Purified cobalt slag recycling system
By linking the copper-cadmium slag with the purified cobalt slag treatment process, using the elemental zinc powder in the purified cobalt slag to replace the cobalt ion replacement in the cadmium-deficient liquid, the problem of high treatment cost in wet zinc smelting is solved, and the consumption of zinc powder and the economic benefits are reduced.
Patent Information
- Application Number
- CN202422058018.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-08-23
AI Technical Summary
In the three-stage purification process of wet zinc smelting, the separate treatment of copper cadmium slag and purified cobalt slag leads to high processing costs and low economic benefits, and cuts off the mutual promotion effect between the two.
The copper-cadmium slag treatment process is linked to the purified cobalt slag treatment process, and the residual elemental zinc powder in the purified cobalt slag is used to replace the replacement operation of cobalt ions in the cadmium-depleted liquid, thereby reducing the consumption of zinc powder.
It effectively reduces the consumption of zinc powder in the cobalt removal operation of cadmium-leaving liquid, controls the cobalt content in the cadmium-leaving liquid after cobalt removal, simplifies the processing system settings, reduces production costs, and improves the recovery rate.
Smart Images
Figure CN223016929U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of hydrometallurgical zinc smelting, and particularly relates to a purification cobalt slag recycling system. Background Art
[0002] In the three-stage purification process of hydrometallurgical zinc smelting, two kinds of slags, namely copper-cadmium slag and purification cobalt slag, will be produced in the first and second stage purification processes respectively. At present, these two kinds of slags are generally treated separately. As Figure 2 shown, after the copper-cadmium slag is leached and copper and cadmium are separated by replacement, the cadmium-poor liquid is de-cobalted and then returned to the main system. The de-cobalt process mainly uses zinc powder to replace cobalt ions in the cadmium-poor liquid, which consumes a large amount of zinc powder; the second-stage purification cobalt slag is directly filtered after being slurried and pickled. The high-cobalt slag is transported to the cobalt recovery system for further purification, and the cadmium-poor liquid needs to be collected and stored, increasing the storage facilities. Treating the two kinds of slags separately like this can reduce the interference between various metal elements, but it also cuts off the mutual promotion effect between them, resulting in increased treatment costs and reduced economic benefits. Summary of the Utility Model
[0003] Aiming at the existing problems, the utility model provides a purification cobalt slag recycling system, which connects the copper-cadmium slag treatment process with the purification cobalt slag treatment process, and makes full use of the residual elemental zinc powder in the purification cobalt slag to replace cobalt ions in the cadmium-poor liquid, thereby reducing the consumption of zinc powder in the cobalt precipitation operation of the cadmium-poor liquid and reducing the treatment cost.
[0004] The specific technical solution of the utility model is: a purification cobalt slag recycling system, including a waste liquid storage tank and a first-stage purification system, a second-stage purification system and a third-stage purification system connected to it in sequence. The first-stage purification system, the second-stage purification system and the third-stage purification system all include a purification tank, an intermediate tank and a filter press. The slag outlet of the filter press of the first-stage purification system is connected to the copper-cadmium slag slurrying tank, and the copper-cadmium slag slurrying tank is sequentially connected to the copper-cadmium slag leaching tank, a first-stage replacement system and a second-stage replacement system. Both the first-stage replacement system and the second-stage replacement system include a replacement tank and a filter press; the liquid outlet of the filter press of the second-stage replacement system is connected to the inlet of the cobalt slag slurrying tank, and the outlet of the cobalt slag slurrying tank is sequentially connected to the cobalt slag pickling tank and the cobalt slag filter press. The slag outlet of the cobalt slag filter press is connected to the cobalt recovery system. The slag outlets of the filter presses of the second-stage purification system and the third-stage purification system are connected to the cobalt slag slurrying tank, and the liquid outlets of the filter press of the third-stage purification system and the cobalt slag filter press are connected to the replacement tank of the second-stage replacement system.
[0005] Further, preferably, the bottom flow port of the waste liquid storage tank is connected to the purification tank of the second-stage purification system.
[0006] The beneficial effects of the present utility model are as follows: The present utility model fully considers the relevance between the copper-cadmium slag treatment process and the purified cobalt slag treatment process, directly mixes the cadmium-depleted liquid generated by the copper-cadmium slag treatment system with the cobalt slag generated by the second-stage and third-stage purification systems, makes full use of the residual elemental zinc powder in the cobalt slag, replaces part of the zinc powder required for the cobalt precipitation operation in the cadmium-depleted liquid, displaces the cobalt in the cadmium-depleted liquid, effectively reduces the consumption of zinc powder for cobalt removal from the cadmium-depleted liquid, controls the process index that the cobalt content in the cadmium-depleted liquid after cobalt removal is lower than 0.03 g / L, and simplifies the overall settings of the copper-cadmium slag treatment system and the cobalt slag treatment system, further reducing the production cost.
[0007] It has a promoting effect on both economic benefits and technical benefits. In addition, the present utility model also realizes the cadmium-cobalt recycling of the cadmium-depleted liquid generated by the cobalt slag treatment system and the third-stage purification system, which is beneficial to improving the recovery rate. BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Figure 1 It is an equipment connection diagram of a purified cobalt slag recycling and utilization system of the present utility model;
[0009] Figure 2 It is an equipment connection diagram of an existing purified cobalt slag recycling and utilization system;
[0010] In the figure: 1 - waste liquid storage tank, 2 - first-stage purification system, 3 - second-stage purification system, 4 - third-stage purification system, 5 - copper-cadmium slag slurrying tank, 6 - copper-cadmium slag leaching tank, 7 - first-stage replacement system, 8 - second-stage replacement system, 9 - cadmium-depleted liquid cobalt precipitation tank, 10 - cobalt slag slurrying tank, 11 - cobalt slag pickling tank, 12 - cobalt slag filter press, 13 - cobalt recovery system, 14 - cadmium-depleted liquid storage tank. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0011] In order to make the technical problems and technical solutions solved by the present utility model clearer, the following further details the present utility model in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.
[0012] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.
[0013] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0014] Principle of the three-stage purification process:
[0015] In the purification and cobalt removal process of hydrometallurgical zinc smelting, a large amount of zinc-cobalt slag will be generated, which contains rich metal elements such as zinc, cadmium, copper, and cobalt. Based on the different standard electrode potentials of metals, the zinc powder replacement method is adopted. First, at low temperature, metallic zinc reacts with copper and cadmium ions to generate copper-cadmium slag precipitate, which is removed from the solution; then, at high temperature, an antimony salt is added as a catalyst, and metallic zinc reacts with cobalt and nickel ions to generate cobalt slag (containing nickel) precipitate, which is removed from the solution. The specific reaction equations are as follows:
[0016] CuSO4 + Zn → ZnSO4 + Cu (1)
[0017] CdSO4 + Zn → ZnSO4 + Cd (2)
[0018] CoSO4 + Zn → ZnSO4 + Co (3)
[0019] NiSO4 + Zn → ZnSO4 + Ni (4)
[0020] Leaching principle of copper-cadmium slag:
[0021] The copper-cadmium slag is leached with dilute sulfuric acid or waste electrolyte. Metallic zinc, cadmium, and their oxides are all dissolved in the dilute acid; while metallic copper is insoluble in the dilute acid and enters the leaching residue, thus achieving the separation of copper from cadmium and zinc. The cadmium-rich solution obtained by leaching is then replaced with zinc powder to obtain sponge cadmium.
[0022] Principle of cobalt precipitation from cadmium-poor solution:
[0023] The leaching filtrate of copper-cadmium residue - the cobalt-deficient solution contains some cobalt elements and needs to be treated for cobalt precipitation. For the traditional separate treatment of copper-cadmium residue, a large amount of zinc powder needs to be added separately (generally, the cobalt mass concentration in the cobalt-deficient solution is 0.1 - 0.2 g / L, and 1.0 - 1.5 t of zinc powder needs to be consumed every day). Considering that for the high-temperature cobalt and nickel removal in the second-stage purification system 3, about 200 - 250 times the amount of cobalt and nickel metals of zinc powder needs to be added to make the cobalt and nickel removal reach the standard. During this reaction process, there is a large amount of unreacted zinc powder. The zinc mass fraction in the cobalt slag is as high as about 55%, and most of the zinc is elemental zinc, which has high utilization value. Therefore, in this application, the cobalt-deficient solution is directly added to the cobalt slag slurry tank to be mixed with the cobalt slag, and the residual elemental zinc powder in the cobalt slag in the second and third stages of purification is used to replace part of the zinc powder required for the cobalt precipitation operation of the cobalt-deficient solution, so as to displace the cobalt in the cobalt-deficient solution, make the cobalt element in the cobalt-deficient solution enter the subsequent cobalt recovery system for recovery, and can also control the cobalt content in the cobalt-deficient solution after cobalt precipitation to be lower than the process index of 0.03 g / L.
[0024] Principle of pickling cobalt slag for purification:
[0025] The cobalt slag in the second and third stages of purification is pickled with dilute sulfuric acid or electrolytic waste liquid under heating conditions to dissolve part of the excessive zinc powder therein, and then zinc powder and potassium antimony tartrate are added to precipitate part of the dissolved cobalt element, so that as much cobalt element as possible enters the subsequent cobalt recovery system for recovery.
[0026] Based on the above principle, as Figure 1 shown, the present utility model provides a cobalt slag recovery and utilization system for purification, which includes a waste liquid storage tank 1 and a first-stage purification system 2, a second-stage purification system 3 and a third-stage purification system 4 connected to it in sequence. The first-stage purification system 2, the second-stage purification system 3 and the third-stage purification system 4 all include a purification tank, an intermediate tank and a filter press, and the purification tank, the intermediate tank and the filter press are connected in sequence. This part is the conventional setting of the three-stage purification process. The underflow port of the waste liquid storage tank 1 is connected to the purification tank of the second-stage purification system 3, and the precipitated bottom liquid directly enters the second-stage purification system 3 for treatment.
[0027] The slag outlet of the filter press of the first-stage purification system 2 is connected to the copper-cadmium slag slurry tank 5. The cadmium-copper slurry tank 5 is connected to the copper-cadmium slag leaching tank 6, the first-stage replacement system 7 and the second-stage replacement system 8 in sequence. The first-stage replacement system 7 and the second-stage replacement system 8 both include a replacement tank and a filter press. The copper-cadmium slag slurry tank 5, the copper-cadmium slag leaching tank 6, the first-stage replacement system 7 and the second-stage replacement system 8 together constitute a copper-cadmium slag treatment system, which simplifies the setting of the cobalt precipitation tank 9 for cobalt-deficient solution compared with the existing copper-cadmium slag treatment system.
[0028] The outlet of the filter press of the secondary replacement system 8 is connected to the inlet of the cobalt slag slurrying tank 10. The outlet of the cobalt slag slurrying tank 10 is successively connected to a cobalt slag pickling tank 11 and a cobalt slag filter press 12. The slag outlet of the cobalt slag filter press 12 is connected to a cobalt recovery system 13. The filter press slag outlets of the secondary purification system 3 and the tertiary purification system 4 are connected to the cobalt slag slurrying tank 10. The filter press outlets of the filter press of the tertiary purification system 4 and the cobalt slag filter press 12 are connected to the replacement tank of the secondary replacement system 8. The cobalt slag slurrying tank 10, the cobalt slag pickling tank 11, the cobalt slag filter press 12 and the cobalt recovery system 13 together constitute a cobalt slag treatment system, which simplifies the setting of the cadmium-poor liquid storage tank 14 compared with the existing cobalt slag treatment system.
[0029] Working principle: The waste liquid in the hydrometallurgical zinc process is stored in the waste liquid storage tank 1. The supernatant of the waste liquid storage tank 1 is directly transported to the purification tank 1# of the primary purification system 2. Zinc powder is added to cause a replacement reaction between metallic zinc and copper and cadmium ions to generate copper-cadmium slag precipitates. Then, it is filtered by the filter press 1#. The copper-cadmium slag precipitates are transported to the copper-cadmium slurrying tank 5 and the leaching tank 6 for reaction. The cadmium-rich liquid continues to the replacement tank 1# of the primary replacement system 7. Zinc powder is added for reaction to generate sponge cadmium precipitates. The cadmium-poor liquid separated by filtering through the filter press 4# continues to the replacement tank 2# of the secondary replacement system 8. Zinc powder is added for a secondary reaction to generate sponge cadmium precipitates, and the sponge cadmium is separated by filtering through the filter press 5#.
[0030] The bottom liquid of the waste liquid storage tank 1 and the filtrate filtered out by the primary purification system 1 are transported to the purification tank 2# of the secondary purification system 3. Using the method of zinc powder replacement and antimony salt catalysis, zinc powder and antimony salt are added to cause a replacement reaction between metallic zinc and cobalt and nickel ions to generate cobalt slag (containing nickel) precipitates. After filtering by the filter press 2#, the filtrate continues to the purification tank 3# of the tertiary purification system 4. Zinc powder is added to cause a secondary replacement reaction between metallic zinc and cobalt and nickel ions to generate cobalt slag (containing nickel) precipitates. The cobalt slag filtered out by the filter press 2# and the filter press 3# are all transported to the cobalt slag slurrying tank 10. The filtrate filtered out by the filter press 3# returns to the replacement tank 2# of the secondary replacement system 8 to recycle cadmium and cobalt repeatedly.
[0031] The remaining cadmium-poor liquid filtered out by the filter press 5# is sent to the cobalt slag slurrying tank 10 to slurry the cadmium-poor liquid with the cobalt slag mixture from the secondary and tertiary purification. The residual metallic zinc powder in the cobalt slag plays a role in replacing the cobalt in the cadmium-poor liquid.
[0032] Then it continues to the cobalt slag pickling tank 11 for pickling to dissolve some of the excessive zinc powder and precipitate some dissolved cobalt elements. The cobalt elements are filtered out by the cobalt slag filter press 12 and enter the subsequent cobalt recovery system 13 for recovery. The filtrate filtered out by the cobalt slag filter press 12 returns to the replacement tank 2# of the secondary replacement system 8 to recycle cadmium and cobalt repeatedly.
[0033] The present utility model has been described in detail through specific and preferred embodiments. However, those skilled in the art should understand that the present utility model is not limited to the above-described embodiments. Any modifications, equivalent substitutions, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.
Claims
1. A system for recycling and purifying cobalt slag, comprising a waste liquid storage tank (1) and a first-stage purification system (2), a second-stage purification system (3) and a third-stage purification system (4) connected thereto in sequence, wherein the first-stage purification system (2), the second-stage purification system (3) and the third-stage purification system (4) all comprise a purification tank, an intermediate tank and a filter press, and characterized in that: The slag outlet of the filter press of the first-stage purification system (2) is connected to the copper-cadmium slag slurry tank (5), the copper-cadmium slag slurry tank (5) is connected in sequence to the copper-cadmium slag leaching tank (6), the first-stage replacement system (7) and the second-stage replacement system (8), the first-stage replacement system (7) and the second-stage replacement system (8) both comprising a replacement tank and a filter press; the liquid outlet of the filter press of the second-stage replacement system (8) is connected to the inlet of the cobalt slag slurry tank (10), the outlet of the cobalt slag slurry tank (10) is connected in sequence to the cobalt slag pickling tank (11) and the cobalt slag filter press (12), the slag outlet of the cobalt slag filter press (12) is connected to the cobalt recovery system (13), the slag outlets of the filter presses of the second-stage purification system (3) and the third-stage purification system (4) are connected to the cobalt slag slurry tank (10), the liquid outlets of the filter press of the third-stage purification system (4) and the cobalt slag filter press (12) are connected to the replacement tank of the second-stage replacement system (8).
2. A system for recycling purified cobalt slag according to claim 1, characterized in that: The bottom flow outlet of the waste liquid storage tank (1) is connected to the purification tank of the second-stage purification system (3).