PFAS TREATMENT PROCESS FOR LIQUID EFFLUENT

Abstract

A method for controlling for PFAS removal from a liquid effluent by a control system (100), the control system including a PFAS treatment unit (10) dedicated to the treatment of perfluoroalkyls and polyfluoroalkyl substances PFAS including at least one treatment stage optionally chosen from a PFAS treatment stage, a short chain PFAS treatment stage and a long chain PFAS treatment stage. The method allows activating the PFAS treatment unit only when PFAS, in particular specific PFAS, are detected into the liquid effluent to treat. A control system (100) to implement the method is also disclosed.

Claims

1. A control system for PFAS removal from a liquid effluent comprising: a PFAS treatment unit dedicated to the removal of perfluoroalkyls and polyfluoroalkyl substances PFAS, said PFAS treatment unit including at least one treatment stage chosen from a short and long chain PFAS dedicated treatment stage, a short chain PFAS dedicated treatment stage and a long chain PFAS dedicated treatment stage, where : long-chain PFAS refer to perfluoroalkyl carboxylic acids with eight or more carbons, to perfluoroalkane sulfonates with six or more carbons, and for all the other perfluoroalkyls and polyfluoroalkyl substances to PFAS having a carbon chain with six or more carbon atoms, short-chain PFAS refer to perfluoroalkyl carboxylic acids with seven or fewer carbons and to perfluoroalkane sulfonates with five or fewer carbons, and for all the other perfluoroalkyls and polyfluoroalkyl substances to PFAS having a carbon chain with five or less carbon atoms, a control unit configured to: provide information data representative of the presence or absence of PFAS in liquid effluent to treat, generate at least one activating signal for activating the PFAS treatment unit when the provided information data indicate the presence of PFAS chosen from short chain PFAS, long chain PFAS and short and long chain PFAS, this signal being chosen from: a signal for activating said at least one short and long chain PFAS dedicated treatment stage when the provided information data include information data representative of the presence of at least one PFAS chosen from short chain PFAS, long chain PFAS and short and long chain PFAS, a signal for activating said at least one short chain PFAS dedicated treatment stage when the provided information data include information data representative of the presence of at least one short chain PFAS, and a signal for activating at least one long chain PFAS dedicated treatment stage when the provided information data include information data representative of the presence of at least one long chain PFAS, transmit said at least one activating signal to the PFAS treatment unit to activate the PFAS treatment unit, optionally the corresponding at least one PFAS treatment stage chosen from a short and long chain PFAS dedicated treatment stage, a short chain PFAS dedicated treatment stage and a long chain PFAS dedicated treatment stage, to remove from the liquid effluent to treat at least a part of the PFAS.

2. The control system as claimed in claim 1, wherein the control unit is configured to provide information data by: determining information data of the raw water chosen among one or several of the following data: data representative of the presence of carbon-fluorine bonds, data representative of the presence of fluorine, data representative of the chemical formula of at least one PFAS, data representative of the concentration of at least one PFAS, data representative of the absence of PFAS and data representative of an estimated total concentration of targeted PFAS.

3. The control system as claimed in claim 1, wherein the control unit is configured to provide information data by: (i) determining at least one information data representative of the chemical formula of at least one PFAS present in the liquid effluent, (ii) providing information data representative of the presence of PFAS, comprising: identifying targeted PFAS present in the liquid effluent by comparing the received at least one information data representative of the chemical formula with a registered list of targeted PFAS, this list including the chemical formulas of targeted short chain PFAS, targeted long chain PFAS, or both, optionally providing concentration data representative of the concentration in the liquid effluent of the identified targeted PFAS, providing information data representative of the presence of the identified targeted PFAS, in particular the presence of short chain targeted PFAS, long chain targeted PFAS or both, and optionally of their concentration.

4. The control system as claimed in claim 1 further comprising a pilot unit (80) configured to control operating conditions of the PFAS treatment unit as a function of one or several parameters chosen among identified PFAS, PFAS concentration, efficiency of the removal, other pollutants contained in the liquid effluent to treat.

5. The control system as claimed in claim 1, wherein the PFAS treatment unit comprises at least one of the following features: at least one vessel to implement said at least one treatment stage, optionally chosen from the short and long chain dedicated treatment stage, the short chain PFAS dedicated treatment stage and the long chain PFAS dedicated treatment stage, at least two vessels in series and/or in parallel, at least one vessel dedicated to at least one treatment stage, optionally a short chain PFA dedicated treatment stage, and at least another vessel dedicated to at least one other treatment stage, optionally a long chain PFA dedicated treatment stage.

6. The control system as claimed in claim 1, wherein the PFAS treatment unitcomprises at least one reagent dedicated to remove the PFAS by ionic exchange, adsorption or both, said reagent being chosen among a reagent dedicated to remove long chain PFAS, a reagent dedicated to remove short chain PFAS and a reagent dedicated to remove short and long chain PFAS, preferably among the two first cited reagents, said at least one reagent being preferably in granular or powder form.

