DK159643B

DK159643B - granulation

Info

Publication number: DK159643B
Application number: DK335888A
Authority: DK
Inventors: Peter Lip
Original assignee: Smidth & Co As F L
Priority date: 1988-06-20
Filing date: 1988-06-20
Publication date: 1990-11-12
Also published as: DK335888D0; WO1989012497A1; PT90917A; DK159643C; ES2016142A6; PT90917B; DK335888A

Description

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DK 159643 BDK 159643 B

Opfindelsen angår en fremgangsmåde af den i krav l's indledning angivne art. Kendte granuleringsmetoder under anvendelse af rotationstallerkener eller snegletransportører er behæftet med forskellige ulemper, dels i form 5 af høje omkostninger, dels i form af mangler ved det frembragte granulat såsom for stor størrelse eller lagdelt struktur, der kan medføre tendens til smuldring eller forvitring.The invention relates to a method of the kind set out in the preamble of claim 1. Known methods of granulation using rotary plates or auger conveyors suffer from various disadvantages, partly in the form of high costs, partly in the form of deficiencies in the granules produced, such as excessive size or layered structure, which may cause a tendency to crumble or weathering.

Der kendes fremgangsmåder til granulering, hvor der 10 anvendes enten rotationstallerkener eller et snegle- transportørsystem (et kollergangs-princip). Disse kendte fremgangsmåder har flere ulemper, og hvad således angår rotationstallerken-princippet, medfører dette almindeligvis dyre anlæg, og hvor granuleringsmetoden desuden 15 har vist sig uhensigtsmæssig derved, at selve granulaterne får en lagdelt struktur, som gør, at granulaterne har tendens til at skille eller forvitre, når de tørres ved høje temperaturer.Methods of granulation are known, using either rotary plates or a auger conveyor system (a chute principle). These known methods have several drawbacks, and thus with regard to the rotation plate principle, this usually entails expensive plants, and where the granulation method has also been found to be inconvenient in that the granules themselves have a layered structure which causes the granules to tend to separate. or weathering when dried at high temperatures.

Ved kollergangsprincippet bliver råmaterialet under-20 kastet en befugtning gennem en snegletransportør, en formaling på en fugterkollergang og passerer typisk en rystesigte eller, via et såkaldt "kødhakkemaskine"-princip, gennem en hertil indrettet hulforsynet plade, hvorved det æltede materiale føres ud i et antal baner 25 og hakkes af i passende længder. Denne fremstillingspro ces indebærer ligeledes forholdsvis store omkostninger, hvor der her desuden kræves en omfattende for- og efterbehandling af råmaterialet med hensyn til den nødvendige fugtning og æltning før afhakning. Ved denne fremstil-30 lingsmetode tilvejebringes der granulater af ikke kug le-formet karakter, hvilket er uhensigtsmæssigt ved belastning af granulaterne, f.eks. ved lagring eller transport, således at der let bliver tale om et vist materialespild.In the colander principle, the raw material is subjected to wetting through a snail conveyor, a grinder on a humidifier, and typically passes a shake screen or, via a so-called "meat chopping machine" principle, through a hollow plate provided thereto into a kneaded material. number of webs 25 and chopped off at appropriate lengths. This manufacturing process also involves relatively high costs, which also requires extensive pre- and post-processing of the raw material with regard to the necessary wetting and kneading before cutting. In this preparation method, non-spherical granules are provided, which is inconvenient when loading the granules, e.g. by storage or transport, so that a certain amount of material wastage is easily encountered.

DK 159643 BDK 159643 B

22

Man har således udviklet et granuleringssystem, som betjener sig af en i og for sig kendt rotationsblandemaskine, der i kombination med en ny fremgangsmåde har vist sig fordelagtig til fremstilling af granulater.Thus, a granulation system has been developed which operates by a rotary mixing machine known per se, which in combination with a new method has proved advantageous for the production of granules.

5 Blandekarret er her fyldt med et lag af kugleformede emner, såsom sten eller lignende. Det at anvende sådanne emner i en roterende blandebeholder kendes i forbindelse med såkaldte kuglemøller, men hvor formålet her i modsætning til nærværende er at opnå en findeling af mate-10 rialer.Here, the mixing vessel is filled with a layer of spherical objects, such as stones or the like. The use of such articles in a rotary mixing vessel is known in connection with so-called ball mills, but the object here, in contrast to the present, is to obtain a comminution of materials.

I ansøgerens patentansøgning nr. 1026/87 indleveret den 27. februar 1987 er angivet en fremgangsmåde af den omhandlede art, ved hvilken der som bearbejdnings-beholder anvendes et om en lodret akse roterende og 15 med skrabeorganer udstyret kar, hvis bund er dækket med et lag i hovedsagen kugleformede bearbejdningslegemer, og hvor det tilførte materiales fugtighedsgrad reguleres før eller efter tilførslen, hvorved materialet efter en vis behandlingstid sætter sig som skaller på bearbejd-20 ningslegemerne og efter en vis tids yderligere bearbejd ning skaller af for til sidst at blive dirigeret ud gennem en rist i bunden af karret.The applicant's patent application No. 1026/87 filed on February 27, 1987, discloses a method of the kind in which a working container rotating about a vertical axis and scraping means equipped with a bottom is covered with a working container. layers, generally spherical machining bodies, where the moisture content of the applied material is controlled before or after application, whereby the material settles after a certain processing time on shells on the machining bodies and after a certain period of further processing shells to eventually be routed out through a grate at the bottom of the tub.

Ved denne fremgangsmåde har det vist sig muligt med lave omkostninger at fremstille stabile granulater, 25 f.eks. med en største dimension af størrelsesordenen 0,5-6 mm.In this process it has been found possible to produce stable granules at low cost, e.g. with a largest dimension of the order of 0.5-6 mm.

Den foreliggende opfindelse er baseret på den erkendelse, at der kan opnås tilsvarende gode resultater i en bearbejdningsbeholder med vandret omdrejningsakse, og det 30 ejendommelige ved fremgangsmåden ifølge opfindelsen i overensstemmelse hermed er angivet i krav l's kendetegnende del.The present invention is based on the recognition that similar good results can be obtained in a horizontal rotary axis machining vessel, and the characteristic of the method according to the invention is set forth in the characterizing part of claim 1.

Claims

5 As these continue to roll, push, slide, and strike against each other, the now dry material crumbles and breaks into smaller pieces in the form of a granule that is immediately removed from the rotating container via the grate. Other convenient details are set forth in claims 10 2-5. 1. A method of granulating a material such as lime powder or the like, and wherein the material is mechanically processed in a processing container, characterized in that this and / or any associated mixing means can rotate about a horizontal or oblique axis of rotation and has a content of loosely machined bodies whereby the rotational speed during operation is kept at such a low value that the machining bodies remain in mutual contact; the material is fed or imparted with a moisture content to adhere to the working bodies; and the rotation is continued until the material has become so dry that it peels off the machining bodies like a granulate which is discharged from the container through a grate.

Process according to claim 1, characterized in that the machining bodies are made of metal, e.g. steel or aluminum, ceramic material, quartzite, densite or stone, e.g. ball flint and that their diameter is between 10 and 200 mm. DK 159643 B

Process according to claim 1 or 2, characterized in that the moisture content of the feed material is adjusted to between 5 and 50%, preferably between 5 and 15%.

4. A process according to claim 1, 2 or 3, characterized in that a binder is added to bond the material in the individual granules, e.g. bentonite, hydrate lime, burnt clay, cement, carboxymethyl cellulose, tar substances, glue or peridur.

Process according to any one of the preceding claims, characterized in that the processing time is 2-60 minutes, preferably 5-10 minutes.