A system for synergistically treating and recycling hydrogen-containing hydrofluoric acid waste gas and waste liquid

Abstract

The present application relates to a kind of hydrogen-containing hydrofluoric acid waste gas and waste liquid synergic treatment and resource recycling system, it relates to fluorine chemical industry three waste treatment and resource recovery technical field, including collection pretreatment module, chemical deep purification module, biochemical separation module, up-to-standard discharge control module and resource intelligent control module.The hydrogen-containing hydrofluoric acid waste gas and waste liquid synergic treatment and resource recycling system, by building hydrogen-containing hydrofluoric acid waste gas and waste liquid synergic treatment and resource recycling system, realizes the integration of gas-liquid quality collection, deep purification and resource cycle.First, the system utilizes multistage precipitation and absorption process, with high efficiency to convert dissolved fluoride into solid precipitate or high concentration salt solution, and innovatively designs gas-liquid heat exchange circuit, so that the high concentration fluorine-containing mother liquor produced by waste gas absorption is reused as neutralizing agent in the fluorine removal section of wastewater, significantly reducing the consumption of lime and other reagents, while avoiding the direct discharge of high concentration salt solution, significantly improving the recovery rate and utilization rate of fluorine element.

Description

Technical Field

[0001] This invention relates to the field of fluorochemical waste treatment and resource recovery technology, specifically a system for the synergistic treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid. Background Technology

[0002] With the rapid development of industries such as fluorine chemicals, semiconductor manufacturing, and photovoltaics, the large amount of hydrofluoric acid (HF) waste gas and waste liquid generated during the production process has become an environmental problem that urgently needs to be solved. Traditional treatment methods often treat fluorine-containing waste as simple pollutants and dispose of it harmlessly. This not only causes a large waste of fluorine resources and increases the pollution control costs for enterprises, but also brings secondary solid waste treatment pressure due to the large amount of fluorine-containing sludge generated. As an important strategic resource, the high added value of fluorine determines the necessity of its resource recycling. Through efficient separation and conversion technologies, fluorides in low-concentration fluorine-containing wastewater and waste gas can be converted into high-purity fluoride salt products or reusable chemical raw materials. This can not only achieve the economic benefits of "turning waste into treasure", but also reduce the total amount of pollutants emitted from the source, which is in line with the core requirements of current green manufacturing and circular economy development.

[0003] Existing technologies for treating hydrofluoric acid-containing waste gas and liquid typically employ a separate treatment model. For waste gas, alkaline spray absorption towers are mainly used for neutralization, while for waste liquid, lime slurry precipitation is used to generate calcium fluoride sludge. In waste gas treatment, existing technologies mostly rely on single-stage or double-stage packed towers, using sodium hydroxide solution to absorb acidic gases. In wastewater treatment, lime is mainly added to adjust the pH value, causing dissolved fluoride ions to form calcium fluoride precipitate, followed by solid-liquid separation. Although some improved technologies have introduced multi-stage series absorption or chemical precipitation tanks, they often lack deep integration of gas-liquid synergistic treatment, and the treatment of by-products is relatively crude. The generated calcium fluoride sludge is usually directly landfilled as general solid waste, or only simple pressure filtration and dewatering is performed, failing to explore the recovery value of fluorine resources. This results in high energy consumption and low product utilization in the treatment process.

[0004] However, the aforementioned existing technologies have significant shortcomings in dealing with complex operating conditions and achieving deep resource recovery: First, existing systems often operate waste gas absorption and wastewater treatment separately. The high-concentration fluoride-containing mother liquor generated from waste gas absorption is often directly discharged or simply mixed into the wastewater, failing to be effectively utilized as a reaction agent for reuse, resulting in high agent consumption and low fluoride recovery rate; Second, traditional biological treatment units struggle to cope with the interference of residual recalcitrant organic matter and trace fluoride ions in fluoride-containing wastewater, lacking targeted sludge-water separation and sludge solidification processes, leading to large fluctuations in effluent quality and a high risk of exceeding standards; Third, The existing system has a low level of automation control and lacks a linkage feedback mechanism based on real-time monitoring data. For example, it cannot automatically trigger reflux reprocessing when online monitoring exceeds the standard, and exhaust gas emissions are greatly affected by meteorological conditions, lacking dynamic adjustment means. Finally, the capacity for deep processing of by-products is insufficient. Most facilities only stop at primary precipitation or simple crystallization, lacking refined resource recovery methods such as multi-effect evaporation and centrifugal drying. Furthermore, a unified intelligent operation and maintenance platform has not been established to coordinate the scheduling and fault early warning of all equipment in the plant, making it difficult to meet the high standards of modern industry for system stability, safety, and maximum resource utilization. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a system for the synergistic treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid. It has the advantages of deep purification through gas-liquid synergy and efficient recycling of fluorine, thus solving the problem of low efficiency in the separate treatment of waste gas and waste liquid in traditional processes.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a system for the synergistic treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid, comprising a collection and pretreatment module, a deep chemical purification module, a biochemical separation module, a standard emission control module, and a resource intelligent control module, with the specific functions as follows:

[0007] Collection and pretreatment module: used for the separate collection of fluoride-containing gas and liquid, water quality and quantity balancing, and impurity interception;

[0008] Chemical deep purification module: Utilizing multi-stage precipitation and absorption processes, dissolved fluorides are efficiently converted into solids or high-concentration salt solutions;

[0009] Biochemical separation module: It degrades residual organic matter through biochemical reactions and completes mud-water separation and sludge solidification with the help of filter press equipment;

[0010] The emission control module for compliance: performs fine filtration of effluent and high-altitude emission of exhaust gas, relying on online monitoring and dual-fan redundancy;

[0011] Resource intelligent control module: Deeply processes by-products to achieve fluorine resource recovery, and uses the intelligent control platform for unified scheduling and fault early warning;

[0012] The collection and pretreatment module includes a fluoride-containing wastewater receiving unit, which includes an equalization tank, a pH monitor, and an inlet valve group for the integrated wastewater equalization tank. It is used to balance water quality and quantity, stabilize the pH value of the influent, and intercept large particulate impurities. The fluoride-containing wastewater receiving unit includes a gas collection hood, a waste gas filter, and a pneumatic valve. It is used to physically separate and collect acidic waste gas generated in the workshop and preliminarily purify it before transporting it to the absorption tower.

[0013] The deep chemical purification module includes a wastewater defluorination unit and a waste gas absorption unit. The wastewater defluorination unit includes a dosing pump set, a mechanical stirrer, and a reaction sedimentation tank, and is used to add lime / PAC reagent to cause dissolved fluoride ions to undergo a chemical reaction to generate solid precipitate. The waste gas absorption unit includes a multi-stage falling film absorption tower, an alkaline solution circulation pump, and a packing layer, and is used to efficiently absorb fluorides in acidic gases through gas-liquid countercurrent contact and convert them into high-concentration salt solution.

[0014] The wastewater defluorination unit and the waste gas absorption unit in the chemical deep purification module are connected by a gas-liquid heat exchange circuit. The high-concentration fluoride-containing salt solution generated by the waste gas absorption unit is pumped to the dosing tank of the wastewater defluorination unit for reuse as a neutralizing agent. The bottom of the reaction sedimentation tank is equipped with an inclined plate settling zone and the top is equipped with a sludge scraper to accelerate the separation speed of calcium fluoride precipitate and reduce the water content of sludge.

[0015] Furthermore, the biochemical separation module includes an A² / O biochemical treatment unit and a sludge dewatering unit. The A² / O biochemical treatment unit includes an anaerobic tank, an anoxic tank, an aerobic tank, and an aeration system, and is used to utilize microorganisms to degrade residual organic matter and achieve nitrogen and phosphorus removal. The sludge dewatering unit includes a secondary sedimentation tank, a sludge return pump, and a plate and frame filter press, and is used to complete sludge-water separation and dewater and solidify fluoride-containing sludge for safe disposal.

[0016] Furthermore, the emission control module includes a clean water storage unit and an exhaust gas emission unit. The clean water storage unit includes a fine filter, a clean water tank, and an online COD / fluoride ion monitor, and is used to perform final fine filtration on the effluent and monitor it in real time to ensure that the emission indicators are qualified. The exhaust gas emission unit includes a main and backup dual fan, a flame arrester, and a high-altitude chimney, and is used to pressurize and transport the purified exhaust gas to achieve qualified high-altitude emission.

