CA2197525A1 - Plating waste water treatment and metals recovery method - Google Patents
Plating waste water treatment and metals recovery methodInfo
- Publication number
- CA2197525A1 CA2197525A1 CA002197525A CA2197525A CA2197525A1 CA 2197525 A1 CA2197525 A1 CA 2197525A1 CA 002197525 A CA002197525 A CA 002197525A CA 2197525 A CA2197525 A CA 2197525A CA 2197525 A1 CA2197525 A1 CA 2197525A1
- Authority
- CA
- Canada
- Prior art keywords
- waste water
- filter
- heavy metal
- stream
- metal ions
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000000034 method Methods 0.000 title claims abstract description 59
- 229910052751 metal Inorganic materials 0.000 title abstract description 18
- 239000002184 metal Substances 0.000 title abstract description 18
- 238000007747 plating Methods 0.000 title abstract description 11
- 238000011084 recovery Methods 0.000 title description 19
- 150000002739 metals Chemical class 0.000 title description 4
- 238000004065 wastewater treatment Methods 0.000 title description 2
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 78
- 239000002351 wastewater Substances 0.000 claims abstract description 59
- 238000001728 nano-filtration Methods 0.000 claims abstract description 48
- 150000002500 ions Chemical class 0.000 claims abstract description 44
- 239000012528 membrane Substances 0.000 claims abstract description 31
- 238000000909 electrodialysis Methods 0.000 claims abstract description 24
- 238000001223 reverse osmosis Methods 0.000 claims abstract description 17
- 238000005868 electrolysis reaction Methods 0.000 claims abstract description 13
- 239000004576 sand Substances 0.000 claims abstract description 11
- 239000003925 fat Substances 0.000 claims abstract description 9
- 239000003921 oil Substances 0.000 claims abstract description 8
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000005342 ion exchange Methods 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 27
- 239000002699 waste material Substances 0.000 claims description 15
- 239000007787 solid Substances 0.000 claims description 10
- 239000013618 particulate matter Substances 0.000 claims description 9
- 238000001179 sorption measurement Methods 0.000 claims description 7
- 238000005273 aeration Methods 0.000 claims description 6
- 229910021645 metal ion Inorganic materials 0.000 claims description 6
- 239000002244 precipitate Substances 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 229930195733 hydrocarbon Natural products 0.000 claims description 4
- 239000012855 volatile organic compound Substances 0.000 claims description 4
- 238000004075 wastewater filtration Methods 0.000 claims description 4
- 238000010793 Steam injection (oil industry) Methods 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 150000002430 hydrocarbons Chemical class 0.000 claims description 3
- 235000014593 oils and fats Nutrition 0.000 claims description 3
- 238000002347 injection Methods 0.000 claims description 2
- 239000007924 injection Substances 0.000 claims description 2
- 150000002825 nitriles Chemical class 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims description 2
- 230000001376 precipitating effect Effects 0.000 claims 3
- 238000004062 sedimentation Methods 0.000 claims 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims 1
- 239000008394 flocculating agent Substances 0.000 claims 1
- 150000002894 organic compounds Chemical class 0.000 claims 1
- -1 organo hydrocarbons Chemical class 0.000 claims 1
- 239000002245 particle Substances 0.000 claims 1
- 238000000926 separation method Methods 0.000 claims 1
- 238000001914 filtration Methods 0.000 abstract description 7
- YFONKFDEZLYQDH-OPQQBVKSSA-N N-[(1R,2S)-2,6-dimethyindan-1-yl]-6-[(1R)-1-fluoroethyl]-1,3,5-triazine-2,4-diamine Chemical compound C[C@@H](F)C1=NC(N)=NC(N[C@H]2C3=CC(C)=CC=C3C[C@@H]2C)=N1 YFONKFDEZLYQDH-OPQQBVKSSA-N 0.000 description 7
- 239000010802 sludge Substances 0.000 description 7
- 241000282320 Panthera leo Species 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- 150000004696 coordination complex Chemical class 0.000 description 3
- 239000011368 organic material Substances 0.000 description 3
- 231100000331 toxic Toxicity 0.000 description 3
- 230000002588 toxic effect Effects 0.000 description 3
- 238000000108 ultra-filtration Methods 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000008139 complexing agent Substances 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000009713 electroplating Methods 0.000 description 2
- 238000001471 micro-filtration Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000010970 precious metal Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 241001136792 Alle Species 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 241000736839 Chara Species 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 101100100125 Mus musculus Traip gene Proteins 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 239000002920 hazardous waste Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000011133 lead Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
- B01D61/027—Nanofiltration
- B01D61/0271—Nanofiltration comprising multiple nanofiltration steps
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/58—Multistep processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/14—Ultrafiltration; Microfiltration
- B01D61/145—Ultrafiltration
- B01D61/146—Ultrafiltration comprising multiple ultrafiltration steps
-
- 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
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D21/00—Processes for servicing or operating cells for electrolytic coating
- C25D21/16—Regeneration of process solutions
- C25D21/20—Regeneration of process solutions of rinse-solutions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2317/00—Membrane module arrangements within a plant or an apparatus
- B01D2317/02—Elements in series
- B01D2317/025—Permeate series
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
- B01D61/025—Reverse osmosis; Hyperfiltration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
- B01D61/027—Nanofiltration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/14—Ultrafiltration; Microfiltration
- B01D61/147—Microfiltration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/42—Electrodialysis; Electro-osmosis ; Electro-ultrafiltration; Membrane capacitive deionization
- B01D61/422—Electrodialysis
-
- 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
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
-
- 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
- C02F1/24—Treatment of water, waste water, or sewage by flotation
-
- 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
- C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
-
- 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
-
- 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
- C02F1/442—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by nanofiltration
-
- 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
-
- 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
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
-
- 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
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
- C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
- C02F1/4676—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electroreduction
- C02F1/4678—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electroreduction of metals
-
- 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
- C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
- C02F1/469—Treatment of water, waste water, or sewage by electrochemical methods by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis
-
- 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
- C02F2101/18—Cyanides
-
- 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
- C02F2103/16—Nature of the water, waste water, sewage or sludge to be treated from metallurgical processes, i.e. from the production, refining or treatment of metals, e.g. galvanic wastes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S204/00—Chemistry: electrical and wave energy
- Y10S204/13—Purification and treatment of electroplating baths and plating wastes
Abstract
A process for removing heavy metal ions or cyanide ions from a waste water stream originating in a metal plating plant or a mine comprising the steps of pretreatment in which the waste water stream is first pretreated by removing particulates, fats and oils; filtration by means of a first sand filterto remove suspended particulates down to 50 microns, a second bag filter to remove suspended particulates down to 3.5 microns, a third micro filter to remove particulates down to 0.1 microns in size and a forth ultrafilter to remove particulate down to a molecular weight of 10,000; concentration of the heavy metal ions in the waste water stream by means of a first stage nanofiltration unit and second stage nanofiltration unit or reverse osmosis membrane unit down to a molecular weight of about 200 with nanofiltration and less by reverse osmosis; increase the concentration of heavy metal species in the waste water stream to above 700 ppm;
electrodialysis to further increase the concentration of heavy metal ions in the waste water stream to approximately 6000 ppm; electrolysis to remove heavy metal ions. Alternatively, ion exchange columns can be used to remove the heavy metal ions after the filtration and concentration in the nanofiltration membranes.
electrodialysis to further increase the concentration of heavy metal ions in the waste water stream to approximately 6000 ppm; electrolysis to remove heavy metal ions. Alternatively, ion exchange columns can be used to remove the heavy metal ions after the filtration and concentration in the nanofiltration membranes.
Description
TITLE
PLATING WASTE WATER TREATMENT AND METALS RECOVERY
METHOD
Field of the invention.
The present invention relates to a method for recovering heavy metals from the rinse water waste stream from metal plating i,-.l..Xl. ;r--s. More particularly, the invention relates to a hybrid process for the efficient leco~.y of heavy metals involving micro filtration, adsorption, a combination of nanofiltration and reverse o~mnsix~ electrodialysis, electrolysis and ion e~ n~e.
Back~Dund of the Invention The metal plating industry col-~u~ s enormous alllUUlllS of water for rinsing the plated materials. The co~u~ lion of water can be in the range of from 10 litres per minute up to 1200 litres per minute depe.~ on the size of the process. The rinse water becollles co..~ d during the plating process when the plated object is rinsed upon removal from the plating bath. The co--~ l~l rinse water is toxic as it can contain several heavy metals such as chrome, copper, zinc, lead, nickel, iron and ch~...ir~lx such as cyanide.
Th~,~rol~, it cannot be released to the en~i~o~ nt without further tre~tm~-nt toremove the heavy metal ions and toxic con~oullds.
In coll~elltional waste water ll~ lllr~ heavy metal co--l~-nin~ waste :~ll'ealllS
are treated with a complexing agent such as sodium, m~g~ or calcium hydlo~ide to form a metal complex. The metal complex is then precipi~led out of the waste stream and settles by gravity to the bottom of a holding tank. The waste water in the holding tank is then cl-rifi~d by removing the pl~cipi~e.
The efflll~nt, which is highly AlkAlin~, neutralized by acid dosing. After this process, the waste water stream can still contain up to 10mg per litre of heavy metals which is an ~m~~ceptAble col1ce~ alion for release to the en~ o.. f .. l In order to meet the ellvhf~ .lAl standards for this type of waste water discharge, which are in the range of 1 to 2 mg per litre for sewer discharge and 0.1 to 0.5 mg per litre for open water dischalge, the waste stream must be further treated using a series of ion e~chAn~e columns to remove heavy metal ions. While the final co~rç~ alions of co~ AIll~
released to the ellvholllllenl may be within euvilon~ l gui-lelin~s, such leleases do place ~1rlitiolrAl strain on municipal sewage sy~lellls and will acc~lm~ tç in the ellvi~ol,.ll~..l with dellilllelll~l long term effects on the biosphere. The precipitated sludge contAining the col~ce.ll.dled heavy metal hydroxide is an extremely hazardous waste and must be disposed of using special facilities at great expense to industry.
The cost of buying water for metal plating in~ triPs ranges from $6000.00 to $10,000.00 per year for a process co~ ...in~ 40 litres per minute. T~lefo.~, there is a need to reduce this cost by recycling as much of the process water aspossible.
There are a l-ul~el of known heavy metal recovery ~ ;lllS. For example, United States Patent 4,880,511, entitled "PROCESS AND APPARATUS FOR
RECOVERY OF PRECIOUS METAL COMPOUND" issued to Sugita on November 14, 1989, describes a process and appalalus for recovery of precious metal coln~oullds such as gold. This process utilizes a reverse osmosis mel~ldlle to sep~. ~lç the c~J..I~...;l~z..~ from the waste stream. The co..l;
is fur~er cOllc~ a~d using an electrodialysis process employing anion-e~h~nge columns and cation~ch~n~e colllmnc. The use of a reverse osmosis membrane means that waste stream Opclalillg at higher p.es~ s (typically in the range of 250 psi to 400 psi) and flow rates must be kept high to create ~ t 97525 turbulence otherwise the n,~ll,b~ es will quickly foul. Th~,erole, this process is not well suited to industrial plating industries due to a greater ten-1enr-y towards "lm~ e fouling because of higher pl~,S and i~ ,ased power input. The waste stream is preferably processed at low plei~uleS to reduce energy input and high velocity to reduce lll~ll,bla~e fouling. United States Patent 4,678,584 entitled "METHOD OF REMOVING HEAVY METAL
FROM WASTEWATER STREAMS" issued to Elfine on July 7, 1989, teaches a method for ll.,dlillg heavy metal-co~ wa~l~wdt~ lleall s using sodium trithiocall,onal~ as a complexing agent and then plecipi~~ g the heavy metal complex out of the waste water. The resllltin~ concentrated heavy metal sludge is further processed using ~ dard m~t~lhlrgical techniques to remove the metals in eco~-....ic~lly useful forms. This method still results in a heavy metal sludge which requires further processing and disposal and lll~lefole added o~ e*,.,lls~s.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the problems and disadvantagesassociated with the known sy~lellls for heavy metal co~ ..,in~le~ rinse water ",~-,l by providing a method which eli---;-~es the need to CO1L~U111C large ~ml)unt~ of precipitate and reliance upon e~l.c ~~ive ion~r~nge columns to finish the pllrifir~ti~n process; has a ~ignifir~ntly i~ ved heavy metal ion recovery efficiency; and facilitates the recovery of process water for reuse.
In one embodiment of the present invention there is provided a method for recov~;.ing heavy metals from a waste water stream co---~-isi-.g the steps of:
waste water prell~al ~ ll to remove solids and suspended oils and fats from the waste water; waste water filtration to filter suspended particulate matter from the waste water; waste water adsorption to remove volatile organic collllx ulldsand hydrocarbons from the waste water; heavy metal col~cenlialion to illc~ase 2 t 97525 .~ .
the conce,lL,alion of heavy metal ions in the waste stream; and, heavy metal removal to remove the heavy metal ions from the waste stream.
In another embodiment of the present invention the waste water plelleO~
co",~,ises the steps of storing a large volume of waste water co..l;~ with heavy metal ions in a se~ l ion/aeration tank; sepâlalillg sll~pen~ed fats and oils from the waste water by steam injection means; removing the floating oils, fats and solids from the surface of the waste water by a surface s~ ;.. ing means; injectin~ colll~ressed air or oxygen into the waster water storage tank by injection means in order to oxidize any organic col~oullds suspended in the waste water; ~lecipilati,lg any s~lspen-1ed solids from the waste water by adding a p,~ipilalillg agent; coll~ctin~ by gravity the p,cci~ led m~tPri~l at the bottom of the said tank; and, removing the pleci~i~ted material from the bottom of the said tank by removal means; and, further proces~ing the i~te material for disposal using processi~ means.
In yet a~ ,er embodiment of the present invention the waste water filtration phase co"~lises the steps of passing said plehedt~,d waste water from said se 1;".. ~ lion/aeration tank to a sand filter; passhlg the effluent from said sand filter to bag filter; passing the effluent from said bag filter to a micro filter;
passing the effluent from said micro filter to an ultrafilter.
In still another embodiment of the present invention, said adsorption comprises passing the effluent from the said micro filter through an adsorber to remove volatile organic co~ ollllds and volatile organic h~oca,~ons.
In another embodiment of the present invention the heavy metal concentration coll,~lises passillg the pre-treated, filtered and adsorbed waste water stream through a first and second filter to collce"llale the heavy metal conce"llalion in the waste water stream; passing said col~cell~aled waste water stream from the filter means to an electrodialysis device for further col~ce--lldLion of heavy metal ions. The first and second filters can be nanofiltration membranes or a co.~i~lion of nanofiltration membranes and reverse osmosi~ n~e...l)ldl es ~lepe.~ p on the re4u-~l-.cr ~ of the system.
In still a further embodiment of the invention, heavy metal removal is accomplished by electrolysis. ~ ively, heavy metal removal can be accomplished by a plurality of ion eYrh~n~e columns.
In yet anolllc~ embodiment of the invention there is a mrtho-l for sepalaLillg and collcellLIdlillg cyanide or cyanide complexes using nanofiltration membranes wl-~.~y the collcel~llated cyanide can be easily oxi~li7~d in the final stage and totally removed from the final treated water stream.
BRIEF DESCRIPTION OF THE DRAVVINGS
The present invention will be further understood from the following description with ~erere.lces to the dlawing in which:
~igure l illustrates a sch~ .lir. of one embodiment of the appa.alus and processof present invention.
DETAILED DESCRIPTION
The process of the present invention uses a pl~ phase, a concentration phase and an ion removal phase.
PRETREATMENT PHASE
The ~rer~"l.,d embodiment of the present invention involves an e~-sive pl~tre~ ll phase in order to remove partir~ tes which could llltim~tely foul the nanofiltration ~ lllblal~s and reverse osmosis membranes. This allows for illcl~ascd life of the membranes and a more reliable process. ~ nt also removes organic colll~oullds and volatile organic compounds and hydrocarbons.
Course solid, oi} and fat removal Rer~ l.ing to Figure l, in the pre~ .l phase, the rinse water waste stream (l) follows the direction of the arrows as shown. Raw waste water (l) is fed to a se~ lionlaeration unit (2) where flo~qtin~ s-1b~ es such as solids, oil and fat are removed by QL ;","~ . If the raw waste water (l) in tank (2) colllains a large amount of s11~pçn-1ed oils and fats, a small qml~11nt of steam can be added to the tank (2) by steam injection inlet (5) which will facilitate the sepaldtion and floatqtion of the oil and fat s~1b~ es. This waste is removed from the top of the sed;...~ lion tank (2) through outlet (3) for further collvt;llLional ll..,l...~-.l and disposal. The waste water stream (l) may also contain a high biological oxygen dem-qn~l due to co.. ~ n by organic material. To oxidize this organic material, compl. ssed air is forced into the settl~m~-nt/aeration tank (2) by way of colnplessed air inlet (5). A suitable coagulant/flocc~11qrlt agent is then added through inlet (4) to precipitate the organic material and s1~QpçTl~led solids to the bottom of the tank (2). Floc andsed;.. ~1 sludge settle to the bottom of tank (2) and are removed from the bottom of tank (2) by way of outlet (6). The sludge is then l-~u~r~ d to an evaporator (lO) where the le..ui,~ water is removed. The dried sludge is then disposed of in a col.~e~.lion~
Ba~.~h Phase The cl-q-rifi~d effln~-nt from the settl~m~nt/aeration tank (2) is then ~ Ç~ d by way of outlet (7) to a m111tim~diq graded sand filter (8). This filter will remove fine ~.~spel~ded solids down to 50 microns. The sand filter (8) is back washed by way of inlet (9). The backwash dischar~e is removed from the sand filter (8) by way of outlet (11) and is Il~Ç."l~d to evaporator (10) for furtherdrying and the dried sludge is disposed of in a collvclllional llrdm~.. The backwashed effluent is llal~r~led from the backwash filter (8) by way of outlet (12)to bag filter (14) by way of inlet (13).
Bag Filt~.;n~
Bag filter (14) contains a series of filtration stages. The first stage of bag filter (14) will remove partir~ tes larger than 35 microns. The second stage of bag filter (14) will remove partir~ tes larger than 15 ll~iClOllS. The third stage of bag filter (14) will remove parti~ tes larger than 3.5 ll~icrolls. Bag filter (14) is periodically flushed by way of water inlet (15). The flushed particulate matter is lla~r."l.,d to evaporator (10) by way of outlet (16). The flushed particulate is further dried and tli~posed of in a coll~elllional manner.
Micro filtration From bag filter (14), the effll~ent is llal~ç~ d by way of outlet (17) to micro filter (18) capable of filtering to 0.2 micron or 0.1 micron. The micro filter (18) can be a one or two stage cartridge type filter or, ~ lively, a back flushed membrane filter. The filter (18) is cleansed by way of back flush inlet (19) and backwdsh from micro filter (18) is llal~L,l.,d to evaporator (20) by way of outlet (21) for further drying and disposal by conventional means. If the process flow is less than 100 litres per minute, then a cartridge filter is suitable. However, for process flows greater than 100 litres per minute and CO.";.i~ p a large load of suspended parti~ tes, a back flushed membldlle filter unit is prer~ ,lcd.
Adsorption If the effluent COllktil~S a large collcenll~lioll of volatile organic compounds(VOCs) or volatile organic hydroc&llJolls (VOHs) the plocess will include an adsorption unit (23) located bclween micro filter (18) and ultrafilter (25). The 21 q7525 ,~,_ adsorber is generally an activated carbon filter.
Ultrafiltration The erlluent exits adsorber (23) by way of outlet (24) and is llal~Çell~,d to ultrafilter (25). Ultrafilter (25) will filter out partir~ tçs having molecular weights greater than 10,000. This filtering will il~c~edse the longevily of the nanofilters (28) and reverse o~mosi~ membranes (41). Without ultrafiltration, there is an illcl~,ased risk that the nanofiltration membranes (28) and/or reverse osmosis membranes (41) will foul during use. Ultrafilter (25) is periodically flushed clean by way of ba~wash inlet (26) . The bac~wash from the 1 0 ultrafilter (25) is tlal~Ç~,led by way of outlet (27) to the evapolatol (20) or eva~o,alion (10) for further drying and collv~ on~l disposal. However, for water having less ten~-nry to foul from biological or ch~mir~l foulants the ultrafiltration stage may be el;--~
CONCENTRATION PHASE
1 5 The collce.lllalion phase comprises a first stage of nanofiltration and a second stage of nanofiltration or reverse osmosis followed by electrodialysis.
Col~cellllalion of the heavy metal ion co"l;....i~ will greatly improve the heavy metal ion co..l~ ..l removal effficiency of the electrolysis device (32).
Nanofiltration The prefiltered effluent stream (70) is Ll~r~.~d to nanofiltration unit (28) which has a molecular weight cut off belweell 180 and 300 depelldillg on the type and surface charge chara~teri~tirs of the nanofiltration ~ lalle used. In operation, nanofiltration unit (28) will filter out metal ions and metal complexes with an effiri~n~-y of 70% to 97% depf n~ g upon such operation parameters as eml-~nt stream pH, op~,~almg ples~e, type and ionic charge of the heavy metal co..~ l, ope.dtillg l~ e.~luic of the waste water stream and the co~-re~.l.alion of the heavy metal co~ ..l in the er~lucnt stream. Where the feed col~ce,llldtion of heavy metal co..l~.l.in~ is in the range of 3 ppm to 300ppm, water recovery from nanofilter (28) will be in the range of 90% to 99.5%. However a recovery of 99.5% or higher can be achieved where the feed collcc~ alion of heavy metal ions ranges bclwcell 3 ppm to 30 ppm.
Example F.mllent (70) contains a heavy metal concentration of 30 ppm. The average rejection characteristic of nanofiltration mc,l,~lalle (28) is 85%. The nanofiltration unit is ope~alcd to achieve a water recovery rate of 98%. The 1 0 resllltin~ nanofiltration yields a pçrm~te stream (29) and a concentrate stream (30). The pc. ..~ e stream (29) will contain 98% of the water and a heavy metal collce.ll~dlion of about 4.6 ppm. The co"cenlldle stream (30) will containabout 2% of the water but about 1275 ppm of heavy metal.
Tank (50) holds a membrane clç~ning solution in the form of either an weak 1 5 solution of organic acid or an anion dete.gc~l solution normally 1 % to 5 %
collcecl~ lion by volume. The clP~nin~ of the lllclll~r~es is done when the process is stopped and the nanofiltration lllenlbldlles and reverse osmosi~
cl,l~ldl~es are isolated from the process by suitable valving means. Cleaning solution from tank (50) is fed into nanofiltration lllem~ldlle (28) as well as reverse osml)si~ ,mbl~llc (41) by way of recirclll~tin~ lines (51) and (52).
The solution then exits the nanofiltration membrane by way of line (53) and the reverse o~mosi~ eclllblalle by line (54). Line (53) and (54) are conn~cted to recirc~ tion line (55) and the c!e~nin~ solution is l~l.. ~-d to tank (50). After several cl~ni~ cycles the cont~nt~ of tank (50) is changed.
The more toxic varieties of heavy metal such as chrome, have ~l~lulol~
dischalge limits far less than 2 ppm. Th.,.cÇo~, pr IIIF~f' stream (40) will have to meet these discharge re(lu~e.llcnls. To accomrlish this, second stage nanofiltration unit (41) will be required. ~ pA~ stream (40) can be lla~r~ ned to second nanofiltration membrane (41) or ~ .. l .l ively to second stage reverse o.~mo~ ,.,m~lalle (41) if dischalge le4uil~ m~nls ~dl,alll a much lower discharge limit, as in the case of chrome.
Example ~.",f~te stream (40) exiting from nanofiltrationunit (28) has a heavy metal ion col~c~dtion of 5 ppm. It will be fed to the second nanofiltration unit (41) whose filtration "mesh" will be "tighter~, that is with a molecular weight cut off b~l~.,en 100 and 180. ~ 'ively, a low yl~,s~ reverse osmosis 1 0 lllc;l~ldl~ rated at 98% salt rejection could be used to achieve signifir~ntly superior filtration rèsults for those applications when zero discharge is t~ly.
Example Using a second nanofiltration unit (41), with 85 % metal rejection and 99%
1 5 water recovery in a recirculation mode, the collcenllation of heavy metal ions in the effluent stream (42), comprising 1 % of the volume of intake stream (40) would be in the range of 425 ppm. This stream is recirculated back to the nanofiltration unit (28) by way of inlet (70). The pPrm~te stream (43) colllylisillg 99% of the volume of intake stream (40) would have a heavy metal ion cQnr~ dlion of 0.76 ppm and can be recycled back to the metal plating process.
Example Using reverse osmosis membranes (41) having a 98.5% metal rejection and Oy.,~a~ g the unit at 99% water recovery in a recirc~ ting mode, the heavy metal co~lcenllàlion in the pe- IllP~l~ stream (43) would be in the range of 0.08 ppm. This water stream can then be directly recycled into the metal plating pr~cess. The heavy metal ion concentration in the collcelllldte stream (42) would be in the range of 492.5 ppm and recirculated back to nanofiltration unit (28).
Ion Exchange Columns As an Altçrn~tive to using electrodialysis conce~ a1ion and electrolytic metal removal, the conr~ . al~ stream (30) from the nanofiltration/lc~ e osmosis units (28 & 41) can be sent to an chPl~tin~ metal ion çxehAn~e column (60) by way of feed line (61). Alllicil,dted effluent (63) heavy metal ion collcellllations would be in the range of 0.5 ppm to 2.0 ppm.
Electrodialysis Concentration If the collcellllal~ stream (30) from nanofiltration lll~l~,alle (28) is high enough, that is in excess of 2000 ppm then the stream can be passed directly to the electrolysis unit. However, where this is not the case, the stream must be further concentrated. This can be done by passing the stream through a direct current electrodialysis device (31) which will further collcellllate the heavy metal ions and ~ .erOI~e reduce the e1P.ctrir~l leS;~lAl~r~P~ across the electrolysis device (32). The collcelll~ale stream (30) is lld~Ç~ d to the electrodialysis unit (31) by way of inlet (33). The metal ions are sep~.AIed from the stream by passing through a series of specially desi~n-P-d stacks of ion e~rr.h~n~e .llblalles. The resllltin~ dilute stream (34) collll)lises be~weell 70% and 95%
of the water elllelillg the electrodialysis device depe~ upon the initial collcelll,alioll of heavy metal ions in the stream (30) from the nanofiltration unit (28). The diluate stream (34) contains a heavy metal collcelllldlion of between 300 ppm and 600 ppm and is fed back to the electrodialysis unit (31) by way of return line (35) for further collcellllalion. Electrodialysis prior to electrolysis will reduce the amount of energy required to recovery the heavy metal ions and improves the overall efficiency of heavy metal ple " 2197525 . ~
The collcellLrdlion of heavy metal ions in effll1ent stream (30) from nanofiltration unit (28) is 1275 ppm. This concenlldle enters the electrodialysis unit (31) oplldling at a water recovery efficiency of 85%. 85% of the unit intake (30) will exit as dilute (34) cont~ining appro~ ly 400 ppm of heavy metal ions. The ~ p 15 % of flow will be co-lcellL~al~ (36) having a heavy metal collcellllalion of 6233 ppm of metal ions. This concellllate stream is then ll~Ç.,ll~d to the electrolytic metal recovery unit (32). Similarly, if the electrodialysis unit (31) is Opl~alillg to obtain a metal ion col~cellllalion of 500 ppm in dilute stream (34) the res~lltin~ col~cellllal~ stream (36) l-al~,Ç~ll.,d to 1 0 the electrolytic unit (32) will have a heavy metal ion collce''l'alion of 5666 ppm. If the effir~ nr-y of the electrodialysis unit (31) is set to 90% water recovery for an intake stream (30) collcellllalion of 1275 ppm, the concentrate stream (36) will have a heavy metal collcelllldlion of 8250 ppm. The electrolytic recovery unit (32) will operate more effiriently with higher 1 5 collcelllla~ stream (36) heavy metal ion col~cellLIalions.
If the collcellllalion of heavy metal ions in the co~celllldte exiting the nanofiltration unit (28) is sllmri~ntly high, the electrodialysis unit is not nrceSc~ry and may be omitted from the process. Col~cenll~dte could then be llàl~r~ ~d dile~lly from the nanofiltration unit (28) to the electrolysis unit (32) for heavy metal ion removal.
METAL REMOVAL PHASE
Electrolysis Collcelllldted effluent stream (36) leaving electrodialysis unit (31) is Llal~r. ~led to electrolytic unit (32) for electrolytic metal leco~."y which is a well known process.
The metal recovery process herein described is best suited for a waste water plOCCSS stream of b~lweell 25,000 litres per day and 1,000,000 litres per day.
, 21 97525 For smaller electroplating operations where the anticipated waste water stream is be~ween 6000 litres per day and 25,000 litres per day, waste water stream (34) exiting from electrodialysis unit (31) can be lla~r~ d to evaporator (37) by way of ~ r~ line (39) for metals recovery rather than rely upon electrolysis (32).
For very small electroplating operations where the alltiCi~dled waste water stream is between 5000 litres per day and 10,000 litres per day, collcenl,ate stream (30) from nanofiltration unit (28) can be fed di~;lly to the evaporator (37) by way of ~ ~r~,r line (38) rather than rely upon electrodialysis unit (31)1 0 and electrolysis (32).
Nu ll~lous mo~1ifir~tions, variations and adaptations may be made to the particular embo~li...~-~.l~ of the invention described above without depalling from the scope of the invention, which are defined in the claims.
PLATING WASTE WATER TREATMENT AND METALS RECOVERY
METHOD
Field of the invention.
The present invention relates to a method for recovering heavy metals from the rinse water waste stream from metal plating i,-.l..Xl. ;r--s. More particularly, the invention relates to a hybrid process for the efficient leco~.y of heavy metals involving micro filtration, adsorption, a combination of nanofiltration and reverse o~mnsix~ electrodialysis, electrolysis and ion e~ n~e.
Back~Dund of the Invention The metal plating industry col-~u~ s enormous alllUUlllS of water for rinsing the plated materials. The co~u~ lion of water can be in the range of from 10 litres per minute up to 1200 litres per minute depe.~ on the size of the process. The rinse water becollles co..~ d during the plating process when the plated object is rinsed upon removal from the plating bath. The co--~ l~l rinse water is toxic as it can contain several heavy metals such as chrome, copper, zinc, lead, nickel, iron and ch~...ir~lx such as cyanide.
Th~,~rol~, it cannot be released to the en~i~o~ nt without further tre~tm~-nt toremove the heavy metal ions and toxic con~oullds.
In coll~elltional waste water ll~ lllr~ heavy metal co--l~-nin~ waste :~ll'ealllS
are treated with a complexing agent such as sodium, m~g~ or calcium hydlo~ide to form a metal complex. The metal complex is then precipi~led out of the waste stream and settles by gravity to the bottom of a holding tank. The waste water in the holding tank is then cl-rifi~d by removing the pl~cipi~e.
The efflll~nt, which is highly AlkAlin~, neutralized by acid dosing. After this process, the waste water stream can still contain up to 10mg per litre of heavy metals which is an ~m~~ceptAble col1ce~ alion for release to the en~ o.. f .. l In order to meet the ellvhf~ .lAl standards for this type of waste water discharge, which are in the range of 1 to 2 mg per litre for sewer discharge and 0.1 to 0.5 mg per litre for open water dischalge, the waste stream must be further treated using a series of ion e~chAn~e columns to remove heavy metal ions. While the final co~rç~ alions of co~ AIll~
released to the ellvholllllenl may be within euvilon~ l gui-lelin~s, such leleases do place ~1rlitiolrAl strain on municipal sewage sy~lellls and will acc~lm~ tç in the ellvi~ol,.ll~..l with dellilllelll~l long term effects on the biosphere. The precipitated sludge contAining the col~ce.ll.dled heavy metal hydroxide is an extremely hazardous waste and must be disposed of using special facilities at great expense to industry.
The cost of buying water for metal plating in~ triPs ranges from $6000.00 to $10,000.00 per year for a process co~ ...in~ 40 litres per minute. T~lefo.~, there is a need to reduce this cost by recycling as much of the process water aspossible.
There are a l-ul~el of known heavy metal recovery ~ ;lllS. For example, United States Patent 4,880,511, entitled "PROCESS AND APPARATUS FOR
RECOVERY OF PRECIOUS METAL COMPOUND" issued to Sugita on November 14, 1989, describes a process and appalalus for recovery of precious metal coln~oullds such as gold. This process utilizes a reverse osmosis mel~ldlle to sep~. ~lç the c~J..I~...;l~z..~ from the waste stream. The co..l;
is fur~er cOllc~ a~d using an electrodialysis process employing anion-e~h~nge columns and cation~ch~n~e colllmnc. The use of a reverse osmosis membrane means that waste stream Opclalillg at higher p.es~ s (typically in the range of 250 psi to 400 psi) and flow rates must be kept high to create ~ t 97525 turbulence otherwise the n,~ll,b~ es will quickly foul. Th~,erole, this process is not well suited to industrial plating industries due to a greater ten-1enr-y towards "lm~ e fouling because of higher pl~,S and i~ ,ased power input. The waste stream is preferably processed at low plei~uleS to reduce energy input and high velocity to reduce lll~ll,bla~e fouling. United States Patent 4,678,584 entitled "METHOD OF REMOVING HEAVY METAL
FROM WASTEWATER STREAMS" issued to Elfine on July 7, 1989, teaches a method for ll.,dlillg heavy metal-co~ wa~l~wdt~ lleall s using sodium trithiocall,onal~ as a complexing agent and then plecipi~~ g the heavy metal complex out of the waste water. The resllltin~ concentrated heavy metal sludge is further processed using ~ dard m~t~lhlrgical techniques to remove the metals in eco~-....ic~lly useful forms. This method still results in a heavy metal sludge which requires further processing and disposal and lll~lefole added o~ e*,.,lls~s.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the problems and disadvantagesassociated with the known sy~lellls for heavy metal co~ ..,in~le~ rinse water ",~-,l by providing a method which eli---;-~es the need to CO1L~U111C large ~ml)unt~ of precipitate and reliance upon e~l.c ~~ive ion~r~nge columns to finish the pllrifir~ti~n process; has a ~ignifir~ntly i~ ved heavy metal ion recovery efficiency; and facilitates the recovery of process water for reuse.
In one embodiment of the present invention there is provided a method for recov~;.ing heavy metals from a waste water stream co---~-isi-.g the steps of:
waste water prell~al ~ ll to remove solids and suspended oils and fats from the waste water; waste water filtration to filter suspended particulate matter from the waste water; waste water adsorption to remove volatile organic collllx ulldsand hydrocarbons from the waste water; heavy metal col~cenlialion to illc~ase 2 t 97525 .~ .
the conce,lL,alion of heavy metal ions in the waste stream; and, heavy metal removal to remove the heavy metal ions from the waste stream.
In another embodiment of the present invention the waste water plelleO~
co",~,ises the steps of storing a large volume of waste water co..l;~ with heavy metal ions in a se~ l ion/aeration tank; sepâlalillg sll~pen~ed fats and oils from the waste water by steam injection means; removing the floating oils, fats and solids from the surface of the waste water by a surface s~ ;.. ing means; injectin~ colll~ressed air or oxygen into the waster water storage tank by injection means in order to oxidize any organic col~oullds suspended in the waste water; ~lecipilati,lg any s~lspen-1ed solids from the waste water by adding a p,~ipilalillg agent; coll~ctin~ by gravity the p,cci~ led m~tPri~l at the bottom of the said tank; and, removing the pleci~i~ted material from the bottom of the said tank by removal means; and, further proces~ing the i~te material for disposal using processi~ means.
In yet a~ ,er embodiment of the present invention the waste water filtration phase co"~lises the steps of passing said plehedt~,d waste water from said se 1;".. ~ lion/aeration tank to a sand filter; passhlg the effluent from said sand filter to bag filter; passing the effluent from said bag filter to a micro filter;
passing the effluent from said micro filter to an ultrafilter.
In still another embodiment of the present invention, said adsorption comprises passing the effluent from the said micro filter through an adsorber to remove volatile organic co~ ollllds and volatile organic h~oca,~ons.
In another embodiment of the present invention the heavy metal concentration coll,~lises passillg the pre-treated, filtered and adsorbed waste water stream through a first and second filter to collce"llale the heavy metal conce"llalion in the waste water stream; passing said col~cell~aled waste water stream from the filter means to an electrodialysis device for further col~ce--lldLion of heavy metal ions. The first and second filters can be nanofiltration membranes or a co.~i~lion of nanofiltration membranes and reverse osmosi~ n~e...l)ldl es ~lepe.~ p on the re4u-~l-.cr ~ of the system.
In still a further embodiment of the invention, heavy metal removal is accomplished by electrolysis. ~ ively, heavy metal removal can be accomplished by a plurality of ion eYrh~n~e columns.
In yet anolllc~ embodiment of the invention there is a mrtho-l for sepalaLillg and collcellLIdlillg cyanide or cyanide complexes using nanofiltration membranes wl-~.~y the collcel~llated cyanide can be easily oxi~li7~d in the final stage and totally removed from the final treated water stream.
BRIEF DESCRIPTION OF THE DRAVVINGS
The present invention will be further understood from the following description with ~erere.lces to the dlawing in which:
~igure l illustrates a sch~ .lir. of one embodiment of the appa.alus and processof present invention.
DETAILED DESCRIPTION
The process of the present invention uses a pl~ phase, a concentration phase and an ion removal phase.
PRETREATMENT PHASE
The ~rer~"l.,d embodiment of the present invention involves an e~-sive pl~tre~ ll phase in order to remove partir~ tes which could llltim~tely foul the nanofiltration ~ lllblal~s and reverse osmosis membranes. This allows for illcl~ascd life of the membranes and a more reliable process. ~ nt also removes organic colll~oullds and volatile organic compounds and hydrocarbons.
Course solid, oi} and fat removal Rer~ l.ing to Figure l, in the pre~ .l phase, the rinse water waste stream (l) follows the direction of the arrows as shown. Raw waste water (l) is fed to a se~ lionlaeration unit (2) where flo~qtin~ s-1b~ es such as solids, oil and fat are removed by QL ;","~ . If the raw waste water (l) in tank (2) colllains a large amount of s11~pçn-1ed oils and fats, a small qml~11nt of steam can be added to the tank (2) by steam injection inlet (5) which will facilitate the sepaldtion and floatqtion of the oil and fat s~1b~ es. This waste is removed from the top of the sed;...~ lion tank (2) through outlet (3) for further collvt;llLional ll..,l...~-.l and disposal. The waste water stream (l) may also contain a high biological oxygen dem-qn~l due to co.. ~ n by organic material. To oxidize this organic material, compl. ssed air is forced into the settl~m~-nt/aeration tank (2) by way of colnplessed air inlet (5). A suitable coagulant/flocc~11qrlt agent is then added through inlet (4) to precipitate the organic material and s1~QpçTl~led solids to the bottom of the tank (2). Floc andsed;.. ~1 sludge settle to the bottom of tank (2) and are removed from the bottom of tank (2) by way of outlet (6). The sludge is then l-~u~r~ d to an evaporator (lO) where the le..ui,~ water is removed. The dried sludge is then disposed of in a col.~e~.lion~
Ba~.~h Phase The cl-q-rifi~d effln~-nt from the settl~m~nt/aeration tank (2) is then ~ Ç~ d by way of outlet (7) to a m111tim~diq graded sand filter (8). This filter will remove fine ~.~spel~ded solids down to 50 microns. The sand filter (8) is back washed by way of inlet (9). The backwash dischar~e is removed from the sand filter (8) by way of outlet (11) and is Il~Ç."l~d to evaporator (10) for furtherdrying and the dried sludge is disposed of in a collvclllional llrdm~.. The backwashed effluent is llal~r~led from the backwash filter (8) by way of outlet (12)to bag filter (14) by way of inlet (13).
Bag Filt~.;n~
Bag filter (14) contains a series of filtration stages. The first stage of bag filter (14) will remove partir~ tes larger than 35 microns. The second stage of bag filter (14) will remove partir~ tes larger than 15 ll~iClOllS. The third stage of bag filter (14) will remove parti~ tes larger than 3.5 ll~icrolls. Bag filter (14) is periodically flushed by way of water inlet (15). The flushed particulate matter is lla~r."l.,d to evaporator (10) by way of outlet (16). The flushed particulate is further dried and tli~posed of in a coll~elllional manner.
Micro filtration From bag filter (14), the effll~ent is llal~ç~ d by way of outlet (17) to micro filter (18) capable of filtering to 0.2 micron or 0.1 micron. The micro filter (18) can be a one or two stage cartridge type filter or, ~ lively, a back flushed membrane filter. The filter (18) is cleansed by way of back flush inlet (19) and backwdsh from micro filter (18) is llal~L,l.,d to evaporator (20) by way of outlet (21) for further drying and disposal by conventional means. If the process flow is less than 100 litres per minute, then a cartridge filter is suitable. However, for process flows greater than 100 litres per minute and CO.";.i~ p a large load of suspended parti~ tes, a back flushed membldlle filter unit is prer~ ,lcd.
Adsorption If the effluent COllktil~S a large collcenll~lioll of volatile organic compounds(VOCs) or volatile organic hydroc&llJolls (VOHs) the plocess will include an adsorption unit (23) located bclween micro filter (18) and ultrafilter (25). The 21 q7525 ,~,_ adsorber is generally an activated carbon filter.
Ultrafiltration The erlluent exits adsorber (23) by way of outlet (24) and is llal~Çell~,d to ultrafilter (25). Ultrafilter (25) will filter out partir~ tçs having molecular weights greater than 10,000. This filtering will il~c~edse the longevily of the nanofilters (28) and reverse o~mosi~ membranes (41). Without ultrafiltration, there is an illcl~,ased risk that the nanofiltration membranes (28) and/or reverse osmosis membranes (41) will foul during use. Ultrafilter (25) is periodically flushed clean by way of ba~wash inlet (26) . The bac~wash from the 1 0 ultrafilter (25) is tlal~Ç~,led by way of outlet (27) to the evapolatol (20) or eva~o,alion (10) for further drying and collv~ on~l disposal. However, for water having less ten~-nry to foul from biological or ch~mir~l foulants the ultrafiltration stage may be el;--~
CONCENTRATION PHASE
1 5 The collce.lllalion phase comprises a first stage of nanofiltration and a second stage of nanofiltration or reverse osmosis followed by electrodialysis.
Col~cellllalion of the heavy metal ion co"l;....i~ will greatly improve the heavy metal ion co..l~ ..l removal effficiency of the electrolysis device (32).
Nanofiltration The prefiltered effluent stream (70) is Ll~r~.~d to nanofiltration unit (28) which has a molecular weight cut off belweell 180 and 300 depelldillg on the type and surface charge chara~teri~tirs of the nanofiltration ~ lalle used. In operation, nanofiltration unit (28) will filter out metal ions and metal complexes with an effiri~n~-y of 70% to 97% depf n~ g upon such operation parameters as eml-~nt stream pH, op~,~almg ples~e, type and ionic charge of the heavy metal co..~ l, ope.dtillg l~ e.~luic of the waste water stream and the co~-re~.l.alion of the heavy metal co~ ..l in the er~lucnt stream. Where the feed col~ce,llldtion of heavy metal co..l~.l.in~ is in the range of 3 ppm to 300ppm, water recovery from nanofilter (28) will be in the range of 90% to 99.5%. However a recovery of 99.5% or higher can be achieved where the feed collcc~ alion of heavy metal ions ranges bclwcell 3 ppm to 30 ppm.
Example F.mllent (70) contains a heavy metal concentration of 30 ppm. The average rejection characteristic of nanofiltration mc,l,~lalle (28) is 85%. The nanofiltration unit is ope~alcd to achieve a water recovery rate of 98%. The 1 0 resllltin~ nanofiltration yields a pçrm~te stream (29) and a concentrate stream (30). The pc. ..~ e stream (29) will contain 98% of the water and a heavy metal collce.ll~dlion of about 4.6 ppm. The co"cenlldle stream (30) will containabout 2% of the water but about 1275 ppm of heavy metal.
Tank (50) holds a membrane clç~ning solution in the form of either an weak 1 5 solution of organic acid or an anion dete.gc~l solution normally 1 % to 5 %
collcecl~ lion by volume. The clP~nin~ of the lllclll~r~es is done when the process is stopped and the nanofiltration lllenlbldlles and reverse osmosi~
cl,l~ldl~es are isolated from the process by suitable valving means. Cleaning solution from tank (50) is fed into nanofiltration lllem~ldlle (28) as well as reverse osml)si~ ,mbl~llc (41) by way of recirclll~tin~ lines (51) and (52).
The solution then exits the nanofiltration membrane by way of line (53) and the reverse o~mosi~ eclllblalle by line (54). Line (53) and (54) are conn~cted to recirc~ tion line (55) and the c!e~nin~ solution is l~l.. ~-d to tank (50). After several cl~ni~ cycles the cont~nt~ of tank (50) is changed.
The more toxic varieties of heavy metal such as chrome, have ~l~lulol~
dischalge limits far less than 2 ppm. Th.,.cÇo~, pr IIIF~f' stream (40) will have to meet these discharge re(lu~e.llcnls. To accomrlish this, second stage nanofiltration unit (41) will be required. ~ pA~ stream (40) can be lla~r~ ned to second nanofiltration membrane (41) or ~ .. l .l ively to second stage reverse o.~mo~ ,.,m~lalle (41) if dischalge le4uil~ m~nls ~dl,alll a much lower discharge limit, as in the case of chrome.
Example ~.",f~te stream (40) exiting from nanofiltrationunit (28) has a heavy metal ion col~c~dtion of 5 ppm. It will be fed to the second nanofiltration unit (41) whose filtration "mesh" will be "tighter~, that is with a molecular weight cut off b~l~.,en 100 and 180. ~ 'ively, a low yl~,s~ reverse osmosis 1 0 lllc;l~ldl~ rated at 98% salt rejection could be used to achieve signifir~ntly superior filtration rèsults for those applications when zero discharge is t~ly.
Example Using a second nanofiltration unit (41), with 85 % metal rejection and 99%
1 5 water recovery in a recirculation mode, the collcenllation of heavy metal ions in the effluent stream (42), comprising 1 % of the volume of intake stream (40) would be in the range of 425 ppm. This stream is recirculated back to the nanofiltration unit (28) by way of inlet (70). The pPrm~te stream (43) colllylisillg 99% of the volume of intake stream (40) would have a heavy metal ion cQnr~ dlion of 0.76 ppm and can be recycled back to the metal plating process.
Example Using reverse osmosis membranes (41) having a 98.5% metal rejection and Oy.,~a~ g the unit at 99% water recovery in a recirc~ ting mode, the heavy metal co~lcenllàlion in the pe- IllP~l~ stream (43) would be in the range of 0.08 ppm. This water stream can then be directly recycled into the metal plating pr~cess. The heavy metal ion concentration in the collcelllldte stream (42) would be in the range of 492.5 ppm and recirculated back to nanofiltration unit (28).
Ion Exchange Columns As an Altçrn~tive to using electrodialysis conce~ a1ion and electrolytic metal removal, the conr~ . al~ stream (30) from the nanofiltration/lc~ e osmosis units (28 & 41) can be sent to an chPl~tin~ metal ion çxehAn~e column (60) by way of feed line (61). Alllicil,dted effluent (63) heavy metal ion collcellllations would be in the range of 0.5 ppm to 2.0 ppm.
Electrodialysis Concentration If the collcellllal~ stream (30) from nanofiltration lll~l~,alle (28) is high enough, that is in excess of 2000 ppm then the stream can be passed directly to the electrolysis unit. However, where this is not the case, the stream must be further concentrated. This can be done by passing the stream through a direct current electrodialysis device (31) which will further collcellllate the heavy metal ions and ~ .erOI~e reduce the e1P.ctrir~l leS;~lAl~r~P~ across the electrolysis device (32). The collcelll~ale stream (30) is lld~Ç~ d to the electrodialysis unit (31) by way of inlet (33). The metal ions are sep~.AIed from the stream by passing through a series of specially desi~n-P-d stacks of ion e~rr.h~n~e .llblalles. The resllltin~ dilute stream (34) collll)lises be~weell 70% and 95%
of the water elllelillg the electrodialysis device depe~ upon the initial collcelll,alioll of heavy metal ions in the stream (30) from the nanofiltration unit (28). The diluate stream (34) contains a heavy metal collcelllldlion of between 300 ppm and 600 ppm and is fed back to the electrodialysis unit (31) by way of return line (35) for further collcellllalion. Electrodialysis prior to electrolysis will reduce the amount of energy required to recovery the heavy metal ions and improves the overall efficiency of heavy metal ple " 2197525 . ~
The collcellLrdlion of heavy metal ions in effll1ent stream (30) from nanofiltration unit (28) is 1275 ppm. This concenlldle enters the electrodialysis unit (31) oplldling at a water recovery efficiency of 85%. 85% of the unit intake (30) will exit as dilute (34) cont~ining appro~ ly 400 ppm of heavy metal ions. The ~ p 15 % of flow will be co-lcellL~al~ (36) having a heavy metal collcellllalion of 6233 ppm of metal ions. This concellllate stream is then ll~Ç.,ll~d to the electrolytic metal recovery unit (32). Similarly, if the electrodialysis unit (31) is Opl~alillg to obtain a metal ion col~cellllalion of 500 ppm in dilute stream (34) the res~lltin~ col~cellllal~ stream (36) l-al~,Ç~ll.,d to 1 0 the electrolytic unit (32) will have a heavy metal ion collce''l'alion of 5666 ppm. If the effir~ nr-y of the electrodialysis unit (31) is set to 90% water recovery for an intake stream (30) collcellllalion of 1275 ppm, the concentrate stream (36) will have a heavy metal collcelllldlion of 8250 ppm. The electrolytic recovery unit (32) will operate more effiriently with higher 1 5 collcelllla~ stream (36) heavy metal ion col~cellLIalions.
If the collcellllalion of heavy metal ions in the co~celllldte exiting the nanofiltration unit (28) is sllmri~ntly high, the electrodialysis unit is not nrceSc~ry and may be omitted from the process. Col~cenll~dte could then be llàl~r~ ~d dile~lly from the nanofiltration unit (28) to the electrolysis unit (32) for heavy metal ion removal.
METAL REMOVAL PHASE
Electrolysis Collcelllldted effluent stream (36) leaving electrodialysis unit (31) is Llal~r. ~led to electrolytic unit (32) for electrolytic metal leco~."y which is a well known process.
The metal recovery process herein described is best suited for a waste water plOCCSS stream of b~lweell 25,000 litres per day and 1,000,000 litres per day.
, 21 97525 For smaller electroplating operations where the anticipated waste water stream is be~ween 6000 litres per day and 25,000 litres per day, waste water stream (34) exiting from electrodialysis unit (31) can be lla~r~ d to evaporator (37) by way of ~ r~ line (39) for metals recovery rather than rely upon electrolysis (32).
For very small electroplating operations where the alltiCi~dled waste water stream is between 5000 litres per day and 10,000 litres per day, collcenl,ate stream (30) from nanofiltration unit (28) can be fed di~;lly to the evaporator (37) by way of ~ ~r~,r line (38) rather than rely upon electrodialysis unit (31)1 0 and electrolysis (32).
Nu ll~lous mo~1ifir~tions, variations and adaptations may be made to the particular embo~li...~-~.l~ of the invention described above without depalling from the scope of the invention, which are defined in the claims.
Claims (27)
1. A method for recovering heavy metals from a waste water stream comprising the steps of:
waste water pretreatment to remove solids, suspended oils and fats from the waste water;
waste water filtration to filter suspended particulate matter from the waste water;
waste water adsorption to remove volatile organic compounds and hydrocarbons from the waste water;
heavy metal concentration to increase the concentration of heavy metal ions in the waste stream; and, heavy metal removal to remove the heavy metal ions from the waste stream.
waste water pretreatment to remove solids, suspended oils and fats from the waste water;
waste water filtration to filter suspended particulate matter from the waste water;
waste water adsorption to remove volatile organic compounds and hydrocarbons from the waste water;
heavy metal concentration to increase the concentration of heavy metal ions in the waste stream; and, heavy metal removal to remove the heavy metal ions from the waste stream.
2. The method as claimed in claim 1, wherein, said waste water pretreatment comprises the steps of storing a large volume of waste water contaminated with heavy metal ions in a sedimentation/aeration tank; separating suspended fats and oils from the waste water by steam injection means;
removing the floating oils, fats and solids from the surface of the waste water by a surface skimming means; injecting compressed air or ozone into the waste water storage tank by injection means in order to oxidize and improve separation in the waste water; precipitating any suspended solids from the wastewater by adding a precipitating agent; collecting by gravity the precipitated material at the bottom of the said tank; and, removing the precipitated materialfrom the bottom of the said tank by removal means; and, further processing the precipitate material for disposal using processing means.
removing the floating oils, fats and solids from the surface of the waste water by a surface skimming means; injecting compressed air or ozone into the waste water storage tank by injection means in order to oxidize and improve separation in the waste water; precipitating any suspended solids from the wastewater by adding a precipitating agent; collecting by gravity the precipitated material at the bottom of the said tank; and, removing the precipitated materialfrom the bottom of the said tank by removal means; and, further processing the precipitate material for disposal using processing means.
3. The method as claimed in claim 2 wherein the precipitating agent is a flocculating agent with suitable characteristics and properties to precipitate the suspended particulate matter in the waste water and cause it to be collectedin the bottom of the tank.
4. The method as claimed in claim 3 wherein said processing means for said precipitate comprise the steps of transferring the said precipitate collected at the bottom of the said tank to an evaporator means to remove moisture from said precipitate matter and disposing of the concentrated and dried precipitate using conventional disposal means.
5. The method as claimed in claim 4 wherein the said pretreatment phase produces pretreated waste water substantially free of oil, fats and floating matter and having a suspended matter greater than 50 microns in size.
6. The method as claimed in claim 1 wherein said waste water filtration phase comprises the steps of passing said pretreated waste water fromsaid sedimentation/aeration tank to a sand filter; passing the effluent from said sand filter to bag filter; passing the effluent from said bag filter to a micro filter; passing the effluent from said micro filter to an ultrafilter.
7. The method as claimed in claim 6 wherein said sand filter is a multi element sand filter; periodically back washed as necessary to remove particulate matter trapped therein; said back wash effluent further processed in an evaporator to separate out the particulate matter for conventional disposal.
8. The method as claimed in claim 7 wherein said sand filter removes particulates down to 50 microns.
9. The method as claimed in claim 7 wherein said bag filter is a multistage bag filter comprising three stages; the first of said stages removingparticulates down to 35 microns; the second of said stages removing particulates down to 15 microns and the third of said stages removing particulates down to 3.5 microns.
10. The method as claimed in claim 9 wherein said bag filter is periodically back washed; the effluent from said back wash transferred to an evaporator to separate the particulate matter for conventional disposal.
11. The method as claimed in claim 6 wherein said micro filter comprises a multistage cartridge filter removing particulates down to 0.1 microns; said filter periodically back washed to remove trapped particulates andsaid back wash further processed for conventional disposal.
12. The method as claimed in claim 6 wherein said micro filter comprises a back flushed membrane filter removing particles down to 0.1 microns; said filter periodically back washed to remove trapped particulates andthe back wash further processed for conventional disposal.
13. The method as claimed in claim 1 wherein said adsorption comprises passing the effluent from the said micro filter through an activated charcoal filter to remove volatile organo compounds and volatile organo hydrocarbons.
14. The method as claimed in claim 6 where in said ultrafilter is a filter capable of removing particulates with molecular weights between 10,000 and 25,000; said filter periodically back washed to remove trapped particulate matter; said back washed particulate matter transferred to an evaporator for further processing and conventional disposal.
15. The method as claimed in claim 1 wherein said heavy metal concentration comprises passing the pre-treated, filtered and adsorbed waste water stream through a first stage filter and second stage filter to concentratethe waste water stream; passing said concentrated waste water stream from said filters to an electrodialysis device for further concentration of heavy metal ions.
16. The method as claimed in claim 15 wherein the said filter comprises a plurality of first stage nanofiltration membranes connected in series/parallel arrangement and a plurality of second stage nanofiltration membranes connected in series/parallel arrangement; said first stage nanofiltration membranes have a molecular weight cut off of between 180 and 300 and said second stage nanofiltration membranes having a molecular weight cut off of between 100 and 200.
17. The method as claimed in claim 15 wherein the said filter comprises a plurality of first stage nanofiltration membranes connected in series/parallel arrangement and a plurality of second stage low pressure reverseosmosis membranes connected in series/parallel arrangement; said first stage nanofiltration membranes have a molecular weight cut off of between 180 and 300 and said second stage low pressure reverse osmosis membranes having a salt rejection between 90% and 98%.
18. The method as claimed in claim 15 wherein the waste water from the said filter means is passed through said electrodialysis device; said deviceoperating on direct current.
19. The method as claimed in claim 1 wherein said heavy metal removal is accomplished by electrolysis.
20. The method as claimed in claim 1 wherein said heavy metal removal is accomplished by a plurality of chelating ion exchange columns
21. An method for recovering heavy metals from a waste water stream comprising a combination of pretreatment, nanofiltration, reverse osmosis electrodialysis and evaporator systems for separating and concentrating heavy metal ions in a waste water stream and electrolysis for removing them.
22. A method for recovering heavy metals from a waste water stream comprising a combination of nanofiltration, reverse osmosis and chelating metal ion exchangers.
23. A method for concentrating heavy metal ions in a waste stream comprising a combination of nanofiltration membranes, reverse osmosis membranes and electrodialysis.
24. A method of concentrating heavy metal ions in a waste stream comprising a combination of nanofiltration membranes and reverse osmosis membranes.
25. A method of concentrating heavy metal ions in a waste water stream comprising a combination of nanofiltration membranes and electrodialysis.
26. A method of removing heavy metal ions from a waste water stream by a combination of nanofiltration membranes and chelating ion exchange columns.
27. A method for separating and concentrating cyanide or cyanide complexes using nanofiltration which can be easily oxidized in the final stage and total removal in treated water stream.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US1164296P | 1996-02-14 | 1996-02-14 | |
US60/011,642 | 1996-02-14 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2197525A1 true CA2197525A1 (en) | 1997-08-15 |
Family
ID=21751349
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002197525A Abandoned CA2197525A1 (en) | 1996-02-14 | 1997-02-13 | Plating waste water treatment and metals recovery method |
Country Status (2)
Country | Link |
---|---|
US (1) | US6162361A (en) |
CA (1) | CA2197525A1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103951119A (en) * | 2014-04-20 | 2014-07-30 | 厦门世达膜科技有限公司 | Process for treating cyaniding barren liquor by combining membrane separation with two-stage membrane electrodialysis |
CN106191978A (en) * | 2016-07-29 | 2016-12-07 | 河南平高电气股份有限公司 | A kind of electroplate liquid filter method |
CN109761412A (en) * | 2018-12-19 | 2019-05-17 | 中国科学院广州地球化学研究所 | The electrolysis treatment process and device of low content organic pollutant in a kind of high salinity rare-earth wet method smelting wastewater |
CN113860558A (en) * | 2021-10-21 | 2021-12-31 | 杭州美易环境科技有限公司 | Dye vat wastewater resource utilization method |
CN114455754A (en) * | 2020-12-27 | 2022-05-10 | 湖南博隆矿业开发有限公司 | Mineral processing wastewater treatment device |
CN114853194A (en) * | 2022-05-12 | 2022-08-05 | 天津城建大学 | Multi-stage adjustable nanofiltration system and salt separation process application |
Families Citing this family (52)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2341602A (en) * | 1997-06-09 | 2000-03-22 | Hw Process Technologies Inc | Method for separating and isolating precious metals from non precious metals dissolved in solutions |
US6391209B1 (en) * | 1999-08-04 | 2002-05-21 | Mykrolis Corporation | Regeneration of plating baths |
US6596148B1 (en) * | 1999-08-04 | 2003-07-22 | Mykrolis Corporation | Regeneration of plating baths and system therefore |
US6942779B2 (en) * | 2000-05-25 | 2005-09-13 | Mykrolis Corporation | Method and system for regenerating of plating baths |
US6645383B1 (en) * | 2000-08-25 | 2003-11-11 | Usf Consumer & Commercial Watergroup, Inc. | Process and apparatus for blending product liquid from different TFC membranes |
GB2385061A (en) * | 2002-02-06 | 2003-08-13 | Accentus Plc | Process water treatment using electrodialysis |
US6878258B2 (en) * | 2002-02-11 | 2005-04-12 | Applied Materials, Inc. | Apparatus and method for removing contaminants from semiconductor copper electroplating baths |
US20030155243A1 (en) * | 2002-02-21 | 2003-08-21 | Eet Corporation | Multi-path split cell spacer and electrodialysis stack design |
US7186344B2 (en) * | 2002-04-17 | 2007-03-06 | Water Visions International, Inc. | Membrane based fluid treatment systems |
US20030226807A1 (en) * | 2002-05-01 | 2003-12-11 | Jeff Watson | Method and apparatus for treating aqueous process baths and their associated waste streams |
US7144511B2 (en) * | 2002-05-02 | 2006-12-05 | City Of Long Beach | Two stage nanofiltration seawater desalination system |
US6863822B2 (en) * | 2002-10-16 | 2005-03-08 | Anthony Pipes | Method and apparatus for parallel desalting |
US20040118780A1 (en) * | 2002-12-20 | 2004-06-24 | Barnstead/Thermolyne Corporation | Water purification system and method |
US7513972B2 (en) * | 2003-05-22 | 2009-04-07 | Hart Resource Technologies, Inc. | Portable brine evaporator unit, process, and system |
GB0312394D0 (en) * | 2003-05-30 | 2003-07-02 | Weir Westgarth Ltd | Filtration apparatus and method |
US8636919B1 (en) | 2004-03-26 | 2014-01-28 | Kenneth D. Hughes | Reactive solutions |
CN1869289B (en) * | 2005-05-26 | 2011-06-29 | 王俊川 | Zero drainage circulation ultilization process and equipment of electroplate waste water |
CN100413791C (en) * | 2005-05-26 | 2008-08-27 | 王俊川 | Circulation utilization technology and equipment for electroplating waste water separated by integrated membrane |
CN100386475C (en) * | 2005-10-17 | 2008-05-07 | 海宁市海整整流器有限公司 | Water comprehensive utilization technology for cleaning electroplating nickel |
WO2008026079A2 (en) * | 2006-07-21 | 2008-03-06 | Saxonia Bio Tec Gmbh | Method and apparatus related to liquid filtration systems |
AU2007299591A1 (en) * | 2006-09-21 | 2008-03-27 | Metallica Minerals Ltd | Improved process and plant for producing nickel |
DE102006047681A1 (en) | 2006-10-09 | 2008-04-10 | Lk Metallwaren Gmbh | Procedure for the treatment of wastewater of a light metal foundry, comprises pre-cleaning the wastewater, and carrying out a further separation of the wastewater by reverse osmosis in low pollutant permeate and pollutant rich retentate |
US20090107915A1 (en) * | 2007-03-12 | 2009-04-30 | Its Engineered Systems, Inc. | Treatment process and system for wastewater, process waters, and produced waters applications |
US20080277262A1 (en) * | 2007-05-11 | 2008-11-13 | Intevras Technologies, Llc. | System and method for wastewater reduction and freshwater generation |
US8277768B2 (en) | 2008-11-14 | 2012-10-02 | Texas Instruments Incorporated | System and method for production of high purity silicon solids and solids therefrom |
MY145568A (en) | 2009-05-27 | 2012-02-29 | Univ Malaysia Tech | A method for treating wastewater containing heavy metals |
US8409442B2 (en) * | 2009-08-20 | 2013-04-02 | Ng Innovations, Inc. | Water separation method and apparatus |
CN101704594B (en) * | 2009-11-27 | 2011-11-16 | 波鹰(厦门)科技有限公司 | Device and method for purifying printing and dyeing advanced treatment wastewater |
US8936770B2 (en) | 2010-01-22 | 2015-01-20 | Molycorp Minerals, Llc | Hydrometallurgical process and method for recovering metals |
US20140014584A1 (en) * | 2010-04-22 | 2014-01-16 | Steven Wayne Cone | Wastewater purification system and method |
EA201790127A3 (en) * | 2010-05-24 | 2017-09-29 | Ксилеко, Инк. | BIOMASS PROCESSING |
CN102372354A (en) * | 2010-08-20 | 2012-03-14 | 山东国强五金科技股份有限公司 | Taxonomic treatment and circular utilization method of electroplating waste water |
CN102452703A (en) * | 2010-10-27 | 2012-05-16 | 王辉 | Method for recovering resources from gold mine cyanide barren solution |
CN103030237B (en) * | 2012-12-29 | 2014-12-10 | 上海安赐机械设备有限公司 | Treatment device and treatment method for recycling coal slurry sewage |
DE102013214981A1 (en) * | 2013-07-31 | 2015-02-05 | Krones Ag | Process and apparatus for the treatment of valuable materials for mines |
CN103539294B (en) * | 2013-10-08 | 2015-07-29 | 南京源泉环保科技股份有限公司 | Reclaim the method for silver-plated waste water and silver |
CN104773887B (en) * | 2015-04-23 | 2016-08-17 | 南京霖厚环保科技有限公司 | Technique and the device of cathode copper is reclaimed from copper-containing wastewater |
RU2628389C2 (en) | 2015-09-02 | 2017-08-16 | Закрытое Акционерное Общество "Аквафор Продакшн" (Зао "Аквафор Продакшн") | Liquid purification method |
RU2614287C2 (en) | 2015-09-02 | 2017-03-24 | Закрытое Акционерное Общество "Аквафор Продакшн" (Зао "Аквафор Продакшн") | Fluid cleaning system |
US20180354817A1 (en) * | 2015-12-03 | 2018-12-13 | Siemens Energy, Inc. | Processes and systems for zinc waste reduction |
WO2018039174A1 (en) * | 2016-08-22 | 2018-03-01 | Pm Power Group | System and method for recycling metals from industrial waste |
CN107043151A (en) * | 2017-06-07 | 2017-08-15 | 中国工程物理研究院动力部 | One heavy metal species comprehensive wastewater portable processing device |
CN107879457B (en) * | 2017-11-20 | 2020-08-28 | 湖南金裕环保科技有限公司 | Heavy metal ion trapping agent, preparation method and use method thereof |
CZ2018635A3 (en) * | 2018-11-16 | 2020-01-22 | Ústav Chemických Procesů Av Čr, V. V. I. | Process for isolating mercury from a solution and apparatus for the process |
CN110028193B (en) * | 2019-03-20 | 2022-05-06 | 北京万邦达环保技术股份有限公司 | Waste water recycling system |
CN111762909A (en) * | 2020-07-17 | 2020-10-13 | 莱特莱德(北京)环境技术股份有限公司 | Device and method for treating and recycling gold-containing barren solution |
CN112499864A (en) * | 2020-11-26 | 2021-03-16 | 深圳市倍鸣洋科技有限公司 | Treatment method for zero discharge of wastewater |
CN113292194A (en) * | 2021-06-08 | 2021-08-24 | 苏州融和福天宝环保科技有限责任公司 | Method for treating electroplating comprehensive wastewater |
US20230191330A1 (en) * | 2021-12-17 | 2023-06-22 | Saline Water Conversion Corporation | System and Method for Monovalent Ion Purification Using Multi-Pass Nanofiltration With Recirculation |
CN115403206B (en) * | 2022-09-30 | 2024-01-23 | 重庆瑜煌电力设备制造有限公司 | Method and device for color galvanization |
CN115974327A (en) * | 2023-01-06 | 2023-04-18 | 深圳市山水乐环保科技有限公司 | Nickel recovery system and process for nickel plating wastewater |
CN116789323A (en) * | 2023-07-27 | 2023-09-22 | 珠海市江河海水处理科技股份有限公司 | Electroplating copper waste water recycling equipment |
Family Cites Families (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3674669A (en) * | 1970-04-01 | 1972-07-04 | Rai Res Corp | Concentration of electrolyte from dilute washings by electrodialysis in a closed system |
US3637467A (en) * | 1970-05-07 | 1972-01-25 | Osmonics Inc | Metal reclamation process and apparatus |
US3766049A (en) * | 1971-08-26 | 1973-10-16 | Process Res Inc | Recovery of metal from rinse solutions |
US3925202A (en) * | 1974-04-25 | 1975-12-09 | Hydromation Filter Co | Method of and apparatus for filtering water |
JPS51109286A (en) * | 1975-03-22 | 1976-09-28 | Hitachi Ltd | |
US4111772A (en) * | 1975-05-22 | 1978-09-05 | Pitt Metals And Chemicals, Inc. | Process for electrodialytically controlling the alkali metal ions in a metal plating process |
EP0056999A3 (en) * | 1981-01-22 | 1982-09-29 | Sankyo Yuki Kabushiki Kaisha | Method of treatment for separation of oil from oil-containing slurry waste |
US4655928A (en) * | 1983-10-18 | 1987-04-07 | Gnb Incorporated | Membrane processes for metal recovery and pollution control in metal process industries |
US4702838A (en) * | 1984-08-20 | 1987-10-27 | Bend Research, Inc. | Selective and continuous removal of metal-ion contaminants from plating baths |
EP0246070B1 (en) * | 1986-05-16 | 1991-01-16 | Electroplating Engineers of Japan Limited | Process and apparatus for recovery of precious metal compound |
US4885095A (en) * | 1987-04-03 | 1989-12-05 | Water Technologies, Inc. | System for separating solutions |
US4895659A (en) * | 1987-04-30 | 1990-01-23 | Regents Of The University Of Minnesota | Method for metal and cyanide recovery from plating baths and rinse waters |
DE3815271A1 (en) * | 1988-05-05 | 1989-11-16 | Sandoz Ag | METHOD FOR CLEANING INDUSTRIAL SEWAGE |
CA2109436C (en) * | 1991-05-01 | 2002-02-05 | Level Valley Dairy Company | Wastewater treatment system |
US5244580A (en) * | 1992-01-10 | 1993-09-14 | Li Chung Lee | Method of removal and recovery of oil and grease from wastewater |
US5328616A (en) * | 1992-11-20 | 1994-07-12 | Monsanto Company | Methods and apparatus for treating electroless plating baths |
US5277817A (en) * | 1992-11-20 | 1994-01-11 | Monsanto Company | Apparatus and methods for treating electroless plating baths |
US5718828A (en) * | 1996-01-26 | 1998-02-17 | Hydromatix Inc. | Method for minimizing wastewater discharge |
-
1997
- 1997-02-13 CA CA002197525A patent/CA2197525A1/en not_active Abandoned
- 1997-02-14 US US08/799,308 patent/US6162361A/en not_active Expired - Fee Related
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103951119A (en) * | 2014-04-20 | 2014-07-30 | 厦门世达膜科技有限公司 | Process for treating cyaniding barren liquor by combining membrane separation with two-stage membrane electrodialysis |
CN106191978A (en) * | 2016-07-29 | 2016-12-07 | 河南平高电气股份有限公司 | A kind of electroplate liquid filter method |
CN109761412A (en) * | 2018-12-19 | 2019-05-17 | 中国科学院广州地球化学研究所 | The electrolysis treatment process and device of low content organic pollutant in a kind of high salinity rare-earth wet method smelting wastewater |
CN114455754A (en) * | 2020-12-27 | 2022-05-10 | 湖南博隆矿业开发有限公司 | Mineral processing wastewater treatment device |
CN113860558A (en) * | 2021-10-21 | 2021-12-31 | 杭州美易环境科技有限公司 | Dye vat wastewater resource utilization method |
CN114853194A (en) * | 2022-05-12 | 2022-08-05 | 天津城建大学 | Multi-stage adjustable nanofiltration system and salt separation process application |
Also Published As
Publication number | Publication date |
---|---|
US6162361A (en) | 2000-12-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CA2197525A1 (en) | Plating waste water treatment and metals recovery method | |
US5403490A (en) | Process and apparatus for removing solutes from solutions | |
US7144510B2 (en) | Method and apparatus for treatment of a fluid stream | |
JP2001070989A (en) | Method and apparatus for treating organic wastewater containing high concentration of salts | |
NO301636B1 (en) | Procedure for removing dissolved metals from wastewater | |
Zuo et al. | Characteristics and application of multiple membrane process in plating wastewater reutilization | |
Huang et al. | Separation of heavy metals from industrial waste streams by membrane separation technology | |
CN213012286U (en) | Membrane filtration and heavy metal-containing wastewater purification system | |
Janson et al. | Treatment of heavy metals in wastewaters. What wastewater‐treatment method is most cost‐effective for electroplating and finishing operations? Here are the alternatives | |
CN205662404U (en) | Zero release water treatment facilities | |
CN102311180B (en) | Method for removing and recovering copper and zinc in wastewater of copper-zinc catalysts | |
CN110183018A (en) | A kind of shunt electroplating sewerage Zero discharge treatment method | |
Trebouet et al. | Effect of operating conditions on the nanofiltration of landfill leachates: pilot-scale studies | |
Smith et al. | Polymer Filtration: A new technology for selective metals recovery | |
CN201610402U (en) | Recycling and deep treatment device for electronic electroplating wastewater | |
Srisuwan et al. | Removal of heavy metals from electroplating wastewater by membrane | |
EP1242313B1 (en) | Waste water treatment system | |
CN107098526A (en) | The film concentrator and handling process of strong brine zero-emission sub-prime crystallization | |
CN210030227U (en) | Concentration treatment device for chemical nickel plating rinsing wastewater | |
CN111875094B (en) | Comprehensive treatment process for beryllium-containing wastewater | |
Slater et al. | Removal of cadmium from metal processing wastewaters by reverse osmosis | |
CN210313765U (en) | Fluorine-containing high-salinity wastewater recycling system | |
CN109761383B (en) | Recycling and treating method and recycling and treating system for heavy metal wastewater | |
CN213012284U (en) | System for be used for carrying out filtration treatment and jointly removing heavy processing to waste water | |
CN111875095B (en) | Comprehensive treatment system for beryllium-containing wastewater |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
FZDE | Discontinued |