CN102087103A - Ultrafiltration membrane bubble point determinator and ultrafiltration membrane average pore size determination method - Google Patents
Ultrafiltration membrane bubble point determinator and ultrafiltration membrane average pore size determination method Download PDFInfo
- Publication number
- CN102087103A CN102087103A CN 201010579477 CN201010579477A CN102087103A CN 102087103 A CN102087103 A CN 102087103A CN 201010579477 CN201010579477 CN 201010579477 CN 201010579477 A CN201010579477 A CN 201010579477A CN 102087103 A CN102087103 A CN 102087103A
- Authority
- CN
- China
- Prior art keywords
- filtration membrane
- ultra filtration
- average pore
- bubble point
- pore size
- 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.)
- Granted
Links
Images
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention discloses an ultrafiltration membrane bubble point determinator and an ultrafiltration membrane average pore size determination method. The ultrafiltration membrane bubble point determinator comprises an average pore size bubble point pressure determination module used for detecting the air flow of ventilation micropores in an ultrafiltration membrane, and the current air pressure in an air chamber of the ultrafiltration membrane bubble point determinator is judged to be an average pore size bubble point pressure when the air flow reaches a criterion, wherein the criterion is as follows: the air flow is 8-10ml/min. By applying the determinator and the method provided by the invention, the average pore sizes of the ultrafiltration membranes with larger pore sizes can be rapidly and accurately determined.
Description
Technical field
The present invention relates to mensuration, particularly relate to a kind of ultra filtration membrane bubble point analyzer and a kind of ultra filtration membrane average pore size assay method that adopts this ultra filtration membrane bubble point analyzer to realize the structurally associated parameter of ultra filtration membrane.
Background technology
Form sign to perforated membrane comprises structurally associated parameter and infiltration correlation parameter.Structural parameters mainly comprise: aperture (maximum diameter of hole and average pore size), pore diameter distribution, skin thickness and surface porosity factor; Permeability parameters then refers to measure the actual separation parameter of the perforated membrane of definite model to specific solute by the rejection of solute.
Microfiltration membranes is the bigger perforated membrane in aperture, ultra filtration membrane then is the less perforated membrane in aperture, average pore size is a fundamental characteristics parameter of this two classes filter membrane, determining its application or use project, the average pore size of therefore measuring this two classes filter membrane exactly is crucial for filter membrane development and production unit.
At present, the assay method to the average pore size of microfiltration membranes and ultra filtration membrane generally is divided into two kinds: bubble point method and standard particle method.
Being example with the commercially available DJ-5 type bubble point analyzer that gets describes the principle of work of bubble point method.The bubble point method mainly is the aperture of air being measured filter membrane through the required pressure of filter membrane of full of liquid by measuring.In the bubble point analyzer, the upper surface of filter membrane contacts with liquid (for example water) in the bubble chamber, and liquid makes filter membrane wetting, this moment filter membrane equal this liquid abrim of all micropores; The lower surface of this filter membrane then is communicated with air chamber, and when increasing air pressure in the air chamber to certain value gradually, air just can begin to pass the micropore of filter membrane, forms bubble in bubble chamber.At this moment, relation between the micropore size of air pressure and filter membrane is determined by Laplace equation d=4k σ cos θ/p, wherein, d represents the diameter of micropore, and p represents air pressure (differential pressure), and k represents the pass correction factor of filter membrane, σ represents the surface tension coefficient of this liquid, θ represents the contact angle of this liquid and filter membrane, and k, σ and θ are constant for the ultra filtration membrane of the ultra filtration membrane bubble point analyzer of determining and definite model, and the also more or less freely mensuration exactly of the numerical value of σ and θ.
Yet at coefficient k (comprising the pass factor and tortuosity), because its value can be subjected to all multifactor influences such as filter membrane material, processing technology and filter membrane thickness, therefore for domestic each tame filter manufacturer's and filter material manufacturer, even filter membrane that oneself use or own production often also is difficult to measure exactly the coefficient k of this filter membrane.So this just becomes employing bubble point method and measures the maximum diameter of hole of filter membrane and first technological difficulties of average pore size exactly.