7. The control system as claimed in claim 6, wherein the at least one reagent dedicated to remove PFAS is chosen from: a cyclodextrin polymer, in particular a porous cyclodextrin polymer, supported or not on a solid substrate, activated carbon, in particular granulated or powdered activated carbon, organoclays, in particular positively charged, inorganic-organic clays, in particular positively charged, anion exchange resins, in particular strongly basic anion exchange resins, biochar or activated biochar.

8. The control system as claimed in claim 1, further comprising: an analysis unit including at least one apparatus for performing a non targeted analysis of the liquid effluent to treat, and generating information chosen among one or several of the following data : data representative of the presence of carbon-fluorine bonds, data representative of the presence of fluorine, data representative of the chemical formula of at least one PFAS present in the liquid effluent to treat, in particular of all the PFAS present, and data representative of an estimated total concentration of targeted PFAS, optionally at least one apparatus for performing a targeted analysis of the liquid effluent to treat and generating information data representative of the concentration of PFAS identified in the liquid effluent.

9. A method for controlling removal of perfluoroalkyl and polyfluoroalkyl substances PFAS from a liquid effluent by means of a control system including a PFAS treatment unit dedicated to the treatment of PFAS including at least one treatment stage chosen from a short and long chain PFAS dedicated treatment stage, a short chain PFAS dedicated treatment stage and a long chain PFAS dedicated treatment stage, where long-chain PFAS refer to perfluoroalkyl carboxylic acids with eight or more carbons and to perfluoroalkane sulfonates with six or more carbons, and for all the other perfluoroalkyls and polyfluoroalkyl substances to PFAS having a carbon chain with six or more carbon atoms, short-chain PFAS refer to perfluoroalkyl carboxylic acids with seven or fewer carbons and to perfluoroalkane sulfonates with five or fewer carbons, and for all the other perfluoroalkyls and polyfluoroalkyl substances to PFAS having a carbon chain with five or less carbon atoms, the method comprising: (A)providing information data representative of the presence or absence of PFAS in a liquid effluent to treat, (B) generating at least one activating signal for activating the PFAS treatment unit when the provided information data indicate the presence of PFAS chosen from short chain PFAS, long chain PFAS and short and long chain PFAS, said at least one activating signal being this signal being chosen from : a signal for activating said at least one short and long chain PFAS dedicated treatment stage when the provided information data includes information data representative of the presence of at least one PFAS chosen from short chain PFAS, long chain PFAS and short and long chain PFAS, a signal for activating said at least one short chain PFAS dedicated treatment stage when the provided information data include information data representative of the presence of at least one short chain PFAS, and a signal for activating said at least one long chain PFAS dedicated treatment stage when the provided information data include information data representative of the presence of at least one long chain PFAS, (C) transmitting said at least one activating signal to the PFAS treatment unit to activate said at least one treatment stage of the PFAS treatment unit, optionally to activate the corresponding at least one PFAS treatment stage chosen from a short and long chain PFAS dedicated treatment stage, a short chain PFAS dedicated treatment stage and a long chain PFAS dedicated treatment stage, to remove at least a part of the PFAS from the liquid effluent.

10. The method as claimed in claim 9, wherein the step for providing information data includes: determining information data of the liquid effluent chosen among one or several of the following data: data representative of the presence of carbon-fluorine bonds, data representative of the presence of fluorine, data representative of the chemical formula of at least one PFAS, data representative of the concentration of at least one PFAS, data representative of the absence of PFAS and data representative of an estimated total concentration of targeted PFAS.

11. The method as claimed in claim 9, wherein, in the step for providing information data includes: (i) determining at least one information data representative of the chemical formula of at least one PFAS present in the liquid effluent, (ii) a step of providing information data representative of the presence of PFAS comprising: identifying targeted PFAS present in the liquid effluent by comparing the received at least one information data representative of the chemical formula with a registered list of targeted PFAS, this list including the chemical formulas of targeted short chain PFAS, targeted long chain PFAS, or both, optionally providing concentration data representative of the concentration in the liquid effluent of the identified targeted PFAS, providing information data representative of the presence of identified targeted PFAS, in particular the presence of short chain targeted PFAS, long chain targeted PFAS or both, and optionally of their concentration.

12. The method as claimed in claim 9, wherein Step for providing information data includes: determining information data of the liquid effluent including data representative of the concentration of at least one PFAS chosen from a short chain PFAS and a long chain PFA, and step includes: generating said at least one signal for activating said at least one short chain PFAS dedicated treatment stage when data representative of the concentration of one or several short chain PFAS are above a first threshold, specific for short chain PFAS, generating said at least one signal for activating said at least one long chain PFAS dedicated treatment stage when data representative of the concentration of one or several long chain PFAS are above a second threshold, specific for long chain PFAS, optionally generating at least one signal for activating said at least one short and long chain PFAS dedicated treatment stage.

13. The method as claimed in claim 9, wherein, once activated, operating conditions of the PFAS treatment unit are controlled as a function of one or several parameters chosen among identified PFAS, PFAS concentration, efficiency of the removal, other pollutants contained in the liquid effluent to treat.

14. The method as claimed in claim 9, wherein, during activation of the PFAS treatment unit, the liquid effluent is submitted to at least one of the following treatments: a treatment in which the liquid effluent is contacted with at least one reagent dedicated to remove the PFAS by ionic exchange, adsorption or both, said reagent being chosen among a reagent dedicated to remove long chain PFAS, a reagent dedicated to remove short chain PFAS and a reagent dedicated to remove short and long chain PFAS, preferably among the two first cited reagents, said at least one reagent being preferably in granular or powder form, a nanofiltration, a reverse osmosis.

15. The method as claimed in claim 14, wherein said at least one reagent dedicated to remove PFAS is chosen from: a cyclodextrin polymer, in particular a porous cyclodextrin polymer, supported or not on a solid substrate, activated carbon, in particular granulated or powdered activated carbon, organoclays, in particular positively charged, inorganic-organic clays, in particular positively charged, anion exchange resins, in particular strongly basic anion exchange resins, biochar or activated biochar.

16. The method as claimed in claim 9, wherein step includes: performing on the liquid effluent to treat a non targeted analysis and generating information data chosen among one or several of the following data: data representative of the presence of carbon-fluorine bonds, data representative of the presence of fluorine, data representative of the chemical formula of at least one PFAS present in the liquid effluent to treat, in particular of all the PFAS present, and data representative of an estimated total concentration of targeted PFAS, optionally: identifying targeted PFAS present in the liquid effluent by comparing the information data generated by the non targeted analysis with a registered list of targeted PFAS, this list including the chemical formulas of targeted short chain PFAS, targeted long chain PFAS, or both, performing on the liquid effluent to treat a targeted analysis and generating information data representative of the concentration of targeted PFAS identified in the liquid effluent.

17. A computer program comprising the instructions for carrying out the steps of the method according to claim 9, when said instructions are executed by one or more processors.

18. A computer-readable medium having stored thereon the computer program of claim 17.

Description

DESCRIPTION OF THE DRAWINGS

[0245] The invention will be better understood with reference to the figures, which show exemplary embodiments of the invention.

[0246] FIG. 1 represents schematically a liquid effluent treatment facility including a control system according to one embodiment.

[0247] FIG. 2 is a flowchart of an embodiment of the method of the invention.

[0248] FIGS. 3 and 4 show adsorbent uptake of different PFAS for different doses of adsorbent and at different contact times.

[0249] On FIG. 1, a liquid effluent treatment facility 1 is represented, here a water treatment facility for producing drinking water from surface water.

[0250] The water treatment facility 1 comprises a PFAS treatment unit 10. It also typically includes a coagulation-flocculation unit 20, a sedimentation or flotation unit 30, a filtration unit 40 and a tank 50.

[0251] The PFAS treatment unit 10 is here mounted in derivation ahead from the filtration unit 40, but could be positioned before or after the coagulation-flocculation unit 20, before or after the sedimentation or flotation unit 30, or as part of the sedimentation or flotation unit 30, or as part of the filtration unit 40.

[0252] The position of the unit 10 within the treatment facility 1 is depending on the reagent configuration within unit 10 when this unit includes a treatment stage by contacting with a reagent.

[0253] For a powdered reagent, unit 10 can be positioned before or after unit 20, or as part of sedimentation or flotation unit 30. For granular reagent, unit 10 can be positioned before or after unit 40 or combined with it when this unit is based on membrane.

[0254] The filtration unit 40 may be a microfiltration or ultrafiltration unit, using organic or ceramic membranes, optionally vacuum driven membranes. The use of the PFAS treatment unit 10 ahead from the filtration unit 40 can be useful to limit the fouling of the membrane and also to enhance the production rate of the filtration unit 40.

[0255] The PFAS treatment unit 10 may also be designed to be a mobile unit that can be connected in derivation at any appropriate point of the water treatment facility 1.

[0256] The PFAS treatment unit 10 includes at least one treatment stage, here a short chain PFAS dedicated treatment stage 101 and a long chain PFAS dedicated treatment stage 102. The invention is of course not limited by the number of treatment stages or their nature. A further short and long chain PFAS dedicated treatment stage may be present.

[0257] Each treatment stage 101, 102 here comprises two vessels respectively 103, 104; 105, 106, which may be mounted in parallel or in series in each stage. Each vessel can be dedicated to nanofiltration, reverse osmosis or reagent contact.

[0258] Vessels adapted for reactant contact can be any reaction stirred chamber or settling tanks, in particular sludge recirculating settling tanks optionally pulsed, or any other conventional settling or flotation tank.

[0259] Reagents to be used for PFAS removal by contact with water are those previously cited with respect to the method for controlling PFAS removal.

[0260] The water treatment facility 1 further includes a control unit 60, in particular for the PFAS treatment unit, but which may also be used to control the other units of the water treatment facility 1. The control unit 60 is adapted to implement the steps of the process of the invention for activating the PFAS treatment unit when appropriate, as well as for controlling its operating conditions once activated, and more specifically to activate the PFAS as long as necessary for PFAS removal. In particular, it can decide that activation is ended when the effluent to treat does not contain any more short and/or long chain PFAS or at a concentration lower than a pre-determined threshold.

[0261] The control unit 60 and the PFAS treatment unit 10 form a control system 100 according to the invention.

[0262] The control unit 60 may comprise receiving means 61, treatment means 62 and transmitting means 63. Receiving means may be input or input/output interfaces, transmitting means may be output or input/output interfaces. They can be wireless communication interfaces (Bluetooth, WIFI or other) or connectors (network port, USB port, serial port, Firewire® port, SCSI port or other). Treatment means may be one or several processors, for example microprocessors or microcontrollers. The processor(s) may have storage means which may be random access memory (RAM), Electrically-Erasable Programmable Read-Only Memory (EEPROM), flash memory, external memory, or other. These storage devices can store, among other things, received data, a targeted list of PFAS, a control model, a data base and computer program(s).

[0263] The water treatment facility 1 here further includes an analysis unit 70 including one apparatus 71 for performing a non targeted analysis and one apparatus 72 for performing a targeted analysis. In the embodiment represented, the water for analysis is taken at the entry of the water treatment facility 1, the invention is however not limited to such position, and the analysis may be performed on water at any stage of the water treatment facility 1.

[0264] A pilot unit 80 is also provided for controlling the PFAS treatment unit 10 once activated. Such pilot unit 80 may receive information data from the control unit 60, in particular information data representative of the chemical formula and concentration of PFAS, in particular of targeted PFAS. Such pilot unit 80 may be one or several processors, for example microprocessors or microcontrollers. The processor(s) may have storage means which may be random access memory (RAM), Electrically-Erasable Programmable Read-Only Memory (EEPROM), flash memory, external memory, or other. These storage devices can store, among other things, received data, a targeted list of PFAS, a control model, a data base and computer program(s). The pilot unit 80 may be incorporated into the control unit 60.

[0265] FIG. 2 is a flowchart of a first embodiment of the present invention.

[0266] STEP 1, there is provided data representative of the presence or absence of PFAS in a liquid effluent to treat. Such information data may result from a non targeted analysis or a targeted analysis.

[0267] In the embodiment represented, a non targeted analysis first screens the PFAS present in the liquid effluent and generates information data representative of the chemical formula of screened PFAS, Chem_data. It should be noted that if no PFAS is present, i.e. if no information data representative of the chemical formula of PFAS is generated, an information data representative of the absence of PFAS is generated and the process goes to STEP 7 and stops, no activated signal is generated.

[0268] The information data representative of the chemical formula of PFAS are for example a molecular mass range of the PFAS obtained by high resolution mass spectrometry analysis. If this molecular mass is in/outside the range of PFAS molecular mass range, then information data representative of the presence/absence of PFAS is generated. If information data representative of the presence of PFAS is generated, the process goes to STEP 2. In STEP 2, these chemical data are compared with a registered list of targeted PFAS, Reg_List. If targeted PFAS are present in Reg_List, a targeted analysis is performed in STEP 3 on these detected targeted PFAS to obtain inlet concentration of each detected targeted PFAS, [Targ.]_data. If no targeted PFAS are identified, the process goes to STEP 7 and stops, no activated signal is generated.

[0269] By way of example, the compounds of the list of Table 1 may be used as a registered list.

TABLE-US-00001 Registered list (Reg_ List) Class Compounds Formule Carbon number CAS # molecular weigth PFCA TFA=Trifluoroacetic acid C.sub.2HF.sub.3O.sub.2 C2 76-05-1 114.02 PFPrA= pentafluoropropionic acid C.sub.3HF.sub.5O.sub.2 C3 422-64-0 164.03 PFBA = perfluorobutyric acid C.sub.4HF.sub.7O.sub.2 C4 375-22-4 214.04 PFPeA = perfluoropentanoic acid C.sub.5HF.sub.9O.sub.2 C5 2706-90-3 264.05 PFHxA = perfluorohexanoic acid C.sub.6HF.sub.11O.sub.2 C6 307-24-4 314.05 PFHpA = perfluoroheptanoic acid C.sub.7HF.sub.13O.sub.2 C7 375-85-9 364.06 PFOA = perfluorooctanoic acid C.sub.8HF.sub.15O.sub.2 C8 335-67-1 414.07 PFNA = perfluorononanoic acid C.sub.9HF.sub.17O.sub.2 C9 375-95-1 500.13 PFDA = perfluorodecanoic acid C.sub.10HF.sub.19O.sub.2 C10 335-76-2 514.08 PFUnDA= Perfluoroundecanoic acid C.sub.11HF.sub.21O.sub.2 C11 2058-94-8 564.09 PFDoA = perfluorododecanoic acid C.sub.12HF.sub.23O.sub.2 C12 307-55-1 614.1 PFTrDA = perfluorotridecanoic acid C.sub.13HF.sub.25O.sub.2 C13 72629-94-8 664.11 PFTeDA = perfluorotetradecanoic acid C.sub.14HF.sub.27O.sub.2 C14 376-06-7 714.11 PFHxDA=Perflurohexadecanoic acid C.sub.16HF.sub.31O.sub.2 C16 67905-19-5 814.13 PFOcDA=perfluorooctadecanoic acid C.sub.18HF.sub.35O.sub.2 C18 16517-11-6 914.14 PFSA TFMS= Trifluoromethanesulfonic acid CF.sub.3SO.sub.3H C1 1493-13-6 150.08 PFEtS=Perfluoroethane sulfonic acid C.sub.2F.sub.5SO.sub.3H C2 354-88-1 200.09 PFPrS=Perfluoropropane sulfonic acid C.sub.3F.sub.7SO.sub.3H C3 423-41-6 250.09 PFBS = perfluorobutane sulfonic acid C.sub.4HF.sub.9O.sub.3S C4 375-73-5 300.1 PFPeS=Perfluoropentane sulfonic acid C.sub.5HF.sub.11O.sub.3S C5 2706-91-4 350.11 PFHxS = perfluorohexane sulfonic acid C.sub.6HF.sub.13O.sub.3S C6 355-46-4 432-50-8 400.11 PFHpS=Perfluoroheptane sulfonic acid C.sub.7HF.sub.15O.sub.3S C7 375-92-8 450.12 PFOS = perfluorooctane sulfonic acid C.sub.8HF.sub.17O.sub.3S C8 1763-23-1 500.13 PFNS=Perfluorononanesulfonic acid C.sub.9HF.sub.19O.sub.3S C9 68259-12-1 550.14 PFDS = perfluorodecane sulfonate C.sub.10HF.sub.21O.sub.3S C10 335-77-3 514.08 PFUnS / PFUnDS=Perfluoroundecane sulfonic acid C.sub.11F.sub.23O.sub.3S C11 749786-16-1 650.15 PFDoDS=Perfluorododecanane sulfonic acid C.sub.12HF.sub.25O.sub.3S C12 79780-39-5 700.16 PFTriS / PFTrDS =Perfluorotridecane sulfonic acid C.sub.13F.sub.27O.sub.3S C13 NAN 749.1 FTS 4:2 FTS= 4:2 Fluorotelomer sulfonate C.sub.6H.sub.5F.sub.9SO.sub.3 C6 757124-72-4 328.15 6:2 FTS = 6:2 Fluorotelomer sulfonate C.sub.8H.sub.5F.sub.13O.sub.3S C8 27619-97-2 428.17 8:2 FTS = 8:2 Fluorotelomer sulfonate C.sub.10H.sub.5F.sub.17SO.sub.3 C10 39108-34-4 528.18 perfluorooctane sulfonic acid derivative FOSAA=perfluorooctane sulfonamidoacetic acid C.sub.10H.sub.4F.sub.17NO.sub.4S C10 2806-24-8 557.18 N-MeFOSAA=N-methyl perfluorooctane sulfonamidoacetic acid C.sub.11H.sub.6F.sub.17NO.sub.4S C11 2355-31-9 571.21 N-EtFOSAA = N-ethyl perfluorooctane sulfonamidoacetic acid C.sub.12H.sub.8F.sub.17NO.sub.4S C12 2991-50-6 585.23 n:2 FTOH 4:2 FTOH= 4:2 Fluorotelomer alcohol C.sub.6H.sub.5F.sub.9O C6 2043-47-2 264.09 6:2 FTOH= 6:2 Fluorotelomer alcohol C.sub.8H.sub.5F.sub.13O C8 647-42-7 364.1 8:2 FTOH= 8:2 Fluorotelomer alcohol C.sub.10H.sub.5F.sub.17O C10 678-39-7 464.12 10:2 FTOH=10:2 Fluorotelomer alcohol C.sub.12H.sub.5F.sub.21O C12 865-86-1 564.13 Di-substituted polyfluorinated phosphate ester 6:2 diPAP= 6:2 fluorotelomer phosphate diester C.sub.16H.sub.9F.sub.26PO.sub.4 C16 57677-95-9 790.17 8:2 diPAP = 8:2 fluorotelomer phosphate diester C.sub.20H.sub.9F.sub.34PO.sub.4 C20 678-41-1 990.2 Perluoroalkane sulfonamido ethanols FBSE= perdluorobutane sulfonamidoethanol C.sub.6H.sub.6F.sub.9NO.sub.3S C6 34454-99-4 343.17 N-MeFBSE=N-Methyl-Perfluorobutane sulfonamido ethanol C.sub.7H.sub.8F.sub.9NO.sub.3S C7 34454-97-2 357.19 N-EtFBSE= N-ethyl-Perfluorobutane sulfonamido ethanol C.sub.8H.sub.10F.sub.9NO.sub.3S C8 34449-89-3 371.22 FOSE= perfluorooctane sulfonamidoethanol C.sub.10H.sub.6F.sub.17NO.sub.3S C10 10116-92-4 543.19 MeFOSE=N-methyl perfluorooctane sulfoamido ethanol C.sub.11H.sub.8F.sub.17NO.sub.3S C11 24448-09-7 557.22 EtFOSE=N-ethyl perfluorooctane sulfoamido ethanol C.sub.12H.sub.10F.sub.17NO.sub.3 S C12 1691-99-2 571.25 FASA FBSA= perfluorobutane sulfonamide C.sub.4H.sub.2F.sub.9NO.sub.2S C4 30334-69-1 299.12 N-MeFBSA= N-Methyl perfluorobutane sulfonamide C.sub.5H.sub.4F.sub.9NO.sub.2S C5 68298-12-4 313.14 N-EtFBSA=N-ethyl-perfluorobutane sulfonamide C.sub.6H.sub.6F.sub.9NO.sub.2S C6 40630-67-9 327.17 PFOSA = perfluorooctane sulfonamide C.sub.8H.sub.2F.sub.17NO.sub.2S C8 754-91-6 499.14 N-MeFOSA=N-methyl perfluorooctane sulfonamide C.sub.9H.sub.4F.sub.17NO.sub.2S C9 31506-32-8 513.17 N-EtFOSA = N-ethyl perfluorooctane sulfonamide C.sub.10H.sub.6F.sub.17NO.sub.2S C10 4151-50-2 527.19 Other (PFESAs) F-53B=Chlorinated polyfluoroalkyl ether sulfonate C.sub.8ClF.sub.16KO.sub.4S C8 73606-19-6 570.67 Other PFECA PFMOAA= Perfluoro-2-methoxyacetic acid C.sub.3HF.sub.5O.sub.3 C3 674-13-5 180.03 PFO2HxA=3,5-dioxahexanoic acid C.sub.4HF.sub.7O.sub.4 C4 39492-88-1 246.04 PFO3OA= 3,5,7-trioxaoctanoic acid C.sub.5HF.sub.9O.sub.5 C5 39492-89-2 312.04 Gen-X=hexafluoropropylene oxide dimer acid C.sub.6HF.sub.11O.sub.3 C6 13252-13-6 330.05 ADONA=dodecafluoro-3H-4,8-dioxanonanoate C.sub.7H.sub.5F.sub.12NO.sub.4 C7 958445-44-8 395.101 HFPO-TA=hexafluoropropylene oxide trimer acid C.sub.9HF.sub.17O.sub.4 C9 13252-14-7 496.07 FTS : Fluorinated telomer sulfonate n:2 FTOH : Fluorotelomer alcohol FASA : Perfluoroalkane sulfonamide PFECA : perfluoro-ether carboxylic acids

[0270] STEP 4, the concentration data of each targeted compound is compared to a threshold, T_Targ. If the concentration data exceed the threshold, the process goes to STEP 5, if no, the process goes to STEP 7 and stops. In STEP 4, alternatively, the concentration data of all detected short chain targeted PFAS may be added, the concentration data of all detected long chain targeted PFAS may be added, and each sum may be compared to a threshold dedicated to short, respectively long, chain PFAS. The threshold(s) is (are) typically imposed by legislation or the user.

[0271] STEP 5 generates an activating signal for activating the PFAS unit. Here, as STEP 4 provides information either for particular short or long chain PFAS that exceed minimal content or for two high concentrations of short or long chain PFAS, a signal for activating one of the short chain PFAS dedicated treatment stage, Signal_Short, and/or a signal for activating one of the long chain PFAS dedicated treatment stage, Signal_Long can be generated.

[0272] In this STEP 5, the activating signal is configured to activate at least one PFAS dedicated treatment stage which is selected by means of a model using a data basis built from compilation of results of lab-scale and/or pilot-scale tests for each PFAS treatment stage performed on several effluents having different total organic carbon contents and/or minerals contents and/or pH values. By way of example, this data base can comprise information data characteristics of the effluents tested, PFAS analysis of the effluents tested, treatment performances in terms of PFAS removal of each PFAS treatment stage and the associated costs.

[0273] The treatment stage to activate is in particular selected depending on the type of PFAS, on the inlet concentration of the FPAS determined in STEP 3, on the removal efficiency to attain and/or on the treatment cost, as previously explained. When several treatments may be selected for removal of different PFAS, then the model may select at least one treatment stage allowing the removal of the most critical PFAS, in particular to attain an outlet concentration on said most critical PFAS compliant with legislation. Further treatment stage(s) may be selected for the removal of other PFAS.

[0274] STEP 6, Signal_Short and/or Signal_Long is transmitted to the PFAS unit, more specifically to the appropriate treatment stage, resulting in its activation.

[0275] Above STEPS 2, 4, 5, 6, 7 may be performed by the above described control unit 60, in particular by the treatment means 62. STEPS 1 and 3 may be performed by the above described analysis unit 70.

[0276] STEP 1 is regularly reiterated whatever the issue of STEP 1. At the beginning of the process, none of the treatment stages are activated. When one or several treatment stages have been activated following the receipt of an activation signal (STEP 6), they remain activated until the receipt of a deactivation signal. Such deactivation signal may be generated in STEP 7 if, in a previous iteration, an activation signal has been transmitted in STEP 6. STEP 7 then also transmits the deactivation signal to the PFAS unit, resulting in its deactivation.

[0277] In a second embodiment, in STEP 1, the information data may be obtained by another non targeted analysis giving global fluorine information such as combustion ion chromatography, particle-induced gamma ray emission spectroscopy, and/or fluorine nucleic magnetic resonance. In this case, information data representative of the presence of carbon-fluorine bonds or of the presence of fluorine are obtained. These information data are typically a PFAS specific signal intensity, a PFAS specific signal surface, a sum of the intensities of a group of PFAS specific signals, a sum of the surfaces of a group of PFAS specific signals, a sum of the intensities of all PFAS specific signals.

[0278] These information data are considered as data representative of the presence of PFAS when they are above a predetermined threshold. This threshold depends on the sensibility of the analysis and can be determined from previously performed analysis on effluents having different known concentrations of PFAS.

[0279] The information data are then representative of the presence/absence of PFAS when the information data registered during the analysis is above/below this predetermined threshold. If absence is detected, the process goes to STEP 7. If presence of PFAS is detected, the process goes directly to STEP 3, where a targeted analysis is performed on each of the PFAS of a registered list (for example the list of table 1). STEPS 4 to 7 are then performed as described above and STEP 1 is regularly reiterated.

[0280] In a third embodiment, STEP 2 may also be omitted. STEP 1 then provides data representative of the presence or absence of PFAS from a non targeted analysis. These data are for example the global intensity of a graph obtained by a non-targeted analysis typically high resolution mass spectroscopy. More specifically, this global intensity is a global intensity of signals specific to PFAS, obtained for example by extracting the data as a function of mass fragments to retain only those coming from PFAS compounds.

[0281] Then, always in STEP 1, data corresponding to an estimated total concentration of PFAS is estimated from the global intensity provided, using a previously built data base which correlates global intensities of PFAS with a total concentration of targeted PFAS.

[0282] STEP 1 then determines the absence of PFAS when this estimated total concentration of PFAS is below a predetermined threshold, typically imposed by legislation or a user, for example 100 ng/L. When presence of PFAS is detected, then the process goes to STEP 3 as disclosed above. If absence of PFAS is detected (estimated total concentration of PFAS above the predetermined threshold), the process goes to STEP 7.

[0283] The data base used in this STEP 1 may be built as described hereafter.

[0284] First, a non-targeted analysis (mass spectroscopy) is done on an effluent (corresponding to the liquid effluent to treat, more or less charged in dissolved organics and minerals) i.e. on several effluents having different total organic carbon contents and/or minerals contents and/or pH values. The global intensity of the graph obtained by this non-targeted analysis is then registered for each effluent analyzed.

[0285] Then, a targeted analysis is performed on the same effluents for a registered list of PFAS targeted compounds (for example the 60 compounds of table 1 above) allowing the determination of the concentration of each of these targeted compounds.

[0286] The non-targeted analysis and targeted analysis results are then statistically analyzed so as to correlate a global intensity of the graph obtained by the non-targeted analysis with the total concentration of the targeted compounds.

[0287] The data base also includes the predetermined threshold level for PFAS presence, corresponding for example to a total concentration of PFAS of at least 100 ng/L.

[0288] This data base may also include a classification of the PFAS compounds and a specific PFAS treatment stage associated to each class of PFAS compounds. This classification of the PFAS can include the three main following classes: [0289] class 1: short chain PFAS [0290] class 2: long chain polar PFAS, [0291] class 3: long chain apolar PFAS.

[0292] in STEP 5, the activating signal generated is for activating a least one treatment stage selected by a model using the above data base further including information characteristics of the effluents tested, PFAS analysis of the effluents tested, treatment performances in terms of PFAS removal of each PFAS treatment stage and the associated costs.

[0293] This selection can be performed as explained with respect to the first embodiment depending on the type of PFAS, on the initial concentration of the FPAS determined in STEP 3, on the removal efficiency to attain and/or on the treatment cost.

[0294] When no critical PFAS is to be remove, the selection may include the determination of the analytic class to which belongs the PFAS for which a targeted analysis has been performed and the selection of at least one treatment allowing to attain a specific removal efficiency for this class of PFAS and for the inlet concentrations of this class of PFAS determined in STEP 3.

[0295] When one or more critical PFAS are to be removed, the selection may include: [0296] selection of the treatment stage having the higher removal efficiency towards the most critical PFAS for the inlet concentration of said critical PFAS determined in STEP 3, [0297] if necessary to achieve a specific removal efficiency of other critical PFAS, selection of at least one other treatment stage for the inlet concentration of said other critical PFAS determined in STEP 3.

[0298] Thus, this may result in the combination of two reagents in a same vessel, or to the combination of two or more treatments in series (a first vessel with a first reagent followed by a second vessel with a second reagent, or a first vessel with a first reagent followed by a membrane filtration, ...) and/or in parallel.

[0299] In a fourth embodiment, STEPS 1 and 2 may be omitted. In such a case, If the concentration data exceed the threshold previously mentioned for STEP 4, data representative of the presence of PFAS are generated and the process goes to STEP 5, if not, data representative of the absence of PFAS are generated, the process goes to STEP 7 and stops. STEPs 5 and 6 may be performed as previously described.

[0300] In the third and fourth embodiments, STEPS 4 to 7 are performed as described with respect to the first embodiment and STEP 1 is regularly reiterated.

EXAMPLES

[0301] A P-CDP polymer has been tested for PFAS removal in a settling tank. The P-CDP polymer is obtained by using a fluorine aryl cross-linker to cross-link β-CD. It has been used in powder form or granular form at a dose of 10 to 20 mg/L.

[0302] The properties of P-CDP polymer are gathered in table 2:

TABLE-US-00002 Surface Area Standard NF EN ISO 18757-june 2006 Up to 450 m.sup.2/g Averaged Apparent Density ASTM D2854-09 (2019). Standard Test Method for Apparent Density of Activated Carbon. 0.56 g/cc Effective size (powder) Standard NF EN ISO 8130-1 (2019-05-08) Averaged 78 .Math.m Effective size (granules) Standards NF EN 12915-1-july 2009 and NF EN 12902-february 2005 212-500 .Math.m; 500-1500 .Math.m

[0303] Batch experiments were performed on tumblers with a series of representative adsorbent doses. Water samples were collected and analyzed at time points of 5 minutes, 10 minutes and 70 minutes. All batch reactors were tumbled for 15 minutes and then stopped for the remaining 55 minutes to let the adsorbents settle until the 70-min samples were collected. This is to simulate the mixing pattern at Rahway Facility. The water samples were analyzed standard methods on HPLC-MS/MS (Thermofisher, QExactive). For each adsorbent dose and time point, triplicate was performed to quantify error and guarantee the reliability of each data point. The removal of each PFAS at 70 minutes is presented in Table 3. These results show efficiency of the P-CDP polymer to remove short chain PFAS.

TABLE-US-00003 PFAS C# CAS # Background concentration m% removal mass ppt 5 mg/L 10 mg/L 20 mg/L 30 mg/L 50 mg/L PFPeA C5 2706-90-3 5.6 1.6 6.9 12.5 18.2 30.6 PFBS C4 375-73-5 4.0 49.7 71.1 100.0 100.0 100.0 PFHxA C6 307-24-4 7.0 10.7 24.4 37.4 52.5 69.5 PFHpA C7 375-85-9 6.2 24.6 41.6 61.9 75.1 86.2 PFHxS C6 355-46-4 432-50-8 6.3 67.7 83.2 89.5 94.1 100.0 PFOA C8 335-67-1 32.9 30.0 53.7 76.5 87.6 94.9 PFOS C8 1763-23-1 7.9 76.5 100.0 100.0 100.0 100.0 PFNA C9 375-95-1 1.8 33.0 100.0 100.0 100.0 100.0

[0304] Similar results have been observed at 10 and 70 minutes demonstrating the rapid removal kinetic of the absorbent, as can also be seen on FIGS. 3 and 4 which show the mass percent uptake of the adsorbent for each PFAS at 5, 10 and 70 min (from left to right for each PFAS), for two doses 20 mg/L (FIG. 3) and 50 mg/L (FIG. 4). Bars on the figures represent the measurement error and minimum and maximum uptake.