EP0443119B1 - Dynamic roller mill-air classifier - Google Patents
Dynamic roller mill-air classifier Download PDFInfo
- Publication number
- EP0443119B1 EP0443119B1 EP90122986A EP90122986A EP0443119B1 EP 0443119 B1 EP0443119 B1 EP 0443119B1 EP 90122986 A EP90122986 A EP 90122986A EP 90122986 A EP90122986 A EP 90122986A EP 0443119 B1 EP0443119 B1 EP 0443119B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- classifier
- rotor
- roller mill
- flow
- air classifier
- 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.)
- Expired - Lifetime
Links
- 239000000463 material Substances 0.000 claims abstract description 47
- 230000000630 rising effect Effects 0.000 claims description 4
- 239000011362 coarse particle Substances 0.000 abstract 1
- 230000005484 gravity Effects 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 24
- 239000012159 carrier gas Substances 0.000 description 7
- 230000001174 ascending effect Effects 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 238000013461 design Methods 0.000 description 4
- 230000001413 cellular effect Effects 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000004568 cement Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 239000012876 carrier material Substances 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C23/00—Auxiliary methods or auxiliary devices or accessories specially adapted for crushing or disintegrating not provided for in preceding groups or not specially adapted to apparatus covered by a single preceding group
- B02C23/18—Adding fluid, other than for crushing or disintegrating by fluid energy
- B02C23/24—Passing gas through crushing or disintegrating zone
- B02C23/32—Passing gas through crushing or disintegrating zone with return of oversize material to crushing or disintegrating zone
Definitions
- the invention relates to a dynamic roller mill air flow classifier according to the preamble of claim 1.
- Airflow classifiers of this type which are provided integrated directly above a roller mill, are generally known.
- An approximately comparable air flow classifier is known from "Cement-Lime Gypsum", No. 10/1987, p. 524, Figure 3.
- the flow principle implemented there envisages a gas regrind flow rising in the exterior. In the upper area of the classifier, this is fed radially and tangentially inwards to a centrifugal basket classifier via fixed guide vanes.
- the gas fine material flow is diverted upwards in the centrifugal basket, while semolina and coarse grain are returned downwards to the roller or roller mill via a conical collector.
- this is a reduction in the upward energy of the ground material coming from the upper part of the mill, mainly the fine material, with less dynamic energy.
- the gas regrind flow or the material mass flow that is offered to the classifier in a roller mill essentially depends on the gas speed in the guide vane ring around the grinding table and the direction of the gas flow and the gas speed in the upper part of the mill is.
- the gas regrind flow from the mill room to the classifier is often faced with a part of the coarse material separated from the classifier, which flows downwards from the classifier housing, in counterflow, whereby this counterflow can sometimes reach up to 50%.
- a portion of the finished product portion present in the gas stream at the outlet of the upper mill part with coarse material flowing back is returned to the grinding bowl.
- the actual separator chamber with its annular gap cross section must be designed in such a way that the upward gas velocity also allows the particles pushed against the separator wall to move downwards.
- This can result in a strong sensitivity of the classifier to fluctuations in the gas quantity and thus also an influence on the roller mill run.
- this disadvantageous effect can be referred to as a "bypass fraction", with fine particles which have once been pushed outwards against the classifier wall in a strand of material Have more opportunity to be brought into the actual classifier zone, i.e. near the sight strips.
- bypass fraction probably influences the throughput and the specific work requirements more than the ability of the classifier to produce a steep grain line in the finished product.
- the bypass portion should be eliminated as far as possible.
- a criterion as to how far this can be achieved can be seen in the proportion of finished or fine product that is present in the fluidized bed above the guide vane ring around the grinding table. The aim is therefore to reduce the proportion of fine material in the grinding bed as much as possible, since this inevitably leads to an increase in performance and energy savings when considering the combination of the roller mill classifier.
- the aim is therefore to distribute the regrind fed to the classifier as homogeneously as possible and at a uniform speed over the entire rotor height of the classifier.
- the regrind obtained in a reduction process is fed to a classifier in an ascending gas flow.
- the classifier has an upper, central fine material outlet and a coarse material discharge sloping radially outwards as well as radially and axially adjustable blind devices, by means of which different flow velocities and separations are to be made possible.
- the invention is based on the object, especially design a Roller mill air classifier in relation to the total energy requirement of the system efficiently, the gas flow rates can be reduced in relevant areas.
- An essential feature of an air flow classifier according to the invention with a centrally provided riser pipe for the ascending gas regrind flow can be seen in the fact that the coarse and fine material are discharged from the sighting space separately from the ascending gas regrind flow in external return lines or discharge channels .
- the viewing area between the largely vertical viewing strips and the inner housing wall of the classifier is designed with cone-shaped, ring-like blind segments, which are provided in several stages at the level of the classifying zone.
- These blind segments are moved, for example directly on the inner wall of the classifier housing or attached to the inner wall using spacers.
- the general alignment of these blind rings downwards and inwards means that the gas regrind flow, which falls downwards on an upper blind level between the blind and the inner wall of the classifier housing, is fed inwards again on the lower blind level and thus again fed to the screening process is, so that just fine particles can be classified excellent.
- the fine material particles are guided through the sight strips into the sight basket and down through the bottom opening of the classifier, which surrounds the riser in a ring, wherein a largely horizontal gas discharge channel can be provided in the lower area of the classifier.
- the gas discharge duct expediently has fines collecting channels, as a result of which downstream filters are relieved.
- the coarse material thrown outwards in the classifying chamber by the centrifugal forces is collected approximately in the form of a funnel and led downwards, this being done via external return lines, which are provided approximately in the form of an arc in the lower region of the classifier and suitably return the coarse grain to the actual mill via cellular wheel locks.
- roller mill air flow classifier according to the invention is therefore characterized by a clear separation of the gas and material flows, a multiple supply to the classification process being realized as a downflow classifier with an energy-saving design.
- the carrier gas regrind flowing upwards in the central riser pipe is mushroom-like channeled in the upper area of the classifier housing by a downwardly directed distributor cone and the riser pipe, which widens upwards to the diameter of the rotor, with a somewhat tapering flow channel. It is particularly advantageous if, in the deflection area of this channeling, there are approximately radially directed vanes, for example on the distribution cone, which promote a radial and tangential outflow.
- the actual sight strips of the centrifugal basket or the rotor are suspended around the height of the outflow channel via aerodynamically shaped driver bolts.
- a few such driving bolts are sufficient here, while the viewing strips arranged underneath via an annular disc are designed in accordance with the classification requirements, taking into account the material to be processed and the rotational and gas speeds.
- Air flow classifier with a speed of approx. 12 m / s for cement raw material.
- the cylindrical outlet cross-section in the area of the driving bolts that is to say between the rotor cover disk and the upper ring disk for the viewing strips, can be designed in such a way that a relatively low flow velocity is possible there.
- speeds of 6 m / s to 3 m / s can be set in the area of the actual viewing area.
- the flow in the horizontal exhaust duct can also be kept very low, for example in the range of 5 m / s. As a result, the wear on the material and the pressure loss can be significantly reduced.
- the blind devices provided in the viewing area can be closed rings, but preferably ring segments, the steps of the blind devices lying one below the other being provided radially offset from one another.
- ring segments for feeding the regrind inwards are again attached below the free arch areas of the higher blind level.
- an external material supply can be provided in the upper part of the classifier, the cover plate of the rotor then expediently functioning as a spreading plate.
- the air flow classifier 10 shown in axial section in FIG. 1 is arranged above the mill housing 31, for example a roller mill 30.
- a central riser pipe 1 which starts from the mill housing 31 via a tapering section 33, the carrier gas regrind flow 40 is transported vertically upwards into the classifier head.
- a classifier rotor 5 with a smaller diameter and largely vertical sight strips 51 is present in the classifier housing 14 in the classifier housing 14, on the one hand.
- This classifier rotor 5 is driven via the rotor axis 15 mounted in the upper part 7 of the classifier.
- the closed rotor cover plate 2 is arranged below it, which in the case of an external, upper material inlet 16 acts as a spreading plate 17.
- a cellular wheel sluice 8 can be provided upstream of the material inlet 16. Suspended on the underside of the rotor cover disk 2 is a downwardly directed distributor cone 19. In terms of flow, this distributor cone interacts with the riser pipe extension 21, which begins approximately halfway up the centrifugal basket.
- driver bolts 6 which can also have a circular cross section, are connected in a rotationally fixed manner to the rotor cover disk 2.
- annular disc 3 is attached to which the vertically downwardly extending classifying strips 51 are attached.
- the classifier rotor 5 has a larger diameter than the riser pipe 1, the classifier rotor 5 being open in the bottom area, so that an annular opening 24 is present for the fine material emerging downwards.
- approximately radially oriented vanes 18 are suitably attached to the underside of the rotor cover disk 2 in order to improve the material distribution and to transfer the channeled ascending flow 20 into a rotating movement.
- a relatively low speed can be set in the outlet area 23 or in the deflection area of the ascending gas material flow, which e.g. can be in the range of 5.5 m / s.
- the radially and tangentially deflected carrier gas regrind flows into a falling flow in the classifying chamber 12, which is formed between the inner wall of the classifier housing 14 and the classifying bars 51.
- several steps of blind segments 4 are installed on the wall side in the viewing space 12 with an inclination inward and downward.
- These blind segments 4, which are fastened in the form of a ring or a ring segment to the inner wall of the classifier housing 14, are fastened directly to the inner wall in a preceding stage and, in a subsequent stage, offset to the inner wall via spacers 13.
- the regrind entering the classifying chamber 12 can be fed several times to the actual classifying process.
- Coarse-grained semolina can be guided, for example, on the inner wall through the radial gap to the next stage of the blind segments and are there, however, again fed to the sighting process in the area of the sight strips 51.
- the blind segments 4 therefore bring about an even distribution of the gas flow over the entire rotor height, so that a more efficient sighting is achieved by homogenization and multiple feed lines.
- the inclination of the conical blind segments 4 is required a precise coordination with the other sighting components, such as gas flow, rotation speed, etc., in order to prevent deposits on these blind segments.
- the coarse sizes 42 flow downward from the viewing space 12 into the conical collecting funnel, the coarse material being fed to the actual mill housing 31 and the grinding bowl via arcuate return lines 32 with cellular wheel locks 9 interposed therebetween.
- a part of the coarse size can also be derived directly from the collecting funnel 11.
- the fine material 41 passing through the viewing strips 51 passes downwards via a chute 26 adjoining the bottom opening 24 of the viewing basket 3.
- this exhaust air duct 44 has fines collecting channels 45 in the lower region. Part of the fine material 41 can already collect in these fine material collecting troughs 45 due to the relatively low exhaust gas flow of approximately 5 m / s. As a result, downstream filters are relieved and the entire gas flow is considerably reduced in terms of energy.
- the concept of the air flow classifier 10 according to the invention therefore improves the specific energy requirement per quantity of material carried through, particularly in the case of an integrated design with a roller mill provided underneath, the material flow being reduced due to the low flow velocities.
Landscapes
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Crushing And Grinding (AREA)
- Combined Means For Separation Of Solids (AREA)
- Filtering Of Dispersed Particles In Gases (AREA)
- Rolls And Other Rotary Bodies (AREA)
- Disintegrating Or Milling (AREA)
- Motor Or Generator Cooling System (AREA)
- Compressor (AREA)
- Finger-Pressure Massage (AREA)
Abstract
Description
Die Erfindung betrifft einen dynamischen Wälzmühlen-Luftstromsichter gemäß Oberbegriff des Anspruchs 1.The invention relates to a dynamic roller mill air flow classifier according to the preamble of
Luftstromsichter dieser Art, die direkt über einer Wälzmühle integriert vorgesehen sind, sind allgemein bekannt. Ein etwa vergleichbarer Luftstromsichter ist aus "Zement-Kalk-Gips", Nr. 10/1987, S. 524, Bild 3, bekannt. Das dort realisierte Strömungsprinzip sieht eine im Außenraum aufsteigende Gas-Mahlgut-Strömung vor. Diese wird im oberen Bereich des Sichters nach radial und tangential innen über feststehende Leitschaufeln einem Schleuderkorbsichter zugeführt. Die Gas-Feingut-Strömung wird im Schleuderkorb nach oben abgeleitet, während Grieße und Grobkorn über einen kegelförmigen Sammler nach unten zur Wälz- bzw. Rollenmühle Zurückgeführt werden.Airflow classifiers of this type, which are provided integrated directly above a roller mill, are generally known. An approximately comparable air flow classifier is known from "Cement-Lime Gypsum", No. 10/1987, p. 524, Figure 3. The flow principle implemented there envisages a gas regrind flow rising in the exterior. In the upper area of the classifier, this is fed radially and tangentially inwards to a centrifugal basket classifier via fixed guide vanes. The gas fine material flow is diverted upwards in the centrifugal basket, while semolina and coarse grain are returned downwards to the roller or roller mill via a conical collector.
Bei den Mahl- und Zerkleinerungsvorgängen von Rohmaterialien, z.B. in der Zementindustrie und dort speziell bei der Klinkervermahlung, stellt sich stets die Frage nach einer energiesparenden Aufbereitungstechnik, so daß man bestrebt ist, den spezifischen Energiebedarf in Wälzmühlen zu reduzieren, wobei man im Bereich der Sichtung und der pneumatischen Materialfördernung in Wälzmühlen noch Möglichkeiten sieht, effizienter die Verfahrensabläufe auszulegen. Hierbei ist die Funktion des Sichters ein maßgebendes Kriterium.In the grinding and comminution processes of raw materials, e.g. in the cement industry and there especially in the clinker grinding, there is always the question of an energy-saving processing technology, so that efforts are made to reduce the specific energy requirement in roller mills, in the area of classification and the pneumatic material conveying in roller mills still sees possibilities to design the process sequences more efficiently. Here the function of the sifter is a decisive criterion.
Die Probleme und damit verbundene Nachteile, die sich bei herkömmlichen integrierten Luftstromsichtern bei Wälz- oder Kugelmühlen stellen, können in etwa drei größere Bereiche unterteilt werden.The problems and disadvantages associated with conventional integrated air flow classifiers in roller or ball mills can be divided into roughly three major areas.
Einmal ist dies eine Reduzierung der Aufwärtsenergie des aus dem Mühlenoberteil kommenden Mahlgutes, hauptsächlich des Feingutes, mit geringerer dynamischer Energie. In dieser Hinsicht muß man sich vergegenwärtigen, daß der Gas-Mahlgut-Strom bzw. der Materialmassenstrom, der dem Sichter in einer Wälzmühle angeboten wird, im wesentlichen abhängig von der Gasgeschwindigkeit im Leitschaufelkranz um den Mahlteller sowie der Richtung des Gasstroms und der Gasgeschwindigkeit im Mühlenoberteil ist.
So wird häufig noch die aus dem Mühlenraum aufsteigende Gas-Mahlgut-Strömung zum Sichter mit einem Teil des vom Sichter abgeschiedenen Grobgutes, welches vom Sichtergehäuse nach unten strömt, im Gegenstrom konfrontiert, wobei diese Gegenströmung teilweise bis zu 50% erreichen kann. Hierdurch wird ein Teil des am Ausgang des Mühlenoberteils im Gasstrom vorhandenen Fertiggutanteils mit zurückfließendem Grobgut nochmals auf die Mahlschüssel zurückgeführt.Firstly, this is a reduction in the upward energy of the ground material coming from the upper part of the mill, mainly the fine material, with less dynamic energy. In this regard, it must be remembered that the gas regrind flow or the material mass flow that is offered to the classifier in a roller mill essentially depends on the gas speed in the guide vane ring around the grinding table and the direction of the gas flow and the gas speed in the upper part of the mill is.
For example, the gas regrind flow from the mill room to the classifier is often faced with a part of the coarse material separated from the classifier, which flows downwards from the classifier housing, in counterflow, whereby this counterflow can sometimes reach up to 50%. As a result, a portion of the finished product portion present in the gas stream at the outlet of the upper mill part with coarse material flowing back is returned to the grinding bowl.
Zum anderen ist der eigentliche Sichterraum mit seinem Ringspaltquerschnitt so auszulegen, daß die aufwärts gerichtete Gasgeschwindigkeit auch eine Abwärtsbewegung der an die Sichterwand abgedrängten Partikel zuläßt. Hieraus kann eine starke Empfindlichkeit des Sichters gegen Gasmengenschwankungen und damit auch eine Beeinflussung des Wälzmühlenlaufs resultieren. Mit anderen Worten kann dieser nachteilige Effekt als "Bypass-Anteil" bezeichnet werden, wobei Feingutpartikel, die einmal in einer Materialsträhne nach außen gegen die Sichterwand abgedrängt worden sind, keine Möglichkeit mehr haben, in die eigentliche Sichterzone, also in die Nähe der Sichtleisten herangeführt zu werden.On the other hand, the actual separator chamber with its annular gap cross section must be designed in such a way that the upward gas velocity also allows the particles pushed against the separator wall to move downwards. This can result in a strong sensitivity of the classifier to fluctuations in the gas quantity and thus also an influence on the roller mill run. In other words, this disadvantageous effect can be referred to as a "bypass fraction", with fine particles which have once been pushed outwards against the classifier wall in a strand of material Have more opportunity to be brought into the actual classifier zone, i.e. near the sight strips.
Dieser sogenannte "Bypass-Anteil" beeinflußt in einer Wälzmühle wahrscheinlich die Durchsatzleistung und den spezifischen Arbeitsbedarf stärker als die Fähigkeit des Sichters, im Fertigprodukt eine steile Kornaufbaulinie zu erzeugen. Der Bypass-Anteil sollte dabei möglichst eliminiert werden. Ein Kriterium, wie weit dies gelingt, kann in dem Anteil an Fertig- bzw. Feingutprodukt gesehen werden, das im Wirbelbett oberhalb des Leitschaufelkranzes um den Mahlteller vorhanden ist. Es wird daher angestrebt, den Anteil an Feingut im Mahlbett soweit wie möglich zu reduzieren, da dies zwangsläufig eine Leistungssteigerung und Energieeinsparung bei der Gesamtbetrachtung der Wälzmühlen-Sichterkombination mit sich bringt.In a roller mill, this so-called "bypass fraction" probably influences the throughput and the specific work requirements more than the ability of the classifier to produce a steep grain line in the finished product. The bypass portion should be eliminated as far as possible. A criterion as to how far this can be achieved can be seen in the proportion of finished or fine product that is present in the fluidized bed above the guide vane ring around the grinding table. The aim is therefore to reduce the proportion of fine material in the grinding bed as much as possible, since this inevitably leads to an increase in performance and energy savings when considering the combination of the roller mill classifier.
Neben diesen beiden vorgenannten negativen Aspekten ist man bestrebt, eine möglichst gleichmäßige Materialzufuhr und Materialverteilung im Sichtraum erzeugen zu können. Hier kann man immer wieder feststellen, daß die Materialbeaufschlagung des Sichterrotors in Wälzmühlen strähnenhaft und ungleichmäßig über die Rotorhöhe verteilt ist, so daß damit eine starke Abhängigkeit von der Strömungsgeschwindigkeit des Trägergases besteht.In addition to these two negative aspects mentioned above, efforts are made to be able to produce a material supply and material distribution in the viewing area that is as uniform as possible. Here you can always see that the material impingement of the classifier rotor in roller mills is streaky and unevenly distributed over the rotor height, so that there is a strong dependence on the flow rate of the carrier gas.
Es wird daher angestrebt, das dem Sichter zugeführte Mahlgut möglichst homogen und mit gleichmäßiger Geschwindigkeit über die gesamte Rotorhöhe des Sichters zu verteilen.The aim is therefore to distribute the regrind fed to the classifier as homogeneously as possible and at a uniform speed over the entire rotor height of the classifier.
Bei einem aus der GB-PS 372 600 bekannten zweistufigen Sichter wird das in einem nicht beschriebenen Verkleinerungsprozeß anfallende Mahlgut in einer aufsteigenden Gasströmung einer Sichtung zugeführt. Der Sichter weist einen oberen, zentralen Feingutauslaß und einen nach radial außen abfallenden Grobgutaustrag sowie radial und axial verstellbare Jalousieeinrichtungen auf, durch welche unterschiedliche Strömungsgeschwindigkeiten und Trennungen ermöglicht werden sollen.In a two-stage classifier known from GB-PS 372 600, the regrind obtained in a reduction process, not described, is fed to a classifier in an ascending gas flow. The classifier has an upper, central fine material outlet and a coarse material discharge sloping radially outwards as well as radially and axially adjustable blind devices, by means of which different flow velocities and separations are to be made possible.
Der Erfindung liegt die Aufgabe zugrunde, einen Wälzmühlen-Luftstromsichter im Hinblick auf den gesamten Energiebedarf der Anlage besonders effizient auszulegen, wobei die Gasströmungsgeschwindigkeiten in maßgebenden Bereichen reduziert werden können.The invention is based on the object, especially design a Roller mill air classifier in relation to the total energy requirement of the system efficiently, the gas flow rates can be reduced in relevant areas.
Diese Aufgabe wird erfindungsgemäß bei einem Wälzmühlen-Luftstromsichter der genannten Art durch die Merkmale des kennzeichnenden Teils des Anspruchs 1 gelöst.This object is achieved in a roller mill air flow classifier of the type mentioned by the features of the characterizing part of
Ein wesentliches Merkmal eines erfindungsgemäßen Luftstromsichters mit einem zentral vorgesehenen Steigrohr für die aufsteigende Gas-Mahlgut-Strömung kann darin gesehen werden, daß das Grob- und Feingut getrennt von der aufsteigenden Gas-Mahlgut-Strömung in außenliegenden Rückführleitungen bzw. Ableitungskanälen aus dem Sichtraum ausgeleitet werden. Hinzu tritt der energiesparende Effekt einer Umlenkung der Trägergas-Mahlgut-Strömung im oberen Bereich des Sichters in eine Fallströmung, wodurch die normalerweise für ein Absaugen der Feingutpartikeln nach oben erforderliche Energie nicht mehr aufgebracht werden muß. Darüber hinaus ist der Sichtraum zwischen den weitgehend vertikalen Sichtleisten und der inneren Gehäusewand des Sichters mit konusförmigen, ringartigen Jalousiesegmenten ausgelegt, die mehrstufig in der Höhe der Sichterzone vorgesehen sind. Diese Jalousiesegmente werden versetzt, z.B. direkt an der Innenwand des Sichtergehäuses oder über Abstandshalter an der Innenwand angebracht. Die generelle Ausrichtung dieser Jalousieringe nach unten und innen bewirkt, daß die Gas-Mahlgut-Strömung, die auf einer oberen Jalousiestufe zwischen der Jalousie und der Innenwand des Sichtergehäuses nach unten fällt, auf der darunter liegenden Jalousiestufe erneut nach innen und damit erneut dem Sichtungsprozeß zugeführt wird, so daß gerade Feingutpartikel hervorragend klassiert werden können. Die Feingutpartikel werden durch die Sichtleisten in den Sichtkorb hinein und über die das Steigrohr ringförmig umgebende Bodenöffnung des Sichters nach unten geführt, wobei im unteren Bereich des Sichters ein weitgehend horizontaler Gasableitungskanal vorgesehen sein kann. Zweckmäßigerweise weist der Gasableitungskanal Feingut-Sammelrinnen auf, wodurch nachgeschaltete Filter entlastet werden.An essential feature of an air flow classifier according to the invention with a centrally provided riser pipe for the ascending gas regrind flow can be seen in the fact that the coarse and fine material are discharged from the sighting space separately from the ascending gas regrind flow in external return lines or discharge channels . In addition, there is the energy-saving effect of deflecting the carrier gas regrind flow in the upper region of the classifier into a downward flow, as a result of which the energy normally required for suctioning the fine material particles upward no longer has to be applied. In addition, the viewing area between the largely vertical viewing strips and the inner housing wall of the classifier is designed with cone-shaped, ring-like blind segments, which are provided in several stages at the level of the classifying zone. These blind segments are moved, for example directly on the inner wall of the classifier housing or attached to the inner wall using spacers. The general alignment of these blind rings downwards and inwards means that the gas regrind flow, which falls downwards on an upper blind level between the blind and the inner wall of the classifier housing, is fed inwards again on the lower blind level and thus again fed to the screening process is, so that just fine particles can be classified excellent. The fine material particles are guided through the sight strips into the sight basket and down through the bottom opening of the classifier, which surrounds the riser in a ring, wherein a largely horizontal gas discharge channel can be provided in the lower area of the classifier. The gas discharge duct expediently has fines collecting channels, as a result of which downstream filters are relieved.
Das durch die Zentrifugalkräfte nach außen im Sichtraum geschleuderte Grobgut wird etwa trichterförmig gesammelt und nach unten geführt, wobei dies über externe Rückführleitungen geschieht, die etwa bogenförmig im unteren Bereich des Sichters vorgesehen sind und geeigneterweise über Zellradschleusen das Grobkorn in die eigentliche Mühle zurückführen.The coarse material thrown outwards in the classifying chamber by the centrifugal forces is collected approximately in the form of a funnel and led downwards, this being done via external return lines, which are provided approximately in the form of an arc in the lower region of the classifier and suitably return the coarse grain to the actual mill via cellular wheel locks.
Das Konzept des erfindungsgemäßen Wälzmühlen-Luftstromsichters zeichnet sich daher durch eine klare Trennung der Gas- und Materialströme aus, wobei eine Mehrfach-Zuführung zum Klassierungsprozeß bei energiesparender Auslegung als Fallstromsichter realisiert ist.The concept of the roller mill air flow classifier according to the invention is therefore characterized by a clear separation of the gas and material flows, a multiple supply to the classification process being realized as a downflow classifier with an energy-saving design.
Die im zentralen Steigrohr nach oben geführte Trägergas-Mahlgut-Strömung wird im oberen Bereich des Sichtergehäuses durch einen nach unten gerichteten Verteilerkegel und das sich nach oben auf den Durchmesser des Rotors etwa erweiterende Steigrohr mit sich etwas verjüngendem Strömungskanal pilzartig kanalisiert. Besonders vorteilhaft ist es, wenn im Umlenkungsbereich dieser Kanalisierung etwa radial gerichtete Flügel etwa am Verteilungskonus vorhanden sind, die eine radial und tangentiale Ausströmung fördern.The carrier gas regrind flowing upwards in the central riser pipe is mushroom-like channeled in the upper area of the classifier housing by a downwardly directed distributor cone and the riser pipe, which widens upwards to the diameter of the rotor, with a somewhat tapering flow channel. It is particularly advantageous if, in the deflection area of this channeling, there are approximately radially directed vanes, for example on the distribution cone, which promote a radial and tangential outflow.
Die eigentlichen Sichtleisten des Schleuderkorbs bzw. des Rotors sind um die Höhe des Ausströmungskanals über aerodynamisch geformte Mitnehmerbolzen abgehängt. Hierbei genügen einige wenige derartiger Mitnehmerbolzen, während die darunter über eine Ringscheibe angeordneten Sichtleisten entsprechend den Klassierungserfordernissen unter Berücksichtigung des zu verarbeitenden Materials und der Rotations- und Gasgeschwindigkeiten ausgelegt sind.The actual sight strips of the centrifugal basket or the rotor are suspended around the height of the outflow channel via aerodynamically shaped driver bolts. A few such driving bolts are sufficient here, while the viewing strips arranged underneath via an annular disc are designed in accordance with the classification requirements, taking into account the material to be processed and the rotational and gas speeds.
Im Hinblick auf die erforderlichen Strömungsgeschwindigkeiten kommt man beispielsweise beim erfindungsgemäßen Luftstromsichter mit einer Geschwindigkeit von ca. 12 m/s bei Zementrohmaterial aus. Der zylinderförmige Austrittsquerschnitt im Bereich der Mitnehmerbolzen, also zwischen Rotordeckscheibe und oberer Ringscheibe für die Sichtleisten, kann so ausgelegt sein, daß eine relativ niedrige Strömungsgeschwindigkeit dort möglich ist. Beispielsweise können im Bereich des eigentlichen Sichtraums Geschwindigkeiten von 6 m/s bis 3 m/s eingestellt werden. Da das Feingut nach unten ausgeleitet wird, kann auch die Strömung im horizontalen Abgaskanal sehr niedrig, z.B. im Bereich von 5 m/s gehalten werden. Hierdurch läßt sich der Verschleiß am Material und der Druckverlust erheblich herabsetzen.With regard to the required flow velocities, one comes, for example, with the invention Air flow classifier with a speed of approx. 12 m / s for cement raw material. The cylindrical outlet cross-section in the area of the driving bolts, that is to say between the rotor cover disk and the upper ring disk for the viewing strips, can be designed in such a way that a relatively low flow velocity is possible there. For example, speeds of 6 m / s to 3 m / s can be set in the area of the actual viewing area. Since the fine material is discharged downwards, the flow in the horizontal exhaust duct can also be kept very low, for example in the range of 5 m / s. As a result, the wear on the material and the pressure loss can be significantly reduced.
Die im Sichtraum vorgesehenen Jalousieeinrichtungen können geschlossene Ringe, bevorzugterweise aber Ringsegmente sein, wobei untereinander liegende Stufen der Jalousieeinrichtungen radial gegeneinander versetzt vorgesehen sind. Geeigneterweise sind unterhalb von freibleibenden Bogenbereichen der höheren Jalousiestufe erneut Ringsegmente für die Zuführung des Mahlgutes nach innen angebracht.The blind devices provided in the viewing area can be closed rings, but preferably ring segments, the steps of the blind devices lying one below the other being provided radially offset from one another. Suitably, ring segments for feeding the regrind inwards are again attached below the free arch areas of the higher blind level.
Für die Vermahlung von Materialien mit hohem Feingutanteil oder bei feinen Zusatzkomponenten kann im Oberteil des Sichters eine externe Materialzufuhr vorgesehen werden, wobei dann zweckmäßigerweise die Deckscheibe des Rotors als Streuteller fungiert.For the grinding of materials with a high proportion of fine material or with fine additional components, an external material supply can be provided in the upper part of the classifier, the cover plate of the rotor then expediently functioning as a spreading plate.
Die Erfindung wird nachstehend anhand eines schematischen Ausführungsbeispiels noch näher erläutert. Es zeigen:
- Fig. 1
- einen axialen Schnitt durch ein Sichtergehäuse, wobei die Trägergas- und Materialströmungen mit Pfeilen dargestellt sind und das eigentliche Mühlengehäuse im unteren Bereich nur schematisch angedeutet ist, und
- Fig. 2
- eine Ansicht des Sichtergehäuses nach Fig. 1 von links in Pfeilrichtung II.
- Fig. 1
- an axial section through a classifier housing, the carrier gas and material flows are shown with arrows and the actual mill housing is only indicated schematically in the lower region, and
- Fig. 2
- a view of the classifier housing of FIG. 1 from the left in the direction of arrow II.
Der in Fig. 1 im Axialschnitt dargestellte Luftstromsichter 10 ist über dem Mühlengehäuse 31 beispielsweise einer Wälzmühle 30 angeordnet. In einem zentralen Steigrohr 1 das über einen Verjüngungsabschnitt 33 vom Mühlengehäuse 31 ausgeht, wird die Trägergas-Mahlgut-Strömung 40 senkrecht nach oben in den Sichterkopf transportiert. Im Sichtergehäuse 14 ist einerseits ein durchmesserkleinerer Sichterrotor 5 mit weitgehend vertikalen Sichtleisten 51 vorhanden. Dieser Sichterrotor 5 wird über die im Oberteil 7 des Sichters gelagerte Rotorachse 15 angetrieben. Mit relativ geringem Abstand zum Oberteil 7 des Sichters ist darunter die geschlossene Rotor-Deckscheibe 2 angeordnet, die im Falle eines externen, oberen Materialeinlasses 16 als Streuteller 17 fungiert. Dem Materialeinlaß 16 vorgeschaltet kann eine Zellradschleuse 8 vorgesehen sein. Abgehängt an der Unterseite der Rotor-Deckscheibe 2 ist ein nach unten gerichteter Verteilerkegel 19. Strömungstechnisch wirkt dieser Verteilerkegel mit der Steigrohrerweiterung 21 zusammen, die etwa auf halber Höhe des Schleuderkorbes beginnt.The
Mit der Rotor-Deckscheibe 2 drehfest in Verbindung stehen einerseits von oben gesehen einige aerodynamisch ausgebildete Mitnehmerbolzen 6, die beispielsweise auch Kreisquerschnitt aufweisen können. Am unteren Ende dieser Mitnehmerbolzen 6 ist eine Ringscheibe 3 angebracht, an der die vertikal nach unten ragenden Sichterleisten 51 befestigt sind.On the one hand, seen from above, some aerodynamically designed driver bolts 6, which can also have a circular cross section, are connected in a rotationally fixed manner to the rotor cover disk 2. At the lower end of this driver pin 6, an annular disc 3 is attached to which the vertically downwardly extending
Der Sichterrotor 5 weist einen größeren Durchmesser als das Steigrohr 1 auf, wobei der Sichterrotor 5 im Bodenbereich offen ausgebildet ist, so daß eine kreisringförmige Öffnung 24 für das nach unten austretende Feingut vorhanden ist.The classifier rotor 5 has a larger diameter than the
Im Bereich des zylinderförmigen Austrittsquerschnitts der aufsteigenden Trägergas-Mahlgut-Strömung 40 sind geeigneterweise etwa radial ausgerichtete Flügel 18 an der Unterseite der Rotor-Deckscheibe 2 befestigt, um die Materialverteilung zu verbessern und die kanalisierte aufsteigende Strömung 20 in eine rotierende Bewegung überzuleiten.In the area of the cylindrical outlet cross section of the ascending carrier
Strömungstechnisch gesehen kann im Austrittsbereich 23 bzw. im Umlenkungsbereich der aufsteigenden Gas-Materialgut-Strömung eine relativ niedrige Geschwindigkeit eingestellt werden, die z.B. im Bereich von 5,5 m/s liegen kann.From a fluidic point of view, a relatively low speed can be set in the
Die radial und tangential umgelenkte Trägergas-Mahlgut-Strömung geht im Sichtraum 12, der zwischen der Innenwand des Sichtergehäuses 14 und den Sichtleisten 51 gebildet ist, in eine Fallströmung über. Um eine möglichst homogene Zuführung über die Sichterhöhe zu erreichen, sind wandseitig im Sichtraum 12 mehrere Stufen von Jalousiesegmenten 4 mit einer Neigungsausrichtung nach innen und abwärts angebracht. Diese ringförmig bzw. ringsegmentförmig an der Innenwand des Sichtergehäuses 14 befestigten Jalousiesegmente 4 sind in einer vorausgehenden Stufe direkt an der Innenwand und in einer nachfolgenden Stufe versetzt über Abstandshalter 13 an der Innenwand befestigt.The radially and tangentially deflected carrier gas regrind flows into a falling flow in the classifying
Auf diese Weise kann das in den Sichtraum 12 eintretende Mahlgut mehrmals dem eigentlichen Sichtprozeß zugeführt werden. Grobkörnige Grieße können dabei beispielsweise an der Innenwand durch den radialen Spalt auf die nächste Stufe der Jalousiesegmente geführt werden und werden jedoch dort erneut dem Sichtprozeß im Bereich der Sichtleisten 51 zugeführt. Die Jalousiesegmente 4 bewirken daher eine gleichmäßige Verteilung des Gasstroms über die gesamte Rotorhöhe, so daß durch Homogenisierung und mehrfache Zuleitung eine effizientere Sichtung erreicht wird. Insbesondere die Neigung der konischen Jalousiesegmente 4 bedarf einer genauen Abstimmung mit den anderen Sichtungskomponenten, wie Gasströmung, Rotationsgeschwindigkeit etc., um eine Anlagerung an diesen Jalousiesegmenten zu verhindern.In this way, the regrind entering the classifying
Die Grobgrieße 42 fließen aus dem Sichtraum 12 nach unten in den konischen Sammeltrichter, wobei das Grobgut über bogenförmig geführte Rückführleitungen 32 mit dazwischen geschalteten Zellradschleusen 9 dem eigentlichen Mühlengehäuse 31 und der Mahlschüssel zugeführt werden. Ein Teil der Grobgrieße kann auch direkt aus dem Sammeltrichter 11 abgeleitet werden.The coarse sizes 42 flow downward from the
Das durch die Sichtleisten 51 hindurchtretende Feingut 41 gelangt über einen sich an die Bodenöffnung 24 des Sichtkorbes 3 anschließenden Fallschacht 26 nach unten. Das Außengehäuse 27 des Fallschachtes 26, das das zentrale Steigrohr mit radialem Abstand umgibt, geht im Beispiel oberhalb des Mühlengehäuses 31 in einen horizontalen Abluftkanal 44 über.The
Wie deutlicher in Fig. 2 zum Ausdruck kommt, weist dieser Abluftkanal 44 im unteren Bereich Feingut-Sammelrinnen 45 auf. In diesen Feingut-Sammelrinnen 45 kann sich bereits ein Teil des Feingutes 41 aufgrund der relativ geringen Abgasströmung von ca. 5 m/s ansammeln. Hierdurch werden sowohl nachgeschaltete Filter entlastet als auch die gesamte Gasströmung energetisch erheblich herabgesetzt.As is more clearly expressed in FIG. 2, this
Das erfindungsgemäße Konzept des Luftstromsichters 10 verbessert daher gerade bei integrierter Ausführung mit einer darunter vorgesehenen Wälzmühle den spezifischen Energiebedarf pro durchgesetzter Materialgutmenge, wobei aufgrund der niedrigen Strömungsgeschwindigkeiten auch eine Reduzierung des Materialverschleisses herbeigeführt werden kann.The concept of the
Claims (9)
- Dynamic roller mill air classifier with an integrated air classifier for a rising gas-grinding material flow located above the roller mill,
with a central riser for the rising gas-grinding material flow and which is tapered with respect to the mill casing, said flow being deflectable radially outwards into a downflow in the upper area of a classifier rotor having roughly vertical classifying ledges, and
with a gas flow outlet and a fine material outlet, which from the flow standpoint follow the classifier rotor, as well as at least one coarse material return,
characterized in that
louvres (4) are provided in the classifier chamber (12) which are directed towards the classifier rotor (5), the gas-fine material flow (41) passing through the classifier rotor (5) from the outside to the inside is led off downwards through a bottom opening (24) of the classifier rotor (5) surrounding the central riser (1) into a drop shaft (27) provided round the riser (1), and
the coarse material (42) from the classifier chamber (12) is returned downwards to the mill casing (31) by means of return lines (32) provided separately with respect to the riser (1). - Roller mill air classifier according to claim 1,
characterized in that
the classifier rotor (5) has a downwardly directed distributing cone (2) for the outwardly directed channelling of the rising gas-grinding material flow (40). - Roller mill air classifier according to claim 1 or 2,
characterized in that
the louvres (4) provided in the annular-cylindrical classifier chamber (12) are constructed as downwardly and inwardly sloping multistage ring segments, which are spaced radially from the classifier casing (14) with alternating stages. - Roller mill air classifier according to one of the claims 1 to 3,
characterized in that
the drop shaft (27) passes into an approximately horizontal spent air duct (44) with preseparating chambers (45) in the lower region for fine material. - Roller mill air classifier according to one of the claims 1 to 4,
characterized in that
the classifier rotor cover disk (2) is constructed as a whizzer. - Roller mill air classifier according to one of the claims 1 to 5,
characterized in that
in the upper part (7) of the classifier is provided an external material inlet (16). - Roller mill air classifier according to one of the claims 1 to 6,
characterized in that
the vertical classifying ledges (51) are provided in spaced manner around the height of the deflecting channel (52) below the rotor cover disk (2). - Roller mill air classifier according to claim 7,
characterized in that
the classifying ledges (51) are connected to the rotor cover disk (2) via a ring disk (3) and several aero-dynamically shaped driving pins (6) located in the deflecting channel (52). - Roller mill air classifier according to one of the claims 3 to 8,
characterized in that
the louvres (4) are adjustable in their inclination angles and/or in their radial spacing with respect to the classifier casing (14).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4005031 | 1990-02-19 | ||
| DE4005031A DE4005031C1 (en) | 1990-02-19 | 1990-02-19 | Dynamic wind sifter for roller mill - has central, restricted riser for air material mixt. flow with downwards deflection in top region of sifter rotor |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0443119A2 EP0443119A2 (en) | 1991-08-28 |
| EP0443119A3 EP0443119A3 (en) | 1992-02-26 |
| EP0443119B1 true EP0443119B1 (en) | 1994-06-15 |
Family
ID=6400403
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP90122986A Expired - Lifetime EP0443119B1 (en) | 1990-02-19 | 1990-11-30 | Dynamic roller mill-air classifier |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US5115989A (en) |
| EP (1) | EP0443119B1 (en) |
| JP (1) | JPH07106341B2 (en) |
| AT (1) | ATE107193T1 (en) |
| CA (1) | CA2036510C (en) |
| DE (2) | DE4005031C1 (en) |
| DK (1) | DK0443119T3 (en) |
| ES (1) | ES2056350T3 (en) |
| LT (1) | LT3222B (en) |
| LV (1) | LV10402B (en) |
| RU (1) | RU2014891C1 (en) |
| UA (1) | UA11094A (en) |
| ZA (1) | ZA911125B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5547133A (en) * | 1993-12-23 | 1996-08-20 | Rogers; Lynn | Manufacture process for ground oat cereal |
| US6260708B1 (en) * | 1996-10-18 | 2001-07-17 | Hosokawa Alpine Aktiengesellschaft | Method for air classification of toner |
| DE102008038776B4 (en) | 2008-08-12 | 2016-07-07 | Loesche Gmbh | Process for the screening of a millbase fluid mixture and mill classifier |
| PE20210292A1 (en) | 2017-12-04 | 2021-02-12 | Goldcorp Inc | LOW ENERGY PROCESS FOR THE EXTRACTION OF METALS |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1623040A (en) * | 1927-04-05 | Method and apparatus for grading solid materials | ||
| US1806980A (en) * | 1931-05-26 | Ptjlvebizeb | ||
| CH1557A (en) * | 1889-09-27 | 1890-02-14 | Mumford Thomas William Basset | Improved apparatus for cleaning dust or other mechanical impurities from the air |
| US857988A (en) * | 1906-07-28 | 1907-06-25 | James W Fuller Jr | Air-separator for pulverizing and grinding mills. |
| GB372600A (en) * | 1930-06-23 | 1932-05-12 | Clarke Chapman Ltd | Improvements in pneumatic apparatus for the separation and grading of solid pulverulent material |
| US2909330A (en) * | 1954-09-30 | 1959-10-20 | Hardinge Harlowe | Pulverizing mill and process of pulverizing material |
| US3090487A (en) * | 1962-04-05 | 1963-05-21 | Sturtevant Mill Co | Method and apparatus for sizing solid particles |
| US3306443A (en) * | 1964-02-19 | 1967-02-28 | Sturtevant Mill Co | Vacuum aspirator mechanism with conical barrier element |
| DE3202054A1 (en) * | 1982-01-23 | 1983-08-04 | Steag Ag, 4300 Essen | CARBON MILLING SYSTEM WITH SPRINKLE RETURN AND SEPARATION FROM PYRITE AND MOUNTAINS |
-
1990
- 1990-02-19 DE DE4005031A patent/DE4005031C1/en not_active Expired - Lifetime
- 1990-11-30 EP EP90122986A patent/EP0443119B1/en not_active Expired - Lifetime
- 1990-11-30 AT AT90122986T patent/ATE107193T1/en not_active IP Right Cessation
- 1990-11-30 ES ES90122986T patent/ES2056350T3/en not_active Expired - Lifetime
- 1990-11-30 DE DE59006151T patent/DE59006151D1/en not_active Expired - Fee Related
- 1990-11-30 DK DK90122986.4T patent/DK0443119T3/en active
-
1991
- 1991-02-15 ZA ZA911125A patent/ZA911125B/en unknown
- 1991-02-18 CA CA002036510A patent/CA2036510C/en not_active Expired - Fee Related
- 1991-02-18 UA UA4894499A patent/UA11094A/en unknown
- 1991-02-18 RU SU914894499A patent/RU2014891C1/en active
- 1991-02-19 JP JP3024847A patent/JPH07106341B2/en not_active Expired - Lifetime
- 1991-02-19 US US07/656,549 patent/US5115989A/en not_active Expired - Fee Related
-
1992
- 1992-12-30 LV LVP-92-562A patent/LV10402B/en unknown
-
1993
- 1993-03-19 LT LTIP433A patent/LT3222B/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| US5115989A (en) | 1992-05-26 |
| ES2056350T3 (en) | 1994-10-01 |
| JPH07106341B2 (en) | 1995-11-15 |
| LV10402B (en) | 1995-04-20 |
| DK0443119T3 (en) | 1994-10-24 |
| EP0443119A2 (en) | 1991-08-28 |
| EP0443119A3 (en) | 1992-02-26 |
| JPH06206050A (en) | 1994-07-26 |
| LT3222B (en) | 1995-04-25 |
| DE59006151D1 (en) | 1994-07-21 |
| LV10402A (en) | 1995-02-20 |
| DE4005031C1 (en) | 1991-08-08 |
| ZA911125B (en) | 1991-11-27 |
| CA2036510C (en) | 1997-05-06 |
| ATE107193T1 (en) | 1994-07-15 |
| LTIP433A (en) | 1994-10-25 |
| UA11094A (en) | 1996-12-25 |
| RU2014891C1 (en) | 1994-06-30 |
| CA2036510A1 (en) | 1991-08-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE102008038776B4 (en) | Process for the screening of a millbase fluid mixture and mill classifier | |
| DE3621221C2 (en) | ||
| EP0325770B1 (en) | Grinding method and arrangement | |
| EP2106301B1 (en) | Classifying device for classifying granular material and circulating grinding plant incorporating such a classifying device | |
| EP1948360B1 (en) | Roller mill | |
| DE3508889C1 (en) | Air classifier with wear-free classifying wheel | |
| EP0250921B1 (en) | Air classifier | |
| WO1992003227A1 (en) | Device for crushing and sorting loose materials | |
| AT401741B (en) | WINDSIGHTER | |
| DE1782775A1 (en) | Rotary air separator | |
| DE3222878C1 (en) | Method for operating an air classifier and wind classifier for carrying out the method | |
| DE894803C (en) | Device and method for air classification | |
| EP0443119B1 (en) | Dynamic roller mill-air classifier | |
| DE1757582C2 (en) | Centrifugal basket wind sifter | |
| EP0377826B1 (en) | Sifter | |
| EP0492062B1 (en) | Air separator | |
| DE9015363U1 (en) | Device for material dispersion | |
| DE4014342C2 (en) | Air classifier | |
| DE102014001384B4 (en) | Ring-shaped cascade classifier with downstream rod basket sifter | |
| DE3229629C2 (en) | ||
| EP0641609B1 (en) | Wind sifter | |
| DE1607536A1 (en) | Blinds viewer | |
| DE3741650C1 (en) | Apparatus for classifying dust-like bulk materials | |
| DE4132339C2 (en) | Turbo centrifugal classifier | |
| DE9017176U1 (en) | Wind sifter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT CH DE DK ES FR GB IT LI |
|
| PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
| AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT CH DE DK ES FR GB IT LI |
|
| 17P | Request for examination filed |
Effective date: 19920507 |
|
| 17Q | First examination report despatched |
Effective date: 19930312 |
|
| RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: LOESCHE GMBH |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT CH DE DK ES FR GB IT LI |
|
| REF | Corresponds to: |
Ref document number: 107193 Country of ref document: AT Date of ref document: 19940715 Kind code of ref document: T |
|
| ET | Fr: translation filed | ||
| REF | Corresponds to: |
Ref document number: 59006151 Country of ref document: DE Date of ref document: 19940721 |
|
| GBT | Gb: translation of ep patent filed (gb section 77(6)(a)/1977) |
Effective date: 19940720 |
|
| ITF | It: translation for a ep patent filed | ||
| REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2056350 Country of ref document: ES Kind code of ref document: T3 |
|
| REG | Reference to a national code |
Ref country code: DK Ref legal event code: T3 |
|
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19960927 Year of fee payment: 7 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 19961010 Year of fee payment: 7 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19961101 Year of fee payment: 7 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 19961118 Year of fee payment: 7 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19961121 Year of fee payment: 7 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19971130 Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19971130 Ref country code: FR Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19971130 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19971130 Ref country code: AT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19971130 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19971201 |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19971130 |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DK Payment date: 19981116 Year of fee payment: 9 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19981130 Year of fee payment: 9 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DK Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19991130 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20000901 |
|
| REG | Reference to a national code |
Ref country code: DK Ref legal event code: EBP |
|
| REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 19981212 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20051130 |