Hot slag chute and its application in recovering valuable metals in copper slag

Abstract

The present invention provides a hot slag chute and its application in recovering valuable metals in copper slag, wherein the hot slag chute is used for the depletion treatment of hot copper slag during the slow cooling process, is in the shape of an open trough, comprises trough edges arranged oppositely and a trough bottom supporting slag material, the trough edges comprise a first trough edge and a second trough edge; the hot slag chute is connected to the slag discharge port of the smelting system at the top and the slag bag at the bottom, and is provided with a buffer column and a plurality of arc-shaped baffles in sequence from top to bottom. The present invention utilizes the structural design of the hot slag chute to achieve full mixing and reaction of the sulfurized conditioning agent and the hot copper slag during the slag discharge process, and finally achieves the stepwise recovery of valuable metals.

Description

Technical Field

[0001] The invention relates to the field of slag treatment, in particular to a hot slag chute and application thereof in recovering valuable metals in copper slag. Background Art

[0002] Copper slag is the product of the pyrometallurgical copper-nickel-cobalt smelting process. Every ton of refined copper produced produces about 2 to 3 tons of copper slag. The storage of a large amount of copper slag requires the occupation of land or farmland. Its composition is complex and causes varying degrees of pollution to the surrounding environment. However, copper slag contains a large amount of usable resources.

[0003] The current resource utilization of copper slag is mainly based on mineral processing to recover valuable metals and the utilization of tailings as cement and building materials. However, with the promotion and application of modern oxygen-enriched enhanced smelting technology in the copper smelting process, the proportion of valuable metals lost in the oxidized state dissolved in silicates in the smelting slag has increased significantly, while traditional flotation can only have a significant recovery effect on mechanically included copper sulfide particles, and cannot simultaneously recover oxidized copper. At the same time, in the existing copper mineral resources, heavy metals such as lead, zinc and iron often coexist, and are impurities in the copper smelting process and are generally removed in the smelting slag. The existing copper slag recovery does not pay attention to the recovery of lead, zinc and iron, resulting in a waste of lead, zinc and iron resources.

[0004] In the conventional technology, the hot slag chute cannot meet the technical requirements of sufficient mixing and reaction of hot copper slag and sulfurization conditioning agent in the slow cooling process (the slow cooling process includes two stages: slag discharge and slow cooling to room temperature in the slag bag, the same below) in the present invention. In view of this, it is necessary to propose a hot slag chute and its application in recovering valuable metals in copper slag to solve the above problems. Summary of the invention

[0005] The main purpose of the present invention is to provide a hot slag chute and its application in recovering valuable metals in copper slag, so as to achieve full mixing and reaction of hot copper slag and sulfurization conditioning agent during slow cooling.

[0006] To achieve the above-mentioned object, the present invention provides a hot slag chute, which is applied to the depletion treatment of hot copper slag during the slow cooling process, and is in the shape of an open trough, including trough edges arranged oppositely and a trough bottom supporting slag, wherein the trough edges include a first trough edge and a second trough edge; the slag discharge port of the hot slag chute is connected to the slag bag at the bottom of the slag discharge port of the smelting system, and a buffer column and a plurality of arc-shaped baffles are sequentially arranged from bottom to top; wherein the arc-shaped baffles are in the shape of upwardly tilted leaves inclined downward, and are closely connected to the trough edge and the trough bottom; a plurality of the arc-shaped baffles are arranged equidistantly along the trough edge, and any two adjacent arc-shaped baffles are staggered on the first trough edge and the second trough edge, and the number of the arc-shaped baffles is not less than 2;

[0007] The buffer column is fixed to the bottom of the groove and arranged in the center, and the width of the buffer column is greater than the length.

[0008] Furthermore, the spacing between the adjacent arc-shaped baffles on the same side is 0.5-1 m; the distance between the buffer column and the outlet of the hot slag chute is 0.2-0.7 m.

[0009] Furthermore, the arc-shaped baffle and the buffer column are made of refractory materials.

[0010] Furthermore, the height of the arc-shaped baffle and the height of the buffer column are 0.5 to 1 times the height of the groove edge.

[0011] Furthermore, the ratio of the projection length of any of the arc-shaped baffles in the width direction of the hot slag chute to the width of the hot slag chute is 0.3-0.7:1;

[0012] The ratio of the width of the buffer column to the width of the hot slag chute is 0.4-0.7:1.

[0013] The present invention also provides an application of the hot slag chute as described in any one of the above items in recovering valuable metals in copper slag, comprising the following steps:

[0014] The hot copper slag discharged from the slag outlet of the smelting system flows into the hot slag chute from the side where the first arc-shaped baffle is located; the first arc-shaped baffle is the first arc-shaped baffle from top to bottom in the hot slag chute;

[0015] Adding a sulfurizing conditioning agent from the upper part of the opposite side of the first arc-shaped baffle in the hot slag chute to immerse the agent in the hot copper slag;

[0016] The hot copper slag to which the sulfurization conditioning agent is added passes through an arc-shaped baffle and a buffer column, enters a slag bag and is slowly cooled to room temperature to obtain slowly cooled slag;

[0017] The slowly cooled slag is subjected to grinding treatment and flotation treatment in sequence to obtain metal sulfide, alloy and / or zinc ferrite;

[0018] The sulfurization conditioning agent comprises gypsum slag and a carbonaceous reducing agent, the carbonaceous reducing agent comprises fixed carbon, the gypsum slag comprises calcium sulfate, and the molar ratio of the fixed carbon to the calcium sulfate in the sulfurization conditioning agent is 2 to 5:1;

[0019] The sulfur content in the sulfurizing conditioning agent is 1 to 3 times the theoretical sulfur content required to sulfurize all the metal oxides in the hot copper slag into metal sulfides.

[0020] Furthermore, when the sulfurization conditioning agent is composed of gypsum slag and a carbonaceous reducing agent, the mass ratio of the gypsum slag to the carbonaceous reducing agent is 2 to 4:1;

[0021] Furthermore, the chemical composition of the hot copper slag includes, by mass fraction, the chemical composition of the copper slag (wt %): Fe 0-50, Cu 0.2-10, Pb 0.5-5.0, Zn 1.0-5.0.

[0022] Furthermore, the flow rate of the hot copper slag is controlled to be 10-50 t / h, and the adding speed of the sulfurization conditioning agent is controlled to be 5-20 t / h.

[0023] Furthermore, in the step of slowly cooling the hot copper slag to room temperature through the arc-shaped baffle and the buffer column, the slow cooling rate of the hot copper slag is controlled to be 0.5-2°C / min.

[0024] The beneficial effects of the present invention are as follows:

[0025] The present invention provides a hot slag chute used for the depletion treatment of hot copper slag during the slow cooling process. The hot slag chute receives the smelting system and the slow cooling slag bag, and a certain number of raised refractory materials (i.e., arc-shaped baffles and buffer columns, the same below) are built inside along the slag flow direction. The raised refractory materials change the flow mode of the hot fluid, and the hot slag continuously forms vortex turbulence at the raised refractory materials. The sulfurization modulator is added from the turbulent vortex, and with the help of the swirling motion of the fluid, the sulfurization conditioning agent suddenly contacts the high temperature of more than 1200°C of the hot copper slag just out of the furnace, fully contacts and reacts with the hot copper slag, and flows into the slow cooling slag bag after mixing; at the same time, the setting of each raised refractory material can buffer the hot copper slag, prolong the residence time of the copper slag in the chute, and make the sulfurization conditioning agent and the copper slag react completely in the chute. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0027] Figure 1 1 is a schematic diagram of a top view of a hot slag chute according to an embodiment of the present invention;

[0028] Among them, 1 is the slag inlet, 3 and 4 are arc baffles, 3 is the first arc baffle, 2 is the feeding place, 5 is an elliptical cylindrical baffle, 6 is a schematic diagram of the vortex shape formed by the buffer column in the low pressure area, and 7 is a schematic diagram of the vortex shape formed by the arc baffle;

[0029] Figure 2 is the XRD pattern of the slowly cooled slag prepared in Example 1 of the present invention;

[0030] Figure 3 is a SEM image of the slowly cooled slag prepared in Example 1 of the present invention;

[0031] Figure 4 It is a SEM image of the slow-cooling slag prepared in comparative example 1 of the present invention; wherein, Figure a is a physical image of the slow-cooling slag under an electron microscope, Figure b is a schematic diagram of the distribution of zinc elements in the slow-cooling slag under an electron microscope, Figure c is a schematic diagram of the distribution of iron elements in the slow-cooling slag under an electron microscope, Figure d is a schematic diagram of the distribution of sulfur elements in the slow-cooling slag under an electron microscope, Figure e is a schematic diagram of the distribution of oxygen elements in the slow-cooling slag under an electron microscope, Figure f is a schematic diagram of the distribution of silicon elements in the slow-cooling slag under an electron microscope, Figure g is a schematic diagram of the distribution of lead elements in the slow-cooling slag under an electron microscope, and Figure h is a schematic diagram of the distribution of copper elements in the slow-cooling slag under an electron microscope.

[0032] Figure 5 It is a SEM image of the slow-cooling slag prepared in comparative example 2 of the present invention; wherein, Figure a is a physical image of the slow-cooling slag under an electron microscope, Figure b is a schematic diagram of the distribution of zinc elements in the slow-cooling slag under an electron microscope, Figure c is a schematic diagram of the distribution of iron elements in the slow-cooling slag under an electron microscope, Figure d is a schematic diagram of the distribution of sulfur elements in the slow-cooling slag under an electron microscope, Figure e is a schematic diagram of the distribution of oxygen elements in the slow-cooling slag under an electron microscope, Figure f is a schematic diagram of the distribution of silicon elements in the slow-cooling slag under an electron microscope, Figure g is a schematic diagram of the distribution of lead elements in the slow-cooling slag under an electron microscope, and Figure h is a schematic diagram of the distribution of copper elements in the slow-cooling slag under an electron microscope. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be noted that all directional indications (such as up, down, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0035] In addition, in the present invention, the descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0036] Furthermore, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0037] In common technologies, considering the fluidity and temperature distribution of hot copper slag, in order to ensure that the hot copper slag can flow smoothly and does not accumulate too much heat in the chute, the slag outlet of copper smelting slag is usually in the shape of a flat trapezoidal chute. The slag body is the main part of the chute, and its shape is mostly a hollow cone with a large top and a small bottom, and the lower part is a hollow column. This design helps the hot copper slag to flow smoothly in the chute and reduce the impact of the slag on the chute. The hot copper slag falls directly and quickly from the chute, and the copper slag stays in the chute for a short time, so as to improve the slag transportation efficiency.

[0038] The present invention performs a depletion treatment on the hot copper slag in the slow cooling process (the slow cooling process includes two stages: slag discharge and slow cooling in the slag bag to room temperature, the same below) to achieve the enrichment and extraction of valuable metals in the copper slag. How to achieve full mixing and reaction between the hot copper slag and the sulfurization conditioning agent is a technical problem that the conventional technology has never faced.

[0039] When the chute in the commonly used technology is used in this application, the sulfurized conditioning agent flows on the surface during the contact process with the hot copper slag, and cannot be evenly mixed; until the hot copper slag enters the slag bag, the sulfurized conditioning agent floats on the surface and is difficult to settle because the density of the sulfurized conditioning agent is lower than that of the melt. With the temperature drop of the hot copper slag, it is difficult to achieve a full reaction between the sulfurized conditioning agent and the hot copper slag, which seriously affects the subsequent recovery rate of valuable metals and the process production efficiency.

[0040] To solve the above problems, the present invention provides a hot slag chute, which is used for the depletion treatment of hot copper slag during the slow cooling process. It is in the shape of an open trough, including relatively arranged trough edges and a trough bottom supporting the slag, and the trough edges include a first trough edge and a second trough edge.

[0041] according to Figure 1 The top view of the structure of the medium hot slag chute, with the flow direction of the hot copper slag as the length direction to limit the length, width and height of the hot slag chute, the same as below.

[0042] Among them, the flow rate of the hot copper slag can be controlled to 30t / h to adapt to the specifications of the hot slag chute in this application, ensuring that the hot copper slag will not splash or overflow when a turbulent vortex is formed.

[0043] In some embodiments, the material of the trough edge and trough bottom in the hot slag chute needs to have good high temperature resistance and corrosion resistance. For example, in the metallurgical industry, electrolytic copper is used as a material for slag troughs due to its good corrosion resistance and thermal conductivity.

[0044] The hot slag chute is connected to the slag outlet of the smelting system and is connected to the slag bag below. A buffer column and a plurality of arc baffles are arranged from top to bottom.

[0045] Among them, the arc-shaped baffle is in the shape of an upward-curved leaf inclined downward, and is closely connected to the groove edge and the groove bottom; multiple arc-shaped baffles are arranged equidistantly along the groove edge, and any two adjacent arc-shaped baffles are staggered on the first groove edge and the second groove edge, and the number of the arc-shaped baffles is not less than 2.

[0046] The buffer column is fixed to the bottom of the groove and arranged in the center. The width of the buffer column is greater than the length, that is, the cross section of the buffer column in the height direction is elliptical. The number of buffer columns is not less than 1. When the number of buffer columns is greater than 1, the distance between the buffer columns is 0.5-1m.

[0047] In some embodiments, the spacing between the adjacent arc-shaped baffles on the same side is 0.5-1 m; the distance between the buffer column and the outlet of the hot slag chute is 0.2-0.7 m.

[0048] In other embodiments, the distance between the last arc-shaped baffle and the buffer column from top to bottom may be 0.5 m.

[0049] From top to bottom, the distance between the first arc-shaped baffle and the upper end of the hot slag chute can be 0.3~1m.

[0050] Exemplarily, the distance from the first arc-shaped baffle plate to the upper end of the hot slag chute from top to bottom may be 0.3-0.5 m.

[0051] The ratio of the projection length of any arc-shaped baffle in the width direction of the hot slag chute to the width of the hot slag chute is 0.4-0.7:1;

[0052] The ratio of the width of the buffer column to the width of the hot slag chute is 0.4-0.7:1.

[0053] The spacing and width of the raised refractory materials can ensure the existence of eddy currents at the tail end of the arc baffle (the far end of the arc baffle, i.e., the end of the arc baffle away from the connected groove edge) and the lower part of the buffer column, ensuring that Figure 1 The formation of a specific fluid morphology is shown.

[0054] The arc-shaped baffle plate and the buffer column can be made of refractory materials, and the arc-shaped baffle plate and the buffer column can be connected to the groove edge and the groove bottom by snap-fitting.

[0055] In some specific embodiments, Figure 1As shown in the top view of the hot slag chute in one embodiment of the present invention, the hot slag chute is usually inclined at an angle between 45° and 60°, not exceeding 65°, to connect the slag discharge port of the smelting system and the slow cooling slag bag; 1 is the slag inlet, located on the left side of the hot slag chute, 2 is the feeding point, 3 and 4 are arc-shaped baffles, and 5 is a buffer column.

[0056] The molten slag flows out from the slag outlet and enters the hot slag chute through the slag inlet 1. Due to the obstruction of the arc baffle 3, the hot copper slag flows along the arc baffle and forms turbulence near the end of the arc baffle, i.e., the feeding point 2. The sulfidation conditioning agent is added from the feeding point 2 and mixed with the hot copper slag. With the help of the large amount of heat released by the hot copper slag, the molten slag passes through the arc baffle 4 and the buffer column 5 to further promote the mixing of the hot copper slag and the sulfidation conditioning agent, and prolong the residence time of the hot copper slag in the chute, so that the sulfidation conditioning agent and the hot copper slag react as completely as possible in the hot slag chute and then enter the slow cooling slag bag, slowly cooled to room temperature, and finally achieve copper and lead enrichment in the form of metal matte and alloy, zinc and iron enrichment mainly in the form of zinc ferrite, the slag is crushed and finely ground, and then the sulfide that has not settled completely is recovered by sulfidation flotation, and the flotation tailings are further recovered by secondary flotation to recover zinc ferrite.

[0057] In some embodiments, the hot slag chute may have a length of 1-3 m, a height of 0.2-1 m, and a width of 0.5-1.5 m.

[0058] In other embodiments, the height of the arc-shaped baffle and the buffer column is 0.5 to 1 times the height of the groove edge. Preferably, the height of the arc-shaped baffle and the buffer column is consistent with the height of the groove edge.

[0059] The present invention also provides the use of the hot slag chute as described in any one of the above items in recovering valuable metals in copper slag, comprising the following steps:

[0060] S1. The hot copper slag discharged from the slag outlet of the smelting system flows into the hot slag chute from the side where the first arc-shaped baffle is located; the first arc-shaped baffle is the first arc-shaped baffle from top to bottom in the hot slag chute.

[0061] S2. Add the sulfurization conditioning agent from above the first arc-shaped baffle and from the opposite side of the first arc-shaped baffle in the hot slag chute, and immerse it in the hot copper slag.

[0062] The sulfur content in the sulfurizing conditioning agent is 1 to 3 times the theoretical sulfur content required to sulfidize all the metal oxides in the slag into metal sulfides.

[0063] In some embodiments, when the sulfurization conditioning agent is composed of gypsum slag and a carbonaceous reducing agent, the mass ratio of the gypsum slag to the carbonaceous reducing agent is 2 to 4:1;

[0064] The sulfurization conditioning agent comprises gypsum slag and a carbonaceous reducing agent, wherein the carbonaceous reducing agent comprises fixed carbon, the gypsum slag comprises calcium sulfate, and the molar ratio of the fixed carbon to the calcium sulfate in the sulfurization conditioning agent is 2-5:1.

[0065] In terms of mass fraction, the chemical composition (wt%) of the copper slag may be: Fe 0-50, Cu 0.2-10, Pb 0.5-5.0, Zn 1.0-5.0.

[0066] For example, the chemical composition of the copper slag, measured by mass fraction (wt%), may be: Fe 10-45, Cu 0.2-10, Pb 0.5-5.0, Zn 1.0-5.0.

[0067] Gypsum slag and carbonaceous reducing agent are combined to carry out sulfidation reduction of metal oxides in copper slag, and finally lead, zinc and copper are enriched in the form of metal matte and alloy, and zinc and iron are mainly enriched in the form of zinc ferrite, and finally the valuable metals of copper smelting slag are recovered in stages, and the gypsum slag is recycled by treating waste with waste. The method is simple to operate and has high reaction efficiency. It can use the latent heat of copper slag to quickly realize the recycling, reduction and harmlessness of copper smelting slag and gypsum slag.

[0068] The specific sulfurization-reduction reaction occurring in the present invention includes:

[0069] Oxidized valuable metals (MeO) in copper smelting slag and CaSO in gypsum solid waste 4 A series of reduction-sulfurization reactions will occur to generate valuable metal sulfides [MeS]:

[0070] (MeO)+CaSO 4 +4C=[MeS]+(CaO)+4CO(g)

[0071] (MeO)+CaSO 4 +4CO(g)=[MeS]+(CaO)+4CO 2 (g)

[0072] As the reaction temperature of the materials increases, sulfate [MeSO 4 ] will continue to decompose in a reducing atmosphere to generate the corresponding metal sulfide [MeS]:

[0073] [MeSO 4 ]+4C=[MeS]+4CO(g)

[0074] [MeSO 4 ]+2CO(g)=[MeS]+2CO 2 (g)

[0075] Metal sulfides Copper sulfide oxide:

[0076] [MeS]+CuO=[CuS]+MeO

[0077] Iron oxides and silicates in copper smelting slag will also be reduced and sulfided to [FeS], and further sulfided metal oxides in the slag:

[0078] (MeO)+[FeS]=[MeS]+(FeO)

[0079] Under a strong reducing atmosphere, the metal oxides (MeO) in the smelting slag will also be reduced to metal elements and enter the matte phase:

[0080] (MeO)+C=[Me]+CO(g)

[0081] (MeO) + CO(g) = [Me] + CO 2 (g)

[0082] In other embodiments, Figure 1 As shown in the top view of the hot slag chute in the present invention, the feeding point 2 is located at the upper part of the tail end of the first arc-shaped baffle, that is, the upper part of the opposite side. The arc-shaped baffle can change the flow mode of the hot copper slag to form a vortex and turbulence. The sulfurization conditioning agent is added from the turbulent vortex (i.e., the feeding point 2) formed by the first arc-shaped baffle, and the sulfurization conditioning agent and the hot copper slag can be fully mixed with each other by means of the swirling motion of the melt.

[0083] S3. The hot copper slag to which the sulfurization conditioning agent is added passes through an arc-shaped baffle and a buffer column, enters a slag bag and is slowly cooled to room temperature to obtain slowly cooled slag.

[0084] In some embodiments, the addition rate of the sulfurization conditioning agent is controlled to be 4-20 t / h. Preferably, the addition rate of the sulfurization conditioning agent can be 4.5 t / h.

[0085] The raised refractory material changes the flow mode of the hot fluid, and the hot slag continuously forms vortex turbulence at the raised refractory material. The sulfurization modulator is added from the turbulent vortex, and with the help of the swirling motion of the fluid, the sulfurization modifier suddenly contacts the high temperature of more than 1200°C of the hot copper slag just out of the furnace, fully contacts and reacts with the hot copper slag, and flows into the slow cooling slag bag after mixing; at the same time, the setting of each raised refractory material can buffer the hot copper slag, prolong the residence time of the copper slag in the chute, and make the sulfurization modifier and the copper slag react completely in the chute, solving the defects existing in the application of the common technology and the present invention: the contact process of the sulfurization modifier and the hot copper slag flows on the surface and cannot be evenly mixed; and due to the density difference and temperature drop, the sulfurization modifier in the subsequent slow cooling bag also floats on the surface of the hot copper slag and is difficult to immerse, and the full reaction between the sulfurization modifier and the hot copper slag is difficult to achieve, which seriously affects the reaction effect of the sulfurization modifier and the metal oxide and the growth effect of the metal sulfide, and the recovery rate of the valuable metal and the process production efficiency are difficult to guarantee.

[0086] Among them, the vortex shape of hot copper slag has the following effects on the addition of sulfurization conditioning agent:

[0087] Strengthen the mixing effect of sulfurization conditioning agent and melt: The vortex forms a strong flow and mixing effect inside the hot copper slag through its unique rotation and stirring effect, so that the sulfurization conditioning agent can be dispersed into the hot copper slag faster and more evenly; and the vortex can reduce the mass transfer resistance and improve the reaction efficiency, so that the sulfurization conditioning agent can play its role more effectively. In addition, the vortex can reduce the loss of sulfurization conditioning agent during the addition process and reduce the waste caused by agglomeration or precipitation.

[0088] After the uniform mixing and mass transfer process in the hot slag chute, the sulfiding conditioning agent fully reacts with the metal oxides in the hot copper slag. After entering the slag bag, the hot slag with the sulfiding conditioning agent is slowly cooled to room temperature. During this process, the metal sulfide particles continue to aggregate and grow during the slow cooling process, reaching the particle size requirement (>40μm) that is conducive to subsequent grinding-flotation.

[0089] In other embodiments, the slow cooling rate of the hot copper slag can be controlled to 0.5-2°C / min, which is beneficial to the enrichment and sedimentation of sulfide particles.

[0090] S4. The slowly cooled slag is subjected to grinding treatment and flotation treatment in sequence to obtain metal sulfide, alloy and / or zinc ferrite.

[0091] The slowly cooled slag is crushed, finely ground, and then recovered by sulfide flotation. The recovered metal matte / alloy (sulfides and alloys such as copper, lead, zinc, and iron) is sent to the next step of blowing for further recovery, and the slag flotation tailings are then washed again to recover zinc ferrite and magnetite.

[0092] In some embodiments, the grinding may include the steps of: coarse crushing of the copper slag, fine crushing, and ball milling to -80 to -200 mesh.

[0093] In other embodiments, flotation may include the following steps: adding flotation reagents to the copper slag after grinding to allow the matte particles to sink to the bottom, thereby separating the matte from the slag.

[0094] For further understanding of the present invention, examples are given below:

[0095] Example 1

[0096] Gypsum slag and coke are mixed in a mass ratio of 4:1. The chemical composition (wt%) of the gypsum slag is: Ca 28.0, Mg 0.49, K 0.033, Fe 0.11, Cd 0.010, Cu 0.0005, S 19.00, Pb 0.011; the chemical composition (wt%) of the coke is: C 84.00, H 5.11, S 2.85, N 1.32. Grind and mix thoroughly with an agate mortar to form a sulfurizing conditioning agent; take 5000g of bottom-blown slag from a smelter, the chemical composition (wt%) of the hot copper slag is: Fe 40.13, Cu 3.25, Pb 1.03, Zn3.65, Ca 2.61, Si 11.59, put it into a muffle furnace and heat it to 1300°C with the furnace, let the molten copper slag pass through the hot slag chute, and at the same time take 1000g of sulfurizing conditioning agent and add it to the molten copper slag through the feeding port, keep the cooling rate at 1.0°C / min, and cool it to room temperature to obtain slow-cooling slag.

[0097] The total length of the hot slag chute is 2m, the distance between the arc baffles opposite to each other on opposite sides is 0.5m; the distance between the buffer column and the outlet of the hot slag chute is 0.5m, the distance between the first arc baffle and the upper end of the hot slag chute is 0.5m, the distance between the last arc baffle and the buffer column is 0.5m, the height of the arc baffle and the buffer column is consistent with the height of the chute edge, and the ratio of the projection length of any arc baffle in the width direction of the hot slag chute to the width of the hot slag chute is 0.5:1;

[0098] The ratio of the width of the buffer column to the width of the hot slag chute is 0.4:1, the flow rate of the hot copper slag is controlled to be 30 t / h, and the addition rate of the sulfurization conditioning agent is controlled to be 4.8 t / h.

[0099] Figure 2 The XRD test results show that the main phases of the smelting slag after melting and slow cooling are ferrous silicate and ferroferric oxide, and the main component of the matte phase is Cu 39 S 28 , FeS, Fe 3 S 4The above substances can be effectively recovered in the subsequent mineral processing stage.

[0100] Figure 3 The SEM images in the test results show that 90% of the particle sizes of Cu-Fe-S matte particles and Fe-S sulfides are greater than 100μm, which can be efficiently recovered in sulfide flotation; at the same time, there is a clear boundary between the above sulfides and the Fe-O-Si-Ca slag phase, which is conducive to the dissociation of mineral monomers. It is calculated that the enrichment rate of copper, lead and zinc in sulfides is greater than 92.6%.

[0101] Comparative Example 1

[0102] Gypsum slag and coke are mixed in a mass ratio of 5:1. The chemical composition (wt%) of the gypsum slag is: Ca 28.0, Mg 0.49, K 0.033, Fe 0.11, Cd 0.010, Cu 0.0005, S 19.00, Pb 0.011; the chemical composition (wt%) of the coke is: C 92.00, H 3.11, S 1.85, N 1.32. Grind and mix thoroughly with an agate mortar to form a sulfurized conditioning agent; take 100g of slow-cooled slag from a smelter in Shandong, the chemical composition (wt%) of the copper slag is: Fe 40.13, Cu 3.25, Pb 1.03, Zn3.65, Ca 2.61, Si 11.59, put it into a crucible, add 10g of sulfurized conditioning agent on the top layer, heat to 1300℃, react for 1h, it can be seen that the sulfurized conditioning agent floats on the surface of the hot copper slag and is difficult to immerse, maintain the cooling rate at 1.0℃ / min, cool to room temperature to obtain slow-cooled slag.

[0103] Figure 4 The SEM image test results show that the particle size of Cu-Fe-Pb-S matte particles and Fe-S sulfides is small, and the aggregation effect is not obvious; at the same time, the conversion of oxidized copper and iron to sulfides is not realized and cannot be recovered by flotation.

[0104] Comparative Example 2

[0105] Gypsum slag and coke are mixed in a mass ratio of 5:1. The chemical composition (wt%) of the gypsum slag is: Ca 28.0, Mg 0.49, K 0.033, Fe 0.11, Cd 0.010, Cu 0.0005, S 19.00, Pb 0.011; the chemical composition (wt%) of the coke is: C 92.00, H 3.11, S 1.85, N 1.32. Grind and mix thoroughly with an agate mortar to form a sulfurized conditioning agent; take 100g of slow-cooled slag from a smelter in Shandong, the chemical composition of the copper slag (wt%) is: Fe 40.13, Cu 3.25, Pb 1.03, Zn3.65, Ca 2.61, Si 11.59, put it into a crucible, add 20g of sulfurized conditioning agent on the top layer, heat to 1300℃, react for 1h, it can be seen that the sulfurized conditioning agent floats on the surface of the hot copper slag and is difficult to immerse, maintain the cooling rate at 1.0℃ / min, cool to room temperature to obtain slow-cooled slag.

[0106] Figure 5 The SEM image test results show that the particle size of Cu-Fe-Pb-S matte particles and Fe-S sulfides is small, and the aggregation effect is not obvious; at the same time, the conversion of oxidized copper and iron to sulfides is not realized and cannot be recovered by flotation.

[0107] The above technical solutions of the present invention are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereto. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the protection scope of the present invention.

Claims

1. Application of a hot slag chute in recovering valuable metals in copper slag, characterized in that: The hot slag chute is used for the depletion treatment of hot copper slag during the slow cooling process, and is in the shape of an open trough, including trough edges arranged opposite to each other and a trough bottom supporting the slag material, wherein the trough edges include a first trough edge and a second trough edge; The hot slag chute is connected to the slag outlet of the smelting system and is connected to the slag bag below. A buffer column and a plurality of arc-shaped baffles are arranged in sequence from bottom to top. The arc-shaped baffle is in the shape of an upwardly tilted leaf, closely connected to the groove edge and the groove bottom; a plurality of the arc-shaped baffles are arranged equidistantly along the groove edge, and any two adjacent arc-shaped baffles are staggered on the first groove edge and the second groove edge, and the number of the arc-shaped baffles is not less than 2; The buffer column is fixed to the bottom of the groove and arranged in the center, and the width of the buffer column is greater than the length; The application of the hot slag chute in recovering valuable metals in copper slag comprises the following steps: The hot copper slag discharged from the slag outlet of the smelting system flows into the hot slag chute from the side where the first arc-shaped baffle is located; the first arc-shaped baffle is the first arc-shaped baffle from top to bottom in the hot slag chute; Adding a sulfurizing conditioning agent from the upper part of the opposite side of the first arc-shaped baffle in the hot slag chute to immerse the agent in the hot copper slag; The hot copper slag to which the sulfurization conditioning agent is added passes through an arc-shaped baffle and a buffer column, enters a slag bag and is slowly cooled to room temperature to obtain slowly cooled slag; The slowly cooled slag is subjected to grinding treatment and flotation treatment in sequence to obtain metal sulfide, alloy and / or zinc ferrite; The sulfurization conditioning agent comprises gypsum slag and a carbonaceous reducing agent, the carbonaceous reducing agent comprises fixed carbon, the gypsum slag comprises calcium sulfate, and the molar ratio of the fixed carbon to the calcium sulfate in the sulfurization conditioning agent is 2 to 5:1; The sulfur content in the sulfurizing conditioning agent is 1 to 3 times the theoretical sulfur content required to sulfurize all the metal oxides in the hot copper slag into metal sulfides.

2. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The distance between the adjacent arc-shaped baffles on the same side is 0.5-1 m; the distance between the buffer column and the outlet of the hot slag chute is 0.2-0.7 m.

3. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The arc-shaped baffle and the buffer column are made of refractory materials.

4. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The height of the arc baffle and the buffer column is 0.5 to 1 times the height of the groove edge.

5. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The ratio of the projection length of any arc-shaped baffle in the width direction of the hot slag chute to the width of the hot slag chute is 0.3-0.7:1; The ratio of the width of the buffer column to the width of the hot slag chute is 0.4-0.7:

1.

6. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: In the case where the sulfurization conditioning agent is composed of gypsum slag and a carbonaceous reducing agent, the mass ratio of the gypsum slag to the carbonaceous reducing agent is 2-4:

1.

7. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: Measured by mass fraction, the chemical composition of the hot copper slag includes, measured by mass fraction, the chemical composition of the copper slag (wt %) is: Fe 0-50, Cu 0.2-10, Pb 0.5-5.0, Zn 1.0-5.

0.

8. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The flow rate of the hot copper slag is controlled to be 10-50 t / h, and the adding speed of the sulfurization conditioning agent is controlled to be 4-20 t / h.

9. The use of the hot slag chute according to claim 1 in recovering valuable metals in copper slag, characterized in that: The hot copper slag passes through the arc-shaped baffle and the buffer column and enters the slag bag to be slowly cooled to room temperature. In the step of obtaining slowly cooled slag, the slow cooling rate of the hot copper slag is controlled to be 0.5-2°C / min.

Images