Treatment system and method for organic fluorine-containing sewage and application

Abstract

The invention discloses a treatment system and method for organic fluorine-containing sewage and application, and belongs to the field of water treatment. The system comprises a parameter setting and control unit, a pretreatment unit, an incoming water detection unit, a pretreatment unit, a perfluorinated and polyfluoroalkyl substance separate treatment unit, a regeneration unit and a mechanical unit, incoming water is detected firstly, and then sewage with different pollutants is selectively conveyed into the corresponding units to be treated; meanwhile, the system comprises units for treating perfluorinated and polyfluoroalkyl substances with different chain lengths, treatment of different standards can be achieved, energy is saved, operation is convenient, application is wide, and convenience is achieved.

Description

Technical Field

[0001] This invention relates to the field of water treatment, and more specifically to a treatment system, method, and application for wastewater containing organic fluoride. Background Technology

[0002] Perfluorinated and polyfluoroalkyl substances (PFAS) are known as "permanent chemicals" in the industry due to their extremely strong carbon-fluorine bonds in their molecular structure, which give them significant persistence, bioaccumulation, and long-distance migration capabilities. As toxicological research continues to deepen, the potential hazards of PFAS to the ecological environment and human health are gradually being revealed. Various companies have also included multiple PFAS in their control or emission restriction lists, imposing stringent requirements on the residual limits of PFAS in water bodies.

[0003] However, most existing water treatment systems are still based on a combination of coagulation-sedimentation-sand filtration-disinfection, or an anaerobic-anoxic-aerobic-secondary sedimentation-advanced treatment combination. These systems cannot be specifically designed for the unique physicochemical properties of PFAS, resulting in numerous systemic shortcomings in the treatment of PFAS-contaminated water. To address the targeted removal of PFAS, CN113508093A discloses a system and method for removing stubborn organic compounds from water, including perfluorinated and polyfluoroalkyl substances. Specifically, this invention relates to a system and method for removing such pollutants from water using submicron powdered activated carbon combined with ceramic membrane filtration. However, this method uses ultrafine powdered activated carbon (SPAC) as the adsorbent for PFAS. After thorough mixing with the influent, the activated carbon is directly pumped into a high-speed ceramic membrane filtration device, operating in a cross-flow filtration mode with periodic backflow cleaning. However, since the powdered activated carbon and influent are not filtered directly, the membrane module is easily clogged, reducing the membrane's lifespan. Furthermore, the system lacks pretreatment facilities for incoming water. Large molecular pollutants in the incoming water will compete with PFAS molecules for adsorption sites on the powdered activated carbon or clog the pores, thus reducing the adsorption of micro-pollutants such as PFAS. In addition, the ultrafine powdered activated carbon used in the system is directly removed and discarded after dehydration and concentration, increasing the amount of activated carbon used and operating costs. At the same time, the powdered activated carbon that has adsorbed PFAS may also pose a risk of secondary pollution to the environment.

[0004] WOIB20000618 discloses a method for treating PFAS in liquid effluent, proposing real-time monitoring of PFAS type and concentration in the influent, activating the PFAS treatment unit only upon detection, and intelligently matching and activating different treatment units simultaneously based on PFAS chain length, while optimizing their optimal treatment process parameters in real time. However, this scheme also lacks necessary raw water pretreatment equipment to reduce or remove the impact of other high-concentration organic matter or suspended solids in the raw water on PFAS removal. Furthermore, adsorption technology, primarily using activated carbon and ion exchange resins, is the main PFAS treatment pathway in this method, but it does not specify whether the adsorbent adsorbed with PFAS is regenerated or the regeneration method.

[0005] Therefore, in the existing technology for treating wastewater containing organic fluoride, there are still problems that urgently need to be solved, such as the easy clogging of activated carbon, low efficiency of activated carbon, the influence of dissolved organic matter in the influent, and the difficulty in removing short-chain perfluorinated and polyfluoroalkyl substances. Summary of the Invention

[0006] To address the above problems, this invention provides a treatment system, method, and application for wastewater containing organofluorine compounds. By first testing the incoming water, wastewater with different pollutants is selectively transported to the corresponding units for treatment. The system includes units for treating perfluorinated and polyfluoroalkyl substances with different chain lengths, enabling treatment to meet different standards. It is energy-saving, easy to operate, and has a wide range of applications.

[0007] This invention provides a treatment system for wastewater containing organic fluoride, the treatment system for wastewater containing organic fluoride includes a parameter setting and control unit, a pretreatment unit, an influent detection unit, a pretreatment unit, a perfluorinated and polyfluoroalkyl substances (PFAS) separation and treatment unit, a regeneration unit and a mechanical unit; The parameter setting and control unit is connected to the pretreatment unit, the incoming water detection unit, the pretreatment unit, the perfluorinated and polyfluoroalkyl substances separation unit, and the regeneration unit; The pretreatment unit is connected in series with the incoming water detection unit; The incoming water detection unit is connected in parallel with the pretreatment unit; The pretreatment unit is connected in series with the perfluorinated and polyfluoroalkyl substances separation unit; The regeneration unit is cyclically connected to the perfluorinated and polyfluoroalkyl substances separation unit; The parameter setting and control unit, the pretreatment unit, the incoming water detection unit, the pretreatment unit, the perfluorinated and polyfluoroalkyl substances separation unit, and the regeneration unit are all fixed on the mechanical unit; The detection limit range for perfluorinated and polyfluoroalkyl substances in the wastewater containing organofluorine by the treatment system is ng-mg / L, and the lowest detection limit is 1-2ng / L. The chain length of the perfluorinated and polyfluoroalkyl substances detected is C2-C20.

[0008] Furthermore, the treatment system for organofluorine wastewater has a removal rate of 80-99% for perfluorinated and polyfluoroalkyl substances, and can complete the treatment within 2-3 hours, with the effluent meeting the standards and requiring no additional treatment processes.

[0009] Furthermore, the parameter setting and control unit includes a scene database module, a parameter adjustment module, an operation monitoring module, and a regeneration control module.

[0010] Furthermore, the scenario database module includes at least the following standards: drinking water quality standards (GB 5749-2022), surface water quality standards (GB 3838-2002), groundwater quality standards (GB / T 14848-2017), wastewater discharge standards (GB8978-1996), farmland irrigation water quality standards (GB 5084-2021), fishery water quality standards (GB 11607-1989), landscape and recreational water quality standards (GB 12941-2019), industrial boiler water quality standards (GB / T 1576-2018), the U.S. National Drinking Water Standards, and the European Union Drinking Water Directive.

[0011] Furthermore, the parameter setting and control unit sets a program based on the water quality standards in the scenario database module through the parameter control module. Combined with the various indicators of the organic fluoride-containing wastewater detected by the operation monitoring module in the incoming water detection unit and the pretreatment unit, the parameter control module sets specific treatment programs for the pretreatment unit and the perfluorinated and polyfluoroalkyl substances separation unit to treat the organic fluoride-containing wastewater. Then, the regeneration control module detects the adsorption capacity of activated carbon or cyclodextrin polymer in the perfluorinated and polyfluoroalkyl substances separation unit and regenerates it.

[0012] Furthermore, the pretreatment unit includes a filtration device and a regulating device in sequence according to the direction of sewage flow.

[0013] Furthermore, the filtration device is a filter needle or filter, and the filtration device is provided with a polyethersulfone filter membrane, the pore size of which is 0.3-0.5μm.

[0014] Furthermore, the regulating device is equipped with HCl and NaOH dosing devices to adjust the pH of the wastewater to 6-8.

[0015] Furthermore, the incoming water detection unit includes a non-targeting section and a targeting section in sequence according to the direction of sewage flow.

[0016] Furthermore, the sampling port of the non-targeted segment is equipped with an automatic sampling valve, and the material of the automatic sampling valve is polyethylene or polyvinyl chloride.

[0017] Furthermore, the sampling frequency of the non-target segment is 5-10 min, and the single sampling volume is 50-100 mL.

[0018] Furthermore, a high-resolution time-of-flight mass spectrometer (HRMS) is installed in the non-target segment, which is used for preliminary qualitative and quantitative analysis of perfluorinated and polyfluoroalkyl substances.

[0019] Furthermore, the high-resolution time-of-flight mass spectrometer (HRMS) is used to preliminarily detect whether the organofluorine-containing wastewater contains perfluorinated and polyfluoroalkyl substances with CF bonds, and to preliminarily determine the total amount of CF bonds in the organofluorine-containing wastewater.

[0020] Furthermore, the time taken for the preliminary measurement is ≤30s.

[0021] Furthermore, a triple quadrupole mass spectrometer is installed in the target segment.

[0022] Furthermore, the triple quadrupole mass spectrometer is used for the precise quantification of perfluorinated and polyfluoroalkyl substances and the analysis of their types.

[0023] Furthermore, the detection limit of the triple quadrupole mass spectrometer is set to 1-2 ng / L, and the detection accuracy is <15-25%.

[0024] Furthermore, the pretreatment unit includes a water quality detection unit and a water quality treatment unit in sequence according to the direction of sewage flow.

[0025] Furthermore, the water quality detection unit includes, in order of flow direction of the wastewater, at least a turbidity sensor, a total organic carbon (TOC) rapid analyzer, a total dissolved solids (TDS) sensor, a pH meter, and a temperature sensor.

[0026] Furthermore, the water treatment unit corresponds to the water quality detection unit, and according to the direction of sewage flow, it includes at least a suspended solids treatment tank, an organic matter treatment tank, a high salinity treatment tank, an acid-base treatment tank, and a heat exchanger in sequence.

[0027] Furthermore, the suspended solids treatment tank includes a clarification tank and a sand filter tank in sequence.

[0028] Furthermore, the organic matter treatment tank includes, in sequence, an activated carbon adsorption tank and an ozone tank.

[0029] Furthermore, the high-salinity water treatment tank contains a cation exchange column.

[0030] Furthermore, the acid-base treatment tank is divided into an alkali tank and an acid tank, wherein the alkali in the alkali tank is NaOH and the acid tank is HCl, and the pH of the treated water is 6-8.

[0031] Furthermore, the temperature of the water after heat exchange in the heat exchanger is 20-30℃.

[0032] Furthermore, the pretreatment unit can remove some organic matter other than perfluorinated and polyfluoroalkyl substances, and also eliminates the interference of other ions, keeping the organic fluorine-containing wastewater within the normal pH range, so as not to affect the subsequent PFAS treatment. At the same time, the removal of suspended solids also reduces its impact on the treatment efficiency of the subsequent perfluorinated and polyfluoroalkyl substance separation unit.

[0033] Furthermore, the perfluorinated and polyfluoroalkyl substances separation unit includes a short-chain processing unit, a long-chain processing unit, and a comprehensive processing unit.

[0034] Furthermore, the short-chain processing unit is used to remove perfluorinated and polyfluoroalkyl substances with chain lengths of C2-C7.

[0035] Furthermore, the short-chain processing unit includes a cyclodextrin polymer dosing device, an oxidant dosing device, and a strongly basic anion exchange column.

[0036] Furthermore, the short-chain processing unit has a removal rate of ≥99% for perfluorinated and polyfluoroalkyl substances with chain lengths of C4-C6.

[0037] Furthermore, the short-chain processing unit also includes an electrochemical catalytic device or a photocatalytic device.

[0038] Furthermore, the long-chain processing unit is used to remove perfluorinated and polyfluoroalkyl substances with chain lengths of C6-C20.

[0039] Furthermore, the long-chain processing unit includes an activated carbon dosing device, an oxidant dosing device, a strong base anion exchange column, and a ceramic membrane ultrafiltration device.

[0040] Furthermore, the activated carbon, oxidant, ion exchange column, and ceramic membrane ultrafiltration device in the long-chain treatment unit achieve a removal rate of 80-90% for long-chain perfluorinated and polyfluoroalkyl substances.

[0041] Furthermore, the integrated treatment unit includes an activated carbon dosing device, an oxidant dosing device, a strong base anion exchange column, a ceramic membrane ultrafiltration device, and a nanofiltration / reverse osmosis device.

[0042] Furthermore, the regeneration unit includes an activated carbon regeneration device.

[0043] Furthermore, the activated carbon regeneration device is either an in-situ regeneration device or a non-in-situ regeneration device.

[0044] Furthermore, the activated carbon regeneration device performs thermal regeneration or solvent regeneration of the activated carbon.

[0045] Furthermore, the mechanical unit has a box-type structure.

[0046] Furthermore, the parameter setting and control unit, the pretreatment unit, the incoming water detection unit, the pretreatment unit, the perfluorinated and polyfluoroalkyl substances separation unit, and the regeneration unit are all fixed in the box structure of the mechanical unit by bolts, and the devices of each unit are sealed and connected by pipes, flanges, and sealing rings.

[0047] Furthermore, the bottom of the box-shaped structure of the mechanical unit is equipped with pulleys for easy movement of the mechanical unit.

[0048] Furthermore, the organic fluorine in the wastewater containing organic fluorine includes at least perfluorinated and polyfluoroalkyl substances.

[0049] The present invention also provides a treatment method for the aforementioned wastewater treatment system containing organofluorine, comprising the following steps: Step 1: Before treating wastewater containing organic fluoride, first set the water quality standards for treatment through parameter settings and the scenario database module in the control unit; Step 2: After pretreatment, the wastewater containing organic fluorine is directly fed into the non-targeted and targeted sections of the incoming water detection unit to determine the total amount and content of different types of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluorine. Step 3: After quantitative and qualitative analysis of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluorine, it is introduced into the pretreatment unit and measured using a turbidity sensor, a rapid total organic carbon analyzer, a total dissolved solids sensor, a pH meter, and a temperature sensor. The wastewater containing organic fluorine is then introduced into the suspended solids treatment tank, organic matter treatment tank, high salinity treatment tank, acid-base treatment tank, and heat exchanger in the water treatment unit. If any one of the indicators exceeds the standard, it is selectively introduced into the corresponding treatment tank. Step 4: After the organic fluorine-containing wastewater is treated in the pretreatment unit, it continues to be introduced into the perfluorinated and polyfluoroalkyl substances separation unit. Depending on the chain length and treatment target, it is selectively introduced into the short-chain treatment unit, long-chain treatment unit, or comprehensive treatment unit for further treatment. The treated organic fluorine-containing wastewater is discharged after meeting the standards. If it does not meet the standards, the adsorption, oxidation, and / or filtration time and / or reagent dosage and / or treatment time are adjusted by the parameter control module in the parameter setting and control unit. Step 5: After the regeneration control module in the parameter setting and control unit detects that the activated carbon and / or cyclodextrin polymer in the three units of the perfluorinated and polyfluoroalkyl substances separation unit is saturated, it transports the activated carbon and / or cyclodextrin polymer in the perfluorinated and polyfluoroalkyl substances separation unit to the regeneration unit for regeneration. The regenerated activated carbon and / or cyclodextrin polymer are then transported back to the corresponding dosing device in the perfluorinated and polyfluoroalkyl substances separation unit for continued use.

[0050] Furthermore, the scenario database module in step 1 includes at least the following standards: drinking water quality standards (GB5749-2022), surface water quality standards (GB 3838-2002), groundwater quality standards (GB / T 14848-2017), wastewater discharge standards (GB 8978-1996), farmland irrigation water quality standards (GB 5084-2021), fishery water quality standards (GB 11607-1989), landscape and recreational water quality standards (GB 12941-2019), industrial boiler water quality standards (GB / T 1576-2018), the U.S. National Drinking Water Standards, and the European Union Drinking Water Directive.

[0051] Furthermore, in step 2, the sampling and detection frequency in the non-target segment is 5-10 minutes, and the sampling volume per sample is 50-100 mL.

[0052] Furthermore, the detection limit of the target segment in step 2 is 1-2 ng / L, and the detection accuracy is <15-25%.

[0053] This invention provides an application of the treatment system for wastewater containing organic fluoride, which can be applied to drinking water, surface water, groundwater, medical wastewater, industrial wastewater, electroplating / semiconductor industry wastewater, or landfill leachate.

[0054] The beneficial effects of this invention are: This invention utilizes multiple different incoming water detection and pretreatment units, along with parameter settings and control units, to control the treatment tanks, perfluorinated and polyfluoroalkyl substances (PFAS) separation units, and regeneration units within the pretreatment units. This achieves a complete treatment chain encompassing "intelligent detection - on-demand startup - dynamic adaptation - precise treatment - resource recycling - modular integration." When no target PFAS is detected in the incoming water or the PFAS concentration is within acceptable limits, the incoming water is directed to the pretreatment unit. When target PFAS is detected in the incoming water and the concentration exceeds the limit, the water enters the PFAS separation unit, achieving on-demand startup with "zero chemical consumption and zero energy consumption." The PFAS separation unit mainly consists of three units: short-chain, long-chain, and comprehensive treatment. For different water qualities, the pretreatment unit first removes high concentrations of suspended solids, dissolved organic matter, and soluble solids from the incoming water, ensuring that subsequent core processes such as PFAS adsorption, oxidation, and membrane separation can efficiently target PFAS, avoiding problems such as "decreased treatment efficiency, equipment contamination, and increased operating costs" caused by insufficient pretreatment. The perfluorinated and polyfluoroalkyl substances separation unit can intelligently trigger the corresponding treatment process according to the concentration, type and treatment target of PFAS in the incoming water, and adjust the process parameters in real time based on the detection results to maximize the treatment efficiency.

[0055] Each unit in this invention complements the others, rather than being a simple combination. First, the incoming water is tested to determine the content and type of PFAS in the water. Based on the detected data, it is determined whether to proceed with the next step of the PFAS treatment unit. Although the pretreatment unit is the basic treatment for wastewater containing organic fluoride, if only the wastewater containing organic fluoride is treated by the PFAS treatment unit, it will inevitably lead to problems such as decreased treatment efficiency and substandard effluent. Moreover, the pretreatment unit also removes organic matter with CF bonds that are not PFAS. This improves the treatment efficiency of the PFAS treatment unit and also improves the water quality standard at the effluent. The treatment standard can be adjusted according to the needs, which can also reduce energy consumption and chemical dosage, thus improving treatment efficiency and standards while saving energy. Attached Figure Description

[0056] Figure 1 This is a schematic diagram of the connection structure of the treatment system for wastewater containing organic fluoride. Figure 2 This is a schematic diagram of the connection structure of the preprocessing unit; Figure 3 This is a schematic diagram of the connection structure of the incoming water detection unit; Figure 4 This is a schematic diagram of the connection structure of the preprocessing unit; Figure 5 This is a schematic diagram of the connection structure of each device in the preprocessing unit; Figure 6This is a schematic diagram of the connection structure of the separation unit for perfluorinated and polyfluoroalkyl substances. The labels and names in the diagram are as follows: 1. Parameter setting and control unit; 2. Pretreatment unit; 3. Incoming water detection unit; 4. Pretreatment unit; 5. Perfluorinated and polyfluoroalkyl substances separation unit; 6. Regeneration unit; 7. Mechanical unit; 21. Filtration device; 22. Adjustment device; 31. Non-targeted section; 32. Targeted section; 41. Water quality detection unit; 42. Water quality treatment unit; 411. Turbidity sensor; 412. Total organic carbon rapid analyzer; 413. Total dissolved solids sensor; 414. pH meter; 415. Temperature sensor; 421. Suspended solids treatment tank; 422. Organic matter treatment tank; 423. High salinity treatment tank; 424. Acid-base treatment tank; 425. Heat exchanger; 51. Short-chain treatment unit; 52. Long-chain treatment unit; 53. Comprehensive treatment unit. Detailed Implementation

[0057] The invention will be described in detail below with reference to the embodiments: This invention provides a treatment system, method, and application for wastewater containing organofluorine compounds. By first testing the incoming water, wastewater with different pollutants is selectively transported to the corresponding unit for treatment. The system includes units for treating perfluorinated and polyfluoroalkyl substances with different chain lengths, enabling treatment to meet different standards. It is energy-saving, easy to operate, and has a wide range of applications.

[0058] Example 1 This embodiment provides a treatment system for wastewater containing organic fluorine, which includes a parameter setting and control unit 1, a pretreatment unit 2, an incoming water detection unit 3, a pretreatment unit 4, a perfluorinated and polyfluoroalkyl substances (PFAS) separation and treatment unit 5, a regeneration unit 6, and a mechanical unit 7. The parameter setting and control unit 1 is connected to the pretreatment unit 2, the incoming water detection unit 3, the pretreatment unit 4, the perfluorinated and polyfluoroalkyl substances separation unit 5, and the regeneration unit 6. The pretreatment unit 2 is connected in series with the incoming water detection unit 3; The incoming water detection unit 3 is connected in parallel with the pretreatment unit 4; The pretreatment unit 4 is connected in series with the perfluorinated and polyfluoroalkyl substances separation unit 5; The regeneration unit 6 is cyclically connected to the perfluorinated and polyfluoroalkyl substances separation unit 5; The parameter setting and control unit 1, the pretreatment unit 2, the incoming water detection unit 3, the pretreatment unit 4, the perfluorinated and polyfluoroalkyl substances separation unit 5, and the regeneration unit 6 are all fixed on the mechanical unit 7; The detection limit range for perfluorinated and polyfluoroalkyl substances in the wastewater containing organofluorine by the treatment system is ng-mg / L, and the lowest detection limit is 1-2ng / L. The chain length of the perfluorinated and polyfluoroalkyl substances detected is C2-C20.

[0059] The proposed detection limit range for perfluorinated and polyfluoroalkyl substances addresses the issues of high-concentration matrix suppressing low-concentration detection signals and the inability of low-concentration detection modes to tolerate high-concentration pollution. It also solves the problem that existing PFAS detection limits are mostly between 5-10 ng / L. Short-chain PFAS, due to their small molecular size and weak hydrophobicity, are prone to problems such as "adsorption loss, low separation efficiency, and weak detection signals" in traditional detection methods. The high-resolution characteristics of the non-targeted HRMS instrument in the incoming water detection unit, combined with the multi-reaction monitoring mode of the targeted triple quadrupole mass spectrometer, and the design of dedicated detection ion pairs for short-chain PFAS, avoid overlap of mass spectrometric peaks between short-chain PFAS and other small molecules in wastewater. Simultaneously, a minimum detection limit of 1 ng / L is set, enabling precise capture of trace short-chain PFAS in the environment. This precisely matches the processing capacity of the perfluorinated and polyfluoroalkyl substance separation unit, ensuring accurate detection data for wastewater with varying degrees of pollution.

[0060] In this embodiment, the parameter setting and control unit 1 includes a scene database module, a parameter adjustment module, an operation monitoring module, and a regeneration control module.

[0061] The scenario database module includes at least the following standards: drinking water quality standards (GB 5749-2022), surface water quality standards (GB 3838-2002), groundwater quality standards (GB / T 14848-2017), wastewater discharge standards (GB 8978-1996), farmland irrigation water quality standards (GB 5084-2021), fishery water quality standards (GB 11607-1989), landscape and recreational water quality standards (GB 12941-2019), industrial boiler water quality standards (GB / T 1576-2018), the US National Drinking Water Standards, and the EU Drinking Water Directive.

[0062] The parameter setting and control unit 1, based on the water quality standards in the scenario database module, sets a program through the parameter control module. Combined with the various indicators of the organic fluoride-containing wastewater detected by the operation monitoring module in the influent detection unit 3 and the pretreatment unit 4, the parameter control module sets specific treatment programs for the pretreatment unit 4 and the perfluorinated and polyfluoroalkyl substances separation unit 5 to treat the organic fluoride-containing wastewater to meet the water quality standards specified in the scenario database module. During the treatment process, the operation monitoring module continuously monitors the effluent water quality of each unit, and adjusts the parameters for organic fluoride-containing wastewater that does not meet the water quality standards in the scenario database module. After the adsorption activated carbon in the perfluorinated and polyfluoroalkyl substances separation unit 5 becomes saturated, the regeneration unit 6 regenerates the activated carbon in situ without stopping the water treatment process. The entire process is highly efficient and intelligent.

[0063] The operation monitoring module in the parameter setting and control unit 1 converts the detection data into "digital signals" and connects to the parameter control module. Through the data acquisition card, it converts the analog signal of the incoming water detection unit 3 into a digital signal to ensure data real-time performance; it also automatically removes abnormal data to ensure the accuracy of the data transmitted to the control unit.

[0064] The pretreatment unit 2 includes a filtration device 21 and an adjustment device 22 in sequence according to the direction of sewage flow. The filtration device 21 is a filter needle tube and is equipped with a polyethersulfone filter membrane with a pore size of 0.3-0.5 μm. The adjustment device 22 is equipped with HCl and NaOH dosing devices to adjust the pH of the sewage to 6-8. The pretreatment unit 2 is used to perform preliminary filtration and treatment on sewage containing organic fluoride to ensure the detection accuracy of the incoming water detection unit 3.

[0065] The incoming water detection unit 3 includes a non-target section 31 and a target section 32 in sequence according to the direction of sewage flow. The sampling port of the non-target section 31 is equipped with an automatic sampling valve. The material of the automatic sampling valve is polyethylene or polyvinyl chloride to avoid secondary pollution of PFAS. The sampling frequency of the non-target section 31 is 5-10 min, and the single sampling volume is 50-100 mL.

[0066] A high-resolution time-of-flight mass spectrometer (HRMS) is installed in the non-target segment 31. The HRMS is used for preliminary qualitative and quantitative analysis of perfluorinated and polyfluoroalkyl substances. The HRMS is used to preliminarily detect whether the organic fluorine-containing wastewater contains perfluorinated and polyfluoroalkyl substances with CF bonds, and to preliminarily determine the total amount of CF bonds in the organic fluorine-containing wastewater. The detection time is ≤30s.

[0067] The targeted segment 32 is equipped with a triple quadrupole mass spectrometer, which is used for the precise quantification of perfluorinated and polyfluoroalkyl substances (PFAS) and the analysis of their types. The triple quadrupole mass spectrometer is used to accurately analyze the content of PFAS in the organofluorine-containing wastewater, the chain length of the alkyl groups in the PFAS, and the distribution of their structural components. The detection limit of the triple quadrupole mass spectrometer is set to 1-2 ng / L, and the detection accuracy is <15-25%. Similarly, the triple quadrupole mass spectrometer can accurately quantify and analyze the structure of more than 80 PFAS.

[0068] The device in the non-targeting segment 31 is used to detect the total amount of CF bonds in organofluorine wastewater. However, not all substances containing CF bonds are perfluorinated and polyfluoroalkyl substances (PFAS). The device in the targeting segment 32 is then used to accurately analyze the corresponding substances of CF bonds in organofluorine wastewater. This allows for precise analysis of the specific types, chain lengths, and corresponding contents of perfluorinated and polyfluoroalkyl substances (PFAS) in the wastewater. This facilitates targeted treatment of different types of perfluorinated and polyfluoroalkyl substances (PFAS) and the detection of perfluorinated and polyfluoroalkyl substances (PFAS) in the treated wastewater to obtain the removal rate of perfluorinated and polyfluoroalkyl substances (PFAS) with different chain lengths.

[0069] The data detected in the non-targeted and targeted segments of the incoming water detection unit 3 are transmitted to the operation monitoring module in the parameter setting and control unit 1 via a signal line. The adsorption time and chemical treatment time required in the subsequent perfluorinated and polyfluoroalkyl substances separation unit 5 are precisely set by the parameter control module based on the water quality standards set by the scenario database module.

[0070] The pretreatment unit 4 includes, in sequence according to the direction of wastewater flow, a water quality detection unit 41 and a water quality treatment unit 42. The water quality detection unit 41 includes, in sequence according to the direction of wastewater flow, at least a turbidity sensor 411, a total organic carbon (TOC) rapid analyzer 412, a total dissolved solids (TDS) sensor 413, a pH meter 414, and a temperature sensor 415. The water quality treatment unit 42 corresponds to the water quality detection unit 41 and includes, in sequence according to the direction of wastewater flow, at least a suspended solids treatment tank 421, an organic matter treatment tank 422, a high salinity treatment tank 423, an acid-base treatment tank 424, and a heat exchanger 425.

[0071] The suspended solids treatment tank includes a clarification tank and a sand filter tank in sequence; the organic matter treatment tank includes an activated carbon adsorption tank and an ozone tank in sequence; the high saline treatment tank contains a cation exchange column; the acid-base treatment tank is divided into an alkali tank and an acid tank, wherein the alkali in the alkali tank is NaOH and the acid tank is HCl, and the pH of the treated water is 6-8; the temperature of the water after heat exchange in the heat exchanger is 20-30℃.

[0072] In the organic matter treatment tank, when the total organic matter content is >1μg / L, an ozone tank is used for treatment; when the total organic matter content is <1μg / L, an activated carbon adsorption tank is used for treatment.

[0073] The operation monitoring module in the parameter setting and control unit 1 uses the data detected by the water quality detection unit 41 to select whether wastewater containing organic fluoride should pass through the various devices in the water quality treatment unit 42, and then adjusts the degree of treatment through the parameter control module.

[0074] The perfluorinated and polyfluoroalkyl substances separation unit 5 includes a short-chain processing unit 51, a long-chain processing unit 52, and a comprehensive processing unit 53.

[0075] The short-chain treatment unit 51 is used to remove perfluorinated and polyfluoroalkyl substances with chain lengths of C2-C7, specifically perfluorinated and polyfluoroalkyl carboxylic acids with chain lengths of C2-C7 or perfluorinated and polyfluoroalkyl sulfonic acids with chain lengths of C2-C5. The short-chain treatment unit 51 includes a cyclodextrin polymer dosing device, an oxidant dosing device, and a strongly basic anion exchange column.

[0076] The short-chain processing unit 51 achieves a removal rate of ≥99% for perfluorinated and polyfluoroalkyl substances with chain lengths of C4-C6.

[0077] The short-chain treatment unit 51 also includes an electrochemical catalytic device or a photocatalytic device for treating wastewater containing organic fluorine that still does not meet the standards after treatment by the cyclodextrin polymer dosing device, oxidant dosing device, and ion exchange column.

[0078] The short-chain treatment unit 51 first adds the cyclodextrin polymer and / or oxidant to the organic fluoride-containing wastewater, and then passes it through the strongly alkaline anion exchange column. If it still does not meet the water quality standards of the scenario database module, it continues to be treated by an electrochemical catalytic device or a photocatalytic device.

[0079] The long-chain treatment unit 52 is used to remove perfluorinated and polyfluoroalkyl substances with chain lengths of C6-C20, specifically perfluorinated and polyfluoroalkyl carboxylic acids or perfluorinated and polyfluoroalkyl sulfonic acids with chain lengths of C8-C20. The long-chain treatment unit 52 includes an activated carbon dosing device, an oxidant dosing device, a strong base anion exchange column, and a ceramic membrane ultrafiltration device.

[0080] The long-chain treatment unit 52, consisting of activated carbon, oxidant, ion exchange column, and ceramic membrane ultrafiltration device, achieves a removal rate of 80-90% for long-chain perfluorinated and polyfluoroalkyl substances.

[0081] The long-chain treatment unit 52 first adds activated carbon and / or oxidant to the organic fluoride wastewater, then passes it through the strongly alkaline anion exchange column, and then continues to be treated through the ceramic membrane ultrafiltration device.

[0082] The integrated treatment unit 53 is used to remove C2-C20 chain length perfluorinated and polyfluoroalkyl substances. The integrated treatment unit 53 includes an activated carbon dosing device, an oxidant dosing device, a strong base anion exchange column, a ceramic membrane ultrafiltration device, and a nanofiltration / reverse osmosis device.

[0083] The wastewater containing organic fluoride in the integrated treatment unit 53 is first treated with activated carbon and / or oxidant, then passed through the strongly alkaline anion exchange column, then through the ceramic membrane ultrafiltration device for ultrafiltration, and finally through the nanofiltration / reverse osmosis device for further treatment.

[0084] When the water quality standard set by the scenario database module in the parameter setting and control unit 1 is met (the content of perfluorinated and polyfluoroalkyl substances is <100ng / L), the standard can be achieved by using the cyclodextrin polymer / activated carbon adsorption and oxidant oxidation in the short-chain treatment unit 51, the long-chain treatment unit 52, or the comprehensive treatment unit 53. At the same time, the parameters such as the adsorption time of the cyclodextrin polymer / activated carbon, the dosage of the oxidant, and the ultrafiltration membrane pressure during ultrafiltration are controlled by the operation monitoring module.

[0085] When the operation monitoring module in the parameter setting and control unit 1 detects that the content of perfluorinated and polyfluoroalkyl substances in the treated organic fluoride-containing wastewater of the short-chain treatment unit 51, the long-chain treatment unit 52, or the comprehensive treatment unit 53 is greater than 80% of the target value, the parameter control module automatically extends the adsorption time, increases the oxidant content, etc.; or when the content of perfluorinated and polyfluoroalkyl substances in the treated organic fluoride-containing wastewater is less than 50% of the target value, the parameter control module automatically reduces the oxidant content or reduces the adsorption time, etc.

[0086] The regeneration unit 6 includes an activated carbon regeneration device, which can be an in-situ regeneration device or a non-in-situ regeneration device, and the activated carbon regeneration device performs thermal regeneration or solvent regeneration on the activated carbon.

[0087] The regeneration control module in the parameter setting and control unit 1 detects that the activated carbon and / or cyclodextrin polymer in the three units of the perfluorinated and polyfluoroalkyl substances separation unit 5 is saturated. Then, it transports the activated carbon and / or cyclodextrin polymer in the perfluorinated and polyfluoroalkyl substances separation unit 5 to the regeneration unit 6. Regeneration is carried out by heating and desorption at 200-300°C followed by inert gas purging, or by washing with sodium hydroxide or methanol. The regenerated activated carbon and / or cyclodextrin polymer are then transported back to the corresponding dosing device in the perfluorinated and polyfluoroalkyl substances separation unit 5 for continued use.

[0088] The regeneration control module in the parameter setting and control unit 1 detects that the content of perfluorinated and polyfluoroalkyl substances adsorbed by activated carbon and / or cyclodextrin polymer in the three units of the perfluorinated and polyfluoroalkyl substances separation unit 5 is greater than 20% of the content at the inlet of the perfluorinated and polyfluoroalkyl substances separation unit 5, and then starts the regeneration unit 6 for regeneration.

[0089] The mechanical unit 7 is a box-type structure. The parameter setting and control unit 1, the pretreatment unit 2, the incoming water detection unit 3, the pretreatment unit 4, the perfluorinated and polyfluoroalkyl substances separation unit 5, and the regeneration unit 6 are all fixed in the box-type structure of the mechanical unit 7 by bolts. The devices of each unit are connected by pipes, flanges, and sealing rings.

[0090] The bottom of the box-shaped structure of the mechanical unit 7 is equipped with pulleys for easy movement of the mechanical unit 7.

[0091] Example 2 This embodiment provides a treatment method for a wastewater treatment system containing organic fluoride, including the following steps: Step 1: Before treating wastewater containing organic fluoride, first set the water quality standards for treatment through parameter settings and the scenario database module in control unit 1; Step 2: The wastewater containing organic fluoride is introduced into the pretreatment unit 2. It is first filtered through a 0.45μm polyethersulfone membrane in the filter tank 21. Then, acid or alkali is added to the equalization tank 22 to adjust the pH of the wastewater containing organic fluoride to 6-8. After adjustment, it is directly introduced into the non-targeted section 31 and the targeted section 32 of the incoming water detection unit 3. The wastewater in the non-targeted section 31 is sampled at a sampling frequency of 5 minutes and the sampling volume is 50 mL to determine the total amount and content of different types of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluoride. Step 3: After quantitative and qualitative analysis of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluorine, it is introduced into the pretreatment unit 4. The wastewater is measured by a turbidity sensor 411, a total organic carbon rapid analyzer 412, a total dissolved solids sensor 413, a pH meter 414, and a temperature sensor 415. When the turbidity of the wastewater containing organic fluorine is >5 NTU, the organic matter content is >0.5 μg / L, the total dissolved solids content is >100 mg / L, the pH range is not 6-8, and the temperature range is not 20-30℃, the wastewater containing organic fluorine is introduced into the suspended solids treatment tank 421, the organic matter treatment tank 422, the high salinity treatment tank 423, the acid-base treatment tank 424, and the heat exchanger 425 in the water treatment unit 42. When any one of the indicators exceeds the standard, the wastewater is selectively introduced into the corresponding treatment tank. Step 4: After the organic fluoride-containing wastewater is treated in the pretreatment unit, it continues to be introduced into the perfluorinated and polyfluoroalkyl substances separation unit 5. Depending on the chain length and treatment target, it is selectively introduced into the short-chain treatment unit 51, the long-chain treatment unit 52, or the comprehensive treatment unit 53 for further treatment. The treated organic fluoride-containing wastewater is discharged after meeting the standards. If it does not meet the standards, the adsorption, oxidation, and / or filtration time and / or reagent dosage and / or treatment time are adjusted by the parameter control module in the parameter setting and control unit 1. Step 5: After the regeneration control module in the parameter setting and control unit 1 detects that the activated carbon and / or cyclodextrin polymer in the three units of the perfluorinated and polyfluoroalkyl substances separation unit 5 is saturated, the activated carbon and / or cyclodextrin polymer in the perfluorinated and polyfluoroalkyl substances separation unit 5 is transported to the regeneration unit 6 and regenerated by heating and desorption at 200-300°C followed by inert gas purging, or by washing with sodium hydroxide or methanol. The regenerated activated carbon and / or cyclodextrin polymer are then transported back to the corresponding dosing device in the perfluorinated and polyfluoroalkyl substances separation unit 5 for continued use.

[0092] As can be seen from the above, the treatment system and method for wastewater containing organofluorine described in this invention have a wide range of applications, low cost, and extremely high market prospects.

[0093] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any modifications or equivalent changes made based on the technical essence of the present invention shall still fall within the scope of protection claimed by the present invention.

Claims

1. A treatment system for wastewater containing organofluorine compounds, characterized in that, The treatment system for wastewater containing organic fluorine includes a parameter setting and control unit (1), a pretreatment unit (2), an incoming water detection unit (3), a pretreatment unit (4), a perfluorinated and polyfluoroalkyl substances separation unit (5), a regeneration unit (6), and a mechanical unit (7). The parameter setting and control unit (1) is connected to the pretreatment unit (2), the incoming water detection unit (3), the pretreatment unit (4), the perfluorinated and polyfluoroalkyl substances separation unit (5), and the regeneration unit (6); The pretreatment unit (2) is connected in series with the incoming water detection unit (3); The incoming water detection unit (3) is connected in parallel with the pretreatment unit (4); The pretreatment unit (4) is connected in series with the perfluorinated and polyfluoroalkyl substances separation unit (5); The regeneration unit (6) is cyclically connected to the perfluorinated and polyfluoroalkyl substances separation unit (5); The parameter setting and control unit (1), the pretreatment unit (2), the incoming water detection unit (3), the pretreatment unit (4), the perfluorinated and polyfluoroalkyl substances separation unit (5), and the regeneration unit (6) are all fixed on the mechanical unit (7); The detection limit range for perfluorinated and polyfluoroalkyl substances in the wastewater containing organofluorine by the treatment system is ng-mg / L, and the lowest detection limit is 1-2ng / L. The chain length of the perfluorinated and polyfluoroalkyl substances detected is C2-C20.

2. The treatment system for wastewater containing organofluorine compounds according to claim 1, characterized in that, The parameter setting and control unit (1) includes a scene database module, a parameter adjustment module, an operation monitoring module, and a regeneration control module.

3. The treatment system for wastewater containing organic fluoride according to claim 1, characterized in that, The pretreatment unit (2) includes a filtration device (21) and a regulating device (22) in sequence according to the direction of sewage flow.

4. The treatment system for wastewater containing organic fluoride according to claim 1, characterized in that, The incoming water detection unit (3) includes a non-target section (31) and a target section (32) in sequence according to the direction of sewage flow.

5. The treatment system for wastewater containing organic fluoride according to claim 1, characterized in that, The pretreatment unit (4) includes a water quality detection unit (41) and a water quality treatment unit (42) in sequence according to the direction of sewage flow.

6. The treatment system for wastewater containing organic fluoride according to claim 1, characterized in that, The perfluorinated and polyfluoroalkyl substances separation unit (5) includes a short-chain processing unit (51), a long-chain processing unit (52), and a comprehensive processing unit (53).

7. The treatment system for wastewater containing organofluorine compounds according to claim 1, characterized in that, The bottom of the box-shaped structure of the mechanical unit (7) is equipped with pulleys for the mechanical unit (7) to move at any time.

8. A treatment method for a wastewater treatment system containing organofluorine compounds as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Before treating wastewater containing organic fluoride, first set the water quality standards for treatment through the scenario database module in the parameter setting and control unit (1); Step 2: After pretreatment, the wastewater containing organic fluorine is directly fed into the non-targeted section (31) and the targeted section (32) of the incoming water detection unit (3) to determine the total amount and content of different types of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluorine. Step 3: After quantitative and qualitative analysis of perfluorinated and polyfluoroalkyl substances in the wastewater containing organic fluorine, it is introduced into the pretreatment unit (4) and measured by turbidity sensor (411), total organic carbon rapid analyzer (412), total dissolved solids sensor (413), pH meter (414) and temperature sensor (415). The wastewater containing organic fluorine is introduced into the suspended solids treatment tank (421), organic matter treatment tank (422), high salinity treatment tank (423), acid and alkali treatment tank (424) and heat exchanger (425) in the water quality treatment unit (42), and selectively introduced into the corresponding treatment tank when one of the indicators exceeds the standard. Step 4: After the organic fluoride-containing wastewater is treated in the pretreatment unit, it continues to be introduced into the perfluorinated and polyfluoroalkyl substances separation unit (5). Depending on the chain length and treatment target, it is selectively introduced into the short chain treatment unit (51), the long chain treatment unit (52), or the comprehensive treatment unit (53) for treatment. The treated organic fluoride-containing wastewater is discharged after meeting the standards. If it does not meet the standards, the adsorption, oxidation and / or filtration time and / or reagent dosage and / or treatment time are adjusted by the parameters in the parameter setting and control unit (1). Step 5: After the regeneration control module in the parameter setting and control unit (1) detects that the activated carbon and / or cyclodextrin polymer in the three units of the perfluorinated and polyfluoroalkyl substances separation unit (5) is saturated, it transports the activated carbon and / or cyclodextrin polymer in the perfluorinated and polyfluoroalkyl substances separation unit (5) to the regeneration unit (6) for regeneration. The regenerated activated carbon and / or cyclodextrin polymer is then transported back to the corresponding dosing device in the perfluorinated and polyfluoroalkyl substances separation unit (5) for continued use.

9. The processing method according to claim 8, characterized in that, The detection limit of the target segment in step 2 is 1-2 ng / L, and the detection accuracy is <15-25%.

10. The application of the treatment system for wastewater containing organofluorine compounds as described in any one of claims 1-7, characterized in that, The treatment system for wastewater containing organic fluoride can be applied to drinking water, surface water, groundwater, medical wastewater, industrial wastewater, electroplating / semiconductor industry wastewater, or landfill leachate.

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