Processing technology for recovering iron metal and copper metal from smelting copper slag tailings

Abstract

The invention discloses a processing technology for recovering iron metal and copper metal from smelting copper slag tailings, and particularly discloses a new technological process which comprises the following steps: firstly, enriching the copper metal in iron ore through a preliminary sorting section, namely, the iron metal and the copper metal are associated; copper-containing minerals and iron ore concentrates can be effectively separated out through magnetic separation; in the whole process, the recovery efficiency of the copper metal is remarkably improved, the common copper loss phenomenon in the traditional process is reduced, the copper is extracted while the iron metal is recovered from the smelting slag tailings, efficient utilization of resources can be achieved, the environmental burden can be reduced, and sustainable development can be promoted.

Description

Technical Field

[0001] The present invention relates to the field of non-ferrous metallurgy, and particularly to a processing technology for recovering iron metal and copper metal from smelted copper slag tailings. Background Art

[0002] Copper smelting slag is called "artificial copper ore", and its formation process mainly originates from the waste slag generated during pyrometallurgical copper smelting. Under the condition of high-temperature oxidation, copper concentrate undergoes a series of complex physical and chemical reactions, enabling copper elements to be enriched in copper matte. At the same time, the associated iron oxides, gangue and other impurities also aggregate, thus finally forming copper slag. In the composition of copper slag, the main components are iron oxide and silicon dioxide, and in addition, there are also small amounts of calcium oxide, aluminum oxide and magnesium oxide. In its crystal phase, fayalite is the main component, and in addition, there are also small amounts of magnetite and quartz. The existence of these components makes copper slag a resource containing various recoverable valuable metals.

[0003] During the smelting process, due to different smelting conditions, such as the type of additive, cooling time and smelting method, etc., the obtained copper slag will show significant differences in physical and chemical properties. These differences not only affect the composition of copper slag, but also directly relate to the subsequent treatment methods. Therefore, for different types of copper slag, corresponding recovery and treatment strategies need to be adopted.

[0004] The iron element in copper slag mainly exists in the form of fayalite and magnetic iron oxide. According to relevant data, the iron grade in copper slag is usually about 40%, which is significantly higher than the average industrial grade of iron ore in China (29.1%). Therefore, as a resource rich in iron, the recovery and utilization of copper slag has important economic value. At present, the recovery of iron element in copper slag mainly adopts technologies such as magnetic separation method and leaching method, etc., and these methods can effectively separate and extract the iron resources therein, so as to realize the reuse of resources and environmental protection.

[0005] When recovering iron metal from smelted slag tailings, an interesting phenomenon is found: during the enrichment process of iron metal, some copper elements will also be further enriched. This phenomenon not only affects the composition of the tailings, increasing its copper content, but also brings challenges to the subsequent copper recovery process.

[0006] Therefore, a processing technology for recovering iron metal and copper metal from smelted copper slag tailings is proposed to solve the above problems of simultaneously recovering iron metal and copper metal. Summary of the Invention

[0007] In order to solve the above problems existing in the prior art, the present invention provides a processing technology for recovering iron metal and copper metal from smelted copper slag tailings.

[0008] The technical solution of the present invention is as follows:

[0009] A processing technology for recovering iron metal and copper metal from smelting copper slag tailings, comprising the following steps:

[0010] S1. Input the flotation tailings slurry into a primary cylindrical magnetic separator through a tailings transfer pump for preliminary magnetic separation to separate magnetic tailings and magnetic concentrates;

[0011] S2. The magnetic tailings flow into the tailings tank by gravity, and the magnetic concentrates flow into a tower mill for regrinding;

[0012] S3. The discharge of the tower mill goes to the tower mill discharge pump sump, and then is pumped into a hydrocyclone by a discharge pump for classification. The underflow of the hydrocyclone returns to the tower mill for circulating grinding, and the overflow of the hydrocyclone enters a flotation cell for flotation operation;

