WO1998012551A1 - Sistema y metodo para medir el potencial zeta de suspensiones de particulas - Google Patents
Sistema y metodo para medir el potencial zeta de suspensiones de particulas Download PDFInfo
- Publication number
- WO1998012551A1 WO1998012551A1 PCT/ES1997/000228 ES9700228W WO9812551A1 WO 1998012551 A1 WO1998012551 A1 WO 1998012551A1 ES 9700228 W ES9700228 W ES 9700228W WO 9812551 A1 WO9812551 A1 WO 9812551A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- porous medium
- particles
- measuring
- zeta potential
- suspensions
- Prior art date
Links
- 239000000725 suspension Substances 0.000 title claims abstract description 48
- 239000002245 particle Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000005259 measurement Methods 0.000 claims abstract description 17
- 230000007246 mechanism Effects 0.000 claims abstract description 15
- 238000012545 processing Methods 0.000 claims abstract description 3
- 239000007787 solid Substances 0.000 claims description 9
- 230000001105 regulatory effect Effects 0.000 claims description 8
- 230000003321 amplification Effects 0.000 claims description 6
- 238000004140 cleaning Methods 0.000 claims description 6
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 6
- 230000015572 biosynthetic process Effects 0.000 claims description 5
- 238000011282 treatment Methods 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 239000000835 fiber Substances 0.000 abstract description 4
- 239000000123 paper Substances 0.000 description 10
- 230000008569 process Effects 0.000 description 6
- 238000012512 characterization method Methods 0.000 description 5
- 238000005189 flocculation Methods 0.000 description 5
- 239000012530 fluid Substances 0.000 description 5
- 239000000654 additive Substances 0.000 description 4
- 239000000084 colloidal system Substances 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 229920001131 Pulp (paper) Polymers 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- -1 fines Substances 0.000 description 3
- 230000016615 flocculation Effects 0.000 description 3
- 239000011111 cardboard Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 239000011087 paperboard Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 239000012470 diluted sample Substances 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 238000005370 electroosmosis Methods 0.000 description 1
- 238000001962 electrophoresis Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000005188 flotation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 238000011545 laboratory measurement Methods 0.000 description 1
- 238000011005 laboratory method Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012764 mineral filler Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 239000012488 sample solution Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0656—Investigating concentration of particle suspensions using electric, e.g. electrostatic methods or magnetic methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/60—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrostatic variables, e.g. electrographic flaw testing
Definitions
- the invention relates to a system for measuring the zeta potential of a particle suspension, as well as a method for measuring the zeta potential of i or particle suspensions that said system uses.
- the paper machine feed is a suspension of charged particles such as cellulosic fibers, fines, mineral fillers and additives, whose preferred interactions determine efficiency and operability of the chemical processes of the wet part of the paper machine.
- the methods of measuring the electric charge of colloidal or suspended systems are based either on the determination of the charge demand or on the determination of the zeta potential (K. Ueno and K. Kina, J. Chem. Ed. 62 (7 ): 627, 1985;
- the traditional methods of determining load demand are those of colloidal titration, which are based on stoichiometric neutralization of surface charges of colloidal or suspended particles.
- the results obtained are not representative of the colloidal interactions that occur in paper pulp suspensions when the medium has a high ionic strength or when the flocculation mechanism is not neutralizing (L. Bley, Paper Technol. April 1992; DT Lee and PA Patton, TAPPI Papermakers Conference Proceedings, p.555, 1993).
- the control of additives is carried out based on the results obtained in the colloidal titration, it is assumed that the optimum dose of additive corresponds to the isoelectric point of the sample.
- the zeta potential can be calculated using theoretical equations, based on electrokinetic data obtained by experimental electrophoresis, electroosmosis, current potential or sedimentation potential techniques, the basis of which has been known for more than forty years, according to highlights in the general reviews of cited electrokinetic methods (SS Dukhin and BV Deryaguin, Electro-kinetic phenomena. In “Surface and Colloid Science” Vol. 7, Ed. John Wiley, New York, 1974; RJ Hunter, " Zeta potential in colloid science. Principles and applications "Academic Press, London 1988; E. Strazdins, Tappi J. 78 (8): 115, 1995).
- the zeta potential is calculated from the current potential that originates between two electrodes located in the wall of a tube, which contains the sample, by alternately displacing a cylinder inside said tube (Jacobasch, HJ , Baubock, G., Schurz, J., Colloid and Polymer Science 263 (3): 24, 1985; R. Gratton and P. Pruszynski, Pulp and Paper Canada 96 (3): 73, 1995).
- the electro-kinetic equipment that is currently used in line for the determination of the surface charge of the particles of a paper pulp suspension is based on the determination of the potential of current generated between two electrodes when a fiber cake is formed on a filter medium , through which the sample solution is flowed.
- this invention provides a system for measuring the zeta potential of suspended particles that overcomes the aforementioned drawbacks.
- the invention provides a system for measuring zeta potential, which can operate in line and with a continuous flow of the particle suspension, and which can be applied to paper pulp suspensions. In this way, the measurement is carried out on a representative sample, not diluted or altered or fractionated by manipulation or transport to a place other than the process point, with a simple and reliable equipment capable of integrating into the factory environment, being susceptible industrial application both in the paper industry and in other industries that work with similar suspensions where necessary or determine the zeta potential.
- a further objective of this invention is a method for measuring the zeta potential of particle suspensions comprising the use of said system.
- the invention comprises a porous means (2) operatively connected to a watertight moving part (3), located in a pipe or conduit (1), which in turn is connected to a turning mechanism (4), which it causes the rotation of said part (3) and, therefore, of the porous medium (2), and which is operatively connected to a regulating device (5).
- a pipe or conduit (1) In the pipe or conduit (1) two electrodes (6) are introduced, located on both sides of the porous medium (2) and connected to an amplification medium (7) and signal processing (8); and a device for measuring the pressure drop between two points (9) of the pipe or conduit (1) located on both sides of the porous medium (2).
- the porous medium (2) comprises a filter, which can be of commercial sintered glass of those commonly referred to with the numbers 1 to 4, depending on the particle distribution and the concentration of the suspension.
- a filter which can be of commercial sintered glass of those commonly referred to with the numbers 1 to 4, depending on the particle distribution and the concentration of the suspension.
- Polymeric filter materials such as polyethylene, polypropylene, polyaramide filter cloths, commonly used in the industry for the filtration of gases or liquids, can also be used. Said means is mounted on the watertight moving part (3).
- the object of the watertight moving part (3) is to support the porous medium (2), while allowing its rotation, being provided with a rod, which by means of a mechanical seal or a bast press prevents the loss of the circulating liquid by driving.
- This rod is mechanically coupled to the turning device.
- the arrangement of this part inside the conduit is such that, when it is located transversely, there is no flow of fluid between this part and the conduction, in this way, when the moving part is located in transverse position the entire flow of liquid that takes place circulates through the porous medium
- the turning mechanism (4) used is an electric servo motor, provided with contacts by means of cams that allow 180 ° turns of the assembly of the watertight moving part (3) with the porous medium (2), when the servo motor is operated by the regulating device (5).
- a pneumatic, hydraulic servomotor or one of the so-called actuators which in turn can be electric, pneumatic or hydraulic, of those commonly used in industry or in laboratories to perform valve rotation. .
- the regulating device (5) sends a signal to the turning mechanism (4), so that the rotation of the moving part occurs.
- the nature of this signal depends on the device used, so that it acts electrically on a servomotor or, indirectly, acts through a soienoid valve, when the turning mechanism (4) is hydraulic or pneumatic.
- the sequence of rotation established by the regulator can be a function of time, or a function of another physical quantity related to the phenomenon being measured. In our case, a sequence has been used either at a time or a sequence determined by the pressure drop or pressure gauge difference, at points (9) of Figure 1 located on either side of the porous medium.
- the two electrodes (6) used to measure the generated electrical signal are commercial platinum electrodes, commonly used in the laboratory for electrochemical measurements. However, metal electrodes of a different nature can be used, without further limitation than those derived from their compatibility with the medium.
- the signal from the electrodes can optionally be measured with an electrometer or use an amplification medium (7), capable of handling low level electrical signals. In our case, a commercial amplifier 5 of high impedance for direct current electrical signals has been used.
- the amplification means (7) is provided with suitable filters to separate the signal from the electrodes from other possible disturbances induced by the presence of electric machines, radio frequency signals, etc.
- the signal obtained from the amplification medium (7) can be measured and recorded directly with a suitable electrometer and a recorder or processed (8) to obtain statistical values. From the direct measurement or the representative statistical value, by means of a numerical calculator incorporated in the processor, values of the zeta potential are obtained from the Helmholtz-5 Smoluchowski equation (Hunter RJ, Zeta potential in colloid scie ⁇ ce. Principles and applications Academic Press, London 1988).
- Figure 1 shows a schematic drawing of a system for measuring the zeta potential of particle suspensions provided by this invention.
- the 5 reference numbers are explained in the sections that make up this specification.
- the preferred embodiment of the invention consists in circulating a paper pulp suspension through a conduit (1) in which the porous medium (2) that is part of the system object of this invention is located such that the dissolution passes through the porous medium while the solids are retained on their surface forming a cake, the thickness of which is possible to control, 5 by controlling the flow rate passing through the porous medium and / or the measurement time. These conditions can be established based on the solids concentration of the suspension being measured.
- the method of measuring the zeta potential of particle suspensions with the system object of this invention comprises: a) placing a turning mechanism (4) that causes the rotation of a watertight moving part (3) that is attached to said porous means (2) said turning mechanism (4) being operatively connected to a regulating device (5);
- the system in its operation under normal conditions measures the potential of current generated between two electrodes, located in the measuring cell, when a cake of solids is formed on a filter medium, located inside a pipe, due to the continuous flow of the suspension.
- the flow of the suspension causes the particles to deposit on the porous medium while the solution passes through said medium.
- the difference in the concentration of particles on either side of the porous medium, as well as the flow of the fluid through the particles accumulated on the porous medium give rise to a modification in the surface distribution of the electric charges that creates a potential difference that, by means of a suitable treatment of this electrical signal, results in a measurement, in voltage or current that, together with other system parameters (temperature, conductivity, viscosity, dielectric constant and load loss), is used to calculate the zeta potential of the suspension from the theoretical equation of Helmholtz-Smoluchowski, cited above.
- the measurement of the current potential is carried out in cycles whose duration can be optimized, depending on the characteristics of the suspensions, so that a stable and representative measurement of the zeta potential is obtained, at regular intervals of time, whose duration is short enough to consider that the measure is virtually continuous. 5
- the porous element is the one that reverses its position at certain intervals , cleaning itself with the solution that it filters, or so the continuous flow of the particle suspension is maintained. This also avoids the use of auxiliary fluids for cleaning the porous medium used by current equipment.
- the values obtained with the system object of the invention can be used for the online control of the coagulation-flocculation processes of particle suspensions that so require.
- the chemical control of the wet part of the paper machine is highlighted in order to optimize the dose of retention and drainage additives. This allows an improvement in both the papermaking process and the quality of the final product.
- the main object of the invention is the measurement of the zeta potential of the aforementioned suspensions, the procedure is equally valid for the characterization of the behavior of any other system of suspended particles, which require the measurement of the zeta potential.
- the characterization of the behavior of wastewater which contains dispersed matter, as well as the control of the addition of reagents in physical-chemical coagulation-flocculation processes in the treatment of these wastewater.
- it can be used in the characterization of surface charges of finely divided pigment, polymer and mineral dispersions, in paint and dispersion preparation processes, mineral concentration treatments such as flotation, and, in general, in those processes in which the characterization of the surface charge of particles or dispersions of solids in conductive liquids are of interest.
- the invention also provides a method for measuring the zeta potential of particle suspensions comprising the use of the system described above.
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- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Paper (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP97940167A EP0869357A1 (en) | 1996-09-20 | 1997-09-18 | System and method for measuring the zeta potential of suspensions of particles |
AU42099/97A AU4209997A (en) | 1996-09-20 | 1997-09-18 | System and method for measuring the zeta potential of suspensions of particles |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ESP9601992 | 1996-09-20 | ||
ES9601992A ES2117578B1 (es) | 1996-09-20 | 1996-09-20 | Sistema para medir el potencial zeta de suspensiones de particulas. |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998012551A1 true WO1998012551A1 (es) | 1998-03-26 |
Family
ID=8296095
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/ES1997/000228 WO1998012551A1 (es) | 1996-09-20 | 1997-09-18 | Sistema y metodo para medir el potencial zeta de suspensiones de particulas |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0869357A1 (es) |
AU (1) | AU4209997A (es) |
ES (1) | ES2117578B1 (es) |
WO (1) | WO1998012551A1 (es) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7056419B2 (en) | 2002-09-30 | 2006-06-06 | American Air Liquide, Inc. | Methods for modifying electrical properties of papermaking compositions using carbon dioxide |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100390768B1 (ko) * | 2001-05-08 | 2003-07-12 | 한국과학기술연구원 | 중공사 멤브레인의 계면동전기 특성치를 정량적으로산출하기 위한 벌크 흐름전위의 측정장치와 측정방법 |
DE102005061639B4 (de) * | 2005-12-22 | 2007-09-27 | BTG Mütek GmbH | Vorrichtung zur Messung eines Strömungspotentials an einer Feststoffe enthaltenden Flüssigkeit |
GB2479394A (en) * | 2010-04-08 | 2011-10-12 | Daoyi Chen | Measurement of isotopes using zeta potential |
NL2006363C2 (en) * | 2011-03-09 | 2012-09-11 | Adviesburo Magendans B V | The determination of an electrical characteristic of a particles containing liquid. |
CN113574074B (zh) | 2018-10-25 | 2023-03-21 | 营养与生物科学美国第四公司 | α-1,3-葡聚糖接枝共聚物 |
JP2024517798A (ja) | 2021-05-04 | 2024-04-23 | ニュートリション・アンド・バイオサイエンシーズ・ユーエスエー・フォー,インコーポレイテッド | 不溶性アルファ-グルカンを含む組成物 |
WO2023183284A1 (en) | 2022-03-21 | 2023-09-28 | Nutrition & Biosciences USA 4, Inc. | Compositions comprising insoluble alpha-glucan |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4535285A (en) * | 1981-11-09 | 1985-08-13 | The Wiggins Teape Group Limited | Apparatus for determining an electrical characteristic of a fibrous dispersion |
CH671504A5 (en) * | 1985-10-17 | 1989-09-15 | Urs Mueller | Self cleaning filter unit for vacuum cleaners - has rotatable filter disc set on axis with operating member |
EP0462703A1 (en) * | 1990-05-21 | 1991-12-27 | Paper Chemistry Laboratory, Inc. | A method and apparatus for measuring an electrical characteristic of a fibrous dispersion |
-
1996
- 1996-09-20 ES ES9601992A patent/ES2117578B1/es not_active Expired - Fee Related
-
1997
- 1997-09-18 WO PCT/ES1997/000228 patent/WO1998012551A1/es not_active Application Discontinuation
- 1997-09-18 EP EP97940167A patent/EP0869357A1/en not_active Withdrawn
- 1997-09-18 AU AU42099/97A patent/AU4209997A/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4535285A (en) * | 1981-11-09 | 1985-08-13 | The Wiggins Teape Group Limited | Apparatus for determining an electrical characteristic of a fibrous dispersion |
CH671504A5 (en) * | 1985-10-17 | 1989-09-15 | Urs Mueller | Self cleaning filter unit for vacuum cleaners - has rotatable filter disc set on axis with operating member |
EP0462703A1 (en) * | 1990-05-21 | 1991-12-27 | Paper Chemistry Laboratory, Inc. | A method and apparatus for measuring an electrical characteristic of a fibrous dispersion |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7056419B2 (en) | 2002-09-30 | 2006-06-06 | American Air Liquide, Inc. | Methods for modifying electrical properties of papermaking compositions using carbon dioxide |
Also Published As
Publication number | Publication date |
---|---|
ES2117578B1 (es) | 1999-04-01 |
EP0869357A1 (en) | 1998-10-07 |
ES2117578A1 (es) | 1998-08-01 |
AU4209997A (en) | 1998-04-14 |
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