the recovery of cadmium and lead is realized.

[0050] Under the low-temperature and low-oxygen potential condition, the high-sulfur and high-zinc slag formed contains S 2% to 5%, and the copper matte formed contains Cu 10% to 30%, and 70% to 80% of Cu, 80% to 90% of Au and 80% to 90% of Ag are enriched in the copper matte for recovery.

[0051] Under the high-temperature and high-oxygen potential condition, the low-sulfur and high-zinc slag formed contains S < 1%, and contains Zn 40% to 60%, and the high-cadmium smoke formed contains Cd > 12%.

[0052] The oxygen potential of the embodiment of the utility model is expressed by the oxygen material ratio, and the oxygen material ratio is the mass ratio of the oxygen gas volume to the ore material.

[0053] Further, in the first working condition, the temperature in the oxidation smelting zone is 1100 DEG C, 1130 DEG C, 1175 DEG C, 1200 DEG C, 1265 DEG C or 1300 DEG C, and the oxygen material ratio in the oxidation smelting zone is 100 Nm 3 / t, 120 Nm 3 / t, 142 Nm 3 / t, 155 Nm 3 / t, 195 Nm 3 / t, 230 Nm 3 / t or 250 Nm 3 / t.

[0054] In the second working condition, the temperature in the oxidation smelting zone is 1350 DEG C, 1380 DEG C, 1395 DEG C, 1426 DEG C, 1448 DEG C, 1496 DEG C, 1525 DEG C or 1550 DEG C, and the oxygen material ratio in the oxidation smelting zone is 300 Nm 3 / t, 320 Nm 3 / t, 342 Nm 3 / t, 355 Nm 3 / t, 395 Nm 3 / t, 430 Nm 3 / t, 495 Nm 3 / t or 500 Nm 3 / t.

[0055] By reasonably controlling the oxygen-material ratio in different stages, the stability of chemical reactions in different sections of the furnace can be ensured, the smelting process can be accurately controlled and optimized, the energy consumption and cost can be reduced, and the metal recovery rate can be improved.

[0056] In some embodiments, the pyrometallurgical zinc smelting valuable metal recovery system further comprises a first lance, the oxidation smelting zone 11 has a first nozzle 15, and the first lance is connected with the first nozzle 15 to spray oxygen into the oxidation smelting zone 11.

[0057] The first lance sprays oxygen or oxygen-enriched air into the oxidation smelting zone 11 to control the oxygen-material ratio in the oxidation smelting zone 11 and ensure the oxidation desulfurization treatment in different stages.

[0058] Optionally, the number of first lances is multiple, and the multiple first lances are arranged side by side and at intervals. The gas sprayed by the first lances can also fully stir the molten slag, so as to promote the chemical reactions in the oxidation smelting zone 11.

[0059] Further, the position of the first lance in the vertical direction is higher than the positions of the first metal discharge port 13 and the communication port between the oxidation smelting zone 11 and the reduction smelting zone 12, so as to avoid causing great disturbance to the copper matte deposited at the bottom of the oxidation smelting zone 11 and facilitate the smooth discharge of the copper matte.

[0060] In some embodiments, the oxidation smelting zone 11 further has a first feeding port 111 for feeding the zinc concentrate 51 and the flux 52 into the oxidation smelting zone 11. After the zinc concentrate 51 and the flux 52 are uniformly mixed by the mixing device 43, they are conveyed into the oxidation smelting zone 11 by a feeding machine device such as a conveyor, and the feeding is completed. The mixing device 43 can be a stirring drum, and the zinc concentrate 51 and the flux 52 can be mixed by stirring after being added to the stirring drum, which reduces the difficulty of material preparation and eliminates the need for other pre-furnace treatments.

[0061] The flux 52 can be quartz sand, and the ratio of the zinc concentrate 51 to the flux 52 is 5:1 to 20:1.

[0062] In some embodiments, the first metal discharge port 13 is a siphon port. Under the condition of low temperature and low oxygen potential, the copper matte formed in the oxidation smelting zone 11 is deposited at the bottom of the molten pool and discharged through the siphon port, which improves the quality of the copper matte, optimizes the smelting process, and avoids the molten slag from flowing out.

[0063] In some embodiments, the reduction smelting zone 12 comprises an electric heating reduction section 121 and a jet injection section 122, and the molten slag flowing into the reduction smelting zone 12 is sequentially subjected to reduction in the electric heating reduction section 121 and the jet injection section 122, and the second metal discharge port 16 and the slag discharge port 17 are arranged close to the jet injection section 122.

[0064] The embodiment of the utility model discloses the reduction of two stages of electric heating reduction section 121 and jet spray section 122, realize to the depth reduction of molten slag, the molten slag of flowing into reduction smelting area 12 from oxidizing smelting area 11 first passes through electric heating reduction section 121 reduction, then passes through jet spray section 122 depth reduction, and the residual small amount of copper, gold, silver and other valuable metals are discharged with pig iron water by second metal discharge port 16, and the slag is discharged by slag discharge port 17, and the residual lead and cadmium and indium, germanium and other valuable metals are discharged with high zinc vapor by second smoke outlet 18.

[0065] The embodiment of the utility model discloses the reduction of two stages of electric heating reduction section 121 and jet spray section 122, realize to the depth reduction of molten slag, the molten slag of flowing into reduction smelting area 12 from oxidizing smelting area 11 first passes through electric heating reduction section 121 reduction, then passes through jet spray section 122 depth reduction, and the residual small amount of copper, gold, silver and other valuable metals are discharged with pig iron water by second metal discharge port 16, and the slag is discharged by slag discharge port 17, and the residual lead and cadmium and indium, germanium and other valuable metals are discharged with high zinc vapor by second smoke outlet 18.

[0066] Further, the reduction smelting area 12 further includes an electrode 124 and a second lance, the electrode 124 is arranged in the electric heating reduction section 121, and the reduction smelting area 12 further has a second feeding port 123 and a second spray port 19; the second feeding port 123 is used for feeding a reducing agent into the electric heating reduction section 121; the reducing agent is quantitatively fed into the electric heating reduction section 121 through a reducing agent feeding device 41 connected with the second feeding port 123; and the second spray port 19 is arranged on a side wall of the jet spray section 122, and the second lance is connected with the second spray port 19 to feed carbonaceous reducing agent and oxygen into the jet spray section 122.

[0067] The electrode 124 is used for supplementing heat for the electric heating reduction section 121, the reducing agent is added into the electric heating reduction section 121 through the second feeding port 123, and the second lance is used for feeding the carbonaceous reducing agent and the oxygen into the jet spray section 122, so that heat can be provided for the depth reduction, and the reducing agent can be provided for the reduction process.

[0068] In the embodiment of the utility model, the amount of oxygen sprayed into the jet spray section 122 through the second lance is 0.1 to 0.5 of the total amount of oxygen required for complete combustion of the carbonaceous reducing agent, so that the carbonaceous reducing agent is partially combusted to supplement heat, and the uncombusted part can be used as the reducing agent to perform high-temperature depth reduction treatment on the molten slag, thereby improving the efficiency and effect of smelting.

[0069] The electrode 124 is a graphite electrode 124, and an electrode lifting device 42 is further arranged to drive the electrode 124 to ascend and descend along the vertical direction.

[0070] Optionally, the amount of oxygen injected into the jet injection section 122 by the second lance is 0.1, 0.2, 0.33, 0.36, 0.41, 0.44, 0.485, or 0.5 times the total amount of oxygen required for complete combustion of the carbonaceous reducing agent. When the amount of oxygen injected into the jet injection section 122 by the second lance is too small, i.e., less than 0.1 times the total amount of oxygen required for complete combustion of the carbonaceous reducing agent, it is difficult to achieve the desired heat supplement effect, and the jet injection section 122 cannot achieve the effect of deep reduction. When the amount of oxygen injected into the jet injection section 122 by the second lance is too large, i.e., more than 0.5 times the total amount of oxygen required for complete combustion of the carbonaceous reducing agent, it will result in waste of heat, increase in heat consumption, and reduction in the amount of reducing agent, which is not conducive to deep reduction.

[0071] Further, the heat supplement ratio of the electrothermal reduction section 121 and the jet injection section 122 is 2:1 to 5:1, for example, the heat supplement ratio of the electrothermal reduction section 121 and the jet injection section 122 is 2:1, 3:1, 3.4:1, 4.2:1, 4.6:1, or 5:1. By adjusting the heat supplement ratio of the electrothermal reduction section 121 and the jet injection section 122, the temperature and the degree of reduction treatment of the molten slag in the electrothermal reduction section 121 and the jet injection section 122 can be optimized, the reduction process can be optimized, and the smelting effect can be improved.

[0072] Further, the CO to CO2 volume ratio in the reduction smelting area 12 is 20:1 to 35:1. Controlling the CO to CO2 volume ratio in the reduction smelting area 12 within a reasonable range optimizes the reduction treatment process, ensures production efficiency, and improves product quality, which helps to improve the direct yield and recovery rate of the metal.

[0073] In some embodiments, the electrothermal reduction section 121 and the jet injection section 122 are arranged along a first direction, and the length a of the electrothermal reduction section 121 in the first direction and the length b of the jet injection section 122 in the first direction satisfy: a>2b.

[0074] In the embodiments of the utility model, the space of the reduction smelting area 12 is further optimized, the reduction treatment effect of the molten slag in the area can be improved, the molten slag can be fully and deeply reduced, and high-quality products can be obtained.

[0075] The cross section of the reduction smelting area 12 is approximately rectangular, and the first direction is the length direction of the cross section of the reduction smelting area 12.

[0076] For example, the length of the reduction smelting area 12 in the first direction is L, the length a of the electrothermal reduction section 121 in the first direction is 3 / 4L, and the length b of the jet injection section 122 in the first direction is 1 / 4L.

[0077] Alternatively, the length a of the electrothermal reduction section 121 in the first direction is 5 / 7L, and the length b of the jet injection section 122 in the first direction is 2 / 7L.

[0078] When a≤2b, the reduction treatment effect of the slag in the reduction smelting zone 12 is poor, the reduction treatment time of the slag in the electrothermal reduction section 121 is relatively short, and the reduction treatment time of the slag in the jet injection section 122 is relatively long, which affects the smelting effect of the slag and the quality of the product.

[0079] In some embodiments, the first treatment unit 2 includes a dust collection device for recovering high-cadmium smoke dust in the flue gas discharged from the oxidation smelting zone 11.

[0080] After the high-cadmium smoke dust and the flue gas pass through the dust collection device, the high-cadmium smoke dust and the flue gas containing sulfides are separated, the flue gas is discharged to the atmosphere after harmless treatment, and the valuable metals such as cadmium and lead in the high-cadmium smoke dust are recovered.

[0081] Further, the second treatment unit 3 includes a condensing device 31 and a rectifying device 32, the condensing device 31 is used for condensing the flue gas discharged from the reduction smelting zone 12 to recover crude zinc, and the rectifying device 32 is used for refining the crude zinc to separate valuable metals.

[0082] The high-zinc vapor produces crude zinc after passing through the condensing device 31, and the crude zinc is refined by the rectifying device 32, and then zinc, lead and cadmium are obtained.

[0083] The rectifying device 32 has a first rectifying temperature and a second rectifying temperature, the first rectifying temperature is 900-950 DEG C. to recover the metal lead in the crude zinc, and the second rectifying temperature is 500-600 DEG C. to recover the metal cadmium in the crude zinc.

[0084] The valuable metals such as cadmium, lead, indium and germanium can be recovered by rectification, the metal lead in the crude zinc is recovered at the first rectifying temperature, and the metal cadmium in the crude zinc is recovered at the second rectifying temperature.

[0085] For example, the first rectifying temperature is 900 DEG C., 910 DEG C., 915 DEG C., 923 DEG C., 936 DEG C., 947 DEG C. or 950 DEG C. The second rectifying temperature is 500 DEG C., 510 DEG C., 517 DEG C., 522 DEG C., 536 DEG C., 539 DEG C. or 500 DEG C. By reasonably controlling the rectifying temperature at different stages, refined zinc and other valuable metals are obtained.

[0086] The refined zinc in the embodiment of the utility model has Zn>99.995%.

[0087] Meanwhile, the recovery rates of zinc, lead, copper, cadmium, gold, silver, indium, and germanium in this embodiment of the invention can reach 97% to 98%, 97% to 98%, 90% to 95%, 90% to 95%, 90% to 95%, 90% to 95%, 90% to 95%, 90% to 95%, 90% to 95%, and 90% to 95%, respectively.

