System and method for co-purification and resource recovery of continuous blowing air-quenching slag flue gas

Abstract

The present application relates to metallurgical flue gas treatment and resource recycling technical field, specifically relates to a kind of continuous blowing wind quenching slag flue gas purification and resource recycling system and recovery method, including the following steps: intelligent monitoring control unit sensor real-time acquisition flue gas flow, temperature, smoke concentration, SO2 concentration and heavy metal concentration parameter;Pretreated flue gas enters waste heat recovery unit, and heat exchange is carried out with the scrubbing liquid of spray washing module;Flue gas is sprayed, and heavy metal adsorption, high-efficiency demisting is discharged into atmosphere;Spray washing after containing slag circulating water enters self-cleaning circulating water system, and smoke dust particle is settled to conical slag hopper, and the precipitated slag discharged by conical slag hopper is acid-dissolved and recovered.The present application captures flue gas parameter and circulating water state change in real time, dynamically adjusts the spray pressure of spray washing module, liquid-gas ratio, alkali make-up amount and induced draft fan speed, to ensure that efficient dust removal, desulfurization and heavy metal adsorption effect can still be achieved under the condition of fluctuation.

Description

Technical Field

[0001] This invention relates to the field of metallurgical flue gas treatment and resource recovery technology, specifically to a system and method for the synergistic purification and resource recovery of continuous blowing slag quenching flue gas. Background Technology

[0002] Continuous blowing is a key process in modern copper, nickel, and other non-ferrous metal smelting. During this process, the air quenching of high-temperature slag generates complex flue gas containing large amounts of dust, sulfur dioxide, and heavy metal pollutants such as lead, zinc, and arsenic. Direct emission of this flue gas without effective treatment will not only cause serious environmental pollution but also lead to the loss of valuable metal resources such as copper contained in the dust. Therefore, developing efficient and economical flue gas purification and resource recovery technologies is crucial for the sustainable development of the metallurgical industry.

[0003] Currently, there are related technological explorations in the industry for the treatment of copper smelting slag flue gas. Chinese patent CN111020207B discloses a treatment device for copper smelting slag. The solution mentions that the flue gas is treated by a waste heat recovery boiler and a dust collector to recover lead-zinc-containing dust, indicating that the existing technology has recognized the recovery value of valuable metals in the dust, but there are still many shortcomings that need to be addressed.

[0004] Specifically, the core shortcomings of existing technologies are concentrated in the following aspects: First, poor adaptability to fluctuations in operating conditions. During continuous blowing, parameters such as flue gas flow rate and pollutant concentration are prone to rapid fluctuations. However, key operating parameters of existing treatment systems, such as spray volume, liquid-to-gas ratio, and induced draft volume, are mostly fixed and cannot be dynamically adjusted according to real-time operating conditions. This leads to unstable purification efficiency and makes it difficult to ensure continuous and stable emission compliance under fluctuating operating conditions. Second, insufficient capacity for multi-pollutant synergistic treatment. Existing solutions only focus on the initial collection of flue gas dust and lack a design for the synergistic and efficient removal of multiple pollutants such as sulfur dioxide and aerosol heavy metals in flue gas. A single purification target is difficult to meet current stringent environmental protection requirements and poses a risk of secondary pollution. Third, low degree of automation and high maintenance costs. In existing systems using wet washing, the sediment in the circulating water tank usually requires regular manual cleaning, which is not only labor-intensive but also prone to generating dust pollution during the cleaning process and causing the loss of valuable metals. Fourth, low energy and resource utilization rate. The flue gas from air-quenched slag contains a certain amount of medium- and low-temperature waste heat. Existing technologies do not effectively recover this part of the energy, resulting in energy waste. At the same time, the recovered dust or precipitated slag is mostly returned to the front-end process as copper-containing materials, and the economic benefits are not maximized. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a system and method for the synergistic purification and resource recovery of flue gas from continuous blowing slag quenching.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A continuous blowing slag quenching flue gas co-purification and resource recovery system includes a flue gas pretreatment unit, an intelligent monitoring and control unit, a multi-pollutant co-purification unit, a self-cleaning circulating water system, a waste heat recovery unit, and a valuable metal separation unit.

