NO172424B

NO172424B - PROCEDURE AND DEVICE FOR CONTINUOUS STATIC THIN LAYER MIXTURE

Info

Publication number: NO172424B
Application number: NO914436A
Authority: NO
Inventors: Hans Hiorth
Original assignee: Hans Hiorth
Priority date: 1991-04-05
Filing date: 1991-11-13
Publication date: 1993-04-13
Also published as: NO172424C; NO914436L; NO914436D0

Description

Oppfinnelsen angår en fremgangsmåte og.anordning for mengde-gulering av komponentene som mates inn i en kontinuerlig, The invention relates to a method and device for quantity control of the components that are fed into a continuous,

statisk blander av tynnskikttype. Anordningen regulerer direkte spalteåpningen i de ringdysene som omdanner komponentstrømmene til tynnskikt i blandeapparatet, slik at tykkelsene på skiktene og derved gjennornstrømningsmengden kan reguleres. static mixer of thin layer type. The device directly regulates the slot opening in the ring nozzles that convert the component flows into thin layers in the mixing apparatus, so that the thicknesses of the layers and thereby the amount of recirculating flow can be regulated.

Kontinuerlig statisk blanding kjennetegnes generelt ved at komponentene mates fortløpende og med stor hastighet inn i et blandeapparat uten bevegelige deler, hvor kun bevegelsesenergien benyttes for blanding. Dette i motsetning til batchblanding med chargevis mating, og som ved hjelp av røreverk eller omveltning av massen bevirker blanding. Continuous static mixing is generally characterized by the fact that the components are fed continuously and at high speed into a mixing device without moving parts, where only the energy of movement is used for mixing. This is in contrast to batch mixing with batchwise feeding, which uses a stirrer or overturning of the mass to effect mixing.

Blandeprosesser inngår idag i nesten all prosessindustri. For å spare energi, investeringer, arbeidskraft m.m. går man nå mer og mer bort fra batchblanding og over til kontinuerlig blanding. Foreliggende fremgangsmåte og reguleringsanordning øker anvendel-sesområdet for tynnskiktblanding slik at blandesysternet vil få Mixing processes are today included in almost all process industries. To save energy, investments, labor etc. you are now moving more and more away from batch mixing and over to continuous mixing. The present method and control device increase the range of application for thin-layer mixing so that the mixing system will have

økt anvendelse innen råvarekombinasjoner som: Pulver/pulver, pulver/væske, væske/væske og pulver-el. væske/gass, damp el. luft og for spesialtilfeller: Stor mengde/liten mengde. increased use within raw material combinations such as: Powder/powder, powder/liquid, liquid/liquid and powder-electricity. liquid/gas, steam etc. air and for special cases: Large quantity/small quantity.

For kontinuerlig statisk tynnskiktblanding gjelder at blandingen foregår i et blandehode hvor fortrinnsvis en fluidisert pulver-komponent eller suspensjon mates inn aksielt ovenfra, og hvor en væske eller gasskomponent har et radielt innløp. Råvarene står under et moderat overtrykk før de gjennom av/på-ventiler føres inn i blandehodets dyser hvor statisk trykk omsettes til beveg-elsesenergi. Tynnskikt dannes av den aksielle komponentstrøm ut av dysen når denne spres utover en underliggende konflate mens tynnskikt av den radielt innførte komponent dannes i ringdyser. For continuous static thin-layer mixing, the mixing takes place in a mixing head where preferably a fluidized powder component or suspension is fed in axially from above, and where a liquid or gas component has a radial inlet. The raw materials are under a moderate overpressure before they are fed through on/off valves into the nozzles of the mixing head, where static pressure is converted into movement energy. Thin layers are formed by the axial component flow out of the nozzle when this is spread over an underlying conflate, while thin layers of the radially introduced component are formed in ring nozzles.

Ved at tynnskiktene møtes i en fritt flytende cirkulær blandesone, oppnås en momentan blandeeffekt med momentan viderebe-fordring av blandeproduktet ut av blandesonen. Best blanderesul-tat oppnås i en blandesone hvor et nedadrettet skikt av aksielt innført råvare møter et skikt utenfra og et skikt innenfra av By the fact that the thin layers meet in a free-flowing circular mixing zone, an instantaneous mixing effect is achieved with instantaneous further transport of the mixing product out of the mixing zone. The best mixing result is achieved in a mixing zone where a downwardly directed layer of axially introduced raw material meets a layer from the outside and a layer from the inside of

den radielt innførte råvare. Det vil si at den radielle råvare-strømmen fordeles til en ringdyse på utsiden og en ringdyse på innsiden av blandesonen. the radially introduced raw material. That is, the radial raw material flow is distributed to an annular nozzle on the outside and an annular nozzle on the inside of the mixing zone.

Hittil har ikke tynnskiktblandemetoden fått vesentlig utbredelse. Dette skyldes at den ikke har innbefattet en effektiv fremgangsmåte og anordning for å stille inn råvaremengden før man starter blandingen og mulighet til å kunne justere mengdene under blanding. Med vanlige trykk mengdereguleringsventiler foran blandehodet vil man riktignok kunne regulere mengdene, men da vil utløpshastig-heten fra dysene bli forskjellig med uforandret dysetversnitt. Dessuten vil disponibelt trykk som kan omsettes til hastighet i dysen bli redusert i nevnte ventilsystem. So far, the thin-layer mixing method has not been widely used. This is because it has not included an effective method and device for setting the quantity of raw material before starting the mixture and the possibility of being able to adjust the quantities during mixing. With normal pressure quantity control valves in front of the mixing head, it will indeed be possible to regulate the quantities, but then the outlet velocity from the nozzles will be different with an unchanged nozzle cross-section. In addition, available pressure that can be converted into velocity in the nozzle will be reduced in the aforementioned valve system.

Ved foreliggende oppfinnelse skjer reguleringen i ringdysene på en slik måte at utløpshastigheten holder seg tilnærmet konstant selv om man regulerer gjennomstrømmet mengde. Ifølge konstruksjonen blir mengdene regulert ved hjelp av bevegelige dyseflater inne i blandehodet og ved at bevegelsene blir over-ført til betjeningsorgan på blandehodets utside. Ved å stille inn betjeningsorganene på forhånd kan mengdene fastlegges før blandingen begynner og videre kan justering utføres under blanding. In the present invention, the regulation in the ring nozzles takes place in such a way that the outlet speed remains approximately constant even if the amount flowing through is regulated. According to the construction, the quantities are regulated by means of movable nozzle surfaces inside the mixing head and by the movements being transferred to an operating device on the outside of the mixing head. By setting the controls in advance, the quantities can be determined before mixing begins and further adjustments can be made during mixing.

Normalt vil også hver råvaretilførsel ha sin egen utenforliggende av/på ventil. Disse vil ved dette system fortrinnsvis bli brukt til start/stopp av blandeprosessen. Normally, each raw material supply will also have its own external on/off valve. In this system, these will preferably be used to start/stop the mixing process.

Ovenfor nevnte fordeler ved denne mengderegulering oppnås ved The above-mentioned advantages of this quantity regulation are achieved by

at dysene har en fast og en koaksialt bevegelig konflate. Ved å aksialforskyve de bevegelige konflater i forhold til de faste ved for eksempel gjengeforbindelser, forandres de cirkulære dyseåpninger. Derved forandres tykkelsen på skiktene som strømmer ut og dermed mengdene. Det vil si at med konstant trykkfall over dysen og konstant utløpshastighet kan blandeforholdet reguleres. Med nevnte gjengeforbindelse vil en viss vinkelinnstilling til-svare en bestemt dyseåpning. Tilhørende mengde vil kunne avleses på skalaer på utsiden av blandehodet. that the nozzles have a fixed and a coaxially movable conflate. By axially displacing the movable conflates in relation to the fixed ones by, for example, threaded connections, the circular nozzle openings are changed. This changes the thickness of the layers that flow out and thus the quantities. This means that with a constant pressure drop across the nozzle and a constant outlet velocity, the mixing ratio can be regulated. With said threaded connection, a certain angle setting will correspond to a specific nozzle opening. The corresponding amount can be read on scales on the outside of the mixing head.

For industriell anvendelse er mengdebestemmelsen av komponentene vanskligere ved en kontinuerlig prosess enn ved batchprosesser hvor eksakt innveiing foretas for hver råvare. Ved kontinuerlig blanding har man kontinuerlige målemetoder for råvarene før de blandes, men disse gir ikke ønsket nøyaktighet og anvendelighet. Ved foreliggende blandemetode er derfor den direkte regulering ifølge oppfinnelsen et alternativ eller supplement ved kontinuerlig blanding. Et reguleringsproblem ved andre kontinuerlige blandeprosesser er korrekt blandeforhold i start/stopp fasene. Foreliggende blande og reguleringsmetode med kort og tilnærmet samme gjennomløpstid for råvarene og momentanblanding, som kom-binert med forhåndsinnstilling av blandeforholdet, gir derimot korrekt blandingsforhold også ved start/stopp. For industrial use, the quantity determination of the components is more difficult in a continuous process than in batch processes where exact weighing is carried out for each raw material. With continuous mixing, you have continuous measuring methods for the raw materials before they are mixed, but these do not provide the desired accuracy and applicability. In the present mixing method, the direct regulation according to the invention is therefore an alternative or supplement to continuous mixing. A control problem with other continuous mixing processes is the correct mixing ratio in the start/stop phases. The existing mixing and regulation method with short and approximately the same lead time for the raw materials and instantaneous mixing, which combined with pre-setting the mixing ratio, on the other hand, gives the correct mixing ratio also at start/stop.

Fremgangsmåte og reguleringsanordning ifølge oppfinnelsen frem-går av tegningen som med beskrivelse refererer til et blandehode i to utførelser spesielt for pulver/væske blanding: Fig. 1 viser snitt av blandehode med tilførsel til indre væske-dyse gjennom rørribber lagt gjennom utstrømmende ferdigblanding. Fig. 2 viser snitt av blandehode med tilførsel til indre væske-dyse gjennom rørribber lagt gjennom pulverstrømmen inn. Fig. 3 viser skjematisk en blandeprosess hvor flere blandehoder inngår. Method and control device according to the invention can be seen from the drawing, which with description refers to a mixing head in two versions especially for powder/liquid mixing: Fig. 1 shows a section of mixing head with supply to internal liquid nozzle through tube ribs laid through flowing finished mixture. Fig. 2 shows a section of the mixing head with supply to the internal liquid nozzle through pipe ribs laid through the powder flow. Fig. 3 schematically shows a mixing process where several mixing heads are included.

På fig 1 sees nedre del av utløpstrakt (2) i en trykkbeholder inneholdende fluidisert pulver (1) som ved åpning av en på/av ventil (3) åpner for aksiell pulverinnføring til blandehodet. Tilsvarende åpner på/av ventil (23) samtidig for den radielle innføring av en væskekomponent (21) som står under tilsvarende trykk. Figure 1 shows the lower part of the outlet funnel (2) in a pressure vessel containing fluidized powder (1) which, when an on/off valve (3) is opened, opens for axial powder introduction to the mixing head. Correspondingly, the on/off valve (23) simultaneously opens for the radial introduction of a liquid component (21) which is under corresponding pressure.

Blandehodets hoveddel er hus (4) med innvendige dyser og fordel-ingskanaler. Husets øvre del (5) har et innadrettet radielt ribbesystem (6) med feste for en sentral del (7). Konsentrisk og utenforliggende er en aksielt forskyvbar reguleringsdel (8). Delene (7) og (8) utgjør øverst pulverdysen med fast konflate (10) og The main part of the mixing head is the housing (4) with internal nozzles and distribution channels. The upper part of the housing (5) has an inwardly directed radial rib system (6) with attachment for a central part (7). Concentric and external is an axially displaceable regulating part (8). The parts (7) and (8) make up the powder nozzle at the top with fixed conflate (10) and

en stillbar konflate (11). Del (8) har utvendig en øvre sylind-risk flate som glir mot innvendig flate i del (5). Nedre ytter-flate i del (8) har utvendige gjenger (9) i inngrep med gjengene i hus (4). Del (7) har under dysen en spredeflate (12) hvor tynnskiktet dannes. Mengdereguleringen skjer der konflaten (11) ved aksialforstilling regulerer skikttykkelsen mot spredeflate (12) der skiktet er tykkest slik at størst mulig klumper kan passere. Konflaten (13) har et klaringsvolum mot pulverskiktet som ved hjelp av hull (17.) i del (8) gir en mulighet for avluft-ing eller innføring av en tredje råvare. Nederst på konflate (12) der pulverskiktet har nådd minste tykkelse, blir skiktet nedad- an adjustable conflate (11). Part (8) has an outer cylindrical upper surface that slides against the inner surface in part (5). The lower outer surface in part (8) has external threads (9) in engagement with the threads in the housing (4). Part (7) has a spreading surface (12) under the nozzle where the thin layer is formed. The quantity regulation takes place where the conflating surface (11) by axial adjustment regulates the layer thickness towards the spreading surface (12) where the layer is thickest so that the largest possible lumps can pass. The conflate (13) has a clearance volume against the powder layer which, by means of holes (17) in part (8), provides an opportunity for venting or introducing a third raw material. At the bottom of the cone surface (12), where the powder layer has reached its minimum thickness, the layer is

rettet i møte med konflate (13) før blandesone (14). directed to meet the conflate (13) before the mixing zone (14).

Den radielt innførte væskemengde (21) føres inn i hus(4)til ringkammer (24) hvor halvparten går ut gjennom en innadrettet ringdyse med fast konflate (25). Resten av væsken går fra ring-kammeret gjennom et antall radielt innadrettete rørribber (26) The radially introduced amount of liquid (21) is fed into the housing (4) to the annular chamber (24), where half exits through an inwardly directed annular nozzle with a fixed conflate (25). The rest of the liquid passes from the ring chamber through a number of radially inwardly directed tube ribs (26)

til et sentralt fordelingskammer (32) med en utadrettet ring- to a central distribution chamber (32) with an outward-facing ring

dyse med fast konflate (27). Tynnskiktene fra ytre og indre ringdyser treffer det nedadrettete pulverskiktet utenfra og innenfra i blandesone (14). Ribberørene forbinder også del (30) nozzle with fixed conflate (27). The thin layers from the outer and inner ring nozzles hit the downwardly directed powder layer from the outside and from the inside in the mixing zone (14). The ribbed tubes also connect part (30)

med del (31) til en skive hvor gjenger" (33) ved dreing regulerer dyseåpningene paralelt mellom de faste konflåtene (25) og (27) with part (31) to a disk where threads" (33) when turned regulate the nozzle openings parallel between the fixed cone floats (25) and (27)

og de stillbare konflåtene (28) og (29). Ferdigblandingen fra blandesonen passerer gjennom åpningene mellom rørribbene. Skiven dreies med spak (34) med viser (35) mot fast skala som angir skikttykkelse og mengden ut fra gitte driftsforhold. Tilsvarende reguleres pulvermengden med spak (15) med viser (16) mot tilsvarende skalaer. Ved fjernkontroll benyttes sylindre, stepmotor eller lignende kjente komponenter. and the adjustable cone floats (28) and (29). The finished mixture from the mixing zone passes through the openings between the pipe ribs. The disc is turned with a lever (34) with a pointer (35) against a fixed scale which indicates the layer thickness and the quantity based on given operating conditions. Correspondingly, the amount of powder is regulated with lever (15) with pointer (16) against corresponding scales. For remote control, cylinders, stepper motors or similar known components are used.

I fig. 2 er tilsvarende regulering vist for et blandehode for klebrig blandeprodukt. Her er rørribbene (45) plasert over pulverdysen og et tynnest mulig ribbesystem (48) er anvendt etter blandesonen. Derved oppnås større utløpsåpninger for blandeproduktet og bedre selvrensing av ribbene. In fig. 2, corresponding regulation is shown for a mixing head for sticky mixed product. Here the pipe ribs (45) are placed above the powder nozzle and the thinnest possible rib system (48) is used after the mixing zone. This results in larger outlet openings for the mixing product and better self-cleaning of the ribs.

Blandehodet har delt innføringsrør (43) med halve væsketilførselen til ringkanal (44) og videre gjennom rørribbene (45) til del (46) med sentrisk rørforbindelse til indre ringdyse (47). Resten av innført væskemengde går direkte til ytre ringdyse (49). Reguleringen av pulvermengde og væskemengde skjer som ved fig.l ved å variere skikttykkelsene mellom de faste og stillbare konflatene i de tre dysene. The mixing head has a split inlet pipe (43) with half the liquid supply to the ring channel (44) and further through the pipe ribs (45) to part (46) with a centric pipe connection to the inner ring nozzle (47). The remainder of the introduced liquid quantity goes directly to the outer ring nozzle (49). The regulation of the amount of powder and amount of liquid takes place as in fig.1 by varying the layer thicknesses between the fixed and adjustable conflates in the three nozzles.

I fig.3 er vist skjemtisk en prosessløsning bygget opp av flere blandehoder i serie. Et konkret eksempel er fremstilling av sementrelaterte produkter hvor hvert trinn leverer et aktuelt ferdigprodukt, men hvor dette også kan gå inn som råvare i etter-følgende trinn. For trinn I, II og III er skissert tilhørende blandehoder hvor: Fig.3 shows schematically a process solution made up of several mixing heads in series. A concrete example is the manufacture of cement-related products where each step delivers a relevant finished product, but where this can also be used as raw material in subsequent steps. For stages I, II and III, associated mixing heads are outlined where:

Al angir sement med eventuelle tilsatsstoffer. Al indicates cement with any additives.

Bl " vann " " Bl " water " "

Cl, Dl og B2 angir sementslurry for henholdsvis utstøpingsformål ved oljeboring, bygg og anlegg og som råvare for Cl, Dl and B2 indicate cement slurry respectively for casting purposes in oil drilling, construction and construction and as a raw material for

trinn II. stage II.

A2 og A3 angir sand og grus av forskjellig gradering A2 and A3 indicate sand and gravel of different grades

C2.D2 og B3 angir henholdsvis pussement, sprøytebetong og råvare C2.D2 and B3 indicate plaster, shotcrete and raw material respectively

for trinn III. for stage III.

C3 angir forblandet betong med C4 som ferdigbetong etter C3 indicates premixed concrete with C4 as ready-mix concrete after

tilleggsblanding i f.eks. skrue/pumpe utstyr. RA1.RB1 - RA3.RB3 angir mengdereguleringsanordninger. additional mixture in e.g. screw/pump equipment. RA1.RB1 - RA3.RB3 indicate quantity control devices.

Ellers inngår eventuelt de viste mellombeholdere, try!-kpumper Otherwise, the shown intermediate containers, try! pumps are included

og rør/slange transporter. and pipe/hose transport.

Fremgangsmåte og reguleringsanordninger etter samme prinsipper vil også gjelde spesialutførelser av blandehoder hvor mer enn to råvarer føres inn i samme blandehode. Slike ekstra råvarer vil fortrinnsvis baseres på ensidig innføring i eksisterende skikt for at blandehodet ikke skal bli for komplisert. Procedure and control devices according to the same principles will also apply to special designs of mixing heads where more than two raw materials are fed into the same mixing head. Such additional raw materials will preferably be based on one-sided introduction into the existing layer so that the mixing head does not become too complicated.

Tilslutt noen data fra produserte blandehoder med regulering ifølge oppfinnelsen: Trykkområdet for inngående råvarer for pulver og væsker 1-3 Bar hvilket tilsvarer tynnskiktshastigheter 10-15 m/sek. Tykkelse på pulverskikt 1-3 mm og væskeskikt 0,1-1 mm. Blandehodeydelse vil være et produkt av hastighet, skikttykkelse og blandesoneomkrets. For valgt blandesonediameter fra ca. 30-200 mm vil man kunne opp-nå kapasiteter i området 5-150 m^/time. Attach some data from manufactured mixing heads with regulation according to the invention: The pressure range for incoming raw materials for powders and liquids 1-3 Bar which corresponds to thin layer speeds 10-15 m/sec. Thickness of powder layer 1-3 mm and liquid layer 0.1-1 mm. Mixing head performance will be a product of velocity, layer thickness and mixing zone perimeter. For selected mixing zone diameter from approx. 30-200 mm it will be possible to reach capacities in the range of 5-150 m^/hour.

Claims

1. Method for regulating the quantity of the individual components (1, 21) of liquid and/or powdered and/or gaseous material that is fed through a static mixing head, where coaxial thin layers of the components are formed in coaxial ring nozzles and fed together in a common circular mixing zone (14), the number of components being at least two, characterized in that the thickness of the layers and thereby the quantity through the nozzles is regulated by varying the openings of the nozzles and that the variation in the openings is transmitted from adjustment mechanisms on the outside of the mixing head.

2. Method according to claim 1, where at least one of the coaxial ring nozzles has a fixed inner conflating surface (10, 12, 25, 27) and a movable outer conflating surface (11, 28, 29), characterized in that the movable outer conflating surface (11 , 28, 29) is adjusted axially so that the nozzle opening is regulated.

3. Method according to claim 2, characterized in that the movable outer contact surface (11, 28, 29) is adjusted by operating a coaxial threaded connection (9, 33), or a movable and coaxial, telescopic or similar system for providing movements in relation to a fixed part of the mixing head, possibly by remote control with mechanical, electrical, pneumatic or hydraulic transmission to operating devices (15, 34) on the mixing head.

4. Method according to claim 2 or 3, characterized by simultaneous regulation of at least two nozzles, the movable nozzle surfaces belonging to nozzle parts (31) connected with tubes (26) or ribs (48) between which the finished mixture passes, the tubes (26) possibly is used for rigid connection of the mentioned nozzle parts (31) and material transport of components between the co-regulated nozzles, and the ribs (48) are optionally used for rigid connection of the mentioned nozzle parts when material transport of components to co-regulated nozzles takes place via fixed, separate pipe connections (45) .

5. Device for regulating the quantity of the individual components (1, 21) of liquid and/or powdered material that is fed through a static mixing head, where coaxial thin layers of the components (1, 21) are formed in coaxial ring nozzles and fed together in a common circular mixing zone (14), characterized in that the openings of the nozzles are adjustable, and that adjustment mechanisms are arranged on the outside of the mixing head so that when these are operated, they cause variation in the openings and thereby regulation of the thickness of the layers.

6. Device according to claim 5, characterized in that at least one of the coaxial ring nozzles has a fixed inner conflate (10, 12, 25, 27) and a movable outer conflate (11, 28, 29), and where the movable outer conflate (11, 28, 29) is axially adjustable so that the nozzle opening can be regulated.

7. Device according to claim 6, characterized in that the movable outer conflate (11, 28, 29) is adjustable through a coaxial threaded connection (9, 33), or a movable and coaxial telescopic or similar system for providing movement in relation to a fixed part of the mixing head, as where appropriate, remote control devices are arranged for operating the adjustment mechanisms, with a mechanical, electrical, pneumatic or hydraulic transmission line to operating devices (15, 24) on the mixing head.

8. Device according to claim 6 or 7, characterized in that the movable nozzle surfaces for at least two of the nozzles belong to parts connected by pipes (26) or ribs (48) between which the finished mixture passes.

9. Device according to one of claims 5-8, characterized in that the mixing head comprises a number of N > 2 coaxial and adjustable ring nozzles as well as associated control devices for these, for mixing N components.

10. Use of one or more mixing heads according to one of claims 5-9 as elements in a process structure, possibly in combination with other equipment.