In addition, by above-mentioned Laplace equation as can be seen, be inverse relation between micropore size d and the air pressure p, along with the increase of air pressure, micropore place in the aperture maximum can at first begin to form bubble, and each micropore place that reduces gradually in the aperture then also can begin to form successively bubble.Therefore, mensuration to the maximum diameter of hole of filter membrane in the bubble point method realizes than being easier to, in case observe first bubble of emerging, just can be with the p in the air pressure substitution Laplace equation in this moment air chamber, thus calculate the maximum diameter of hole of this tested filter membrane.
Yet the average pore size that calculates filter membrane will have been discussed in two kinds of situation.For microfiltration membranes, its aperture is generally in 0.1～2.0 micron scope, and pore diameter distribution is more concentrated, in the mensuration process of bubble point method, usually after observing first bubble point, a large amount of bubbles will soon occur, the method that therefore general employing segmentation is boosted is measured its pore diameter distribution, and then tries to achieve the average pore size of this microfiltration membranes.In the mensuration practice of reality, when force value rises to the 110%-120% of first continuous air bubbles point pressure value, then the gaseous tension in the current air chamber can be judged to be the average pore size bubble point pressure, by with the p in this average pore size bubble point pressure substitution Laplace equation, just can calculate the average pore size of this tested microfiltration membranes.And for ultra filtration membrane, its aperture is general all less than 0.1 micron, and pore diameter distribution is rendered as normal distribution, be that the ultra filtration membrane total surface is to exist the micropore of a spot of larger aperture and the micropore of a large amount of smaller aperture due, usually after first bubble occurring, increase gradually along with air pressure, number of bubbles only can increase lentamente, therefore, air pressure when should be judged to be the average pore size bubble point pressure actually, just become second technological difficulties that adopts the bubble point method to measure the average pore size of ultra filtration membrane exactly.
In view of the average pore size that adopts the bubble point method to measure ultra filtration membrane exists above-mentioned two technological difficulties, for the less relatively class in aperture in the ultra filtration membrane (micropore size is less than 0.01 micron), general molecular weight cut off or the rejection that adopts " standard particle method " to measure ultra filtration membrane, this method is mainly used in the separating property that characterizes ultra filtration membrane.Because ultra filtration membrane is generally used for the separation of macromolecular substances, concentrated and purification, therefore reflect that with molecular weight cut off the size in ultra filtration membrane aperture is comparatively easily on using.The selection principle of institute's accepted standard particle is: be sphere in solution; The purity height, stable, inexpensive; Concentration is easily analyzed, particularly analysis precision height when low concentration.But, because the employed standard particle thing of each production firm has nothing in common with each other, difference to some extent on solution concentration and working pressure, and different separately regulations is also arranged when determining the rejection percentage value of molecular weight cut off, and therefore the separating property with the ultra filtration membrane of this method sign only has reference value.
Yet for the relatively large ultra filtration membrane in aperture (micropore size is in 0.01～0.1 micrometer range), owing to be difficult to select the standard particle thing of suitable ultrahigh molecular weight, the mensuration of therefore carrying out molecular weight cut off will compare difficulty.
In sum, in the ultra filtration membrane of various models, on the one hand, for the less relatively ultra filtration membrane in aperture, the measurement result of standard particle method only has reference value, for the relatively large ultra filtration membrane in aperture, then is difficult to adopt the standard particle method to be measured; On the other hand, if adopt the bubble point method that the average pore size of ultra filtration membrane is measured,, but exist two above-mentioned technological difficulties though operate fairly simple conveniently.
At present, with the relatively large ultra filtration membrane of microfiltration membranes and aperture is the important new technology that membrane bioreactor (MBR) technology of core component has become wastewater treatment and water resource reuse field in the environmental engineering, it is a kind of novel sewage water treatment method that the high performance membrane separating technology is combined with traditional activated sludge process, can be widely used in municipal wastewater and multiple organic industrial sewage process field.Therefore, the technical barrier that how to solve the average pore size of measuring the relatively large ultra filtration membrane in ultra filtration membrane, especially aperture has exactly become a problem demanding prompt solution.
Summary of the invention
The technical problem to be solved in the present invention is in order to overcome the defective that prior art is difficult to measure exactly the average pore size of the relatively large ultra filtration membrane in aperture, a kind of ultra filtration membrane bubble point analyzer and a kind of ultra filtration membrane average pore size assay method that adopts this ultra filtration membrane bubble point analyzer to realize that can measure the average pore size of the relatively large ultra filtration membrane in aperture rapidly and accurately to be provided.
The present invention solves above-mentioned technical matters by following technical proposals: a kind of ultra filtration membrane bubble point analyzer, it comprises average pore size bubble point pressure mensuration module, be used to survey the airshed of ventilating microhole on the ultra filtration membrane, in case judge just when this airshed reaches a criterion that the current air pressure in the air chamber of this ultra filtration membrane bubble point analyzer is the average pore size bubble point pressure, its characteristics are that this criterion is: this airshed is 8ml/min～10ml/min.
Preferably, the micropore size of described ultra filtration membrane is in 0.01～0.1 micrometer range.
The present invention also provides a kind of ultra filtration membrane average pore size assay method, its characteristics are, it comprises: S1, the high-resolution scanning electron microscope of employing are taken pictures to the microcellular structure on sample ultra filtration membrane surface, and the measurement by the microcellular structure in the comparison film, calculate the average pore size of sample ultra filtration membrane; S2, utilize the described ultra filtration membrane bubble point of claim 1 analyzer to measure the average pore size bubble point pressure of sample ultra filtration membrane; S3, based on Laplace equation d=4k σ cos θ/p, wherein σ and θ are constant for the ultra filtration membrane of the ultra filtration membrane bubble point analyzer of determining and definite model, with the average pore size substitution d of the sample ultra filtration membrane that calculate to obtain among the step S1, with the average pore size bubble point pressure substitution p of the sample ultra filtration membrane measured among the step S2, thereby calculate k; S4, utilize the described ultra filtration membrane bubble point of claim 1 analyzer to measure the average pore size bubble point pressure of actual ultra filtration membrane, wherein actual ultra filtration membrane is identical with sample ultra filtration membrane model; S5, based on Laplace equation d=4k σ cos θ/p, with the k that calculate to obtain among the step S3 as constant, with the average pore size bubble point pressure substitution p of the actual ultra filtration membrane measured among the step S4, thereby calculate the average pore size of actual ultra filtration membrane.
Preferably, the enlargement factor of described scanning electron microscope is 100～650000 times.
Preferably, the micropore size of described ultra filtration membrane is in 0.01～0.1 micrometer range.
Positive progressive effect of the present invention is: applicant of the present invention is the characteristics of normal distribution according to the micropore size of ultra filtration membrane, and based on a large amount of experimental studies, to being used in the existing bubble point analyzer to judge that the criterion that air chamber air pressure when is judged to be the average pore size bubble point pressure improves, criterion after this improvement meets the pore size distribution characteristics specified of ultra filtration membrane more, thereby the average pore size bubble point pressure that makes this ultra filtration membrane bubble point analyzer of the present invention be measured is comparatively accurate, has just solved one of them technological difficulties of being mentioned in the background technology thus; In addition, this ultra filtration membrane bubble point analyzer also is very fast to the mensuration process of the average pore size bubble point pressure of ultra filtration membrane, whole mensuration process consuming time not even above 15 minutes, this compares with the standard particle method of complicated operation, obviously determination efficiency significantly improves, and with utilizing scanning electron microscope ultra filtration membrane is taken pictures, then the manual measurement of wasting time and energy of the micropore size in the comparison film, and the method that finally counts average pore size compares, and determination efficiency then significantly improves especially.This ultra filtration membrane average pore size assay method of the present invention is then adopting this ultra filtration membrane bubble point analyzer to measure on the basis of average pore size bubble point pressure of ultra filtration membrane, also propose a kind of means that coefficient k in the Laplace equation is revised further, just solved another technological difficulties of being mentioned in the background technology thus.In sum, when adopting this ultra filtration membrane bubble point analyzer of the present invention and this ultra filtration membrane average pore size assay method to measure the average pore size of the relatively large ultra filtration membrane in aperture, not only the accuracy of gained measurement result is higher, and whole mensuration process is very fast, and determination efficiency is high.
Description of drawings
Fig. 1 is the process flow diagram of this ultra filtration membrane average pore size assay method of the present invention.
Embodiment
Provide preferred embodiment of the present invention below in conjunction with accompanying drawing, to describe technical scheme of the present invention in detail.
This ultra filtration membrane bubble point analyzer of the present invention and existing bubble point analyzer include an average pore size bubble point pressure similarly and measure module.The principle of work of this average pore size bubble point pressure mensuration module as described in the background art, continuous increase along with the air pressure in the air chamber, this module can be constantly surveyed all total ventilation airsheds that are in the micropore of aeration status (bubbling state) on the tested ultra filtration membrane, and this airshed that will survey acquisition constantly compares with a criterion of presetting, in case this airshed reaches this default criterion, just the current air pressure in judgement air chamber this moment just is the average pore size bubble point pressure at this tested ultra filtration membrane.And unlike the prior art be that in this ultra filtration membrane bubble point analyzer of the present invention, the concrete numerical value of the criterion that this is default is: the numerical value of this airshed is 8ml/min～10ml/min.
This average pore size bubble point pressure measure module can be at an easy rate means by electronic circuitry design and software algorithm programming realize, do not give unnecessary details so its implementation procedure is not done at this.
This ultra filtration membrane bubble point analyzer of the present invention can be adapted to the ultra filtration membrane in various apertures in theory, yet, consider on the one hand when the aperture of ultra filtration membrane relatively hour, air pressure in the air chamber needs to reach very high numerical value, causes certain technical difficulty therefore can for the design and the manufacturing of this ultra filtration membrane bubble point analyzer; On the other hand, for being for the MBR of core component with microfiltration membranes and ultra filtration membrane, along with the progress of its process exploitation, its a large amount of ultra filtration membranes that adopt generally are the ultra filtration membrane with dissymmetrical structure of aperture relatively large (micropore size is in 0.01～0.1 micrometer range).Therefore comprehensive above-mentioned two aspect reasons, this ultra filtration membrane bubble point analyzer of the present invention will be applicable to the ultra filtration membrane of micropore size in 0.01～0.1 micrometer range more.
Below with reference to Fig. 1 this ultra filtration membrane average pore size assay method of the present invention is described, this method may further comprise the steps:
Because measurement result of the present invention is comparatively accurate and finding speed is exceedingly fast, therefore the applicant has been defined as this mensuration the conventional determining mode of the large aperture ultra filtration membrane average pore size of the MBR of this enterprise special use, and classifies it as in the ultra filtration membrane production run quality monitoring content.Following table is the result that this enterprise obtains when utilizing the present invention that the average pore size of the special-purpose ultra filtration membrane of MBR is measured, as can be seen, the reappearance of determination data is still very high, and this has also proved the validity of measurement result once more.
In sum, the present invention can measure the average pore size of the relatively large ultra filtration membrane in ultra filtration membrane, especially aperture rapidly and accurately, and determination efficiency is high.
Though more than described the specific embodiment of the present invention, it will be understood by those of skill in the art that these only illustrate, protection scope of the present invention is limited by appended claims.Those skilled in the art can make numerous variations or modification to these embodiments under the prerequisite that does not deviate from principle of the present invention and essence, but these changes and modification all fall into protection scope of the present invention.
Claims (5)
1. ultra filtration membrane bubble point analyzer, it comprises average pore size bubble point pressure mensuration module, be used to survey the airshed of ventilating microhole on the ultra filtration membrane, in case judge just when this airshed reaches a criterion that the current air pressure in the air chamber of this ultra filtration membrane bubble point analyzer is the average pore size bubble point pressure, it is characterized in that this criterion is: this airshed is 8ml/min～10ml/min.
2. ultra filtration membrane bubble point analyzer as claimed in claim 1 is characterized in that the micropore size of described ultra filtration membrane is in 0.01～0.1 micrometer range.