[0013] S4. The foam slurry generated in the flotation cell enters the concentrate tank, and then is sent to the flotation cell by a concentrate pump for further separation. Then, the flotation underflow slurry in the flotation cell is input into the flotation underflow pump sump, and after the flotation cell underflow enters the flotation underflow pump sump, it is sent into a secondary cylindrical magnetic separator by a flotation discharge pump for further magnetic separation; meanwhile, a part of the non-flotation underflow slurry in the flotation cell is sent into the middling flotation pump sump;

[0014] S5. The magnetic tailings separated by the secondary cylindrical magnetic separator in step S4 above flow into the tailings tank by gravity, and the magnetic concentrates are pumped into a permanent magnet elutriation concentrator. The iron concentrate slurry separated by the permanent magnet elutriation concentrator enters the iron concentrate pump sump; then the tailings flow into the tailings tank by gravity and are sequentially filtered and dewatered to obtain tailings;

[0015] S6. The iron concentrate slurry in the iron concentrate pump sump in step S5 above is pumped to an iron concentrate ceramic filter, and iron concentrate is obtained after filtration and dewatering;

[0016] S7. The slurry entering the middling flotation cell in step S4 above is sent into the next flotation cell by a middling flotation pump for flotation, and then is sequentially filtered and dewatered to obtain copper concentrate.

[0017] Preferably, the feeding methods of the tower mill in step S2 include two optional modes: direct gravity feeding and feeding through a pump sump for transfer pumping.

[0018] Preferably, the pressure control range for the hydrocyclone classification operation in step S3 is 0.15 - 0.22 MPa, and the classification particle size is that -0.074 mm accounts for 60% - 85%.

[0019] Preferably, the magnetic field intensity of the permanent magnet elutriation concentrator in step S5 is 800 Gs, and the number of concentration times is 2 - 3 times.

[0020] Preferably, both the primary cylindrical magnetic separator in step S1 and the secondary cylindrical magnetic separator in step S4 adopt a semi-countercurrent trough structure.

[0021] Preferably, the filter medium of the ceramic filter press in step S6 is an alumina ceramic filter plate, and the porosity of the alumina ceramic filter plate is 30%-45%.

[0022] The present invention has the following beneficial effects: The present invention proposes a new process flow. First, the copper metal in iron ore is enriched through preliminary separation means, that is, iron metal is associated with copper metal. Magnetic separation can effectively separate copper-containing minerals and iron concentrate. In the overall process, the recovery efficiency of copper metal has been significantly improved, reducing the common copper loss phenomenon in traditional processes. At the same time, while recovering iron metal from the smelting slag tailings, the extraction of copper is also taken into account, which can not only achieve the efficient utilization of resources, but also reduce the environmental burden and promote sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a flowchart of the overall process method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0025] See Figure 1 , a processing technology for recovering iron metal and copper metal from smelting copper slag tailings, including the following steps:

[0026] S1. Input the flotation tailings slurry into the primary cylindrical magnetic separator through the tailings transfer pump for preliminary magnetic separation to separate the magnetic separation tailings and magnetic separation concentrate; the primary cylindrical magnetic separator adopts a semi-countercurrent trough structure.

[0027] S2. The magnetic separation tailings flow into the tailings tank by gravity, and the magnetic separation concentrate flows into the tower mill for regrinding treatment by gravity.

[0028] S3. The discharge of the tower mill goes to the tower mill discharge pump pool, and then is pumped into the cyclone by the discharge pump for classification. The underflow of the cyclone returns to the tower mill for circulating grinding, and the overflow of the cyclone enters the flotation cell for flotation operation.

[0029] S4. The froth slurry generated in the flotation cell enters the concentrate tank, and then is sent to the flotation cell by a concentrate pump for further separation. Then, the flotation underflow slurry in the flotation cell is input into the flotation underflow pump sump, and after the flotation cell underflow enters the flotation underflow pump sump, it is sent to a secondary cylindrical magnetic separator by a flotation discharge pump for further magnetic separation. At the same time, a part of the non-flotation underflow slurry in the flotation cell is sent to the middlings flotation pump sump. The secondary cylindrical magnetic separator also adopts a semi-countercurrent tank structure.

