NO120634B

NO120634B -

Info

Publication number: NO120634B
Application number: NO170121A
Authority: NO
Inventors: L Allan; G Newbold; A Percival
Original assignee: Fisons Pest Control Ltd
Priority date: 1966-10-15
Filing date: 1967-10-13
Publication date: 1970-11-16
Also published as: BE704877A; DE1670940A1; NL6713923A; BR6793419D0; FR1540740A; ES346060A1; GB1186504A; OA02712A; CH486842A; LU54631A1

Description

Denne oppfinnelse vedrører et vakuumplanfilter. This invention relates to a vacuum plane filter.

Et vakuumplanfilter kan arbeide på den måte at oversiden av en i hovedsaken sirkulær og horisontalt anordnet filterskive tilføres filtrergods, fra hvilket væske fjernes ved vakuum, som tilføres filterskivens underside. Etter avsluttet behand-ling fjernes filtergodset ved hjelp av en avskrapningskniv. A vacuum planar filter can work in such a way that the upper side of an essentially circular and horizontally arranged filter disk is supplied with filter material, from which liquid is removed by vacuum, which is supplied to the underside of the filter disk. After finishing the treatment, the filter material is removed with the help of a scraping knife.

I det tilfelle at filterskiven utføres stasjonær, må tilføringsanordningen for filtreringsgods samt avskrapningskniven anordnes bevegelig i forhold dertil, eksem-pelvis bevegelig om en vertikal og sentralt i forhold til filtreringsskiven anordnet aksel. Derved oppnår man den fordel, at ingen tetningsproblem oppstår ved et stasjonært filter. Imidlertid har bruken av en dreibar avskrapningskniv medført at godset fjernes fra filtreringsflaten langs hele dennes periferi. Dette er ikke ønskelig. In the event that the filter disk is made stationary, the supply device for filtering material and the scraping knife must be arranged movable in relation thereto, for example movable about a vertical and centrally arranged shaft in relation to the filtering disk. This achieves the advantage that no sealing problem occurs with a stationary filter. However, the use of a rotatable scraping knife has meant that the material is removed from the filtering surface along its entire periphery. This is not desirable.

Om tilføringsanordningen for filtreringsgods og avskrapningskniven anordnes stasjonært oppnår man den fordel, at godset fjernes på ett og samme sted, hvor-fra det lett kan videretransporteres, men isåfall må filtreringsskiven anordnes dreibart, og dette medfører ikke ønskelige tetningsproblemer. If the supply device for filtering material and the scraping knife are arranged stationary, the advantage is achieved that the material is removed in one and the same place, from where it can easily be transported on, but in this case the filtering disc must be arranged rotatably, and this does not entail desirable sealing problems.

Foreliggende oppfinnelse har til for-mål å skaffe et vakuumplanfilter, i hvilket fordelene ved de nevnte to filtertypene kombineres. The aim of the present invention is to provide a vacuum planar filter, in which the advantages of the aforementioned two filter types are combined.

Vakuumplanfiltret er av den type som omfatter en i hovedsaken sirkulær og horisontalt anordnet filterskive til hvis overside det gods som skal filtreres tilføres ved hjelp av en spredeanordning som er dreibart anordnet omkring en vinkelrett på filterskiven og sentralt i forhold til denne anordnet aksel, og som er forsynt med en eller flere åpninger som fordeler filtrergodset over et relativt smalt område som strekker seg fra filterskivens sentrale del til dens omkrets, idet en avskrapningskniv er anordnet i fast forbindelse med spredeanordningen i sådant relativt forhold til åpningene eller åpningen at gods som er frafiltrert på filterskiven fjernes ved spredeanordningens rotasjon fra filterflaten umiddelbart før denne påføres nytt filtrergods. The vacuum planar filter is of the type which comprises an essentially circular and horizontally arranged filter disc to whose upper surface the material to be filtered is supplied by means of a spreading device which is rotatably arranged around a perpendicular to the filter disc and centrally in relation to this arranged shaft, and which is provided with one or more openings that distribute the filter material over a relatively narrow area that extends from the central part of the filter disc to its circumference, a scraping knife being arranged in fixed connection with the spreading device in such a relative relationship to the openings or the opening that material that has been filtered out on the filter disc is removed by the spreader's rotation from the filter surface immediately before new filter material is applied to it.

Ifølge oppfinnelsen er avskrapningskniven utformet på en sådan måte at den løfter materialet opp til en i et høyere nivå anordnet avstryker. According to the invention, the scraping knife is designed in such a way that it lifts the material up to a scraper arranged at a higher level.

Andre fordeler ved oppfinnelsen og ytterligere trekk ved denne fremgår av føl-gende detaljerte beskrivelse av en utførel-sesform av vakuumplanfilter under henvis-ning til tegningen. Her viser fig. 1 filtrer-ingsapparatet skjematisk og i vertikalt snitt, fig. 2 en tilsvarende noe forenklet avbildning av det i fig. 1 viste apparat i en annen arbeidsstilling, og fig. 3 viser et horisontalt snitt gjennom filtrets øvre del. På en plan, sirkelrund filterskive 1 spredes filtreringsgodset ved en roterende, radielt rettet spredeåpning 2, koplet til en skrape-kniv 8. Filtreringsgodset tilføres åpningen 2 gjennom en hul, dreibar aksel 3, som sam-tidig er bæreanordning for kniven 8 og et horisontalt plan 10. I passende vinkelav-stand fra kniven 8 og festet til akslen 3 er anordnet et radielt fra akslen gående rør 4, som er lukket i den ene ende. Dette rør er langs hele sin lengde forsynt med små hull og tjener som vaskeanordning for godset. Røret 4 munner inn i en i akslen 3 værende kanal 5, gjennom hvilken vaskevæske utenfra gjennom en stuss 19 kan til-føres vaskeanordningen. Ved et vakuumrør 6 koplet til filtrets hele nedre flate, kan filtreringshastigheten påskynnes således at godset etter en dreining av sprederen på mindre enn 360° er vasket og avsuget og ferdig til å transporteres bort. Vakuumkaret 6 står gjennom et rør 7 i forbindelse med en pumpeanordning som oppretthol-der vakuum i karet 6 og transporterer bort i karet samlet filtrat. Umiddelbart foran spredeanordningen 2 sitter kniven 8 for avskrapning av godset fra filtret og strekker seg radielt over filtret 1. Denne anordning utgjøres av en vinkelbøyet plate formet som en kniv 8 som ved akslens 3 rotasjon beveger seg umiddelbart over filtrets øvre flate og fører det på filtret lig-gende gods opp på et med avskraperen forenet horisontalt sirkelrundt plan 10 som strekker seg ca. 300° fra avskraperens for-kant. Fra dette plan bortføres godset gjennom en åpning 11 (se fig. III). Dette ut-føres ved hjelp av en i det øvre plan frem-og tilbakegående avstryker 12, hvis beve-gelser reguleres av en på akslen 3 anordnet kamskive 13. Other advantages of the invention and further features thereof appear from the following detailed description of an embodiment of a vacuum plane filter with reference to the drawing. Here, fig. 1 the filtering apparatus schematically and in vertical section, fig. 2 a corresponding somewhat simplified representation of that in fig. 1 showed the device in another working position, and fig. 3 shows a horizontal section through the upper part of the filter. On a flat, circular filter disk 1, the filtering material is spread by a rotating, radially directed spreading opening 2, connected to a scraper knife 8. The filtering material is fed to the opening 2 through a hollow, rotatable shaft 3, which is simultaneously a carrying device for the knife 8 and a horizontal plan 10. At a suitable angular distance from the knife 8 and attached to the shaft 3, a tube 4 extending radially from the shaft, which is closed at one end, is arranged. This pipe is provided with small holes along its entire length and serves as a washing device for the goods. The pipe 4 opens into a channel 5 in the shaft 3, through which washing liquid can be supplied to the washing device from the outside through a nozzle 19. With a vacuum tube 6 connected to the entire lower surface of the filter, the filtration speed can be accelerated so that the goods, after a rotation of the spreader of less than 360°, are washed and extracted and ready to be transported away. The vacuum vessel 6 is connected through a pipe 7 to a pump device which maintains a vacuum in the vessel 6 and transports collected filtrate away in the vessel. Immediately in front of the spreading device 2 is the knife 8 for scraping off the material from the filter and extends radially over the filter 1. This device consists of an angled plate shaped like a knife 8 which, when the shaft 3 rotates, moves immediately over the upper surface of the filter and guides it onto the filter lying goods on a horizontal circular plane 10 united with the scraper, which extends approx. 300° from the front edge of the scraper. From this level, the goods are removed through an opening 11 (see fig. III). This is carried out with the help of a wiper 12 moving back and forth in the upper plane, whose movements are regulated by a cam disc 13 arranged on the shaft 3.

I visse tilfelle kan det være forbundet med noen vanskelighet å få godset løst fra filtret. For å lette løsgjøringen befinner der seg under filtret i vakuumkaret en anordning 14, ved hvis hjelp der presses luft gjennom et begrenset område av filter-duken. Ved hjelp av et på en slik måte oppstående lufttrykk bringes godset til å løsne fra filterplaten, slik at kniven lettere kan skrape godset av. Anordningen 14 be-står av en radielt forløpende arm 15 på hvis overside er spent en tynn og delvis med fine hull forsynt membran 16. På mem-branen er omkring hullene festet en ram-me 17 som oventil ligger an mot filtrets underside. Gjennom kanalen 18 kan over-trykk utøves mot membranens underside. Ved membranens utbøyning oppover tryk-kes rammen mot filtrets underside, og den gjennom hullene passerende luft går gjennom filtret og løsgj ør godset fra filtrets øvre flate. Rammen 17 er anordnet mot filtrets underside under og foran den til skrapning av godset tjenende kniv 8, og roterer synkront med denne. Filtret har følgende fordeler: Tilførslen av filtreringsgodset skjer ved fritt fall og dette sammen med en Oscar Andersens In certain cases, it may be associated with some difficulty in getting the goods released from the filter. To facilitate the release, there is a device 14 under the filter in the vacuum vessel, with the help of which air is forced through a limited area of the filter cloth. With the help of an air pressure created in such a way, the material is brought to loosen from the filter plate, so that the knife can more easily scrape the material off. The device 14 consists of a radially extending arm 15 on the upper side of which is stretched a thin membrane 16 partially provided with fine holes. A frame 17 is attached to the membrane around the holes, the top of which rests against the underside of the filter. Through the channel 18, over-pressure can be exerted against the membrane's underside. When the membrane is deflected upwards, the frame is pressed against the filter's underside, and the air passing through the holes passes through the filter and loosens the material from the filter's upper surface. The frame 17 is arranged against the underside of the filter below and in front of the scraping knife 8 serving the goods, and rotates synchronously with it. The filter has the following advantages: The supply of the filtering material occurs by free fall and this together with an Oscar Andersen's

Claims

rotating spreading arm 2 enables an even application on the filter surface. The distribution over the surface can be improved by providing the horizontal part of the knife 8, which acts as a distributor of the filter material, with combs or guide rails. The filter surface is stationary, flat and horizontal, which is the prerequisite for an even distribution of the goods. The filter also has the advantage that the thickness of the filtering material on the filter can be selected solely with regard to what is best for good filtration and primarily for good washing with the least possible amount of washing liquid. Neither of these two advantages is achieved by a rotating drum filter. The filtrate is withdrawn downwards by fixed devices which do not involve any sealing problems. The supply of washing liquid can take place in any angular position in relation to the supply.

1. Vacuum planar filter of the type which comprises an essentially circular and horizontally arranged filter disc (1) to the upper side of which the material to be filtered is supplied by means of a spreading device (2, 8, 9) which is rotatably arranged around a perpendicular to the filter disc ( 1) and centrally in relation to this arranged shaft, and which is provided with one or more openings (2) which distribute the filter material over a relatively narrow area which extends from the central part of the filter disk (1) to its circumference, as a scraping knife (8 , 2) is arranged in fixed connection with the spreading device (2, 8, 9) in such a relative relationship to the openings or the opening (2) that material that has been filtered off on the filter disk is removed by the rotation of the spreading device from the filter surface immediately before it is applied with new filter material, characterized by , that the scraping knife (8, 9) is designed in such a way that it lifts the material up to a scraper (12) arranged at a higher level.

2. Vacuum plane filter according to claim 1, characterized in that a device for flushing with compressed air (15, 16, 17) extends at the underside of the filter disc (1) from its central part to its circumference and is kept in contact with the underside of the filter disc (1) during synchronous rotation with the spreading device (2, 8, 9) in such a way that the air flushing is carried out in the filtering area where scraping takes place.