A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards

Abstract

The present invention provides a method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, which includes: 1) proportioning the pretreated circuit board scraps, waste automotive catalyst scraps and flux according to a certain ratio and smelting them in a smelting furnace; 2) injecting fuel and oxygen-enriched air into the smelting furnace through a top-blown lance, wherein the unit injection amount of the oxygen-enriched air is 2700-4000 m<supgt;3< / supgt> / (h·t), and the oxygen content in the oxygen-enriched air is 21%-60%; 3) after smelting is completed, discharging the crude copper rich in precious metals through the copper outlet of the smelting furnace to obtain the product. The method of the present invention adopts a unique proportioning method to change the slag type and composition of the slag. The slag has low viscosity, good fluidity, and good slag-metal separation effect, realizing high recovery rate and enrichment rate of precious metals at a relatively low temperature (1250-1350 °C), ensuring that precious metals are efficiently captured by the copper liquid, and achieving a precious metal recovery rate exceeding 95%.

Description

Technical Field

[0001] The present invention relates to a method for the collaborative resource utilization of waste circuit boards and waste automotive catalysts, which is an environmentally friendly and efficient method for comprehensively recycling circuit boards and waste automotive exhaust catalysts. It belongs to the fields of industrial waste treatment and resource utilization in the technical field of environmental protection. Background Art

[0002] With the rapid development of society, the problems of environmental and resource shortages have become increasingly prominent, and the recycling of waste resources has become an important way to promote the construction of ecological civilization. Under the background of a low-carbon society, promoting the collaborative resource utilization of various waste materials is the only way to solve the problems of resource and energy shortages.

[0003] Precious metals are widely used in industrial fields such as electronics, automobiles, and petrochemicals due to their excellent electrical conductivity and high catalytic activity. Among them, automotive exhaust purification and electronics are the largest consumption fields of precious metals, accounting for about 80% of the industrial consumption of precious metals. A large number of waste automotive catalysts and waste circuit boards generated are the most important secondary resources rich in precious metals. Efficiently recovering precious metals from waste automotive catalysts and waste circuit boards is of great significance for the safe supply of precious metal resources in China and the realization of sustainable development.

[0004] The main structure of waste automotive catalysts generally consists of cordierite carriers (5SiO 2 ·2Al 2 O 3 ·2MgO), alumina coatings (γ-Al 2 O 3 ), platinum group metal active components (Pt, Pd, Rh) and promoters (CeO 2 , ZrO 2) It consists of... At present, the conventional recovery methods mainly include hydrometallurgy, bioleaching and pyrometallurgy technologies. Among them, pyrometallurgy technology has the advantages of large processing capacity, high recovery rate and strong raw material adaptability. It is the mainstream method for large-scale recovery of precious metals by large enterprises at home and abroad. The pyrometallurgical recovery technology of precious metals in waste automotive catalysts is the metal trapping method. It uses metals such as lead, iron, and copper as trapping agents, which are mixed and smelted with waste catalysts and slag formers. The precious metals are trapped by the metals and separated from the slag phase, so as to achieve the purpose of precious metal enrichment. Lead trapping has simple operation and low smelting temperature, but there are problems such as low rhodium recovery rate (~70%) and serious lead dust pollution. The iron trapping method generally uses plasma high-temperature smelting to enrich precious metals. It has high smelting temperature and large energy consumption. It is easy to form extremely stable ferrosilicon alloys at high temperatures, and subsequent dissolution and purification are very difficult. The copper trapping method is to carry out reduction smelting of waste catalysts with copper or copper oxides, reducing agents and fluxes at high temperatures. The precious metals are trapped by the copper liquid. The copper trapping method has the advantages of high precious metal recovery rate, low energy consumption and environmental friendliness. It is the most advanced precious metal recovery technology from waste automotive catalysts in the world at present. However, foreign countries keep this technology strictly confidential. There is little research on the recovery of precious metals from waste automotive catalysts by the copper trapping method in China, and it is still in its infancy.

[0005] Electronic waste represented by waste circuit boards is also an important secondary resource containing precious metals. Waste circuit boards are important components of electronic waste. Generally, they contain 40% metals, 30% organic substances and 30% oxides, and the recovery value accounts for more than 70% of electronic waste. The metals in waste circuit boards are mainly copper, and also contain tin, lead, aluminum, zinc, iron, etc. and precious metals such as gold, silver, and platinum. Compared with primary resources such as natural ores, the metal grade in waste circuit boards is higher. It is a typical urban mine and has great recovery value. The large-scale pyrometallurgy technology is gradually becoming the mainstream process for the resource treatment of waste circuit boards in China. It is to carry out slag smelting of the disassembled and crushed waste circuit boards in a high-temperature metallurgical furnace, and the precious metals enter the molten crude copper and are separated from the dross formed by non-metallic substances.

[0006] The resource recovery of waste automotive catalysts and waste circuit boards in China started relatively late. At present, there are mainly problems such as small scale, high dispersion, large energy consumption and heavy environmental burden. The national "Circular Development Leadership Action" advocates to "vigorously promote the collaborative utilization of various industrial solid wastes". If waste automotive catalysts and waste circuit boards can be co-processed to recover precious metals, it will greatly save resources and energy and reduce secondary pollution. Summary of the Invention

[0007] In view of the problems existing in the resource recycling of waste automotive catalysts and waste circuit boards in China, such as small scale, high dispersion, high energy consumption, and heavy environmental burden, the present invention provides a method for synergistic smelting and enrichment of precious metals from waste automotive catalysts and waste circuit boards. Using metals such as copper in waste circuit boards as collectors, and making slag with oxides in waste automotive catalysts and waste circuit boards, precious metals in the two wastes are synergistically smelted and enriched to form a precious metal-copper alloy and separated from the slag phase, realizing the green recovery of precious metals.

[0008] A method for synergistic smelting and enrichment of precious metals from waste automotive catalysts and waste circuit boards provided by the present invention includes the following steps:

[0009] 1) Mix the pretreated waste circuit board scraps, waste automotive catalyst scraps, and flux according to FeO / SiO in the mixture 2 = 0.5 - 1.0, FeO / Al 2 O 3 = 0.8 - 1.5, MgO = 5 - 10%, CaO = 5 - 15%, Al 2 O 3 < 20% for batching, and carry out smelting in a smelting furnace;

[0010] 2) Spray fuel and oxygen-enriched air into the smelting furnace through a top-blown lance. Among them, the unit injection volume of the oxygen-enriched air is 2700 - 4000 m 3 / (h·t), and the oxygen content in the oxygen-enriched air is 21% - 60%;

[0011] 3) After smelting is completed, discharge the crude copper rich in precious metals from the copper outlet of the smelting furnace to obtain.

[0012] Further, the method also includes the step of discharging the slag to an electric furnace through the slag outlet after smelting is completed. After secondary copper sedimentation, the slag is discharged and water-quenched into water-quenched slag, and at the same time, the crude copper obtained by sedimentation in the electric furnace is discharged.

[0013] Further, the specific step of discharging the slag is to discharge the slag when the copper content in the slag ≤ 0.5% after secondary copper sedimentation.

[0014] Further, the method also includes the step of pretreating the waste circuit board, specifically: removing the solder from the waste circuit board, crushing the waste circuit board after removing the solder to obtain waste circuit board scraps, sampling and analyzing the waste circuit board scraps, and classifying and stacking them according to the test results.

[0015] Further, the method also includes the pretreatment step of crushing the waste automotive catalyst.

[0016] Further, the particle size of the circuit board scraps is 10 - 70 mm, and the particle size of the waste automotive catalyst scraps is 20 - 60 mm.

[0017] Furthermore, the flux includes one or more of limestone, quartzite and scrap iron materials.

[0018] Furthermore, the temperature of the smelting is 1250 - 1350 °C and the time is 0.5 - 3 h.

[0019] Furthermore, the fuel oil is one or more of light fuel oil, ordinary diesel oil or heavy oil, and its injection volume is 300 - 600 L / h.

[0020] The research results show that when the waste automotive catalyst is added to the smelting furnace, it first melts in the slag layer at the upper part, and the precious metal particles are dispersed in the slag layer. In order to promote the precious metals in the slag layer to enter the crude copper melt, the present invention creatively proposes to blow oxygen-enriched air into the molten pool from the top to form dispersed bubbles, accelerating the mass transfer process in the slag layer and promoting the capture of the precious metals in the slag layer by the crude copper melt. However, when the injection volume of the oxygen-enriched air is too low, the smelting temperature is low, the viscosity of the slag is high, and the stirring effect of the molten pool is insufficient; when the injection volume of the oxygen-enriched air is too high, the entrainment rate of the copper droplets in the molten slag will increase, which is not conducive to the separation of slag and copper, and ultimately leads to a decrease in the recovery rate of precious metals. Based on this, the suitable injection volume of the oxygen-enriched air in the system of the present invention is determined to be 2700 - 4000 m 3 / (h·t), where h is the time unit, hour, t is the weight unit of the material, ton, and m 3 is the injection volume unit of the oxygen-enriched air, cubic meter.

[0021] The research results show that the oxygen enrichment amount is also an important influencing factor. When the oxygen enrichment amount is too low, the smelting temperature is low, the viscosity of the slag is high, and the smelting effect is poor; when the oxygen enrichment amount is too high, the oxidation rate of copper increases, and the recovery rates of copper and precious metals decrease. Based on this, the oxygen enrichment amount of the oxygen-enriched air suitable for the system of the present invention is determined to be 21% - 60%.

[0022] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0023] 1) This patent makes full use of the complementarity of the material components of the two kinds of waste materials and the common characteristics of the pyrometallurgical recovery technology. The content of metals such as copper in the waste circuit board is high and can be used as a collector for precious metals. The carrier component in the waste automotive catalyst and oxides such as glass fiber in the waste circuit board are good slag-forming agent components. The fuel of organic substances such as plastics in the waste circuit board and the oxidation of metals such as iron and aluminum will release a large amount of heat to reduce the use of additional fuel. Therefore, only by adding an appropriate amount of flux additionally can a good precious metal enrichment effect be achieved. While saving resources to the greatest extent, the recycling of the two kinds of waste materials is completed, achieving twice the result with half the effort.

[0024] 2) According to the characteristics of raw materials, a unique batching method is adopted to change the slag type and composition of the slag. Melting is carried out under the selected specific slag. The slag has low viscosity, good fluidity, and good slag-metal separation effect, achieving high recovery rate and enrichment rate of precious metals at a relatively low temperature (1250 - 1350 °C), and the recovery rate of precious metals reaches more than 95%.

[0025] 3) Based on the top-blown bath smelting furnace (smelting), an electric furnace (settling and separation) is added to achieve a double-furnace operation mode, further improving the recovery rate of precious metals. Description of the Drawings

[0026] Figure 1 It is the process principle flow chart of the co-smelting and enrichment of precious metals from waste automotive catalysts and waste circuit boards.

[0027] The present invention will be further described in detail below. However, the following examples are merely simple examples of the present invention and do not represent or limit the scope of the protection of the present invention. The scope of protection of the present invention is subject to the claims. Specific Embodiments

[0028] To better explain the present invention and facilitate understanding of the technical solution of the present invention, the present invention will be described in detail below with reference to the drawings and through specific implementation examples. However, the present invention can be implemented in many different ways defined and covered by the claims.

[0029] In the specific embodiment, the waste circuit board powder and the waste automotive catalyst powder are uniformly mixed. Table 1 shows the chemical composition of the circuit board scraps in step 1), and Table 2 shows the chemical composition of the catalyst scraps in step 1).

[0030] Table 1 Chemical Composition of Circuit Board Scraps

[0031]

[0032] Table 2 Chemical Composition of Catalyst Scraps

[0033]

[0034] Typical but non-limiting embodiments of the present invention are as follows:

[0035] Example 1

[0036] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0037] 1) Remove the solder from the waste circuit board, crush the circuit board after removing the solder to obtain circuit board scraps with a size of 10 mm to obtain the pretreated waste circuit board scraps, and crush the waste automotive catalyst to 30 mm to obtain the pretreated catalyst scraps;

[0038] 2) Mix the pretreated waste circuit board scraps, waste automotive catalyst scraps, and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and carry out smelting in a smelting furnace;

[0039] 3) Inject fuel and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel is 300 L / h, the smelting temperature at this time is 1300 °C, and the slag viscosity is 0.64 Pa·s;

[0040] 4) After the smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 98.2%, and the recovery rates of Au, Ag, Pd, and Rh are 96.5%, 97.3%, 98.1%, and 96.7%.

[0041] Example 2

[0042] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, including:

[0043] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to 10 mm to obtain the pretreated waste circuit board scraps, and crush the waste automotive catalyst to 30 mm to obtain the pretreated catalyst scraps;

[0044] 2) Mix the pretreated waste circuit board scraps, waste automotive catalyst scraps, and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and carry out smelting in a smelting furnace;

[0045] 3) Inject fuel and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 50%, the injection volume of the fuel is 300 L / h, the smelting temperature at this time is 1350 °C, and the slag viscosity is 0.44 Pa·s;

[0046] 4) After smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 99.4%, and the recovery rates of Au, Ag, Pd, and Rh are 99.1%, 98.6%, 98.3%, and 97.7% respectively.

[0047] Example 3

[0048] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0049] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to obtain circuit board fragments with a size of 10 mm to obtain pre-treated waste circuit board fragments, and crush the waste automotive catalyst to 30 mm to obtain pre-treated catalyst fragments;

[0050] 2) Mix the pre-treated waste circuit board fragments, waste automotive catalyst fragments, and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and carry out smelting in a smelting furnace;

[0051] 3) Inject fuel and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 1 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel is 300 L / h, the smelting temperature at this time is 1300 °C, and the slag viscosity is 0.66 Pa·s;

[0052] 4) After smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 97.0%, and the recovery rates of Au, Ag, Pd, and Rh are 96.4%, 95.2%, 95.3%, and 95.8% respectively;

[0053] 5) After smelting is completed, discharge the slag to an electric furnace through the slag outlet, discharge the slag after secondary copper sedimentation, water-quench it into water-quenched slag, and at the same time discharge the crude copper obtained by sedimentation in the electric furnace and mix it with the crude copper in step 4). After measurement, in the obtained crude copper, the comprehensive total recovery rate of copper is 97.8%, and the recovery rates of Au, Ag, Pd, and Rh are 96.8%, 95.7%, 96.5%, and 96.1% respectively.

[0054] Example 4

[0055] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0056] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to obtain circuit board scraps with a size of 10 mm to get the pretreated waste circuit board scraps, and crush the waste automotive catalyst to 30 mm to get the pretreated catalyst scraps;

[0057] 2) Mix the pretreated waste circuit board scraps, waste automotive catalyst scraps and limestone according to FeO / SiO in the mixture 2 = 0.5, FeO / Al 2 O 3 = 0.8, MgO = 7.8%, CaO = 10.7%, Al 2 O 3 = 18.5% for batching and carry out smelting in a smelting furnace;

[0058] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1300 °C, and the slag viscosity is 0.81 Pa·s;

[0059] 4) After the smelting is completed, discharge the crude copper rich in precious metals from the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 97.5%, and the recovery rates of Au, Ag, Pd, and Rh are 97.1%, 96.6%, 97.5%, and 95.3%;

[0060] 5) After the smelting is completed, discharge the slag to an electric furnace through the slag notch. After the secondary sedimentation of copper, discharge the slag and water-quench it into water-quenched slag. At the same time, discharge the crude copper obtained by the sedimentation of the electric furnace and mix it with the crude copper in step 4). After measurement, in the obtained crude copper, the comprehensive total recovery rate of copper is 98.0%, and the recovery rates of Au, Ag, Pd, and Rh are 97.3%, 96.5%, 97.8%, and 96.1%.

[0061] Example 5

[0062] A method for synergistic smelting and enrichment of precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0063] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to obtain circuit board scraps with a size of 10 mm to get the pretreated waste circuit board scraps, and crush the waste automotive catalyst to 30 mm to get the pretreated catalyst scraps;

[0064] 2) Mix the pretreated waste circuit board scraps, waste automotive catalyst scraps and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3= 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and smelt in a smelting furnace;

[0065] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 2700 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1250 °C, and the slag viscosity is 0.71 Pa·s;

[0066] 4) After smelting is completed, discharge the crude copper rich in precious metals through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 96.8%, and the recovery rates of Au, Ag, Pd, and Rh are 95.3%, 95.8%, 96.1%, and 95.9%.

[0067] Example 6

[0068] A method for synergistically smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0069] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to 10 mm to obtain pre-treated waste circuit board fragments, and crush the waste automotive catalyst to 30 mm to obtain pre-treated catalyst fragments;

[0070] 2) Mix the pre-treated waste circuit board fragments, waste automotive catalyst fragments and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and smelt in a smelting furnace;

[0071] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 30%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1250 °C, and the slag viscosity is 0.93 Pa·s;

[0072] 4) After smelting is completed, discharge the crude copper rich in precious metals through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 96.3%, and the recovery rates of Au, Ag, Pd, and Rh are 95.2%, 95.6%, 96%, and 95.2%.

[0073] Example 7

[0074] A method for synergistically smelting and enriching precious metals by waste automobile catalysts and waste circuit boards, comprising:

[0075] 1) removing solder from waste circuit boards, crushing the circuit boards after the solder removal to obtain circuit board scraps of 10 mm, and obtaining pre-treated waste circuit board scraps; crushing waste automobile catalysts to 30 mm, and obtaining pre-treated catalyst scraps;

[0076] 2) The pretreated waste circuit board scraps, waste automobile catalyst scraps and limestone are mixed according to the FeO / SiO 2 =0.9,FeO / Al 2 O 3 =1.4, MgO=5.3%, CaO=10.3%, Al 2 O 3 = 16.3% for batching and smelting in a smelting furnace;

[0077] 3) Spray fuel oil and oxygen-enriched air into the smelting furnace through a top-blowing lance for 2 hours, wherein the unit injection volume of the oxygen-enriched air is 3400m 3 / (h·t), the oxygen enrichment in the oxygen-enriched air is 40%, the injection rate of the fuel oil is 300L / h, the smelting temperature is 1300°C, and the slag viscosity is 0.56Pa·s;

[0078] 4) After smelting, the crude copper rich in precious metals is discharged from the copper port of the smelting furnace. It has been determined that the comprehensive recovery rate of copper in the crude copper is 98.2%, and the recovery rates of Au, Ag, Pd and Rh are 97.1%, 96.9%, 97.2% and 96.3% respectively.

[0079] Example 8

[0080] A method for synergistically smelting and enriching precious metals by waste automobile catalysts and waste circuit boards, comprising:

[0081] 1) removing solder from waste circuit boards, crushing the circuit boards after the solder removal to obtain circuit board scraps of 10 mm, and obtaining pre-treated waste circuit board scraps; crushing waste automobile catalysts to 30 mm, and obtaining pre-treated catalyst scraps;

[0082] 2) The pre-treated waste circuit board scraps, waste automobile catalyst scraps and limestone are mixed according to the FeO / SiO 2 =0.7,FeO / Al 2 O 3 =1.2, MgO=6.9%, CaO=8.2%, Al 2 O 3Ingredients are prepared at 19.6% and smelted in a smelting furnace;

[0083] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 4000 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1350 °C, and the slag viscosity is 0.48 Pa·s;

[0084] 4) After smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 98.8%, and the recovery rates of Au, Ag, Pd, and Rh are 98.1%, 97.6%, 98.4%, and 97.2%.

[0085] Comparative Example 1

[0086] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards includes:

[0087] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to 10 mm to obtain pre-treated waste circuit board fragments, and crush the waste automotive catalyst to 30 mm to obtain pre-treated catalyst fragments;

[0088] 2) Mix the pre-treated waste circuit board fragments, pre-treated waste automotive catalyst fragments and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for ingredient preparation and smelt in a smelting furnace;

[0089] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 1500 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1200 °C, and the slag viscosity is 1.32 Pa·s;

[0090] 4) After smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 85.8%, and the recovery rates of Au, Ag, Pd, and Rh are 81.6%, 82.1%, 84.6%, and 80.3%.

[0091] Comparative Example 2

[0092] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0093] 1) Removing solder from the waste circuit board, crushing the circuit board after solder removal to obtain circuit board fragments with a size of 10 mm to obtain pre-treated waste circuit board fragments, and crushing the waste automotive catalyst to 30 mm to obtain pre-treated catalyst fragments;

[0094] 2) Mixing the pre-treated waste circuit board fragments, pre-treated catalyst fragments and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and carrying out smelting in a smelting furnace;

[0095] 3) Spraying fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 5000 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1350 °C, and the viscosity of the slag is 0.46 Pa·s;

[0096] 4) After the smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 94.8%, and the recovery rates of Au, Ag, Pd, and Rh are 88.7%, 87.3%, 89.5%, and 86.8%.

[0097] Comparative Example 3

[0098] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0099] 1) Removing solder from the waste circuit board, crushing the circuit board after solder removal to obtain circuit board fragments with a size of 10 mm to obtain pre-treated waste circuit board fragments, and crushing the waste automotive catalyst to 30 mm to obtain pre-treated catalyst fragments;

[0100] 2) Mixing the pre-treated waste circuit board fragments, pre-treated catalyst fragments and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching, and carrying out smelting in a smelting furnace;

[0101] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blowing lance and smelt for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 15%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1200 °C, and the slag viscosity is 1.58 Pa·s;

[0102] 4) After the smelting is completed, discharge the crude copper rich in precious metals through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 77.3%, and the recovery rates of Au, Ag, Pd, and Rh are 75.4%, 76.2%, 76.2%, and 74.1%.

[0103] Comparative Example 4

[0104] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0105] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to obtain circuit board fragments with a size of 10 mm to obtain pretreated waste circuit board fragments, and crush the waste automotive catalyst to 30 mm to obtain pretreated catalyst fragments;

[0106] 2) Mix the pretreated waste circuit board fragments, waste automotive catalyst fragments and limestone according to FeO / SiO in the mixture 2 = 0.7, FeO / Al 2 O 3 = 1.2, MgO = 6.9%, CaO = 8.2%, Al 2 O 3 = 19.6% for batching and smelt in a smelting furnace;

[0107] 3) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blowing lance and smelt for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 90%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1400 °C, and the slag viscosity is 0.26 Pa·s;

[0108] 4) After the smelting is completed, discharge the crude copper rich in precious metals through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 93.6%, and the recovery rates of Au, Ag, Pd, and Rh are 89.3%, 90.1%, 90.8%, and 84.5%.

[0109] Comparative Example 5

[0110] A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, comprising:

[0111] 1) Remove the solder from the waste circuit board, crush the circuit board after solder removal to obtain circuit board scraps with a size of 10 mm to obtain pre-treated waste circuit board scraps, and crush the waste automotive catalyst to 30 mm to obtain pre-treated catalyst scraps;

[0112] 2) Mix the pre-treated waste circuit board scraps, waste automotive catalyst scraps and limestone according to FeO / SiO in the mixture 2 = 0.2, FeO / Al 2 O 3 = 0.4, MgO = 9.7%, CaO = 12.4%, Al 2 O 3 = 23.6% for batching, and carry out smelting in a smelting furnace;

[0113] 3) Spray fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance for smelting for 2 h. Among them, the unit injection volume of the oxygen-enriched air is 3400 m 3 / (h·t), the oxygen content in the oxygen-enriched air is 40%, the injection volume of the fuel oil is 300 L / h, the smelting temperature at this time is 1300 °C, and the slag viscosity is 1.84 Pa·s;

[0114] 4) After the smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace. After measurement, in the obtained crude copper, the comprehensive recovery rate of copper is 72.6%, and the recovery rates of Au, Ag, Pd, and Rh are 72.3%, 74.4%, 78.5%, and 61.2%.

[0115] It should be understood that for those of ordinary skill in the art, improvements or changes can be made according to the above description, and all such improvements and changes should fall within the protection scope of the appended claims of the present invention.

Claims

1. A method for co-smelting and enriching precious metals from waste automotive catalysts and waste circuit boards, characterized in that, the method comprises the following steps: 1) Charge the pre-treated waste circuit board scraps, waste automotive catalyst scraps and flux according to the following ratios in the mixture: FeO / SiO 2 = 0.5 - 1.0, FeO / Al 2 O 3 = 0.8 - 1.5, MgO = 5 - 10%, CaO = 5 - 15%, Al 2 O 3 < 20%, and then smelt in a smelting furnace; 2) Inject fuel oil and oxygen-enriched air into the smelting furnace through a top-blown lance. Among them, the unit injection volume of the oxygen-enriched air is 2,700 - 4,000 m 3 / (h·t), and the oxygen content in the oxygen-enriched air is 30% - 60%; 3) After smelting is completed, the crude copper rich in precious metals is discharged through the copper outlet of the smelting furnace to obtain the product.

2. The method according to claim 1, characterized in that, the method further comprises, after smelting is completed, discharging the slag through the slag outlet to an electric furnace, discharging the slag after secondary copper sedimentation, water quenching it into water quenched slag, and at the same time discharging the crude copper obtained by sedimentation in the electric furnace.

3. The method according to claim 2, characterized in that, the discharging of the slag specifically means discharging the slag when the copper content in the slag ≤ 0.5% after secondary copper sedimentation.

4. The method according to any one of claims 1-3, characterized in that, the method further comprises a step of pretreating the waste circuit board, specifically: removing the solder from the waste circuit board, crushing the waste circuit board after solder removal to obtain waste circuit board fragments, sampling and chemically analyzing the waste circuit board fragments, and classifying and stacking them according to the chemical analysis results.

5. The method according to any one of claims 1-3, characterized in that, the method further comprises a pretreatment step of crushing the waste automotive catalyst.

6. The method according to any one of claims 1-3, characterized in that, the particle size of the waste circuit board fragments is 10-70 mm, and the particle size of the waste automotive catalyst fragments is 20-60 mm.

7. The method according to any one of claims 1-3, characterized in that, the flux comprises one or more of limestone, quartzite and waste iron material.

8. The method according to any one of claims 1-3, characterized in that, the temperature of the smelting is 1250-1350 °C, and the time is 0.5-3 h.

9. The method according to any one of claims 1-3, characterized in that, the fuel is one or more of light fuel, ordinary diesel or heavy oil, and its injection volume is 300-600 L / h.

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