[0030] S5. The magnetic separation tailings separated by the secondary cylindrical magnetic separator in step S4 above flow by gravity into the tailings tank, and the magnetic separation concentrate is pumped into a permanent magnetic elutriation concentrator. The iron concentrate slurry separated by the permanent magnetic elutriation concentrator enters the iron concentrate pump sump. Then, the tailings flow by gravity into the tailings tank and are filtered and dewatered in sequence to obtain tailings.

[0031] S6. The iron concentrate slurry in the iron concentrate pump sump in step S5 above is pumped to an iron concentrate ceramic filter press, and iron concentrate is obtained after filtration and dewatering.

[0032] The filtering medium of the ceramic filter press is an alumina ceramic filter plate, and the porosity of the alumina ceramic filter plate is 30%-45%.

[0033] S7. The slurry that enters the middlings flotation cell in step S4 above is sent to the next flotation cell by a middlings flotation pump for flotation, and then is filtered and dewatered in sequence to obtain copper concentrate.

[0034] Furthermore, the feeding methods of the tower mill in step S2 include two optional modes: direct gravity feeding and feeding through a pump sump for transfer pumping.

[0035] Furthermore, the pressure control range of the hydrocyclone classification operation in step S3 is 0.15 - 0.22 MPa, and the classification particle size is such that -0.074 mm accounts for 60% - 85%.

[0036] Furthermore, the magnetic field intensity of the permanent magnetic elutriation concentrator in step S5 is 800 Gs, and the number of concentration times is 2 - 3 times.

[0037] The working principle of the present invention:

[0038] In the present invention, the copper slag tailings slurry delivered by the flotation tailings delivery pump enters the primary drum magnetic separator for preliminary magnetic separation, the magnetic tailings flow by gravity into the tailings tank, the magnetic concentrate flows by gravity into the tower mill for regrinding or flows by gravity into the tower mill discharge pump pool, the tower mill feeding mode includes two optional modes: direct gravity feeding and feeding via a pump pool transfer pump, at the same time, the tower mill discharge is pumped into the cyclone through the tower mill discharge pump, and the cyclone bottom The cyclone overflows into the flotation tank. The pressure control range of the cyclone classification operation is 0.15-0.22MPa, and the classification particle size is -0.074mm, accounting for 60%-85%. The froth of the flotation tank enters the concentrate tank and is pumped to the mill flotation tank for further separation. Then the flotation underflow slurry in the flotation tank is input into the flotation underflow pump pool, and the flotation tank underflow enters the flotation underflow pump pool and is sent to the second flotation tank through the flotation discharge pump. The secondary drum magnetic separator is used for further magnetic separation; at the same time, part of the non-floating underflow slurry in the flotation tank is sent to the middling flotation pump pool, and the slurry entering the middling flotation pool is sent to the next flotation pool for flotation by the middling flotation pump, and then filtered and dehydrated to obtain copper concentrate; the magnetic tailings separated by the secondary drum magnetic separator flow into the tailings tank by gravity, and the magnetic concentrate is pumped into the permanent magnetic elutriation and selection machine, the magnetic field strength of the permanent magnetic elutriation and selection machine is 800Gs, and the number of selections is 2-3 times, and the iron concentrate slurry separated by the permanent magnetic elutriation and selection machine enters the iron concentrate pump pool; then the tailings flow into the tailings tank by gravity, and are filtered and dehydrated in turn to obtain tailings, and the iron concentrate slurry in the iron concentrate pump pool is pumped to the iron concentrate ceramic filter, the filter medium of the ceramic filter is an alumina ceramic filter plate, and the porosity of the alumina ceramic filter plate is 30%-45%, and the iron concentrate slurry is filtered and dehydrated to obtain iron concentrate.

[0039] When the magnetic field strength of the first stage roughing magnetic separation is selected as 1200GS, the grinding fineness is determined to be -0.038mm, accounting for 90.70%. Under this condition, the copper flotation recovery rate is significantly improved, and the Fe grade of the iron concentrate reaches 55.48%;

[0040] When the copper flotation tailings are magnetically separated and concentrated using a magnetic field strength of 800GS, the Fe grade of the iron concentrate is 55.67% and the Fe recovery rate is 80.09%;

[0041] The final process was determined to be rough magnetic separation - concentrate regrinding (-0.038mm content accounts for 90.7%) - flotation - rough and scavenging copper - magnetic separation of copper tailings. The full process was tested in a closed circuit, and copper concentrate with a Cu grade of 0.82% and a Cu recovery rate of 20.69%, iron concentrate with a Fe grade of 55.48% and a Fe recovery rate of 32.96%, and the Fe grade of the tailings was 38.52%.

[0042] The above are only embodiments of the present invention, and do not thus limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present invention.

Claims

1. A processing technology for recovering iron metal and copper metal from smelted copper slag tailings, characterized in that: It includes the following steps: S1. Input the flotation tailing slurry into a primary cylindrical magnetic separator through a tailing transfer pump for preliminary magnetic separation to separate magnetic tailings and magnetic concentrates; S2. The magnetic tailings flow by gravity into a tailing tank, and the magnetic concentrates flow by gravity into a tower mill for regrinding; S3. The discharge from the tower mill goes to the tower mill discharge pump sump, and then is pumped by a discharge pump into a hydrocyclone for classification. The underflow of the hydrocyclone returns to the tower mill for circulating grinding, and the overflow of the hydrocyclone enters a flotation cell for flotation operation; S4. The foam slurry generated in the flotation cell enters a concentrate tank, and then is sent to the flotation cell by a concentrate pump for further separation. Then, the flotation underflow slurry in the flotation cell is input into the flotation underflow pump sump, and after the flotation underflow enters the flotation underflow pump sump, it is sent to a secondary cylindrical magnetic separator by a flotation discharge pump for further magnetic separation; meanwhile, a part of the non-flotation underflow slurry in the flotation cell is sent to the middlings flotation pump sump; S5. The magnetic tailings separated by the secondary cylindrical magnetic separator in step S4 above flow by gravity into the tailing tank, and the magnetic concentrates are pumped into a permanent magnetic elutriation separator. The iron concentrate slurry separated by the permanent magnetic elutriation separator enters the iron concentrate pump sump; then the tailings flow by gravity into the tailing tank and are filtered and dewatered in sequence to obtain tailings; S6. The iron concentrate slurry in the iron concentrate pump sump in step S5 above is pumped to an iron concentrate ceramic filter press, and iron concentrate is obtained after filtration and dewatering; S7. The slurry entering the middlings flotation cell in step S4 above is sent to the next flotation cell by a middlings flotation pump for flotation, and then copper concentrate is obtained after filtration and dewatering in sequence.

2. The processing technology for recovering iron metal and copper metal from smelted copper slag tailings according to claim 1, characterized in that: The feeding methods of the tower mill in step S2 include two optional modes: direct gravity feeding and feeding through a pump sump for transfer pumping.

3. The processing technology for recovering iron metal and copper metal from smelted copper slag tailings according to claim 1 is characterized in that: The pressure control range of the hydrocyclone classification operation in step S3 is 0.15 - 0.22 MPa, and the classification particle size is that -0.074 mm accounts for 60% - 85%.

4. The processing technology for recovering ferrous metal and copper metal from smelting copper slag tailings according to claim 1, characterized in that: The magnetic field intensity of the permanent magnetic elutriation separator in step S5 is 800 Gs, and the number of elutriation times is 2 - 3 times.

5. The processing technology for recovering iron metal and copper metal from smelted copper slag tailings according to claim 1, characterized in that: Both the primary cylindrical magnetic separator in step S1 and the secondary cylindrical magnetic separator in step S4 adopt a semi-countercurrent trough structure.

6. The processing technology for recovering iron metal and copper metal from smelted copper slag tailings according to claim 1, characterized in that: The filtering medium of the ceramic filter press in step S6 is an alumina ceramic filter plate, and the porosity of the alumina ceramic filter plate is 30% - 45%.

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