3. ultra filtration membrane average pore size assay method is characterized in that it comprises:
S1, the high-resolution scanning electron microscope of employing are taken pictures to the microcellular structure on sample ultra filtration membrane surface, and pass through the measurement of the micropore size in the comparison film, calculate the average pore size of sample ultra filtration membrane;
S2, utilize the described ultra filtration membrane bubble point of claim 1 analyzer to measure the average pore size bubble point pressure of sample ultra filtration membrane;
S3, based on Laplace equation d=4k σ cos θ/p, wherein σ and θ are constant for the ultra filtration membrane of the ultra filtration membrane bubble point analyzer of determining and definite model, with the average pore size substitution d of the sample ultra filtration membrane that calculate to obtain among the step S1, with the average pore size bubble point pressure substitution p of the sample ultra filtration membrane measured among the step S2, thereby calculate k;
S4, utilize the described ultra filtration membrane bubble point of claim 1 analyzer to measure the average pore size bubble point pressure of actual ultra filtration membrane, wherein actual ultra filtration membrane is identical with sample ultra filtration membrane model;
S5, based on Laplace equation d=4k σ cos θ/p, with the k that calculate to obtain among the step S3 as constant, with the average pore size bubble point pressure substitution p of the actual ultra filtration membrane measured among the step S4, thereby calculate the average pore size of actual ultra filtration membrane.
4. ultra filtration membrane average pore size assay method as claimed in claim 3 is characterized in that the enlargement factor of described scanning electron microscope is 100～650000 times.
5. ultra filtration membrane average pore size assay method as claimed in claim 3 is characterized in that the micropore size of described ultra filtration membrane is in 0.01～0.1 micrometer range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010579477 CN102087103B (en) | 2010-12-08 | 2010-12-08 | Ultrafiltration membrane average pore size determination method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010579477 CN102087103B (en) | 2010-12-08 | 2010-12-08 | Ultrafiltration membrane average pore size determination method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102087103A true CN102087103A (en) | 2011-06-08 |
| CN102087103B CN102087103B (en) | 2013-07-31 |
Family
ID=44099008
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010579477 Active CN102087103B (en) | 2010-12-08 | 2010-12-08 | Ultrafiltration membrane average pore size determination method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102087103B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102944262A (en) * | 2012-10-31 | 2013-02-27 | 北京控制工程研究所 | Method for determining corresponding relation between absolute filter precision and bubble breaking point |
| CN105080349A (en) * | 2014-05-23 | 2015-11-25 | 深圳市嘉泉膜滤设备有限公司 | Onsite rapid detection method of membrane pore size of plate ultrafiltration membrane |
| CN106823823A (en) * | 2017-02-27 | 2017-06-13 | 中国人民大学 | A kind of method for determining supermicro filtration membrane pore size and pore size distribution |
| CN108507924A (en) * | 2018-03-30 | 2018-09-07 | 华中科技大学 | A kind of integrity of ultrafiltration membrane recognition methods and device |
| CN112051198A (en) * | 2020-08-03 | 2020-12-08 | 江苏省科建成套设备有限公司 | Quantitative evaluation method for pore diameter of porous membrane |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3312729A1 (en) * | 1983-04-08 | 1984-10-11 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München | Method and measurement chamber for determining the pore diameter of micro- and ultrafiltration membranes |
| US20080110243A1 (en) * | 2006-11-14 | 2008-05-15 | Millipore Corporation | Rapid integrity testing of porous materials |
| CN101435763A (en) * | 2008-12-23 | 2009-05-20 | 南京工业大学 | Method for measuring diameter distribution of porous material surface orifice |
| CN201262547Y (en) * | 2008-09-23 | 2009-06-24 | 中国科学院上海应用物理研究所 | Filtering film aperture measurer |
-
2010
- 2010-12-08 CN CN 201010579477 patent/CN102087103B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3312729A1 (en) * | 1983-04-08 | 1984-10-11 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München | Method and measurement chamber for determining the pore diameter of micro- and ultrafiltration membranes |
| US20080110243A1 (en) * | 2006-11-14 | 2008-05-15 | Millipore Corporation | Rapid integrity testing of porous materials |
| CN201262547Y (en) * | 2008-09-23 | 2009-06-24 | 中国科学院上海应用物理研究所 | Filtering film aperture measurer |
| CN101435763A (en) * | 2008-12-23 | 2009-05-20 | 南京工业大学 | Method for measuring diameter distribution of porous material surface orifice |
Non-Patent Citations (1)
| Title |
|---|
| 《膜科学与技术》 19990228 郑翠萍等 用库尔特仪（COULTER POROMETER Ⅱ）测试微孔膜的性能 31-33 1-2 第19卷, 第1期 2 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102944262A (en) * | 2012-10-31 | 2013-02-27 | 北京控制工程研究所 | Method for determining corresponding relation between absolute filter precision and bubble breaking point |
| CN102944262B (en) * | 2012-10-31 | 2015-07-08 | 北京控制工程研究所 | Method for determining corresponding relation between absolute filter precision and bubble breaking point |
| CN105080349A (en) * | 2014-05-23 | 2015-11-25 | 深圳市嘉泉膜滤设备有限公司 | Onsite rapid detection method of membrane pore size of plate ultrafiltration membrane |
| CN106823823A (en) * | 2017-02-27 | 2017-06-13 | 中国人民大学 | A kind of method for determining supermicro filtration membrane pore size and pore size distribution |
| CN106823823B (en) * | 2017-02-27 | 2019-08-09 | 中国人民大学 | A method of measurement supermicro filtration membrane pore size and pore size distribution |
| CN108507924A (en) * | 2018-03-30 | 2018-09-07 | 华中科技大学 | A kind of integrity of ultrafiltration membrane recognition methods and device |
| CN108507924B (en) * | 2018-03-30 | 2023-08-04 | 华中科技大学 | Ultrafiltration membrane integrity recognition method and device |
| CN112051198A (en) * | 2020-08-03 | 2020-12-08 | 江苏省科建成套设备有限公司 | Quantitative evaluation method for pore diameter of porous membrane |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102087103B (en) | 2013-07-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102087103B (en) | Ultrafiltration membrane average pore size determination method | |
| DE60004021T2 (en) | METHOD AND DEVICE FOR TESTING MEMBRANE FILTERS | |
| Chen et al. | Fabrication and characterization of a novel nanofiltration membrane by the interfacial polymerization of 1, 4-diaminocyclohexane (DCH) and trimesoyl chloride (TMC) | |
| US5282380A (en) | Integrity test for membranes | |
| Agarwal et al. | Neck-size distributions of through-pores in polymer membranes | |
| CN109100278A (en) | A kind of apparent permeability calculation method considering shale pore-size distribution feature | |
| Lauterböck et al. | Impact of characteristic membrane parameters on the transfer rate of ammonia in membrane contactor application | |
| Alhadidi et al. | The influence of membrane properties on the Silt Density Index | |
| Masuelli | Ultrafiltration of oil/water emulsions using PVDF/PC blend membranes | |
| Tanis-Kanbur et al. | Membrane characterization via evapoporometry (EP) and liquid-liquid displacement porosimetry (LLDP) techniques | |
| JP4666600B2 (en) | Water evaluation method | |
| Eljaddi et al. | Wetting of photoplasmonic PVDF/silver membranes in photothermal membrane distillation: Identification of wetting mechanisms and comparison of wetting dynamics | |
| Zhu et al. | Cake properties as a function of time and location in microfiltration of activated sludge suspension from membrane bioreactors (MBRs) | |
| CN105334293A (en) | Flow state identification method and device for dense gas in multiple media | |
| CN201262547Y (en) | Filtering film aperture measurer | |
| CN112051198A (en) | Quantitative evaluation method for pore diameter of porous membrane | |
| JP6052866B2 (en) | Water treatment method | |
| JP5037758B2 (en) | Membrane module integrity inspection method | |
| CN213091444U (en) | Quantitative evaluation device for pore diameter of porous membrane | |
| TWI409448B (en) | Process for measurements of concentration of dissolved organic nitrogen (don) with low concentration in water | |
| CN110243714B (en) | Method for determining hydrodynamic size of polymer | |
| CN103432906B (en) | Improve the method for scaling of filters | |
| CN112098572B (en) | Method for detecting low-concentration polymer in polymer flooding produced sewage | |
| Elrouby et al. | Low-Cost Production of 3D Printed Lab-on Chip (LOC) Device for Oil-in-Water Emulsion Separation | |
| Xie | Simulation of reverse osmosis and osmotically driven membrane processes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |