CN117023750B - Treatment method of fluorine-containing wastewater - Google Patents
Treatment method of fluorine-containing wastewater Download PDFInfo
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- CN117023750B CN117023750B CN202311297165.5A CN202311297165A CN117023750B CN 117023750 B CN117023750 B CN 117023750B CN 202311297165 A CN202311297165 A CN 202311297165A CN 117023750 B CN117023750 B CN 117023750B
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- 239000011737 fluorine Substances 0.000 title claims abstract description 90
- 229910052731 fluorine Inorganic materials 0.000 title claims abstract description 90
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 title claims abstract description 87
- 239000002351 wastewater Substances 0.000 title claims abstract description 69
- 238000000034 method Methods 0.000 title claims abstract description 48
- 239000002131 composite material Substances 0.000 claims abstract description 119
- 229920001577 copolymer Polymers 0.000 claims abstract description 90
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 85
- 238000006243 chemical reaction Methods 0.000 claims abstract description 66
- 238000004062 sedimentation Methods 0.000 claims abstract description 62
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical group NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 claims abstract description 60
- 238000006115 defluorination reaction Methods 0.000 claims abstract description 37
- WHNWPMSKXPGLAX-UHFFFAOYSA-N N-Vinyl-2-pyrrolidone Chemical group C=CN1CCCC1=O WHNWPMSKXPGLAX-UHFFFAOYSA-N 0.000 claims abstract description 31
- 230000001105 regulatory effect Effects 0.000 claims abstract description 25
- 238000000926 separation method Methods 0.000 claims abstract description 13
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims abstract description 10
- 239000000920 calcium hydroxide Substances 0.000 claims abstract description 10
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims abstract description 10
- 239000000178 monomer Substances 0.000 claims description 43
- -1 pyridyl quaternary ammonium salt Chemical class 0.000 claims description 43
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 39
- 238000003756 stirring Methods 0.000 claims description 30
- 239000003999 initiator Substances 0.000 claims description 27
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 21
- 238000001035 drying Methods 0.000 claims description 13
- 238000005406 washing Methods 0.000 claims description 13
- MPFLRYZEEAQMLQ-UHFFFAOYSA-N dinicotinic acid Chemical compound OC(=O)C1=CN=CC(C(O)=O)=C1 MPFLRYZEEAQMLQ-UHFFFAOYSA-N 0.000 claims description 7
- SZTBMYHIYNGYIA-UHFFFAOYSA-N 2-chloroacrylic acid Chemical compound OC(=O)C(Cl)=C SZTBMYHIYNGYIA-UHFFFAOYSA-N 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 238000010517 secondary reaction Methods 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 5
- IDGUHHHQCWSQLU-UHFFFAOYSA-N ethanol;hydrate Chemical compound O.CCO IDGUHHHQCWSQLU-UHFFFAOYSA-N 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 3
- 238000002390 rotary evaporation Methods 0.000 claims description 3
- 238000000967 suction filtration Methods 0.000 claims description 3
- 150000003863 ammonium salts Chemical class 0.000 claims 1
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 238000004065 wastewater treatment Methods 0.000 abstract description 3
- 238000003672 processing method Methods 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 28
- 239000008367 deionised water Substances 0.000 description 26
- 229910021641 deionized water Inorganic materials 0.000 description 26
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 23
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 20
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium persulfate Chemical group [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 description 20
- 239000008394 flocculating agent Substances 0.000 description 20
- 239000011259 mixed solution Substances 0.000 description 20
- 230000008569 process Effects 0.000 description 18
- GQOKIYDTHHZSCJ-UHFFFAOYSA-M dimethyl-bis(prop-2-enyl)azanium;chloride Chemical group [Cl-].C=CC[N+](C)(C)CC=C GQOKIYDTHHZSCJ-UHFFFAOYSA-M 0.000 description 17
- 238000010521 absorption reaction Methods 0.000 description 16
- 238000006116 polymerization reaction Methods 0.000 description 16
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 239000003995 emulsifying agent Substances 0.000 description 12
- 239000000047 product Substances 0.000 description 11
- 238000007792 addition Methods 0.000 description 10
- 229910001870 ammonium persulfate Inorganic materials 0.000 description 10
- 238000001914 filtration Methods 0.000 description 10
- 238000010438 heat treatment Methods 0.000 description 10
- 229910052757 nitrogen Inorganic materials 0.000 description 10
- 238000011056 performance test Methods 0.000 description 10
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 10
- 150000002500 ions Chemical class 0.000 description 9
- 239000000243 solution Substances 0.000 description 8
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical group C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 7
- 238000001556 precipitation Methods 0.000 description 7
- 239000011734 sodium Substances 0.000 description 7
- 229910052708 sodium Inorganic materials 0.000 description 7
- 239000007788 liquid Substances 0.000 description 6
- 229920002401 polyacrylamide Polymers 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- 238000001179 sorption measurement Methods 0.000 description 6
- 239000000084 colloidal system Substances 0.000 description 5
- 238000002329 infrared spectrum Methods 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 239000011775 sodium fluoride Substances 0.000 description 5
- 235000013024 sodium fluoride Nutrition 0.000 description 5
- 229910021642 ultra pure water Inorganic materials 0.000 description 5
- 239000012498 ultrapure water Substances 0.000 description 5
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 4
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical group C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 4
- 235000011941 Tilia x europaea Nutrition 0.000 description 4
- 229910001424 calcium ion Inorganic materials 0.000 description 4
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 4
- 238000005189 flocculation Methods 0.000 description 4
- 230000016615 flocculation Effects 0.000 description 4
- 239000004571 lime Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000008267 milk Substances 0.000 description 4
- 210000004080 milk Anatomy 0.000 description 4
- 235000013336 milk Nutrition 0.000 description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 3
- WPUINVXKIPAAHK-UHFFFAOYSA-N aluminum;potassium;oxygen(2-) Chemical compound [O-2].[O-2].[Al+3].[K+] WPUINVXKIPAAHK-UHFFFAOYSA-N 0.000 description 3
- 150000001450 anions Chemical class 0.000 description 3
- 150000001768 cations Chemical class 0.000 description 3
- 238000005345 coagulation Methods 0.000 description 3
- 230000015271 coagulation Effects 0.000 description 3
- 238000010790 dilution Methods 0.000 description 3
- 239000012895 dilution Substances 0.000 description 3
- 235000019441 ethanol Nutrition 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 229910052749 magnesium Inorganic materials 0.000 description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 3
- 238000004064 recycling Methods 0.000 description 3
- 239000006228 supernatant Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 238000000862 absorption spectrum Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 159000000007 calcium salts Chemical class 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000009388 chemical precipitation Methods 0.000 description 2
- 230000002860 competitive effect Effects 0.000 description 2
- 230000003750 conditioning effect Effects 0.000 description 2
- 239000010842 industrial wastewater Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- CYUOWZRAOZFACA-UHFFFAOYSA-N aluminum iron Chemical compound [Al].[Fe] CYUOWZRAOZFACA-UHFFFAOYSA-N 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 230000001112 coagulating effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000010408 sweeping Methods 0.000 description 1
Landscapes
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention discloses a method for treating fluorine-containing wastewater, and belongs to the technical field of fluorine-containing wastewater treatment. The processing method comprises the following steps: the fluorine-containing wastewater enters an adjusting tank, and effluent of the adjusting tank is obtained after homogenizing the uniform quantity; the effluent of the regulating tank enters a first-stage reaction tank, calcium hydroxide and a composite flocculant are added for reaction, and the effluent of the first-stage reaction tank enters a first-stage sedimentation tank for mud-water separation to obtain effluent of the first-stage sedimentation tank; adding a composite flocculant to react after the effluent of the first-stage sedimentation tank enters a second-stage reaction tank, and performing mud-water separation on the effluent of the second-stage reaction tank to obtain the effluent of the second-stage sedimentation tank; the composite flocculant comprises an inorganic flocculant and an organic flocculant, wherein the organic flocculant is a copolymer, and the copolymer is composed of an acrylamide unit and an alkenyl quaternary ammonium salt unit, or the copolymer is composed of an acrylamide unit, an alkenyl quaternary ammonium salt unit and an N-vinyl pyrrolidone unit. The treatment method has high defluorination efficiency and operation stability.
Description
Technical Field
The invention belongs to the technical field of fluorine-containing wastewater treatment, and particularly relates to a treatment method of fluorine-containing wastewater.
Background
With the acceleration of the domestic substitution process of electronic products in recent years, the electronic industry becomes one of the main sources of fluorine-containing wastewater, the treatment of industrial fluorine-containing wastewater becomes more and more important based on the environmental protection and the consideration of production processes, and the main current treatment processes comprise a chemical precipitation method and a coagulating sedimentation method. The chemical precipitation method is mainly applied to raw water high fluorine-containing wastewater (more than or equal to 100 mg/L), the most common process is a calcium salt precipitation method, namely, calcium hydroxide (lime milk) is added into fluorine-containing water to regulate the pH value and simultaneously carry out preliminary fluorine reduction, and because the calcium hydroxide is slightly dissolved in water, after the process is treated, the fluorine content (30-50 mg/L) of treated water is obtained, at the moment, the process can be regulated to regulate the pH value by adding the calcium hydroxide (lime milk) while adding a proper amount of other soluble calcium salts (such as CaCl) 2 ) Increasing the concentration of calcium ions, thereby accelerating the reaction to lead fluoride ions and Ca in the wastewater 2+ Reaction to CaF 2 Precipitation is carried out, and the fluorine content (10-15 mg/L) of the water is treated. The coagulation sedimentation method mainly adopts an aluminum salt flocculant to remove fluorine in industrial wastewater, and the mechanism is that a coagulant is utilized to form colloid particles with positive charges, the colloid particles absorb fluoride ions in water, the charges of the colloid particles in water are neutralized, an electric double layer is compressed, so that the colloid particles in water are rapidly destabilized, fluoride ions and colloid are co-precipitated under the actions of an adsorption bridge, net capturing or rolling sweeping, and finally the fluoride ions in water are separated through solid-liquid separation. In the prior art, the invention patent with the application number of 2022117021315 discloses a fluoride removal process for fluoride-containing industrial wastewater, which comprises the following steps of S1 precipitation: introducing fluorine-containing wastewater into a sedimentation tank for sedimentation, and then taking supernatant to obtain a sediment-removing solution; s2, primary defluorination: adjusting the pH of the precipitation removing liquid to 6.5-7.5, adding 3500-4000mg/l lime milk, settling after the reaction is complete, and taking supernatant to obtain a first-stage fluorine removing liquid; s3, secondary defluorination: adjusting the pH of the primary defluorination liquid to 6.5-7.5, adding 3500-4000mg/l lime milk, settling after the reaction is complete, and taking supernatant to obtain a secondary defluorination liquid;s4, removing hardness: after the secondary defluorination liquid is subjected to hardness removal, treated wastewater is obtained; the defluorination process can greatly reduce the content of fluoride ions in the wastewater and control the hardness of the treated wastewater, so that the treated wastewater meets the evaporation requirement. In the prior art, the invention patent with the application number of 2022117021315 discloses a semiconductor fluorine-containing wastewater treatment system and a process, and the structure of the system comprises a fluorine-containing wastewater collecting tank, a fluorine-containing wastewater regulating tank, a first-stage reaction tank, a first-stage coagulation tank, a first-stage flocculation tank, a first-stage sedimentation tank, a second-stage reaction tank, a second-stage flocculation tank, a second-stage sedimentation tank and a discharge tank which are sequentially connected through pipelines; and water pumps are respectively arranged on the pipeline between the fluorine-containing wastewater water collecting tank and the fluorine-containing wastewater regulating tank and the pipeline between the fluorine-containing wastewater regulating tank and the primary reaction tank. The first-stage reaction tank is connected with a first NaOH dosing tank and a first H 2 SO 4 Dosing bin and first CaCl 2 The first-stage coagulation tank is connected with a second CaCl 2 The first flocculation tank is connected with the first PAM dosing tank, and the second reaction tank is connected with the second NaOH dosing tank and the second H 2 SO 4 The second flocculation tank is connected with the second PAM dosing tank.
Disclosure of Invention
The invention aims to provide a composite flocculant with a good fluoride ion removal effect.
The technical scheme adopted by the invention for achieving the purpose is as follows:
a composite flocculant, comprising,
-an inorganic flocculant selected from polyaluminum chloride and/or polyaluminum iron; and, a step of, in the first embodiment,
-an organic flocculant, the organic flocculant being a copolymer consisting of acrylamide units and alkenyl quaternary ammonium salt units, or the copolymer consisting of acrylamide units, alkenyl quaternary ammonium salt units and N-vinylpyrrolidone units. The composite flocculant has good defluorination performance and precipitation performance, and can rapidly and effectively remove fluoride ions in the fluorine-containing wastewater under the condition of small dosage, thereby realizing the advanced treatment of the fluorine-containing wastewater; this is probably due to the fact that the composite flocculant of the invention has more active groups, which can promote the colloidal particles to form flocculates more rapidly, thereby accelerating the precipitation speed and strengthening the defluorination effect.
In one embodiment, the alkenyl quaternary ammonium salt units are dimethyldiallylammonium chloride units and the copolymer is comprised of acrylamide units, dimethyldiallylammonium chloride units, and N-vinylpyrrolidone units.
In one embodiment, the method of making the copolymer is: monomers of acrylamide, dimethyl diallyl ammonium chloride and N-vinyl pyrrolidone are polymerized under the action of an initiator to obtain a copolymer. The copolymer is composed of an acrylamide unit, a dimethyl diallyl ammonium chloride unit and an N-vinyl pyrrolidone unit, and has better selectivity and higher adsorption performance on fluoride ions when the copolymer is used together with an inorganic flocculant.
In a preferred embodiment, the molar ratio of acrylamide, dimethyldiallylammonium chloride and N-vinylpyrrolidone is from 1:0.2 to 0.6:0.1 to 0.3.
In a preferred embodiment, the initiator is ammonium persulfate and the initiator is used in an amount of from 0.1 to 2% by weight of the total monomer.
In a preferred embodiment, the polymerization temperature is 50 to 70℃and the polymerization time is 6 to 24 hours.
In a preferred embodiment, the copolymer is prepared by:
1) Adding acrylamide, dimethyl diallyl ammonium chloride and N-vinyl pyrrolidone into deionized water, and uniformly stirring to obtain a monomer mixed solution, wherein the weight ratio of the acrylamide to the deionized water is 5-10:100;
2) Introducing nitrogen into the monomer mixed solution for 10-40min, adding an initiator, heating to 50-70 ℃ for polymerization reaction for 6-24h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3-5 times, and drying to obtain the copolymer.
In a preferred embodiment, the alkenyl quaternary ammonium salt units are pyridyl quaternary ammonium salt units, the pyridyl quaternary ammonium salt being obtained by reacting 3, 5-pyridinedicarboxylic acid with 2-chloroacrylic acid; the copolymer is composed of an acrylamide unit, a pyridyl quaternary ammonium salt unit and an N-vinyl pyrrolidone unit. Because the composite flocculant has a copolymer composed of an acrylamide unit, a pyridyl quaternary ammonium salt unit and an N-vinyl pyrrolidone unit, the composite flocculant has better selectivity and higher adsorption performance on fluoride ions. In addition, other anions and cations are commonly coexistent in the fluorine-containing wastewater, and competitive adsorption or reaction of coexistent ions can influence the fluorine removal effect of the composite flocculant, while the coexistent ions have little influence on the fluorine removal effect of the composite flocculant.
In a more preferred embodiment, the pyridyl quaternary ammonium salt has the formula。
In a more preferred embodiment, the method of preparing the pyridylammonium salt is:
adding 3, 5-pyridine dicarboxylic acid and 2-chloroacrylic acid into 50-60v/v% ethanol water solution, stirring uniformly, stirring at 80-110 ℃ for reaction for 24-48h, performing rotary evaporation after the reaction is finished, washing with ethanol for 2-4 times, performing suction filtration, and drying to obtain the pyridyl quaternary ammonium salt. More preferably, the molar ratio of 3, 5-pyridinedicarboxylic acid to 2-chloroacrylic acid is 1:1. More preferably, the ratio of 3, 5-dipicolinic acid to aqueous ethanol is 1g:10-20mL.
In one embodiment, the method of making the copolymer is: the monomer acrylamide, the pyridyl quaternary ammonium salt and the N-vinyl pyrrolidone are polymerized under the action of an initiator to obtain the copolymer.
In a preferred embodiment, the molar ratio of acrylamide, pyridylammonium salt and N-vinylpyrrolidone is from 1:0.1 to 0.3:0.1 to 0.3.
In a preferred embodiment, the initiator is ammonium persulfate and the initiator is used in an amount of from 0.1 to 2% by weight of the total monomer.
In a preferred embodiment, the polymerization temperature is 50 to 70℃and the polymerization time is 6 to 24 hours.
In a preferred embodiment, the copolymer is prepared by:
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt, N-vinyl pyrrolidone and an emulsifier OP-10 into deionized water, wherein the weight ratio of the acrylamide to the deionized water is 5-10:100, and the weight ratio of the emulsifier OP-10 to the deionized water is 0.5-5:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 10-40min, adding an initiator, heating to 50-70 ℃ for polymerization reaction for 6-24h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3-5 times, and drying to obtain the copolymer.
In one embodiment, the alkenyl quaternary ammonium salt unit is a pyridyl quaternary ammonium salt unit, the pyridyl quaternary ammonium salt being obtained by reacting 3, 5-pyridinedicarboxylic acid with 2-chloroacrylic acid; the copolymer is composed of acrylamide units and pyridyl quaternary ammonium salt units. Because the composite flocculant has the copolymer formed by the acrylamide unit and the pyridyl quaternary ammonium salt unit, the composite flocculant has better selectivity and higher adsorption performance on fluoride ions. In addition, other anions and cations are commonly coexistent in the fluorine-containing wastewater, and competitive adsorption or reaction of coexistent ions can influence the fluorine removal effect of the composite flocculant, while the coexistent ions have little influence on the fluorine removal effect of the composite flocculant.
In one embodiment, the method of making the copolymer is: polymerizing monomer acrylamide and pyridyl quaternary ammonium salt under the action of initiator to obtain copolymer.
In a preferred embodiment, the molar ratio of acrylamide to pyridylammonium salt is from 1:0.1 to 0.3.
In a preferred embodiment, the initiator is ammonium persulfate and the initiator is used in an amount of from 0.1 to 2% by weight of the total monomer.
In a preferred embodiment, the polymerization temperature is 50 to 70℃and the polymerization time is 6 to 24 hours.
In a preferred embodiment, the copolymer is prepared by:
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt and emulsifier OP-10 into deionized water, wherein the weight ratio of the acrylamide to the deionized water is 5-10:100, and the weight ratio of the emulsifier OP-10 to the deionized water is 0.5-5:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 10-40min, adding an initiator, heating to 50-70 ℃ for polymerization reaction for 6-24h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3-5 times, and drying to obtain the copolymer.
In one embodiment, the mass ratio of inorganic flocculant to organic flocculant is 100:0.1-10.
In one embodiment, the polyaluminum iron is selected from polyaluminum ferric chloride, polyaluminum ferric silicate, polyaluminum ferric sulfate, or polyaluminum ferric diacid.
In one embodiment, the inorganic flocculant is polyaluminum chloride and polyaluminum ferric silicate, and the mass ratio of the polyaluminum chloride to the polyaluminum ferric silicate is 1:0.1-0.3. When the polyaluminum chloride and polysilicate aluminum iron complex copolymer is used, the composite flocculant has the best effect of treating fluorine-containing wastewater.
The invention also discloses application of the composite flocculant in treating fluorine-containing wastewater.
In one embodiment, the use includes the addition of a composite flocculant to the reaction tank.
Another object of the present invention is to provide a method for treating fluorine-containing wastewater with high fluorine removal efficiency and high operation stability.
The technical scheme adopted by the invention for achieving the purpose is as follows:
a method for treating fluorine-containing wastewater comprises the following steps,
step 1: the fluorine-containing wastewater enters an adjusting tank, and effluent of the adjusting tank is obtained after homogenizing the uniform quantity;
step 2: feeding the effluent of the regulating tank into a first-stage reaction tank, adding calcium hydroxide and the composite flocculant for reaction, and feeding the effluent of the first-stage reaction tank into a first-stage sedimentation tank for mud-water separation to obtain effluent of the first-stage sedimentation tank;
step 3: and after the effluent of the first-stage sedimentation tank enters the second-stage reaction tank, adding the composite flocculant for reaction, and performing mud-water separation on the effluent of the second-stage reaction tank to obtain the effluent of the second-stage sedimentation tank. In the treatment method, the fluorine ion content of the effluent of the regulating tank is more than or equal to 100mg/L, the fluorine ion content of the effluent of the primary sedimentation tank is less than or equal to 30mg/L, and the fluorine ion content of the effluent of the secondary sedimentation tank is less than or equal to 10mg/L, so that the treatment method has high fluorine removal efficiency, is not influenced by the change of the water quality of the wastewater, has high operation stability, and is safe and convenient to operate. When the fluorine ion content in the effluent of the secondary sedimentation tank is less than 1mg/L, the effluent of the secondary sedimentation tank is treated water, the treated water directly enters a recycling device or flows back to an adjusting tank for dilution, and the treated water is recycled to the adjusting tank, so that the pH adjusting treatment cost can be saved, the treated water can be diluted with raw water, the fluorine content of the incoming water can be greatly reduced, the subsequent treatment pressure can be reduced, and the comprehensive treatment cost can be reduced; and when the fluorine ion content in the effluent of the secondary sedimentation tank is 1-10mg/L, the effluent of the secondary sedimentation tank enters a tertiary reaction tank for treatment.
In one embodiment, the pH in the conditioning tank is controlled to be between 6.0 and 7.0.
In one embodiment, the pH is adjusted in the conditioning tank using a 1mol/L NaOH solution and/or a 1mol/L HCl solution.
In one embodiment, calcium hydroxide is added into the primary reaction tank firstly, then stirring is carried out for 10-60min, then a composite flocculant is added, pH is regulated to 6.0-7.0 by using meta-aluminate, and stirring is carried out for 10-60min continuously.
In a preferred embodiment, the amount of calcium hydroxide added to the primary reaction tank is 0.1-10g/L wastewater.
In a preferred embodiment, the amount of the composite flocculant added in the primary reaction tank is 10-100mg/L of wastewater.
In a preferred embodiment, the meta-aluminate is selected from sodium meta-aluminate, potassium meta-aluminate or magnesium meta-aluminate.
In one embodiment; adding a composite flocculant into the secondary reaction tank, regulating the pH value to 6.0-7.0 by using meta-aluminate, and stirring for reaction for 10-60min.
In a preferred embodiment, the amount of the composite flocculant added in the secondary reaction tank is 10-100mg/L of wastewater.
In a preferred embodiment, the meta-aluminate is selected from sodium meta-aluminate, potassium meta-aluminate or magnesium meta-aluminate.
In one embodiment, the method for treating fluorine-containing wastewater further comprises step 4: and after the effluent of the secondary sedimentation tank enters the tertiary reaction tank, adding the composite flocculant, and enabling the effluent of the tertiary reaction tank to enter the tertiary sedimentation tank for mud-water separation to obtain effluent of the tertiary sedimentation tank, namely treated water. The fluorine ion content in the treated water is less than 1mg/L, and the treated water directly enters the recycling equipment or flows back to the regulating tank for dilution, and the treated water is recycled to the regulating tank, so that the pH value regulating treatment cost can be saved, the treated water can be diluted with raw water, the fluorine content of the treated water can be greatly reduced, the subsequent treatment pressure can be reduced, and the comprehensive treatment cost can be reduced. In special cases, if the content of fluorine ions in the effluent of the three-stage sedimentation tank is 1-10mg/L, the effluent of the three-stage sedimentation tank is completely refluxed to the regulating tank for further treatment.
In one embodiment; adding a composite flocculant into the secondary reaction tank, regulating the pH value to 6.0-7.0 by using meta-aluminate, and stirring for reaction for 10-60min.
In a preferred embodiment, the amount of the composite flocculant added in the secondary reaction tank is 10-100mg/L of wastewater.
In a preferred embodiment, the meta-aluminate is selected from sodium meta-aluminate, potassium meta-aluminate or magnesium meta-aluminate.
In one embodiment, a method for treating fluorine-containing wastewater comprises the steps of,
step 1: the fluorine-containing wastewater enters an adjusting tank, air is adopted to mix and stir the inflow water, the pH value is controlled to be 6.0-7.0 after the uniform quantity is homogenized, and the outflow water of the adjusting tank is obtained;
step 2: adding the effluent of the regulating tank into a first-stage reaction tank, adding calcium hydroxide, stirring and reacting for 10-60min, adding a composite flocculant, regulating the pH to 6.0-7.0 by using meta-aluminate, continuously stirring and reacting for 10-60min, and adding the effluent of the first-stage reaction tank into a first-stage sedimentation tank for mud-water separation to obtain effluent of the first-stage sedimentation tank;
step 3: adding a composite flocculant into the effluent of the first-stage sedimentation tank, regulating the pH to 6.0-7.0 by using meta-aluminate, stirring and reacting for 10-60min, and separating mud from water in the second-stage sedimentation tank to obtain effluent of the second-stage sedimentation tank; if the content of the fluoride ions in the effluent of the secondary sedimentation tank is less than 1mg/L, the tertiary process can not run, and the effluent of the secondary sedimentation tank is treated water; if the content of the fluoride ions in the effluent of the secondary sedimentation tank is 1-10mg/L, the effluent of the secondary sedimentation tank enters a tertiary reaction tank;
step 4: and (3) after the effluent of the secondary sedimentation tank enters the tertiary reaction tank, adding a composite flocculant, regulating the pH to 6.0-7.0 by using sodium metaaluminate, stirring and reacting for 10-60min, and separating mud from water in the effluent of the tertiary reaction tank to obtain the effluent of the tertiary sedimentation tank, namely treated water.
The composite flocculant adopts a copolymer formed by an acrylamide unit, an alkenyl quaternary ammonium salt unit and an N-vinyl pyrrolidone unit, or a copolymer formed by an acrylamide unit, an alkenyl quaternary ammonium salt unit and an N-vinyl pyrrolidone unit. Therefore, the method has the following beneficial effects: the composite flocculant has good defluorination performance and precipitation performance, and can rapidly and effectively remove fluoride ions in the fluorine-containing wastewater under the condition of small dosage, thereby realizing the advanced treatment of the fluorine-containing wastewater; the presence of coexisting ions (for example, carbonate ions, sulfate ions, phosphate ions, calcium ions and other anions and cations) in the fluorine-containing wastewater has little influence on the fluorine removal effect of the composite flocculant. Therefore, the invention aims to provide a composite flocculant with better fluoride ion removal effect.
The invention adopts the composite flocculant to treat fluorine-containing wastewater, so the invention has the following beneficial effects: when the treatment method is used for treating the fluorine-containing wastewater with the fluorine ion content of more than or equal to 100mg/L, the fluorine ion content of the water discharged from the primary sedimentation tank is less than or equal to 30mg/L, the fluorine ion content of the water discharged from the secondary sedimentation tank is less than or equal to 10mg/L, the consumption of the composite flocculant is small, the fluorine removal efficiency is high, the influence of the water quality change of the wastewater is avoided, the operation stability is very high, and the operation is safe and convenient; the fluorine ion content in the treated water obtained by the treatment method is less than 1mg/L, and the treated water directly enters the recycling equipment or flows back to the regulating tank for dilution, and the treated water is recycled to the regulating tank, so that the pH regulating treatment cost can be saved, the treated water can be diluted with raw water, the fluorine content of the water can be greatly reduced, the subsequent treatment pressure can be reduced, and the comprehensive treatment cost can be reduced. Accordingly, an object of the present invention is to provide a method for treating fluorine-containing wastewater, which has high fluorine removal efficiency and high operation stability.
Drawings
FIG. 1 is an infrared spectrum of a copolymer;
FIG. 2 is a graph of the defluorination effect of a composite flocculant;
FIG. 3 is a graph showing the effect of coexisting ions on the defluorination properties of composite flocculants.
Detailed Description
The present invention will be further described in detail with reference to specific embodiments in order to make the objects, technical solutions and advantages of the present invention more apparent.
The experimental methods in the following examples are conventional methods unless otherwise specified. Materials, reagents and the like used in the examples described below are commercially available unless otherwise specified.
Example 1:
1. process for producing copolymer
1) Adding monomer acrylamide, dimethyl diallyl ammonium chloride and N-vinyl pyrrolidone into deionized water, wherein the molar ratio of the acrylamide to the dimethyl diallyl ammonium chloride to the N-vinyl pyrrolidone is 1:0.6:0.1, and the weight ratio of the acrylamide to the deionized water is 8:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 20min, adding an initiator ammonium persulfate, wherein the amount of the initiator is 0.5wt% of the total amount of the monomers, heating to 60 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-1-1.
2. A composite flocculant comprises polyaluminum chloride and a copolymer CP-1-1, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-1 is 100:10.
Example 2:
1. process for producing copolymer
1) Adding monomer acrylamide, dimethyl diallyl ammonium chloride and N-vinyl pyrrolidone into deionized water, wherein the molar ratio of the acrylamide to the dimethyl diallyl ammonium chloride to the N-vinyl pyrrolidone is 1:0.5:0.2, and the weight ratio of the acrylamide to the deionized water is 10:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 30min, adding an initiator ammonium persulfate, wherein the use amount of the initiator is 0.4wt% of the total amount of the monomers, heating to 58 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-1-2.
2. A composite flocculant comprises polyaluminum chloride and a copolymer CP-1-2, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-1-2 is 100:5.
Example 3:
a composite flocculant comprises polyaluminum ferric silicate and a copolymer CP-1-2 (prepared in example 2) in a mass ratio of 100:5.
Example 4:
a composite flocculant, which comprises an inorganic flocculant and a copolymer CP-1-2 (prepared in example 2), wherein the mass ratio of the inorganic flocculant to the copolymer CP-1-2 is 100:5; the inorganic flocculant is polyaluminum chloride and polyaluminum ferric silicate, and the mass ratio of the polyaluminum chloride to the polyaluminum ferric silicate is 1:0.2.
Example 5:
1. preparation method of pyridyl quaternary ammonium salt
Adding 3, 5-dipicolinic acid and 2-chloroacrylic acid with the molar ratio of 1:1 into 52v/v% ethanol water solution, uniformly stirring, stirring and reacting for 24 hours at 85 ℃ with the dosage ratio of 1g:18mL, performing rotary evaporation after the reaction is finished, washing for 3 times by ethanol, performing suction filtration, and drying to obtain the pyridyl quaternary ammonium salt. 1 H NMR （400MHz，CDCl 3 ） δ:9.46（s，2H），8.53（s，1H），6.24（s，1H），5.75（s，1H）。
2. Process for producing copolymer
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt, N-vinyl pyrrolidone and emulsifier OP-10 into deionized water, wherein the molar ratio of the acrylamide to the pyridyl quaternary ammonium salt to the N-vinyl pyrrolidone is 1:0.1:0.3, the weight ratio of the acrylamide to the deionized water is 8:100, and the weight ratio of the emulsifier OP-10 to the deionized water is 1:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 20min, adding an initiator ammonium persulfate, wherein the amount of the initiator is 0.5wt% of the total amount of the monomers, heating to 60 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-2-1.
3. A composite flocculant comprises polyaluminum chloride and a copolymer CP-2-1, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-2-1 is 100:10.
Example 6:
1. process for producing copolymer
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt (prepared in example 5), N-vinyl pyrrolidone and emulsifier OP-10 into deionized water, wherein the molar ratio of the acrylamide to the pyridyl quaternary ammonium salt to the N-vinyl pyrrolidone is 1:0.2:0.2, the weight ratio of the acrylamide to the deionized water is 10:100, the weight ratio of the emulsifier OP-10 to the deionized water is 2:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 30min, adding an initiator ammonium persulfate, wherein the use amount of the initiator is 0.4wt% of the total amount of the monomers, heating to 58 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-6.
2. A composite flocculant comprises polyaluminum chloride and a copolymer CP-2-2, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-2-2 is 100:5.
Example 7:
a composite flocculant comprises polyaluminum ferric silicate and a copolymer CP-2-2 (prepared in example 6) in a mass ratio of 100:5.
Example 8:
a composite flocculant, which comprises an inorganic flocculant and a copolymer CP-2-2 (prepared in example 6), wherein the mass ratio of the inorganic flocculant to the copolymer CP-2-2 is 100:5; the inorganic flocculant is polyaluminum chloride and polyaluminum ferric silicate, and the mass ratio of the polyaluminum chloride to the polyaluminum ferric silicate is 1:0.2.
Example 9:
1. process for producing copolymer
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt (prepared in example 5) and emulsifier OP-10 into deionized water, wherein the molar ratio of the acrylamide to the pyridyl quaternary ammonium salt is 1:0.1, the weight ratio of the acrylamide to the deionized water is 8:100, and the weight ratio of the emulsifier OP-10 to the deionized water is 1:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 20min, adding an initiator ammonium persulfate, wherein the amount of the initiator is 0.5wt% of the total amount of the monomers, heating to 60 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-3-1.
3. A composite flocculant comprises polyaluminum chloride and a copolymer CP-3-1, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-3-1 is 100:10.
Example 10:
1. process for producing copolymer
1) Adding monomer acrylamide, pyridyl quaternary ammonium salt (prepared in example 5) and emulsifier OP-10 into deionized water, wherein the molar ratio of the acrylamide to the pyridyl quaternary ammonium salt is 1:0.2, the weight ratio of the acrylamide to the deionized water is 10:100, and the weight ratio of the emulsifier OP-10 to the deionized water is 2:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 30min, adding an initiator ammonium persulfate, wherein the use amount of the initiator is 0.4wt% of the total amount of the monomers, heating to 58 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-3-2.
2. A composite flocculant comprises polyaluminum chloride and a copolymer CP-3-2, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-3-2 is 100:5.
Example 11:
a composite flocculant comprises aluminum ferric polysilicate and a copolymer CP-3-2 (prepared in example 10) in a mass ratio of 100:5.
Example 12:
a composite flocculant, which comprises an inorganic flocculant and a copolymer CP-3-2 (prepared in example 10), wherein the mass ratio of the inorganic flocculant to the copolymer is 100:5; the inorganic flocculant is polyaluminum chloride and polyaluminum ferric silicate, and the mass ratio of the polyaluminum chloride to the polyaluminum ferric silicate is 1:0.2.
Example 13:
1. process for producing copolymer
1) Adding monomer acrylamide and dimethyl diallyl ammonium chloride into deionized water, wherein the molar ratio of the acrylamide to the dimethyl diallyl ammonium chloride is 1:0.5, and the weight ratio of the acrylamide to the deionized water is 10:100, and uniformly stirring to obtain a monomer mixed solution;
2) Introducing nitrogen into the monomer mixed solution for 30min, adding an initiator ammonium persulfate, wherein the use amount of the initiator is 0.4wt% of the total amount of the monomers, heating to 58 ℃ for polymerization reaction for 12h, washing the product with absolute ethyl alcohol after the reaction is finished, suction-filtering for 3 times, and drying to obtain the copolymer CP-P1-2.
A composite flocculant comprises polyaluminum chloride and a copolymer CP-P1-2, wherein the mass ratio of the polyaluminum chloride to the copolymer CP-P1-2 is 100:5.
Example 14:
a composite flocculant comprises polyaluminium chloride and polyacrylamide, wherein the mass ratio of the polyaluminium chloride to the polyacrylamide is 100:5.
Example 15:
a method for treating fluorine-containing wastewater comprises the following steps,
step 1: the fluorine-containing wastewater enters an adjusting tank, air is adopted to mix and stir the inflow water, the pH value is controlled to be 6.5 after the uniform quantity is homogenized, and the outflow water of the adjusting tank is obtained;
step 2: adding the effluent of the regulating tank into a first-stage reaction tank, adding calcium hydroxide with the addition amount of 2g/L wastewater, stirring and reacting for 30min, adding a composite flocculant with the addition amount of 50mg/L wastewater, regulating the pH value to 6.5 by utilizing sodium metaaluminate, continuously stirring and reacting for 30min, and adding the effluent of the first-stage reaction tank into a first-stage sedimentation tank for mud-water separation to obtain effluent of the first-stage sedimentation tank;
step 3: adding a composite flocculant (the adding amount is 20mg/L of wastewater) after the effluent of the first-stage sedimentation tank enters a second-stage reaction tank, adjusting the pH value to 6.5 by using sodium metaaluminate, stirring and reacting for 30min, and performing mud-water separation on the effluent of the second-stage reaction tank into the second-stage sedimentation tank to obtain effluent of the second-stage sedimentation tank; if the content of the fluoride ions in the effluent of the secondary sedimentation tank is less than 1mg/L, the tertiary process can not run, and the effluent of the secondary sedimentation tank is treated water; if the content of the fluoride ions in the effluent of the secondary sedimentation tank is 1-10mg/L, the effluent of the secondary sedimentation tank enters a tertiary reaction tank;
step 4: and (3) after the effluent of the secondary sedimentation tank enters the tertiary reaction tank, adding a composite flocculant (the adding amount is 10mg/L of wastewater), adjusting the pH value to 6.5 by using sodium metaaluminate, stirring and reacting for 30min, and performing mud-water separation on the effluent of the tertiary reaction tank into the tertiary sedimentation tank to obtain the effluent of the tertiary sedimentation tank, namely treated water.
The composite flocculant is used in the treatment method of fluorine-containing wastewater, and the composite flocculant is used in examples 1-14.
Test example 1:
1. infrared absorption spectrum of copolymer
Testing infrared absorption spectrum of copolymer sample by Fourier transform infrared spectrometer with measurement range of 400-4000cm -1 。
FIG. 1 is an infrared spectrum of a copolymer, CP-1-2 represents the copolymer CP-1-2 produced in example 2, CP-2-2 represents the copolymer CP-2-2 produced in example 6, and CP-3-2 represents the copolymer CP-3-2 produced in example 10. In the infrared spectrum of copolymer CP-1-2, at 3430cm -1 Near occurrence of-NH 2 Characteristic absorption peak at 2970cm -1 And 2870cm -1 Characteristic absorption peak of methyl appears nearby at 1690cm -1 The characteristic absorption peak of c=o appears nearby, which illustrates that example 2 successfully produced copolymer CP-1-2 using acrylamide, dimethyldiallylammonium chloride and N-vinylpyrrolidone. In the infrared spectrum of copolymer CP-2-2, at 3450cm -1 Near occurrence of-NH 2 Characteristic absorption peak of 3200cm -1 Characteristic absorption peak of-OH in carboxyl appears nearby at 3050cm -1 Characteristic absorption peak of C-H in pyridine ring appears nearby at 1740cm -1 Characteristic absorption peak of c=o in carboxyl group appears nearby at 1680cm -1 Characteristic absorption peak of c=o appears in the vicinity of 1460cm -1 、1440cm -1 The occurrence of a telescopic vibration absorption peak of c=c on pyridine heterocycle in the vicinity indicates that example 6 usesThe copolymer CP-2-2 is successfully prepared from acrylamide, pyridyl quaternary ammonium salt and N-vinyl pyrrolidone. In the infrared spectrum of copolymer CP-3-2, at 3440cm -1 Near occurrence of-NH 2 Characteristic absorption peak of 3200cm -1 Characteristic absorption peak of-OH in carboxyl appears nearby at 3045cm -1 Characteristic absorption peak of C-H in pyridine ring appears nearby, at 1720cm -1 Characteristic absorption peak of c=o in carboxyl group appears nearby at 3420cm -1 Near occurrence of-NH 2 Characteristic absorption peak at 1680cm -1 Characteristic absorption peak of c=o appears nearby, 1475cm -1 、1445cm -1 The occurrence of a telescopic vibration absorption peak of c=c on the pyridine heterocycle nearby suggests that example 10 successfully produced copolymer CP-3-2 using acrylamide and a pyridylammonium salt.
2. Performance test of composite flocculant
2.1 defluorination Performance test of composite flocculant
100mL of simulated fluorine-containing wastewater (prepared by dissolving sodium fluoride in ultrapure water, and having fluoride ion concentration of 10 mg/L) is taken, the composite flocculant of examples 1-15 is added according to the adding amount of 100mg/L, the pH value is regulated to 6.5 by using 1mol/L NaOH solution and 1mol/L HCl solution, then the mixture is stirred and reacted for 30min, and after standing for 2.0h, the mixture is filtered by a 0.22 mu m microporous filter membrane, and the fluoride ion concentration in the filtrate is measured according to the specification of the method for measuring water fluoride-ion selective electrode (GB 7484-87).
FIG. 2 shows the defluorination effect of the composite flocculant, and it can be seen that the composite flocculant has better defluorination performance. It can also be seen that the composite flocculant of example 2 has better defluorination effect than the composite flocculant of example 13, which shows that the composite flocculant made of the copolymer of acrylamide unit, dimethyldiallylammonium chloride unit and N-vinylpyrrolidone unit and polyaluminum chloride has better defluorination performance than the composite flocculant made of the copolymer of acrylamide unit and dimethyldiallylammonium chloride unit and polyaluminum chloride. It can also be seen that the composite flocculants of examples 2, 6 and 10 are superior to the composite flocculants of example 14 in terms of fluorine removal performance, which means that the composite flocculants made of the copolymer consisting of the acrylamide unit, the pyridylammonium salt unit and the N-vinylpyrrolidone unit, and the composite flocculants made of the polyaluminum chloride, the copolymer consisting of the acrylamide unit and the pyridylammonium salt unit, and the composite flocculants made of the polyaluminum chloride are superior to those made of the polyacrylamide polyaluminum chloride. It can also be seen that the composite flocculant of example 4 has better defluorination effect than the composite flocculants of examples 2 and 3, the composite flocculant of example 8 has better defluorination effect than the composite flocculants of examples 6 and 7, and the composite flocculant of example 12 has better defluorination effect than the composite flocculant of examples 10 and 11, which indicates that the composite flocculant has the best defluorination effect on fluorine-containing wastewater when the polyaluminum chloride and polyaluminum ferric silicate are used in combination with the copolymer.
2.2 Effect of coexisting ions on the defluorination Property of composite flocculant
100mL of simulated fluorine-containing wastewater (prepared by dissolving sodium fluoride in ultrapure water, wherein the concentration of fluoride ions is 10mg/L and the concentration of carbonate ions is 500 mg/L) is taken, and the fluorine removal performance test is carried out according to the fluorine removal performance test of the 2.1 composite flocculant.
100mL of simulated fluorine-containing wastewater (prepared by dissolving sodium fluoride in ultrapure water, wherein the concentration of fluorine ions is 10mg/L and the concentration of sulfate ions is 500 mg/L) is taken, and the fluorine removal performance test is carried out according to the fluorine removal performance test of the 2.1 composite flocculant.
100mL of simulated fluorine-containing wastewater (prepared by dissolving sodium fluoride in ultrapure water, wherein the concentration of fluoride ions is 10mg/L and the concentration of phosphate ions is 500 mg/L) is taken, and the fluorine removal performance test is carried out according to the fluorine removal performance test of the 2.1 composite flocculant.
100mL of simulated fluorine-containing wastewater (prepared by dissolving sodium fluoride in ultrapure water, wherein the concentration of fluorine ions is 10mg/L and the concentration of calcium ions is 500 mg/L) is taken, and the fluorine removal performance test is carried out according to the fluorine removal performance test of the 2.1 composite flocculant.
FIG. 3 is a graph showing the effect of coexisting ions on the defluorination properties of composite flocculants, and it can be seen that the presence of carbonate ions and sulfate ions can slightly reduce the defluorination properties of composite flocculants, especially the defluorination rates of the composite flocculants of examples 2 and 14, but has little effect on the defluorination rates of the composite flocculants of examples 6 and 10; the presence of phosphate ions can greatly reduce the fluorine removal rate of the composite flocculant of example 2 and example 14, but has little effect on the fluorine removal rate of the composite flocculant of example 6 and example 10; the presence of calcium ions can improve the fluorine removal rate of the composite flocculant, in particular to improve the fluorine removal rate of the composite flocculant of the example 6 and the example 10; it can be stated above that coexisting ions have little effect on the composite flocculant of example 2 and example 14.
Test example 2:
the fluorine-containing wastewater is treated by adopting a treatment method (example 15) of the fluorine-containing wastewater, wherein the fluorine ion content in the fluorine-containing wastewater is 296.08mg/L, the pH=2.6, and the fluorine ion content in effluent of each stage of sedimentation tanks is shown in table 1. As can be seen from the table 1, when the treatment method of the fluorine-containing wastewater is adopted to treat the fluorine-containing wastewater, the fluorine ion content of the water discharged from the primary sedimentation tank is less than or equal to 30mg/L and the fluorine ion content of the water discharged from the secondary sedimentation tank is less than or equal to 10mg/L under the condition of less composite flocculant; in particular, when the compound flocculant of the examples 6-8 is added and the fluorine ion content in the effluent of the secondary sedimentation tank is less than 1mg/L, the tertiary process can not run. As can also be seen from table 1, the treatment effect of the composite flocculant of example 2 was superior to that of the composite flocculant of example 13, which indicates that the composite flocculant made of the copolymer of acrylamide unit, dimethyldiallylammonium chloride unit and N-vinylpyrrolidone unit and polyaluminum chloride had better defluorination performance than the composite flocculant made of the copolymer of acrylamide unit and dimethyldiallylammonium chloride unit and polyaluminum chloride. As can also be seen from table 1, the treatment effect of the composite flocculants of examples 2, 6 and 10 was superior to that of the composite flocculants of example 14, which indicates that the composite flocculants of acrylamide unit, copolymer of pyridyl quaternary ammonium salt unit and N-vinylpyrrolidone unit and polyaluminum chloride, and the composite flocculants of copolymer of acrylamide unit and pyridyl quaternary ammonium salt unit and polyaluminum chloride were superior in defluorination performance to those of the composite flocculants of polyacrylamide polyaluminum chloride. It can also be seen from table 1 that the treatment effect of the composite flocculant of the addition example 4 is better than that of the composite flocculants of the addition examples 2 and 3, the treatment effect of the composite flocculant of the addition example 8 is better than that of the composite flocculants of the addition examples 6 and 7, and the treatment effect of the composite flocculant of the addition example 12 is better than that of the composite flocculants of the addition examples 10 and 11, which indicates that the composite flocculant has the best treatment effect on fluorine-containing wastewater when the polyaluminum chloride and polyaluminum ferric silicate complex copolymer is used.
TABLE 1 fluorine ion content in the effluent from various stages of settling tanks
Conventional operations in the operation steps of the present invention are well known to those skilled in the art, and are not described herein.
While the foregoing embodiments have been described in detail in connection with the embodiments of the invention, it should be understood that the foregoing embodiments are merely illustrative of the invention and are not intended to limit the invention, and any modifications, additions, substitutions and the like made without departing from the spirit and scope of the invention.
Claims (8)
1. A defluorination composite flocculant is characterized in that: the defluorination composite flocculant comprises a fluorine-removing agent,
-an inorganic flocculant selected from polyaluminum chloride and/or polyaluminum iron; and, a step of, in the first embodiment,
-an organic flocculant, which is a copolymer consisting of acrylamide units and alkenyl quaternary ammonium salt units, or of acrylamide units, alkenyl quaternary ammonium salt units and N-vinylpyrrolidone units; the alkenyl quaternary ammonium salt unit is a pyridyl quaternary ammonium salt unit, and the pyridyl quaternary ammonium salt unit is a pyridyl quaternary ammonium salt unitThe structural formula of the ammonium salt isThe preparation method of the pyridyl quaternary ammonium salt comprises the following steps: adding 3, 5-pyridine dicarboxylic acid and 2-chloroacrylic acid into 50-60v/v% ethanol water solution, stirring uniformly, stirring at 80-110 ℃ for reaction for 24-48h, performing rotary evaporation after the reaction is finished, washing with ethanol for 2-4 times, performing suction filtration, and drying to obtain pyridyl quaternary ammonium salt;
the mass ratio of the inorganic flocculant to the organic flocculant is 100:0.1-10.
2. The defluorination composite flocculant according to claim 1, wherein: the preparation method of the copolymer comprises the following steps: the monomer acrylamide, the pyridyl quaternary ammonium salt and the N-vinyl pyrrolidone are polymerized under the action of an initiator to obtain the copolymer.
3. A defluorination composite flocculant according to claim 2, wherein: the molar ratio of the acrylamide to the pyridyl quaternary ammonium salt to the N-vinyl pyrrolidone is 1:0.1-0.3:0.1-0.3.
4. Use of the defluorinated composite flocculant of claim 1 in the treatment of fluorine-containing wastewater.
5. Use according to claim 4, characterized in that: the application comprises the steps of adding the defluorination composite flocculant into a reaction tank for use.
6. A method for treating fluorine-containing wastewater comprises the following steps,
step 1: the fluorine-containing wastewater enters an adjusting tank, and effluent of the adjusting tank is obtained after homogenizing the uniform quantity;
step 2: feeding the effluent of the regulating tank into a first-stage reaction tank, adding calcium hydroxide and the defluorination composite flocculant according to claim 1 for reaction, and feeding the effluent of the first-stage reaction tank into a first-stage sedimentation tank for mud-water separation to obtain effluent of the first-stage sedimentation tank;
step 3: and (3) after the effluent of the primary sedimentation tank enters a secondary reaction tank, adding the defluorination composite flocculant according to claim 1 for reaction, and performing mud-water separation on the effluent of the secondary reaction tank into the secondary sedimentation tank to obtain the effluent of the secondary sedimentation tank.
7. The method for treating fluorine-containing wastewater according to claim 6, wherein: the adding amount of the defluorination composite flocculant is 10-100mg/L of wastewater.
8. The method for treating fluorine-containing wastewater according to claim 6, wherein: the treatment method of the fluorine-containing wastewater further comprises the following step 4: and (3) after the effluent of the secondary sedimentation tank enters a tertiary reaction tank, adding the defluorination composite flocculant according to claim 1 for reaction, and after the effluent of the tertiary reaction tank enters the tertiary sedimentation tank, performing mud-water separation to obtain the effluent of the tertiary sedimentation tank.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4026794A (en) * | 1976-08-30 | 1977-05-31 | Nalco Chemical Company | Process for resolving oil-in-water emulsions by the use of a cationic polymer and the water soluble salt of an amphoteric metal |
| US4536294A (en) * | 1982-03-23 | 1985-08-20 | Guillet James E | Polymeric flocculants |
| JP2003275503A (en) * | 2002-03-22 | 2003-09-30 | Sanyo Chem Ind Ltd | Polymeric flocculating agent composition |
| CN102627725A (en) * | 2012-04-05 | 2012-08-08 | 西北师范大学 | Synthetic method for cationic polyacrylamide emulsion |
| CN103319654A (en) * | 2013-06-08 | 2013-09-25 | 山东水衡化工有限责任公司 | Synthetic method of cation polyacrylamide flocculating agent |
| CN105967294A (en) * | 2016-06-29 | 2016-09-28 | 江苏奥尼斯环保科技有限公司 | Defluorination flocculation reaction method for fluorine-containing wastewater |
| CN111302465A (en) * | 2020-03-09 | 2020-06-19 | 山东环瑞生态科技有限公司 | Novel liquid defluorination medicament and preparation method and application thereof |
| JP2022020525A (en) * | 2020-07-20 | 2022-02-01 | Ｍｔアクアポリマー株式会社 | Polymer flocculant composition and sludge treatment method using the same |
| CN114804316A (en) * | 2022-05-10 | 2022-07-29 | 北京莱柯倍耳技术有限公司 | All-organic composite flocculant and application thereof |
| CN116639783A (en) * | 2023-06-26 | 2023-08-25 | 中国煤炭地质总局勘查研究总院 | Precipitation treatment process for underground production sewage of coal mine |
-
2023
- 2023-10-09 CN CN202311297165.5A patent/CN117023750B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4026794A (en) * | 1976-08-30 | 1977-05-31 | Nalco Chemical Company | Process for resolving oil-in-water emulsions by the use of a cationic polymer and the water soluble salt of an amphoteric metal |
| US4536294A (en) * | 1982-03-23 | 1985-08-20 | Guillet James E | Polymeric flocculants |
| JP2003275503A (en) * | 2002-03-22 | 2003-09-30 | Sanyo Chem Ind Ltd | Polymeric flocculating agent composition |
| CN102627725A (en) * | 2012-04-05 | 2012-08-08 | 西北师范大学 | Synthetic method for cationic polyacrylamide emulsion |
| CN103319654A (en) * | 2013-06-08 | 2013-09-25 | 山东水衡化工有限责任公司 | Synthetic method of cation polyacrylamide flocculating agent |
| CN105967294A (en) * | 2016-06-29 | 2016-09-28 | 江苏奥尼斯环保科技有限公司 | Defluorination flocculation reaction method for fluorine-containing wastewater |
| CN111302465A (en) * | 2020-03-09 | 2020-06-19 | 山东环瑞生态科技有限公司 | Novel liquid defluorination medicament and preparation method and application thereof |
| JP2022020525A (en) * | 2020-07-20 | 2022-02-01 | Ｍｔアクアポリマー株式会社 | Polymer flocculant composition and sludge treatment method using the same |
| CN114804316A (en) * | 2022-05-10 | 2022-07-29 | 北京莱柯倍耳技术有限公司 | All-organic composite flocculant and application thereof |
| CN116639783A (en) * | 2023-06-26 | 2023-08-25 | 中国煤炭地质总局勘查研究总院 | Precipitation treatment process for underground production sewage of coal mine |
Non-Patent Citations (2)
| Title |
|---|
| 季铵盐型高分子絮凝剂的制备及其在印染废水处理中的应用;隋智慧;赵欣;刘安军;;纺织学报(11);di 24-30页 * |
| 混凝沉淀法处理工业含氟废水的工艺研究;周霖;张彰;方瑜;;化学研究(05);第56-62页 * |
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