CA2002835A1 - Method of separating a substance from a liquid by means of a particulate material - Google Patents
Method of separating a substance from a liquid by means of a particulate materialInfo
- Publication number
- CA2002835A1 CA2002835A1 CA 2002835 CA2002835A CA2002835A1 CA 2002835 A1 CA2002835 A1 CA 2002835A1 CA 2002835 CA2002835 CA 2002835 CA 2002835 A CA2002835 A CA 2002835A CA 2002835 A1 CA2002835 A1 CA 2002835A1
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- CA
- Canada
- Prior art keywords
- liquid
- particles
- substance
- flow
- layer
- 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.)
- Abandoned
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/02—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor with moving adsorbents
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2215/00—Separating processes involving the treatment of liquids with adsorbents
- B01D2215/02—Separating processes involving the treatment of liquids with adsorbents with moving adsorbents
- B01D2215/029—Centrifuge-like arrangements
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- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Centrifugal Separators (AREA)
- Treatment Of Liquids With Adsorbents In General (AREA)
Abstract
Abstract In connection with separation of a substance from a liquid by binding said substance to small particles, for instance solids, a body of liquid is kept in rotation together with the particles having a density lower than that of the liquid. Liquid from which said substance is to be separated is brought into contact with the particles in a way such that these are maintained suspended in the rotating liquid body.
Description
~002835 , . , The present invention relates to a method of separating a substance from a liquid by binding the substance to a particu-late material. By a particulate material is meant in this connection any suitable material in a finely divided form, thus 5 comprising not only solids but also particles of a more or less liquid material, for instance gel particles. The particles may be porous or impervious to liquid. Preferably, they are ~ chemically stable, and in certain applications of the invention : they have to be inert to the liquid, with which they are to come 10 into contact, and/or to the substance or substances which t,hey are to separate from the liquid. Even if the particles may have any suitable form they are preferably spherical and substan-tially of the same size.
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15 Separation by means of so called liquid chromatography tradi-tionally means that a liquid, from which a substance is to be separated, is caused to pass through a treatment chamber filled with a lot of small particles retained closely packed together in the treatment chamber between two perforated end walls. The ~ 20 liquid thus has to flow through the interspaces between the J, immobilized particles, the substance to be separated being retained by means of the particles by adsorption at their 8urfaces or in some other way.
25 A problem in connection with this separation technique is that the flow resistance for the liquid is very large in the inter-spaces between the particles. The smaller the particles are, the larger this flow resistance will be. The liquid thus has to be highly pre6surized to be able to pass through the interspaçes ~ 30 between the particles. The problem is accentuated by the fact 3 that the particles preferably are made as small as possible, since a certain volume of packet particles exposes a larger total particle surface to a through-flowing liquid the smaller ~ the particles.
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--` Z~)02835 For ~hese reasons it ls difflcult to provide for acceptable costs a separation plant having a large separation capacity, and the described separation technique, therefore, is mainly utillzed in a small scale, e.g. for analysing purposes or for the separation of very small amounts of very expensive substances.
As an alternative to the above described separation technique it has been suggested that a liquid, from which a substance is to be separated, be supplied to the lower part of a treat-ment chamber containing a bed of particles, which are free~to move relative to each other, and then be caused to flow through the bed of particles from below , upwardly in a way such that the particles are maintained in a fluidized or suspended state within the treatment chamber.
A fluidizing technique of this kint would require a smaller overpressure of the supplied liquid than the previously described separation technique. However, the capacity of a separation plant in this case woult instead be limited by the I fact that the flow velocity of the liquid through the bed of ¦ particles could not be too large. This flow velocity must not ¦ be larger than that required to retain the particles in the bed by gravity and not b~ elltrained by th~ ~pwaraly flow~ing liquid and thereb~ carried out of the treatment chamber.
One further technique suggested to bind a certain subtance in a liquid to particles resides in keeping the particles suspended in the liquid by agitation for some time ant then - after the particles have attracted the said substance in the liquid - separating the particles from the liquid by gravity separation or centrifugal force separation. A disadvan-tage of this technique is that it will take a relatively long time to create the required contact between the particles and ~ 35 all parts of the liquid for the separation of the substance i therein-~, .
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;~ 0 0 2 8 3 5 The present invention provides a new method of sep&rating a substance from liquid by blnding the substance to small partLcles, which method makes it possible to obtain a substantially larger separation capaclty than the 5 above described methods and, thus, can be used in a much larger scale than these methods. The invention also enables the use of substantially smaller pa~ticles than could be used ln the prior art.
10 These results are obtained according to the invention by keeping a body of liquid having a predetermined density in rotation together with small particles having a density lower than that of the liquid, and by bringing liquid, from which said 3 substance is to be separated, into contact with the particles in 15 a way s~ch that the particles are maintained suspended in the rotating liquid.
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The invention consequently resides in keeping particles lighter than a liquid in a suspended state in a rotating liquid body, 20 while the liquid, from which a substance is to be separated, is caused to flow past the suspendet particles.
'~ If desired, the partlcles may be kept suspended in the whole of~, the rotatlng llquld body. Preferably, however, the partlcles are 25 kept suspended only in a layer of the liquid body, the liquid to ~ be freed from said substance being caused to flow through the q suspensi~n layer. The main part of the liquid should flow bet-ween the suspended particles in a directi,Qn from the rotational ;j axis of the rotatlng liquld body outwardly towards the radially~ 30 outermost part of the liquid body.
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~ Slnce the particles are lighter than the llquld, the particles ; suspendet in the liquid will try,due to the centrifugel force,to ;~ move radially inwards, the force influencing the particles in ~ 35 this direction being larger the furtherfrom the rotational axis :~;, ,. ; , . -:~......... ; , : ., .
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the particles are situated. Therefore, the supply of liquld from which said substance ls to be separated may be made very large without any risk that the particles should leave the treatment chamber together with radially outwardly flowing liquid. The force to which the particles are sub~ected by the flow of the supplied liquid is independent of the distance between the ; particles and the rotational axis.
If the particle size would vary somewhat in the suspension layer, this does not matter very much, since extremely small particles which are easily entrained by the supplied liquid will still be retained in the vicinity of the other particles as a consequence of the radially outwardly increasing centrifugal force. By the same mechanism a particle is immediately returned ratially inwardly, if it has been influenced by occasional forces and been transferred too far out from the rotational axis.
The liquid body kept in rotation may have any desired shape.
If it has a shape such that the through-flow ~ection for the supplied liquid increases radially outwardly, the balanclng effect on the suspended particles will be even larger, since the force acting on the particles and caused by the flow of the liquid in this case decreases with increasing distance from the rotational axis of the liquid body, whereas the centrifugal force, acting in the opposite direction, increases.
