CN111333219A - Online purification and recycling method of PCB washing wastewater - Google Patents
Online purification and recycling method of PCB washing wastewater Download PDFInfo
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- CN111333219A CN111333219A CN202010166980.8A CN202010166980A CN111333219A CN 111333219 A CN111333219 A CN 111333219A CN 202010166980 A CN202010166980 A CN 202010166980A CN 111333219 A CN111333219 A CN 111333219A
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- 239000002351 wastewater Substances 0.000 title claims abstract description 79
- 238000005406 washing Methods 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000000746 purification Methods 0.000 title claims abstract description 20
- 238000004064 recycling Methods 0.000 title claims abstract description 18
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 75
- 229910052802 copper Inorganic materials 0.000 claims abstract description 75
- 239000010949 copper Substances 0.000 claims abstract description 75
- 239000012528 membrane Substances 0.000 claims abstract description 40
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 claims abstract description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 34
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 31
- 239000007788 liquid Substances 0.000 claims abstract description 22
- 238000010521 absorption reaction Methods 0.000 claims abstract description 17
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 16
- 239000002253 acid Substances 0.000 claims abstract description 14
- 238000006481 deamination reaction Methods 0.000 claims abstract description 13
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 12
- 230000009615 deamination Effects 0.000 claims abstract description 12
- 150000003863 ammonium salts Chemical class 0.000 claims abstract description 9
- QKSIFUGZHOUETI-UHFFFAOYSA-N copper;azane Chemical compound N.N.N.N.[Cu+2] QKSIFUGZHOUETI-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000000701 coagulant Substances 0.000 claims abstract description 7
- 150000002500 ions Chemical class 0.000 claims abstract description 4
- 239000002244 precipitate Substances 0.000 claims abstract description 4
- 239000012266 salt solution Substances 0.000 claims abstract description 3
- 239000007787 solid Substances 0.000 claims abstract description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 45
- 239000000243 solution Substances 0.000 claims description 31
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 26
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 claims description 18
- 229910001431 copper ion Inorganic materials 0.000 claims description 18
- 235000011121 sodium hydroxide Nutrition 0.000 claims description 15
- 229920002401 polyacrylamide Polymers 0.000 claims description 14
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims description 13
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims description 13
- 235000011130 ammonium sulphate Nutrition 0.000 claims description 13
- 238000005530 etching Methods 0.000 claims description 12
- 238000003756 stirring Methods 0.000 claims description 11
- 238000004140 cleaning Methods 0.000 claims description 9
- 230000008021 deposition Effects 0.000 claims description 8
- 238000005189 flocculation Methods 0.000 claims description 8
- 230000016615 flocculation Effects 0.000 claims description 8
- 239000006227 byproduct Substances 0.000 claims description 7
- 239000003153 chemical reaction reagent Substances 0.000 claims description 7
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 6
- 229910052979 sodium sulfide Inorganic materials 0.000 claims description 6
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 claims description 6
- 239000003513 alkali Substances 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 5
- ZURAKLKIKYCUJU-UHFFFAOYSA-N copper;azane Chemical compound N.[Cu+2] ZURAKLKIKYCUJU-UHFFFAOYSA-N 0.000 claims description 5
- 239000011790 ferrous sulphate Substances 0.000 claims description 5
- 235000003891 ferrous sulphate Nutrition 0.000 claims description 5
- 229910001385 heavy metal Inorganic materials 0.000 claims description 5
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims description 5
- 229910000359 iron(II) sulfate Inorganic materials 0.000 claims description 5
- 125000001741 organic sulfur group Chemical group 0.000 claims description 5
- 239000011148 porous material Substances 0.000 claims description 5
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 4
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 4
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 4
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims description 4
- 239000000725 suspension Substances 0.000 claims description 4
- 229910052793 cadmium Inorganic materials 0.000 claims description 3
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 3
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 claims description 3
- 229910052753 mercury Inorganic materials 0.000 claims description 3
