Copper smelting slag treatment method and system based on rapid holding and slow cooling

Abstract

This application belongs to the field of metallurgical solid waste resource utilization, and more specifically, relates to a method and system for treating copper smelting slag based on rapid heat preservation and slow cooling technology. The method involves using casting slag with dispersed pores inside the casting to collect high-temperature molten slag in front of the furnace, and then using a heat preservation device to maintain the temperature and slow cool for more than 8 hours. This promotes the sedimentation, aggregation, growth, and maturation of copper-containing particles, significantly increasing the average particle size of copper. After slow cooling, the liquid slag is transferred to an air-quenching heat collection chamber for air quenching and granulation, and the high-temperature flue gas is used for waste heat recovery (for copper concentrate drying, hot steam, or waste heat power generation, etc.). The granulated slag, after cooling and conveying, directly enters the ball mill flotation system, eliminating the need for multi-stage crushing processes and achieving energy saving, consumption reduction, and increased copper recovery rate. This invention realizes large-scale, intelligent, energy-saving, and maximized resource recovery in copper smelting slag treatment, increasing copper recovery rate by 8-15%, saving energy by 30-40%, and shortening the cooling cycle by more than 60 hours.

Description

Technical Field

[0001] This application belongs to the field of metallurgical solid waste resource utilization, and more specifically, it relates to a copper smelting slag treatment method and system based on rapid heat preservation and slow cooling technology, especially a new high-efficiency treatment process and system for copper smelting slag based on large-scale casting slag bags and heat preservation and slow cooling, which is suitable for continuous, intelligent and green treatment of high-temperature molten slag in copper smelting process, realizing efficient recovery of copper resources and comprehensive utilization of waste heat. Background Technology

[0002] In the copper smelting process, high-temperature copper smelting slag at 1200-1400℃ is continuously discharged from the smelting furnace and the blowing furnace. The copper grade in this slag is typically higher than that of the copper ore used for beneficiation; therefore, achieving the safe and efficient recovery of copper resources from this slag is of great significance. Currently, the traditional process commonly used in the industry involves using a 12m... 3 Slag ladles of various sizes, receiving high-temperature molten slag, are typically subjected to several days of slow cooling in the slag yard, if site and slag conditions permit, to promote the full growth of copper particles. However, this method results in low slag ladle turnover efficiency, large space requirements, and a tendency for high copper content in the tailings. To improve efficiency and shorten the production cycle, the widely adopted improved process involves transporting the slag ladle to the slag yard and subjecting it to approximately 8-24 hours of natural slow cooling, followed by water injection for in-ladle water cooling, with the total processing time controlled to around 72 hours. After the slag has completely solidified, it is then transferred to the slag dump for unloading, and subsequently undergoes mechanical crushing, screening, multi-stage grinding, and flotation processes to ultimately recover matte or metallic copper from the slag, achieving resource utilization.

[0003] In slag ladles used to handle high-temperature copper smelting slag (1200-1400℃), common types include welded ladles (also known as structural ladles) and cast ladles. In practical industrial applications, cast ladles are generally considered prone to casting defects such as shrinkage cavities, porosity, sand holes, and gas holes during manufacturing; while welded ladles, formed from dense steel plates, do not have porosity issues. Therefore, welded ladles are typically preferred as insulation and slow-cooling containers for high-temperature copper smelting slag. Even when using cast slag ladles, considering that defects such as shrinkage cavities and porosity from the casting process may affect their mechanical properties, industry technicians usually optimize casting process parameters to control these defects in non-working areas such as risers and gating systems, thereby specifically avoiding shrinkage cavities and porosity defects on the ladle walls.

[0004] However, the above-mentioned traditional process has the following prominent problems: (1) The natural slow cooling of the slag yard and the water cooling in the ladle together take about 72 hours, which results in the slag ladle being occupied for a long time, with a long cooling cycle, low equipment turnover rate, and the need for a large number of slag ladles and a large area of ​​slow cooling space; (2) During the water cooling process of copper smelting slag in the ladle, the high-temperature melt is prone to violent reaction when it comes into contact with water, which can cause safety hazards such as blasting and explosion; (3) Using 12m3 The small slag bag cools slowly and has a fast heat dissipation rate, which leads to the premature formation of dendritic structures and insufficient growth of copper particles. In particular, the instantaneous solidified shell at the bag wall and the bag opening is relatively thick (the copper particles in this part basically cannot grow), resulting in a high copper content in the tailings of the slag beneficiation. (4) The huge sensible heat carried by the high-temperature slag is not effectively recovered and is dissipated through natural heat dissipation or water cooling, causing thermal pollution and serious energy waste. (5) The slag after slow cooling has a large size, so the beneficiation process needs to go through coarse crushing-medium crushing-fine crushing-screening-coarse grinding-fine grinding-flotation, or coarse crushing-semi-autogenous grinding-ball milling (one or two stages)-flotation, etc., which is a long process. Summary of the Invention

[0005] The purpose of this invention is to overcome the technical defects in existing copper smelting slag treatment processes, such as long cooling cycles, low equipment turnover rates, large site occupancy, insufficient crystal growth of copper particles in slag, high copper content in tailings, long mineral processing flow, and serious energy waste. This invention provides a new high-efficiency process and system for copper smelting slag based on large-scale slag bags, heat preservation and slow cooling technology, and air quenching granulation treatment, so as to achieve high efficiency, energy saving, intelligence and maximum resource recovery in the slag treatment process.

[0006] To achieve the above objectives, in a first aspect, this application provides a copper smelting slag treatment system based on rapid heat preservation and slow cooling, comprising: a casting slag bag, a heat preservation device, an air quenching heat collection chamber, a waste heat recovery device, and a mineral processing device.

[0007] The casting slag bag is used to receive molten copper smelting slag at a slag discharge temperature of 1200-1400℃; the casting of the slag bag has a diffusely distributed porous structure inside to reduce the thermal conductivity of the casting slag bag and improve the heat preservation effect.

[0008] The heat preservation device is used to keep the molten copper smelting slag in the casting slag bag warm and cool it slowly; the heat preservation device can keep the heat preservation temperature in the casting slag bag between the slag receiving temperature and 1205℃.

[0009] The air quenching heat collection chamber is used to air quench and granulate the liquid molten copper smelting slag after the heat preservation and slow cooling process is completed.

[0010] The waste heat recovery device is used to recover the heat generated during the air quenching process;

[0011] The mineral processing device is used to grind the copper smelting slag obtained by air quenching and granulation, and to recover copper concentrate by flotation.

[0012] Preferably, the heat preservation device includes a covering agent placed inside the casting slag bag and on the surface of the molten copper smelting slag, a heat preservation cover placed at the opening of the casting slag bag, and a heat preservation chamber for holding the slag bag.

[0013] Preferably, the covering agent is a composite covering agent, which is a mixture of carbon-based materials and aluminum silicate-based materials, with a thickness of 50-100mm; the insulation cover is a composite insulation cover, which includes: a heat-resistant steel frame and insulation material with a heat-reflective coating on the surface; the insulation chamber adopts a split structure of a main box body + an automatically opening and closing top cover, with a total volume slightly larger than the slag containment volume to meet placement requirements, while retaining gaps for hoisting, temperature measurement, and ventilation. Both the box body and the top cover are four-layer composite structures, consisting of: a steel frame, insulation material, a high-temperature resistant insulation board, and a steel frame, from the inside out.

[0014] Preferably, during the casting process of the casting slag pot, by setting external chills in the conical area of ​​the inner and outer walls of the slag pot, a fine pore structure is diffusely distributed in the middle part of the wall thickness direction of the casting slag pot, and the size of the fine pores is <0.1mm.

[0015] Preferably, the casting slag bag has a volume of 12-30 m³. 3 Further preferred is 18-30m 3 Large-capacity foundry slag bag.

[0016] Preferably, the casting process of the casting slag pot adopts an inverted pouring method, that is, the bottom is on top and the slag pot opening is at the bottom, and the initial solidification temperature of the casting is controlled at 1480-1540℃ during the pouring process.

[0017] According to another aspect of the present invention, a method for treating copper smelting slag using the aforementioned treatment system is provided, comprising the following steps:

[0018] (1) A casting slag bag is used to collect molten copper smelting slag with a slag discharge temperature of 1200-1400℃; the casting of the slag bag has a diffusely distributed pore structure inside to reduce the thermal conductivity of the casting slag bag.

[0019] (2) After receiving the slag, the casting slag bag is kept warm by the heat preservation device, so that the molten copper smelting slag is kept warm and cooled slowly in the slag bag; the heat preservation temperature is between the slag receiving temperature and 1205℃, so that the copper-containing droplets continue to settle, collide and aggregate under the action of gravity, thereby achieving macro segregation and coarsening of copper particles.

[0020] (3) The liquid molten copper smelting slag that has been heat-insulated and slow-cooled is quenched and granulated by air to obtain solid copper smelting slag; and the heat generated during the air quenching process is recovered as waste heat.

[0021] (4) After cooling the solid copper smelting slag obtained by air quenching, it is ground and then flotated to recover copper concentrate.

[0022] Preferably, within one hour before the end of the heat preservation and slow cooling in step (3) and before the air quenching, the outer wall of the slag bag and the trunnion are cooled with air as the cooling medium, so that the temperature of the outer surface of the slag bag drops to ≤250℃, and its mechanical strength is restored.

[0023] Preferably, step (4) specifically involves: hoisting the cooled slag bag to a mobile hydraulic tilting platform, and by adjusting the tilting angle and speed, smoothly introducing the liquid slag into the air quenching heat collection chamber through a high-temperature resistant chute;

[0024] In the air quenching heat collection chamber, a pressure of 0.6-1.0 MPa and a flow rate of 140-180 m³ / h are used. 3 High-pressure gas at a rate of / min is used to quench and granulate the liquid slag, forming granulated slag with a particle size of less than 3mm. At the same time, the high-temperature flue gas is collected and used for copper concentrate drying, steam generation, or waste heat power generation.

[0025] More preferably, the high-pressure gas is compressed air or high-pressure nitrogen. More preferably, the high-pressure nitrogen is derived from waste nitrogen discharged from the oxygen production station of a copper smelter, with a nitrogen purity of ≥95% and containing ≤5% oxygen.

[0026] More preferably, the grinding process specifically involves: directly ball milling the granular copper smelting slag obtained after air quenching to achieve a slurry particle size of -200 mesh ≥ 80wt%, followed by flotation to recover copper concentrate.

[0027] To address the prominent problems of traditional processes and improve the clean production and comprehensive and efficient utilization of copper smelting slag, this invention develops a new process and system for the efficient treatment of copper smelting slag, integrating a large slag ladle for slag remelting, heat preservation and slow cooling, air quenching and cooling, waste heat utilization, and intelligent scheduling. Overall, compared with existing technologies, the technical solutions conceived in this application have the following beneficial effects:

[0028] (1) Shortened cooling cycle: By using a casting slag ladle with low thermal conductivity and a multi-layer insulation structure, the high-temperature liquid phase (above 1205℃) of the copper smelting slag is maintained for a period of time. The molten copper smelting slag is kept warm and slowly cooled for 4-24 hours, preferably 8-12 hours, which enables the full growth of matte particles. This eliminates the need for the traditional 60-hour water cooling in the ladle and allows for direct air quenching and granulation of the molten copper smelting slag after the slow cooling is completed. By replacing the traditional 72-hour natural cooling + water cooling with 8-12 hours of controllable heat preservation and slow cooling, the total cooling time is shortened by more than 60 hours, achieving efficient and continuous production.

[0029] (2) Air quenching granulation replaces water cooling for safe and efficient processing: The heat preservation and slow cooling technology of this invention promotes the rapid settling and aggregation of copper particles in the high-temperature molten slag. At the end of heat preservation and slow cooling, more than 90% of the slag is in liquid state, making it possible to use high-pressure gas as the air quenching medium to directly perform anhydrous air quenching on the molten copper smelting slag after heat preservation and slow cooling, replacing traditional water cooling. This greatly shortens the slag bale cycle (air quenching only takes about half an hour, but traditional water cooling takes more than 48 hours). Eliminating the in-bale water cooling and using anhydrous air quenching can also eliminate the risk of explosion and "blasting", reduce the thermal alternating stress of the slag bale, avoid cracking, improve safety and equipment life, and also avoid the generation of water cooling wastewater, reduce dust emissions, and achieve full resource utilization of tailings, which is in line with the development direction of green metallurgy. In addition, anhydrous air quenching can also avoid the formation of glassy phase by slag granulation, which leads to high slag particle hardness and increases grinding difficulty.

[0030] (3) Short mineral processing flow: The slag particles after air quenching are small and uniform (particle size ≤ 3mm), which can save the need for multiple stages of crushing and screening and semi-autogenous grinding, reducing energy consumption (saving about 30-40% of electricity) and equipment investment; the shortened process flow also reduces the number of slag bags (the number of slag bags is reduced to 1 / 10), and nitrogen inert protection reduces oxidation, which is conducive to the mineral processing and recovery of copper and iron.

[0031] (4) Improved metal recovery rate: The large-capacity slag bag and the heat preservation and slow cooling stage achieve full aggregation and growth of copper matte particles, increasing the average particle size of copper particles by 30%. Currently, the copper grade of the tailings after slow cooling is about 0.25% (concentrate grade 25%). Using the improved process of this invention, the copper grade of the tailings is below 0.16%, reducing the copper content of the tailings by more than 20%, resulting in significant annual economic benefits. In addition, the iron ore beneficiation recovery rate is low in traditional copper smelting slag treatment processes. The small amount of oxygen in the gas medium of the air quenching process of this invention is also conducive to the oxidation of iron particles in copper smelting slag into magnetic iron(III) oxide. Furthermore, the rapid heat preservation and slow cooling process of this invention is also conducive to the growth of iron particles in smelting slag, thereby improving the magnetic separation recovery rate of iron.

[0032] (5) Energy saving and emission reduction, saving site area and reducing mineral processing cost: The slag particles after air quenching are small and uniform (particle size <3mm), which can save the need for multi-stage crushing and screening and semi-autogenous grinding, thus reducing energy consumption; the use of nitrogen inert protection during air quenching can avoid copper matte oxidation, which is conducive to the mineral processing and recovery of copper and iron, and eliminates the slow cooling field and stockpile, reducing the site area to 1 / 20; the choice of heat preservation slow cooling and air quenching process in this invention not only improves the copper recovery rate, but also realizes waste heat recovery, which is energy-saving and environmentally friendly.

[0033] (6) Significantly improves processing efficiency: In the preferred embodiment, 18-30m is used. 3 Large-capacity slag bags reduce the frequency of slag collection and transportation by more than 50%, significantly improving equipment utilization.

[0034] (7) Achieve efficient energy recovery: Traditional natural slow cooling + in-package water cooling cannot recover and utilize heat. However, the present invention directly quenches liquid slag through the air quenching heat collection chamber, and the heat generated can be centrally recovered. The heat from this high-temperature flue gas can be collected for copper concentrate drying, steam generation, or waste heat power generation.

[0035] (8) Extending Equipment Life: This invention uses a casting ladle with low thermal conductivity for slow cooling of slag. The low thermal conductivity results in a low temperature on the outer wall of the casting ladle. Further installation of an insulation cover and insulation chamber for slow cooling, combined with an insulation chamber ventilation control system, allows the temperature inside the insulation chamber to be controlled below 250℃, keeping the temperature of the slag ladle body below 300℃, ensuring the slag ladle maintains excellent mechanical strength. Furthermore, due to its low thermal conductivity, the 250℃ insulation chamber temperature will not affect the internal temperature change of the slag ladle. This is especially true for 24m... 3 Large-capacity casting slag ladles, with their thicker walls and slower temperature conduction, make it easier to control the slag ladle temperature below 300°C, ensuring greater mechanical strength and avoiding cracking caused by thermal alternating stress in traditional water cooling systems.

[0036] (9) High level of intelligence: full-process intelligent monitoring and dynamic control, reducing manual intervention, improving operational stability and safety, and meeting the requirements for smart factory construction. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the copper smelting slag treatment method provided in the embodiments of this application;

[0038] Figure 2 This is a schematic diagram of the casting slag bag structure and the location of the external chill provided in the embodiments of this application;

[0039] Figure 3 A comparison of the distribution of internal pore structure in castings when there is no external chill in the embodiments of this application and when the casting method is different;

[0040] Figure 4 The relationship between the viscosity of copper slag and temperature, and the relationship between the settling distance of matte and time at 1250℃;

[0041] Figure 5 The morphology of copper slag, the morphological characteristics of copper-containing compounds, and the morphology after aggregation and growth;

[0042] Figure 6 24m 3 The percentage of liquid phase after solidification for 12 hours under insulated conditions in a casting ladle;

[0043] Figure 7 Input models for simulation of different slag bags;

[0044] Figure 8A comparison of the thickness of the solidified crust at different slag bag walls observed on site;

[0045] Figure 9 A comparison diagram showing the copper smelting slag treatment process proposed in this invention and the existing process before the improvement;

[0046] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0047] 1-Spherical slag ladle; 2-Conical slag ladle; 3-External chill; 4-Gating and riser system; 5-Lifting lug assembly. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0049] Unlike traditional approaches, this invention proposes a copper smelting slag treatment system and method based on rapid heat preservation and slow cooling. It utilizes a cast slag ladle for slag collection, specifically leveraging the microscopically dispersed pore structure within the casting to reduce the thermal conductivity of the ladle and enhance its heat preservation and slow cooling effect. Furthermore, the invention employs a heat preservation device to further heat-preserve and slow-cool the ladle after slag collection. This not only provides sufficient time for copper particles in the high-temperature smelting slag to segregate, grow, and mature, significantly increasing the average particle size, but also significantly reduces or even remelts and eliminates the ladle wall and surface crust compared to existing slag ladles, substantially reducing copper loss in the tail slag and improving copper flotation recovery rate, achieving unexpected technical results.

[0050] Specifically, the present invention provides a copper smelting slag treatment system based on rapid heat preservation and slow cooling, comprising: a casting slag bag, a heat preservation device, an air quenching heat collection chamber, a waste heat recovery device, and a mineral processing device.

[0051] The casting slag bag is used to receive molten copper smelting slag at a slag discharge temperature of 1200-1400℃; the casting of the slag bag has a diffusely distributed porous structure inside to reduce the thermal conductivity of the casting slag bag and improve the heat preservation effect.

[0052] The heat preservation device is used to keep the molten copper smelting slag in the casting slag bag warm and cool it slowly; the heat preservation device can keep the heat preservation temperature in the casting slag bag between the slag receiving temperature and 1205℃.

[0053] The air quenching heat collection chamber is used to air quench and granulate the liquid molten copper smelting slag after the heat preservation and slow cooling process is completed.

[0054] The waste heat recovery device is used to recover the heat generated during the air quenching process;

[0055] The mineral processing device is used to grind the copper smelting slag obtained by air quenching and granulation, and to recover copper concentrate by flotation.

[0056] Correspondingly, the present invention also proposes a processing method based on the above-mentioned processing system, such as... Figure 1 As shown, it includes the following steps:

[0057] (1) A casting slag bag is used to collect molten copper smelting slag with a slag discharge temperature of 1200-1400℃; the casting of the slag bag has a diffusely distributed pore structure inside to reduce the thermal conductivity of the casting slag bag.

[0058] (2) After receiving the slag, the casting slag bag is kept warm by the heat preservation device, so that the molten copper smelting slag is kept warm and cooled slowly in the slag bag; the heat preservation temperature is between the slag receiving temperature and 1205℃, so that the copper-containing droplets continue to settle, collide and aggregate under the action of gravity, thereby achieving macro segregation and coarsening of copper particles.

[0059] (3) The liquid molten copper smelting slag that has been heat-insulated and slow-cooled is quenched and granulated by air to obtain solid copper smelting slag; and the heat generated during the air quenching process is recovered as waste heat.

[0060] (4) After cooling the solid copper smelting slag obtained by air quenching, it is ground and then flotated to recover copper concentrate.

[0061] In some embodiments, step (2) specifically involves: after receiving the slag, covering the surface of the molten slag with a capping agent and setting a heat-insulating cover at the mouth of the slag bag; transferring the covered slag bag to a heat-insulating chamber for slow cooling for 4-24 hours, preferably 8-12 hours; the heat-insulating temperature is between the slag receiving temperature and 1205℃, maintaining a high-temperature liquid phase window period, allowing copper-containing droplets to continuously settle, collide, and aggregate under gravity, achieving macroscopic segregation and coarsening of copper particles. "The heat-insulating temperature is between the slag receiving temperature and 1205℃" can be understood in some embodiments as meaning that during the slow cooling process, 80%-90% of the slag temperature is not lower than 1205℃, and can be adjusted adaptively according to actual needs.

[0062] This invention utilizes a casting slag bale with casting pores to slow-cool the slag, reducing the thermal conductivity of the bale, improving its heat preservation effect, promoting the sedimentation, aggregation, and growth of copper particles, and further enhancing the heat preservation and slow-cooling effect with a heat preservation device. Simulation experiments have shown that this measure brings a series of unexpected technical effects, solving the technical problems of existing high-temperature copper smelting slag treatment processes, which are not only long in cycle but also have small average particle size of copper particles after slow cooling, which is not conducive to flotation recovery, resulting in high copper content in the final tailings and low copper recovery rate in copper smelting slag. This invention proposes a completely new technical approach for copper smelting slag treatment processes.

[0063] In some embodiments, the heat preservation device of the present invention includes a covering agent disposed inside the casting slag bag and on the surface of the molten copper smelting slag, a heat preservation cover disposed at the opening of the casting slag bag, and a heat preservation chamber for holding the slag bag.

[0064] The slag bag surface covering agent described in this invention can be a common slag covering agent in the prior art, such as a mixture of carbonized rice husks and a corresponding binder. In some embodiments, the covering agent is a composite covering agent, which is made by mixing carbonaceous materials with a small amount of aluminosilicate materials, and the layer thickness is 50-100 mm. Among them, the carbonaceous materials can be carbonized rice husks (particle size ≤10 mm, accounting for 90-99% of the total mass), and the aluminosilicate materials, such as aluminosilicate fiber cotton, account for 1-10% of the total mass.

[0065] In a preferred embodiment, a composite insulation cover is also provided at the slag bag opening and on the surface of the composite cover agent. The structure of the composite insulation cover, from the outside in, includes a heat-resistant steel frame and insulation material coated with a heat-reflective coating. The insulation material can be insulation cotton or refractory brick. When installed, the heat-resistant steel frame is located on the side away from the slag bag opening, and the insulation material coated with the heat-reflective coating faces the slag bag opening.

[0066] In a preferred embodiment, the insulated chamber for placing the slag bag adopts a split structure of "main body + automatic opening and closing top cover," with a total volume slightly larger than the slag bag volume to meet placement requirements while preserving clearance for hoisting, temperature measurement, and ventilation. Both the body and the top cover employ a four-layer composite structure, from the inside out: an inner steel frame, a middle layer of insulation cotton, an inner lining of high-temperature resistant insulation board, and an outer steel frame. In some embodiments, the middle layer is filled with high-silica fiber cotton with a density of approximately 128 kg / m³ and a total thickness of 200 mm, while the inner lining uses a high-temperature resistant nanoporous insulation board.

[0067] In some embodiments, the high-efficiency insulation chamber can also be equipped with intelligent dynamic control: the insulation chamber adopts a four-layer composite structure and an automatic opening and closing top cover system, which has excellent insulation performance; it is equipped with multi-point thermocouples to monitor the temperature field distribution in real time, ensuring that the insulation temperature is between the slag receiving temperature and the melting point of fir olivine (1205℃), maintaining the high-temperature liquid phase window period, so that copper-containing droplets continue to settle, collide and aggregate under the action of gravity, realizing macro segregation and copper particle coarsening, and improving process controllability and adaptability.

[0068] The dual synergistic insulation structure of the "composite covering agent + insulation cover" of this invention can effectively isolate air and prevent slag oxidation and secondary oxidation loss of copper-containing phase; at the same time, it avoids the formation of a solidified shell layer caused by rapid surface cooling, maintains the fluidity of the liquid phase on the slag surface, promotes the continuous settling of fine copper-containing particles near the ladle opening under the action of gravity, and enhances the aggregation effect of copper-containing particles.

[0069] The sealed slag bags are transported by crane to a high-efficiency insulation chamber for slow cooling. Large-capacity, sealed slag bags are then hoisted into a dedicated insulation chamber for 8-12 hours of controlled slow cooling. The insulation time is dynamically adjusted based on the actual slag discharge temperature, slag composition (Fe / SiO2 ratio, CaO content, etc.), ambient temperature, and the thermal performance of the insulation chamber. Multiple thermocouples are installed inside the insulation chamber to monitor the temperature field distribution in real time, ensuring the slow cooling process is controllable.

[0070] In some embodiments, during the controlled-temperature slow cooling process, the solidified shell on the wall side is thin (<0.5 mm) and has a loose and porous structure, forming a through-through "semi-solid-liquid" channel network, which is conducive to the migration of copper-containing droplets in the residual liquid phase towards the center. The density of the copper-containing phase is higher than that of the slag body, and it follows the Stokes settling law, achieving sufficient gravity settling under long-term heat preservation. During the settling process, the fine copper-containing droplets undergo Brownian motion collisions, aggregate and grow, and under the drive of the concentration gradient, the Ostwald Ripening effect occurs: small particles dissolve, large particles continue to grow, significantly increasing the average particle size of copper-containing particles (which can grow from <10μm to more than 43-100μm), creating favorable conditions for subsequent efficient mineral processing.

[0071] In some embodiments, the present invention further optimizes the heat preservation performance of the slag ladle by controlling the casting process to adjust the distribution of the internal pore structure of the casting. Specifically, during the casting process of the slag ladle, external chills are placed in the conical areas of the inner and outer walls of the slag ladle, causing a dispersed fine pore structure with a pore size of less than 0.1 mm to form in the middle part of the casting in the thickness direction of the ladle wall. Simulation analysis further shows that if an inverted pouring method is used during the casting process, i.e., the bottom of the slag ladle is facing upwards and the ladle opening is facing downwards, and the solidification temperature of the casting is controlled within the range of 1500-1540℃, the resulting dispersed pore structure can more effectively improve the heat preservation and slow cooling effect of the slag ladle.

[0072] According to the formula for calculating effective thermal conductivity , where k eff It is the effective thermal conductivity of the composite material, V f It is the volume fraction of pores or the second phase, k f It is the thermal conductivity of the pores or second phase, k. m It is the thermal conductivity of the matrix material, while k f < <k m The slag pocket formed by casting is not dense, and there are certain pores inside the casting. In contrast, the slag pocket is made of dense forged steel plate and has almost no pores, with only a small amount of pores at the weld. According to the effective thermal conductivity formula, the effective thermal conductivity of the casting slag pocket is lower than that of the welding slag pocket.

[0073] In some casting processes, chills refer to metallic objects (usually made of cast iron, steel, copper, or graphite) with strong cooling capabilities placed inside the sand mold or casting to control the solidification sequence of the casting. Their traditional function is to accelerate solidification in localized areas and, in conjunction with the optimization of casting process parameters, to concentrate shrinkage cavities and porosity defects mainly in the riser and gating areas, thereby minimizing these defects. However, this invention, through simulation and experimental testing, has found that during the production of the casting slag ladle, by specifically designing one or more of the following: the placement of the external chills, the casting method of the slag ladle, the pouring temperature, and the thickness of the slag ladle, a portion of the porous structure can be preserved and distributed within the ladle wall area. This distribution helps reduce the overall thermal conductivity of the slag ladle, thereby enhancing its heat preservation and slow cooling effect on high-temperature copper smelting slag.