[0017] Furthermore, the resource intelligent control module includes a by-product recovery unit and an intelligent operation and maintenance unit. The by-product recovery unit includes an evaporator crystallizer, a centrifuge, and a storage silo, and is used to further process high-concentration NaF solution or CaF2 sludge to achieve fluorine resource recovery and utilization. The intelligent operation and maintenance unit includes a DCS / SIS control system, a data dashboard, and a fault alarm device, and is used to uniformly schedule the operating parameters of all equipment in the plant and achieve unattended operation and automatic early warning.

[0018] Furthermore, the A² / O biochemical treatment unit and the sludge dewatering unit in the biochemical separation module are connected by a sludge return pipeline. The sludge return pipeline is equipped with a proportional regulating valve, which is used to return the activated sludge at the bottom of the secondary sedimentation tank to the front end of the anaerobic tank at a set ratio to maintain the microbial concentration. The feed end of the plate and frame filter press is connected to an automatic dosing device, which is used to add flocculant to the sludge before filtration to optimize the dewatering effect.

[0019] Furthermore, the clean water storage unit in the emission control module is equipped with a data linkage control valve group between itself and the online monitoring instrument. When the online COD / fluoride ion monitoring instrument detects that the effluent indicators exceed the standards, the control valve group automatically triggers the bypass backflow mechanism to guide the unqualified water back to the regulating tank for reprocessing. In addition, the high-altitude chimney of the exhaust gas emission unit is equipped with a wind speed and direction sensor, whose signal is connected to the intelligent operation and maintenance unit to dynamically adjust the operating frequency of the dual fans according to meteorological conditions to ensure the diffusion effect.

[0020] Furthermore, the by-product recovery unit in the resource intelligent control module includes a multi-effect evaporation crystallization system, which includes a preheater, an evaporator, and a centrifugal dryer, used to concentrate and crystallize high-concentration NaF solution; and the DCS / SIS control system in the intelligent operation and maintenance unit communicates bidirectionally with the PLC controllers of each module via industrial Ethernet.

[0021] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0022] 1. This system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and liquid achieves integrated gas-liquid separation collection, deep purification, and resource recycling. Utilizing multi-stage precipitation and absorption processes, the system efficiently converts dissolved fluorides into solid precipitates or high-concentration salt solutions. It also innovatively designs a gas-liquid heat exchange loop, allowing the high-concentration fluoride-containing mother liquor generated from waste gas absorption to be reused as a neutralizing agent in the wastewater defluorination process. This significantly reduces the consumption of reagents such as lime and avoids the generation of high-concentration... The direct discharge of brine significantly improves the recovery and utilization rate of fluoride. It integrates the A² / O biochemical treatment unit and the plate and frame filter press dewatering unit, effectively degrading residual organic matter and achieving solidification and volume reduction of fluoride-containing sludge. Combined with online monitoring and an automatic return mechanism for exceeding standards, it ensures that the effluent quality consistently meets the standards. Furthermore, the introduction of multi-effect evaporation crystallization and intelligent operation and maintenance platform allows for the deep processing of by-products into high-purity fluoride salt products, truly realizing a green transformation from end-of-pipe treatment to source reduction, process control, and resource recycling, with significant environmental and economic benefits.

[0023] 2. This system for the co-treatment and resource recovery of hydrofluoric acid waste gas and liquid, through deep integration of the DCS / SIS control system and industrial Ethernet, constructs a closed-loop control network integrating data acquisition, fault self-diagnosis, remote scheduling, and historical trend analysis. It achieves unified management and unattended operation of all plant equipment operating parameters, reducing the risks of manual operation and maintenance costs. The system has the function of adjusting the frequency of dual fans in conjunction with wind speed and direction sensors, which can dynamically optimize the exhaust gas diffusion effect according to meteorological conditions, and automatically trigger bypass recirculation reprocessing when the effluent indicators are abnormal, completely eliminating the accident of excessive emission due to monitoring lag. The configuration of the inclined plate settling zone and automatic dosing device further optimizes the solid-liquid separation efficiency, enabling the entire system to maintain high stability and high reliability when dealing with complex operating condition fluctuations, providing a replicable technical paradigm for clean production in the fluorinated chemical industry. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the waste liquid treatment process of the present invention;

[0025] Figure 2 This is a schematic diagram of the waste gas treatment process of the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figure 1-2 This embodiment of a system for the synergistic treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid includes a collection and pretreatment module, a deep chemical purification module, a biochemical separation module, a standard emission control module, and a resource intelligent control module, with the following specific functions:

[0028] Collection and pretreatment module: used for the separate collection of fluoride-containing gas and liquid, water quality and quantity balancing, and impurity interception;

[0029] Chemical deep purification module: Utilizing multi-stage precipitation and absorption processes, dissolved fluorides are efficiently converted into solids or high-concentration salt solutions;

[0030] Biochemical separation module: It degrades residual organic matter through biochemical reactions and completes mud-water separation and sludge solidification with the help of filter press equipment;

[0031] The emission control module for compliance: performs fine filtration of effluent and high-altitude emission of exhaust gas, relying on online monitoring and dual-fan redundancy;

[0032] Resource intelligent control module: It performs deep processing of by-products to achieve fluorine resource recovery, and uses the intelligent control platform for unified scheduling and fault early warning.

[0033] It should be noted that by constructing a collaborative system comprising five modules—collection and pretreatment, deep chemical purification, biochemical separation, emission control to meet standards, and intelligent resource control—the system achieves integrated collection, deep purification, and resource recovery of fluorine-containing waste gas and waste liquid, solving the problems of dispersed gas and liquid treatment, low resource utilization, and low automation in traditional processes.

[0034] Furthermore, the collection and pretreatment module includes a fluoride-containing wastewater receiving unit, which includes an equalization tank, a pH monitor, and an inlet valve group for the integrated wastewater equalization tank. It is used to balance water quality and quantity, stabilize the pH value of the influent, and intercept large particulate impurities. The fluoride-containing wastewater receiving unit includes a gas collection hood, a waste gas filter, and a pneumatic valve. It is used to physically separate and collect acidic waste gas generated in the workshop and preliminarily purify it before transporting it to the absorption tower.

[0035] It should be noted that the collection and pretreatment module has been refined. By setting up an equalization tank, pH monitor and integrated wastewater regulating valve group, the water quality and quantity are effectively balanced and the influent pH value is stabilized. At the same time, the physical separation and preliminary purification of acidic waste gas are achieved by using a gas collection hood and filter screen, which significantly improves the influent stability and shock resistance of the subsequent treatment system.

[0036] Furthermore, the chemical deep purification module includes a wastewater defluorination unit and a waste gas absorption unit. The wastewater defluorination unit includes a dosing pump set, a mechanical stirrer, and a reaction sedimentation tank, and is used to add lime / PAC reagent to cause dissolved fluoride ions to undergo a chemical reaction to generate solid precipitate. The waste gas absorption unit includes a multi-stage falling film absorption tower, an alkaline solution circulation pump, and a packing layer, and is used to efficiently absorb fluorides in acidic gases through gas-liquid countercurrent contact and convert them into high-concentration salt solution.

[0037] It should be noted that the core process of the deep chemical purification module has been clarified. It utilizes a dosing pump set and a mechanical agitator to efficiently generate solid precipitates in the reaction sedimentation tank. Combined with the gas-liquid countercurrent contact technology of the multi-stage falling film absorption tower, dissolved fluorides are converted into high-concentration salt solutions, which greatly improves the removal efficiency and conversion purity of fluorides.

[0038] Furthermore, the biochemical separation module includes an A² / O biochemical treatment unit and a sludge dewatering unit. The A² / O biochemical treatment unit includes an anaerobic tank, an anoxic tank, an aerobic tank, and an aeration system, and is used to utilize microorganisms to degrade residual organic matter and achieve nitrogen and phosphorus removal. The sludge dewatering unit includes a secondary sedimentation tank, a sludge return pump, and a plate and frame filter press, and is used to complete sludge-water separation and dewater and solidify fluoride-containing sludge for safe disposal.

[0039] It should be noted that the A² / O unit and sludge dewatering unit of the biochemical separation module are described in detail. Through the synergistic effect of anaerobic, anoxic, and aerobic tanks, residual organic matter is degraded and nitrogen and phosphorus are removed. Combined with a plate and frame filter press, sludge-water separation and sludge solidification are completed, which effectively reduces the sludge moisture content and facilitates safe disposal.

[0040] Furthermore, the emission control module includes a clean water storage unit and an exhaust gas emission unit. The clean water storage unit includes a fine filter, a clean water tank, and an online COD / fluoride ion monitor, and is used to perform final fine filtration on the effluent and monitor it in real time to ensure that the emission indicators are qualified. The exhaust gas emission unit includes a main and backup dual fan, a flame arrester, and a high-altitude chimney, and is used to pressurize and transport the purified exhaust gas to achieve qualified high-altitude emission.

[0041] It should be noted that the fine filtration and emission process of the emission control module has been standardized. The fine filter and online COD / fluoride ion monitor ensure that the effluent indicators are qualified in real time. The main and backup fans and flame arresters are used to ensure the safety and reliability of the exhaust gas pressurization and delivery, eliminating the risk of exceeding emission standards.

[0042] Furthermore, the resource intelligent control module includes a by-product recovery unit and an intelligent operation and maintenance unit. The by-product recovery unit includes an evaporator crystallizer, a centrifuge, and a storage silo, and is used to further process high-concentration NaF solution or CaF2 sludge to achieve fluorine resource recovery and utilization. The intelligent operation and maintenance unit includes a DCS / SIS control system, a data dashboard, and a fault alarm device, and is used to uniformly schedule the operating parameters of all equipment in the plant and achieve unattended operation and automatic early warning.

[0043] It should be noted that the resource intelligent control module is highlighted. It utilizes a multi-effect evaporation crystallization system to process by-products into high-purity fluoride salt products. Through the DCS / SIS control system and data dashboard, it achieves unified scheduling of all equipment in the plant, unattended operation, and automatic fault early warning, which greatly improves the system's intelligence level and economic benefits.

[0044] Furthermore, a gas-liquid heat exchange circuit is provided between the wastewater defluorination unit and the waste gas absorption unit in the chemical deep purification module. The high-concentration fluoride-containing salt solution generated by the waste gas absorption unit is pumped to the dosing tank of the wastewater defluorination unit for reuse as a neutralizing agent. The bottom of the reaction sedimentation tank is provided with an inclined plate settling zone, and the top is provided with a sludge scraper to accelerate the separation speed of calcium fluoride precipitate and reduce the water content of sludge.

[0045] It should be noted that a gas-liquid heat exchange circuit was designed to reuse the high-concentration fluoride-containing mother liquor generated from the absorption of waste gas as a neutralizing agent in the wastewater defluorination process. This not only significantly reduces the consumption of reagents such as lime, but also accelerates the separation of precipitates in combination with the inclined plate settling zone, thereby significantly improving the recovery rate of fluoride and the economic efficiency of the system operation.

[0046] Furthermore, the A² / O biochemical treatment unit and the sludge dewatering unit in the biochemical separation module are connected by a sludge return pipeline. The sludge return pipeline is equipped with a proportional regulating valve, which is used to return the activated sludge at the bottom of the secondary sedimentation tank to the front end of the anaerobic tank at a set ratio to maintain the microbial concentration. The feed end of the plate and frame filter press is connected to an automatic dosing device, which is used to add flocculant to the sludge before filtration to optimize the dewatering effect.

[0047] It should be noted that the internal circulation mechanism of the biochemical separation module has been optimized. The precise return of activated sludge is achieved through a proportional regulating valve to maintain the concentration of microorganisms. An automatic dosing device is introduced before the plate and frame filter press to optimize the flocculation effect, ensuring that the system still has efficient organic matter degradation capacity and excellent sludge dewatering performance under complex operating conditions.

[0048] Furthermore, the clean water storage unit in the emission control module is equipped with a data linkage control valve group between itself and the online monitoring instrument. When the online COD / fluoride ion monitoring instrument detects that the effluent indicators exceed the standards, the control valve group automatically triggers the bypass backflow mechanism to guide the unqualified water back to the regulating tank for reprocessing. In addition, the high-altitude chimney of the exhaust gas emission unit is equipped with a wind speed and direction sensor, whose signal is connected to the intelligent operation and maintenance unit to dynamically adjust the operating frequency of the dual fans according to meteorological conditions to ensure the diffusion effect.

[0049] It should be noted that an intelligent linkage control strategy has been constructed. When the online monitoring instrument detects that the effluent exceeds the standard, the bypass backflow reprocessing mechanism is automatically triggered, which eliminates emission accidents caused by human delay. At the same time, the frequency of the dual fans is dynamically adjusted by wind speed and direction sensors to optimize exhaust gas diffusion and enhance the system's adaptability to environmental changes.

[0050] Furthermore, the by-product recovery unit in the resource intelligent control module includes a multi-effect evaporation crystallization system, which includes a preheater, an evaporator, and a centrifugal dryer, used to concentrate and crystallize high-concentration NaF solution; and the DCS / SIS control system in the intelligent operation and maintenance unit communicates bidirectionally with the PLC controllers of each module via industrial Ethernet.

[0051] It should be noted that the by-product deep processing and closed-loop control network has been improved. A multi-effect evaporation crystallization system is used to achieve efficient concentration and crystallization of high-concentration solutions. The DCS / SIS system and PLC controller are bidirectionally communicated through industrial Ethernet. Data acquisition, self-diagnosis, remote scheduling and trend analysis functions are integrated to realize full-process digital intelligent management.

[0052] The working principle of the above embodiments is as follows:

[0053] Firstly, the system is built upon a collaborative treatment and resource recovery mechanism for hydrofluoric acid-containing waste gas and liquid. After system startup, the fluorine-containing waste gas first enters a multi-stage absorption tower, where the circulating alkaline absorbent efficiently converts gaseous fluorides into dissolved fluoride ions. The resulting high-concentration fluorine-containing mother liquor is not directly discharged but is transported to the wastewater defluorination unit via an innovative gas-liquid heat exchange loop, where it is reused as a neutralizing agent to treat fluorine-containing wastewater. This achieves internal recycling of gas and liquid resources, significantly reducing the consumption of external agents such as lime. Simultaneously, the pre-treated wastewater... The effluent enters the A2 / O biochemical reaction tank, where microorganisms degrade residual organic matter. It then flows into the inclined plate settling zone for solid-liquid separation. The precipitated fluoride-containing sludge is dewatered by plate and frame filter press to form dry sludge cake, while the clarified supernatant enters the multi-effect evaporation crystallization system. Under vacuum, it is concentrated to precipitate high-purity fluoride crystals, ultimately achieving the resource recovery of fluoride. Throughout the process, the online monitoring system tracks key indicators in real time. If the effluent or exhaust gas data is abnormal, the system will automatically trigger the bypass reflux mechanism to send the unqualified fluid back to the front end of the treatment, ensuring stable compliance of the entire process.

[0054] In terms of intelligent control and safety interlocking, this system relies on the deep integration of the DCS distributed control system and the SIS safety instrumented system to build a closed-loop control network based on industrial Ethernet. This enables real-time data acquisition, fault self-diagnosis, and remote scheduling management of the operating status of all equipment in the plant. The system's built-in intelligent algorithm can dynamically adjust the operating frequency of the dual fans based on real-time feedback from wind speed and direction sensors, optimize the diffusion effect of exhaust gas, and prevent local concentration accumulation. When the effluent fluoride concentration exceeds the standard or the pH value fluctuates, the control center will immediately and automatically shut off the discharge valve and start the return pump to forcibly send the abnormal water back to the front-end treatment unit for secondary purification, completely eliminating the risk of excessive discharge caused by delayed manual operation. In addition, the linkage design of the automatic dosing device and the inclined plate settling zone further optimizes the solid-liquid separation efficiency, enabling the system to maintain extremely high operational stability and reliability when dealing with complex operating conditions such as fluctuations in raw material composition or load changes. This truly realizes the green transformation from traditional end-of-pipe treatment to source reduction, precise process control, and deep resource recovery.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0056] 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 system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid, characterized in that, It includes a collection and pretreatment module, a chemical deep purification module, a biochemical separation module, a compliance emission control module, and a resource intelligent control module, with the following specific functions: Collection and pretreatment module: used for the separate collection of fluoride-containing gas and liquid, water quality and quantity balancing, and impurity interception; Chemical deep purification module: Utilizing multi-stage precipitation and absorption processes, dissolved fluorides are efficiently converted into solids or high-concentration salt solutions; Biochemical separation module: It degrades residual organic matter through biochemical reactions and completes mud-water separation and sludge solidification with the help of filter press equipment; The emission control module for compliance: performs fine filtration of effluent and high-altitude emission of exhaust gas, relying on online monitoring and dual-fan redundancy; Resource intelligent control module: Deeply processes by-products to achieve fluorine resource recovery, and uses the intelligent control platform for unified scheduling and fault early warning; The collection and pretreatment module includes a fluoride-containing wastewater receiving unit, which includes an equalization tank, a pH monitor, and an inlet valve group for the integrated wastewater equalization tank. It is used to balance water quality and quantity, stabilize the pH value of the influent, and intercept large particulate impurities. The fluoride-containing wastewater receiving unit includes a gas collection hood, a waste gas filter, and a pneumatic valve. It is used to physically separate and collect acidic waste gas generated in the workshop and preliminarily purify it before transporting it to the absorption tower. The deep chemical purification module includes a wastewater defluorination unit and a waste gas absorption unit. The wastewater defluorination unit includes a dosing pump set, a mechanical stirrer, and a reaction sedimentation tank, and is used to add lime / PAC reagent to cause dissolved fluoride ions to undergo a chemical reaction to generate solid precipitate. The waste gas absorption unit includes a multi-stage falling film absorption tower, an alkaline solution circulation pump, and a packing layer, and is used to efficiently absorb fluorides in acidic gases through gas-liquid countercurrent contact and convert them into high-concentration salt solution. The wastewater defluorination unit and the waste gas absorption unit in the chemical deep purification module are connected by a gas-liquid heat exchange circuit. The high-concentration fluoride-containing salt solution generated by the waste gas absorption unit is pumped to the dosing tank of the wastewater defluorination unit for reuse as a neutralizing agent. The bottom of the reaction sedimentation tank is equipped with an inclined plate settling zone and the top is equipped with a sludge scraper to accelerate the separation speed of calcium fluoride precipitate and reduce the water content of sludge.

2. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 1, characterized in that: The biochemical separation module includes an A² / O biochemical treatment unit and a sludge dewatering unit. The A² / O biochemical treatment unit includes an anaerobic tank, an anoxic tank, an aerobic tank, and an aeration system, and is used to utilize microorganisms to degrade residual organic matter and achieve nitrogen and phosphorus removal. The sludge dewatering unit includes a secondary sedimentation tank, a sludge return pump, and a plate and frame filter press, and is used to complete sludge-water separation and dewater and solidify fluoride-containing sludge for safe disposal.

3. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 1, characterized in that: The emission control module includes a clean water storage unit and an exhaust gas emission unit. The clean water storage unit includes a fine filter, a clean water tank, and an online COD / fluoride ion monitor, and is used to perform final fine filtration on the effluent and monitor it in real time to ensure that the emission indicators are qualified. The exhaust gas emission unit includes a main and backup dual fan, a flame arrester, and a high-altitude chimney, and is used to pressurize and transport the purified exhaust gas to achieve compliant high-altitude emission.

4. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 1, characterized in that: The resource intelligent control module includes a by-product recovery unit and an intelligent operation and maintenance unit. The by-product recovery unit includes an evaporator crystallizer, a centrifuge, and a storage silo, and is used to further process high-concentration NaF solution or CaF2 sludge to achieve fluorine resource recovery and utilization. The intelligent operation and maintenance unit includes a DCS / SIS control system, a data dashboard, and a fault alarm device, and is used to uniformly schedule the operating parameters of all equipment in the plant and achieve unattended operation and automatic early warning.

5. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 2, characterized in that: The A² / O biochemical treatment unit and the sludge dewatering unit in the biochemical separation module are connected by a sludge return pipeline. The sludge return pipeline is equipped with a proportional regulating valve, which is used to return the activated sludge at the bottom of the secondary sedimentation tank to the front end of the anaerobic tank at a set ratio to maintain the microbial concentration. The feed end of the plate and frame filter press is connected to an automatic dosing device, which is used to add flocculant to the sludge before filtration to optimize the dewatering effect.

6. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 3, characterized in that: The clean water storage unit in the emission control module is connected to the online monitoring instrument via a data linkage control valve group. When the online COD / fluoride ion monitoring instrument detects that the effluent indicators exceed the standards, the control valve group automatically triggers the bypass backflow mechanism to guide the unqualified water back to the regulating tank for reprocessing. Furthermore, the exhaust gas emission unit is equipped with a wind speed and direction sensor on its high-altitude chimney, and its signal is connected to the intelligent operation and maintenance unit to dynamically adjust the operating frequency of the dual fans according to meteorological conditions to ensure the diffusion effect.

7. The system for the co-treatment and resource recovery of hydrofluoric acid-containing waste gas and waste liquid according to claim 4, characterized in that: The by-product recovery unit in the resource intelligent control module includes a multi-effect evaporation crystallization system, which includes a preheater, an evaporator, and a centrifugal dryer, used to concentrate and crystallize high-concentration NaF solution; and the DCS / SIS control system in the intelligent operation and maintenance unit communicates bidirectionally with the PLC controllers of each module via industrial Ethernet.

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