- 239000004254 Ammonium phosphate Substances 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 2
- 229940037003 alum Drugs 0.000 claims description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 2
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 claims description 2
- 235000019270 ammonium chloride Nutrition 0.000 claims description 2
- 229910000148 ammonium phosphate Inorganic materials 0.000 claims description 2
- 235000019289 ammonium phosphates Nutrition 0.000 claims description 2
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 2
- 239000000920 calcium hydroxide Substances 0.000 claims description 2
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 2
- 239000000292 calcium oxide Substances 0.000 claims description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 2
- 239000002738 chelating agent Substances 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims description 2
- MNNHAPBLZZVQHP-UHFFFAOYSA-N diammonium hydrogen phosphate Chemical compound [NH4+].[NH4+].OP([O-])([O-])=O MNNHAPBLZZVQHP-UHFFFAOYSA-N 0.000 claims description 2
- 238000001035 drying Methods 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 2
- 229920001495 poly(sodium acrylate) polymer Polymers 0.000 claims description 2
- CHWRSCGUEQEHOH-UHFFFAOYSA-N potassium oxide Chemical compound [O-2].[K+].[K+] CHWRSCGUEQEHOH-UHFFFAOYSA-N 0.000 claims description 2
- 229910001950 potassium oxide Inorganic materials 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 2
- KKCBUQHMOMHUOY-UHFFFAOYSA-N sodium oxide Chemical compound [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims description 2
- 229910001948 sodium oxide Inorganic materials 0.000 claims description 2
- NNMHYFLPFNGQFZ-UHFFFAOYSA-M sodium polyacrylate Chemical compound [Na+].[O-]C(=O)C=C NNMHYFLPFNGQFZ-UHFFFAOYSA-M 0.000 claims description 2
- 239000011593 sulfur Substances 0.000 claims description 2
- 229910052717 sulfur Inorganic materials 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 description 14
- 239000000203 mixture Substances 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 4
- 239000010802 sludge Substances 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 239000003344 environmental pollutant Substances 0.000 description 3
- 231100000719 pollutant Toxicity 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 239000006228 supernatant Substances 0.000 description 3
- 239000005749 Copper compound Substances 0.000 description 2
- 150000001880 copper compounds Chemical class 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- -1 ammonia ions Chemical class 0.000 description 1
- MXZRMHIULZDAKC-UHFFFAOYSA-L ammonium magnesium phosphate Chemical compound [NH4+].[Mg+2].[O-]P([O-])([O-])=O MXZRMHIULZDAKC-UHFFFAOYSA-L 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000002306 biochemical method Methods 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000013505 freshwater Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 239000002920 hazardous waste Substances 0.000 description 1
- 239000008235 industrial water Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000000618 nitrogen fertilizer Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 229910052567 struvite Inorganic materials 0.000 description 1
- FZUJWWOKDIGOKH-UHFFFAOYSA-N sulfuric acid hydrochloride Chemical compound Cl.OS(O)(=O)=O FZUJWWOKDIGOKH-UHFFFAOYSA-N 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Images
Classifications
-
- 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
- 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
-
- 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
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
-
- 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
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/20—Heavy metals or heavy metal compounds
-
- C—CHEMISTRY; METALLURGY
- 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
- C02F2103/346—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from semiconductor processing, e.g. waste water from polishing of wafers
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- 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
Abstract
The invention relates to an online purification and recycling method of PCB washing wastewater, which comprises the steps of ⑴ adding a copper removing agent under an alkaline condition to break the complex ion of copper ammonia in the PCB washing wastewater to generate copper-containing precipitate, ⑵ adding a coagulant to separate solid and liquid and remove copper and recycle copper resources, ⑶ leading the ammonia nitrogen wastewater after copper removal to pass through a deamination membrane system containing an acid absorption liquid, leading free ammonia molecules to react with the acid absorption liquid in the membrane system to generate ammonium salt solution, and recycling the washing water after purification.
Description
Technical Field
The invention relates to the field of sewage treatment, in particular to an online purification and recycling method of PCB washing wastewater.
Background
Alkaline etching is a commonly used process in Printed Circuit Board (PCB) production, and produces a large amount of dark blue alkaline board washing water (water washing wastewater) containing copper ammonia complex and free ammonia in the subsequent washing process. The wastewater contains copper ions and ammonia nitrogen with higher concentration, wherein the contents of copper and ammonia nitrogen are respectively 2000mg/L and 5000mg/L, and most of the copper ions and ammonia nitrogen exist in the solution in the form of copper-ammonia complex. The conventional ammonia nitrogen treatment means such as a stripping/stripping method, a magnesium ammonium phosphate method (MAP method), an electrolysis method, a breakpoint chlorine adding method, a biochemical method and the like are adopted to treat the wastewater with great difficulty and high cost. The method for removing ammonia nitrogen in water by utilizing a gaseous membrane separation technology is widely applied to the fields of chemical pharmacy, smelting and the like at present, can remove and recover ammonia nitrogen in waste water and waste liquid at normal temperature and normal pressure, has very strict requirements on impurity components in the ammonia nitrogen waste water, often needs a complex pretreatment impurity removal means, and is difficult to treat the medium-high concentration copper ammonia complex waste water. Therefore, almost all related enterprises can not effectively treat the wastewater at present, and only the wastewater can be fully mixed with a large amount of other types of wastewater for comprehensive treatment. However, the mixed wastewater has more complex water quality condition, greatly increases the comprehensive treatment cost and the burden of the subsequent treatment process: on one hand, a large amount of various medicaments are consumed, a large amount of copper-containing hazardous waste sludge is generated, and the water consumption and the treatment cost of production enterprises are increased; on the other hand, because the copper and ammonia nitrogen in the wastewater are not completely removed, the wastewater discharge exceeds the standard and potential environmental hazards are caused.
With the stricter requirements of the country on environmental protection, the ecological environment department of China clearly requires that PCB production enterprises meet the requirements of clean production, the cleaning efficiency and the water reuse rate are improved, the wastewater production amount is reduced, and the wastewater is encouraged to be recycled after being treated according to the requirements of the production process. The printed circuit board industry standard condition published by the Ministry of industry and credibility in 2019 indicates that the wastewater production index should reach the level of the second grade of the clean production standard-printed circuit board manufacturing industry, and encourages to obtain the level of the first grade or above, so that the industrial water reuse rate is more than or equal to 55%, and the metal copper recovery rate is more than or equal to 95%.
Therefore, if the pollutants such as copper, ammonia nitrogen and the like in the wastewater can be separated and removed in a targeted manner, the pollution problem can be solved from the source, the wastewater treatment cost is reduced, the wastewater discharge can be reduced, and the water utilization rate in the production process is improved. At present, no invention or report example for on-line purification and reuse of PCB washing water after alkaline etching by adopting a precipitation method copper-gas film deamination synergistic treatment technology is found at home and abroad.
Disclosure of Invention
The invention aims to provide a novel copper-ammonia complex-reaction diffusion balance theory-based novel copper-ammonia recovery-deamination cooperative treatment technical method, solves the problem that high-concentration copper and ammonia nitrogen pollutants in the discharge of cleaning wastewater after the existing PCB alkaline etching exceed standards, can efficiently recover valuable resources such as copper, ammonia nitrogen and the like in the wastewater, improves the water resource utilization rate of the process by recycling the wastewater after purification, and has great significance for realizing pollution reduction from the source and clean production.
The technical scheme of the invention is that the on-line purification and recycling method of PCB washing wastewater is characterized by comprising the following steps:
⑴ adding copper removing agent under alkaline condition to break the complex of copper ammonia complex ion in PCB washing wastewater to generate copper-containing precipitate;
⑵ adding coagulant to separate solid and liquid to remove copper and recover copper resource;
⑶, the ammonia nitrogen wastewater after copper removal passes through a deamination membrane system containing acid absorption liquid, so that free ammonia molecules react with the acid absorption liquid in the membrane system to generate ammonium salt solution, and the purified washing water can be recycled.
Preferably, the step ⑴ further comprises adding the cuprammonium complex solution into a complex breaking and copper precipitation processor, adding sodium sulfide or organic sulfur reagent with the copper content of 1.0-1.2 times, adjusting the pH value to be more than 11 by using 30-35% sodium hydroxide solution, and rapidly stirring for reaction for 30min to obtain the copper-containing suspension.
