A technique for co-processing copper-containing waste in a cement kiln

Abstract

The present application relates to the technical field of hazardous waste disposal, and in particular to a technology for cement kiln co-processing copper-containing waste; the present application uses a cement kiln to co-process copper-containing waste, mixes the copper-containing waste with straw and waste activated carbon, grinds and granulates, and then high-temperature calcines, so as to efficiently recover the metal copper in the copper-containing waste; the present application has simple process and small investment, uses industrial waste such as plastic, rubber and tire as combustion-supporting material, has low cost and high economic efficiency; the present application uses a cement kiln to co-process copper-containing waste, so that the copper-containing waste is completely reduced, recycled and harmless, and is a green and environmentally-friendly process.

Description

Technical Field

[0001] This invention relates to the field of hazardous waste disposal technology, and in particular to a technology for co-processing copper-containing waste in a cement kiln. Background Technology

[0002] Hazardous waste refers to waste possessing various forms of toxicity, corrosivity, flammability, explosiveness, reactivity, and infectivity, posing a serious threat to the ecological environment and human health. Improper handling, storage, transportation, treatment, and disposal can severely threaten human health and even regional environmental safety. With the continuous development of industrial society, environmental pollution incidents involving hazardous waste occur frequently, seriously hindering the sustainable development of society and the economy.

[0003] Sources of copper-containing waste: glass industry, electronic component and electronic material manufacturing, mainly including: copper plating waste liquid and sludge, etching solution and sludge from the circuit board industry, pickling sludge and waste liquid, etc.

[0004] Copper pyrometallurgy is a highly polluting and energy-intensive industry, producing a wide variety and large quantity of hazardous waste, which is rich in heavy metals such as lead, arsenic, cadmium, and chromium. If not handled properly or stored, it will not only waste resources but also pose potential hazards to the groundwater, surface water, soil, and ecosystems surrounding the smelting plant.

[0005] Chinese Patent CN202211388461.1 relates to the field of copper smelting recycling technology, specifically a system for converting copper slag into renewable resources. The system includes a copper slag processing unit and a high-efficiency rotary hearth furnace. The copper slag processing unit and the high-efficiency rotary hearth furnace are connected via pipelines. One input end of the high-efficiency rotary hearth furnace is connected to the output ends of a roasting slag module, a magnetic separator, and a back-extraction screen unit. This system for converting copper slag into renewable resources mixes copper slag, a chlorinating agent, and microwave-absorbing materials. Utilizing the microwave-absorbing effect of the materials and the oxidative decomposition of chlorides, iron in the copper slag remains as magnetic iron minerals in the roasting slag. Other valuable metal elements are converted into volatile roasting flue gas. An alkaline aqueous solution absorbs the polymetallic compounds in the roasting flue gas, and an agent adjusts the pH to a weakly alkaline level, causing the metal elements to precipitate as hydroxides. This effectively separates iron from other valuable metal elements in the copper slag, enabling targeted processing.

[0006] Chinese Patent CN202210928652.6 relates to the chemical industry and provides a method for the co-treatment of gold extraction tailings, copper-containing waste, and non-ferrous metal smelting waste. The method includes a bottom-blown smelting system, a bottom-blown reduction system, and a fumigation smelting system. The bottom-blown smelting-bottom-blown reduction-fumigation smelting process treats the gold extraction tailings, copper-containing waste, and non-ferrous metal smelting waste. Sulfur in the gold extraction tailings and complex gold concentrate, along with copper in the copper-containing waste and non-ferrous metal smelting waste, undergo a physicochemical reaction at high temperatures to generate copper matte. This matte, along with lead in the mixed materials, simultaneously captures precious metals, forming lead-rich slag containing copper and precious metals. The lead-rich slag is then subjected to bottom-blown reduction, electrolysis, and precious metal refining to recover valuable metals such as lead, gold, and silver. After co-treatment of the gold extraction tailings, copper-containing waste, and non-ferrous metal smelting waste, the gold content in the fumigation slag is ≤0.1g / t, and the silver content is ≤1.0g / t. This not only results in a high recovery rate of valuable metals but also transforms the raw materials from solid waste into materials that can be used to produce building materials.

[0007] Chinese Patent CN202110328946.0 discloses a hazardous waste treatment process and its treatment device, relating to the field of hazardous waste treatment technology. The hazardous waste treatment process includes the following steps: S1 Primary incineration: Incinerating copper-containing hazardous waste at 820-880℃ to generate residue and primary flue gas; S2 Secondary combustion: Passing the primary flue gas into a combustion device at 950-1000℃, the primary flue gas flowing through the combustion device for no less than 2 seconds, and the primary flue gas combustion forming secondary flue gas; the combustion device is equipped with a catalytic coating, which is mainly made from the following raw materials in parts by weight: 25-35 parts cerium-zirconium solid solution powder, 35-45 parts molecular sieve powder, 5-8 parts manganese chloride, and 1-3 parts binder.

[0008] Current technologies for treating copper-containing waste mainly employ copper sulfate processing techniques. However, no single treatment method can completely reduce the volume and render the waste harmless. Summary of the Invention

[0009] In view of the problems existing in the prior art, the present invention provides a technology for co-processing copper-containing waste in cement kilns. After mixing, grinding and granulating the copper-containing waste with straw and waste activated carbon, the copper-containing waste can be efficiently recovered after high-temperature calcination, so that the copper-containing waste can be completely reduced, recycled and rendered harmless. It is a green and environmentally friendly process.

[0010] The technical problem solved by this invention is achieved by the following technical solution.

[0011] A technology for co-processing copper-containing waste in a cement kiln, the operation steps of which are as follows:

[0012] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5-6:2-3:1-3, and grind to a particle size of 20-30um;

[0013] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50-80mm.

[0014] S3: The prepared balls are fed into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10-20cm. Industrial waste is incinerated at the top of the hot plate furnace.

[0015] S4: Then the fired material is fed into a ball mill and ground for 1-2 hours. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0016] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0017] Preferably, the industrial waste is one or more of plastics, rubber, or tires.

[0018] Preferably, the external furnace combustion temperature is 800-950℃ and the time is 3-6 hours.

[0019] Preferably, the screened material is used as cement clinker.

[0020] Preferably, the reduction denitrification method involves injecting a reducing agent into the furnace to react with nitrogen oxides (NOx). X The reaction is selective and does not use a catalyst; the reducing agent is ammonia (NH3) or urea; the urea rapidly decomposes into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 850-1100℃; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0021] Preferably, the flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at a temperature of approximately 280-420°C under the action of a catalyst to denitrify nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0022] Preferably, the catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst = (50-100):(1-7).

[0023] Preferably, the amount of catalyst used is 0.3-3.1% of the amount of ammonia used.

[0024] Preferably, the method for preparing the organovanadium metal framework co-catalyst is as follows:

[0025] S1: Weigh 38-76 parts of 4-vinyl-1,2-phthalic acid and 43-86 parts of vanadium oxysulfate, then add them to 200-400 parts of DMF, stir thoroughly for 1-5 hours, and react at 40-50℃ for 30-60 minutes.

[0026] S2: Add 3-7 parts of 2-mercaptobenzothiazole and 2-5 parts of triethylamine, and react at 70-80℃ for 60-120 minutes;

[0027] S3: The mixture was then transferred to a hydrothermal reactor and reacted at 130-150°C for 40-80 hours. DMF was removed by distillation, and the mixture was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0028] The reaction mechanism of the organovanadium metal framework cocatalyst is as follows: 4-vinyl-1,2-phthalic acid reacts with vanadium sulfate to generate vanadium organometallic precursor 1; then it undergoes a mercapto-olefin addition reaction with 2-mercaptobenzothiazole to obtain vanadium organometallic precursor 2, which is then subjected to a hydrothermal reaction to obtain the organovanadium metal framework cocatalyst.

[0029] Technical effects:

[0030] The present invention provides a technology for co-processing copper-containing waste in cement kilns, which, compared with the prior art, has the following significant advantages:

[0031] 1. The organic ligands such as benzothiazole and phthalic acid in the organovanadium metal framework cocatalyst prepared by this invention enhance the reaction activity: the organic ligands can enhance the activity of the catalyst through interaction with the metal framework, thereby increasing the rate of molybdenum trioxide denitration reaction; the organic ligands can stabilize the structure of the vanadium catalyst, preventing the catalyst from deforming or agglomerating during the reaction, thereby extending the catalyst lifetime.

[0032] 2. This invention uses a cement kiln to co-process copper-containing waste. After mixing, grinding, and granulating the copper-containing waste with straw and waste activated carbon, it can efficiently recover metallic copper from the copper-containing waste after high-temperature calcination.

[0033] 3. The process of this invention is simple, requires little investment, and uses industrial waste such as plastics, rubber, and tires as combustion aids, resulting in low cost and high economic efficiency.

[0034] 4. This invention uses a cement kiln to co-process copper-containing waste, achieving thorough reduction, resource recovery, and harmlessness of the copper-containing waste, which is a green and environmentally friendly process. Detailed Implementation

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] The calculation methods for copper recovery rate and nitrogen oxide removal rate in specific embodiments of the present invention are as follows:

[0037] 1. Copper recovery rate (%) = Wo / Wi × 100%

[0038] Where: Wi - the weight of copper in copper-containing waste;

[0039] Wo - Weight of recycled copper granules.

[0040] 2. Nitrogen oxide removal rate (%) = (Wi - Wo) / Wi × 100%

[0041] Where: Wi - the weight of nitrogen oxides in the incinerated material;

[0042] Wo - The sum of the weights of nitrogen oxides in flue gas emissions and incineration residues.

[0043] Copper-containing waste components:

[0044] Sample Name <![CDATA[SiO2]]> Zn Fe Pb Na Cu Al Ca Sn K Mg Aluminum Gray % 31.44 18.99 6.84 6.48 5.72 4.38 3.90 2.34 0.79 0.78 0.55

[0045] Example 1

[0046] A technology for co-processing copper-containing waste in a cement kiln, the operation steps of which are as follows:

[0047] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5:2:1 and grind to a particle size of 20um;

[0048] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50mm.

[0049] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0050] S4: Then the fired material is fed into a ball mill and ground for 1 hour. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0051] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0052] The industrial waste in question is plastic.

[0053] The external furnace combustion temperature is 800℃ and the time is 3 hours.

[0054] The screened material is used as cement clinker.

[0055] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and no catalyst is used; the reducing agent is ammonia; the urea is rapidly thermally decomposed into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 850°C; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0056] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at a temperature of approximately 280°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0057] The catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst = 50:1.

[0058] The catalyst used is 0.3% of the ammonia amount.

[0059] The method for preparing the organovanadium metal framework cocatalyst is as follows:

[0060] S1: Weigh 38 kg of 4-vinyl-1,2-phthalic acid and 43 kg of vanadium oxysulfate, then add them to 200 kg of DMF, stir thoroughly for 1 hour, and react at 40°C for 30 minutes.

[0061] S2: Add 3 kg of 2-mercaptobenzothiazole and 2 kg of triethylamine, and react at 70°C for 60 minutes;

[0062] S3: The mixture was then transferred to a hydrothermal reactor and reacted at 130°C for 40 hours. DMF was removed by distillation, and the mixture was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0063] Analysis and calculations show that the copper recovery rate in this case was 92.12%, and the nitrogen oxide removal rate was 99.95%.

[0064] Example 2

[0065] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0066] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5:3:2 and grind to a particle size of 20um;

[0067] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 60mm.

[0068] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 15cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0069] S4: Then the fired material is fed into a ball mill and ground for 1.5 hours. After grinding, it is passed through a 1mm sieve. The material on the sieve is copper granules.

[0070] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0071] The industrial waste in question is rubber.

[0072] The external furnace combustion temperature is 850℃ and the time is 4 hours.

[0073] The screened material is used as cement clinker.

[0074] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and no catalyst is used; the reducing agent is ammonia; the urea is rapidly thermally decomposed into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 900℃; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0075] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at approximately 320°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0076] The catalyst is molybdenum trioxide: organovanadium metal framework co-catalyst = 65:3.

[0077] The amount of catalyst used is 1% of the amount of ammonia used.

[0078] The method for preparing the organovanadium metal framework cocatalyst is as follows:

[0079] S1: Weigh 45kg of 4-vinyl-1,2-phenylenediic acid and 50kg of vanadium oxysulfate, then add them to 250kg of DMF, stir thoroughly for 2 hours, and react at 45℃ for 40 minutes.

[0080] S2: Add 4 kg of 2-mercaptobenzothiazole and 3 kg of triethylamine, and react at 75°C for 80 minutes;

[0081] S3: The mixture was then transferred to a hydrothermal reactor and reacted at 135°C for 50 hours. DMF was removed by distillation, and the mixture was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0082] Analysis and calculations show that the copper recovery rate in this case was 93.61%, and the nitrogen oxide removal rate was 99.97%.

[0083] Example 3

[0084] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0085] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 6:3:2 and grind to a particle size of 30um;

[0086] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 70mm.

[0087] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 15cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0088] S4: Then the fired material is fed into a ball mill and ground for 1.5 hours. After grinding, it is passed through a 1mm sieve. The material on the sieve is copper granules.

[0089] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0090] The industrial waste in question is rubber.

[0091] The external furnace combustion temperature is 900℃ and the time is 5 hours.

[0092] The screened material is used as cement clinker.

[0093] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and does not use a catalyst; the reducing agent is urea; the urea rapidly decomposes into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 1000℃; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0094] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at approximately 380°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0095] The catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst = 90:5.

[0096] The catalyst used is 2% of the ammonia amount.

[0097] The method for preparing the organovanadium metal framework cocatalyst is as follows:

[0098] S1: Weigh 70 kg of 4-vinyl-1,2-phenylenediic acid and 80 kg of vanadium oxysulfate, then add them to 350 kg of DMF, stir thoroughly for 4 hours, and react at 45°C for 50 minutes.

[0099] S2: Add 6 kg of 2-mercaptobenzothiazole and 4 kg of triethylamine, and react at 75°C for 100 minutes;

[0100] S3: The mixture was then transferred to a hydrothermal reactor and reacted at 145°C for 70 hours. DMF was removed by distillation, and the mixture was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0101] Analysis and calculations show that the copper recovery rate in this case is 95.63%, and the nitrogen oxide removal rate is 99.99%.

[0102] Example 4

[0103] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0104] S1: Mix copper-containing waste with straw and waste activated carbon in a 6:3:3 ratio and grind to a particle size of 30um;

[0105] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 80mm.

[0106] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 20cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0107] S4: Then the fired material is fed into a ball mill and ground for 2 hours. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0108] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0109] The industrial waste mentioned is tires.

[0110] The external furnace combustion temperature is 950℃ and the time is 6 hours.

[0111] The screened material is used as cement clinker.

[0112] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and does not use a catalyst; the reducing agent is urea; the urea rapidly decomposes into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 1100℃; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0113] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at approximately 420°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0114] The catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst = 100:7.

[0115] The catalyst dosage is 3.1% of the ammonia dosage.

[0116] The method for preparing the organovanadium metal framework cocatalyst is as follows:

[0117] S1: Weigh 76 kg of 4-vinyl-1,2-phthalic acid and 86 kg of vanadium oxysulfate, then add them to 400 kg of DMF, stir thoroughly for 5 hours, and react at 50°C for 60 minutes.

[0118] S2: Add 7 kg of 2-mercaptobenzothiazole and 5 kg of triethylamine, and react at 80 °C for 120 minutes;

[0119] S3: The mixture was then transferred to a hydrothermal reactor and reacted at 150°C for 80 hours. DMF was removed by distillation, and the mixture was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0120] Analysis and calculations show that the copper recovery rate in this case was 95.19%, and the nitrogen oxide removal rate was 99.98%.

[0121] Comparative Example 1

[0122] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0123] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5:2:1 and grind to a particle size of 20um;

[0124] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50mm.

[0125] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0126] S4: Then the fired material is fed into a ball mill and ground for 1 hour. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0127] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0128] The industrial waste in question is plastic.

[0129] The external furnace combustion temperature is 800℃ and the time is 3 hours.

[0130] The screened material is used as cement clinker.

[0131] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and no catalyst is used; the reducing agent is ammonia; the urea is rapidly thermally decomposed into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 850°C; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0132] Analysis and calculations show that the copper recovery rate in this case was 80.68%, and the nitrogen oxide removal rate was 83.67%.

[0133] Comparative Example 2

[0134] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0135] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5:2:1 and grind to a particle size of 20um;

[0136] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50mm.

[0137] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0138] S4: Then the fired material is fed into a ball mill and ground for 1 hour. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0139] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0140] The industrial waste in question is plastic.

[0141] The external furnace combustion temperature is 800℃ and the time is 3 hours.

[0142] The screened material is used as cement clinker.

[0143] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and no catalyst is used; the reducing agent is ammonia; the urea is rapidly thermally decomposed into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 850°C; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0144] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at a temperature of approximately 280°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0145] The catalyst is molybdenum trioxide.

[0146] The catalyst used is 0.3% of the ammonia amount.

[0147] Analysis and calculation show that the copper recovery rate in this case is 85.37%, and the nitrogen oxide removal rate is 88.55%.

[0148] Comparative Example 3

[0149] A technology for co-processing copper-containing waste in a cement kiln, comprising the following steps:

[0150] S1: Mix copper-containing waste with straw and waste activated carbon in a ratio of 5:2:1 and grind to a particle size of 20um;

[0151] S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50mm.

[0152] S3: The prepared balls are sent into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10cm. The industrial waste is incinerated at the top of the hot plate furnace.

[0153] S4: Then the fired material is fed into a ball mill and ground for 1 hour. After passing through a 1mm sieve, the material on the sieve is copper granules.

[0154] S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and rising flue... X Part of it is reduced and denitrified by the reducing agent to produce harmless substances.

[0155] The industrial waste in question is plastic.

[0156] The external furnace combustion temperature is 800℃ and the time is 3 hours.

[0157] The screened material is used as cement clinker.

[0158] The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and no catalyst is used; the reducing agent is ammonia; the urea is rapidly thermally decomposed into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the temperature is 850°C; the SNCR denitrification method denitrates the fully combusted flue gas in the upper part of the furnace.

[0159] The flue gas after SNCR denitrification is further denitrified by SCR denitrification; the SCR denitrification method involves injecting ammonia into the flue gas at a temperature of approximately 280°C under the action of a catalyst to remove nitrogen oxides (NOx). X It is reduced to N2 and H2O.

[0160] The catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst = 50:1.

[0161] The catalyst used is 0.3% of the ammonia amount.

[0162] The method for preparing the organovanadium metal framework cocatalyst is as follows:

[0163] S1: Weigh 38 kg of 4-vinyl-1,2-phthalic acid and 43 kg of vanadium oxysulfate, then add them to 200 kg of DMF, stir thoroughly for 1 hour, and react at 40°C for 30 minutes.

[0164] S2: It was then transferred to a hydrothermal reactor and reacted at 130°C for 40 hours. DMF was removed by distillation, and the product was washed and dried to obtain an organovanadium metal framework co-catalyst.

[0165] Analysis and calculations show that the copper recovery rate in this case was 87.72%, and the nitrogen oxide removal rate was 90.24%.

[0166] By comparing the data from the above embodiments and comparative examples, the present invention utilizes a cement kiln to co-process copper-containing waste. After mixing, grinding, and granulating the copper-containing waste with straw and waste activated carbon, it can efficiently recover metallic copper from the copper-containing waste after high-temperature calcination.

[0167] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for co-processing copper-containing waste in a cement kiln, comprising the following steps: S1: Mix copper-containing waste with straw and waste activated carbon in a mass ratio of 5-6:2-3:1-3, and grind to a particle size of 20-30μm; S2: After grinding, it is sent to a disc granulator for granulation, and the particle size is controlled at 50-80mm. S3: The prepared balls are fed into the external furnace of the cement kiln and laid at the bottom of the hot plate furnace. The thickness of the bottom material layer is controlled at 10-20cm. Industrial waste is incinerated at the top of the hot plate furnace. S4: Then the fired material is fed into a ball mill and ground for 1-2 hours. After passing through a 1mm sieve, the material on the sieve is copper granules. S5: The flue gas exiting from the kiln tail of the rotary kiln enters the smoke chamber and the rising flue. The nitrogen oxides (NOx) in the flue gas entering the smoke chamber and the rising flue... X A portion of it is reduced and denitrified by a reducing agent to produce harmless substances; The flue gas after denitrification by reduction denitrification is further denitrified by SCR denitrification. The SCR denitrification method involves injecting ammonia gas into flue gas at a temperature of 280-420℃ under the action of a catalyst to denitrify nitrogen oxides (NOx). X Reduced to N2 and H2O; The catalyst is molybdenum trioxide:organovanadium metal framework co-catalyst in a mass ratio of (50-100):(1-7); The method for preparing the organovanadium metal framework cocatalyst is as follows: S1: Weigh 38-76 parts of 4-vinyl-1,2-phthalic acid and 43-86 parts of vanadium oxysulfate, then add them to 200-400 parts of DMF, stir thoroughly for 1-5 hours, and react at a set temperature of 40-50℃ for 30-60 minutes. S2: Add 3-7 parts of 2-mercaptobenzothiazole and 2-5 parts of triethylamine, and react at a set temperature of 70-80℃ for 60-120 minutes. S3: The mixture is then transferred to a hydrothermal reactor and reacted at a set temperature of 130-150℃ for 40-80 hours. DMF is removed by distillation, followed by washing and drying to obtain an organovanadium metal framework co-catalyst.

2. The method for co-processing copper-containing waste in a cement kiln according to claim 1, characterized in that: The industrial waste mentioned is one or more of plastics, rubber, or tires.

3. The method for co-processing copper-containing waste in a cement kiln according to claim 1, characterized in that: The external furnace combustion temperature is 800-950℃, and the time is 3-6 hours.

4. The method for co-processing copper-containing waste in a cement kiln according to claim 1, characterized in that: The undersize material from step S4 is used as cement clinker.

5. The method for co-processing copper-containing waste in a cement kiln according to claim 1, characterized in that: The reduction denitrification method involves injecting a reducing agent into a furnace to react with nitrogen oxides (NOx). X The reaction is selective and does not use a catalyst; the reducing agent is ammonia (NH3) or urea; the urea rapidly decomposes into ammonia (NH3) in the pyrolysis furnace, which then reacts with nitrogen oxides (NO) in the flue gas. X The reaction produces nitrogen (N2) and water; the reduction denitrification method described above denitrates the fully combusted flue gas in the upper part of the furnace.

6. The method for co-processing copper-containing waste in a cement kiln according to claim 1, characterized in that: The amount of catalyst used is 0.3-3.1% of the amount of ammonia used.