An increasing through-flow section for the supplied liquid may be desirable, particularly in the radially outer part of the-suspension layer, for safe retainment of the particles therein.In the main part of the suspension layer it may be desirable, however, to have instead a radially outwardly decreasing through-flow section for the supplied liquid. Thereby, namely, it may be accomplished if desired a substantially uniform distribution of the particles in the suspension layer along the .~ . . - . , .
flov path ofthe llquld thercthrough If the partlcle~ h~ve -cert~n ~lze dl~trlbutlon, tbld haJ to bs conrldered ln connectlon wlth the p1~ning of tbe flo~ path of the liquid throu~h the 4u~pen~10n l~yer or e~tabllRhIn2 ~ de~lrea dl-trlbutlo~ o~ the partlcle~ ther~ln ould be ob~lou~, ~ny deslr~d di~tance botween the psrticl--in the ~u8pe~100 layer ~J b- cco~pll~hed b~ ~ ~ult~bl~ cholcc of centrlfug~l force ~ehlD 8~t llquld flow through the ~u~p~n-~lon lAyer ~hl~ tlst~nce mAy ~ou bc chnng~d by controlllng ofthe cenerlfu~al ~orce ~nt/or the llqult flo~ durlng the co~r~o of the ~cpArntlon procs~-If tesired, lt 18 po~s~ble by uoln~ p8rtlcle~ of dlfferent ~l~es to obtcln dlfferent (oep8rste or overl-pplng) l-~er~ of ~urpen-ted psrtlc1-~ ln the rotatlng llquld body. ~ could be 8~ful ln conne~tlon wlth b~tch-~ise u~e of partlcla~ durlng a ~cp-r-~
i tlng operselon 1~ order to ll~lt the r-dl-l ~ove~ent of tb~
particlo~ wlthln the ~uspenslon l-yer of the rot~tlng llquld boty Atv~nt~$oou-ly, o con~8ntloo-1 c-ntrli'~g~ p r-tor bal~ only ln~lgnlflc-ntl~ ~odl~l~d -~ bc ~ed for eh~ p~rfor~ln~ of the cthod ~ccordln~ to th~ ln~entloo~ both oald llquld ~nd tbe p rtlcles belng kept ln rot-t~oo 1~ the i~or~ of ~ ub~t~ntlelly ~nnul~r body Th~ lo~entlon ~ay be u~ed lo coonoctlo~ wlth ubst~ntl~
ep-r-tion proce~e~ of ~ klnd ln ~hlch coo~ntlon-l liqu~d cbrc~tography could co~e ~nto qu-rtloa Furth-r~ore, the lnventlon ~ke~ lt po~lble by ee-~ of th~ ~epar-tLon technlqu-her~ ln qu&~tlon to re~olve - y cp-r-tlon problemJ ~hlch at pre-enc cannot b~ recol~ed ln ~ econo~Lcall~ ccept-ble vCg Thu~, the ln~ntlon nake- lt por~ble ~n an lndu~trlal ~c-l~ to ~parate ~ery ~all ~ount~ of ~clu~blQ or hA~mful ~ub~tance~
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fr~ l~r~e ~ount~ of hesvlly t~lut-t ~olut~on- ~or IQ~t~nc~, th- lnvent~on ~y b- u-ed for ~xtr~ctln~ v-l~ blc net~ uch s p ld nd ~llvor, fro~ ~olutlon~, or ~or ostr-ctSng proteln-, polypoptlde~ or a~lno~cld- fro~ blotechnlcal proce-- llquld~.
Al~o c-rbohy~rate~ snd llplde~ ccn be extracted. Furtber-ore, the qu-l~ty of cort-ln trln~r, uch 4 be~r or ~lne, ~ay be l~proved by re~oval of cert~ ubat-nce~. Another o~
th-t wa~te ~ater nay be purlfl~t fro~ uod-Rlrod ~ub-t~nce~, ~uch a~ heavy ~etal~, phenole- or cy-nldo, befor~ lt 1~ du~ped 1~ ehe n-ture :.
The cholce of ~Aterl~l foe the p-rtlc~-~ to ~e u~ed ~c~ to b~
c~de wlth reg-rd to tho llqu~d ~ro~ ~hlch a ~ub~tance ~hould be ~ep~rat~d and to ~ald ~ub-tanc~. Slnc- ~Ang proces~ llquld- h-vo 15 a tens~ey of about 1,0 g/c 3. p~rticloc h-vl~ d-n~ley low-lr than 1,0 g/c~3 often have to bn ¢h4~0n. Then, dlffer-nt ~l~dr of pla~tlc ~terl~ y co C icto que~tlon. rOr ln~tcnce pol~-- ethene or polypropene ~sy be u~ed A~ a b sic o terl-l ln tho partlclc~. ~o~Qver, ~at-rl-l ha-vler th-n 1,0 g/c~3 ~y b-20 u~e,ll, if partlcl~ of l~uch -terl-l re e~pJInte,a by ~e-n- of pre~iou-ly known t-chn1qu~, c~h th~t they wlll conteln a Sac ol on- ~lnt or Aaother P~rtlcl-c of thl- ~lnd bc~g de7~clt~ e-lo~ ~ 0~04 s/c~3 ra A-~ll-bl~ on thc u-rktt.
25 I7~ th- a~o- u~nn-r ~ n-r~lly bno~n In connectlon ~lth con~cAtlo?~al llqult chro~to~raph~ tho p FtlCl~ to bc u-ed for th~ m~thod cccordln~ eo th- Inv ntlo~ aors-ll~ h-vc to S~
pr-p ect cuCh th t they ca~ attr-ct or b~nd a cubstc~c- to bc ~e?p r-tod froo llquld. In on~ v~ or ~noth-r - of c~vcral 30 ~no~n ~ay- - t~c p~rtlcle- r- glv~n ?~ ctl~e ~urÇ-c~ ~bleh ` for ln-t-nce chc~lc-lly or ph~lccll~ olnd -~d ~bc~ancc i to ehe p-rtlclec, ~hen llquld ~at~ l~to cont~ct there~lth, ~or ? ln~t-ncc, lt 1- po--lbl- to ~1~ th- p~rtlcl~ urf-ce- c-rt d n`? chJrRln~, ~0 th-t th-~ c n tt~ ct nd blnd p~rtlcul-tc ~ub-t-n-35 c~ h~ln~ thc oppo-lta ch rslns ~lon e~chc~ge technlqu-). E~e ,~
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6 a ~ell known pr~ncl~loo ~or oo cnll~t fflnl q -chrooatoaraph~, hydrofob~c lnter~ctlon, tc , ~Ay b~ uuod ln connectlon wlth the pre~ont lnventlon~
It 1~ o po~lble to uoe p~rtlcl~- hevlng the blllty of ab-orblng a ~ub~t-nce ln llq~ld. In euch c~eo~ the aubst-nce penetr~tes lnto th- p rtlclo body ln quo~tlon, ~her- lt 1 reta~ned~
AA ln connectlon wlth conventlonal llq~ld chro~ tography lt 1-often de~lred that the p-rtlcl~e u~ed at the oepar-tloD ~ethod ; ccordlng to the inventlon can b re~od ~oy tl~eo ~orreepon-tlng technlqueo ~a~ be ~eot ao ln connection vlth convent~onnl ~i llquld chro~tography ~or ~r-olD~ ~hc p~rtlelec froo oubot-ncee lS h-vlng bcon bound to the partlcl~- durlng ooparatlon proce~.