[0008] The flue gas pretreatment unit is used to collect the air-quenched slag flue gas generated by the continuous blowing process and to perform preliminary cooling and flow equalization treatment.

[0009] The intelligent monitoring and control unit includes multiple sensors installed at the outlet of the flue gas pretreatment unit, the inlet and outlet of the multi-pollutant synergistic purification unit, and the circulating water circuit, as well as a PLC controller connected to the sensors. The sensors are used to collect flue gas flow rate, temperature, dust concentration, SO2 concentration, heavy metal concentration, and circulating water pH value and turbidity parameters in real time.

[0010] The multi-pollutant synergistic purification unit includes a spray washing module, a heavy metal adsorption module, and a demisting module connected in sequence. The spray washing module is connected to a PLC controller and adjusts the spray pressure, liquid-gas ratio, and alkali replenishment amount according to the parameters monitored by the intelligent monitoring and control unit.

[0011] The self-cleaning circulating water system includes a cyclone sedimentation tank, an automatic slag discharge mechanism, a filter assembly, and a circulating water pump. The cyclone sedimentation tank is equipped with a cyclone generator and a conical slag hopper. The automatic slag discharge mechanism is connected to a PLC controller and automatically starts slag discharge according to the turbidity of the circulating water.

[0012] The waste heat recovery unit is located between the flue gas pretreatment unit and the multi-pollutant synergistic purification unit, and uses the waste heat of the flue gas to preheat the washing liquid of the spray washing module.

[0013] The valuable metal separation unit includes an acidification and dissolution tank, an extraction tank, and an electrolytic recovery device connected in sequence, used for the graded recovery of copper and other valuable metals from the precipitate discharged from the self-cleaning circulating water system.

[0014] Furthermore, the sensors of the intelligent monitoring and control unit include a flue gas flow sensor, a temperature sensor, an online dust concentration monitor, an SO2 concentration sensor, a heavy metal concentration sensor, an online circulating water pH monitor, and a turbidity sensor.

[0015] Furthermore, the spray washing module includes a variable frequency spray pump and an alkali metering pump, the demisting module includes a variable frequency induced draft fan, the variable frequency controller of the induced draft fan is connected to the signal, and the PLC controller is connected to the variable frequency spray pump, the alkali metering pump and the variable frequency induced draft fan.

[0016] Furthermore, the spray washing module adopts a double-layer spray structure, with a low-pressure wide-angle nozzle on the upper layer and a high-pressure fine mist nozzle on the lower layer. The spraying directions of the two nozzles are opposite, and the spraying pressure is 0.3-1.2MPa.

[0017] Furthermore, the heavy metal adsorption module is filled with a modified activated carbon-zeolite composite adsorbent, wherein the composite adsorbent has a particle size of 3-8 mm and a specific surface area ≥800 m². 2 / g.

[0018] Furthermore, the self-cleaning circulating water system has a guide plate inside the cyclone sedimentation tank and a pneumatic slag discharge valve at the bottom of the conical slag hopper.

[0019] This invention also includes the following technical solutions:

[0020] A method for the synergistic purification and resource recovery of continuous blowing slag quenching flue gas based on the above system includes the following steps:

[0021] S1. Flue gas pretreatment and parameter monitoring: The flue gas from continuous blowing slag quenching enters the flue gas pretreatment unit through the flue gas collection channel for preliminary cooling and flow equalization. The sensors of the intelligent monitoring and control unit collect flue gas flow rate, temperature, dust concentration, SO2 concentration and heavy metal concentration parameters in real time and transmit the data to the PLC controller.

[0022] S2. Waste heat recovery: The pretreated flue gas enters the waste heat recovery unit and exchanges heat with the washing liquid of the spray washing module. The flue gas temperature drops to 60-70℃, and the washing liquid is preheated to 40-60℃.

[0023] S3, Synergistic purification of multiple pollutants:

[0024] S3.1 Spray washing: The preheated washing liquid is sprayed in reverse through the double-layer nozzles of the spray washing module. The PLC controller adjusts the spray pressure, liquid-to-gas ratio and the replenishment amount of the alkali metering pump according to the parameters collected in S1 to maintain the pH value of the circulating water at 8.5-10.5.

