EP1877777A1 - System und verfahren zur partikelstrom-charakterisierung - Google Patents
System und verfahren zur partikelstrom-charakterisierungInfo
- Publication number
- EP1877777A1 EP1877777A1 EP05759810A EP05759810A EP1877777A1 EP 1877777 A1 EP1877777 A1 EP 1877777A1 EP 05759810 A EP05759810 A EP 05759810A EP 05759810 A EP05759810 A EP 05759810A EP 1877777 A1 EP1877777 A1 EP 1877777A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- camera
- sample
- particle
- particles
- gap
- 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- Withdrawn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
- 239000002245 particle Substances 0.000 title claims abstract description 179
- 238000000034 method Methods 0.000 title claims abstract description 29
- 238000012512 characterization method Methods 0.000 title claims abstract description 12
- 238000004458 analytical method Methods 0.000 claims abstract description 7
- 238000001514 detection method Methods 0.000 claims description 26
- 230000005670 electromagnetic radiation Effects 0.000 claims description 20
- 238000012545 processing Methods 0.000 claims description 18
- 238000004140 cleaning Methods 0.000 claims description 14
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- 239000000463 material Substances 0.000 abstract description 15
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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
- G01N15/10—Investigating individual particles
- G01N15/14—Optical investigation techniques, e.g. flow cytometry
- G01N15/1468—Optical investigation techniques, e.g. flow cytometry with spatial resolution of the texture or inner structure of the particle
- G01N15/147—Optical investigation techniques, e.g. flow cytometry with spatial resolution of the texture or inner structure of the particle the analysis being performed on a sample stream
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C25/00—Control arrangements specially adapted for crushing or disintegrating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C4/00—Crushing or disintegrating by roller mills
- B02C4/28—Details
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C4/00—Crushing or disintegrating by roller mills
- B02C4/28—Details
- B02C4/32—Adjusting, applying pressure to, or controlling the distance between, milling members
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/10—Devices for withdrawing samples in the liquid or fluent state
- G01N1/20—Devices for withdrawing samples in the liquid or fluent state for flowing or falling materials
-
- 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
- G01N15/10—Investigating individual particles
- G01N15/14—Optical investigation techniques, e.g. flow cytometry
- G01N15/1429—Signal processing
- G01N15/1433—Signal processing using image recognition
-
- 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
- G01N2015/0019—Means for transferring or separating particles prior to analysis, e.g. hoppers or particle conveyors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/02—Food
- G01N33/10—Starch-containing substances, e.g. dough
Definitions
- the invention relates to a system and a method for characterizing a particle flow, wherein at least the shape of the dimension or the movement behavior of the individual particles is detected.
- the particle stream is a stream of pulverulent to granular bulk material, in particular grain, flour, sugar, pigments, chemicals, pharmaceuticals, dust emissions, soot particles, toner powder, etc.
- the granular material When grinding granular material, e.g. Wheat or sugar, in a roller mill, the granular material is crushed between the rolls of the roll pair.
- the material to be ground usually has to be passed through such a passage several times, with grading being carried out by air classification and sieving in between.
- grading being carried out by air classification and sieving in between.
- the grinding effect of a passage depends mainly on the gap distance between the two rolls of a pair of rolls.
- roller mill operating parameters which influence the grinding effect of a passage. It is therefore desirable to obtain a characterization of the regrind which exits after a certain passage. If a deviation of the ground material from a desired grinding stock characteristic occurs, a correction of the gap distance or, if appropriate, of a further roller mill operating parameter can be carried out on the basis of this deviation in order to compensate for the deviation as quickly as possible.
- the object of the invention is to provide a system and a method which makes it possible to characterize a particle stream, in particular the ground material emerging from a grinding passage, in a roll mill. This object is achieved by the system according to claim 1 and the method according to claim 33.
- the inventive system comprises a removal means for removing a sample from the particle stream; a performance section for conveying and presenting the sampled sample; a detecting means for detecting the sample conveyed through the presentation section; and an analyzing means for analyzing the detected sample.
- the method according to the invention comprises the following steps: taking a sample from the particle stream; Conveying and presenting the sampled sample in a performance section; Detecting the sample conveyed through the presentation section; and analyzing the detected sample.
- a deagglomeration section for deagglomerating particle agglomerates in the sample is provided downstream of the removal means and upstream of or in the presentation section. This prevents multiple particle agglomerates from being erroneously detected and identified as large particles.
- the sampling means may be connected via a pneumatic line to the presentation section such that the sample can be conveyed through the pneumatic conduit and the presentation section along a flow path.
- the system according to the invention can also be attached to a location remote from the roller mill within a mill, whereby the design freedom is increased in the design of a mill plant.
- the presentation section has two opposite walls, between which a gap is formed, wherein the two opposite walls are preferably mutually parallel planar surfaces.
- the pneumatic line mentioned above opens into a gap in the gap formed between the opposing walls, wherein the flow path in the mouth region preferably has a change in direction.
- the change in direction of the flow path is in particular between 30 ° and 90 ° and is preferably between 80 ° and 90 °. This leads to particularly large momentum changes in the entrained particles in their deflecting impacts and thus to a particularly pronounced impact effect.
- the detection means has a camera for detecting electromagnetic radiation or electromagnetic frequencies, in particular optical frequencies, wherein the camera is preferably directed into the gap or to the gap.
- the opposite walls of the presentation section are permeable to electromagnetic radiation detectable by the camera, in particular optical frequencies.
- the camera can optionally be placed on either side of the gap behind one of the walls.
- the camera is arranged on one side of the gap on one of the two permeable walls, and a source of electromagnetic radiation, in particular a light source, for the detectable by the camera electromagnetic radiation on the other side of the gap on the gap the other of the two permeable walls is arranged.
- a source of electromagnetic radiation in particular a light source
- the particles of the sample conveyed through the gap can be irradiated by the electromagnetic radiation, and the shadow projection or the projection of the particles of the sample reaches the field of view of the camera.
- the first wall for detectable by the camera electromagnetic radiation, in particular optical frequencies permeable, while the second wall for the detectable by the camera electromagnetic frequencies, in particular optical frequencies, impermeable and more absorbent than the regrind particles is.
- the camera is disposed on the permeable wall on one side of the gap, and a source of electromagnetic radiation, in particular a light source, for the electromagnetic radiation detectable by the camera is on the same side of the gap on the permeable wall arranged.
- a source of electromagnetic radiation in particular a light source, for the electromagnetic radiation detectable by the camera is on the same side of the gap on the permeable wall arranged.
- the gap-side surface of the second wall has a stronger absorption of the electromagnetic radiation emitted by the source than the surfaces of the particles. This ensures that there is enough contrast between the reflective particles moving in front of the gap-side surface and the light reflected from the wall so that effortless detection of the imaged particles is possible and the subsequent image processing is substantially facilitated. This saves complex and time-consuming filter processes in image processing.
- the two opposite walls each have a cleaning device associated with the two opposite walls can be freed from adhering to them particles. This ensures that not too many dormant, ie adhering to one or the other wall particles are imaged into the camera.
- the particle size distribution of the particles adhering to the walls is usually different than that of the particles entrained in the particle stream. If you dispense with a distinction between stationary and moving particles in the detection and processing of the particle stream image information Therefore, such a wall cleaning should be carried out regularly to "shake off" the particles adhering to the walls.
- the cleaning device may be a source of vibration, in particular an ultrasonic source, which is in each case rigidly connected to the two opposite walls in order to be able to vibrate the two walls.
- a source of vibration in particular an ultrasonic source, which is in each case rigidly connected to the two opposite walls in order to be able to vibrate the two walls.
- the cleaning device can also be a vibration source, in particular an ultrasonic source, with which the gaseous medium can be vibrated between the two opposite walls.
- a vibration source in particular an ultrasonic source, with which the gaseous medium can be vibrated between the two opposite walls.
- the deagglomeration section is preferably a baffle in the entrance area of the presentation section.
- the deagglomeration section is preferably a baffle in the entrance area of the presentation section.
- impulse transmission to agglomerates can also contribute to the airborne sound version of the wall cleaning device for deagglomeration of entrained in the air particles, where necessary, one after the other or simultaneously working with different ultrasonic frequencies.
