SE180089C1

SE180089C1 -

Info

Publication number: SE180089C1
Authority: SE
Publication date: 1962-01-01

Description

Uppfinnare: F J Clarke och T L Goldsmith Prioritet begard frail den 1* februari 1957 (Storbritannien) FOreliggande uppfinning hanfor sig till varmevaxlare for behandling av flytande eller halvflytande vatskor med hog viskositet och tathet (och speciellt sadana som ha benagenhet att hardna eller stelna vid avkylning eller upphettning), och vilka varmevaxlare dro av den typ som omfattar ett tunnvaggigt varmeoverforingsrar, en detta ror omgivande mantel samt en axel koncentriskt monterad i namnda ror och uppbarande skrapblad, varvid utrymmet mellan roret och manteln tjänst- gOren kanal, genom vilken ett kontinuer- ligt striimmande varme- eller kylmedium passerar. Utrymmet mellan roret och axeln liar ringa tjocklek och tjanstgor som en kanal, genom vilken ett tunt skikt av den behandlade flytande eller halvflytande vatskan kan passera, varvid skrapbladen aro anordnade att skrapa utmed det ndmnda rOrets insida nar axeln roterar, varigenom varje vidhAftande film av den flytande eller halvflytande vatskan avlagsnas under dennas passage genom den kanal som bildas mellan roret och axeln. Inventors: FJ Clarke and TL Goldsmith Priority requested from February 1, 1957 (United Kingdom). The present invention relates to heat exchangers for the treatment of liquid or semi-liquid liquids with high viscosity and density (and especially those which have a tendency to harden or solidify on cooling or heating), and which heat exchangers of the type comprising a thin-walled heat transfer tube, a jacket surrounding this tube and a shaft concentrically mounted in said tube and supporting scraper blades, the space between the tube and the jacket serving channel, through which a continuous flowing heating or cooling medium passes. The space between the tube and the shaft is of small thickness and serves as a channel through which a thin layer of the treated liquid or semi-liquid liquid can pass, the scraper blades being arranged to scrape along the inside of the said tube as the shaft rotates, whereby each adhesive film of the the liquid or semi-liquid liquid is deposited during its passage through the channel formed between the tube and the shaft.

For all fa en varmevaxlare av den omnfinmda typen att fungera tillfredsstallande är det nadvandigt att skapa storsta mOjliga grad av rorelse i det tunna skiktet av flytande eller halvflytande vatska under dess passage genom kanalen. Medan vid vatskor med lag eller medelhes viskositet en tillracklig rarelse framkallas genom verksamheten av de skrapblad som aro anordnade pa en rund axel, erfordras vid halvflytande vatskor, vilka med naturnadvandighet ha hog viskositet och eventuellt hog Whet, kraftigare atgarder for att skapa en tillracklig grad av rorelse, och det ãr foreliggande uppfinnings andamal att astadkomma de mera kraftigt verkande organ, som Aro nadvandiga for att erhalla en sadan rdrelse. In order for a heat exchanger of the type mentioned to function satisfactorily, it is necessary to create the greatest possible degree of movement in the thin layer of liquid or semi-liquid liquid during its passage through the channel. While in wet or medium viscosity wet shoes a sufficient effect is produced by the action of the scraper blades arranged on a round shaft, in semi-liquid water shoes, which by nature have a high viscosity and possibly high Whet, more vigorous measures are required to create a sufficient degree of and it is the object of the present invention to provide the more powerful means which are necessary to obtain such a movement.

Enligt uppfinningen astadkommes en roterande varmevaxlare fOr behandling av flytande eller halvflytande vatskor med hag viskositet och tathet, vilken varmevaxlare Or av det slag, som omfattar ett tunnvaggigt, av en mantel omgivet varmeoverforingsror saint en axel koaxiellt anbragt inuti roret och uppbarande skrapblad, varvid utrymmet mellan roret och manteln tjanstgor som en kanal f Or passage av ett kontinuerligt strommande varme- eller kylmedium, och utrymmet mellan raret och axeln har ringa radiell tjocklek och tjanstgOr som en inre kanal for passage av den flytande eller halvflytande vatska, som skall behandlas, och den roterande axeln ar forsedd med ett flertal plana eller rafflade sidoytor, som motas i langdriktningen i horn, vilka ligga narmare varmeoverforingsroret On de plana eller rafflade sidoytorna mellan hornen, och vilka darfor dela den inre kanalen i langs omkretsen fordelade, langsgaende, i forbindelse med varandra staende underkammare. Varmevoxlaren kannetecknas i forsta hand darav, att skrapbladen endast uppbdras pa nagra av rotoraxelns plana eller raffia-de sidoytor, mellan vilka andra plana eller rafflade sidoytor pa axeln befinna sig vilka sakna skrapblad, varigenom den flytande eller halvflytande vatska, som skall behandlas, under sin passage genom den inre kanalen utsattes for en skrapande och omr8rande verkan i de underkammare, som innehalla skrapblad, omvdxlande med en knadande verkan i de underkammare, vilka sakna skrapblad. According to the invention there is provided a rotary heat exchanger for treating liquid or semi-liquid liquids having high viscosity and density, which heat exchanger Or of the type comprising a thin-walled, heat transfer tube surrounded by a jacket saint a shaft coaxially arranged inside the tube and supporting intermediate scraper blades. the tube and jacket serve as a channel for the passage of a continuously flowing heating or cooling medium, and the space between the tube and the shaft has a small radial thickness and serves as an inner channel for the passage of the liquid or semi-liquid liquid to be treated, and the the rotating shaft is provided with a plurality of flat or knurled side surfaces, which are met in the longitudinal direction in horns, which lie closer to the heat transfer tube on the flat or knurled side surfaces between the horns, and which therefore divide the inner channel in circumferentially distributed longitudinally standing lower chambers. The heat exchanger can be characterized primarily by the fact that the scraper blades are collected only on some of the flat or ragged side surfaces of the rotor shaft, between which other flat or knurled side surfaces on the shaft are located which have no scraper blades, whereby the liquid or semi-liquid liquid to be treated passage through the inner channel was subjected to a scraping and stirring action in the sub-chambers containing scraper blades, alternating with a kneading action in the sub-chambers which lack scraper blades.

Uppfinningen kommer i det folj ande att beskrivas med hdnvisning till bifogade ritning: Fig. 1 dr en sehematisk tvarsektion av en rorformig varmevaxlare med skrapblad monterade pa en roterande axel med den van- 2— — Iiga cirkuIara tvarsnittsarean; samt fig. 2 till 6 aro liknande tvarsektioner visande samma rorformiga varmevaxlare med skrapblad monterade pa olika forbattrade typer av roterande axlar. The invention will be described in the following with reference to the accompanying drawing: Fig. 1 shows a sehematic cross-section of a tubular heat exchanger with scraper blades mounted on a rotating shaft with the usual circular cross-sectional area; and Figs. 2 to 6 are similar cross-sections showing the same tubular heat exchangers with scraper blades mounted on different improved types of rotating shafts.

Den i fig. 1 visade kanda varmevaxlaren har ett tunnvaggigt varmeoverforingsror 11 och ett mantelror 12, mellan vilka ror en ringformig kanal 13 finnes for ett kontinuerligt strommande varme- eller kylmedium. The jug heat exchanger shown in Fig. 1 has a thin-walled heat transfer tube 11 and a jacket tube 12, between which tubes an annular channel 13 is present for a continuously flowing heating or cooling medium.

Koncentriskt anordnad inuti roret 11 finnes en roterande axel 14 uppbarande tva skrapblad 15. Det ringformiga utrymmet 16 mellan axeln 14 och roret 11, och vars radiella utstrackning Ar nagot overdrivet framstalld i fig. 1, tjanstgor som en kanal, genom vilken den behandlade flytande eller halvflytande vatskan kan passera. Under drift, nar axeln 14 Mlles i rotation, avlagsna skrapbladen vane vidhaftande film av den flytande eller halvflytande vatskan fran varmeoverforingsrorets 11 insida. Concentrically arranged inside the tube 11 is a rotating shaft 14 carrying two scraper blades 15. The annular space 16 between the shaft 14 and the tube 11, and whose radial extent Ar is somewhat exaggerated in Fig. 1, serves as a channel through which the treated liquid or the semi-liquid liquid can pass. During operation, when the shaft 14 is in rotation, the scraper blades habitually remove adhesive film from the liquid or semi-liquid liquid from the inside of the heat transfer tube 11.

Som man ser har axeln 14 i den i fig. 1 visade kanda varmevaxlaren cirkular tvarsektion, medan motsvarande axlar i de utforingsformer av foreliggande uppfinning som visas I fig. 2-6 samtliga ha ieke-cirkular tvarsektion. As can be seen, the shaft 14 in the jug heat exchanger shown in Fig. 1 has a circular cross section, while the corresponding shafts in the embodiments of the present invention shown in Figs. 2-6 all have a non-circular cross section.

Enligt fig. 2 liar salunda axeln 17 kvadratisk tvarsektion; enligt fig. 3 an axeln 18 tiosidig med tva motstaende plana sidor forsedda med fastanordningar for skrapbladen 15, varvid de aterstaende atta sidorna aro urskalade; enligt fig. 4 har axeln 19 Attasidig tvarsektion med varannan sida plan och varannan urskalad; enligt fig. 5 har axeln 20 sexkantig tvarsektion med tre smala sidor som var och en dr forsedd med fastanordningar for skrapblad 15', varvid dessa smala sidor omvaxla med Ire bredare sidor; samt enligt fig. 6 har axeln 21 niosidig tvarsektion. Var tredje sida av denna axel utg8res av en smal plansida forsedd med fastanordningar for resp. skrapblad 15', varvid par av plana eller urskalade sidor aro anordnade mellan de smala, pa varandra foljande plansidorna. According to Fig. 2, the shaft 17 thus has a square cross section; according to Fig. 3 on the shaft 18 on either side with two opposite flat sides provided with fastening devices for the scraper blades 15, the remaining eight sides being peeled off; according to Fig. 4, the shaft 19 has an obverse side section with each other side flat and every other peeled off; according to Fig. 5, the shaft 20 has a hexagonal cross-section with three narrow sides, each of which is provided with fastening devices for scraper blades 15 ', these narrow sides alternating with slightly wider sides; and according to Fig. 6, the shaft 21 has a nine-sided transverse section. Every third side of this shaft consists of a narrow plan side provided with fastening devices for resp. scraper blade 15 ', with pairs of flat or peeled sides arranged between the narrow, successive flat sides.

Claims

Patent claim:

A rotary heat exchanger for the treatment of liquid or semi-liquid liquids with high viscosity and density, which heat exchanger is of the type comprising a thin-walled, heat transfer tube surrounded by a jacket and a shaft coaxially arranged inside the tube and supporting scraper blades, the space between the jacket serves as a channel for the passage of a continuously flowing heating or cooling medium, and the space between the tube and the shaft has a small radial thickness and serves as an inner channel for the passage of the liquid or semi-liquid liquid to be treated, and the rotating shaft is provided with a plurality of flat or knurled side surfaces which meet in the longitudinal direction in the corners, which lie closer to the heat transfer tube than the flat or knurled side surfaces between the horns, and which therefore divide the inner channel along the circumferentially distributed, longitudinal, interconnected lower chambers, .ray, that the scraper blades (15 or 15 ') are only supported on some of the flat or knurled side surfaces of the rotor shaft (17, 18, 19, 20 or 21), between which other flat or knurled side surfaces on the shaft are located which have no scraper blades, whereby the liquid or semi-liquid liquid to be treated during its passage through the inner channel was subjected to a scraping and agitating action in the lower chambers containing scraper blades, alternating with a kneading action in the lower chambers which lack scraper blades.

Rotary heat exchanger according to claim 1, characterized in that the scraping edge of each scraper blade (15 or 15 ') extends in the circumferential direction outside the flat or knurled side surfaces of the rotor shaft on which the scraper blade is mounted. Request publications: Patents in Sweden 137 693; USA 1 847 149.