[0088] The above-mentioned pyrometallurgical zinc smelting and valuable metal recovery system includes the following steps:

[0089] S101. Zinc concentrate 51, flux 52, and oxygen are fed into the oxidation smelting zone 11 for melting and oxidation desulfurization treatment, yielding copper matte and sulfur-containing slag. The copper matte is discharged through the first metal discharge port 13. The copper matte contains 10% to 30% Cu, and 70% to 80% Cu, 80% to 90% Au, and 80% to 90% Ag are enriched in the copper matte and can be recovered. The sulfur-containing slag contains 2% to 5% S.

[0090] In this step, oxidation desulfurization is carried out under low temperature and low oxygen potential conditions, that is, the reaction is carried out under the first working condition in the above embodiment.

[0091] S102. Increase the temperature and oxygen-to-material ratio in the oxidation smelting zone 11, further oxidize and desulfurize the sulfur-containing slag in the oxidation smelting zone 11, and obtain high-cadmium dust and low-sulfur slag. The low-sulfur slag flows into the reduction smelting zone 12, and the high-cadmium dust is discharged through the first exhaust port 14 and collected through the first processing unit 2.

[0092] Among them, high-cadmium flue dust contains Cd > 12%, low-sulfur slag contains S < 1%, and Zn 40% to 60%.

[0093] In this step, high temperature and high oxygen potential conditions are used for further desulfurization, that is, the reaction is carried out under the second working condition in the above embodiment.

[0094] In this embodiment of the invention, the crude zinc is refined by a crude zinc distillation apparatus 32. In the distillation apparatus 32, cadmium and lead are separated and recovered by controlling the temperature.

[0095] In this embodiment of the invention, the raw materials are highly adaptable, requiring no complex preparation; the materials can be directly fed into the furnace after mixing. The mixed materials undergo oxidation and desulfurization in the oxidation smelting zone 11 under low temperature and low oxygen potential conditions to form copper matte, capturing valuable metals such as copper, gold, and silver. Then, the temperature and oxygen potential of the oxidation smelting zone 11 are increased to achieve deep desulfurization and form high-cadmium flue dust to recover valuable metals such as cadmium and lead.

[0096] S103, adding a reducing agent to the reduction smelting area 12 to reduce the low-sulfur slag, obtaining valuable metal zinc vapor and molten iron, the zinc vapor is discharged from the second smoke outlet 18 and refined and separated from the valuable metal by the second processing unit 3, and the molten iron is discharged from the second metal discharge port 16.

[0097] The high-zinc slag (i.e. low-sulfur slag) is reduced in the reduction smelting area 12, by controlling the CO / CO2 volume ratio, the valuable metals in the reduction smelting area 12, the zinc in the slag is reduced to form zinc vapor, the valuable metals such as cadmium, lead, indium and germanium are volatilized into the zinc vapor, and the zinc vapor is discharged from the second smoke outlet 18 of the reduction smelting area 12, and the zinc vapor is condensed by the condensing device 31 to produce crude zinc; the iron in the high-zinc slag is reduced to generate pig iron, and the valuable metals such as copper, gold and silver are enriched in the pig iron and recovered.

[0098] In the reduction process of the embodiment of the utility model, by controlling the CO / CO2 volume ratio, pig iron is generated, and the valuable metals such as copper, gold and silver are collected and recovered, at the same time, the valuable metals such as cadmium, lead, indium and germanium are enriched in the zinc vapor, crude zinc is obtained by condensing the zinc vapor, and the crude zinc is rectified, the remaining lead and cadmium are recovered, and the high-boiling-point metals such as indium and germanium are enriched in the hard zinc and further recovered.

[0099] The system of the embodiment of the utility model, the recovery rate of zinc can reach 97% to 98%, the recovery rate of lead can reach 97% to 98%, the recovery rate of copper can reach 90% to 95%, the recovery rate of cadmium can reach 90% to 95%, the recovery rate of gold can reach 90% to 95%, the recovery rate of silver can reach 90% to 95%, the recovery rate of indium can reach 90% to 95%, and the recovery rate of germanium can reach 90% to 95%.

[0100] In the description of the utility model, it is understood that the terms "first", "second" are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the utility model, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0101] In the utility model, unless otherwise specifically defined and limited, the terms "installation", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected or in communication with each other; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For ordinary skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0102] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature is "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or it only means that the horizontal height of the first feature is higher than that of the second feature. The first feature is "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or it only means that the horizontal height of the first feature is less than that of the second feature.

[0103] In the present application, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0104] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. Those skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A pyrometallurgical zinc smelting recovery of value metals system, characterized in that, The system comprises a smelting device; The smelting device has an oxidizing smelting zone and a reducing smelting zone, the bottom of the oxidizing smelting zone and the reducing smelting zone are communicated, zinc concentrate is smelted and oxidized desulfurization in the oxidizing smelting zone, the smelting slag generated in the oxidizing smelting zone flows into the reducing smelting zone for reduction; The oxidizing smelting zone has a first smoke outlet and a first metal discharge port, the reducing smelting zone has a second smoke outlet, a second metal discharge port and a slag discharge port; The pyrometallurgical zinc smelting and valuable metal recovery system further comprises: A first processing unit and a second processing unit; The first processing unit is connected with the first smoke outlet, the first processing unit is used for recovering valuable metals in the flue gas discharged from the oxidizing smelting zone, the second processing unit is connected with the second smoke outlet, and the second processing unit is used for recovering valuable metals in the flue gas discharged from the reducing smelting zone.

2. The zinc fire assay value metal recovery system of claim 1, wherein, The oxidizing smelting zone has a first working condition and a second working condition; In the first working condition, the temperature in the oxidizing smelting zone is 1100°C to 1300°C, the oxygen material ratio in the oxidizing smelting zone is 100 Nm 3 / t to 250 Nm 3 / t; In the second working condition, the temperature in the oxidizing smelting zone is 1350°C to 1550°C, the oxygen material ratio in the oxidizing smelting zone is 300 Nm 3 / t to 500 Nm 3 / t.

3. The pyrometallurgical zinc refining and value metal recovery system of claim 1, wherein, Further comprising a first lance, the oxidizing smelting zone has a first nozzle, the first lance is connected with the first nozzle to inject oxygen into the oxidizing smelting zone; And / or, the oxidizing smelting zone further has a first feeding port, the first feeding port is used for feeding zinc concentrate and flux into the oxidizing smelting zone; And / or, the first metal discharge port is a siphon port.

4. The zinc fire assay value metal recovery system of claim 1, wherein, The reducing smelting zone comprises an electric heating reduction section and a jet injection section, the smelting slag flowing into the reducing smelting zone sequentially passes through the electric heating reduction section and the jet injection section for reduction, and the second metal discharge port and the slag discharge port are arranged close to the jet injection section.

5. The pyrometallurgical zinc refining and value metal recovery system according to claim 4, characterized in that, Further comprising an electrode and a second lance, the electrode is arranged in the electric heating reduction section, the reducing smelting zone further has a second feeding port and a second nozzle, the second feeding port is used for feeding a reducing agent into the electric heating reduction section, the second nozzle is arranged on the side wall of the jet injection section, and the second lance is connected with the second nozzle to feed carbonaceous reducing agent and oxygen into the jet injection section.

6. The zinc fire assay value metal recovery system of claim 5, wherein, The amount of oxygen injected into the jet injection section by the second lance is 0.1 to 0.5 of the total amount of oxygen required for complete combustion of the carbonaceous reducing agent.

7. A zinc fire assay value metal recovery system according to claim 5 or 6, characterised in that, The electric heating reduction section and the jet injection section are arranged along a first direction, the length a of the electric heating reduction section in the first direction and the length b of the jet injection section in the first direction satisfy: a>2b; And / or, the heat supplement ratio of the electric heating reduction section and the jet injection section is 2:1 to 5:1; And / or, the CO to CO2 volume ratio in the reducing smelting zone is 20:1 to 35:

1.

8. The zinc fire assay value metal recovery system of claim 1, wherein, The first processing unit comprises a dust collection device, and the dust collection device is used for recovering high-cadmium dust in the flue gas discharged from the oxidizing smelting zone.

9. The pyrometallurgical zinc-recovery value-metal system of claim 1, wherein, The second processing unit comprises a condensing device and a rectifying device, the condensing device is used for condensing the flue gas discharged from the reducing smelting zone to recover crude zinc, and the rectifying device is used for refining the crude zinc to separate valuable metals.

10. The zinc fire assay value metal recovery system of claim 9, wherein, The rectification device has a first rectification temperature of 900 to 950°C to recover metallic lead in the crude zinc and a second rectification temperature of 500 to 600°C to recover metallic cadmium in the crude zinc.

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