- the change in direction of the flow path is preferably located in the entrance area of the presentation section. As a result, the bouncing occurs shortly before the optical detection of the particle flow, so that the particles are virtually completely deagglomerated.
- the presentation section or the window is larger than the field of view of the camera, several cameras can also each capture a subregion of the presentation section. This allows an averaging of different particle flow images from different locations within the performance section. Should segregation of the particle flow take place at the various subregions, this averaging can be used to compensate at least partially for such segregation, so that the averaged totality of the information from the respective particle flow images for the particle size distribution in FIG total particle flow is representative.
- the plurality of cameras can each be controlled selectively so that selective sections of the particle flow image can be used on the image sensor and averaged.
- the presentation section can essentially correspond to the entire field of view of the camera, with the image sensor of the camera then being selectively controllable, so that selective sections of the particle flow imaging on the image sensor can be used.
- a selective activation preferably takes place purely by chance, in particular by activation by means of a random generator.
- the system according to the invention is associated with a roller mill and comprises a plurality of removal means arranged along the axial direction of a roller passage after the roller passage, wherein preferably a first removal means in the region of the first axial end of the roller passage and a second removal means in the region of the second axial end Roller passage is arranged.
- the light source and the camera are connected to a control device, which can synchronously switch the light source and the camera on and off, so that a sequence of stroboscopic images takes place. It is also possible to provide a plurality of light sources or stroboscopic flash units which can be operated simultaneously but differently, in particular with regard to the duration of the flash and the intensity of the flash.
- the analysis means preferably has an image processing system.
- This image processing system preferably has means for distinguishing between moving particles and particles adhering to the walls in the particles imaged and detected by the camera in the projection mode or in the reflection mode. Then, the adhering to the wall, resting particles can be in the evaluation in the image processing taken into account constant s' such that only the moving particles are used for the evaluation. As a result, a falsification of the particle size distribution of the particle flow is avoided, as described above.
- the mill sample is preferably removed from the mill feed stream leaving the roll passage at various points, so that, as explained above, information about the relative roll orientation of the pair of passages can be obtained.
- the millbase sample thus obtained is then preferably conveyed through the presentation section in a radial flow.
- the radial flow velocity in the radial direction decreases from the inside to the outside.
- the loading of the transport fluid eg pneumatic air
- the transport fluid is radially from the inside to outside substantially constant, ie the number of regrind particles per unit volume is also outwardly substantially constant, so that the probability of particle overlaps in the imaging of the projection image or the reflection image over the radial region is substantially ' constant.
- the loading of the transport fluid can be varied.
- the particle flow passed through the presentation section is detected only in partial areas.
- the evaluation results of the various detection subareas can then be averaged to achieve the most representative possible characterization of the total particle flow.
- the respectively acquired partial areas of the presentation section are selected at random.
- the samples taken are pneumatically conveyed from collection to delivery, preferably with removal, presentation, collection and analysis of the samples being carried out continuously.
- a complete monitoring of the grinding process and the grinding quality by characterizing the Mahlgutstromes produced by the grinding process. This can be used in a particularly advantageous manner for controlling the grinding process, in particular for grinding gap adjustment.
- the detection of the continuous particle flow is expediently carried out stroboscopically by a series of stroboscopic flashes.
- v average flow velocity of the pneumatic medium
- Dmin minimum particle size of a particle
- Dmax maximum particle size of a particle.
- the detection preferably takes place by means of a series of stroboscopic flashes which has a first sub-series of still-picture stroboscopic flashes with a first on-time Ti and a first light intensity L1 and a second sub-series of trajectory stroboscopic flashes with a second on-time T2 and a second light intensity L2, satisfying the following relationship: T2> 2 T1.
- a turn-off period T3 between a still-picture strobe flash and a trajectory strobe flash satisfies the relation 2 D ⁇ v T3.
- the switch-off duration T3 between the still-picture stroboscopic flash and the trajectory strobe flash satisfies the relation 2 D ⁇ v T3 ⁇ 10 D and in particular the relationship 2 D ⁇ v T3 ⁇ 7 D.
- the distance between the respective still image and the respective trajectory is not too large for the moving particles once imaged as a still image and once as a trajectory, so that an unambiguous assignment between the respective still image and the associated respective trajectory of a moving particle is possible.
- the duty T1 of the still-picture strobe flashes should satisfy the relationship v T1 "D, and especially the relationship v T1 ⁇ D / 10.
- the duty T2 of the trajectory strobe flashes should satisfy the relationship v T2> D, and in particular the relationship v T2> 5 D.
- the light intensity L1 of the still-picture strobe flashes and the light intensity L2 of the runway strobe flashes are different from each other. This can also be used to distinguish the resulting still images and trajectory images.
- the particle still images, to which a particle trajectory can be assigned can be stored in a first still image memory, so that the respective particle still image information is stored in a still image memory for each still-image stroboscopic flash and trajectory stroboscopic flash.
- the particle still image information of consecutive still images can then be statistically evaluated, in particular to determine the average particle size D, its standard deviation, and their statistical distribution.
- the representation can be done by means of a distribution function (differentiated) or by histogram (integrated).
- the system according to the invention can be used as a regrind characterization system. It is preferably used in a mill where it is associated with a roller mill to characterize the respective millbase (e.g., flour, sugar, pigments, etc.).
- a roller mill to characterize the respective millbase (e.g., flour, sugar, pigments, etc.).
- this roll mill are also assigned:
- An adjusting device for adjusting the gap distance or possibly another roller mill operating parameter as a function of a deviation between the detected grinding material characteristic and the desired grinding stock characteristic An adjusting device for adjusting the gap distance or possibly another roller mill operating parameter as a function of a deviation between the detected grinding material characteristic and the desired grinding stock characteristic.
- Fig. 1 is a schematic sectional view through a part of a system according to the invention for illustrating the course of the grinding stock flow
- Fig. 2 is a block diagram of another part of the system according to the invention to illustrate its means for detecting and processing regrind information
- Fig. 3 illustrates part of the detection and processing of regrind information
- Fig. 4 shows a specific aspect of the detection and processing of regrind information.
- FIG. 1 shows a schematic sectional view through a part of a system according to the invention in order to illustrate the course of the millbase stream.
- a pair of rollers 2, 4 forms a grinding passage 6 of a roll mill.
- the millbase 1 schematically indicated by bold points, which is, for example, wheat flour with particle sizes in the range of a few 100 .mu.m, arrives after its grinding in the grinding passage 6 in a funnel 8, which opens into a pneumatic line 18.
- the grinding stock 1 is transported via this pneumatic line 18 to a gap 10 which extends between a first wall 20 and a second wall 2 " 2, which are aligned parallel to one another then moves radially outwardly from this mouth region 19 to enter a transition region 28 through which it is pneumatically and gravitationally conveyed downwardly and into another pneumatic conduit 30.
- a camera 12 which is directed to the gap 10.
- a light source 24 which ' passes through the gap 10 through the two walls 20, 22 therethrough.
- the camera 12 detects the projected from the Mahlgutpumblen 1 shadow on their image sensor.
- the light source 24 may alternatively be arranged above the translucent wall 20 next to the camera 12.
- the bottom wall 22 is opaque and has on the side of Split 10 a dark surface.
- the camera 12 detects the light reflected or scattered by the grinding stock particles 1 on their image sensor.
- the light source 24 is operated as a stroboscope.
- the shadows of the grinding stock particles (first version) or the images of the grinding stock particles (second version) are imaged on the image sensor of the camera 12 as still images.
- This Mahlgutstrom-still images represent snapshots of the Mahlgutstromes in the gap 10.
- This image information is supplied to the camera 12 downstream image processing system 14 in which the Mahlgutstrom still images are processed to make statistical statements about the size distribution of Mahlgutpiety can.
- a deagglomeration section 16 in the form of a baffle plate.
- the comminuted particles 1 transported in via the pneumatic line 18 strike against this baffle plate 16 and then undergo a directional deflection by about 90 ° through the conveying air before they enter the gap 10 between the two parallel walls 20, 22.
- agglomerates are effectively dissolved under the Mahlgutpumblen, and arrive de-agglomerated Mahlgutpelle in the gap 10.
- a distortion of the grinding material characterization is prevented by agglomerates in the millbase.
- the pneumatic line 30 opens again into the line leading away from the roller mill (not shown).
- the sampled sample 1 removed is returned to the mill via a suction nozzle (not shown) in order to be further ground, screened or wind-sifted if necessary.
- this "suction" back into the mill cycle by a vacuum cleaner 36 is indicated schematically.
- This branch line 32 includes a throttle valve 34 via which the flow resistance of the branch line 32 is adjustable.
- the grinding stock density must not be too great for optimum operation of the system according to the invention for grinding stock characterization.
- the grind speed, the flash duration and flash intensity of the stroboscope lamp 24 as well as the sensitivity and optical resolution of the camera 12 must be matched to one another in order to obtain sufficiently bright and sharp shadows or images of the grist particles.
- the Mahlgutêt and the radial flow rate decreases radially from the inside to the outside. Therefore, by moving the camera position and the lamp position in the radial direction over the translucent wall 20 at given flow conditions in the pneumatic lines 18, 28, 32, it is possible to use an optimum particle density and particle velocity for the detection and analysis of the image information.
- the particle density can also be adjusted via the positioning of the funnel below the roller passage 6 and / or the size of the funnel opening.
- An adjustment of both the particle density and the particle velocity in the gap 10 can also be done by adjusting the gap distance, ie by adjusting the distance between the walls 20, 22.
- the inventive system thus offers a great freedom in the adjustment of the particle density and the particle velocity, the coarse adjustment mainly by the position of the hopper 8, by the wall distance in the gap 10 and by the amount of false air supply via the opening 38, while the fine adjustment mainly on the throttle valve 34 takes place in the branch line 32.
- Fig. 2 is a block diagram of another part of the system according to the invention for illustrating its means for detecting and processing regrind information.
- the light source 24 is located to the right of the gap 10 and the camera 12 to the left thereof (projection version).
- the translucent walls 20, 22 are not shown here.
- the light source 24 is synchronized with the camera 12 via a timing generator 26 to obtain a stroboscope 24, 26 and a camera whose duty cycle is synchronous with the strobe.
- the camera 12 thus takes still images of the shadow of the Mahlgutp
- the signal output of the camera 12 is connected to a computer 14, on which the image processing and the statistical evaluation of the grinding stock still images are performed (see Fig. 3).
- Fig. 3 shows a part of the detection and processing of the regrind image information.
- the images captured in the camera 12 may be more or less perfect, ie sharp still images.
- the sharpness of a particle image or a particle shadow also depends on the particle velocity. Since there is generally no laminar flow in the gap 10 and is also not necessarily intended (turbulence can act as a deagglomerator), the different regrind particles in the presentation section or in the field of view of the camera 12 sometimes have quite different speeds. So it may happen that some of the particle images are sharp and others are blurred or smeared in the direction of particle velocity.
- a particularly small depth of focus of about 0.2 to 2 mm.
- the raw images of the image sensor of the camera 12 obtained in this way can be further processed.
- the Rohbiider the camera are digitally processed (pixel filter). Initially, an inhomogeneous illumination or brightness in the particle images and in the image background or in the particle shadow is corrected.
- sharp particles or particle images are selected, which are then fed to the further evaluation.
- this selection is representative of the totality of all particle images. If this is not the case, it is possible to work with several cameras 12 in different subareas of the gap 10 and to average the raw images or the sharp particle images or particle shadows selected from them.
- the particles or the particle images or the particle shadows are measured and a volume approximation is performed.
- a typical cereal ground product eg wheat, barley, rye
- the maximum dimension Dmax of a regrind particle and the minimum dimension Dmin of a regrind particle hardly differ by more than a factor of two , ie Dmax ⁇ 2 Dmin.
- V ka 2 b. Since in the present case the particles to be examined have a platelike shape, it is also possible to replace the volume by the projection surface of the particles, ie the third dimension (thickness) is constant and is included in the geometry constant k.
- Fig. 4 shows a specific aspect of the detection and processing of optical millbase information.
- the vertical axis shows the flash intensity L.
- the horizontal axis shows the time t.
- the temporal flash pattern shows a short, intense still-image strobe flash and a slightly later trajectory strobe flash. Since the time interval between two consecutive still-picture strobe flashes can be more than a hundred times or even more than one thousand times the duty cycle of a stroboscopic flash, the time axis is shown interrupted.
- the detection of the particle images or particle shadows can take place by means of a series of stroboscopic flashes comprising a first sub-series of still-image stroboscopic flashes with a first on-time T1 and a first light intensity L1 and a second sub-series of trajectory stroboscopic flashes with a second on-time T2 > 2 T1 and a second light intensity L2 ⁇ L1.
- the switch-off duration T3 between the still-picture stroboscopic flash and the trajectory stroboscopic flash fulfills the relationship 2 D ⁇ v T3 ⁇ 10 D and in particular the relationship 2 D ⁇ v T3 ⁇ 7 D.
- the duty T1 of the still-picture strobe flashes should satisfy the relationship v T1 "D and, in particular, the relationship v T1 ⁇ D / 10.
- the duty T2 of the trajectory strobe flashes should satisfy the relationship v T2> D and in particular the relationship v T2> 5 D.
- the light intensity L1 of the still-picture strobe flashes and the light intensity L2 of the runway strobe flashes are different from each other. This can also be used to distinguish the resulting still images and trajectory images.
- the particle still images, to which a particle trajectory can be assigned can be stored in a first still image memory, so that the respective particle still image information is stored in a still image memory for each completed still image strobe flash and trajectory strobe flash.
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Pathology (AREA)
- Analytical Chemistry (AREA)
- Food Science & Technology (AREA)
- General Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- Immunology (AREA)
- Dispersion Chemistry (AREA)
- Hydrology & Water Resources (AREA)
- Signal Processing (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Sampling And Sample Adjustment (AREA)
- Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/CH2005/000242 WO2006000112A1 (de) | 2004-06-25 | 2005-05-02 | System und verfahren zur mahlgut-charakterisierung in einem walzenstuhl |
PCT/CH2005/000429 WO2006116882A1 (de) | 2005-05-02 | 2005-07-21 | System und verfahren zur partikelstrom-charakterisierung |
Publications (1)
Publication Number | Publication Date |
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EP1877777A1 true EP1877777A1 (de) | 2008-01-16 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05759810A Withdrawn EP1877777A1 (de) | 2005-05-02 | 2005-07-21 | System und verfahren zur partikelstrom-charakterisierung |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP1877777A1 (de) |
CN (1) | CN101171513A (de) |
AU (1) | AU2005331499A1 (de) |
CA (1) | CA2607200A1 (de) |
IL (1) | IL187028A0 (de) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2322911A1 (de) * | 2009-11-13 | 2011-05-18 | Bühler AG | Vorrichtung zum Bestimmen von Partikelgrössen |
CN104749073B (zh) * | 2015-04-02 | 2017-10-10 | 东南大学 | 一种颗粒机械强度的测试装置及方法 |
CN113418845B (zh) * | 2021-06-25 | 2023-02-24 | 山东诺方电子科技有限公司 | 一种尘荷采集设备的维护校准系统及方法 |
CN116510813B (zh) * | 2023-05-16 | 2023-09-19 | 南京巨华工业技术有限公司 | 一种使用管式辊磨机的煤矸石粉磨系统 |
-
2005
- 2005-07-21 CA CA002607200A patent/CA2607200A1/en not_active Abandoned
- 2005-07-21 CN CNA2005800496881A patent/CN101171513A/zh active Pending
- 2005-07-21 AU AU2005331499A patent/AU2005331499A1/en not_active Abandoned
- 2005-07-21 EP EP05759810A patent/EP1877777A1/de not_active Withdrawn
-
2007
- 2007-10-30 IL IL187028A patent/IL187028A0/en unknown
Non-Patent Citations (1)
Title |
---|
See references of WO2006116882A1 * |
Also Published As
Publication number | Publication date |
---|---|
CA2607200A1 (en) | 2006-11-09 |
IL187028A0 (en) | 2008-02-09 |
CN101171513A (zh) | 2008-04-30 |
AU2005331499A1 (en) | 2006-11-09 |
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