[0074] Specifically, this invention features high thermal conductivity external chills on the conical surfaces of the inner and outer walls of the slag ladle mold. These external chills can be a single, continuous piece or multiple pieces arranged in a spliced ​​configuration on the conical surface. Because the ladle wall near the external chill solidifies faster, a fine-grained structure is formed; while the central part of the ladle wall, relatively far from the external chill, solidifies more slowly, resulting in a coarse-grained structure and a microscopically fine, dispersed porous structure, typically less than 0.1 mm in size. Compared to traditional casting processes using internal chills or only locally placing external chills in the hot spot region, the external chill placement method of this invention not only accelerates the overall solidification of the slag ladle but also retains a portion of the fine, dispersed porous structure in the central part of the ladle wall thickness. Thus, while maintaining the strength of the slag ladle, its thermal conductivity is effectively reduced. In a preferred embodiment, by adjusting parameters such as the thickness, material, and distance between the external chill and the sand mold surface, a coarse-grained region of 20-40 mm thickness can be formed in the middle part of the wall thickness direction, accompanied by a fine dispersed pore structure with a size of less than 0.1 mm.

[0075] In some embodiments, during the production process of the casting slag ladle, the present invention involves externally chilling iron in the conical area of ​​the inner and outer walls of the slag ladle, thereby dispersing micropores inside the wall of the casting slag ladle. Figure 2 24m 3 A cross-sectional view of the casting slag ladle during inverted pouring, where 1-spherical surface of the slag ladle; 2-conical surface of the slag ladle; 3-external chill; 4-gating and riser system; 5-lifting lug assembly. The overall casting process is the same as the existing casting process for slag ladles, except that external chills are specifically installed at the inner and outer conical surfaces of the ladle wall to disperse a fine and diffuse porosity structure in the middle part along the thickness direction of the ladle wall.

[0076] In a preferred embodiment, different casting processes are simulated to examine whether external chills are placed in the conical areas of the inner and outer walls of the slag ladle, and to compare the distribution of porosity in the casting when different pouring methods are used. Figure 3As shown, content (a) is inverted casting without external chills; content (b) is upright casting with external chills; content (c) is as follows... Figure 3 The conical area shown is equipped with an external chill and the casting is poured in an inverted position. The external chill is made of carbon structural steel Q235. It can be seen that, in content (a) without an external chill, the internal pore structure of the casting is mainly concentrated in the riser area, and the pores are not dispersed; in content (b) although an external chill is set in the upright pouring method, the pores are mainly distributed at the slag pot opening and bottom; and only when an external chill is set in the conical area of ​​the slag pot and the casting is poured in an inverted position (content (c)) is a large number of fine and dispersed pore structures generated on the slag pot wall (the red area in the figure indicates the pore structure).

[0077] The casting material of the slag ladle used in this invention can be the engineering-grade cast carbon steel commonly used in existing casting ladles, such as ZG230-450, or low-carbon high-strength heat-resistant alloy steel. In some embodiments, the casting material of the slag ladle is: low-carbon high-strength heat-resistant alloy steel as the base material, and the molten steel is modified as needed during the casting process. In a preferred embodiment, the specific composition of the low-carbon high-strength heat-resistant alloy steel, by mass percentage, includes: C: 0.15~0.2%, Si: 0.40~0.80%, Mn: 0.60~1.20%, Cr: 0.9~1.5%, Ni: 0.8~1.75%, Mo: 0.3~0.5%, S ≤ 0.015%, P ≤ 0.015%, RE: 0.001-0.1%, with the balance being Fe and unavoidable impurities.

[0078] This invention also optimizes the initial solidification temperature during the casting process through simulation: controlling the initial solidification temperature within the range of 1480°C to 1580°C, and combining it with numerical simulation of the casting process, the influence of temperature on the evolution of solidification defects was systematically studied. Simulation results show that as the initial solidification temperature decreases, the total volume of shrinkage cavities and porosity inside the casting shows a significant decreasing trend, while the porosity distribution tends to be more dispersed and fine. Through simulation of the slag ladle casting process, this invention shows that the inverted pouring method (bottom up, slag ladle opening down) and controlling the initial solidification temperature of the casting at 1480-1540°C, preferably 1500-1520°C, makes it easier to generate dispersed porosity, thus helping to reduce the thermal conductivity of the slag ladle. According to the Hall-Petch relationship and fracture mechanics theory, reducing the defect size helps to reduce the stress concentration factor, thereby significantly improving the material's resistance to thermal fatigue and cracking. The slag bag structure design of the present invention can effectively reduce the thermal conductivity of the slag bag and promote the aggregation and growth of copper particles while maintaining its mechanical properties.

[0079] This invention, through a composite process of "external chill + low-temperature casting", successfully transforms the shrinkage cavities and porosity defects inside large slag ladles from a concentrated, large-volume form to a dispersed, small form. Without increasing the riser volume or subsequent processing costs, it significantly improves the density and service reliability of castings, demonstrating outstanding creativity, practicality, and industrial application value.

[0080] The rapid heat preservation and slow cooling technology of this invention utilizes a casting slag pot with a volume suitable for various casting volumes, such as 12-30m³. 3 Experiments have shown that large-capacity casting slag bags have better heat storage capacity, smaller specific surface area, and better insulation performance; therefore, 18-30m³ is the optimal choice. 3 Large-capacity foundry slag bag.

[0081] During the experiment of this invention, 12m 3 Welding package, 12m 3 Casting ladle and 24m 3 The heat dissipation specific surface area of ​​the casting ladle was calculated and compared, and the results are shown in Table 1. The heat dissipation specific surface area of ​​each slag ladle is defined as the ratio of the sum of all heat dissipation areas within the slag ladle to the slag volume, where the heat dissipation area includes the outer surface area of ​​the slag ladle and the surface area of ​​the slag in direct contact with air. Calculations show that the welded ladle has a relatively larger surface area due to the presence of multiple welded components; therefore, under the same volume conditions, the specific surface area of ​​the welded ladle is higher than that of the casting ladle. However, when comparing the contents of the casting ladle, the large-capacity casting ladle (24m³) has a higher specific surface area. 3 The specific surface area of ​​the ) is smaller than that of the small-capacity casting ladle (12m). 3 This data further illustrates that large-capacity casting slag ladles dissipate heat more slowly, which is another reason why they have better heat preservation and slow cooling effects compared to small-capacity casting ladles and welding ladles.

[0082] Table 1 Comparison of specific surface area for heat dissipation of different slag bags

[0083]

[0084] In copper smelting slag, copper recoverable by flotation is mainly found in matte particles. Based on the liquidus temperature of matte, its precipitation range is typically 1020-1190℃. However, other phases in the smelting slag precipitate earlier than matte, such as Fe₂SiO₄, Al₂O₃, and SiO₂. Among these, fir olivine (Fe₂SiO₄) has the highest content, accounting for about 80% of the slag phase, with a melting point of 1205℃. Experiments have shown that the faster the slag viscosity increases, the greater the resistance to the migration of matte particles in adjacent regions, and the lower the rate of aggregation and growth. Conversely, if the viscosity increases slowly, the migration of matte particles is less restricted, making them more prone to aggregation and growth. Figure 4As shown. Due to the high content of fir olivine, if it precipitates and forms a dendritic structure, it will rapidly increase the viscosity of the slag, thereby hindering the settling and coarsening of copper particles. Based on the above mechanism, in the preferred embodiment of this application, when performing heat preservation and slow cooling treatment in the slag bag, special emphasis is placed on implementing temperature control and slow cooling within the range of slag receiving temperature to 1205°C, so as to ensure that the slag promotes the growth of matte particles under relatively low viscosity conditions. During this heat preservation and slow cooling process, the relationship between the nucleation and growth behavior of matte particles and the viscosity change is consistent with the precipitation and coarsening process described by the Oswald ripening mechanism.

[0085] In a preferred embodiment, the heat preservation and slow cooling method of the present invention can maintain the temperature inside the heat preservation chamber stably between the slag receiving temperature and the melting point of fir olivine (1205°C), and the high-temperature liquid phase state can be maintained for 8-12 hours. Under these conditions, the primary solid phase, such as high-melting-point fir olivine, preferentially nucleates and precipitates, while the lower-density copper-containing droplets can continue to settle, collide, and aggregate under gravity (following the Stokes sedimentation law), such as... Figure 5 As shown, this process achieves significant macroscopic segregation and promotes copper particle coarsening. After slow cooling treatment using the method of this invention, the average particle size of the copper particles can increase from ≤10 μm to over 75 μm.

[0086] This invention utilizes the fine, dispersed shrinkage defects formed in specific locations during the casting process using casting slag bags. While ensuring the required mechanical properties of the casting, this effectively reduces the thermal conductivity rate, thus creating favorable conditions for the slow cooling and heat preservation of high-temperature molten slag. Based on this, a method and system for treating copper smelting slag based on rapid heat preservation and slow cooling technology is proposed. This method uses the aforementioned casting slag bag for slag collection and heat preservation and slow cooling, maintaining a high-temperature liquid phase window. This promotes the continuous settling, collision, and aggregation of copper-containing droplets under gravity, achieving macroscopic segregation and significant coarsening of copper particles in a short time. Only 8-12 hours of heat preservation and slow cooling are needed to allow copper particles to grow to the size required for flotation. Afterward, the high-temperature molten slag can be directly air-quenched and granulated to obtain granular copper smelting slag. Compared to the lengthy process of approximately 72 hours (natural slow cooling plus water cooling) required by existing technologies using small-volume slag bags, this invention shortens the processing cycle by nearly 60 hours, hence it is called a rapid heat preservation and slow cooling method.

[0087] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0088] In the following specific embodiments, process parameters that are not specified under specific conditions are generally performed under conventional conditions.

[0089] In some embodiments of this invention, the slow cooling process of copper smelting slag is analyzed by combining actual field sampling and numerical simulation, and the effectiveness of the heat preservation and slow cooling method proposed in this invention is verified. The mathematical model adopts the filling and solidification mechanism model commonly used in the art for simulation analysis.

[0090] In some embodiments, a mathematical model of the liquid forming flow field and a corresponding discretization scheme are used to simulate the filling process. Specifically, starting from the Euler equations, the flow behavior of the actual fluid is solved based on the Navier-Stokes equations; by discretizing the energy conservation equations and continuity equations, coupled calculations of flow and heat transfer are achieved, thereby describing the heat transfer phenomena during the filling process. For the solidification process, a mathematical model of the temperature field is used, combined with Fourier's law and the differential equation of heat conduction, and the finite difference method is employed to perform discretization calculations in the time and space dimensions to complete the numerical simulation of the solidification behavior.

[0091] In the following embodiments, experiments and simulations were conducted on high-temperature copper smelting slag. Combined with experimental sampling analysis, the results of 12m were examined and compared. 3 Foundry ladle, 12m 3 Welding package, 24m 3 Casting ladle and 24m 3 The different performances of casting ladle (insulation) in delaying heat dissipation, inhibiting the formation of solidified shell, and promoting the enrichment of copper-containing particles.

[0092] The initial input conditions for the simulation are as follows: the shape of the slag ladle is set to a conical shape plus a spherical shape. The material of the casting ladle is low-carbon high-strength heat-resistant cast steel (C 0.20%, Si 0.60%, Mn 0.80%, Cr 1.0%, Ni 1.5%, Mo 0.4%, S 0.015%, P 0.01%, RE 0.02%, balance Fe), 12m 3 The thickness of the casting ladle gradually changes from 90-135mm, 24m 3 The thickness of the casting ladle gradually changes from 120-145mm; the welding ladle is made of Q345R material, with a wall thickness of 80mm and a bottom thickness of 100mm. The input slag composition is: SiO2 32wt%, FeO 10wt%, Fe2O3 40wt%, Cu 3wt%, S 0.5wt%, Al2O3 5wt%, CaO 5wt%, MgO 4.5wt%.

[0093] Castings: Density [g / cm³] 3 ]:3.500000,thermal conductivity [cal / cm s [℃]: 0.005000, Heat capacity [cal / g] ℃]: 0.195963, initial temperature [℃]: 1250.000000.

[0094] Air: density [g / cm 3 : 0.001210, thermal conductivity [cal / cm s ℃]: 0.000000, heat capacity [cal / g ℃]: 0.240000, initial temperature [℃]: 20.000000.

[0095] Mold: density [g / cm 3 : 1.550000, thermal conductivity [cal / cm s ℃]: 0.000000, heat capacity [cal / g ℃]: 0.260000, initial temperature [℃]: 400.000000, pouring temperature [℃]: 1250.000000, ambient temperature [℃]: 20.000000, critical solid fraction: 0.650000, latent heat [cal / g]: 56.287399, liquidus [℃]: 1200.000000, solidus [℃]: 1020.000000, thermal radiation coefficient: 0.375000, liquid shrinkage rate [1 / ℃]: 0.000028, phase change shrinkage rate: 0.042804.

[0096] Calculate interface parameters (interface heat transfer coefficient, cal / cm 2 s ℃): 12m 3 Casting package, 12m 3 Welding package is: casting / air: 0.023000, casting / mold: 0.023000, air / mold: 0.023000; 24m 3 Casting package is: casting / air: 0.023000, casting / mold: 0.01000, air / mold: 0.023000; 24m 3 Casting package (insulated) casting / air: 0.000100, casting / mold: 0.000100, air / mold: 0.000100.

[0097] Under the comparison conditions, 12m 3 Casting package, 12m 3 Welding package, 24m 3 Casting package means not insulated, and all are cooled by the method of direct slag removal and air cooling; 24m 3 ​3 Casting package and 24m 3 The casting conditions for the casting ladle (insulated) include: external chills are installed on the inner and outer conical surfaces of the ladle wall; the initial solidification temperature during pouring is 1500℃; and inverted pouring is used. This results in fine, dispersed pores inside the ladle wall, with these pores distributed in the middle portion (20-30 mm) of the ladle wall thickness (based on an average thickness of 125 mm). 24m 3 Casting package and 24m 3 The interfacial heat transfer coefficient of the casting ladle (insulation) is calculated based on the effective thermal conductivity formula.

[0098] Among them 24m 3 The casting ladle (insulated) employs a slow cooling and insulation process: After slag is received, the composite covering agent on the surface of the ladle is a mixture of carbonized rice husks (particle size ≤10 mm, 95%) and aluminosilicate fiber cotton (5%), possessing both reducing and heat-insulating properties. The covering thickness is controlled at 60-80 mm, forming a dense insulation layer that effectively isolates air, prevents copper slag oxidation, and reduces surface radiation and convective heat loss. Subsequently, a three-layer composite insulation cover is used to seal the ladle opening using specialized lifting equipment. The insulation cover structure, from top to bottom, consists of: an outer heat-resistant steel frame, a middle layer of insulation cotton, and a bottom layer coated with heat-reflective paint. A high-temperature resistant insulation partition is installed between the insulation cover and the ladle opening to ensure overall sealing. After the cover is closed, the slag surface area remains in a liquid phase, which is conducive to the sedimentation and aggregation of fine copper-containing droplets near the ladle opening. The sealed ladle is then transported by a crane to a high-efficiency insulation chamber for slow cooling. The insulation chamber has a split upper and lower structure. Both the main body and the automatically opening and closing top cover employ a four-layer composite design: from the inside out, the layers are: an inner steel frame, a middle layer filled with high-silica fiber cotton (200mm thick) with a density of 128 kg / m³, an inner lining of heat-resistant nanoporous insulation board, and an outer steel frame. The total volume of the insulation chamber is 6×6×4 m². 3 The overall volume is larger than that of the slag bag, with clearance reserved for hoisting, temperature measurement, and venting. The top cover is equipped with an automatic opening and closing system, supporting remote control. Inside the insulation chamber, 6-8 K-type thermocouples are arranged in a three-dimensional space to monitor temperature changes on the top, bottom, and sides of the slag bag, and transmit the data to the central control system in real time.

[0099] Simulation results show that 12m 3 The overall cooling rate of the casting ladle under air cooling conditions was generally below 0.01℃ / s, consistent with the measured value of 0.0016℃ / s; however, the cooling rate of the area in direct contact with air was significantly higher, reaching up to 0.4℃ / s. This was compared with a 12m... 3Simulation results for a casting ladle and a welded ladle of the same volume revealed that the casting ladle experienced a slower temperature drop during filling, requiring a longer solidification time (casting ladle: 172,200 s; welded ladle: 114,646 s), and had a thinner solidified shell (casting ladle: 3.57 mm; welded ladle: 37.72 mm). Here, solidification time is defined as the time required for copper smelting slag to completely solidify within the ladle. It is evident that, under the same volume conditions, the casting ladle and the welded ladle exhibit significant differences in their slow cooling processes.

[0100] During the experiment, 12m 3 Cooling curves of the ladle walls during the slow cooling process of high-temperature smelting slag were measured at a height of 1.26 m for both the foundry ladle and the welded ladle of the same volume. Data showed that the overall temperature of the outer wall of the foundry ladle was lower than that of the welded ladle. Simulation analysis further indicated that the temperature difference between the inner and outer walls of the foundry ladle was significantly greater than that of the welded ladle: when the outer wall temperature of the foundry ladle was 350℃, the inner wall temperature at the same height was 740℃, a temperature difference of 390℃; while when the outer wall temperature of the welded ladle was 400℃, the inner wall temperature was 420℃, a temperature difference of only 20℃. This result also confirms the low thermal conductivity of the foundry ladle, which results in a relatively lower outer wall temperature. Further employing a combined insulation cover and insulation chamber for slow cooling, along with a ventilation control system for the insulation chamber, maintained the temperature inside the insulation chamber below 250℃, thus ensuring that the temperature of the slag ladle body remained below 300℃, maintaining its good mechanical strength. Due to the low thermal conductivity of the foundry ladle, even at 250℃, the temperature change process inside the slag ladle was not significantly affected. This was especially true for the 24m ladle. 3 Large-capacity foundry slag ladles have thicker walls, resulting in slower heat transfer and making it easier to control the wall temperature below 300℃. This also ensures more reliable mechanical strength.

[0101] In one simulation case, a 12m² direct air-cooled system was used. 3 Foundry ladle, 12m 3 Welding package, 24m 3 Casting package, and 24m² equipped with multi-layer insulation structure 3 A simulation analysis was conducted on the casting ladle (insulated), testing the liquid phase content 8-12 hours after solidification following slag collection. The results are shown in Table 2. It can be seen that the insulation effect of the casting ladle is better than that of the welded ladle, and the large-volume casting ladle is better than the small-volume casting ladle; after slow cooling and solidification for 12 hours under insulation conditions, the proportion of high-temperature liquid phase still reaches 88.7%, as shown in Table 2. Figure 6 As shown, (it can be inferred that the liquid phase ratio should be above 90% after 8 hours of solidification). Furthermore, after 12 hours of slow cooling, a distinct solidified shell layer had formed on the walls of the small-volume slag bag, while the 24 m... 3No solidified shell layer was observed on the ladle wall after 12 hours of heat preservation and slow cooling. This indicates that the heat preservation and slow cooling technology used in this invention can indeed maintain a high-temperature liquid phase window above 1205℃ for 8-12 hours, thus providing favorable conditions for the rapid coarsening of copper particles.

[0102] Table 2. Percentage of liquid phase content after 8-12 hours of heat preservation and slow cooling of different slag bags

[0103]

[0104] In another simulation case, the formation of the solidified shell layer immediately after slag collection was compared between different slag bags under air cooling and the heat preservation and slow cooling process of the present invention. Figure 7 The simulation inputs for different slag bags are shown in Table 3. The term "instantaneous solidified shell" refers to the slag layer that solidifies within 1100 seconds after slag receiving. "Air cooling" refers to natural cooling of the slag bag body in air without the use of a covering agent, insulating cover, or insulating chamber; "slow cooling with insulation" refers to slow cooling using the method described in this invention, i.e., a combination of the slag bag, covering agent, insulating cover, and insulating chamber. The simulation results are shown in Table 3.

[0105] Table 3. Analysis of the thickness and volume of the slag bag wall and surface crust of different slag bag types within the same time period.

[0106]

[0107] Table 3 shows the results: under air-cooled conditions, 12m 3 The thickness and volume of the solidified shell layer on the wall of the welding package are approximately 12m. 3 More than 10 times the size of the casting ladle, and 12m 3 The corresponding value for the casting ladle is 24m. 3 The difference is 4-7 times that of casting ladles. Similar significant differences are also observed in the surface solidified shell layer. This indicates that casting ladles, especially large-capacity casting ladles, exhibit significantly superior heat preservation and slow cooling performance due to the reduced thermal conductivity caused by the dispersed pore structure within their walls. Furthermore, when combined with the heat preservation and slow cooling process described in this invention, the 24 m 3 The solidified shell layer (including the surface and the wall portion) of the casting ladle was completely remelted and eliminated within 1000 seconds.

[0108] The weight of copper in the solidified shell can be calculated based on the slag type, shell thickness, and copper content of different slag types. Because the copper particles in the solidified shell are small, they are difficult to recover effectively by flotation, leading to a decrease in the overall copper recovery rate. At 1000 seconds after slag collection, at a depth of 12 m... 3 The thickness of the solidified shell layer in the casting cladding is only 3.57 mm, while the thickness of the 12 m cladding shell layer is only 3.57 mm. 3 The weld bead thickness reached 37.72 mm, and the weld m was 24 m. 3The casting ladle thickness is as low as 0.543mm. This is based on the following: the smelting slag contains 1wt% copper, the converter slag contains 4wt% copper, the mixing ratio of the two is 4.5:1, and the slag density is 3.5g / cm³. 3 Based on the conditions and the estimated copper loss according to the thickness of the solidified shell, it can be seen that the solidified shell of the casting ladle is relatively thin, with a single ladle being 12m thick. 3 Compared to a welding ladle of the same volume, a casting ladle can recover approximately 39.454 kg more copper when processing smelting slag; a single ladle is 24 m³. 3 The casting ladle can recover approximately 42.534 kg more copper. If converted into tailings indicators, replacing the welding slag ladle with the casting slag ladle can reduce the copper content in the tailings from 0.25% to below 0.15%, or even below 0.12%, thereby increasing the copper recovery rate by more than 20%.

[0109] During the experiment, a simulation comparison of 12m was also conducted. 3 Casting ladle and 24m 3 The thickness of the solidified shell at different times after the slag collection in the casting ladle is shown in Table 4.

[0110] Table 4 12m 3 Casting ladle and 24m 3 Thickness of solidified shell layer on the ladle wall at different times

[0111]

[0112] Under normal temperature and slow cooling conditions (i.e., air cooling without additional insulation), it can be observed that: 26 seconds after the slag collection is completed, 12 m 3 With 24 m 3 The solidified shell thickness of both casting ladles was 0 mm; at 105 seconds, the temperature of both slag ladles was still above the liquidus and had not yet begun to solidify, with the solidified shell thickness remaining at 0 mm; at 236 seconds, the casting ladles began to form a solidified shell, but the amount of solidified shell was very small, with 24 m... 3 The thickness of the solidified shell of the slag bag is less than 12 m. 3 Slag ladle; at 315 seconds, the solidified shell of the casting ladle begins to thicken slowly, at which point 24 m... 3 The thickness of the solidified shell of the slag bag is approximately 12 m. 3 Half of the slag bag; at 498 seconds, 12 m 3 The solidified shell layer of the casting ladle is more than 24 m thick. 3 Casting ladle; at the 1000th second, 12 m 3 The thickness of the solidified shell layer in the casting ladle remained at a low level (approximately 3.57 mm), while the 24 m 3 The casting ladle was even thinner (0.543 mm); the difference in the thickness of the solidified shell between the two types of casting ladles remained significant until 1758 seconds.

[0113] The 24 m... prepared using the specific casting process of this invention 3 The casting ladle has a diffusely distributed porous structure on its walls. Observations of the solidified shell thickness under slow cooling conditions show that the solidified shell thickness remained at 0 from the completion of slag collection until 1758 seconds. This indicates that under the slow cooling process of this invention, the formation of the solidified shell can be completely suppressed, thereby effectively reducing the copper content in the tailings.

[0114] The experiment also simulated the continuous injection of high-temperature molten slag at 1200-1400℃ into a 12 m³ well. 3 Welding package, 12 m 3 The dynamic changes in the thickness of the solidified shell during slag collection in both the casting ladle and the 24 m³ casting ladle are observed. It can be observed that due to the 24 m³... 3 The casting vessel has a large volume and high heat capacity. The solidified shell layer formed on the vessel wall in the early stage of slag receiving will be gradually remelted by the continuous scouring and heat conduction of the high-temperature molten slag, and will eventually disappear completely when the slag vessel is filled to 80% capacity.

[0115] This invention, through simulation and comparison of slag ladles of different volumes and casting processes, reveals that casting ladles are more conducive to the heat preservation and slow cooling of high-temperature molten slag compared to welded ladles. Specifically, the high-temperature liquid slag cools more slowly within the casting ladle, and the segregation rate of copper particles in the liquid melt is higher than its solidification rate, thereby increasing the particle size of copper particles in the solidified slag and significantly reducing the copper content in the tailings. Further research shows that when the casting slag ladle volume is sufficiently large and a casting slag ladle with the specific pore distribution structure described in this invention is used, the solidified shell layer originally formed on the inner wall of the slag ladle can be completely remelted and eliminated; while under the same volume conditions, the instantaneous solidified shell layer of a welded ladle is significantly thicker (more than 10 times thicker).

[0116] In another embodiment, a 12 m³ copper plant was used by a copper company. 3 Foundry slag bag and 12 m 3 Samples were taken from the solidified slag at the ladle wall after the welding slag ladle solidified. A significant difference in the thickness of the solidified shell between the casting ladle and the welding ladle was observed. Figure 8As shown in the figure, the distribution of the copper phase was analyzed by XRF. The results showed that there were significant differences in the copper phase content distribution in the direction away from the ladle wall between the two types of slag ladles: the copper phase distribution was more concentrated near the ladle wall in the welded ladle, while the copper content in the casting ladle was very low in the region near the ladle wall. The copper phase that can be recovered by flotation in copper smelting slag is mainly matte particles. It is known that the solidification line of copper slag is about 1057℃, while the solidification line of matte is between 940-1000℃. Combining the analysis of the instantaneously solidified shell layer in Table 3 and the XRF results, it can be inferred that the preferentially solidified slag phase will push matte into the liquid phase, thereby causing matte segregation, and the degree of segregation is positively correlated with temperature. The higher the temperature, the more favorable it is for matte segregation. Since the casting ladle has a lower thermal conductivity and better heat preservation effect, it is more conducive to the segregation process. Therefore, this invention, through a special casting process, forms a diffusely distributed fine pore structure within the slag shell, which significantly improves the growth and aggregation of copper particles, effectively thins or even completely remelts the instantaneous solidified shell, and simultaneously increases the size of the copper particles. These changes directly improve the copper recovery rate in subsequent flotation processes, generating considerable economic benefits.

[0117] Therefore, in the preferred embodiment of the copper smelting slag treatment method based on heat preservation and slow cooling technology proposed in this invention, a large-capacity foundry slag ladle is recommended for slag collection, preferably 18-30m. 3 20-30m is preferred. 3 Large-capacity foundry slag ladles, such as the optimized 24m ladles used in some embodiments. 3 A large-capacity slag ladle is transported via an electric railcar to the area below the slag outlet of the copper smelting furnace to receive high-temperature molten copper smelting slag (approximately 1200-1400℃). This is compared to the traditional 12m ladle... 3 Small slag pack, using 24m 3 Large slag ladles have a large heat capacity, a lower specific surface area (A / V), and a slow thermal conductivity, which significantly slows down the overall heat dissipation process. This causes the solidified crust formed during slag receiving to remelt, effectively inhibiting the formation of a solidified crust on the inner wall of the slag ladle in the early stages of slag receiving. The extended high-temperature maintenance time reduces the solid-liquid ratio of copper smelting slag and prolongs the liquid state time with good high-temperature fluidity, providing sufficient time for the migration, sedimentation, and aggregation of small copper-containing particles on the ladle wall and at the ladle opening.

[0118] Controlled cooling of the slag bale outer wall: After the copper-containing particles have settled and grown, low-temperature nitrogen (N2) is introduced through a pre-set gas circulation channel in the insulation chamber to cool the metal structure of the slag bale outer wall and trunnions. This process controls the cooling rate to avoid thermal stress concentration, ensure the structural safety of the slag bale, restore its mechanical strength and recyclability, and extend its service life. In a preferred embodiment, within one hour after the end of the heat preservation and slow cooling process and before air quenching, an adaptive temperature control device is used to controllably cool the slag bale outer wall and trunnions with air as the cooling medium, reducing the outer surface temperature of the slag bale to ≤250℃ and restoring its mechanical strength. The adaptive temperature control device automatically adjusts the airflow in real time based on the temperature monitoring in the insulation chamber to achieve controlled cooling of the slag bale outer wall and trunnions.

[0119] Lifting to the mobile tilting platform: After the outer wall of the slag bag has cooled to the required standard, a lifting device is used to lift the slag bag to the mobile tilting platform. This platform has a hydraulic tilting control function, which can precisely adjust the tilting angle and flow rate to ensure that the liquid slag is poured out smoothly and in a controllable manner.

[0120] In some embodiments, after the heat preservation and slow cooling are completed, the top cover of the heat preservation chamber is opened, the slag bag is lifted out and transferred to the air quenching heat collection chamber. The high-temperature molten slag (temperature of about 1200°C) is introduced into the nozzle area of ​​the air quenching heat collection chamber through a high-temperature resistant chute at a stable flow rate of 2 tons / minute by moving the tilting platform.

[0121] Liquid slag air-quenching granulation and waste heat recovery: Liquid slag is poured into the air-quenching heat collection chamber, and the molten slag is guided to the air-quenching port through a high-temperature resistant chute. High-pressure gas nozzles are installed below the chute (in some embodiments, the gas pressure is controlled at 0.6-1.0 MPa; nitrogen from the oxygen production station of a copper smelter can be used as the air-quenching medium, with a nitrogen purity ≥95%; compressed air can also be used as the air-quenching medium) to break the molten slag into fine droplets and rapidly cool and solidify it, forming granulated slag with a uniform particle size (0.5-3 mm). In some embodiments, multiple rows of high-pressure gas nozzles are installed at the bottom of the air-quenching chamber, with a working pressure of 0.8 MPa and a jet velocity of over 300 m / s. The high-speed gas vertically impacts the falling molten flow from below, breaking it into fine droplets, which are then rapidly cooled and solidified within 0.5-2 seconds, forming spherical or near-spherical particles with a particle size concentrated <3 mm.

[0122] During the air quenching process, high-pressure gas and high-temperature molten slag undergo efficient heat exchange, which is achieved by controlling the gas flow rate (140-180 m³ / h). 3 The system generates 200°C flue gas per minute. This flue gas is extracted by a high-efficiency exhaust fan at the top of the heat collection chamber and sent to a drying kiln for pre-drying of copper concentrate, or for other heat recovery methods (such as copper concentrate drying, steam generation, or waste heat power generation), thus achieving cascaded utilization of energy.

[0123] In a preferred embodiment, waste nitrogen from the oxygen production station of a copper smelter is used as the high-pressure gas medium for air quenching. The nitrogen has a purity of ≥95% and contains ≤5% oxygen. This ensures that cuprous sulfide in the matte particles is not oxidized, while some ferrous oxide and ferrous sulfide are preferentially oxidized to magnetite. The magnetite can be recovered through magnetic separation, which is beneficial for separating iron resources and copper-containing particles.

[0124] The cooled granulated slag falls into the slag ditch system below, and is then conveyed by a slag ditch conveyor into the ball mill hopper. The resulting air-quenched slag particles are regular in shape, have good flowability, and are free of agglomeration, and can be directly transported to the stockpile or mineral processing system. The entire air-quenching process does not require water, completely avoiding the safety hazards such as "explosion" and steam explosion caused by traditional water cooling in the slag bale, while significantly reducing the risk of thermal stress cracking caused by rapid cooling and heating of the slag bale.

[0125] Ball milling and flotation: Since the copper-containing particles in this process have already grown sufficiently during the heat preservation and slow cooling stage (copper particle D80 > 75μm), and the overall particle size of the air-quenched granulated slag is <3mm, the copper grade distribution is more uniform and the grindability is improved. The slag then enters a ball mill for a single-stage ball milling process (target particle size: -200 mesh ≥ 80wt%). Compared to traditional processes (coarse crushing-medium crushing-fine crushing-screening-coarse grinding-fine grinding-flotation, or coarse crushing-semi-autogenous grinding-ball milling (one or two stages)-flotation), this process eliminates the three-stage crushing and screening and coarse grinding or coarse crushing + semi-autogenous grinding stages, directly performing a single-stage ball milling, significantly shortening the process flow and reducing energy consumption (saving approximately 30-40% electricity) and equipment investment.

[0126] Copper concentrate recovery by flotation: The ball-milled slurry enters the flotation system to achieve effective separation of copper minerals from gangue. Due to the increased copper particle size and high degree of liberation, the copper loss in the tailings is significantly reduced, and the flotation recovery rate is significantly improved. The grade of the obtained copper concentrate is stable at 20-25%. At the same time, after concentration and filtration, the moisture content of the concentrate and tailings can be controlled below 13%. The tailings can be used as cement admixtures, building material aggregates, etc., realizing the resource utilization of all slag.

[0127] In some embodiments, a supporting intelligent system can also be set up: Dedicated sensing equipment is deployed at key stages (the slow cooling process controls the settling and agglomeration of copper particles, and the air quenching heat collection process affects the granulation degree of copper slag) to achieve full-process data acquisition for efficient copper smelting slag treatment: Multiple thermocouples are deployed in the insulation chamber to monitor the temperature in real time, and algorithms are used to extrapolate the real-time temperature of the slag bale; temperature sensors are deployed in the ventilation system of the air quenching heat collection chamber to ensure that the automatically extracted flue gas is stably maintained at 200℃, achieving pre-drying of the copper concentrate; high-speed industrial cameras are deployed in the slag ditch system to input the collected granulated slag images into an AI image model for real-time analysis of granulation scale; simultaneously, pressure and flow sensors are installed in the nitrogen pipeline to collect air quenching nitrogen parameters. All collected data is uploaded to a database in real time via industrial Ethernet, establishing a complete data acquisition system. An intrinsic relationship model between the slow cooling rate of slag bale and the particle size distribution of granulated slag was constructed. The model was then optimized through self-iteration by combining it with the current production process to obtain key process parameters such as the optimal slow cooling time of slag bale, air quenching pressure, and flow rate. Ultimately, an intelligent system with dynamic matching and stable operation of process parameters throughout the entire process was realized, promoting the upgrading of copper smelting slag treatment towards high efficiency, intelligence, and low carbon.

[0128] In some embodiments, the copper smelting slag high-efficiency treatment system of the present invention for implementing the above-described process includes:

[0129] Large-capacity slag ladle and track-mounted electric flatcar slag receiving unit: used to collect high-temperature molten slag in front of the furnace, with a slag ladle capacity of 24m³. 3 Equipped with automatic positioning and spill prevention devices;

[0130] Composite covering agent application device and automatic composite insulation cover closing mechanism: realizes quantitative application of composite covering agent and automatic closing of insulation cover;

[0131] Intelligent temperature-controlled and insulated room: Equipped with multi-point temperature sensors and airflow circulation device to achieve precise control of the slow cooling process;

[0132] Nitrogen cooling system for the outer wall of the slag bag: Controllable cooling of the outer wall of the slag bag is achieved through pre-embedded air ducts or external nozzles;

[0133] Mobile hydraulic tipping platform: Equipped with angle feedback and speed adjustment functions to ensure smooth tipping;

[0134] Air quenching heat collection chamber: Built-in high-pressure nitrogen or compressed air nozzle array and high-temperature flue gas outlet pipe, integrating flue gas purification and waste heat recovery system;

[0135] Slag trough cooling system: The slag trough is lined with high-chromium cast iron, cast steel or ceramic, and is combined with an atomizing spray system to achieve cooling and dust suppression;

[0136] Ball mill-flotation mineral processing system: including ball mill, classifier, flotation machine and concentrate and tailings dewatering equipment;

[0137] Central intelligent dispatch and control system: integrates PLC and MES system to realize intelligent management of slag bag dispatch, temperature monitoring, energy recovery and equipment linkage.

[0138] A comparison diagram showing the copper smelting slag treatment process proposed in the preferred embodiment of the present invention with the existing process before improvement is shown below. Figure 9 This invention employs an optimized design for a large-capacity casting slag ladle, which is transported via a track-mounted electric flatcar to the area below the slag outlet of a copper smelting furnace to receive high-temperature molten copper smelting slag. Immediately after slag reception, a uniform layer of covering agent is applied to the molten slag surface, followed by a high-reflectivity composite insulation cover. The sealed large-capacity slag ladle is then hoisted into a dedicated insulation chamber for 8-12 hours of controlled-temperature slow cooling. After the copper-containing particles have settled and grown, low-temperature nitrogen (N2) is introduced through a pre-set gas circulation channel in the insulation chamber to cool the outer wall of the slag ladle and its metal structures, including the trunnions. Once the outer wall has cooled to the required level, a lifting device is used to hoist the slag ladle to a mobile tilting platform. Liquid slag is then poured into an air-quenching heat collection chamber, with the molten slag guided to the air-quenching outlet via a high-temperature resistant chute. High-pressure nitrogen nozzles are installed below the chute, utilizing the nitrogen vented from the copper smelter's oxygen production station to disperse the molten slag into fine droplets, which are then rapidly cooled and solidified to form granulated slag with a particle size (<3mm). During the air quenching process, high-pressure gas and high-temperature molten slag undergo efficient heat exchange, generating 200°C flue gas by controlling the gas flow rate. This flue gas is extracted by a high-efficiency exhaust fan at the top of the heat collection chamber and sent to a drying kiln for copper concentrate pre-drying, or for other heat recovery methods (which can be used for copper concentrate drying, steam generation, or waste heat power generation, etc.), achieving cascaded energy utilization.

[0139] Based on the above research results, this invention proposes a novel process and system for the efficient treatment of copper smelting slag based on rapid heat preservation and slow cooling technology. Specifically, it selects castings with a diffusely distributed pore structure and a smaller specific surface area (the specific surface area of ​​the slag blob is ≤3.0 m²). -1The casting slag ladle is subjected to slow cooling, resulting in a lower thermal conductivity and slower heat dissipation. This provides favorable conditions for the segregation, aggregation, and growth of copper particles in the high-temperature molten slag. Combined with a heat preservation device, the average copper particle size can reach ≥43μm after only 8-12 hours of heat preservation and slow cooling, meeting flotation requirements. Compared to conventional natural slow cooling plus in-ladle water cooling (approximately 72 hours in total), the copper particles in the smelting slag of this invention rapidly settle and aggregate under heat preservation conditions; therefore, it is called rapid heat preservation and slow cooling technology. While the copper particles grow sufficiently, over 90% of the slag remains in a liquid state, making it possible to directly air-quench and granulate the slag after slow cooling. Direct air quenching (approximately 30 minutes per bale) significantly shortens the slow cooling cycle compared to the previous 60-hour water cooling in the bale. It is precisely because of this air-quenching granulation operation that the heat from the hundreds of slag ladles, previously dispersed, can be concentrated in the air-quenching heat collection chamber, achieving heat recovery from a surface to a point. Furthermore, because air quenching can directly granulate slag particles smaller than 3mm, flotation can be performed directly after a single ball milling stage, eliminating the complex process of crushing and semi-autogenous grinding of the lumpy slag after traditional water cooling in the bale. The novel processing method and system proposed in this invention are interconnected and work synergistically to form an organic whole, achieving significant technological advancements compared to existing technologies.

[0140] The following are application examples of operations performed according to the above-described process.

[0141] Application Example 1

[0142] The slag temperature T at the smelting furnace is 1250℃; a 24 m³ foundry slag ladle is used (A / V≈0.30 m). -1 The slag surface is covered with 60 mm of carbonized rice husks and fitted with a composite insulation cover (vacuum insulation board / metal reflective coating). After the slag bag is hoisted into the insulation chamber, eight thermocouples are placed inside the chamber and near the bag wall for monitoring; during the insulation stage, the copper-containing phase settles and matures. One hour before slag discharge, the air flow is automatically adjusted in a timely manner based on the temperature monitoring inside the insulation chamber to controllably cool the outer wall and trunnions of the slag bag, reducing their temperature to ≤250℃ and restoring their mechanical strength.

[0143] A gantry crane is used to place the slag bag on a tilting platform with an inclination angle of 0-73° and the tilting rate is adjusted. The liquid slag enters the air-quenching heat collection chamber through a heat-resistant chute. A nozzle array granulates the slag using 0.8 MPa nitrogen gas at a spray angle of 30°, with a particle size analyzer showing D80 < 3mm. The heat collection flue gas is approximately 900-1000℃, and after being cooled to 250℃ by a cyclone, it enters a rotary drying kiln to dry the copper concentrate. The granulated slag falls into a wear-resistant slag trough and is conveyed by belt to the ball mill hopper, where it is ground to -200 mesh (86%) and then enters the "one rougher, two cleaners, two scavengers" flotation process. The raw ore contains 1.2% copper, the concentrate contains 23.2% copper, and the tailings contain 0.15% copper.

[0144] A large copper smelter produces 400,000 tons of crude copper annually and processes approximately 4,000 tons of slag daily. It originally used a 12m... 3 The welding slag ladle system is equipped with 400 slag ladles and 6 slag ladle cars. The copper slag undergoes natural slow cooling followed by in-ladle water cooling, with an average turnaround time of 72 hours. It requires a slow cooling area for 400 ladle positions, a stockpile, and access roads for the slag ladle cars, occupying a site area of ​​at least approximately 50,000 m². 2 After modification, the process of this invention is adopted, and a 24m³ configuration is used. 3 The facility includes 30 large casting insulation slag ladles (30 ladle positions each), 5 intelligent rail-mounted electric flatcars, 2 160-ton bridge cranes, 1 set of insulation and slow cooling system, 4 sets of tilting mechanisms, 4 sets of air quenching and granulation system, 1 waste heat recovery device, and 1 intelligent monitoring center, covering a total area of ​​2500 m². 2 .

[0145] The results of the operation show that:

[0146] The average turnaround time of slag bags is reduced to 8-12 hours, the usage of slag bags is 7.5% of the original process, there is no need for a matching slag bag slow cooling field, and the floor space is reduced to 5% of the original.

[0147] The average particle size of the copper matte particles increased from 54.98% to 73.51% with a particle size greater than 74 μm, and the copper content in the tailings decreased from 0.25% to 0.16%.

[0148] Waste heat recovery is used for copper concentrate drying, replacing steam dryers and saving 158,000 tons of steam annually.

[0149] This invention fully considers the existing overhead cranes, slag bags, site and heat source requirements of smelters. The system can be modularly modified and implemented, with significant energy saving, carbon reduction and economic benefits. It is applicable to slag treatment of various copper smelting production lines such as flash furnaces, Ausmelt / ISA blowing furnaces, and converters.

[0150] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A copper smelting slag treatment system based on rapid heat preservation and slow cooling, characterized in that, This includes foundry slag bags, insulation devices, air quenching heat collection chambers, waste heat recovery devices, and mineral processing devices; The casting slag ladle is used for receiving molten copper smelting slag at a slag discharge temperature of 1200-1400℃. The casting of the slag ladle has a diffusely distributed porous structure inside to reduce the thermal conductivity of the casting slag ladle. During the casting process of the casting slag ladle, external chills are set in the conical areas of the inner and outer walls of the slag ladle, so that the middle part of the wall thickness of the casting slag ladle has a diffusely distributed fine porous structure with a pore size of <0.1mm. The casting process of the casting slag ladle adopts an inverted pouring method, that is, the bottom is on top and the slag ladle opening is at the bottom. The heat preservation device is used to keep the molten copper smelting slag in the casting slag bag warm and cool it slowly; the heat preservation device can keep the heat preservation temperature in the casting slag bag between the slag receiving temperature and 1205℃. The air quenching heat collection chamber is used to air quench and granulate the liquid molten copper smelting slag after the heat preservation and slow cooling process is completed. The waste heat recovery device is used to recover the heat generated during the air quenching process; The mineral processing device is used to grind the copper smelting slag obtained by air quenching and granulation, and to recover copper concentrate by flotation.

2. The processing system as described in claim 1, characterized in that, The heat preservation device includes a covering agent placed inside the casting slag bag and on the surface of the molten copper smelting slag, a heat preservation cover placed at the opening of the casting slag bag, and a heat preservation chamber for holding the slag bag.

3. The processing system as described in claim 1, characterized in that, The foundry slag bag has a volume of 12-30 m³. 3 .

4. The processing system as described in claim 1, characterized in that, During the casting process of the casting slag bag, the initial solidification temperature of the casting is controlled to be 1480-1540℃.

5. A method for treating copper smelting slag using the treatment system described in any one of claims 1 to 4, characterized in that, Includes the following steps: (1) A casting slag bag is used to collect molten copper smelting slag with a slag discharge temperature of 1200-1400℃; the casting of the slag bag has a diffusely distributed pore structure inside to reduce the thermal conductivity of the casting slag bag. (2) After receiving the slag, the casting slag bag is kept warm using the heat preservation device so that the molten copper smelting slag is kept warm and cooled slowly inside the slag bag; The heat preservation temperature is between the slag receiving temperature and 1205℃, so that the copper-containing droplets continue to settle, collide and aggregate under the action of gravity, thereby achieving macroscopic segregation and coarsening of copper particles; (3) The liquid molten copper smelting slag that has been heat-insulated and slow-cooled is quenched and granulated by air to obtain solid copper smelting slag; and the heat generated during the air quenching process is recovered as waste heat. (4) After cooling the solid copper smelting slag obtained by air quenching, it is ground and then flotated to recover copper concentrate.

6. The processing method as described in claim 5, characterized in that, Before the end of the heat preservation and slow cooling in step (3) and before the air quenching, the outer wall of the slag bag and the trunnion are cooled with air as the cooling medium so that the temperature of the outer surface of the slag bag drops to ≤250℃ and its mechanical strength is restored.

7. The processing method as described in claim 5, characterized in that, Step (4) specifically involves: hoisting the cooled slag bag to a mobile hydraulic tilting platform, and by adjusting the tilting angle and speed, smoothly introducing the liquid slag into the air quenching heat collection chamber through a high-temperature resistant chute; In the air quenching heat collection chamber, a pressure of 0.6-1.0 MPa and a flow rate of 140-180 m³ / h are used. 3 A gas flow rate of / min is used to quench and granulate the liquid slag, forming granulated slag with a particle size of less than 3mm. At the same time, the high-temperature flue gas is collected and used for copper concentrate drying, steam generation, or waste heat power generation.

8. The processing method as described in claim 7, characterized in that, The gas is air or nitrogen.

9. The processing method as described in claim 5, characterized in that, The grinding process in step (4) specifically involves: directly ball milling the granular copper smelting slag obtained after air quenching to achieve a slurry fineness of -200 mesh ≥ 80wt%, followed by flotation to recover copper concentrate.

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