She p rtlcle ~lze ~hould b- a- 04~11 ae po~lble but ha- to be d-ptod to the cho-en co~bln~tlon of tho accoopll-hed contrl-~o~al forc- nd tho ~gnltude of the ISqlsd ~lo~ ln the ccntrl-_..
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20~Z835 fugal field ln question. Preferably, particles in the magnitudeof 0,1 - 10 ~m are used.
The invention is described in the followlng wity reference to the accompanying drawing. In the drawing fig 1 shows schemati-cally a so called open centrifuge rotor of a ki ~ that can be used upon application of the invention. Fig 2 6hows a pa~ of ; the centrifuge rotor in fig 1 somewhat modified. Fig 3/shows a so called closed centrifuge rotor that alternatively can be used upon application of the invention.
Fig 1 shows a part of a centrifuge rotor comprising a rotor body 1 supported by a vertical drive shaft 2. The rotor body 1 defines a separation chamber 3, in which a stack of conven-tional frusto-conical separation discs 4 18 arranged coaxially with the rotor. The stack of separation discs 4, which have ,~
axially aligned 80 called tistributing holes 5, rests upon a ~-conical bottom plate 6. This plate has corresponding holes 7 aligned with the tistributing holes 5. The bottom plate 6 forms ~ 20 together with the lower part of the rotor body 1 a chamber 8 ¦ which communicates with the separation chamber 3 through the hole~ 7 in the bottom plate 6. A channel 9 extending axially through the drive shaft 2 opens into the cha~ber 8.
;~ 25 A conical partitlon 10 delimiting together with the upper part of the rotor body 1 a number of channels ll rests upon the stack of separation discs 4. The channels 11 extend from a radially outer part of the separatlon chamber 3 towards the centre of the rotor and open in a first outlet chamber 12 formed by the radially inner parts of the rotor body 1 and the partition 10, respectively.
Radially inside the first outlet chamber 12 the radially inner part of the partition 10 forms a second outlet chamber 13. The separation chamber 3 communicates through an overflow outlet 14 ; with said second outlet chamber 13.
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~002835 Both of the outlet chambers 12 and 13 are formed as radially inwardly open annular groves, and lnto these groves there extend stationary outlet members 15 and 16, respectively, which nay have the form of conventional 80 called paring discs. Both of the outlet members are supported by a stationary inlet pipe 17 extendlng from the outside of the rotor into a central inlet chamber 18 in the rotor, formed radially inside the frusto-conical separation discs 4. The part of the inlet pipe 17 that is situated in the inlet chamber 18 is perforated, 80 that a liquid supplied through the inlet pipe may be sprayed radially outwardly and be distributed along the axial extension of the inlet chamber.
At the radially outermost part of the separation chamber 3 the rotor body 1 has a number of outlet openings 19 evenly distri-buted around the rotor axis. In a manner known per se these outlet openings may be arranged to be opened and closed during operation of the rotor.
During operation the above described centrifuge rotor will contain both llquid and very small particles having a density less than that of the liquid. The liquid will form a rotating body filllng the largest part of the separation chamber 3 comprlslng the spaces between the 8eparatlon discs 4 and part of the central inlet chamber 18, and the particles will be su8pended ln a cyllndrlcal sleeve formed layer 20 of the liquid body sltuated close8t to the rotor axls. The layer 20 extends radlally inwardly to the level of the overflow outlet 14, where-by llquld supplled to the rotor through the lnlet plpe 17 wlll be sprayet agalnst the lnslde of the layer 20. The layer 20 may be dlvided in separate sectors by means of radially and axlally extending entrainment wings (not shown) supported radlally lnside the separatlon dlscs 4 by the bottom plate 6 and the partltlon 10.
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~he centrifuge rotor in fig 1 is intended to operate in the following manner.
Liquid from which a certain substance is to be separated is supplied through the inlet pipe 17 and is sprayed towards the inside of the rotating sleeve formed liquid layer 20 containing particles. By this liquid supply the particles will be main-tained in a suspended state in the rotating liquid body. The larger the liquid supply through the inlet pipe 17 is made, the larger distance will be obtained between the particles in the liquid body.
During the passage of the supplied liquid through the layer 20 it is brought into effective contact with the particle surfaces which are prepared in a known manner to attract the substance to be separated from the liquid. When the liquid has passed through the layer 20 and been freed from all or part of said ~ubstance, it flows further on radially outwardly through the spaces between the separation discs 4 to the radially outer part of the separation chamber 3. From there the liquid flows through the channels 11 radially inwartly to the outlet chamber 12, from where lt i8 removed by means of the stationary outlet member 15.
During the separating operation described above new particles may be supplied to the rotor and used particles may be removed from the rotor either continuously or intermittently. New particles can be supplied through the channel 9 in the drive shaft 2 and, through the chamber 8 and the distributing holes 5, be pumped into the spaces between the separation discs 4.
Supplied new particles will thus move countercurrently relative to the liquid flowing radially outwardly in the rotor. Hereby, a corresponding s~ount of particles having separated the above mentioned substance from the supplied liquid is displaced out of the inlet chamber 18 through the overflow outlet 14 to the outlet chamber 13. By means of the stationary outlet member 16 the particles are removed from the outlet chamber 13.
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Accordlng to an alternative way of intermittently displacing particles out of the separatlon chamber 3 the outflow of llquld through the 6tatlonary outlet member 15 may be lnterrupted temporarily, while new liquid contlnuously is supplied through S the lnlet plpe 17. Then, the liquld ~urfaces ln both the outlet chamber 12 and the separatlon chamber 3 (or the lnlet cha~ber 18) wlll move radlally lnwardly.
New partlcles are preferably supplied to the centrifuge rotor suspended in a llquid of a suitable kind, for instance a part of the liquid having left the centrifuge rotor after having been freed from the above said substance. In a known manner particles having been used ln the descrlbed separatlng operation, l.e.
having been discharged from the centrifuge rotor through the outlet chamber 13, may be reconditioned and be used anew. Upon need the particle suspenslon supplied to the rotor through the channel 9 may be more tiluted, i.e. contain less particles per unit of volume of the particle suspension, than the particle suspension discharged from the rotor by means of the outlet member 16. The composition of the discharged particle suspension is determined by the particle density that is used in the layer 20 of partlcles fluidized ln liquid.
By use of conical separation discs 4 of the described kind particles havlng for its ob~ect to attract the said substance in the supplied llquid may be effectlvely prevented from belng entrained by liquit too far on lts way radially outwartly in the rotor. However, it may be sultable to dimension the separation dlscs in a way such that a large part of the particle suspension is formed radlally inside the separation discs in order to avoid that the particle suspension will become too dense.
It has been assumed above that the centrifuge rotor has a separate inlet for new particles. Alternatively, new particles may be supplied to the centrifuge rotor through its ordinary . ` . -''' " ' ' . - ' . .
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20~)2~335 inlet for the said liquid, i.e. they may be mixed with the liquid before it ls supplied to the centrifuge rotor. Fig 2 shows an embodiment of a centrifuge rotor arranged for supply of new particles in this way.
Fig 2 shows a perforated inlet pipe 17a supporting an outlet member 16a. The outlet member extends radially outwards in an outlet chamber 13a, which through a number of holes 21 in a partition 22 communicates with the separation chamber of the rotor. The holes 21 are placed at a level radially outsite the free liquid surface formed in the inlet chamber lôa by the liquid body rotating therein.
In the ratially innermost layer of the liquid body, which layer ls designated 20a in fig 2, the particles are maintainet in a suspentet state by supply of liquit through the perforatet inlet pipe 17a. As can be seen, the partition 22 extends radially inwartly to a level insite the layer 20a, so that the particle suspension cannot flow into the outlet chamber 13a any other way than through the holes 21. These are situated at the level of the ratially outer part of the layer 20a.
In the embodiment shown in fig 2 the centrifuge rotor has frusto-conical separation tiscs 4a, which at their radially 2S innermost edges support annular members 23 extending substan-tially horlzontally. The members 23 have a ratially outwartly increasing thickness, whereby the interspaces between them converge ratially outwartly. This is a design of the members 23 enabling that a substantially unchanget or even tecreasing throughflow section may be provided for liquid flowing radially outwardly through the layer 20a of the particle suspension.
The members 23 have holes 24 axially aligned with each other and with the holes 21, whereby particles having separated a certain substance from the passing liquit may leave the layer 20a at the - .. ;~ . .: ~
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actual radial level and flow out lnto the outlet chamber 13a.
Thereln, if desired, a free liquid surface may be maintained by means of the outlet member 16a radlally outside the free llquid surface ln the inlet chamber 18a. It ls presumed that the holes 21 form a throttle for the flow of suspension out lnto the outlet chamber 13a.
In an embodlment of the centrlfuge rotor according to fig 2 new particles preferably are supplled to the layer 20a together with the liquid supplied through the lnlet plpe 17a. Thls enables the new particles at the beginning to be kept su6pended in the radially innermost part of the layer 20a and - as they gradually separate said 6ubstance from the llquld and thereby in certaln appllcations of the lnventlon get heavier - to move rsdlally outwardly and finally leave the layer 20a through the holes 24 and 21.
Fig 3 shows an alternatlve embodiment of a centrifuge rotor by means of which the method according to the invention may be performed. Parts of the centrlfuge rotor in fig 3 corresponding to parts of the centrifuge rotor in fig 1 have the same refe-rence numerals as the latter with the adtition of a letter b.
The centrlfuge rotor in flg 3 has an inlet pipe 25 for liquit from which a substance is to be separated, extending into the rotor through the channel 9b in the drive shaft 2b. The inlet pipe 25, that i8 rotatable together with the rotor, is per-forated along its extension in the inlet chamber 18b.
The rotor body lb supports at it~ upper part a pipe 26 and a pumping wheel 27 connected with the pipe. The pipe 26 and the pumplng wheel 27 are surrounded ~ealingly by a statlonary pumplng house 28 having an outlet conduit 29. The interior of the pipe 26 communlcates with the channels 11b ln the rotor and with the interior of the pumping wheel 27, whereby the latter is .,,.~.. . , . - . , :. ~: ' ' . ' -- ' .
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200~83s arranged to pump llquid from the separation chamber 3b through the channels 11b out into the pumping housing 28 and further through the outlet conduit 29.
In a similar manner the conical partition lOb at its upper part ls connected with a plpe 30, which extends coaxially through the pipe 26, and supports a pumping wheel ~1. The upper part of the pipe 30 and the pumping wheel 31 are surrounded sealingly by a stationary pumping housing 32 having an outlet conduit 33. The interior of the pipe 30 communicates with the inlet chamber 18b and with the interior of the pumping wheel 31, whereby the latter is arranged to pump particle suspension from the inlet chamber 18b out into the pumping housing 32 and further through the outlet conduit 33.
A centrifuge rotor according to fig 3 operates in substantially the same manner as a centrifuge rotor according to fig 1. The only difference is that the whole inlet chamber 18b is filled with particle suspension during operation and that the separa-ting operation within the rotor may be perfored at a super-atmospheric pressure and without the liquid and particles coming into contact with the atmosphere surrounding the rotor.
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15 Separation by means of so called liquid chromatography tradi-tionally means that a liquid, from which a substance is to be separated, is caused to pass through a treatment chamber filled with a lot of small particles retained closely packed together in the treatment chamber between two perforated end walls. The ~ 20 liquid thus has to flow through the interspaces between the J, immobilized particles, the substance to be separated being retained by means of the particles by adsorption at their 8urfaces or in some other way.
25 A problem in connection with this separation technique is that the flow resistance for the liquid is very large in the inter-spaces between the particles. The smaller the particles are, the larger this flow resistance will be. The liquid thus has to be highly pre6surized to be able to pass through the interspaçes ~ 30 between the particles. The problem is accentuated by the fact 3 that the particles preferably are made as small as possible, since a certain volume of packet particles exposes a larger total particle surface to a through-flowing liquid the smaller ~ the particles.
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--` Z~)02835 For ~hese reasons it ls difflcult to provide for acceptable costs a separation plant having a large separation capacity, and the described separation technique, therefore, is mainly utillzed in a small scale, e.g. for analysing purposes or for the separation of very small amounts of very expensive substances.
As an alternative to the above described separation technique it has been suggested that a liquid, from which a substance is to be separated, be supplied to the lower part of a treat-ment chamber containing a bed of particles, which are free~to move relative to each other, and then be caused to flow through the bed of particles from below , upwardly in a way such that the particles are maintained in a fluidized or suspended state within the treatment chamber.
A fluidizing technique of this kint would require a smaller overpressure of the supplied liquid than the previously described separation technique. However, the capacity of a separation plant in this case woult instead be limited by the I fact that the flow velocity of the liquid through the bed of ¦ particles could not be too large. This flow velocity must not ¦ be larger than that required to retain the particles in the bed by gravity and not b~ elltrained by th~ ~pwaraly flow~ing liquid and thereb~ carried out of the treatment chamber.
One further technique suggested to bind a certain subtance in a liquid to particles resides in keeping the particles suspended in the liquid by agitation for some time ant then - after the particles have attracted the said substance in the liquid - separating the particles from the liquid by gravity separation or centrifugal force separation. A disadvan-tage of this technique is that it will take a relatively long time to create the required contact between the particles and ~ 35 all parts of the liquid for the separation of the substance i therein-~, .