[0025] S3.2 Heavy metal adsorption: The flue gas after spray washing enters the heavy metal adsorption module, where the modified activated carbon-zeolite composite adsorbent adsorbs the residual heavy metals in the flue gas.

[0026] S3.3 High-efficiency demisting: The adsorbed flue gas passes through the demisting module to remove mist droplets, and is then discharged into the atmosphere by the induced draft fan;

[0027] S4. Self-cleaning circulating water separation: The slag-containing circulating water after spray washing enters the cyclone sedimentation tank of the self-cleaning circulating water system. Under the action of cyclone centrifugal force, the dust particles settle into the conical slag hopper. When the turbidity of the circulating water is ≥50NTU, the PLC controller automatically starts the pneumatic slag discharge valve. The slag discharge cycle is 5-30 minutes, and the single slag discharge time is 1-3 minutes. The supernatant is filtered by the filter component and then returned to the spray washing module for recycling.

[0028] S5. Valuable Metal Recovery: The precipitate discharged from the conical slag hopper is sent to the acidification and dissolution tank, where sulfuric acid is added to adjust the pH value to 2.0-3.0, so that copper and other valuable metals can be dissolved. The solution enters the extraction tank for copper extraction and separation. The copper-loaded organic phase after extraction is back-extracted and sent to the electrolytic recovery unit to obtain high-purity cathode copper. The raffinate is further processed to recover other valuable metals.

[0029] Furthermore, in step S3.1, the spraying pressure is 0.3-1.2 MPa, and the liquid-to-gas ratio is 5-12 L / m³. 3 .

[0030] Furthermore, in step S5, the acidification and dissolution temperature of the precipitate is 60-80℃, the stirring rate is 150-200r / min, the copper extraction rate is ≥98%, and the purity of the cathode copper obtained by electrolytic recovery is ≥99.99%.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] This invention provides a system and method for the synergistic purification and resource recovery of flue gas from continuous blowing slag quenching. Through the organic integration and coordinated design of a flue gas pretreatment unit, an intelligent monitoring and control unit, a multi-pollutant synergistic purification unit, a self-cleaning circulating water system, a waste heat recovery unit, and a valuable metal separation unit, the entire process of continuous blowing slag quenching flue gas treatment is optimized. This is achieved by utilizing various sensors and PLCs distributed at key nodes. The controller works in synergy to capture real-time changes in flue gas parameters and circulating water status, dynamically adjusting the spray pressure, liquid-to-gas ratio, alkali replenishment amount, and induced draft fan speed of the spray scrubbing module. This ensures stable and efficient dust removal, desulfurization, and heavy metal adsorption even under fluctuating operating conditions. Through the centrifugal settling action of the cyclone sedimentation tank and the automatic control of the pneumatic slag discharge valve, slag separation and discharge can be completed without manual intervention, reducing labor intensity and avoiding resource loss and secondary pollution during the slag removal process. The waste heat recovery unit converts flue gas waste heat into preheating energy for the scrubbing liquid, significantly improving energy utilization efficiency and reducing system energy consumption. Through a combination of acidification dissolution, extraction separation, and electrolytic recovery processes, precise graded recovery of copper and other valuable metals is achieved, with a copper extraction rate of no less than 98% and cathode copper purity exceeding 99.99%, significantly enhancing the comprehensive utilization value and economic benefits of resources. Attached Figure Description

[0033] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0034] Figure 1 A schematic diagram of the system of the present invention is shown;

[0035] Figure 2 A flowchart of the method of the present invention is shown. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0037] Reference Appendix Figure 1 A continuous blowing slag quenching flue gas synergistic purification and resource recovery system includes a flue gas pretreatment unit, an intelligent monitoring and control unit, a multi-pollutant synergistic purification unit, a self-cleaning circulating water system, a waste heat recovery unit and a valuable metal separation unit.

[0038] The flue gas pretreatment unit is used to collect the air-quenched slag flue gas generated by the continuous blowing process and to perform preliminary cooling and flow equalization treatment.

[0039] The intelligent monitoring and control unit includes multiple sensors installed at the outlet of the flue gas pretreatment unit, the inlet and outlet of the multi-pollutant synergistic purification unit, and the circulating water circuit, as well as a PLC controller connected to the sensors. The sensors are used to collect flue gas flow rate, temperature, dust concentration, SO2 concentration, heavy metal concentration, and circulating water pH value and turbidity parameters in real time.

[0040] The multi-pollutant synergistic purification unit includes a spray washing module, a heavy metal adsorption module, and a demisting module connected in sequence. The spray washing module is connected to a PLC controller and adjusts the spray pressure, liquid-gas ratio, and alkali replenishment amount according to the parameters monitored by the intelligent monitoring and control unit.

[0041] The self-cleaning circulating water system includes a cyclone sedimentation tank, an automatic slag discharge mechanism, a filter assembly, and a circulating water pump. The cyclone sedimentation tank is equipped with a cyclone generator and a conical slag hopper. The automatic slag discharge mechanism is connected to a PLC controller and automatically starts slag discharge according to the turbidity of the circulating water.

[0042] The waste heat recovery unit is located between the flue gas pretreatment unit and the multi-pollutant synergistic purification unit, and uses the waste heat of the flue gas to preheat the washing liquid of the spray washing module.

[0043] The valuable metal separation unit includes an acidification and dissolution tank, an extraction tank, and an electrolytic recovery device connected in sequence, used for the graded recovery of copper and other valuable metals from the precipitate discharged from the self-cleaning circulating water system.

[0044] In one embodiment of the present invention, the sensors of the intelligent monitoring and control unit include a flue gas flow sensor, a temperature sensor, an online dust concentration monitor, an SO2 concentration sensor, a heavy metal concentration sensor, an online circulating water pH monitor, and a turbidity sensor.

[0045] In one embodiment of the present invention, the spray washing module includes a variable frequency spray pump and an alkaline solution metering pump, the demisting module includes a variable frequency induced draft fan, the induced draft fan is connected to a variable frequency controller, and the PLC controller is connected to the variable frequency spray pump, the alkaline solution metering pump and the variable frequency induced draft fan.

[0046] In one embodiment of the present invention, the spray washing module adopts a double-layer spray structure, with the upper layer being a low-pressure wide-angle nozzle and the lower layer being a high-pressure fine mist nozzle. The spraying directions of the two nozzles are opposite, and the spraying pressure is 0.3-1.2 MPa.

[0047] In one embodiment of the present invention, the heavy metal adsorption module is filled with a modified activated carbon-zeolite composite adsorbent, wherein the composite adsorbent has a particle size of 3-8 mm and a specific surface area ≥800 m². 2 / g.

[0048] In one embodiment of the present invention, the cyclone sedimentation tank of the self-cleaning circulating water system is provided with a guide plate, and the bottom of the conical slag hopper is provided with a pneumatic slag discharge valve.

[0049] Reference Appendix Figure 2 A method for synergistic purification and resource recovery of continuous blowing slag quenching flue gas based on the above system includes the following steps:

[0050] S1. Flue gas pretreatment and parameter monitoring: The flue gas from continuous blowing slag quenching enters the flue gas pretreatment unit through the flue gas collection channel for preliminary cooling and flow equalization. The sensors of the intelligent monitoring and control unit collect flue gas flow rate, temperature, dust concentration, SO2 concentration and heavy metal concentration parameters in real time and transmit the data to the PLC controller.

[0051] S2. Waste heat recovery: The pretreated flue gas enters the waste heat recovery unit and exchanges heat with the washing liquid of the spray washing module. The flue gas temperature drops to 60-70℃, and the washing liquid is preheated to 40-60℃.

[0052] S3, Synergistic purification of multiple pollutants:

[0053] S3.1 Spray washing: The preheated washing liquid is sprayed in reverse through the double-layer nozzles of the spray washing module. The PLC controller adjusts the spray pressure, liquid-to-gas ratio and the replenishment amount of the alkali metering pump according to the parameters collected in S1 to maintain the pH value of the circulating water at 8.5-10.5.

[0054] S3.2 Heavy metal adsorption: The flue gas after spray washing enters the heavy metal adsorption module, where the modified activated carbon-zeolite composite adsorbent adsorbs the residual heavy metals in the flue gas.

[0055] S3.3 High-efficiency demisting: The adsorbed flue gas passes through the demisting module to remove mist droplets, and is then discharged into the atmosphere by the induced draft fan;

[0056] S4. Self-cleaning circulating water separation: The slag-containing circulating water after spray washing enters the cyclone sedimentation tank of the self-cleaning circulating water system. Under the action of cyclone centrifugal force, the dust particles settle into the conical slag hopper. When the turbidity of the circulating water is ≥50NTU, the PLC controller automatically starts the pneumatic slag discharge valve. The slag discharge cycle is 5-30 minutes, and the single slag discharge time is 1-3 minutes. The supernatant is filtered by the filter component and then returned to the spray washing module for recycling.

[0057] S5. Valuable Metal Recovery: The precipitate discharged from the conical slag hopper is sent to the acidification and dissolution tank, where sulfuric acid is added to adjust the pH value to 2.0-3.0, so that copper and other valuable metals can be dissolved. The solution enters the extraction tank for copper extraction and separation. The copper-loaded organic phase after extraction is back-extracted and sent to the electrolytic recovery unit to obtain high-purity cathode copper. The raffinate is further processed to recover other valuable metals.

[0058] In one embodiment of the present invention, in step S3.1, the spraying pressure is 0.3-1.2 MPa and the liquid-to-gas ratio is 5-12 L / m³. 3 .

[0059] In one embodiment of the present invention, in step S5, the acidification and dissolution temperature of the precipitate is 60-80℃, the stirring rate is 150-200r / min, the copper extraction rate is ≥98%, and the purity of the cathode copper obtained by electrolytic recovery is ≥99.99%.

[0060] Example 1

[0061] This embodiment is applied to the treatment of flue gas from quenching slag in a small-scale continuous blowing refining process. The specific implementation process is as follows:

[0062] S1. Flue Gas Pretreatment and Parameter Monitoring: The flue gas from continuous blowing slag quenching enters the flue gas pretreatment unit through the flue gas acquisition channel, where it undergoes preliminary cooling and flow equalization. Sensors in the intelligent monitoring and control unit collect flue gas parameters in real time, including a flue gas flow rate of 45,000 m³ / h. 3 / h, temperature 90℃, dust concentration 800mg / m³ 3SO2 concentration 1500 mg / m³ 3 Total heavy metal concentration 50 mg / m³ 3 The sensor transmits data to the PLC controller in real time.

[0063] S2. Waste heat recovery: The pretreated flue gas enters the waste heat recovery unit and exchanges heat with the washing liquid of the spray washing module. The flue gas temperature drops to 70°C and the washing liquid is preheated to 40°C.

[0064] S3, Synergistic purification of multiple pollutants:

[0065] S3.1 Spray Washing: The washing liquid, preheated to 40℃, is sprayed in reverse through the double-layer nozzles of the spray washing module. The PLC controller adjusts the spray pressure to 0.3MPa and the liquid-to-gas ratio to 5L / m³ based on the parameters collected in S1. 3 Alkali solution is precisely replenished via an alkaline metering pump to maintain the pH value of the circulating water at 8.5, thereby achieving efficient capture of smoke and dust and initial absorption of SO2.

[0066] S3.2 Heavy metal adsorption: After being sprayed and washed, the flue gas enters the heavy metal adsorption module, where the modified activated carbon-zeolite composite adsorbent adsorbs the residual heavy metals in the flue gas.

[0067] S3.3 High-efficiency demisting: The adsorbed flue gas is demisted by the demisting module and then discharged into the atmosphere by the induced draft fan.

[0068] S4. Self-cleaning circulating water separation: The slag-containing circulating water after spray washing enters the cyclone sedimentation tank of the self-cleaning circulating water system. Under the action of centrifugal force, the dust particles settle into the conical slag hopper. When the PLC controller detects that the turbidity of the circulating water is ≥50 NTU, it automatically starts the pneumatic slag discharge valve, setting the slag discharge cycle to 5 minutes and the single slag discharge time to 1 minute. The supernatant is filtered by the filter assembly and then returned to the spray washing module for recycling.

[0069] S5. Valuable Metal Recovery: The precipitate discharged from the conical slag hopper is sent to an acidification and dissolution tank. Sulfuric acid is added to adjust the pH to 2.0, and the acidification and dissolution temperature is controlled at 60℃ with a stirring rate of 150 r / min to ensure complete dissolution of copper and other valuable metals. The solution then enters an extraction tank for copper extraction and separation. The extracted copper-loaded organic phase is back-extracted and sent to an electrolytic recovery unit to finally obtain high-purity cathode copper. Testing shows that the copper extraction rate is 98%, and the purity of the electrolytically recovered cathode copper is 99.99%. The raffinate is further treated to recover other valuable metals.

[0070] This embodiment operated for 120 days, processing a total of 5.4 million cubic meters of flue gas. 3The dust removal efficiency reached 99.0%, SO2 removal rate reached 90.0%, heavy metal removal rate reached 85.0%, and a total of 216 tons of smoke and dust and 74.3 tons of copper were recovered.

[0071] Example 2

[0072] This embodiment is applied to the treatment of flue gas from large-scale continuous blowing slag quenching. The specific implementation process is as follows:

[0073] S1. Flue Gas Pretreatment and Parameter Monitoring: The flue gas from continuous blowing slag quenching enters the flue gas pretreatment unit through the flue gas acquisition channel, where it undergoes preliminary cooling and flow equalization. Sensors in the intelligent monitoring and control unit collect flue gas parameters in real time, including a flue gas flow rate of 55,000 m³ / h. 3 / h, temperature 80℃, dust concentration 1200mg / m³ 3 SO2 concentration 3000 mg / m³ 3 Total heavy metal concentration 100 mg / m³ 3 The sensor transmits data to the PLC controller in real time.

[0074] S2. Waste heat recovery: The pretreated flue gas enters the waste heat recovery unit and exchanges heat with the washing liquid of the spray washing module. The flue gas temperature drops to 60°C, and the washing liquid is preheated to 60°C.

[0075] S3, Synergistic purification of multiple pollutants:

[0076] S3.1 Spray Washing: The washing liquid, preheated to 60℃, is sprayed in reverse through the double-layer nozzles of the spray washing module. The PLC controller adjusts the spray pressure to 1.2MPa and the liquid-to-gas ratio to 12L / m³ based on the parameters collected in S1. 3 Alkali solution is precisely replenished via an alkaline metering pump to maintain the pH value of the circulating water at 10.5, thereby enhancing the effects of dust capture and SO2 absorption.

[0077] S3.2 Heavy metal adsorption: After being sprayed and washed, the flue gas enters the heavy metal adsorption module, where the modified activated carbon-zeolite composite adsorbent deeply adsorbs the residual heavy metals in the flue gas.

[0078] S3.3 High-efficiency demisting: The adsorbed flue gas is demisted by the demisting module and then discharged into the atmosphere by the induced draft fan.

[0079] S4. Self-cleaning circulating water separation: The slag-laden circulating water after spray washing enters the cyclone sedimentation tank of the self-cleaning circulating water system. Under the action of centrifugal force, the dust particles quickly settle into the conical slag hopper. When the PLC controller detects that the turbidity of the circulating water is ≥50 NTU, it automatically starts the pneumatic slag discharge valve, setting the slag discharge cycle to 30 minutes and the single slag discharge time to 3 minutes. The supernatant is filtered by the filter assembly and then returned to the spray washing module for recycling.

[0080] S5. Valuable Metal Recovery: The precipitate discharged from the conical slag hopper is sent to an acidification and dissolution tank. Sulfuric acid is added to adjust the pH to 3.0, and the acidification and dissolution temperature is controlled at 80℃ with a stirring rate of 200 r / min to accelerate the dissolution of copper and other valuable metals. The dissolved solution enters an extraction tank for copper extraction and separation. The copper-loaded organic phase after extraction is back-extracted and sent to an electrolytic recovery unit to finally obtain high-purity cathode copper. Testing shows that the copper extraction rate is 99.5%, and the purity of the electrolytically recovered cathode copper is 99.996%. The raffinate is further treated to efficiently recover other valuable metals.

[0081] This embodiment operated for 120 days, processing a total of 6.6 million cubic meters of flue gas. 3 The dust removal efficiency reached 99.8%, SO2 removal rate reached 95.0%, heavy metal removal rate reached 92.0%, and a total of 312 tons of smoke and dust and 103.6 tons of copper were recovered.

[0082] This invention provides a system and method for the synergistic purification and resource recovery of flue gas from continuous blowing slag quenching. Through the organic integration and coordinated design of a flue gas pretreatment unit, an intelligent monitoring and control unit, a multi-pollutant synergistic purification unit, a self-cleaning circulating water system, a waste heat recovery unit, and a valuable metal separation unit, the entire process of continuous blowing slag quenching flue gas treatment is optimized. This is achieved by utilizing various sensors and PLCs distributed at key nodes. The controller works in synergy to capture real-time changes in flue gas parameters and circulating water status, dynamically adjusting the spray pressure, liquid-to-gas ratio, alkali replenishment amount, and induced draft fan speed of the spray scrubbing module. This ensures stable and efficient dust removal, desulfurization, and heavy metal adsorption even under fluctuating operating conditions. Through the centrifugal settling action of the cyclone sedimentation tank and the automatic control of the pneumatic slag discharge valve, slag separation and discharge can be completed without manual intervention, reducing labor intensity and avoiding resource loss and secondary pollution during the slag removal process. The waste heat recovery unit converts flue gas waste heat into preheating energy for the scrubbing liquid, significantly improving energy utilization efficiency and reducing system energy consumption. Through a combination of acidification dissolution, extraction separation, and electrolytic recovery processes, precise graded recovery of copper and other valuable metals is achieved, with a copper extraction rate of no less than 98% and cathode copper purity exceeding 99.99%, significantly enhancing the comprehensive utilization value and economic benefits of resources.

[0083] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A continuous blowing slag quenching flue gas co-purification and resource recovery system, characterized in that, It includes a flue gas pretreatment unit, an intelligent monitoring and control unit, a multi-pollutant synergistic purification unit, a self-cleaning circulating water system, a waste heat recovery unit, and a valuable metal separation unit; The flue gas pretreatment unit is used to collect the air-quenched slag flue gas generated by the continuous blowing process and to perform preliminary cooling and flow equalization treatment. The intelligent monitoring and control unit includes multiple sensors installed at the outlet of the flue gas pretreatment unit, the inlet and outlet of the multi-pollutant synergistic purification unit, and the circulating water circuit, as well as a PLC controller connected to the sensors. The sensors are used to collect flue gas flow rate, temperature, dust concentration, SO2 concentration, heavy metal concentration, and circulating water pH value and turbidity parameters in real time. The multi-pollutant synergistic purification unit includes a spray washing module, a heavy metal adsorption module, and a demisting module connected in sequence. The spray washing module is connected to a PLC controller and adjusts the spray pressure, liquid-gas ratio, and alkali replenishment amount according to the parameters monitored by the intelligent monitoring and control unit. The self-cleaning circulating water system includes a cyclone sedimentation tank, an automatic slag discharge mechanism, a filter assembly, and a circulating water pump. The cyclone sedimentation tank is equipped with a cyclone generator and a conical slag hopper. The automatic slag discharge mechanism is connected to a PLC controller and automatically starts slag discharge according to the turbidity of the circulating water. The waste heat recovery unit is located between the flue gas pretreatment unit and the multi-pollutant synergistic purification unit, and uses the waste heat of the flue gas to preheat the washing liquid of the spray washing module. The valuable metal separation unit includes an acidification and dissolution tank, an extraction tank, and an electrolytic recovery device connected in sequence, used for the graded recovery of copper and other valuable metals from the precipitate discharged from the self-cleaning circulating water system.

2. The continuous blowing slag quenching flue gas co-purification and resource recovery system according to claim 1, characterized in that, The sensors in the intelligent monitoring and control unit include a flue gas flow sensor, a temperature sensor, an online dust concentration monitor, an SO2 concentration sensor, a heavy metal concentration sensor, an online circulating water pH monitor, and a turbidity sensor.

3. The continuous blowing slag quenching flue gas co-purification and resource recovery system according to claim 1, characterized in that, The spray washing module includes a variable frequency spray pump and an alkaline solution metering pump. The demisting module includes a variable frequency induced draft fan. The variable frequency controller of the induced draft fan is connected to the signal. The PLC controller is connected to the variable frequency spray pump, the alkaline solution metering pump and the variable frequency induced draft fan.

4. The continuous blowing slag quenching flue gas co-purification and resource recovery system according to claim 1, characterized in that, The spray washing module adopts a double-layer spray structure, with a low-pressure wide-angle nozzle on the upper layer and a high-pressure fine mist nozzle on the lower layer. The spraying directions of the two nozzles are opposite, and the spraying pressure is 0.3-1.2MPa.

5. The continuous blowing slag quenching flue gas co-purification and resource recovery system according to claim 1, characterized in that, The heavy metal adsorption module is filled with a modified activated carbon-zeolite composite adsorbent, the composite adsorbent having a particle size of 3-8 mm and a specific surface area ≥800 m². 2 / g.

6. The continuous blowing slag quenching flue gas co-purification and resource recovery system according to claim 1, characterized in that, The self-cleaning circulating water system has a guide plate inside the cyclone sedimentation tank and a pneumatic slag discharge valve at the bottom of the conical slag hopper.

7. A method for the synergistic purification and resource recovery of continuous blowing slag quenching flue gas based on any one of the systems of claims 1-6, characterized in that, Includes the following steps: S1. Flue gas pretreatment and parameter monitoring: The flue gas from continuous blowing slag quenching enters the flue gas pretreatment unit through the flue gas collection channel for preliminary cooling and flow equalization. The sensors of the intelligent monitoring and control unit collect flue gas flow rate, temperature, dust concentration, SO2 concentration and heavy metal concentration parameters in real time and transmit the data to the PLC controller. S2. Waste heat recovery: The pretreated flue gas enters the waste heat recovery unit and exchanges heat with the washing liquid of the spray washing module. The flue gas temperature drops to 60-70℃, and the washing liquid is preheated to 40-60℃. S3. Synergistic purification of multiple pollutants: S3.1 Spray washing: The preheated washing liquid is sprayed in reverse through the double-layer nozzles of the spray washing module. The PLC controller adjusts the spray pressure, liquid-to-gas ratio and the replenishment amount of the alkali metering pump according to the parameters collected in S1 to maintain the pH value of the circulating water at 8.5-10.

5. S3.2 Heavy metal adsorption: The flue gas after spray washing enters the heavy metal adsorption module, where the modified activated carbon-zeolite composite adsorbent adsorbs the residual heavy metals in the flue gas. S3.3 High-efficiency demisting: The adsorbed flue gas passes through the demisting module to remove mist droplets, and is then discharged into the atmosphere by the induced draft fan; S4. Self-cleaning circulating water separation: The slag-containing circulating water after spray washing enters the cyclone sedimentation tank of the self-cleaning circulating water system. Under the action of cyclone centrifugal force, the dust particles settle into the conical slag hopper. When the turbidity of the circulating water is ≥50NTU, the PLC controller automatically starts the pneumatic slag discharge valve. The slag discharge cycle is 5-30 minutes, and the single slag discharge time is 1-3 minutes. The supernatant is filtered by the filter component and then returned to the spray washing module for recycling. S5. Valuable Metal Recovery: The precipitate discharged from the conical slag hopper is sent to the acidification and dissolution tank, where sulfuric acid is added to adjust the pH value to 2.0-3.0, so that copper and other valuable metals can be dissolved. The solution enters the extraction tank for copper extraction and separation. The copper-loaded organic phase after extraction is back-extracted and sent to the electrolytic recovery unit to obtain high-purity cathode copper. The raffinate is further processed to recover other valuable metals.

8. The method according to claim 7, characterized in that, In step S3.1, the spray pressure is 0.3-1.2 MPa, and the liquid-to-gas ratio is 5-12 L / m³. 3 .

9. The method according to claim 7, characterized in that, In step S5, the acidification and dissolution temperature of the precipitate is 60-80℃, the stirring rate is 150-200r / min, the copper extraction rate is ≥98%, and the purity of the cathode copper obtained by electrolytic recovery is ≥99.99%.

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