Preferably, the PCB washing wastewater in the step ⑴ is copper-ammonium complex wastewater generated by an alkaline etching process cleaning system, the copper ion content is 100 mg/L-2000 mg/L, the ammonia nitrogen content is 500 mg/L-5000 mg/L, and the initial pH value is 8.5-9.5;
the copper removing agent in the step ⑴ is selected from one or more of alkali or inorganic sulfur reagent, organic sulfur reagent and heavy metal chelating agent, and the dosage of the copper removing agent is 0.1-10 times, preferably 1-3 times of the copper content in the wastewater;
the copper removing agent in the step ⑴ is used for adjusting the pH value of the wastewater to 10-13, preferably 11-13, and the agent used for adjusting the pH value is one or more of sodium hydroxide, sodium oxide, sodium carbonate, potassium hydroxide, potassium oxide, calcium hydroxide and calcium oxide, preferably sodium hydroxide.
Preferably, the step ⑵ further comprises:
(2.1) transferring the copper-containing suspension into a flocculation settler, adding 50-100 mg/L PAC or 100mg/L ferrous sulfate and 10mg/L PAM or 10mg/L hydrolyzed polyacrylamide, slowly stirring for 1-2 min, and standing for settlement;
(2.2) settling underflow to obtain high-content copper mud, taking out the high-content copper mud, dehydrating and drying to obtain high-purity copper-containing compound powder, and overflowing to obtain ammonia nitrogen wastewater.
Preferably, the coagulant in step ⑵ is one or more selected from aluminum sulfate, ferrous sulfate, ferric chloride, aluminum chloride, alum, polyaluminum chloride, polyferric chloride sulfate, polyacrylamide, hydrolyzed polyacrylamide and sodium polyacrylate, and the amount of the coagulant is 0.1-0.0005%, preferably 0.05-0.001% of the amount of the wastewater.
Preferably, the step ⑶ further comprises:
(3.1) the settled overflow is subjected to precision filtration through the aperture of 1-5 microns and then enters a gaseous membrane system containing acid absorption liquid for deamination; trapping free ammonia molecules in water by 15-20% dilute sulfuric acid on the other side of the membrane to form an ammonium sulfate solution;
and (3.2) recycling the overflow after qualified multistage membrane treatment in the deamination membrane system, wherein the copper ion content in the wastewater treated by the membrane system is 0.2-5 mg/L, and the ammonia nitrogen content is 5-50 mg/L.
Preferably, the concentration of suspended matters in the clear solution after copper removal in the step ⑶ is not higher than 50mg/L, preferably not higher than 5mg/L before the clear solution enters a deamination membrane system, and the pore diameter of a used precision filter is less than or equal to 5 mu m, preferably less than or equal to 1 mu m;
the acid-containing absorption liquid in the step ⑶ is one or more of sulfuric acid, phosphoric acid and hydrochloric acid, the ammonium salt is one or more of ammonium sulfate, ammonium phosphate and ammonium chloride, and the concentration is 5-40%, preferably 15-30%.
Preferably, the method comprises the following steps: when the sulfuric acid is used as absorption liquid, the copper content in the obtained copper byproduct is 63.8 percent, and the purity is about 97 percent; the concentration of ammonium sulfate in the ammonium salt byproduct is 18.9 percent, heavy metals of lead, cadmium and mercury are not detected, and the content of copper is less than 0.5 mg/L.
Preferably, the method comprises the following steps: the PCB washing wastewater is subjected to purification treatment and then returns to the alkaline etching washing process for recycling, so that the new water consumption of a cleaning system is reduced; the PCB washing wastewater directly enters an alkali blending pool of a wastewater station for recycling after being purified, so that the consumption of new water and the addition of flake caustic soda are saved.
Compared with the prior art, the invention has the beneficial effects that:
⑴ the invention can solve the problem of ammonia nitrogen and copper pollution of waste water, after the waste water is treated by advanced copper removal and multistage membrane deamination with high efficiency by a precipitation method, the ammonia nitrogen concentration of the outlet water can be lower than 15mg/L, the copper is lower than 0.5mg/L, and the invention can be flexibly regulated and controlled according to the requirement, thereby ensuring that the waste water in the factory can reach the standard and be discharged without affecting the normal production.
⑵ the invention has high sludge reduction and resource recovery rate in the treatment process, the copper content in the by-product obtained by the copper deposition of the wastewater under the alkaline condition can reach more than 60%, compared with the dangerous waste copper sludge with the copper content generally lower than 5% produced by the conventional precipitation method, the sludge amount is obviously reduced, the added value is obviously improved, the high-purity ammonium salt generated after the ammonia in the wastewater is efficiently captured by the acid absorption liquid can be returned to the production process or used for manufacturing nitrogenous fertilizer, and no secondary pollution such as extra waste residue, waste liquid, waste gas and the like exists.
⑶ the invention can save water, and the waste water can be reused after copper removal, deamination and purification treatment, thereby reducing the addition of fresh water in related procedures and saving water by over 90%.
⑷ the invention has safe and economic operation, fully utilizes the water quality characteristics of the waste water and the advantages of the cooperative treatment technology, has simple flow, less medicament addition and high utilization rate, and the system operates at the normal temperature and the normal pressure, has low energy consumption, is not used, does not generate toxic and harmful substances, and has safe and economic integral operation.
Drawings
FIG. 1 is a schematic diagram of the principles of the present invention;
FIG. 2 is a schematic process flow diagram of the present invention.
Detailed Description
The invention will be further described in detail with reference to the following examples:
referring to fig. 1, based on the solubility product difference of copper compounds and the chemical reaction equilibrium theory, the dissolved copper ammonia complex ions in the wastewater are converted into non-soluble copper compound precipitates under alkaline conditions by adjusting the pH value and adding a copper removing agent, and then are removed by coagulation separation, and free ammonia molecules are released; then, free ammonia molecules are automatically transferred from the wastewater side of the membrane to the acid absorption liquid side based on gasification concentration difference diffusion in the deamination membrane system, and react with the acid absorption liquid to be converted into ammonia ions, so that the removal of ammonia nitrogen pollutants at the wastewater side and the recovery of ammonia nitrogen resources at the acid absorption liquid side are realized.
Example 1
Referring to fig. 2, a self-made copper ammonium complex solution with copper ion content of 100mg/L, ammonia nitrogen content of 1000mg/L and initial pH of 9 is added into a complex breaking copper deposition processor, sodium sulfide with 1.0 time of copper content is added, pH is adjusted to be more than 11 by 30% sodium hydroxide solution, and the mixture is rapidly stirred and reacted for 30 min; transferring the solution into a flocculation settler, adding 50mg/L PAC and 10mg/L PAM, slowly stirring for 1min, and standing for settling; the supernatant fluid enters a membrane system (4-stage treatment) after passing through a precision filter with the aperture of 5 mu m, and free ammonia molecules in the water are trapped by 15 percent dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 1.6mg/L, and the ammonia nitrogen content is 35 mg/L.
Example 2
Referring to fig. 2, a self-made copper ammonium complex solution with copper ion content of 100mg/L, ammonia nitrogen content of 1000mg/L and initial pH of 9 is added into a complex breaking copper deposition processor, sodium sulfide with 1.2 times of copper content is added, pH is adjusted to be more than 11 by 30% sodium hydroxide solution, and the mixture is rapidly stirred and reacted for 30 min; transferring the solution into a flocculation settler, adding 50mg/L PAC and 10mg/L PAM, slowly stirring for 1min, standing for settling, allowing the supernatant to pass through a precision filter with a pore size of 1 μm, allowing the supernatant to enter a membrane system (5-stage treatment), and collecting free ammonia molecules in water by 15% dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 0.2mg/L, and the ammonia nitrogen content is 14 mg/L.
Example 3
Referring to fig. 2, adding final-stage washing water of an alkaline etching section of a printed circuit board factory, which contains 660mg/L of copper ions, 2450mg/L of ammonia nitrogen and 8.8 of initial pH, into a decomplexation copper deposition processor, adding 1.0 time of sodium sulfide containing copper, adjusting the pH to be more than 11 by using 35% sodium hydroxide solution, and rapidly stirring for reaction for 30 min; transferring the solution into a flocculation settler, adding 80mg/L PAC and 10mg/L PAM, slowly stirring for 1min, standing for settling, overflowing the settler through a precision filter with a pore size of 5 mu m, then entering a membrane system (5-stage treatment), and trapping free ammonia molecules in water by 15% dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 1.2mg/L, and the ammonia nitrogen content is 45 mg/L.
Example 4
Referring to fig. 2, final-stage washing water of an alkaline etching section of a printed circuit board factory, which contains 500mg/L of copper ions, 1500mg/L of ammonia nitrogen and initial pH of 9.1, is added into a complex breaking and copper deposition processor, pH is adjusted to be more than 11 by 30% sodium hydroxide solution, organic sulfur reagent with 1.0 time of copper content is added, and the mixture is rapidly stirred and reacts for 30 min; transferring the solution into a flocculation settler, adding 100mg/L PAC and 10mg/L PAM, slowly stirring for 1min, and standing for settling; the overflow of the settler passes through a precision filter with the aperture of 1 mu m and then enters a membrane system (5-stage treatment), and free ammonia molecules in water are trapped by 15 percent dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 0.3mg/L, and the ammonia nitrogen content is 12 mg/L.
Example 5
Referring to fig. 2, alkaline etching final-stage washing water with a copper ion content of 250mg/L, an ammonia nitrogen content of 1100mg/L and an initial pH of 8.8 is added into a complex breaking copper deposition processor, a 30% sodium hydroxide solution is used to adjust the pH to be more than 12, then sodium sulfide with a copper content of 1.0 time is added, and the mixture is rapidly stirred and reacted for 30 min; transferring the solution into a flocculation settler, adding 100mg/L PAC and 10mg/L PAM, slowly stirring for 2min, and standing for settlement; the overflow of the settler passes through a precision filter with the aperture of 1 mu m and then enters a membrane system (6-stage treatment), and free ammonia molecules in water are trapped by 20 percent dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 0.2mg/L, and the ammonia nitrogen content is 7 mg/L.
Example 6
Referring to fig. 2, alkaline etching final-stage washing water with copper ion content of 220mg/L, ammonia nitrogen content of 1060mg/L and initial pH of 8.8 is added into a complex breaking copper deposition processor, pH is adjusted to be greater than 12 by 30% sodium hydroxide solution, and the mixture is rapidly stirred and reacted for 30 min; then transferring the solution into a flocculation settler, adding 100mg/L ferrous sulfate and 10mg/L hydrolyzed polyacrylamide, slowly stirring for 2min, and standing for sedimentation; the overflow of the settler passes through a precision filter with the aperture of 1 mu m and then enters a membrane system (6-stage treatment), and free ammonia molecules in water are trapped by 15 percent dilute sulfuric acid on the other side of a membrane to form an ammonium sulfate solution; the copper ion content in the wastewater treated by the membrane system is 0.2mg/L, and the ammonia nitrogen content is 7 mg/L.
Example 7
Referring to FIG. 2, the copper by-product obtained by using sulfuric acid as the absorption liquid has a copper content of 63.8% and a purity of about 97%; the ammonium sulfate concentration in the ammonium salt byproduct is 18.9 percent, heavy metals of lead, cadmium and mercury are not detected, and the copper content is less than 0.5 mg/.
Example 8
Referring to fig. 2, the PCB cleaning wastewater is purified and then returned to the alkaline etching cleaning process for recycling, so as to reduce the consumption of new water in the cleaning system.
Example 9
Referring to fig. 2, the PCB board washing wastewater is purified and then directly enters the alkali blending tank of the wastewater station for reuse, so as to save the consumption of new water and the addition of caustic soda flakes.
The above-mentioned embodiments are only preferred embodiments of the present invention, and all equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.
Claims (9)
1. An on-line purification and recycling method of PCB washing wastewater is characterized by comprising the following steps:
⑴ adding copper removing agent under alkaline condition to break the complex of copper ammonia complex ion in PCB washing wastewater to generate copper-containing precipitate;
⑵ adding coagulant to separate solid and liquid to remove copper and recover copper resource;
⑶, the ammonia nitrogen wastewater after copper removal passes through a deamination membrane system containing acid absorption liquid, so that free ammonia molecules react with the acid absorption liquid in the membrane system to generate ammonium salt solution, and the purified washing water can be recycled.
2. The on-line purification and reuse method of PCB washing wastewater according to claim 1,
the step ⑴ further comprises adding the copper-ammonium complex solution into a complex breaking copper deposition processor, adding sodium sulfide or organic sulfur reagent with the copper content of 1.0-1.2 times, adjusting the pH value to be more than 11 by using 30-35% sodium hydroxide solution, and rapidly stirring for reaction for 30min to obtain the copper-containing suspension.
3. The on-line purification and reuse method of PCB washing wastewater according to claim 1,
the PCB washing wastewater in the step ⑴ is copper ammonium complex wastewater generated by an alkaline etching process cleaning system, the copper ion content is 100 mg/L-2000 mg/L, the ammonia nitrogen content is 500 mg/L-5000 mg/L, and the initial pH value is 8.5-9.5;
the copper removing agent in the step ⑴ is selected from one or more of alkali or inorganic sulfur reagent, organic sulfur reagent and heavy metal chelating agent, and the dosage of the copper removing agent is 0.1-10 times, preferably 1-3 times of the copper content in the wastewater;
the copper removing agent in the step ⑴ is used for adjusting the pH value of the wastewater to 10-13, preferably 11-13, and the agent used for adjusting the pH value is one or more of sodium hydroxide, sodium oxide, sodium carbonate, potassium hydroxide, potassium oxide, calcium hydroxide and calcium oxide, preferably sodium hydroxide.
4. The method for on-line purification and recycling of PCB washing wastewater of claim 1, wherein the step ⑵ further comprises:
(2.1) transferring the copper-containing suspension into a flocculation settler, adding 50-100 mg/L PAC or 100mg/L ferrous sulfate and 10mg/L PAM or 10mg/L hydrolyzed polyacrylamide, slowly stirring for 1-2 min, and standing for settlement;
(2.2) settling underflow to obtain high-content copper mud, taking out the high-content copper mud, dehydrating and drying to obtain high-purity copper-containing compound powder, and overflowing to obtain ammonia nitrogen wastewater.
5. The on-line purification and recycling method of PCB washing wastewater according to claim 1, wherein the coagulant in step ⑵ is one or more selected from aluminum sulfate, ferrous sulfate, ferric chloride, aluminum chloride, alum, polyaluminum chloride, polyferric sulfate polychloride, polyacrylamide, hydrolyzed polyacrylamide, and sodium polyacrylate, and the amount of the coagulant is 0.1% -0.0005% of the amount of wastewater, preferably 0.05% -0.001%.
6. The method for on-line purification and recycling of PCB washing wastewater of claim 1, wherein the step ⑶ further comprises:
(3.1) filtering the settled overflow through a 1-5 mu m pore size precision filter, and then, sending the overflow into a gaseous membrane system containing acid absorption liquid to deaminate; trapping free ammonia molecules in water by 15-20% dilute sulfuric acid on the other side of the membrane to form an ammonium sulfate solution;
and (3.2) recycling the overflow after qualified multistage membrane treatment in the deamination membrane system, wherein the copper ion content in the wastewater treated by the membrane system is 0.2-5 mg/L, and the ammonia nitrogen content is 5-50 mg/L.
7. The on-line purification and reuse method of PCB washing wastewater according to claim 1,
the concentration of suspended matters in the clear solution after copper removal in the step ⑶ is not higher than 50mg/L, preferably not higher than 5mg/L before the clear solution enters a deamination membrane system, and the pore diameter of a used precision filter is not more than 5 mu m, preferably not more than 1 mu m;
the acid-containing absorption liquid in the step ⑶ is one or more of sulfuric acid, phosphoric acid and hydrochloric acid, the ammonium salt is one or more of ammonium sulfate, ammonium phosphate and ammonium chloride, and the concentration is 5-40%, preferably 15-30%.
8. The on-line purification and reuse method of PCB washing wastewater according to claim 7, wherein when said sulfuric acid is used as absorption liquid, copper content in copper by-product is 63.8%, and purity is about 97%; the concentration of ammonium sulfate in the ammonium salt byproduct is 18.9 percent, heavy metals of lead, cadmium and mercury are not detected, and the content of copper is less than 0.5 mg/L.
9. The on-line purification and reuse method of PCB washing wastewater according to claim 1, wherein the PCB washing wastewater is subjected to purification treatment and then returns to the alkaline etching washing procedure for recycling, so as to reduce the new water consumption of the cleaning system; after being purified, the PCB washing wastewater directly enters an alkali distribution tank of a wastewater station for recycling, so that the consumption of new water and the addition of flake caustic soda are saved.
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| CN112980049A (en) * | 2021-03-24 | 2021-06-18 | 重庆先为纤行智能科技有限公司 | Hybrid modification method for in-situ copper removal of non-metal powder of printed circuit board and composite material |
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