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;~ 0 0 2 8 3 5 The present invention provides a new method of sep&rating a substance from liquid by blnding the substance to small partLcles, which method makes it possible to obtain a substantially larger separation capaclty than the 5 above described methods and, thus, can be used in a much larger scale than these methods. The invention also enables the use of substantially smaller pa~ticles than could be used ln the prior art.
10 These results are obtained according to the invention by keeping a body of liquid having a predetermined density in rotation together with small particles having a density lower than that of the liquid, and by bringing liquid, from which said 3 substance is to be separated, into contact with the particles in 15 a way s~ch that the particles are maintained suspended in the rotating liquid.
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The invention consequently resides in keeping particles lighter than a liquid in a suspended state in a rotating liquid body, 20 while the liquid, from which a substance is to be separated, is caused to flow past the suspendet particles.
'~ If desired, the partlcles may be kept suspended in the whole of~, the rotatlng llquld body. Preferably, however, the partlcles are 25 kept suspended only in a layer of the liquid body, the liquid to ~ be freed from said substance being caused to flow through the q suspensi~n layer. The main part of the liquid should flow bet-ween the suspended particles in a directi,Qn from the rotational ;j axis of the rotatlng liquld body outwardly towards the radially~ 30 outermost part of the liquid body.
.. . .
~ Slnce the particles are lighter than the llquld, the particles ; suspendet in the liquid will try,due to the centrifugel force,to ;~ move radially inwards, the force influencing the particles in ~ 35 this direction being larger the furtherfrom the rotational axis :~;, ,. ; , . -:~......... ; , : ., .
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the particles are situated. Therefore, the supply of liquld from which said substance ls to be separated may be made very large without any risk that the particles should leave the treatment chamber together with radially outwardly flowing liquid. The force to which the particles are sub~ected by the flow of the supplied liquid is independent of the distance between the ; particles and the rotational axis.
If the particle size would vary somewhat in the suspension layer, this does not matter very much, since extremely small particles which are easily entrained by the supplied liquid will still be retained in the vicinity of the other particles as a consequence of the radially outwardly increasing centrifugal force. By the same mechanism a particle is immediately returned ratially inwardly, if it has been influenced by occasional forces and been transferred too far out from the rotational axis.
The liquid body kept in rotation may have any desired shape.
If it has a shape such that the through-flow ~ection for the supplied liquid increases radially outwardly, the balanclng effect on the suspended particles will be even larger, since the force acting on the particles and caused by the flow of the liquid in this case decreases with increasing distance from the rotational axis of the liquid body, whereas the centrifugal force, acting in the opposite direction, increases.
An increasing through-flow section for the supplied liquid may be desirable, particularly in the radially outer part of the-suspension layer, for safe retainment of the particles therein.In the main part of the suspension layer it may be desirable, however, to have instead a radially outwardly decreasing through-flow section for the supplied liquid. Thereby, namely, it may be accomplished if desired a substantially uniform distribution of the particles in the suspension layer along the .~ . . - . , .
flov path ofthe llquld thercthrough If the partlcle~ h~ve -cert~n ~lze dl~trlbutlon, tbld haJ to bs conrldered ln connectlon wlth the p1~ning of tbe flo~ path of the liquid throu~h the 4u~pen~10n l~yer or e~tabllRhIn2 ~ de~lrea dl-trlbutlo~ o~ the partlcle~ ther~ln ould be ob~lou~, ~ny deslr~d di~tance botween the psrticl--in the ~u8pe~100 layer ~J b- cco~pll~hed b~ ~ ~ult~bl~ cholcc of centrlfug~l force ~ehlD 8~t llquld flow through the ~u~p~n-~lon lAyer ~hl~ tlst~nce mAy ~ou bc chnng~d by controlllng ofthe cenerlfu~al ~orce ~nt/or the llqult flo~ durlng the co~r~o of the ~cpArntlon procs~-If tesired, lt 18 po~s~ble by uoln~ p8rtlcle~ of dlfferent ~l~es to obtcln dlfferent (oep8rste or overl-pplng) l-~er~ of ~urpen-ted psrtlc1-~ ln the rotatlng llquld body. ~ could be 8~ful ln conne~tlon wlth b~tch-~ise u~e of partlcla~ durlng a ~cp-r-~
i tlng operselon 1~ order to ll~lt the r-dl-l ~ove~ent of tb~
particlo~ wlthln the ~uspenslon l-yer of the rot~tlng llquld boty Atv~nt~$oou-ly, o con~8ntloo-1 c-ntrli'~g~ p r-tor bal~ only ln~lgnlflc-ntl~ ~odl~l~d -~ bc ~ed for eh~ p~rfor~ln~ of the cthod ~ccordln~ to th~ ln~entloo~ both oald llquld ~nd tbe p rtlcles belng kept ln rot-t~oo 1~ the i~or~ of ~ ub~t~ntlelly ~nnul~r body Th~ lo~entlon ~ay be u~ed lo coonoctlo~ wlth ubst~ntl~
ep-r-tion proce~e~ of ~ klnd ln ~hlch coo~ntlon-l liqu~d cbrc~tography could co~e ~nto qu-rtloa Furth-r~ore, the lnventlon ~ke~ lt po~lble by ee-~ of th~ ~epar-tLon technlqu-her~ ln qu&~tlon to re~olve - y cp-r-tlon problemJ ~hlch at pre-enc cannot b~ recol~ed ln ~ econo~Lcall~ ccept-ble vCg Thu~, the ln~ntlon nake- lt por~ble ~n an lndu~trlal ~c-l~ to ~parate ~ery ~all ~ount~ of ~clu~blQ or hA~mful ~ub~tance~
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fr~ l~r~e ~ount~ of hesvlly t~lut-t ~olut~on- ~or IQ~t~nc~, th- lnvent~on ~y b- u-ed for ~xtr~ctln~ v-l~ blc net~ uch s p ld nd ~llvor, fro~ ~olutlon~, or ~or ostr-ctSng proteln-, polypoptlde~ or a~lno~cld- fro~ blotechnlcal proce-- llquld~.
Al~o c-rbohy~rate~ snd llplde~ ccn be extracted. Furtber-ore, the qu-l~ty of cort-ln trln~r, uch 4 be~r or ~lne, ~ay be l~proved by re~oval of cert~ ubat-nce~. Another o~
th-t wa~te ~ater nay be purlfl~t fro~ uod-Rlrod ~ub-t~nce~, ~uch a~ heavy ~etal~, phenole- or cy-nldo, befor~ lt 1~ du~ped 1~ ehe n-ture :.
The cholce of ~Aterl~l foe the p-rtlc~-~ to ~e u~ed ~c~ to b~
c~de wlth reg-rd to tho llqu~d ~ro~ ~hlch a ~ub~tance ~hould be ~ep~rat~d and to ~ald ~ub-tanc~. Slnc- ~Ang proces~ llquld- h-vo 15 a tens~ey of about 1,0 g/c 3. p~rticloc h-vl~ d-n~ley low-lr than 1,0 g/c~3 often have to bn ¢h4~0n. Then, dlffer-nt ~l~dr of pla~tlc ~terl~ y co C icto que~tlon. rOr ln~tcnce pol~-- ethene or polypropene ~sy be u~ed A~ a b sic o terl-l ln tho partlclc~. ~o~Qver, ~at-rl-l ha-vler th-n 1,0 g/c~3 ~y b-20 u~e,ll, if partlcl~ of l~uch -terl-l re e~pJInte,a by ~e-n- of pre~iou-ly known t-chn1qu~, c~h th~t they wlll conteln a Sac ol on- ~lnt or Aaother P~rtlcl-c of thl- ~lnd bc~g de7~clt~ e-lo~ ~ 0~04 s/c~3 ra A-~ll-bl~ on thc u-rktt.
25 I7~ th- a~o- u~nn-r ~ n-r~lly bno~n In connectlon ~lth con~cAtlo?~al llqult chro~to~raph~ tho p FtlCl~ to bc u-ed for th~ m~thod cccordln~ eo th- Inv ntlo~ aors-ll~ h-vc to S~
pr-p ect cuCh th t they ca~ attr-ct or b~nd a cubstc~c- to bc ~e?p r-tod froo llquld. In on~ v~ or ~noth-r - of c~vcral 30 ~no~n ~ay- - t~c p~rtlcle- r- glv~n ?~ ctl~e ~urÇ-c~ ~bleh ` for ln-t-nce chc~lc-lly or ph~lccll~ olnd -~d ~bc~ancc i to ehe p-rtlclec, ~hen llquld ~at~ l~to cont~ct there~lth, ~or ? ln~t-ncc, lt 1- po--lbl- to ~1~ th- p~rtlcl~ urf-ce- c-rt d n`? chJrRln~, ~0 th-t th-~ c n tt~ ct nd blnd p~rtlcul-tc ~ub-t-n-35 c~ h~ln~ thc oppo-lta ch rslns ~lon e~chc~ge technlqu-). E~e ,~
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6 a ~ell known pr~ncl~loo ~or oo cnll~t fflnl q -chrooatoaraph~, hydrofob~c lnter~ctlon, tc , ~Ay b~ uuod ln connectlon wlth the pre~ont lnventlon~
It 1~ o po~lble to uoe p~rtlcl~- hevlng the blllty of ab-orblng a ~ub~t-nce ln llq~ld. In euch c~eo~ the aubst-nce penetr~tes lnto th- p rtlclo body ln quo~tlon, ~her- lt 1 reta~ned~
AA ln connectlon wlth conventlonal llq~ld chro~ tography lt 1-often de~lred that the p-rtlcl~e u~ed at the oepar-tloD ~ethod ; ccordlng to the inventlon can b re~od ~oy tl~eo ~orreepon-tlng technlqueo ~a~ be ~eot ao ln connection vlth convent~onnl ~i llquld chro~tography ~or ~r-olD~ ~hc p~rtlelec froo oubot-ncee lS h-vlng bcon bound to the partlcl~- durlng ooparatlon proce~.
She p rtlcle ~lze ~hould b- a- 04~11 ae po~lble but ha- to be d-ptod to the cho-en co~bln~tlon of tho accoopll-hed contrl-~o~al forc- nd tho ~gnltude of the ISqlsd ~lo~ ln the ccntrl-_..
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20~Z835 fugal field ln question. Preferably, particles in the magnitudeof 0,1 - 10 ~m are used.
The invention is described in the followlng wity reference to the accompanying drawing. In the drawing fig 1 shows schemati-cally a so called open centrifuge rotor of a ki ~ that can be used upon application of the invention. Fig 2 6hows a pa~ of ; the centrifuge rotor in fig 1 somewhat modified. Fig 3/shows a so called closed centrifuge rotor that alternatively can be used upon application of the invention.
Fig 1 shows a part of a centrifuge rotor comprising a rotor body 1 supported by a vertical drive shaft 2. The rotor body 1 defines a separation chamber 3, in which a stack of conven-tional frusto-conical separation discs 4 18 arranged coaxially with the rotor. The stack of separation discs 4, which have ,~
axially aligned 80 called tistributing holes 5, rests upon a ~-conical bottom plate 6. This plate has corresponding holes 7 aligned with the tistributing holes 5. The bottom plate 6 forms ~ 20 together with the lower part of the rotor body 1 a chamber 8 ¦ which communicates with the separation chamber 3 through the hole~ 7 in the bottom plate 6. A channel 9 extending axially through the drive shaft 2 opens into the cha~ber 8.
;~ 25 A conical partitlon 10 delimiting together with the upper part of the rotor body 1 a number of channels ll rests upon the stack of separation discs 4. The channels 11 extend from a radially outer part of the separatlon chamber 3 towards the centre of the rotor and open in a first outlet chamber 12 formed by the radially inner parts of the rotor body 1 and the partition 10, respectively.
Radially inside the first outlet chamber 12 the radially inner part of the partition 10 forms a second outlet chamber 13. The separation chamber 3 communicates through an overflow outlet 14 ; with said second outlet chamber 13.
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~002835 Both of the outlet chambers 12 and 13 are formed as radially inwardly open annular groves, and lnto these groves there extend stationary outlet members 15 and 16, respectively, which nay have the form of conventional 80 called paring discs. Both of the outlet members are supported by a stationary inlet pipe 17 extendlng from the outside of the rotor into a central inlet chamber 18 in the rotor, formed radially inside the frusto-conical separation discs 4. The part of the inlet pipe 17 that is situated in the inlet chamber 18 is perforated, 80 that a liquid supplied through the inlet pipe may be sprayed radially outwardly and be distributed along the axial extension of the inlet chamber.
At the radially outermost part of the separation chamber 3 the rotor body 1 has a number of outlet openings 19 evenly distri-buted around the rotor axis. In a manner known per se these outlet openings may be arranged to be opened and closed during operation of the rotor.
During operation the above described centrifuge rotor will contain both llquid and very small particles having a density less than that of the liquid. The liquid will form a rotating body filllng the largest part of the separation chamber 3 comprlslng the spaces between the 8eparatlon discs 4 and part of the central inlet chamber 18, and the particles will be su8pended ln a cyllndrlcal sleeve formed layer 20 of the liquid body sltuated close8t to the rotor axls. The layer 20 extends radlally inwardly to the level of the overflow outlet 14, where-by llquld supplled to the rotor through the lnlet plpe 17 wlll be sprayet agalnst the lnslde of the layer 20. The layer 20 may be dlvided in separate sectors by means of radially and axlally extending entrainment wings (not shown) supported radlally lnside the separatlon dlscs 4 by the bottom plate 6 and the partltlon 10.
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~he centrifuge rotor in fig 1 is intended to operate in the following manner.
Liquid from which a certain substance is to be separated is supplied through the inlet pipe 17 and is sprayed towards the inside of the rotating sleeve formed liquid layer 20 containing particles. By this liquid supply the particles will be main-tained in a suspended state in the rotating liquid body. The larger the liquid supply through the inlet pipe 17 is made, the larger distance will be obtained between the particles in the liquid body.
During the passage of the supplied liquid through the layer 20 it is brought into effective contact with the particle surfaces which are prepared in a known manner to attract the substance to be separated from the liquid. When the liquid has passed through the layer 20 and been freed from all or part of said ~ubstance, it flows further on radially outwardly through the spaces between the separation discs 4 to the radially outer part of the separation chamber 3. From there the liquid flows through the channels 11 radially inwartly to the outlet chamber 12, from where lt i8 removed by means of the stationary outlet member 15.
During the separating operation described above new particles may be supplied to the rotor and used particles may be removed from the rotor either continuously or intermittently. New particles can be supplied through the channel 9 in the drive shaft 2 and, through the chamber 8 and the distributing holes 5, be pumped into the spaces between the separation discs 4.
Supplied new particles will thus move countercurrently relative to the liquid flowing radially outwardly in the rotor. Hereby, a corresponding s~ount of particles having separated the above mentioned substance from the supplied liquid is displaced out of the inlet chamber 18 through the overflow outlet 14 to the outlet chamber 13. By means of the stationary outlet member 16 the particles are removed from the outlet chamber 13.
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Accordlng to an alternative way of intermittently displacing particles out of the separatlon chamber 3 the outflow of llquld through the 6tatlonary outlet member 15 may be lnterrupted temporarily, while new liquid contlnuously is supplied through S the lnlet plpe 17. Then, the liquld ~urfaces ln both the outlet chamber 12 and the separatlon chamber 3 (or the lnlet cha~ber 18) wlll move radlally lnwardly.
New partlcles are preferably supplied to the centrifuge rotor suspended in a llquid of a suitable kind, for instance a part of the liquid having left the centrifuge rotor after having been freed from the above said substance. In a known manner particles having been used ln the descrlbed separatlng operation, l.e.
having been discharged from the centrifuge rotor through the outlet chamber 13, may be reconditioned and be used anew. Upon need the particle suspenslon supplied to the rotor through the channel 9 may be more tiluted, i.e. contain less particles per unit of volume of the particle suspension, than the particle suspension discharged from the rotor by means of the outlet member 16. The composition of the discharged particle suspension is determined by the particle density that is used in the layer 20 of partlcles fluidized ln liquid.
By use of conical separation discs 4 of the described kind particles havlng for its ob~ect to attract the said substance in the supplied llquid may be effectlvely prevented from belng entrained by liquit too far on lts way radially outwartly in the rotor. However, it may be sultable to dimension the separation dlscs in a way such that a large part of the particle suspension is formed radlally inside the separation discs in order to avoid that the particle suspension will become too dense.
It has been assumed above that the centrifuge rotor has a separate inlet for new particles. Alternatively, new particles may be supplied to the centrifuge rotor through its ordinary . ` . -''' " ' ' . - ' . .
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20~)2~335 inlet for the said liquid, i.e. they may be mixed with the liquid before it ls supplied to the centrifuge rotor. Fig 2 shows an embodiment of a centrifuge rotor arranged for supply of new particles in this way.
Fig 2 shows a perforated inlet pipe 17a supporting an outlet member 16a. The outlet member extends radially outwards in an outlet chamber 13a, which through a number of holes 21 in a partition 22 communicates with the separation chamber of the rotor. The holes 21 are placed at a level radially outsite the free liquid surface formed in the inlet chamber lôa by the liquid body rotating therein.
In the ratially innermost layer of the liquid body, which layer ls designated 20a in fig 2, the particles are maintainet in a suspentet state by supply of liquit through the perforatet inlet pipe 17a. As can be seen, the partition 22 extends radially inwartly to a level insite the layer 20a, so that the particle suspension cannot flow into the outlet chamber 13a any other way than through the holes 21. These are situated at the level of the ratially outer part of the layer 20a.
In the embodiment shown in fig 2 the centrifuge rotor has frusto-conical separation tiscs 4a, which at their radially 2S innermost edges support annular members 23 extending substan-tially horlzontally. The members 23 have a ratially outwartly increasing thickness, whereby the interspaces between them converge ratially outwartly. This is a design of the members 23 enabling that a substantially unchanget or even tecreasing throughflow section may be provided for liquid flowing radially outwardly through the layer 20a of the particle suspension.
The members 23 have holes 24 axially aligned with each other and with the holes 21, whereby particles having separated a certain substance from the passing liquit may leave the layer 20a at the - .. ;~ . .: ~
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actual radial level and flow out lnto the outlet chamber 13a.
Thereln, if desired, a free liquid surface may be maintained by means of the outlet member 16a radlally outside the free llquid surface ln the inlet chamber 18a. It ls presumed that the holes 21 form a throttle for the flow of suspension out lnto the outlet chamber 13a.
In an embodlment of the centrlfuge rotor according to fig 2 new particles preferably are supplled to the layer 20a together with the liquid supplied through the lnlet plpe 17a. Thls enables the new particles at the beginning to be kept su6pended in the radially innermost part of the layer 20a and - as they gradually separate said 6ubstance from the llquld and thereby in certaln appllcations of the lnventlon get heavier - to move rsdlally outwardly and finally leave the layer 20a through the holes 24 and 21.
Fig 3 shows an alternatlve embodiment of a centrifuge rotor by means of which the method according to the invention may be performed. Parts of the centrlfuge rotor in fig 3 corresponding to parts of the centrifuge rotor in fig 1 have the same refe-rence numerals as the latter with the adtition of a letter b.
The centrlfuge rotor in flg 3 has an inlet pipe 25 for liquit from which a substance is to be separated, extending into the rotor through the channel 9b in the drive shaft 2b. The inlet pipe 25, that i8 rotatable together with the rotor, is per-forated along its extension in the inlet chamber 18b.
The rotor body lb supports at it~ upper part a pipe 26 and a pumping wheel 27 connected with the pipe. The pipe 26 and the pumplng wheel 27 are surrounded ~ealingly by a statlonary pumplng house 28 having an outlet conduit 29. The interior of the pipe 26 communlcates with the channels 11b ln the rotor and with the interior of the pumping wheel 27, whereby the latter is .,,.~.. . , . - . , :. ~: ' ' . ' -- ' .
.
200~83s arranged to pump llquid from the separation chamber 3b through the channels 11b out into the pumping housing 28 and further through the outlet conduit 29.
