GB2348503A - Monitoring the particulate or solids content of a fluid using a membrane or filter method - Google Patents
Monitoring the particulate or solids content of a fluid using a membrane or filter method Download PDFInfo
- Publication number
- GB2348503A GB2348503A GB0003761A GB0003761A GB2348503A GB 2348503 A GB2348503 A GB 2348503A GB 0003761 A GB0003761 A GB 0003761A GB 0003761 A GB0003761 A GB 0003761A GB 2348503 A GB2348503 A GB 2348503A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fluid
- membrane
- flow rate
- measuring means
- pressure
- 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- Withdrawn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
- 239000012530 fluid Substances 0.000 title claims abstract description 86
- 239000012528 membrane Substances 0.000 title claims abstract description 69
- 238000012544 monitoring process Methods 0.000 title claims abstract description 8
- 238000000034 method Methods 0.000 title claims description 24
- 239000007787 solid Substances 0.000 title description 2
- 239000011148 porous material Substances 0.000 claims abstract description 10
- 238000012360 testing method Methods 0.000 claims description 45
- 238000011109 contamination Methods 0.000 claims description 16
- 238000005259 measurement Methods 0.000 claims description 11
- 238000007619 statistical method Methods 0.000 claims description 3
- 238000009285 membrane fouling Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 12
- 239000002245 particle Substances 0.000 abstract description 10
- 230000003749 cleanliness Effects 0.000 abstract 1
- 238000000149 argon plasma sintering Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- 239000000356 contaminant Substances 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 238000012538 light obscuration Methods 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 235000013405 beer Nutrition 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000009530 blood pressure measurement Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 210000002268 wool Anatomy 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
Landscapes
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
A fluid monitor for ascertaining the level of cleanliness of water (fluid) comprising an inlet (80) and an outlet (90) to allow fluid to enter and exit the fluid monitor respectively; a restricting means (60) for restricting the flow rate through the fluid monitor; first and second flow control devices (10, 20) for directing the flow of the fluid; and a membrane (30) which prevents particles greater than the size of pores in the membrane (30) from passing through it. In addition, a first pressure measuring means (40) for monitoring the differential pressure across the membrane (30). A flow measuring means (70) and a second pressure measuring means (50) are used for making continuous flow rate readings to correct the differential pressure readings for flow rate variation. A storage area for logging results and data past and present, a processor for making an analysis of the data logged, and a display for displaying the results of the analysis are also provided.
Description
Fluid Monitor
The present invention relates to a device for monitoring a level of particulates in a fluid, more particularly, but not exclusively, ~ In many systems it is important to know the level of undissolved particulates in a fluid. In particular, it is commonly required to monitor particulate contamination of water, whether this is to ascertain the efficiency of filters or to determine if the contamination levels are within acceptable limits.
Present methods of measuring levels of particulate contamination in water are as follows.
In one method, particulates are counted by using a membrane and microscope, which is very labour intensive and results in samples being taken infrequently, and with long delays.
In another method, turbidity is measured using turbidimeters which measure the light scattered by the particulates, and the numbers of particulates are determined by derivation from the amount of light scattering. Such methods have been used for example in breweries to assess beer cloudiness. These methods have the advantage that they can be used continuously online but suffer from several disadvantages regarding assumptions of particle sphericity and opacity to light, and the characteristics and stability of the light source.
In another method, a coherent monochromatic light source (a laser) counts particulates passing a very small window by light obscuration. This method is an improvement on light scattering techniques but does not overcome the sphericity and opacity assumptions, and the equipment is very expensive.
Also, filter blocking methods are described in
EP0116580 and US5095740. These methods measure either time-to-block or volume-to-block to a certain backpressure increase against the membrane. In general, such methods suffer from the disadvantages that the back-pressure results are also dependent on the temperature, the viscosity, and turbulence or flow fluctuations in the fluid to be measured. The use of very accurate pumping devices in these methods partly overcomes the erratic flow disadvantages but adds substantially to the cost.
The inventors of the present invention have founda way to use a filter-blocking method that avoids the disadvantages of the light-scattering and obscuration methods and of the other filter-blocking methods, and also avoids the use of any form of pumping.
Broadly, the present invention provides a way to measure particulates in a fluid by measuring the differential pressure across (i. e. either side of) a membrane using a pressure transducer; by measuring time-series fluid fluctuations, using a second differential pressure transducer across a tapered duct (venturi); by discarding results that are not statistically acceptable and so avoiding dependencies due to flow, temperature and viscosity; and by using process line pressure head to cause sample flow, thus obviating the need for any pumping mechanism.
According to one aspect of the present invention, there is provided a fluid monitor for monitoring a particulate content of a fluid, comprising :
an inlet and an outlet to allow fluid to enter and exit the fluid monitor respectively;
a membrane which is permeable by the fluid but impermeable to at least some of the particulates in the fluid, provided between the inlet and outlet;
pressure measuring means for measuring a pressure difference either side of the membrane;
flow rate measuring means for measuring both the flow rate and volume of fluid passing through the membrane;
flow control means arranged to selectively direct the fluid through the membrane and the flow rate measuring means in a forward direction, or to direct the fluid at least through the membrane in a reverse direction; and
control means arranged to control the flow control means, and to acquire data from the pressure measuring means and the flow rate measuring means to perform a test mode including measuring the pressure differences either side of and the flow rate through the membrane whilst directing the fluid through the membrane in the forward direction, and a back flush mode of directing the fluid through the membrane in the reverse direction.
Preferably, the flow control means is further arranged to selectively direct the fluid to bypass the membrane and the tapered duct, and the control means is arranged to control the flow control means such that the fluid normally bypasses the membrane and tapered duct.
The control means may be arranged to carry out a test cycle in which: the back flush mode is first performed; the test mode is then performed; and after completion of the test mode, the back flush mode is again performed followed by the bypass mode.
In a preferred embodiment of the invention, the test mode comprises a prime phase followed by a test phase, the prime phase providing for flow stabilisation as determined by the tapered duct, and the test phase comprising taking time-series differential pressure measurements using the pressure measuring means after the flow conditions are statistically stable.
The fluid monitor may further include a means for storing the measurements taken in previous test cycles and a means for comparing these measurements to assess the degree of membrane fouling.
In the preferred embodiment, flow rate measuring means are provided for measuring the flow rate of the fluid through the membrane in the forward direction, and correcting means for correcting a ratio of the pressure differences measured by the pressure measuring means, using the measured flow rate.
Conveniently, the membrane of the fluid monitor consists of a mesh having pores sufficiently small to block passage of the particulates. The present invention is applicable to particle and pore sizes anywhere in the sub-micron to mm range, more typically in the range 1-100 microns, but may also be applied in the nanometre range.
A restricting means may be provided for restricting a maximum flow rate of the fluid through the fluid monitor.
In addition, a display may be included for displaying the results of the measurements taken by said pressure measuring means, and/or an interface for sending elsewhere the results of the measurements taken by said pressure measuring means.
In addition, preferably, the control means has a timer which allows the phases within the test cycle to be carried out at predetermined intervals. Typically, the intervals are determined by setting the length of the bypass mode, which can have a duration between 1 minute and 24 hours, although shorter durations down to a few seconds are conceivable.
According to a second aspect of the present invention, there is provided a method for monitoring the particulate content of a fluid, comprising the steps of:
directing the fluid to a membrane, which is permeable by the fluid but impermeable to at least some of the particulates in the fluid;
performing a test mode which includes measuring the pressure difference either side of the membrane before and after a contamination interval whilst directing the fluid through the membrane in a forward direction;
directing the fluid through a tapered duct in series with the membrane, and measuring pressure differences either side of the tapered duct;
calculating flow rate data and performing statistical analyses on the flow rate data;
performing a back flush mode by directing the fluid through the membrane in a reverse direction;
calculating the particulate content of the fluid from the measured pressure difference readings either side of the membrane before and after the contamination interval whilst correcting for flow fluctuations; and
performing in a bypass mode to allow the membrane to rest.
Thus, the present invention can provide an"on line"monitoring device intended to determine the particulate content of fluids in a wide range of applications. The present invention gives an indication of the quantity of undissolved (e. g solid) particulates in a fluid under test, such as a contaminant in a water sample based on the degree of blockage of the membrane (e. g. mesh). The monitor uses a simple"rate of mesh blockage process"to measure the amount of contamination in the water under test. The results are preferably determined ratiometrically (i. e. using consecutive relative values only) so that the method is self-calibrating and the apparatus does not require calibration against an unblocked mesh.
The present invention is concerned with providing an inexpensive and very accurate method of providing real time fluid monitoring in a simple and speedy manner using the filter blockage principle. The unit is designed as a stand alone device although it has the ability to be daisy chained together using an interface and can report to and be controlled from a remote location via the interface. The unit is ideally-able to operate over a wide temperature range without need for support for long periods (e. g. several months depending on the test cycle interval) subject to the particulate content of the fluid. The membrane can be in the form of a consumable cartridge which is easily replaced by the user.
A detailed description of one embodiment of the invention will now be given by way of example with reference to the accompanying drawings, in which:
Fig. 1 is a diagram showing the flow path of the fluid during back flushing (back flush mode);
Fig. 2 is a diagram showing the flow path of the fluid during testing (test mode); and
Fig. 3 is a diagram showing the flow path of fluid during the by-pass mode.
In the illustrated embodiment, water is sampled by the monitor through the inlet 80. As there is no means within the apparatus of producing fluid flow through the unit, it requires a pressure drop across the unit sufficient to produce a flow of water through the unit.
The flow rate allowed through the example unit is restricted to a maximum of 400 ml/min to prevent damage to the components. This maximum flow rate is achieved by using a restrictor valve 60 which has no feedback or control options. The flow rate below 400 ml/min may vary depending on the degree of contamination, the pressure drop across the unit, temperature, and viscosity. The water that has been tested is directed to waste through the outlet 90. As can be seen in
Figures 1 to 3 the water flow path is controlled by the flow control devices 10,20 together constituting a flow control means for the fluid monitor. A control unit 100 (such as a microcomputer) performs overall control of the flow control means, as well as controlling and taking readings from pressure measuring means 40 and 50 explained below, and calculating-- particle count.
The present invention performs five stages in three modes to produce a result. The sequence is as follows:
A first mode is known as the back flush mode-the unit performs a back flush to remove contaminants from the membrane 30, trapped in the previous cycle. After completing the test mode, a back flush is performed again to clean the membrane 30 once more, i. e. remove particles from the membrane 30.
A second mode is known as the test mode-this mode is made up of a prime phase and a test phase, both of which use the same flow path. The prime phase lasts for a short period of time such as 10 seconds and is used to ensure that the fluid system is stable. The test phase performs the actual test only when the system is stable, and produces a result correct for the stable flow conditions.
A third mode is known as the by-pass mode-the period of time for which the by-pass mode is set can be determined by the user. This allows the membrane to rest and provides for the whole test cycle interval to be varied by the minute, hour, or day depending on the user's requirements.
If the flow control devices 10,20 are in the positions shown in Fig. 1 then the flow is directed through the membrane 30 in the reverse direction, and the membrane 30 is back flushed removing particles trapped during the previous test cycle.
During the back flushing mode the differential pressure either side of the membrane 30 is measured by the first pressure measuring means 40 so that when the minimum differential pressure is reached, the back flush is stopped and another test mode is performed or the by-pass mode is triggered. For a new mesh where there is no contamination to flush away, the back=flush mode is less than one second in duration.
If the flow control devices 10,20 are in the positions indicated in Fig. 2 then the flow is directed to the membrane 30 in the forward direction and a test mode is performed. The test mode is made up of two phases, the prime phase and the test phase.
During the test mode any particulate within the water sampled, of greater size than the pore size in the membrane 30, is trapped by the membrane 30. The differential pressure either side of the membrane 30 is constantly logged by a first pressure measuring means 40. A differential pressure measuring means 50 and a flow modulating means 70 form a flow rate measuring means. The second pressure measuring means 50 measures the changes in differential pressure across the flow modulating means 70 or venturi-tube. By using
Bernoulli's principle on the data from the second differential pressure transducer 50, both flow rate readings and volume measurements are derived.
In the prime phase of the test mode, the flow rate of the sample is continuously calculated until a processor, by use of statistical analysis, builds up confidence in the stability of the flow result. During the prime phase the differential pressure from the first pressure measuring means 40 drops as particles deposited on the reverse side of the membrane 30 are flushed off. The differential pressure reaches a minimum and then rises as the membrane 30 begins tc trap new particles.
During the test phase, a first confident differential pressure reading from either side of the membrane is recorded and logged. Contamination is allowed to continue to block the membrane. Confidence in the flow rate results continues to be monitored and a second confident differential pressure reading is recorded after ten seconds, and logged. The rate'ouf rise of differential pressure corrected for volume is used to derive the contamination C (amount of particles greater than pore size) of the water being tested, using the well-known formula:
C = (1-dpl/dp2). n. a/v where
dpl = first confident differential pressure reading either side of membrane dp2 = second confident differential pressure reading either side of membrane
n = number of pores per unit area in membrane
a = area of membrane
v = volume flowed during the contamination interval, measured by flow rate measuring means.
The count calculation is ratiometric and does not depend on obtaining a value of the new-mesh differential pressure (dpO) ; thus, the monitor is selfcalibrating. Alternatively, however, it would be possible if desired to employ a calibration method, replacing the value dpl by the new-mesh initial value dpO.
At this time the contamination count value is calculated and the result is displayed on a display means and may be exported. The unit now goes into back flush mode. Time or pressure criteria only curtail a test in abnormal conditions e. g. a high differential pressure which will stop a test to protect the pressure measuring means 40,50.
If the flow control means 10,20 are in the position shown in Fig. 3 the by-pass mode is set. This is the fail safe mode so that in the case of power down the valves 10, 20 return to these positions and the unit is protected from pressure build up.
In the example used, the membrane 30 used is a high precision woven polyester mesh, the weave of which produces a uniform array of pores of known size and open area (the open area is the proportion of the'total mesh area which is occupied by the pores). The effect on the differential pressure across the membrane 30 is therefore consistent, for any of the pores within the open area.
It will be apparent that several modifications are possible within the scope of the present invention. In particular, although the above-described embodiment refers to particulate contamination of water, the invention can be applied to other fluids in which desirable or undesirable undissolved particles are present. Also, although the above example employs a woven polyester mesh, the present invention can employ any other kind of membrane or filter including a metal mesh (e. g. stainless steel), moulded or punched mesh, paper filter, cast sponge, stainless steel wool, packed column and so forth.
Claims (16)
1. A fluid monitor for monitoring a particulate content of a fluid, comprising:
an inlet (80) and an outlet (90) to allow fluid to enter and exit the fluid monitor respectively ; a membrane (30) which is permeable by the fluid but impermeable to at least some of the particulates in the fluid, provided between the inlet (80) and outlet (90) ; pressure measuring means (40) for measuring a pressure difference either side of the membrane;
flow rate measuring means (50,70) for measuring both the flow rate and volume of fluid passing through the membrane (30) ; flow control means (10, 20) arranged to selectively direct the fluid through the membrane (30) and the flow rate measuring means (50,70) in a forward direction, or to direct the fluid at least through the membrane (30) in a reverse direction; and
control means (100) arranged to control the flow control means (10,20), and to acquire data from the pressure measuring means (40) and the flow rate measuring means (50,70) to perform a test mode including measuring the pressure differences either side of and the flow rate through the membrane (30) whilst directing the fluid through the membrane (30) in the forward direction, and a back flush mode of directing the fluid through the membrane (30) in the reverse direction.
2. A fluid monitor according to claim 1, wherein the flow control means (10,20) are further arranged to selectively direct the fluid to bypass the membrane (30) and the flow rate measuring means (50,70).
3. A fluid monitor according to claim 2, wherein the control means (100) is arranged to control the flow control means (10, 20) such that the fluid normally bypasses the membrane (30).
4. A fluid monitor according to claim 1,2, or 3, wherein the control means (100) is arranged to carry out a test cycle in which:
the back flush mode is first performed ; the test mode is then performed;
after completion of the test mode, the back flush mode is again performed.
5. A fluid monitor according to claim 4, wherein:
the test mode comprises a prime phase followed by a test phase, the prime phase for allowing the flow through the membrane (30) to become stable, and the test phase comprising taking measurements (dpl, dp2) using the pressure measuring means (40) and flow rate measuring means (50,70).
6. A fluid monitor according to claim 4 or 5, further comprising a means for storing measurements within the test phase of the test mode and means for comparing these measurements to calculate the degree of membrane fouling.
7. A fluid monitor according to any preceding claim, further comprising calculating means (100) for calculating a contamination count, using the flow rates and volumes measured by the flow rate measuring means (50,70) and the pressure differences measured by the pressure measuring means (40).
8. A fluid monitor according to any preceding claim, wherein the membrane (30) consists of a mesh having pores sufficiently small to block passage of said particulates.
9. A fluid monitor according to any preceding claim, further comprising a restricting means (60) for restricting a maximum flow rate of the fluid through the fluid monitor.
10. A fluid monitor according to any preceding claim, further comprising a display for displaying the results of the measurements taken by said pressure measuring means (40).
11. A fluid monitor according to any preceding claim, further comprising a interface for sendingelsewhere the results of the measurements taken by said pressure measuring means (40) and said flow rate measuring means (50,70).
12. A fluid monitor according to any preceding claim, further comprising a timer which determines the interval between successive pressure difference measurements by the pressure measuring means (40) carried out during the test phase of the test mode.
13. A fluid monitor according to claim 4,5, or 6, wherein the control means has a timer which allows the test cycle to be carried out at a predetermined interval.
14. A fluid monitor substantially as hereinbefore described with reference to the accompanying drawings.
15. A method for monitoring the particulate content of a fluid, comprising the steps of:
directing the fluid to a membrane (30), which is permeable by the fluid but impermeable to at least some of the particulates in the fluid;
performing a test mode which includes measuring the pressure difference either side of the membrane before and after a contamination interval whilst directing the fluid through the membrane in a forward direction;
directing the fluid through a tapered duct (70) in series with the membrane (30), and measuring pressure differences either side of the tapered duct;
calculating flow rate data and performing statistical analyses on the flow rate data;
performing a back flush mode by directing the fluid through the membrane (30) in a reverse direction;
deriving the particulate content of the fluid from the measured pressure difference readings (dpi, dp2) either side of the membrane before and after the contamination interval whilst correcting for flow rate variations; and
performing in a bypass mode to allow the membrane (30) to rest.
16. A method according to claim 15, comprising an initial step of measuring an initial pressure difference (dpO) which is used to calibrate the later test mode.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB9904043.8A GB9904043D0 (en) | 1999-02-22 | 1999-02-22 | Fluid monitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB0003761D0 GB0003761D0 (en) | 2000-04-05 |
| GB2348503A true GB2348503A (en) | 2000-10-04 |
Family
ID=10848271
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB9904043.8A Ceased GB9904043D0 (en) | 1999-02-22 | 1999-02-22 | Fluid monitor |
| GB0003761A Withdrawn GB2348503A (en) | 1999-02-22 | 2000-02-17 | Monitoring the particulate or solids content of a fluid using a membrane or filter method |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB9904043.8A Ceased GB9904043D0 (en) | 1999-02-22 | 1999-02-22 | Fluid monitor |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB9904043D0 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2361548A (en) * | 2000-03-18 | 2001-10-24 | John Barnes | Determining the level of particulate contamination in a fluid power system |
| WO2013191740A1 (en) * | 2012-06-19 | 2013-12-27 | Spectro, Inc. | Filtration particle quantifier |
| CN107764705A (en) * | 2017-09-28 | 2018-03-06 | 珠海格力电器股份有限公司 | The detection method of water purifier and its cleannes, device and system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1984000816A1 (en) * | 1982-08-13 | 1984-03-01 | Secretary Trade Ind Brit | Contamination level indicator |
| GB2138565A (en) * | 1983-03-25 | 1984-10-24 | Central Electr Generat Board | Apparatus for monitoring particulate matter |
| US5385043A (en) * | 1993-10-15 | 1995-01-31 | Diagnetics, Inc. | Contamination measurement apparatus |
-
1999
- 1999-02-22 GB GBGB9904043.8A patent/GB9904043D0/en not_active Ceased
-
2000
- 2000-02-17 GB GB0003761A patent/GB2348503A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1984000816A1 (en) * | 1982-08-13 | 1984-03-01 | Secretary Trade Ind Brit | Contamination level indicator |
| GB2138565A (en) * | 1983-03-25 | 1984-10-24 | Central Electr Generat Board | Apparatus for monitoring particulate matter |
| US5385043A (en) * | 1993-10-15 | 1995-01-31 | Diagnetics, Inc. | Contamination measurement apparatus |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2361548A (en) * | 2000-03-18 | 2001-10-24 | John Barnes | Determining the level of particulate contamination in a fluid power system |
| GB2361548B (en) * | 2000-03-18 | 2002-04-10 | John Barnes | Contaminant communicator system |
| WO2013191740A1 (en) * | 2012-06-19 | 2013-12-27 | Spectro, Inc. | Filtration particle quantifier |
| US9176041B2 (en) | 2012-06-19 | 2015-11-03 | Spectro Scientific, Inc. | Filtration particle quantifier |
| CN107764705A (en) * | 2017-09-28 | 2018-03-06 | 珠海格力电器股份有限公司 | The detection method of water purifier and its cleannes, device and system |
| CN107764705B (en) * | 2017-09-28 | 2020-06-16 | 珠海格力电器股份有限公司 | Water purifier and cleanliness detection method, device and system thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9904043D0 (en) | 1999-04-14 |
| GB0003761D0 (en) | 2000-04-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4583396A (en) | Contamination level indicator | |
| AU733171B2 (en) | Filter life measurement | |
| EP0814887B1 (en) | Filtration monitoring and control system | |
| JP2001293466A (en) | Water cleaning system for sensing and controlling distributing quantity | |
| CA2501530C (en) | Continuous flow chemical metering apparatus | |
| US5798699A (en) | Method for monitoring and selectively sampling a fluid flow stream | |
| US3452586A (en) | Automatic fuel filter monitor | |
| US6966994B2 (en) | Contamination control for engines | |
| GB2348503A (en) | Monitoring the particulate or solids content of a fluid using a membrane or filter method | |
| KR20180067813A (en) | Apparatus for automatic cleaning filter for pipe | |
| JP7072793B2 (en) | Underwater radioactivity measuring device with early warning function by turbidity estimation, underwater radioactivity measuring system | |
| US4468954A (en) | Device for determining the concentration of suspended solid contaminants in a fluid | |
| US6230551B1 (en) | Evaluation of particulate contaminants | |
| US6474144B1 (en) | Determining the level of particulate contamination in a fluid power system | |
| GB2408100A (en) | Acoustic detection of foam formation in pipe flows | |
| EP0589970A1 (en) | Monitoring apparatus. | |
| US6248243B1 (en) | Solids monitoring filter meter | |
| US2998520A (en) | Fluid flow regulator | |
| US10481059B2 (en) | System and method for remote monitoring of solid contaminant in fluids | |
| JPH10185813A (en) | Turbidity/chromaticity meter | |
| JPH11230905A (en) | Turbidimeter | |
| JP2003202259A (en) | Gas meter and method for inspecting gas meter | |
| Mackay | Automated filtration relies on instrumentation | |
| CA3206102A1 (en) | Method and system for selection and monitoring of a steam trap using deep neural network | |
| WO2009138360A2 (en) | Radioactivity monitoring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |