CN114426360A - Treatment system and treatment method for high-salinity wastewater in coal chemical industry - Google Patents
Treatment system and treatment method for high-salinity wastewater in coal chemical industry Download PDFInfo
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- CN114426360A CN114426360A CN202010976123.4A CN202010976123A CN114426360A CN 114426360 A CN114426360 A CN 114426360A CN 202010976123 A CN202010976123 A CN 202010976123A CN 114426360 A CN114426360 A CN 114426360A
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- 239000002351 wastewater Substances 0.000 title claims abstract description 93
- 239000000126 substance Substances 0.000 title claims abstract description 74
- 239000003245 coal Substances 0.000 title claims abstract description 61
- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000001728 nano-filtration Methods 0.000 claims abstract description 151
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 57
- 238000002425 crystallisation Methods 0.000 claims abstract description 53
- 230000008025 crystallization Effects 0.000 claims abstract description 53
- 238000001223 reverse osmosis Methods 0.000 claims abstract description 48
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 46
- 238000006243 chemical reaction Methods 0.000 claims abstract description 42
- 238000001914 filtration Methods 0.000 claims abstract description 41
- 238000000108 ultra-filtration Methods 0.000 claims abstract description 40
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims abstract description 39
- 230000003647 oxidation Effects 0.000 claims abstract description 33
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 33
- 230000003197 catalytic effect Effects 0.000 claims abstract description 32
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 23
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 13
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000011575 calcium Substances 0.000 claims abstract description 13
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 13
- 239000011777 magnesium Substances 0.000 claims abstract description 13
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 13
- 238000004062 sedimentation Methods 0.000 claims abstract description 13
- 239000008394 flocculating agent Substances 0.000 claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 193
- 239000012528 membrane Substances 0.000 claims description 56
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 33
- 230000004907 flux Effects 0.000 claims description 24
- 238000011084 recovery Methods 0.000 claims description 24
- 238000004519 manufacturing process Methods 0.000 claims description 23
- 239000010703 silicon Substances 0.000 claims description 22
- 229910052710 silicon Inorganic materials 0.000 claims description 22
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 19
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 claims description 16
- 229910001424 calcium ion Inorganic materials 0.000 claims description 16
- 229910001425 magnesium ion Inorganic materials 0.000 claims description 16
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 claims description 15
- 239000003795 chemical substances by application Substances 0.000 claims description 15
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 14
- 239000011737 fluorine Substances 0.000 claims description 12
- 229910052731 fluorine Inorganic materials 0.000 claims description 12
- 239000007787 solid Substances 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 8
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical group [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 claims description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- 239000001110 calcium chloride Substances 0.000 claims description 7
- 229910001628 calcium chloride Inorganic materials 0.000 claims description 7
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 7
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 6
- 239000000920 calcium hydroxide Substances 0.000 claims description 6
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 6
- 239000003054 catalyst Substances 0.000 claims description 6
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 claims description 5
- 230000014759 maintenance of location Effects 0.000 claims description 5
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 239000012141 concentrate Substances 0.000 claims description 3
- 239000000395 magnesium oxide Substances 0.000 claims description 3
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 3
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims description 2
- 235000019341 magnesium sulphate Nutrition 0.000 claims description 2
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims 1
- 230000010354 integration Effects 0.000 claims 1
- 150000003839 salts Chemical class 0.000 abstract description 35
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 27
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 21
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 20
- 230000000052 comparative effect Effects 0.000 description 17
- 238000005374 membrane filtration Methods 0.000 description 17
- 238000000926 separation method Methods 0.000 description 17
- 238000001704 evaporation Methods 0.000 description 15
- 230000008020 evaporation Effects 0.000 description 15
- -1 fluorine ions Chemical class 0.000 description 14
- 239000003344 environmental pollutant Substances 0.000 description 13
- 231100000719 pollutant Toxicity 0.000 description 13
- 230000000694 effects Effects 0.000 description 11
- 238000001035 drying Methods 0.000 description 9
- 239000000047 product Substances 0.000 description 9
- 238000004064 recycling Methods 0.000 description 8
- 229910052938 sodium sulfate Inorganic materials 0.000 description 8
- 235000011152 sodium sulphate Nutrition 0.000 description 8
- 239000003814 drug Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 239000010802 sludge Substances 0.000 description 6
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 5
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 5
- 239000011780 sodium chloride Substances 0.000 description 5
- 239000013078 crystal Substances 0.000 description 4
- 238000004821 distillation Methods 0.000 description 4
- 239000012510 hollow fiber Substances 0.000 description 4
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 4
- 239000004810 polytetrafluoroethylene Substances 0.000 description 4
- 150000001450 anions Chemical class 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 238000006115 defluorination reaction Methods 0.000 description 3
- 230000018044 dehydration Effects 0.000 description 3
- 238000006297 dehydration reaction Methods 0.000 description 3
- 150000002222 fluorine compounds Chemical class 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 230000035484 reaction time Effects 0.000 description 3
- 150000004760 silicates Chemical class 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 239000003513 alkali Substances 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 239000000701 coagulant Substances 0.000 description 2
- 238000001471 micro-filtration Methods 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- ZFXVRMSLJDYJCH-UHFFFAOYSA-N calcium magnesium Chemical compound [Mg].[Ca] ZFXVRMSLJDYJCH-UHFFFAOYSA-N 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003034 coal gas Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 229920000867 polyelectrolyte Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 230000001502 supplementing effect Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/04—Chlorides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/14—Purification
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/16—Purification
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
- C02F1/16—Treatment of water, waste water, or sewage by heating by distillation or evaporation using waste heat from other processes
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/442—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by nanofiltration
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
- C02F1/5245—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
- C02F1/583—Treatment of water, waste water, or sewage by removing specified dissolved compounds by removing fluoride or fluorine compounds
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
- C02F1/60—Silicon compounds
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/05—Conductivity or salinity
- C02F2209/055—Hardness
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/10—Solids, e.g. total solids [TS], total suspended solids [TSS] or volatile solids [VS]
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- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2303/00—Specific treatment goals
- C02F2303/14—Maintenance of water treatment installations
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/02—Softening water by precipitation of the hardness
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/02—Softening water by precipitation of the hardness
- C02F5/06—Softening water by precipitation of the hardness using calcium compounds
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- Chemical & Material Sciences (AREA)
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- Inorganic Chemistry (AREA)
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- Water Supply & Treatment (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention provides a treatment system for high-salinity wastewater in coal chemical industry, which comprises a pretreatment unit, an ozone catalytic oxidation unit, an ultrafiltration unit, a nanofiltration unit, a reverse osmosis unit and an evaporative crystallization unit, wherein the pretreatment unit comprises a first dosing reaction tank, a second dosing reaction tank, a sedimentation tank and a filtering device which are sequentially connected, the first dosing reaction tank is provided with calcium dosing equipment and magnesium dosing equipment, and the second dosing reaction tank is provided with sodium carbonate dosing equipment, flocculating agent dosing equipment and sodium hydroxide dosing equipment. The invention effectively utilizes the low-temperature heat source and realizes the near zero emission and resource utilization of the high-salinity wastewater in the coal chemical industry. Compared with the prior art, the process provided by the invention has the advantages of good effluent quality, high quality of recycled salts and good technical economy.
Description
Technical Field
The invention relates to the technical field of industrial wastewater treatment, in particular to a treatment system and a treatment method for high-salinity wastewater in coal chemical industry.
Background
The high-salinity wastewater in the coal chemical industry mainly comes from the production process of coal or coal products, such as coal gas washing wastewater, circulating water system drainage, desalted water system drainage, concentrated water of a recycling system and the like. The concentration of Total Dissolved Solids (TDS) in the high-salinity wastewater in the coal chemical industry is usually more than 1%. The high-salinity wastewater in the coal chemical industry is high, and the salt contained in the wastewater is mainly Na+、Ca2+、Mg2+And K+With Cl-、SO4 2-Or F-The salt formed.
In the field of coal chemical industry, the state requires that high-salt-content wastewater generated by enterprises must be strictly treated to realize near zero emission of the wastewater. Part of enterprises generally adopt a combined process of 'pretreatment-membrane concentration-evaporative crystallization' to treat high-salinity wastewater, and NaCl and Na are finally produced2SO4The mixed salt is treated, but the mixed salt is used as dangerous waste and has no good means for realizing reasonable removal. Therefore, in order to really realize the aim of 'salt separation and zero discharge' of the high-salinity wastewater, the method for separating the sodium chloride from the sodium sulfate by different substances is adopted to obtain the separation by different substances, and is the key for really realizing the improvement of the salt separation efficiency of evaporative crystallization and the recycling of salts.
Nanofiltration membranes are functional semipermeable membranes that allow the passage of solvent molecules or certain low molecular mass solutes or low valent ions. In pure water, polyelectrolyte materials of the nanofiltration membrane cause the membrane surface to be intrinsically negative or positive due to the functional group dissociation effect. For electrolyte systems, the anion is in valence stateIn contrast, significant selective rejection is obtained in systems composed of nanofiltration membranes that are intrinsically negative. Generally, monovalent anions (e.g., Cl)-) The salt can permeate the membrane, but the polyvalent anion (such as SO)4 2-) The salt rejection is high. The characteristic of the nanofiltration membrane is utilized to realize the treatment of Cl in the high-salinity wastewater-And SO4 2-The primary separation of the sodium chloride and the sodium sulfate realizes the mass separation and crystallization of the sodium chloride and the sodium sulfate, thereby realizing the recycling of salts.
In addition, with the gradual treatment and concentration in the subsequent process, the content of various pollutants gradually rises, even the pollutants are crystallized and separated out, and the blockage of devices, components, pipelines and the like is caused. Therefore, in order to realize near zero emission of the high-salinity wastewater, pretreatment is required, which is important for reducing pollution and blockage in the subsequent concentration process and ensuring the stable operation of the whole system.
In addition, fluorine element in the raw coal exists in the wastewater in an ionic state, and high concentration fluorine ions are seriously corroded to an evaporator in the concentration and evaporation process, so that the fluorine element needs to be effectively removed before entering an evaporation crystallizer. At present, the wastewater defluorination is usually carried out by a calcium-adding defluorination method, and an effective technical means for the synergy of defluorination and salt separation of the whole process is still lacked.
Chinese patent CN101928087A relates to a method for treating high-salinity wastewater, which adopts the treatment processes of alkali regulation and hardness removal, submerged microfiltration, neutralization and membrane distillation. The conductivity range of the wastewater treated by the method is 3000-10000 mus/cm, the total hardness is 1000-3000 mg/L, the wastewater in the method is treated by adopting the treatment process, and membrane distillation produced water is obtained while high-salinity wastewater is subjected to deep concentration.
Chinese patent CN102936065A also relates to a method for treating wastewater, which also adopts the process flow of alkali-added hardness removal, filtration and vacuum membrane distillation, the treated wastewater system is wastewater with the conductivity of 10000-50000 mu s/cm and the total hardness of 600-1800mg/L, and the conductivity of the wastewater is higher. The hardness of the waste water is removed by adopting sodium hydroxide and sodium carbonate.
Both of the above two patents are directed to high-salinity wastewater with high hardness, and alkali microfiltration is adopted for hardness removal as pretreatment. Moreover, pretreatment does not involve a method for removing various pollutants synergistically, particularly a method for removing fluoride ions. Moreover, no treatment method is provided for the concentrated water problem of membrane distillation, thereby bringing new trouble to the ecological environment.
Disclosure of Invention
In view of the problems existing in the prior art, an object of the present invention is to provide a system for treating high-salinity wastewater in coal chemical industry, which realizes water resource recovery and quality-divided crystallization and resource utilization of salts in wastewater on the basis of effectively treating the high-salinity wastewater in coal chemical industry through cooperation between devices, solves the problem of difficult treatment caused by a large amount of pollutants and high concentration of pollutants in the high-salinity wastewater in coal chemical industry, and realizes near-zero discharge of the high-salinity wastewater in coal chemical industry. Moreover, the system produced water obtained by the treatment system can be directly recycled for supplementing circulating water, so that the advanced treatment and recycling of wastewater are realized, and high-purity sodium sulfate and sodium chloride obtained by the treatment of the method can be recycled as renewable resources.
It is a second object of the present invention to provide a processing method corresponding to the above object.
In order to achieve one of the purposes, the technical scheme adopted by the invention is as follows:
a treatment system of high-salinity wastewater in coal chemical industry comprises:
the pretreatment unit is used for softening, filtering and removing fluorine from the high-salinity wastewater in the coal chemical industry;
the ozone catalytic oxidation unit is connected with the pretreatment unit and is used for removing organic matters in the high-salinity wastewater in the coal chemical industry;
the ultrafiltration unit is connected with the ozone catalytic oxidation unit and is used for removing suspended matters in the high-salinity wastewater in the coal chemical industry and reducing the turbidity of the high-salinity wastewater in the coal chemical industry;
the nanofiltration unit is connected with the ultrafiltration unit and is used for separating chloride and sulfate in the high-salinity wastewater in the coal chemical industry;
the reverse osmosis unit is connected with the nanofiltration unit and is used for concentrating the high-salinity wastewater in the coal chemical industry;
the first evaporative crystallization unit and the second evaporative crystallization unit are respectively connected with the nanofiltration unit and the reverse osmosis unit, the first evaporative crystallization unit is used for crystallizing sulfate in the high-salinity wastewater in the coal chemical industry, and the second evaporative crystallization unit is used for crystallizing chloride in the high-salinity wastewater in the coal chemical industry;
the pretreatment unit comprises a first dosing reaction tank, a second dosing reaction tank, a sedimentation tank and a filtering device which are sequentially connected, wherein the first dosing reaction tank is provided with calcium dosing equipment and magnesium dosing equipment, and the second dosing reaction tank is provided with sodium carbonate dosing equipment, flocculating agent dosing equipment and sodium hydroxide dosing equipment.
According to the invention, when the pretreatment unit provided by the invention is adopted for pretreatment and is combined with the subsequent treatment device provided by the invention for use, a desired treatment effect can be obtained. The technical effects equivalent to those of the present invention cannot be obtained by the pretreatment methods in the prior art, such as CN 108675466A (adding sodium carbonate, sodium hydroxide and crystalline aluminum chloride to the wastewater to be treated), CN 108117222A (adding calcium hydroxide, sodium carbonate, coagulant and coagulant aid to the wastewater to be treated), and the like. Further, omitting any one unit of the subsequent treatment apparatus, for example, omitting the nanofiltration unit, does not achieve the technical effects equivalent to those of the present invention.
According to some embodiments of the present invention, the membrane material used in the filtration device is polytetrafluoroethylene, and the pore size of the membrane is 0.15-0.25 μm.
According to some embodiments of the present invention, the softening is to reduce hardness of the coal chemical industry high salt wastewater.
According to some embodiments of the invention, the purpose of the filtering is to remove particulate matter from the high salinity wastewater of coal chemical industry.
According to some embodiments of the invention, the purpose of the fluorine removal is to remove fluorine ions in the high-salinity wastewater in the coal chemical industry so as to avoid corrosion of subsequent equipment.
In some preferred embodiments of the present invention, the nanofiltration unit employs a two-stage nanofiltration device consisting of a one-stage nanofiltration device and a two-stage nanofiltration device, and preferably, the one-stage nanofiltration device and the two-stage nanofiltration device employ a roll-type nanofiltration membrane module.
In some preferred embodiments of the present invention, the ozone catalytic oxidation unit comprises an ozone generator, an ozone reaction tank filled with a catalyst, and an effluent standing tank.
In some preferred embodiments of the present invention, the ultrafiltration unit employs pressure-type ultrafiltration, and the components are selected from external pressure-type hollow fiber ultrafiltration membrane components.
In some preferred embodiments of the invention, the reverse osmosis unit is selected from a roll-to-roll reverse osmosis membrane module.
In some preferred embodiments of the present invention, the first evaporative crystallization unit is a four-effect evaporative crystallizer.
In some preferred embodiments of the present invention, the second evaporative crystallization unit is a four-effect evaporative crystallizer.
According to some embodiments of the present invention, the first and second evaporative crystallization units may employ waste steam heating as a heat source.
In order to achieve the second purpose, the invention adopts the following technical scheme:
a method for treating high-salinity wastewater in coal chemical industry by using the treatment system comprises the following steps:
s1, introducing the high-salinity wastewater in the coal chemical industry into the pretreatment unit to form a filtration concentrated phase and filtration produced water;
s2, introducing the filtered produced water into the ozone catalytic oxidation unit to form ozone catalytic oxidation effluent;
s3, introducing the effluent of the catalytic oxidation of ozone into the ultrafiltration unit to form ultrafiltration water;
s4, introducing the ultrafiltration water product into the nanofiltration unit to form nanofiltration concentrated water and nanofiltration water product;
s5, introducing the nanofiltration produced water into the reverse osmosis unit so as to form reverse osmosis concentrated water and reverse osmosis produced water;
s6, introducing the nanofiltration concentrated water into the first evaporative crystallization unit to obtain sulfate solid and first evaporative crystallization water;
s7, introducing the reverse osmosis concentrated water into the second evaporative crystallization unit to obtain a chloride solid and second evaporative crystallization water;
wherein, step S1 includes:
a) introducing the coal chemical industry high-salinity wastewater into the first dosing reaction tank, and adding a calcium agent and a magnesium agent into the first dosing reaction tank;
b) overflowing the effluent of the first dosing reaction tank to the second dosing reaction tank, adding sodium carbonate and a flocculating agent into the second dosing reaction tank, and then adding sodium hydroxide;
c) enabling the effluent of the second dosing reaction tank to enter the sedimentation tank;
d) and (c) allowing the sedimentation tank effluent to enter the filtration device, thereby forming the filtration concentrate phase and the filtration product water.
According to some embodiments of the invention, the reverse osmosis produced water, the first evaporative crystallization produced water, and the second evaporative crystallization produced water have conductivities < 1200 μ S/cm, Chemical Oxygen Demand (COD) < 60mg/L, Cl-The concentration is less than 200 mg/L.
According to some embodiments of the invention, the reverse osmosis produced water, the first evaporative crystallization produced water, and the second evaporative crystallization produced water meet circulating water make-up water reuse criteria.
According to some embodiments of the invention, the reverse osmosis produced water, the first evaporative crystallization produced water, and the second evaporative crystallization produced water may be mixed in any manner and recycled for use in the production process or recycled water make-up.
In some preferred embodiments of the present invention, the water quality of the coal chemical industry high-salinity wastewater is characterized by: the pH value is 7.5-8.5; and/or the total soluble solid concentration is 25000 mg/L-35000 mg/L; and/or Cl-The concentration is 3000 mg/L-5000 mg/L; and/or SO4 2-The concentration is 9000 mg/L-12000 mg/L; and/or Mg2+The concentration is 30 mg/L-90 mg/L; and/or Ca2+The concentration is 50 mg/L-150 mg/L; and/or the concentration of dissolved silicon is 50 mg/L-150 mg/L; and/or F-The concentration is 50 mg/L-80 mg/L; and/or HCO3 -The concentration is 300 mg/L-500 mg/L; and/or the chemical oxygen demand is 80 mg/L-120 mg/L.
According to some embodiments of the present invention, the filtered concentrated phase produced in step S1 may be handled in a centralized manner after being solidified by sludge dewatering.
In some preferred embodiments of the invention, the calcium agent is calcium chloride and/or calcium hydroxide.
In some preferred embodiments of the invention, the magnesium agent is selected from one or more of magnesium oxide, magnesium chloride and magnesium sulfate.
In some preferred embodiments of the invention, the flocculating agent is selected from polyaluminium chloride and/or polyferric sulphate.
In some preferred embodiments of the invention, the calcium agent is added in an amount of 0.8g/L to 1.5 g/L.
In some preferred embodiments of the present invention, the magnesium agent is added in an amount of 0.8g/L to 2.0 g/L.
In some preferred embodiments of the invention, the sodium carbonate is added in an amount of 1.0g/L to 1.8 g/L.
In some preferred embodiments of the invention, the flocculant is added in an amount of 0.1g/L to 0.3 g/L.
According to the invention, the unit "g/L" refers to the number of grams of agent added per liter of wastewater.
In some preferred embodiments of the present invention, the sodium hydroxide is added in an amount such that the pH of the wastewater in the second chemical-adding reaction tank is 10.5 to 11.5.
In some preferred embodiments of the present invention, the residence time of the coal chemical industry high-salt wastewater in the first dosing reaction tank and/or the second dosing reaction tank is 5min to 60min, preferably 15min to 30 min.
According to some embodiments of the inventionThe filtering pressure of the filtering device is 0.08MPa to 0.15MPa, and the membrane flux is controlled at 200L/m2·h～400L/m2·h。
According to some embodiments of the invention, the concentration of calcium ions in the filtered product water is less than 10mg/L, the concentration of magnesium ions is less than 10mg/L, the concentration of dissolved silicon is less than 20mg/L, and the concentration of fluoride ions is less than 20 mg/L.
In some preferred embodiments of the present invention, step S4 employs the two-stage nanofiltration device, including:
i) introducing the ultrafiltration water product into the first-stage nanofiltration device to form first-stage nanofiltration concentrated water and first-stage nanofiltration water product;
ii) passing the first-stage nanofiltration concentrated water to the second-stage nanofiltration device, thereby forming the nanofiltration concentrated water and second-stage nanofiltration produced water;
iii) mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production to obtain the nanofiltration water production.
In some preferred embodiments of the invention, the mass ratio of sulfate ions to chloride ions in the nanofiltration concentrated water is (10-20): 1, preferably (15-18): 1.
In some preferred embodiments of the invention, the mass ratio of chloride ions to sulfate radicals in the nanofiltration product water is (40-80): 1, preferably (50-60): 1.
In some preferred embodiments of the present invention, step S4 employs the two-stage nanofiltration device, wherein the operating conditions of the one-stage nanofiltration device include: the operation pressure is 1 MPa-5 MPa, preferably 2 MPa-2.5 MPa, and/or the pH value of the inlet water is 7.0-9.0, preferably 7.5-8.5.
In some preferred embodiments of the present invention, the operating conditions of the two-stage nanofiltration device comprise: the operation pressure is 1.2MPa to 5.5MPa, preferably 2.7MPa to 3.2MPa, and/or the pH value of the inlet water is 7.0 to 9.0, preferably 7.5 to 8.5.
In some preferred embodiments of the present invention, the one-stage nanofiltration device has a membrane flux of 13L/m2·h～20L/m2H, recovery rate of 40% to 60%, preferably 50%.
In some preferred embodiments of the present invention, the membrane flux of the two-stage nanofiltration device is 8L/m2·h～15L/m2H, recovery rate of 40% to 60%, preferably 50%.
In some preferred embodiments of the present invention, the overall recovery of the primary nanofiltration device and the secondary nanofiltration device is 70% to 80%, preferably 75%.
In some preferred embodiments of the present invention, in step S2, the ozone catalytic oxidation unit employs an activated carbon-based catalyst.
In some preferred embodiments of the present invention, the operating conditions of the ozone catalytic oxidation unit include: the pH of the inlet water is 7.0 to 9.0, preferably 7.5 to 8.5.
In some preferred embodiments of the present invention, the operating conditions of the ozone catalytic oxidation unit include: the water inlet temperature is 5-35 ℃, preferably 15-30 ℃.
In some preferred embodiments of the present invention, the operating conditions of the ozone catalytic oxidation unit include: the retention time is 0.1h to 5h, preferably 1h to 2 h.
In some preferred embodiments of the present invention, the operating conditions of the ozone catalytic oxidation unit include: the concentration of ozone is 100 mg/L-250 mg/L, preferably 150 mg/L-200 mg/L.
According to some embodiments of the invention, the COD of the ozone-catalyzed oxidation effluent is from 30mg/L to 60 mg/L.
In some preferred embodiments of the present invention, in step S3, the filtration pressure of the ultrafiltration unit is 0.05MPa to 0.15MPa, preferably 0.08MPa to 0.12 MPa.
In some preferred embodiments of the present invention, in step S5, the operating conditions of the reverse osmosis unit include: the operating pressure is 1MPa to 5MPa, preferably 2MPa to 3 MPa.
In some preferred embodiments of the present invention, in step S5, the operating conditions of the reverse osmosis unit include: the pH of the inlet water is 7.0 to 9.0, preferably 7.5 to 8.5.
In some preferred embodiments of the inventionIn one embodiment, the reverse osmosis unit has a membrane flux of 13L/m2·h～18L/m2H, recovery rate is 55% -65%.
According to some embodiments of the present invention, the evaporative crystallization operations in step S6 and step S7 are conventional operations in the art, and may be performed in any manner known in the art, which is not a focus of the present invention and is not described herein.
According to some embodiments of the present invention, the evaporative crystallization operations in step S6 and in step S7 may employ a low temperature heat source, such as waste heat steam.
According to some embodiments of the present invention, in step S6, the purity of the obtained sulfate, such as sodium sulfate, after separation and drying, is more than 98%, and reaches class ii first-class standard in GB/T6009-2014.
According to some embodiments of the present invention, in step S7, the obtained chloride, such as sodium chloride salt, is separated and dried to have a purity of 98% or more, which meets the primary standard of refined industrial salt in the standard GB/T5462-2015 "industrial salt".
The substantial difference between the present invention and the prior art is: aiming at the technical defects of the prior art, the high-salinity wastewater in the coal chemical industry is treated by adopting high-efficiency hard-removing filtration, ozone catalytic oxidation, ultrafiltration, nanofiltration, reverse osmosis and evaporative crystallization. Compared with the prior art, the process provided by the invention has the advantages of good effluent quality, high quality of recycled salts and good technical economy.
The beneficial effects are as follows:
1. the invention adopts the high-efficiency hardness removal filtering process to treat the pollutants such as hardness and the like in the high-salinity wastewater in the coal chemical industry, can effectively remove the calcium, magnesium, silicon and fluorine pollutants and other suspended matters in the wastewater in one step through the optimization of the dosing process and the dosing formula, and has the advantages of good treatment effect, excellent effluent water quality, simple equipment, high automation degree, easy operation and maintenance, strong environment adaptability and small occupied area;
2. the invention adopts two-stage nanofiltration to separate the quality and the salt of the high-salinity wastewater in the coal chemical industry, fully exerts the technical advantages of nanofiltration, improves the salt separation effect of the nanofiltration process through the optimized design of the nanofiltration process, and realizes the high-efficiency separation of the salt in the high-salinity wastewater in the coal chemical industry;
3. the invention further concentrates the nanofiltration produced water by adopting roll-type reverse osmosis, further improves the salt content of the nanofiltration produced water, reduces the treatment scale of subsequent evaporative crystallization and reduces the operation cost.
4. The invention adopts the four-effect evaporation technology to treat the two-stage nanofiltration concentrated water and the roll type reverse osmosis concentrated water, fully utilizes the low-temperature heat source of a factory, and reduces the operation cost;
5. the method provided by the invention is adopted to carry out quality-divided crystallization on the coal chemical industry high-salinity wastewater, so that the problem of difficult treatment caused by a plurality of pollutants and high concentration of the pollutants in the coal chemical industry high-salinity wastewater is solved, the near zero emission of the coal chemical industry high-salinity wastewater is realized, and the resource utilization of water resources and salts is realized.
Drawings
FIG. 1 is a process flow diagram of example 1 of the present invention.
Detailed Description
The present invention will be described in detail below with reference to examples, but the scope of the present invention is not limited to the following description.
The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available from commercial sources.
Example 1
The main water quality characteristics of the coal chemical industry high salt waste water that handles in this example are: pH 7.5, Total Dissolved Solids (TDS) concentration 25000mg/L, Cl-In a concentration of 3000mg/L, SO4 2-In a concentration of 9000Mg/L, Mg2+Has a concentration of 30mg/L, Ca2+Has a concentration of 50mg/L, a concentration of dissolved silicon of 50mg/L, F-Has a concentration of 50mg/L, HCO3 -The concentration of (A) was 300mg/L and the concentration of COD was 80 mg/L.
The process flow is shown in figure 1, and comprises the following specific steps:
step 1, treating the high-salinity wastewater in the coal chemical industry in a high-efficiency hardness removal filtering unit (namely a pretreatment unit). Firstly, adding calcium chloride and magnesium chloride into a first-stage dosing reaction tank, wherein the adding concentration is 0.8g/L, the reaction time is 15min, the effluent overflows into a second-stage dosing reaction tank, sodium carbonate and polyaluminium chloride are added, the adding concentration of the sodium carbonate is 1.0g/L, and the adding concentration of the polyaluminium chloride is 0.1 g/L; then adding sodium hydroxide, adjusting the pH value of the wastewater to 10.8, reacting for 15min, allowing the effluent to enter a primary sedimentation tank to generate hard calcium, hard magnesium, silicates, fluorides and complexes thereof and other various precipitates, and allowing the effluent of the primary sedimentation tank to enter a membrane filtration unit to form high-efficiency hardness-removing filtered effluent; the filtering pressure of the membrane filtering unit is 0.08MPa, the membrane material is polytetrafluoroethylene, and the membrane aperture is 0.15 mu m; solidifying the filter residues and then carrying out centralized treatment;
under the condition, the membrane flux of the membrane filtration unit is controlled at 400L/m2H is about; the Suspended Substance (SS) of the effluent of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is less than 10mg/L, the magnesium ion concentration is less than 10mg/L, the dissolved silicon concentration is less than 20mg/L, and the fluorine ion concentration is less than 20 mg/L;
step 2, the high-efficiency hardness removal filtration produced water enters an ozone catalytic oxidation unit for treatment, the ozone catalytic oxidation unit adopts an active carbon-based catalyst, and the operation conditions are as follows: the pH value of inlet water is 7.5, the inlet water temperature is 15 ℃, the retention time is 1h, and the ozone concentration is 150 mg/L.
Under the condition, the COD of the effluent of the ozone catalytic oxidation unit is about 30 mg/L;
step 3, the effluent of the catalytic oxidation of ozone enters an ultrafiltration unit for treatment, the ultrafiltration unit adopts pressure type ultrafiltration, an external pressure type hollow fiber ultrafiltration membrane component is adopted as the component, and the filtration pressure is 0.08 MPa;
under the condition, the turbidity of the ultrafiltration produced water is less than 0.1 NTU; the concentrated phase of ultrafiltration is treated by centralized transportation after sludge dehydration and solidification;
step 4, the ultrafiltration produced water enters a first-stage nanofiltration unit for treatment, and the first-stage nanofiltration concentrated water enters a second-stage nanofiltration unit for treatment, so that first-stage nanofiltration produced water, second-stage nanofiltration produced water and second-stage nanofiltration concentrated water are finally formed; wherein, the operating conditions of the two-stage nanofiltration are respectively as follows: and (3) first-stage nanofiltration: the operation pressure is 2MPa, and the pH value of inlet water is 7.5; and (3) two-stage nanofiltration: the operation pressure is 2.7MPa, and the pH value of inlet water is 7.5;
under the condition, the membrane flux of the first-stage nanofiltration is 17-20L/m2H, recovery 50%; the membrane flux of the two-stage nanofiltration is 13-15L/m2H, recovery 50%; the overall recovery rate of the two sections is 75 percent; mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, wherein the mass ratio of chloride ions to sulfate ions in the water is 60: 1; the mass ratio of sulfate ions to chloride ions in the two-stage nanofiltration concentrated water is 18: 1;
step 5, mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, and then treating the mixture in a roll type reverse osmosis unit to form reverse osmosis water production and reverse osmosis concentrated water; the operation conditions of the roll type reverse osmosis unit are as follows: the operation pressure is 2MPa, and the pH value of inlet water is 7.5;
under the condition, the membrane flux of the roll type reverse osmosis unit is 16-18L/m2H, recovery 65%;
step 6, the concentrated water of the second-stage nanofiltration enters an evaporation crystallization unit to be subjected to evaporation crystallization treatment to obtain sodium sulfate salts and evaporation crystallization water, and the obtained sodium sulfate salt is separated and dried to obtain sodium sulfate salt with the purity of more than 98 percent and reaches class II first-class standard in GB/T6009-2014 Standard of Industrial anhydrous sodium sulfate;
and 7, carrying out evaporative crystallization treatment on the reverse osmosis concentrated water in an evaporative crystallization unit to obtain sodium chloride salts and evaporative crystallization produced water, wherein the purity of the obtained sodium chloride salts is more than 98% after separation and drying, and the obtained sodium chloride salts reach the primary standard of refined industrial salt in GB/T5462-2015 Industrial salt standards.
Wherein, the water conductivity of the reverse osmosis produced water and the evaporated crystal produced water after being mixed is less than 1200 mu S/cm, the COD is less than 60mg/L, and the Cl is-Less than 200mg/L, and meets the water replenishing and recycling requirements of recycled circulating water.
Example 2
The main water quality characteristics of the coal chemical industry high salt waste water that handles in this example are: pH 8, TDS concentration 30000mg/L, Cl-In a concentration of 4000mg/L, SO4 2-Has a concentration of 10000Mg/L, Mg2+Has a concentration of 60mg/L, Ca2+Has a concentration of 100mg/L, dissolved silicon concentration of 100mg/L, F-Has a concentration of 60mg/L, HCO3 -The concentration of (A) was 400mg/L and the concentration of COD was 100 mg/L.
The method comprises the following specific steps:
step 1, treating the high-salinity wastewater in the coal chemical industry in a high-efficiency hardness removal filtering unit. Firstly, adding calcium chloride and magnesium chloride into a first-stage dosing reaction tank, wherein the adding concentrations are 1.1g/L and 1.5g/L respectively, the reaction time is 20min, effluent overflows into a second-stage dosing reaction tank, sodium carbonate and polyaluminium chloride are added, the adding concentration of the sodium carbonate is 1.5g/L, and the adding concentration of the polyaluminium chloride is 0.2 g/L; then adding sodium hydroxide, adjusting the pH value of the wastewater to 11.2, reacting for 20min, allowing the effluent to enter a primary sedimentation tank to generate hard calcium, hard magnesium, silicates, fluorides and complexes thereof and other various precipitates, and allowing the effluent of the primary sedimentation tank to enter a filtering unit to form high-efficiency hardness-removing filtered effluent; the filtering pressure of the membrane filtering unit is 0.12MPa, the membrane material is polytetrafluoroethylene, and the membrane aperture is 0.2 mu m; solidifying the filter residues and then carrying out centralized treatment;
under the condition, the membrane flux of the membrane filtration unit is controlled at 300L/m2H is about; the SS of effluent of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is less than 10mg/L, the magnesium ion concentration is less than 10mg/L, the concentration of dissolved silicon is less than 20mg/L, and the concentration of fluorine ions is less than 20 mg/L;
step 2, the high-efficiency hardness removal filtration produced water enters an ozone catalytic oxidation unit for treatment, the ozone catalytic oxidation unit adopts an active carbon-based catalyst, and the operation conditions are as follows: the pH value of inlet water is 8, the inlet water temperature is 20 ℃, the retention time is 1.5h, and the ozone concentration is 170 mg/L.
Under the condition, COD of the effluent of the ozone catalytic oxidation is about 40 mg/L;
step 3, the effluent of the catalytic oxidation of ozone enters an ultrafiltration unit for treatment, the ultrafiltration unit adopts pressure type ultrafiltration, an external pressure type hollow fiber ultrafiltration membrane component is adopted as the component, and the filtration pressure is 0.1 MPa;
under the condition, the turbidity of the ultrafiltration produced water is less than 0.1 NTU; the concentrated phase of ultrafiltration is treated by centralized transportation after sludge dehydration and solidification;
step 4, the ultrafiltration produced water enters a first-stage nanofiltration unit for treatment, and the first-stage nanofiltration concentrated water enters a second-stage nanofiltration unit for treatment, so that first-stage nanofiltration produced water, second-stage nanofiltration produced water and second-stage nanofiltration concentrated water are finally formed; wherein, the operating conditions of the two-stage nanofiltration are respectively as follows: and (3) first-stage nanofiltration: the operation pressure is 2.3MPa, and the pH value of inlet water is 8; and (3) two-stage nanofiltration: the operation pressure is 3.0MPa, and the pH value of inlet water is 8;
under the condition, the membrane flux of the first-stage nanofiltration is 16-18L/m2H, recovery 50%; the membrane flux of the two-stage nanofiltration is 10-13L/m2H, recovery 50%; the overall recovery rate of the two sections is 75 percent; mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, wherein the mass ratio of chloride ions to sulfate ions in the water is 55: 1; the mass ratio of sulfate ions to chloride ions in the two-stage nanofiltration concentrated water is 16: 1;
step 5, mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, and then treating the mixture in a roll type reverse osmosis unit to form reverse osmosis water production and reverse osmosis concentrated water; the operation conditions of the roll type reverse osmosis unit are as follows: the operation pressure is 2.5MPa, and the pH value of inlet water is 8;
under the condition, the membrane flux of the roll type reverse osmosis unit is 14-16L/m2H, recovery rate 60%;
step 6, the concentrated water of the second-stage nanofiltration enters an evaporation crystallization unit to be subjected to evaporation crystallization treatment to obtain sodium sulfate salts and evaporation crystallization water, and the obtained sodium sulfate salt is separated and dried to obtain sodium sulfate salt with the purity of more than 98 percent and reaches class II first-class standard in GB/T6009-2014 Standard of Industrial anhydrous sodium sulfate;
and 7, carrying out evaporative crystallization treatment on the reverse osmosis concentrated water in an evaporative crystallization unit to obtain sodium chloride salts and evaporative crystallization produced water, wherein the purity of the obtained sodium chloride salts is more than 98% after separation and drying, and the obtained sodium chloride salts reach the primary standard of refined industrial salt in GB/T5462-2015 Industrial salt standards.
Wherein, the water conductivity of the reverse osmosis produced water and the evaporated crystal produced water after being mixed is less than 1200 mu S/cm, the COD is less than 60mg/L, and the Cl is-Less than 200mg/L, and meets the water replenishing and recycling requirements of recycled circulating water.
Example 3
The main water quality characteristics of the coal chemical industry high salt waste water that handles in this example are: the pH value is 8.5, and the pH value is,the concentration of Total Dissolved Solids (TDS) was 35000mg/L, Cl-Has a concentration of 5000mg/L, SO4 2-In a concentration of 12000Mg/L, Mg2+Has a concentration of 90mg/L, Ca2+Has a concentration of 150mg/L, a concentration of dissolved silicon of 150mg/L, F-Has a concentration of 80mg/L, HCO3 -The concentration of (A) was 500mg/L and the concentration of COD was 120 mg/L.
The method comprises the following specific steps:
step 1, treating the high-salinity wastewater in the coal chemical industry in a high-efficiency hardness removal filtering unit. Firstly, adding calcium hydroxide and magnesium oxide into a first-stage dosing reaction tank, wherein the adding concentrations are 1.5g/L and 2.0g/L respectively, the reaction time is 30min, effluent overflows into a second-stage dosing reaction tank, sodium carbonate and polyaluminium chloride are added, the adding concentration of the sodium carbonate is 1.8g/L, and the adding concentration of the polyaluminium chloride is 0.3 g/L; then adding sodium hydroxide, adjusting the pH value of the wastewater to 11.5, reacting for 30min, allowing the effluent to enter a primary sedimentation tank to generate hard calcium, hard magnesium, silicates, fluorides and complexes thereof and other various precipitates, and allowing the effluent of the primary sedimentation tank to enter a filtering unit to form high-efficiency hardness-removing filtered effluent; the filtering pressure of the membrane filtering unit is 0.15MPa, the membrane material is polytetrafluoroethylene, and the membrane aperture is 0.25 mu m; solidifying the filter residues and then carrying out centralized treatment;
under the condition, the membrane flux of the membrane filtration unit is controlled at 200L/m2H is about; the SS of effluent of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is less than 10mg/L, the magnesium ion concentration is less than 10mg/L, the concentration of dissolved silicon is less than 20mg/L, and the concentration of fluorine ions is less than 20 mg/L;
step 2, the high-efficiency hardness removal filtration produced water enters an ozone catalytic oxidation unit for treatment, the ozone catalytic oxidation unit adopts an active carbon-based catalyst, and the operation conditions are as follows: the pH value of the inlet water is 8.5, the inlet water temperature is 30 ℃, the retention time is 2h, and the ozone concentration is 200 mg/L.
Under the condition, COD of the effluent of the ozone catalytic oxidation is about 60 mg/L;
step 3, the effluent of the catalytic oxidation of ozone enters an ultrafiltration unit for treatment, the ultrafiltration unit adopts pressure type ultrafiltration, an external pressure type hollow fiber ultrafiltration membrane component is adopted as the component, and the filtration pressure is 0.12 MPa;
under the condition, the turbidity of the ultrafiltration produced water is less than 0.1 NTU; the concentrated phase of ultrafiltration is treated by centralized transportation after sludge dehydration and solidification;
step 4, the ultrafiltration produced water enters a first-stage nanofiltration unit for treatment, and the first-stage nanofiltration concentrated water enters a second-stage nanofiltration unit for treatment, so that first-stage nanofiltration produced water, second-stage nanofiltration produced water and second-stage nanofiltration concentrated water are finally formed; wherein, the operating conditions of the two-stage nanofiltration are respectively as follows: and (3) first-stage nanofiltration: the operation pressure is 2.5MPa, and the pH value of inlet water is 8.5; and (3) two-stage nanofiltration: the operation pressure is 3.2MPa, and the pH value of inlet water is 8.5;
under the condition, the membrane flux of the first-stage nanofiltration is 13-15L/m2H, recovery 50%; the membrane flux of the two-stage nanofiltration is 8-10L/m2H, recovery 50%; the overall recovery rate of the two sections is 75 percent; mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, wherein the mass ratio of chloride ions to sulfate ions in the water is 50: 1; the mass ratio of sulfate ions to chloride ions in the two-stage nanofiltration concentrated water is 15: 1;
step 5, mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production, and then treating the mixture in a roll type reverse osmosis unit to form reverse osmosis water production and reverse osmosis concentrated water; the operation conditions of the roll type reverse osmosis unit are as follows: the operation pressure is 3MPa, and the pH value of inlet water is 8.5;
under the condition, the membrane flux of the roll type reverse osmosis unit is 13-15L/m2H, recovery of 55%;
step 6, the concentrated water of the second-stage nanofiltration enters an evaporation crystallization unit to be subjected to evaporation crystallization treatment to obtain sodium sulfate salts and evaporation crystallization water, and the obtained sodium sulfate salt is separated and dried to obtain sodium sulfate salt with the purity of more than 98 percent and reaches class II first-class standard in GB/T6009-2014 Standard of Industrial anhydrous sodium sulfate;
and 7, carrying out evaporative crystallization treatment on the reverse osmosis concentrated water in an evaporative crystallization unit to obtain sodium chloride salts and evaporative crystallization produced water, wherein the purity of the obtained sodium chloride salts is more than 98% after separation and drying, and the obtained sodium chloride salts reach the primary standard of refined industrial salt in GB/T5462-2015 Industrial salt standards.
Wherein, the water conductivity of the reverse osmosis produced water and the evaporated crystal produced water after being mixed is less than 1200 mu S/cm, the COD is less than 60mg/L, and the Cl is-＜200mgand/L, meeting the water replenishing and recycling requirements of recycled circulating water.
Example 4 (comparative)
Example 4 was set up substantially the same as example 1, except that the nanofiltration apparatus used in step 4 of example 4 was a single-stage nanofiltration apparatus, and the operating conditions of the single-stage nanofiltration apparatus included: the operation pressure is 2.7MPa, and the pH value of inlet water is 7.5; under the condition, the membrane flux of the first-stage nanofiltration is 10-16L/m2H, recovery 65%; the mass ratio of chloride ions to sulfate ions in the first-stage nanofiltration produced water is 40: 1; the mass ratio of sulfate ions to chloride ions in the first-stage nanofiltration concentrated water is 11: 1; the recovery rate of the first-stage nanofiltration cannot reach the recovery rate of the two-stage nanofiltration process, and the membrane flux at the later stage of the first-stage nanofiltration is seriously reduced to only 10L/m2·h。
Under the condition, after the treatment of the subsequent steps 5-7, the purity of the obtained sodium sulfate salt is about 83 percent after separation and drying, the purity of the sodium chloride salt is about 92 percent after separation and drying, and the salt purity is lower than that of the salt after the two-stage nanofiltration process.
Wherein, the water conductivity of the reverse osmosis produced water and the evaporated crystal produced water after being mixed is less than 1200 mu S/cm, the COD is less than 60mg/L, and the Cl is-Less than 200mg/L, and meets the water replenishing and recycling requirements of recycled circulating water.
Example 5 (comparative)
Example 5 was set up to be substantially the same as example 1 except that sodium hydroxide was added to adjust the pH of the wastewater to 10.0 in example 5. Under the pH condition, the effluent Suspended Substance (SS) of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is 40mg/L, the magnesium ion concentration is 27mg/L, the silicon concentration is 42mg/L, and the F-concentration is 33 mg/L. It can be seen that when the pH value is adjusted to 10.0, the removal effect of various pollutants is poor, the water inlet condition of the subsequent unit cannot be achieved, and if the subsequent treatment is performed forcibly, the scaling and corrosion of the subsequent system can be caused, and the stable operation of the membrane unit and the quality of the subsequent crystallized salt are seriously affected.
Example 6 (comparative)
Example 6 was set up essentially the same as example 1 except that in example 6 sodium hydroxide was added to adjust the pH of the wastewater to 9.5, at which pH the membrane filtration unit effluent suspension (SS) was less than 0.5mg/L, the effluent calcium ion concentration was 47mg/L, the magnesium ion concentration was 29mg/L, the dissolved silicon concentration was 48mg/L, and the F-concentration was 38 mg/L. It can be seen that when the pH value is adjusted to 9.5, various pollutants are not removed basically, the treatment function of the unit is not achieved, the water inlet condition of a subsequent unit cannot be met, and if the subsequent treatment is performed forcibly, the scaling and corrosion of a subsequent system can be caused, and the stable operation of a membrane unit and the quality of subsequent crystallized salt are seriously influenced.
Example 7 (comparative)
Example 7 was set up to be essentially the same as example 1, except that in example 7 sodium hydroxide was added to adjust the pH of the wastewater to 12.0, at which pH the effluent suspension (SS) of the membrane filtration unit was less than 0.5mg/L, the effluent calcium magnesium ion concentration was less than 10mg/L, the dissolved silicon concentration was less than 20mg/L, and the fluoride ion concentration was less than 20 mg/L; it can be seen that the pH value is adjusted from 11.5 to 12 by continuously adding the medicament, and the removal effect of various pollutants is not changed, so that the continuous adding of the medicament only can increase the medicament consumption, improve the treatment cost, bring more pollutants to the water body, indirectly increase the treatment cost of the subsequent sludge and increase the subsequent treatment difficulty.
Comparative example 1
Comparative example 1 was set up to be substantially the same as example 1 except that the pretreatment apparatus of comparative example 1 was composed of a reaction tank, a precipitation tank and a membrane filtration unit, and accordingly, step 1 of comparative example 1 was:
the coal chemical industry high-salinity wastewater enters a reaction tank, calcium chloride, magnesium chloride, sodium carbonate, polyaluminium chloride and sodium hydroxide are added into the reaction tank, wherein the adding concentration of the calcium chloride and the magnesium chloride is 0.8g/L, the adding concentration of the sodium carbonate is 1.0g/L, the adding concentration of the polyaluminium chloride is 0.1g/L, the pH value of the wastewater is adjusted to be 10.8 by the sodium hydroxide, and the reaction is carried out for 45 min. The subsequent steps correspond to example 1.
Under the condition, the membrane flux of the membrane filtration unit is controlled at 200L/m2H is about; membrane filtration unit outletThe SS of the water is less than 0.5mg/L, the calcium ion concentration of the effluent is about 12mg/L, the magnesium ion concentration is about 10mg/L, the silicon concentration of the effluent is about 27mg/L, and the fluorine ion concentration is 35 mg/L. The removal effect of the discharged water-soluble silicon is poor, the higher silicon-soluble silicon can cause the scaling of a subsequent nanofiltration system, and the cleaning period of the nanofiltration system and the sodium sulfate evaporation crystallizer is shortened. Meanwhile, the purity of the sodium sulfate salt after separation and drying is 96.8 percent and is slightly lower than that of the sodium sulfate salt in the example 1.
In fact, the research finds that under the same water quality condition, the dosage of the medicament is saved by adopting two-stage reaction dosing compared with the dosage of the medicament which is added by adopting one stage. Therefore, in the comparative example, if the reasonable removal of the dissolved silicon is ensured, the adding amount of the medicaments such as calcium chloride, magnesium chloride, sodium carbonate and the like needs to be increased by at least more than 1.2 times, the adding cost of the medicaments is increased, and the subsequent sludge treatment cost is also increased.
Comparative example 2
Comparative example 2 was set to be substantially the same as comparative example 1 except that the agents added in comparative example 2 were sodium carbonate, sodium hydroxide and polyaluminum chloride, wherein the sodium carbonate was added at a concentration of 1.0g/L, the polyaluminum chloride was added at a concentration of 0.1g/L, and the sodium hydroxide adjusted the pH of the wastewater to 10.8, and reacted for 45 min. The subsequent steps correspond to example 1.
Under the condition, the membrane flux of the membrane filtration unit is controlled at 200L/m2H is about; the SS of effluent of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is about 12mg/L, the magnesium ion concentration is about 10mg/L, the silicon concentration of effluent is about 45mg/L, and the fluorine ion concentration is 45 mg/L. The removal effect of the discharged water-soluble silicon and fluorine ions is poor, the subsequent nanofiltration system is scaled, and the cleaning period of the nanofiltration system and the sodium sulfate evaporation crystallizer is shortened. Meanwhile, the purity of the sodium sulfate salt after separation and drying is 96.3 percent and is slightly lower than that of the sodium sulfate salt in the example 1.
Comparative example 3
Comparative example 3 was set to be substantially the same as comparative example 1 except that the agents added in comparative example 3 were sodium carbonate, calcium hydroxide and polyaluminum chloride, wherein the sodium carbonate was added at a concentration of 1.0g/L, the polyaluminum chloride was added at a concentration of 0.1g/L, and the calcium hydroxide adjusted the pH of the wastewater to 10.8, and reacted for 45 min. The subsequent steps correspond to example 1.
Under the condition, the membrane flux of the membrane filtration unit is controlled at 200L/m2H is about; the SS of effluent of the membrane filtration unit is less than 0.5mg/L, the calcium ion concentration of the effluent is about 18mg/L, the magnesium ion concentration is about 8mg/L, the silicon concentration of effluent is about 48mg/L, and the fluorine ion concentration is 32 mg/L. The removal effect of calcium ions, dissolved silicon and fluorine ions in the effluent is poor, the scaling of a subsequent nanofiltration system is caused, and the cleaning period of the nanofiltration system and a sodium sulfate evaporation crystallizer is shortened. Meanwhile, the purity of the sodium sulfate salt after separation and drying is 95.5 percent, which is lower than that of the sodium sulfate salt in the example 1.
It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.
Claims (10)
1. A treatment system of high-salinity wastewater in coal chemical industry comprises:
the pretreatment unit is used for softening, removing silicon and fluorine and filtering the high-salinity wastewater in the coal chemical industry;
the ozone catalytic oxidation unit is connected with the pretreatment unit and is used for removing organic matters in the high-salinity wastewater in the coal chemical industry;
the ultrafiltration unit is connected with the ozone catalytic oxidation unit and is used for removing suspended matters in the high-salinity wastewater in the coal chemical industry and reducing the turbidity of the high-salinity wastewater in the coal chemical industry;
the nanofiltration unit is connected with the ultrafiltration unit and is used for separating chloride and sulfate in the high-salinity wastewater in the coal chemical industry;
the reverse osmosis unit is connected with the nanofiltration unit and is used for concentrating the high-salinity wastewater in the coal chemical industry;
the first evaporative crystallization unit and the second evaporative crystallization unit are respectively connected with the nanofiltration unit and the reverse osmosis unit, the first evaporative crystallization unit is used for crystallizing sulfate in the high-salinity wastewater in the coal chemical industry, and the second evaporative crystallization unit is used for crystallizing chloride in the high-salinity wastewater in the coal chemical industry;
the pretreatment unit comprises a first dosing reaction tank, a second dosing reaction tank, a sedimentation tank and a filtering device which are sequentially connected, wherein the first dosing reaction tank is provided with calcium dosing equipment and magnesium dosing equipment, and the second dosing reaction tank is provided with sodium carbonate dosing equipment, flocculating agent dosing equipment and sodium hydroxide dosing equipment.
2. The treatment system according to claim 1, wherein the nanofiltration unit employs a two-stage nanofiltration apparatus consisting of a first-stage nanofiltration device and a second-stage nanofiltration device, and preferably, the first-stage nanofiltration device and the second-stage nanofiltration device employ roll-type nanofiltration membrane modules.
3. A method for treating high-salinity wastewater in coal chemical industry by using the treatment system of claim 1 or 2, comprising the following steps:
s1, introducing the high-salinity wastewater in the coal chemical industry into the pretreatment unit to form a filtration concentrated phase and filtration produced water;
s2, introducing the filtered produced water into the ozone catalytic oxidation unit to form ozone catalytic oxidation effluent;
s3, introducing the effluent of the catalytic oxidation of ozone into the ultrafiltration unit to form ultrafiltration water;
s4, introducing the ultrafiltration water product into the nanofiltration unit to form nanofiltration concentrated water and nanofiltration water product;
s5, introducing the nanofiltration produced water into the reverse osmosis unit so as to form reverse osmosis concentrated water and reverse osmosis produced water;
s6, introducing the nanofiltration concentrated water into the first evaporative crystallization unit to obtain sulfate solid and first evaporative crystallization water;
s7, introducing the reverse osmosis concentrated water into the second evaporative crystallization unit to obtain a chloride solid and second evaporative crystallization water;
wherein, step S1 includes:
a) introducing the coal chemical industry high-salinity wastewater into the first dosing reaction tank, and adding a calcium agent and a magnesium agent into the first dosing reaction tank;
b) overflowing the effluent of the first dosing reaction tank to the second dosing reaction tank, adding sodium carbonate and a flocculating agent into the second dosing reaction tank, and then adding sodium hydroxide;
c) enabling the effluent of the second dosing reaction tank to enter the sedimentation tank;
d) and (c) allowing the sedimentation tank effluent to enter the filtration device, thereby forming the filtration concentrate phase and the filtration product water.
4. The method as claimed in claim 3, wherein the water quality characteristics of the coal chemical industry high-salinity wastewater are as follows: the pH value is 7.5-8.5; and/or the total soluble solid concentration is 25000 mg/L-35000 mg/L; and/or Cl-The concentration is 3000 mg/L-5000 mg/L; and/or SO4 2-The concentration is 9000 mg/L-12000 mg/L; and/or Mg2+The concentration is 30 mg/L-90 mg/L; and/or Ca2+The concentration is 50 mg/L-150 mg/L; and/or the concentration of dissolved silicon is 50 mg/L-150 mg/L; and/or F-The concentration is 50 mg/L-80 mg/L; and/or HCO3 -The concentration is 300 mg/L-500 mg/L; and/or the chemical oxygen demand is 80 mg/L-120 mg/L.
5. The method according to claim 3 or 4, wherein the calcium agent is calcium chloride and/or calcium hydroxide; the magnesium agent is selected from one or more of magnesium oxide, magnesium chloride and magnesium sulfate; the flocculating agent is selected from polyaluminium chloride and/or polyferric sulfate; preferably, the addition amount of the calcium agent is 0.8 g/L-1.5 g/L; the addition amount of the magnesium agent is 0.8 g/L-2.0 g/L; the addition amount of the sodium carbonate is 1.0 g/L-1.8 g/L; the addition amount of the flocculant is 0.1-0.3 g/L; the adding amount of the sodium hydroxide is such that the pH value of the wastewater in the second dosing reaction tank is 10.5-11.5, and further preferably, the retention time of the high-salt wastewater in the coal chemical industry in the first dosing reaction tank and/or the second dosing reaction tank is 5-60 min, preferably 15-30 min.
6. The method according to any one of claims 3 to 5, wherein step S4 employs the two-stage nanofiltration apparatus comprising:
i) introducing the ultrafiltration water product into the first-stage nanofiltration device to form first-stage nanofiltration concentrated water and first-stage nanofiltration water product;
ii) passing the first-stage nanofiltration concentrated water to the second-stage nanofiltration device, thereby forming the nanofiltration concentrated water and second-stage nanofiltration produced water;
iii) mixing the first-stage nanofiltration water production and the second-stage nanofiltration water production to obtain the nanofiltration water production;
preferably, the mass ratio of sulfate ions to chloride ions in the nanofiltration concentrated water is (10-20): 1, preferably (15-18): 1; and/or the mass ratio of chloride ions to sulfate radicals in the nanofiltration produced water is (40-80): 1, preferably (50-60): 1.
7. The method according to any one of claims 3-6, wherein step S4 employs the two-stage nanofiltration apparatus, wherein the operating conditions of the one-stage nanofiltration device include: the operation pressure is 1MPa to 5MPa, preferably 2MPa to 2.5MPa, and/or the pH value of inlet water is 7.0 to 9.0, preferably 7.5 to 8.5; the operating conditions of the two-stage nanofiltration device comprise: the operation pressure is 1.2MPa to 5.5MPa, preferably 2.7MPa to 3.2MPa, and/or the pH value of inlet water is 7.0 to 9.0, preferably 7.5 to 8.5; preferably, the membrane flux of the one-stage nanofiltration device is 13L/m2·h～20L/m2H, the recovery rate is 40-60%, preferably 50%; and/or the membrane flux of the two-stage nanofiltration device is 8L/m2·h～15L/m2H, the recovery rate is 40-60%, preferably 50%; more preferably, the integration of the first-stage nanofiltration device and the second-stage nanofiltration deviceThe recovery rate is 70-80%, preferably 75%.
8. The method according to any one of claims 4 to 7, wherein in step S2, the ozone catalytic oxidation unit employs an activated carbon-based catalyst; and/or the operating conditions of the ozone catalytic oxidation unit comprise: the pH value of the inlet water is 7.0-9.0, preferably 7.5-8.5, and/or the inlet water temperature is 5-35 ℃, preferably 15-30 ℃, and/or the residence time is 0.1-5 h, preferably 1-2 h, and/or the ozone concentration is 100-250 mg/L, preferably 150-200 mg/L.
9. The method according to any of claims 4 to 8, wherein in step S3, the filtration pressure of the ultrafiltration unit is between 0.05MPa and 0.15MPa, preferably between 0.08MPa and 0.12 MPa.
10. The method according to any one of claims 4 to 9, wherein in step S5, the operating conditions of the reverse osmosis unit include: the operation pressure is 1MPa to 5MPa, preferably 2MPa to 3MPa, and/or the pH value of inlet water is 7.0 to 9.0, preferably 7.5 to 8.5; preferably, the membrane flux of the reverse osmosis unit is 13L/m2·h～18L/m2H, recovery rate is 55% -65%.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115231775A (en) * | 2022-07-26 | 2022-10-25 | 山东鲁抗中和环保科技有限公司 | Method for treating pharmaceutical chemical high-salinity wastewater |
| CN115536195A (en) * | 2022-09-21 | 2022-12-30 | 宝钢工程技术集团有限公司 | Cooling water treatment system for reducing temperature of coal gas and using method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009101157A1 (en) * | 2008-02-14 | 2009-08-20 | Otv Sa | Process for treating water by a nanofiltration or reverse osmosis membrane system permitting high conversion rates due to the elimination of organic matter |
| CN204625408U (en) * | 2015-03-20 | 2015-09-09 | 英诺伟霆（北京）环保技术有限公司 | A kind of strong brine reduction treatment system |
| CN105502782A (en) * | 2015-12-07 | 2016-04-20 | 湖南湘牛环保实业有限公司 | Technology for recovering water resources and salt from coking wastewater in coal chemical industry |
| US20180148350A1 (en) * | 2016-11-29 | 2018-05-31 | China Petroleum & Chemical Corporation | Method and System for Treating Brine Waste Water |
| CN110606612A (en) * | 2019-11-04 | 2019-12-24 | 江苏中电创新环境科技有限公司 | Coal coking high-salinity wastewater recycling treatment process |
-
2020
- 2020-09-16 CN CN202010976123.4A patent/CN114426360A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009101157A1 (en) * | 2008-02-14 | 2009-08-20 | Otv Sa | Process for treating water by a nanofiltration or reverse osmosis membrane system permitting high conversion rates due to the elimination of organic matter |
| CN204625408U (en) * | 2015-03-20 | 2015-09-09 | 英诺伟霆（北京）环保技术有限公司 | A kind of strong brine reduction treatment system |
| CN105502782A (en) * | 2015-12-07 | 2016-04-20 | 湖南湘牛环保实业有限公司 | Technology for recovering water resources and salt from coking wastewater in coal chemical industry |
| US20180148350A1 (en) * | 2016-11-29 | 2018-05-31 | China Petroleum & Chemical Corporation | Method and System for Treating Brine Waste Water |
| CN110606612A (en) * | 2019-11-04 | 2019-12-24 | 江苏中电创新环境科技有限公司 | Coal coking high-salinity wastewater recycling treatment process |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115231775A (en) * | 2022-07-26 | 2022-10-25 | 山东鲁抗中和环保科技有限公司 | Method for treating pharmaceutical chemical high-salinity wastewater |
| CN115536195A (en) * | 2022-09-21 | 2022-12-30 | 宝钢工程技术集团有限公司 | Cooling water treatment system for reducing temperature of coal gas and using method thereof |
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