In a similar manner the conical partition lOb at its upper part ls connected with a plpe 30, which extends coaxially through the pipe 26, and supports a pumping wheel ~1. The upper part of the pipe 30 and the pumping wheel 31 are surrounded sealingly by a stationary pumping housing 32 having an outlet conduit 33. The interior of the pipe 30 communicates with the inlet chamber 18b and with the interior of the pumping wheel 31, whereby the latter is arranged to pump particle suspension from the inlet chamber 18b out into the pumping housing 32 and further through the outlet conduit 33.
A centrifuge rotor according to fig 3 operates in substantially the same manner as a centrifuge rotor according to fig 1. The only difference is that the whole inlet chamber 18b is filled with particle suspension during operation and that the separa-ting operation within the rotor may be perfored at a super-atmospheric pressure and without the liquid and particles coming into contact with the atmosphere surrounding the rotor.
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Claims (10)
1. Method of separating a substance from a liquid by binding the substance to the particles, c h a r a c t e r i z e d i n that a body of liquid having a predetermined density is kept in rotation together with small particles having a density lower than that of the liquid, and that liquid from which said substance is to be separated is brought into contact with the particles in a way such that these are maintained suspended in the rotating liquid body.
2. Method according to claim 1, c h a r a c t e r i z e d i n that the main part of the liquid from which said substance is to be separated is caused to flow between the suspended particles in a direction from the rotational axis of the rota-ting liquid body towards the radially outer part of the liquid body.
3. Method according to claim 1 or 2, c h a r a c t e r i -z e d i n that the liquid from which said substance is to be separated is caused to flow through a layer (20) of the rotating liquid body, in which the particles are maintained suspended.
4. Method according to claim 3, c h a r a c t e r i z e d i n that liquid is continuously removed from the radially outer part of the said layer (20).
5. Method according to any of the preceding claims, c h a -r a c t e r i z e d i n that new particles are supplied and used particles are removed from the liquid body, while this is kept in rotation.
6. Method according to any of the preceding claims, c h a -r a c t e r i z e d i n that the liquid body and the particles are kept in rotation as a substantially annular body.
7. Method according to any of the preceding claims, c h a -r a c t e r i z e d i n that liquid is conducted from the rotating liquid body radially outside the suspended particles to a space (12), in which it is allowed while being rotated to form a free, preferably annular, liquid surface which is maintained at a predetermined radial level.
8. Method according to any of the preceding claims, c h a -r a c t e r 1 z e d i n that a free surface of the rotating body of liquid and particles is maintained at a predetermined level in a chamber (3), that is delimited by a rotating body (1), by means of an overflow outlet (14) from said chamber (3).
9. Method according to any of claims 3-7, c h a r a c -t e r i z e d i n that new particles are supplied to said layer (20a) of the rotating liquid body at a first level and that used particles are removed from the layer (20a) at a second level (21) radially outside said first level.
10. Method according to any of the preceding claims, c h a -r a c t e r i z e d i n that the liquid from which said substance is to be separated is caused to flow past the suspen-ded particles along a flow way, the through-flow section of which decreases and in which the centrifugal force increases, seen in the direction of flow of the liquid.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE8804141A SE465604B (en) | 1988-11-16 | 1988-11-16 | SET FOR SEPARATION OF A SUBJECT FROM A SCIENTIFIC WITH THE PARTICULAR MATERIAL |
| SE8804141-3 | 1988-11-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2002835A1 true CA2002835A1 (en) | 1990-05-16 |
Family
ID=20373961
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2002835 Abandoned CA2002835A1 (en) | 1988-11-16 | 1989-11-14 | Method of separating a substance from a liquid by means of a particulate material |
Country Status (9)
| Country | Link |
|---|---|
| EP (1) | EP0444070A1 (en) |
| JP (1) | JPH04501679A (en) |
| CN (1) | CN1043883A (en) |
| AU (1) | AU4507389A (en) |
| BR (1) | BR8907773A (en) |
| CA (1) | CA2002835A1 (en) |
| DK (1) | DK91591A (en) |
| SE (1) | SE465604B (en) |
| WO (1) | WO1990005572A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CZ148593A3 (en) * | 1991-01-25 | 1994-01-19 | Novo Nordisk As | Process of separating a non-dissolved catalyst from one or a plurality of other non-dissolved components comprised in the same reaction mixture |
| US5186824A (en) * | 1991-09-04 | 1993-02-16 | Large Scale Biology Corporation | System for solid phase reactions |
| US6942804B2 (en) | 2001-11-09 | 2005-09-13 | Kinetic Biosystems, Inc. | Methods and compositions for chromatography |
| DE102010023130B4 (en) * | 2010-06-09 | 2012-04-12 | Basf Se | Wanderfeldreaktor and method for separating magnetizable particles from a liquid |
| BR112013001049A2 (en) * | 2010-07-15 | 2016-05-24 | Hoeganaes Ab Publ | copper iron fluid purification compositions |
| EP2944391A1 (en) * | 2014-05-13 | 2015-11-18 | Alfa Laval Corporate AB | Centrifugal separator |
| DE102018131956A1 (en) * | 2018-12-12 | 2020-06-18 | Gea Mechanical Equipment Gmbh | Separator and method for its operation |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4650575A (en) * | 1985-07-03 | 1987-03-17 | Pall Corporation | Sorbing apparatus |
| US4775484A (en) * | 1987-03-09 | 1988-10-04 | Life Systems, Inc. | Method and apparatus for the continuous separation of contaminants from a fluid mixture |
-
1988
- 1988-11-16 SE SE8804141A patent/SE465604B/en not_active IP Right Cessation
-
1989
- 1989-11-09 AU AU45073/89A patent/AU4507389A/en not_active Abandoned
- 1989-11-09 JP JP51152789A patent/JPH04501679A/en active Pending
- 1989-11-09 EP EP19890912512 patent/EP0444070A1/en not_active Withdrawn
- 1989-11-09 BR BR898907773A patent/BR8907773A/en unknown
- 1989-11-09 WO PCT/SE1989/000638 patent/WO1990005572A1/en not_active Application Discontinuation
- 1989-11-14 CA CA 2002835 patent/CA2002835A1/en not_active Abandoned
- 1989-11-16 CN CN 89109268 patent/CN1043883A/en active Pending
-
1991
- 1991-05-15 DK DK091591A patent/DK91591A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| CN1043883A (en) | 1990-07-18 |
| EP0444070A1 (en) | 1991-09-04 |
| SE8804141D0 (en) | 1988-11-16 |
| BR8907773A (en) | 1991-08-27 |
| DK91591D0 (en) | 1991-05-15 |
| JPH04501679A (en) | 1992-03-26 |
| DK91591A (en) | 1991-05-15 |
| AU4507389A (en) | 1990-06-12 |
| SE8804141L (en) | 1990-05-17 |
| SE465604B (en) | 1991-10-07 |
| WO1990005572A1 (en) | 1990-05-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |