EP1853522A1 - Verfahren zur abtrennung suspendierter feststoffe aus wässrigen systemen mit kolloidalen flockungsmitteln - Google Patents
Verfahren zur abtrennung suspendierter feststoffe aus wässrigen systemen mit kolloidalen flockungsmittelnInfo
- Publication number
- EP1853522A1 EP1853522A1 EP06707407A EP06707407A EP1853522A1 EP 1853522 A1 EP1853522 A1 EP 1853522A1 EP 06707407 A EP06707407 A EP 06707407A EP 06707407 A EP06707407 A EP 06707407A EP 1853522 A1 EP1853522 A1 EP 1853522A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cationic
- colloid particles
- flocculants
- charge
- aqueous medium
- 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.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2/00—Processes of polymerisation
- C08F2/12—Polymerisation in non-solvents
- C08F2/16—Aqueous medium
- C08F2/22—Emulsion polymerisation
-
- 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
- C02F1/54—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
- C02F1/56—Macromolecular compounds
-
- 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
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/30—Nature of the water, waste water, sewage or sludge to be treated from the textile industry
-
- 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
- C02F2103/32—Nature of the water, waste water, sewage or sludge to be treated from the food or foodstuff industry, e.g. brewery waste waters
-
- 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
- C02F2103/343—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 the pharmaceutical industry, e.g. containing antibiotics
-
- 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
-
- 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
- Y10S524/00—Synthetic resins or natural rubbers -- part of the class 520 series
- Y10S524/922—Flocculating, clarifying, or fining compositions
Definitions
- the invention relates to a process for the separation of suspended solids from aqueous systems, in which this is mixed with a flocculant of polymeric colloid particles with cationic surface charge and then the flocculated material is separated from the aqueous system.
- inorganic compounds such as iron or aluminum salts are used as flocculants. Under application conditions these usually form large-volume flakes, which include the material to be separated.
- a decisive disadvantage is that the amounts of inorganic salts used are comparatively high and, as a result, large volumes of sludge are formed.
- Most flocculation processes therefore use water-soluble, organic polymers as flocculants. Both naturally occurring and synthetic polymers are used. The natural polymers are predominantly based on starch as the main body and have the disadvantage that these flocculants are usually applicable in relatively large quantities and then only for a limited number of processes.
- Flocculants based on synthetic polymers have the advantage that they can be produced very specifically with regard to chemical structure and molecular parameters for the particular application. This has resulted in a larger number of flocculants being commercially available. That's in usually cationic or anionic polyelectrolytes which vary with regard to the charge density, the molecular weight and the composition. Typical examples of cationic polyelectrolytes are the condensation products of dimethylamine and epichlorohydrin, the poly (diallyldimethyl-ammonium chloride) and the copolymers of acrylamide and quaternary esters or amides of acrylic acid or methacrylic acid. A typical example of an anionic polyelectrolyte are copolymers of acrylamide and acrylic acid.
- the polyelectrolytes which are technically used as flocculants are linear macromolecules, which are molecularly dissolved under conditions of application. These polyelectrolyte flocculants can be used in very different technologies. These include the one-time or sequential addition of the polymers. In addition, anionic and cationic polyelectrolytes can be applied one after the other in a single process. Well proven technologies are now available for most technical separation processes and it is possible to stably manage a number of flocculation processes. This concerns e.g. municipal wastewater treatment as well as production processes such as papermaking.
- particulate complexes of polycations and polyanions which are present as colloids are described as flocculants (H.M. Buchhammer, M. Oelmann, G. Petzold: Melliand Textile Reports 5 (2001) 391-394; G. Petzold, A Nebel, H. -M. Buchhammer, K. Lunkwitz: Colloid Polym, p. 276 (1998) 125-130).
- These colloids can carry both anionic and cationic charges.
- the production conditions of the particulate complexes are used to adjust the charge and, to a limited extent, the size of these particles.
- the disadvantage is the comparatively larger polymer requirement, which has hitherto prevented a technical application.
- the particle density is relatively small, which is also disadvantageous for the application as a flocculant.
- flocculation window the width of the flocculation area (flocculation window) in numerous technically implemented processes, ie the range between the minimum and maximum amount of polyelectrolyte, the addition of which enables optimal separation.
- a widening of the flocculation window would i.a. bring significant benefits: minimization of the influence of interfering factors, such as pH change, change in the ionic strength, change in the solids concentration.
- Typical examples can be found in the slurries of microelectronics and the wastewater from the pharmaceutical, food and textile industries.
- the present invention is based on the underlying object to provide flocculants, which lead to flocculation to wide flocculation windows and continue to solve the hitherto unsolved separation problems in dilute or finely divided suspensions and suspensions with high levels of impurities and with very broad particle size distribution. Likewise, the task is to eliminate the disadvantages of the prior art mentioned.
- a process for separating suspended solids from aqueous media in which the aqueous medium is mixed with a flocculant of a polymeric colloid particle with cationic surface charge and then the flocculated material is separated from the aqueous medium.
- colloid particles are used which are formed by emulsion copolymerization of a hydrophobic vinyl monomer with a cationic vinyl monomer.
- the emulsion copolymerization is preferably carried out in the feed process.
- the preparation can also be done in a batch process.
- colloid particles consisting of styrene and / or its homologs, e.g. 3, 4-vinyltoluene or t-butylstyrene as hydrophobic monomers and N-methacryloyloxyethyl-N, N, N-trimethylammonium chloride (MADAM), N-methacryloyloxyethyl-N, N-dimethyl-N-benzylammonium chloride (MADAMBQ) and / or 4-vinylpyridine (4-VP) are formed as cationic monomers.
- MADAM N-methacryloyloxyethyl-N, N, N-trimethylammonium chloride
- MADAMBQ N-methacryloyloxyethyl-N, N-dimethyl-N-benzylammonium chloride
- 4-vinylpyridine (4-VP) 4-vinylpyridine
- Essential in the flocculant according to the invention is the cationic surface charge, wherein both the cationic surface charge can be bound directly or via a spacer to the particle surface.
- the colloid particles cm preferably have a charge density of 5 .mu.C / 2 to 35 .mu.C / cm 2, and particularly sawn vorzugt of 8 .mu.C / cm 2 to 22 .mu.C / cm 2.
- the size of the colloid particles according to the invention is preferably from 50 to 1000 nm, preferably from 100 to 150 nm.
- the flocculant For the separation process amounts of the flocculant are used, depending on the aqueous medium sufficient. Separation of the suspended solids allows. Preferably, 0.01 to 500 mg / l g of suspended solids are used.
- the ionic strength of the aqueous medium is increased. This can be done in particular by adding inorganic salts or changing the pH of the aqueous medium.
- the process is therefore preferably in a pH range of 1 to 14 and particularly preferably to 9 in a 'pH range. 3
- the invention also provides the use of cationic surface charge polymeric colloid particles for separating suspended solids from aqueous media. This includes all previously described flocculants which are based on the colloid particles according to the invention. As watery
- aqueous MADAMBQ solution ATOCHEM diluted with ultrapure water to 20 ml and filled into an appropriate syringe.
- the contents are pressed into the reactor uniformly over 2.2 h by syringe pump (see Latices No. 1 - No. 5 in Tab.
- the latex is cooled and the nitrogen flow is interrupted.
- the latex is filtered using a fine metal sieve and dialyzed for precleaning in Visking dialysis tubing (SERVA) against deionized water for 3 days.
- SERVA Visking dialysis tubing
- Fine purification is carried out by ultrafiltration in stirred 400 ml cells (Berghof) on nuclear track membranes (Whatman) with 100 nm diameter of the cylinder pores.
- Molar concentration data in moles per liter of water, with 0.196 liters of water:
- Borax I 83 * 10 "3 mol / l, CTAB I, 68 * 10 " 3 mol / l, styrene 0.685 mol / l, V-50 4.52 * 10 ⁇ 2 mol / l, MADAMBQ 1) 9.44 * 10 ⁇ 3 mol / l, 2) l, 88 * 10 ⁇ 2 mol / l, 3) 2,83 * 10 "2 mol / l, 4) 3,76 * 10 ⁇ 2 mol / l, 5) 4 , 72 * 10 '2 mol / 1.
- the latex particles were examined for their size and surface charge.
- the particle size distribution was determined by means of dynamic light scattering (BI-90 or FOQELS / Brookhaven Inc.). The titration of the
- the flocculation was monitored by measuring the optical density (OD) of the aqueous systems to be assessed at 500 nm (OD 500 ) using a Lambda 900 UV / VIS spectrometer (Perkin-Elmer). The flocculation is considered good if the supernatant is clear. Optically clear supernatants are achieved at OD 500 values equal to or less than 0.3.
- a low charge, low solids disperse dye of 80 mg / l was dispersed in water. To 50 ml of this dye dispersion were added, while stirring, different volumes of a catalyst. No. 5 latex, the subsequent stirring time being 15 minutes. After a sedimentation time of 1 hour, samples of the supernatant were taken and the optical density was measured. The supernatant was clear and completely colorless.
- the FIO ckungs Marie was C Par b S toff / Cp o iymer of 20 mg / 1 without re-stabilization in the investigated range up to 200 mg /. 1
- a low charge, low solids disperse dye of 40 mg / l was treated with commercial cationic polyacrylamides according to the procedure of Example 3. It was not possible to achieve a flocculation without remaining strong residual color.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Environmental & Geological Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Water Supply & Treatment (AREA)
- Engineering & Computer Science (AREA)
- Hydrology & Water Resources (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102005009808A DE102005009808B4 (de) | 2005-03-03 | 2005-03-03 | Verfahren zur Abtrennung suspendierter Feststoffe aus wässrigen Systemen mit kolloidalen Flockungsmitteln |
| PCT/EP2006/001977 WO2006092328A1 (de) | 2005-03-03 | 2006-03-03 | Verfahren zur abtrennung suspendierter feststoffe aus wässrigen systemen mit kolloidalen flockungsmitteln |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP1853522A1 true EP1853522A1 (de) | 2007-11-14 |
Family
ID=36146959
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP06707407A Withdrawn EP1853522A1 (de) | 2005-03-03 | 2006-03-03 | Verfahren zur abtrennung suspendierter feststoffe aus wässrigen systemen mit kolloidalen flockungsmitteln |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US7875189B2 (de) |
| EP (1) | EP1853522A1 (de) |
| DE (1) | DE102005009808B4 (de) |
| WO (1) | WO2006092328A1 (de) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8353641B2 (en) | 2008-02-14 | 2013-01-15 | Soane Energy, Llc | Systems and methods for removing finely dispersed particulate matter from a fluid stream |
| US8349188B2 (en) * | 2008-02-14 | 2013-01-08 | Soane Mining, Llc | Systems and methods for removing finely dispersed particulate matter from a fluid stream |
| US8945394B2 (en) | 2009-10-27 | 2015-02-03 | Soane Energy, Llc | System, methods, processes and apparatus for removing finely dispersed particulate matter from a fluid stream |
| CA2876342C (en) | 2012-06-18 | 2017-06-13 | Soane Mining, Llc | Systems and methods for removing finely dispersed particles from mining wastewater |
| LT6229B (lt) * | 2014-03-10 | 2015-10-26 | Kauno technologijos universitetas | Modifikuoto krakmolo flokuliantas ir jo gamybos būdas |
| DE102018100652A1 (de) * | 2018-01-12 | 2019-07-18 | Leibniz-Institut Für Polymerforschung Dresden E.V. | Verfahren zur abwasseraufbereitung |
Family Cites Families (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3739948A (en) * | 1971-09-21 | 1973-06-19 | Kontes Glass Co | Variable-volume predetermined-bulk liquid dispenser |
| US3994806A (en) * | 1972-03-08 | 1976-11-30 | Calgon Corporation | Composition and method for flocculating suspended solids |
| JPS5144343B2 (de) * | 1972-09-16 | 1976-11-27 | ||
| US3956122A (en) * | 1972-12-18 | 1976-05-11 | American Cyanamid Company | Cationic arylamide-styrene copolymers and flocculation of sewage therewith |
| DE3103099C2 (de) | 1981-01-30 | 1987-01-22 | Robert Bosch Gmbh, 7000 Stuttgart | Verfahren zur Erzeugung eines Aperturkorrektursignals |
| DE3130992A1 (de) * | 1981-08-05 | 1983-02-24 | Henkel KGaA, 4000 Düsseldorf | "polymeres flockungsmittel fuer die aufbereitung von industriewaessern, abwasser, trinkwasser und dergleichen" |
| FR2512006B1 (fr) * | 1981-08-27 | 1985-11-29 | Lambert Jean Pierre | Procede pour clarifier des eaux residuaires |
| FR2640956B1 (de) * | 1988-12-28 | 1991-09-13 | Norsolor Sa | |
| US4931191A (en) * | 1989-01-13 | 1990-06-05 | Nalco Chemical Company | Method for separating solids from water using amine containing polymers |
| US5429749A (en) * | 1994-06-01 | 1995-07-04 | Nalco Chemical Company | Polymers for treatment of food processing wastes |
| US5961839A (en) | 1997-02-07 | 1999-10-05 | Simmsgeiger; Patrick A. | Method for clearing ornamental bodies of water |
| US6171505B1 (en) * | 1998-04-03 | 2001-01-09 | Nalco Chemical Company | Higher actives dispersion polymer to aid clarification, dewatering, and retention and drainage |
| FR2781488B1 (fr) | 1998-07-07 | 2001-04-13 | Snf Sa | Nouveaux polymeres acryliques en dispersions essentiellement aqueuses, leur procede de preparation et leurs applications |
| US6454949B1 (en) * | 2000-09-19 | 2002-09-24 | Baffin, Inc. | Highly accelerated process for removing contaminants from liquids |
| GB0108548D0 (en) | 2001-04-05 | 2001-05-23 | Ciba Spec Chem Water Treat Ltd | Process for flocculating suspensions |
| DE10326630A1 (de) | 2003-06-11 | 2005-01-05 | Basf Ag | Verwendung wässriger Dispersionen, enthaltend Ethylencopolymerwachse |
-
2005
- 2005-03-03 DE DE102005009808A patent/DE102005009808B4/de not_active Expired - Fee Related
-
2006
- 2006-03-03 WO PCT/EP2006/001977 patent/WO2006092328A1/de not_active Ceased
- 2006-03-03 US US11/817,601 patent/US7875189B2/en not_active Expired - Fee Related
- 2006-03-03 EP EP06707407A patent/EP1853522A1/de not_active Withdrawn
Non-Patent Citations (1)
| Title |
|---|
| See references of WO2006092328A1 * |
Also Published As
| Publication number | Publication date |
|---|---|
| DE102005009808A1 (de) | 2006-09-07 |
| DE102005009808B4 (de) | 2007-03-22 |
| US7875189B2 (en) | 2011-01-25 |
| US20080314840A1 (en) | 2008-12-25 |
| WO2006092328A1 (de) | 2006-09-08 |
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