SE186686C1

SE186686C1 -

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Publication number: SE186686C1
Authority: SE
Publication date: 1963-01-01

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Uppfinnare: 0 Lindstrom Extraktion med organiska losningsmedel liar pa senare tid att stor industriell betydelse. Dylika processer anvandas saledes Mom petroleumindustrin saint mom karnenergiindustrin hi. a. vid bearbetning av bestralat bransle for utvinning av plutonium, uran eller torium. Extraktionsprocessen liar vunnit stor framgang vid behandling av atombranslen framfor alit pa grund av den goda separationen fran klyvningsprodukterna, som Or mollig under gynnsamma betingelser. En hel del olika apparatkonstruktioner ha foreslagits for vatske-vatskeextraktion. mom karnenergitekniken anvandes framfor allt sa kallade pulskolonner. Pulskolonner aro forsedda med silbottnar eller bottnar av strackmetall. I vissa fall anvandes Oven fyllkroppar. Kolonninnehallet bibringas en pulserande rorelse som overlagras den i motstrom skeende nettotransporten av de hada vatskefaserna. Den pulserande rorelsen. astadkommes vanligen med hjalp av en membran- eller kolvpump ansluten via en grenledning. Den turbulenta omrarningen och den standiga nybildningen av vatskedropparna vid passagen genom bottnarna under pulseringen get en snabb installning av fordelningsjamvikterna, varfor pulskolonnerna kunna goras kortare On konventionella fyllkroppskolonner. Inventors: 0 Lindstrom Extraction with organic solvents has recently become of great industrial importance. Such processes are thus used in the Mom petroleum industry saint mom nuclear energy industry hi. a. in the processing of irradiated fuel for the extraction of plutonium, uranium or thorium. The extraction process has gained great success in the treatment of nuclear fuels over all due to the good separation from the fission products, which is possible under favorable conditions. A lot of different apparatus constructions have been proposed for water-water extraction. mom nuclear energy technology was used above all so-called pulse columns. Pulse columns are provided with screen bottoms or stretched metal bottoms. In some cases, Oven filler bodies were used. The column contents are imparted with a pulsating motion which is superimposed on the countercurrent net transport of the hot water phases. The pulsating movement. is usually provided by means of a diaphragm or piston pump connected via a branch line. The turbulent agitation and the constant new formation of the liquid droplets during the passage through the bottoms during the pulsation gives a quick installation of the distribution equilibria, so that the pulse columns can be made shorter than conventional filler body columns.

Vid den praktiska driften av extraktionsapparater, t. ex. pulskolonner, upptrader ofta, sarskilt vid extraktion av radioaktiva losningar, svarigheter vid separationen av de hada faserna. Dessa kolonner aro i allmanhet forsedda med avslutande vidare sektioner for dosering och separering. I allmanhet arbetar man med en kontinuerlig vattenfas och en lattare dispergerad organisk fas och separation sker din i kolonnens ovre ande. Reglering av driften sker pa sin satt att tillfOrseln av den tyngre komponenten i kolonnens livre ande eller avloppet av densamma vid den nedre On-den avpassas sin att laget av gransytan mellan de tva faserna i kolonntoppen Mlles vid konstant niva. Eftersom avloppet av den lattare fasen i allmanhet sker via braddavlopp erfordras jute flagon spedell reglering for denna. For indikerin.g av gransytans lage och reglering av tilFfOrsel och avlopp sin att gransytan halles vid den konstanta nivan anvandes foretradesvis pneumatiska metoder men Oven elektrisk nivaindikering kommer till anvandning. Den utrustning som erfordras for denna kontroll och reglering Or komplicerad, vilket Or en nackdel sarskilt vid arbetet med starkt radioaktiva lOsningar pa grund av svarigheterna med underhall ()eh reparation. En allvarlig olagenhet Or ocksa forekomsten av uppslammade fororeningar, som anlagras i gransytan. Nar gransytan ligger kolonntoppen och man arbetar med en tyngre kontinuerlig fas, t. ex. en vattenfas och en lattare dispergerad fas, t. ex. en organisk vatskefas kommer den lattare vatskefasen, som vid ett extraktionssteg innehaller den renade produkten, att passera genom det ofta starkt fororenade gransskiktet, varvid olOsta eller uppslammade radioaktiva foreningar ryckas med i den lattare fasen. I praktiken sanker detta dekontamineringsfaktorerna till den grad att produktspecifikationerna ej kunna uppfyllas. Det hander ofta att sadana storningar medfor drifts avbrott langre tid for rengoring och upprensning av kolonnen. En mojlighet att reducera inverkan av de namnda stOrningarna Or att lagga gransskiktet i kolonnens nedre ande, varvid man arbetar med en kontinuerligt lattare fas, t. ex. en organisk vatskefas och en. dispergerad tyngre f as, t. ex. en vattenfas. Risken for kontamination av produktlosningen pa grund av medryckta radioaktiva fororeningar fran grans- 2— — skiktet fir da mindre. Indikeringen av gransskiktets lage blir dock smarare och den pneumatiska tekniken ãr givetvis ej praktiskt anvandbar i detta fall. Aven vid detta driftssatt kommer fororeningar att ackumuleras i kolonnen och man maste dart& periodiskt avstanga denna for upprensning. In the practical operation of extraction apparatus, e.g. pulse columns, often occur, especially in the extraction of radioactive solutions, similarities in the separation of the had phases. These columns are generally provided with terminating further sections for dosing and separation. In general, you work with a continuous aqueous phase and a lighter dispersed organic phase and separation takes place in the upper spirit of the column. Regulation of the operation takes place in such a way that the supply of the heavier component in the free spirit of the column or the drain thereof at the lower end is adapted so that the layer of the spruce surface between the two phases in the top of the column is measured at a constant level. Since the drain of the lighter phase generally takes place via brad drain, jute flagon leprosy regulation is required for this. For indicating the condition of the spruce surface and regulating the supply and drainage that the spruce surface is kept at the constant level, pneumatic methods are preferably used, but electrical level indication is also used. The equipment required for this control and regulation is complicated, which is a disadvantage especially when working with highly radioactive solutions due to the responsibilities of maintenance () eh repair. A serious maladaptation Or also the presence of slurry contaminants, which are deposited in the spruce surface. When the spruce surface is at the top of the column and you work with a heavier continuous phase, e.g. an aqueous phase and a later dispersed phase, e.g. In an organic liquid phase, the lighter liquid phase, which in an extraction step contains the purified product, will pass through the often heavily contaminated spruce layer, whereby unresolved or suspended radioactive compounds are entrained in the lighter phase. In practice, this reduces the decontamination factors to the extent that the product specifications cannot be met. It often happens that such disturbances lead to interruptions in operation for a longer period of time for cleaning and purification of the column. A possibility to reduce the influence of the mentioned disturbances Or to lay the spruce layer in the lower end of the column, whereby one works with a continuously lighter phase, e.g. an organic liquid phase and a. dispersed heavier f as, e.g. an aqueous phase. The risk of contamination of the product solution due to entrained radioactive contaminants from the granule layer then decreases. However, the indication of the layer of the spruce layer becomes smarter and the pneumatic technique is of course not practically usable in this case. Even with this commissioning, contaminants will accumulate in the column and you must dart & periodically shut it down for purification.

En annan kand princip fir att avleda ett i kolonnen nivareglerat grfinsskikt Iran kolonnen och avlagsna fororeningarna i en yttre krets. Another is a principle for diverting a level-regulated graphene layer in the column to the Iran column and removing the contaminants in an external circuit.

Enligt foreliggande uppfinning undvikes anvandning av I kolonnen placerade nivaindikerande organ, t. ex. pneumatiska eller elektriska system, frin milka impulser reglerar tillforsel eller avlopp av den tyngre fasen och erhalles en utomordentligt enkel reglering av kolonnens drift. Enligt uppfinningen avledes en i gransskiktet mellan faserna befintlig vatskeblandnin.g frail kolonnen och befrias fran olosta eller uppslammade partiklar t. ex. genom filtrering, varefter vatskeblandningen ledes till en anordning, som ombes5rjer en uppdelning av vatskeblandningen i laser om detta ej skett i saraband med avlagsnandet av uppslamraade fororeningar och samtidigt tjanstgor som nivhregulator f8r gransskiktet I extraktionsapparaten. De darvid erhallna separerade matskefaserna kunna sedan eventuellt aterforas till extraktionsapparaten. Denna i en till kolonnen ph den niva, dar gransskiktet avses ligga, ansluten grenledning inghende nivareglerande anordningen fungerar ph sâ satt att den mid 8verskott av tung fas i vatskeblandningen okar avloppet av denna fas Iran anordningen och mid underskott av tung fas nainskar samma avlopp. En hojning av gransskiktets nivâ i kolonnen medf8r okad halt av tung fas i vatskeblandningen och darmed elt okat avlopp av tung fas frail den nivareglerande anordningen grenledningen, nagot som motverkar gransskiktets nivahojning. Ph motsvarande salt motverkas en sankning av gransskiktets niva av ett minskat avlopp av tung fas fran anordningen. F8r att astadkomma denna verkan hos en nivareglerande anordning kan denna besta av en behallare som är forsedd med ett oppet stigror for den lattare fasen och ett andra oppet stigror for den tyngre fasen, milka bada stigror Oro forsedda med avlopp placerade pa avpassad niva.. Nivan f Or dessa avlopp kan antingen bestammas matematiskt ur de hydrostatiska och hydrodynamiska tryek, som 'Ada i stigror och kolonn och ur de till kolonnen forda och frau kolonnen avRada mfingderna av vatskefaserna i de aktuella fallen, men de kunna cash bestammas rent experimentellt. Lampligast fir att Ora stigrOrens avlopp forskjutbara, sh att, i samband riled att stromningarna av de bada vatskefaserna genom kolonnen avpassas till onskade forhallanden genom avpassning av tillforsel och avlopp for resp. faser, nivaerna ph stigrOrets avlopp installas sá att gransskiktet mellan faserna i kolonnen ligger niva med grenledningen. I stallet for att utrusta stigroren med forskjutbara avlopp kunna dessa ha en fast niva och behallaren vara fOrsedd med en ventil som reglerar den tyngre fasens utlopp fran behallaren. Ventilen kan hi. a. besta av en flottor som tatar mot ett sate vid den tyngre fasens. utlopp i behallaren. Vid okning air mangden tyngre fas i vatskeblandningen lyftes flottoren, vilket medfor ett okat avlopp air denna fas och vid minskning av mangden tyngre fas i vatskeblandningen sjunker flottoren, vilket minskar avloppet av denna fas. F8r att undvika stao'bnerande latt vatskefas kan en transport ir adenna genom grenledningen ombesorjas av en pump eller annan cirkulationsanordning. According to the present invention, the use of level indicating means placed in the column is avoided, e.g. pneumatic or electrical systems, free milk impulses regulate the supply or drain of the heavier phase and obtain an extremely simple regulation of the operation of the column. According to the invention, a liquid mixture present in the boundary layer between the phases is diverted from the column and freed from undissolved or suspended particles, e.g. by filtration, after which the liquid mixture is passed to a device which provides for a division of the liquid mixture into laser if this has not been done in conjunction with the removal of suspended contaminants and at the same time serves as a level regulator for the spruce layer in the extraction apparatus. The resulting separated phase phases can then possibly be returned to the extraction apparatus. This level-regulating device connected to the column ph the level where the boundary layer is intended to lie, branch branch, works in such a way that the mid-excess of heavy phase in the liquid mixture increases the drain of this phase Iran device and mid-deficit of heavy phase nears the same drain. An increase in the level of the spruce layer in the column results in an increased content of heavy phase in the liquid mixture and thus an increased drain of heavy phase from the level-regulating device branch line, which counteracts the level increase in the spruce layer. Ph corresponding to a salt, a lowering of the level of the spruce layer is counteracted by a reduced heavy phase drain from the device. In order to achieve this effect in a level regulating device, it may consist of a container provided with an open riser for the lighter phase and a second open riser for the heavier phase, with both risers being provided with drains placed at the appropriate level. These sewers can either be determined mathematically from the hydrostatic and hydrodynamic pressures, such as' Ada in risers and column and from the to the column forda and frau column avRada mfingderna of the water phases in the cases in question, but they can cash be determined purely experimentally. Lampligast fir att Ora stigrOren's drains displaceable, sh att, in connection riled that the flows of the bath liquid phases through the column are adapted to desired conditions by adjusting the supply and drain for resp. phases, the levels ph stigROrets drain is installed so that the spruce layer between the phases in the column is level with the branch line. Instead of equipping the risers with displaceable drains, these can have a fixed level and the container be provided with a valve which regulates the outlet of the heavier phase from the container. The valve can hi. a. consists of a fleet that taters against a sate at the heavier phase. outlet in the container. When the amount of heavier phase in the liquid mixture is increased, the float is lifted, which leads to an increased drain in this phase, and when the amount of heavier phase in the liquid mixture is reduced, the float sinks, which reduces the effluent of this phase. To avoid stagnant light phase, a transport through the branch line can be provided by a pump or other circulation device.

Det praktiska genomforandet av forfaringssattet skall beskrivas narmare i det 101j ande. En. utforingsform Or schematiskt askadliggjord i fig. 1. I detta fall Or den lattare fasen homogen och gransskiktet ligger foljaktligen i kolonnens 1 nedre ande 2. Pulskolonnen Or konstruerad ph kant sat, Den organiska fasen inledes vid anslutningen 3 medan den tunga fasen inledes mid 4. Avloppet for den lata fasen sker vid 5 medan den. tunga fasen avga'r huvudsakligen mid 6. Kolonndelen 7 innehaller perforerade bottnar 8. Pulseringen sker med hjalp av pulseringsanordningen 9 som Or ansluten till den nedre anden av kolonnen. via ledningen 10. Utmatningen av den tunga fasen kan ske t. ex. med hj alp ay pulseringen i vatskan: en backventil 11 forhindrar aterflode, reglering ay flodet sker med hjalp av strypventilen 12 och vatskeavloppet sker vid 13. Man kan givetvis Oven an.vanda en pump for detta andamal eller nhgon ammn lamplig anordning for reglering av avloppsflodet. Reningskretsen Or ansluten till kolonnens nedre ande mid 14 som befinner sig i det plan dar gransytan 15 avses ligga. Reningskretsen bestar av en filterenhet 16 samt en nivareglerande anordning 17, mars uppgift ocksa. Or att fordela de bhda vatskefaserna som ledas genom filterenheten sasom. skall visas narmare nedan. Anordningen 17 bestar av ett cylindriskt karl 18 med ett stigror 19 for den 'Ware fasen samt ett stigror 20 for den tyngre fasen. Stigroren aro forsedda med i h5jdled forskjutbara avlopp 21 och 22. Avloppen installas pa shdan niva att faserna na avrinningsniva da. gransskiktet 15 i kolonnen ligger i niva med grenledningens 23 anslutning 14. Kolonnen Or ph den niva dOr grenledningen. Or ansluten utrustad med en styrskarm 24, vilken leder gransskiktsfororeningarna mot grenledningen. The practical implementation of the procedure will be described in more detail in the 101st. One. embodiment Or schematically ash-damaged in Fig. 1. In this case Or the lighter phase is homogeneous and the spruce layer is consequently located in the lower end of column 1. The pulse column Or constructed ph edge sat, The drain for the lazy phase occurs at 5 while it. the heavy phase emits mainly mid 6. The column part 7 contains perforated bottoms 8. The pulsation takes place with the aid of the pulsation device 9 which Or is connected to the lower spirit of the column. via line 10. The output of the heavy phase can take place e.g. with the help of the pulsation in the water: a non-return valve 11 prevents backflow, regulation of the flood takes place with the help of the throttle valve 12 and the water drain takes place at 13. You can of course also use a pump for this purpose or any other suitable device for regulating the sewage. . The cleaning circuit Or is connected to the lower end 14 of the column which is located in the plane where the spruce surface 15 is intended to lie. The purification circuit consists of a filter unit 16 and a level regulating device 17, March information also. Or to distribute the bhda liquid phases conducted through the filter unit as well. will be shown in more detail below. The device 17 consists of a cylindrical vessel 18 with a riser 19 for the true phase and a riser 20 for the heavier phase. The risers are provided with vertically displaceable drains 21 and 22. The drains are installed at such a level that the phases reach the run-off level then. the spruce layer 15 in the column is level with the connection 14 of the branch line 23. The column Or ph the level dOr the branch line. Or connected equipped with a guide arm 24, which leads the spruce layer contaminants towards the branch line.

I fig. 2 -visas en annan utf5ringsform av den nivareglerande anordningen 25. Den bestar av en behallare 26 med ett stigror 27 for den lattare fasen och ett stigror 28 for den tyngre — — fasen, vilka aro fOrsedda med avloppen 29 och 30. Behallaren innehaller vidare en hot-for 31 som tatar mot sal at 32. Denna Hottar har sadan vikt och deplacement att dess lage är beroende av fasgransens lage 33 i den nivareglerande anordningen 25. Vid overskott av tung fas i detta karl kommer flott5ren att lyftas, varvid den tyngre fasen kan avrinna genom stigroret 28. Vid underskott av tung I as slutes pa motsvarande satt ventilen. Vissa fardelar vinnas med flottorventilen, vilka maste vagas mot den mojlighet till driftstorning som denna extra komponent i systemet innebar. Flottorventilen utgor en extra sakerhetsfaktor for att latt fas ej letar sig ut till utloppet for den tunga fasen 30, vilket kunde tankas intraffa vid felmanover vid start av kolonnen etc. Vidare blir nivaregleringen oberoende av det hydrostatiska trycket i reningskretsen. Fig. 2 shows another embodiment of the level regulating device 25. It consists of a container 26 with a riser 27 for the lighter phase and a riser 28 for the heavier phase, which are provided with the drains 29 and 30. The container further contains a hot-for 31 which tates against sal at 32. This Hottar has such weight and displacement that its bearing is dependent on the bearing of the phase boundary 33 in the level regulating device 25. In case of excess of heavy phase in this vessel the float will be lifted, whereby the heavier phase can drain through the riser 28. In the event of a deficit of heavy I as, the valve closes in a corresponding manner. Some parts of the vessel are won with the float valve, which must be weighed against the possibility of operational disturbance that this extra component in the system entailed. The float valve is an additional safety factor so that the light phase does not find its way out to the outlet for the heavy phase 30, which could be refueled during error maneuvering at the start of the column, etc. Furthermore, the level control becomes independent of the hydrostatic pressure in the purification circuit.

TvAngscirkulation av 1511 fas genom reningskretsen kan astadkommas pa sa salt att en viss ringa mangd C, avsuges ur stigaren 27 pa den nivareglerande anordningen med hjalp av pumpen 39. Detta flode C aterfores lampligen till inloppskarlet for den latta f asen. I stallet fOr pumpen 39 kan man aven anvanda braddavlopp eller backventil och strypventilsom vid 11 och 12 i fig. 1 — eftersom en viss om oak ringa pulsering kan leta sig fram aven till denna punkt i systemet. Forced circulation of 1511 phase through the purification circuit can be effected so salty that a certain small amount C is sucked out of the riser 27 on the level regulating device by means of the pump 39. This flow C is suitably returned to the inlet vessel for the light phase. Instead of the pump 39, it is also possible to use a brad drain or non-return valve and throttle valve as at 11 and 12 in Fig. 1 - since a certain, if not small, pulsation can also be found at this point in the system.

Cirkulationen av den tunga fasen genom reningskretsen regleras genom inloppsflodet T vid 4 i fig. 1 samt avloppsfKidet A vid 13. En positiv differens, T—A = D uppehalles varvid flOdet D kommer att avledas genom reningskretsen till avloppet 22 (fig. 1) eller till avloppet (fig. 2). The circulation of the heavy phase through the purification circuit is regulated by the inlet flow T at 4 in Fig. 1 and the effluent flow A at 13. A positive difference, T — A = D is maintained whereby the flow D will be diverted through the purification circuit to the drain 22 (Fig. 1) or to the drain (fig. 2).

Fig. 1 visar endast en reningskrets hell medan en andra reningskrets tankes ansluten vid 34. Fig. 1 shows only one purification circuit well while a second purification circuit is thought to be connected at 34.

Flera reningskretsar bOr namligen arrangems parallellt sa att man vid behov kan koppla bort en reningskrets for dekontaminering, varvid vatskeflodet avledes genom en alternativ reningskrets. Detta kan praktiskt tillga pa foljande salt, varvid antages att ledningen 34 ar fOrbunden med en reningskrets lika den vid anslutningen 14. Den visade reningskretsen avstanges med ventilen 35. Denna ventil kan ocksa tjanstgora som strypning fOr den handelse att motstandet i filtret 16 och reningskretsen i ovrigt Or sO. ringa att en avsevard pulsering sker I reningskretsen. Vatten infores genom ledningen 36 och far fOrtranga vatskorna i reningskretsen, vilka ga. for avfallsbehandling. Darefter infores genom 22 och avledes genom anslutningen 36 lampliga losande vatskor t. ex. syrablandningar som sakta fa stromma genom reningskretsen tills dess filtret rensats. Systemet skoljes med vatten samma vag och slutligen med vatten i stromningsriktningen 36 till 22. Reningskretsen Or nu fylld med vatten och kart Ater inkopplas. Anvandandet av tva anslutningsror 37 ()eh 38 mellan filterkarlet och den nivareglerande anordningen beror framst pa att man viii midvika gaskuddar i filterkarlet. Gaskuddar kunna givetvis ocksa_ elimineras genom en luftningsledning pa filterkarlets hogsta niva. Utforandet av filtret bestammes av de aktuella drifflosningarna och fororeningarna. I allmanhet Or det ej fraga om egentlig filtrering utan avsikten Or att de uppslammade fiiroreningarna skola uppfangas och fastna i filterkroppen. Denna bor darfiir ha en stor yta men samtidigt ett obetydligt stromningsmotstand och stora kanaler. Packningar bestaende a-v hoprullad me-. tallvav eller metallull liksom glasfibervav Oro mycket lampliga for detta andamal. Man kan ocksa tanka sig att anyanda utbytbara filterkroppar, vilka avlagsnas ur filterkarlet med hjalp av manipulatorer och som sedan kastas efter anyandningen. I de ovansthende exemplen utnyttjas ett filter bestaende av en vavd matta av syrafast staltrad som packats till en filterkropp. Namely, several purification circuits should be arranged in parallel so that, if necessary, a purification circuit for decontamination can be disconnected, whereby the liquid flow is diverted through an alternative purification circuit. This can be practically added to the following salt, assuming that the line 34 is connected to a purge circuit similar to that of the connection 14. The purge circuit shown is shut off with the valve 35. This valve can also serve as a choke for the action of the resistor in the filter 16 and the purge circuit otherwise Or sO. call that a considerable pulsation takes place in the purification circuit. Water is introduced through line 36 and causes the water droplets in the purification circuit to evaporate. for waste treatment. Then light loosening water shoes are inserted through 22 and diverted through the connection 36, e.g. acid mixtures which slowly flow through the purification circuit until the filter is purified. The system is rinsed with water the same vague and finally with water in the flow direction 36 to 22. The purification circuit Or now filled with water and map Ater is connected. The use of two connecting pipes 37 () eh 38 between the filter vessel and the level regulating device is primarily due to the fact that gas cushions in the filter vessel are to be avoided. Gas cushions can of course also be eliminated through an aeration line at the highest level of the filter vessel. The design of the filter is determined by the actual drift solutions and contaminants. In general, it is not a question of actual filtration but of the intention Or that the suspended contaminants should be captured and trapped in the filter body. This should therefore have a large surface area but at the same time an insignificant flow resistance and large channels. Packs consisting of a-v rolled up with-. pine or metal wool as well as fiberglass cloth Oro very suitable for this purpose. It is also conceivable that any other replaceable filter bodies, which are removed from the filter vessel with the aid of manipulators and which are then thrown away after any inhalation. In the above examples, a filter consisting of a woven mat of acid-resistant steel row packed into a filter body is used.

En liknande anordning utnyttjas vid tilllampning av uppfinningen for en kolonn med den tunga rami homogen och med gransskiktet i kolonnens ovre aride. Verkningssittet Or i princip detsamma och nagon narmare beskrivning Or dad& ej nodvandig. A similar device is used in the application of the invention for a column with the heavy frame homogeneous and with the spruce layer in the upper arid of the column. The site of action Or basically the same and no closer description Or dad & not necessary.

Vatskefliidet som avledes till reningskretsen har ndgot olika karaktar -vid anslutning av reningskretsen till kolonnens ovre resp. nedre ande. Om kolonnen utfor en enkel extraktion av ett metallsalt frail en vattenlosfling med hjalp av ett organiskt, lattare lösningsmedel kommer i fig. 1 flodet till reningskretsen att innehalla dels frail metallsalt befriad vattenlosning oeh dels rent organiskt lOsningsmedel. I detta fall forekommer inga storre problem, vattenlosningen gar i avloppet och det organiska losningsmedlet ater infores till inmatningskarlet. Om gr5nsskiktet Or belaget i den ovre kolonnanden innehaller daremot bade det organiska losningsmedlet och vattenlosningen_ det vardefulla metallsallet. I detta fall atergar lampligen vattenlosningen till inmatningskarlet for denna medan det organiska losningsmedlet aterinfores till inmatningspunk.ten for detta. Man kan aterfora det organiska losningsmedlet till preduktkarlet men detta Or i vissa fall mindre lampligt eftersom losningsmedlet passerat genom filterkdrlet och kan ha blivit kontaminerat. The liquid flow which is diverted to the purification circuit has somewhat different character - when connecting the purification circuit to the upper resp. lower spirit. If the column performs a simple extraction of a metal salt frail an aqueous solution with the aid of an organic, lighter solvent, in Fig. 1 the river to the purification circuit will contain partly frail metal-free aqueous solution and partly pure organic solvent. In this case no major problems occur, the water discharge goes into the drain and the organic solvent is re-introduced into the feed vessel. If the boundary layer Or coated in the upper column end, on the other hand, contains both the organic solvent and the aqueous solution_ the valuable metal salt. In this case, the aqueous solution apparently returns to its feed vessel while the organic solvent is returned to its feed point. The organic solvent can be returned to the product vessel, but this is in some cases less suitable because the solvent has passed through the filter vessel and may have become contaminated.

Som exempel pa vatskor som kunna underkastas behandling enligt det besksivna forfaringssattet kunna namnas en salpetersur exempelvis 2-normal vattenlosning innehallande t. ex. 112 g Pu+4/1 och 300 g 1.31-6/1, utgorande den kontinuerliga fasen och fotogen innehallande I. ex. 30 viktsprocent tributylftalat som dispergerad fag. Klyvningsprodukterna stanna vid behandlingen i vat- 4— — tenlosningen medal' Pu+4 och U+6 tack vare komplexbildning med tributylftalatet loser sig i fotogenet. As examples of water shoes that can be subjected to treatment according to the described procedure, a nitric acid can be mentioned, for example 2-normal aqueous solution containing e.g. 112 g Pu + 4/1 and 300 g 1.31-6 / 1, constituting the continuous phase and kerosene containing I. ex. 30% by weight of tributyl phthalate as dispersed phage. The cleavage products stop during the treatment in the water 4— - the discharges medal 'Pu + 4 and U + 6 due to complex formation with the tributyl phthalate dissolve in the kerosene.

Aven om uppfinningen beskrivits sarskilt for del fall att extraktionsapparaten utgor en extraktionskolonn i form av en pulskolonn och behandlingslosningarna innehalla radioaktiva fOroreningar Sr det uppenbart att uppfinningen rued fordel aven kan tillampas for andra kontinuerliga extraktionsapparater och for andra behandlingslosningar. Although the invention has been specifically described in some cases the extraction apparatus is an extraction column in the form of a pulse column and the treatment solutions contain radioactive contaminants.

Claims

Pat entansprak:

1. Procedure for extraction in a continuously operating extraction apparatus, e.g. an extraction column such as a pulse column, which works with a lighter and heavier liquid phase, which forms a level-regulated spruce layer, and frail which, where the spruce layer between the liquid phases is coated, a liquid mixture is diverted and released from unresolved or suspended particles, e.g. by a filtration, characterized in that the liquid mixture after the removal of unresolved or slurry particles is led to a device, sour serves as the level regulator of the spruce layer in the extraction apparatus.

Device for carrying out the process set according to claim 1 in a continuously operating extraction apparatus (1), which at the level (15), where the boundary layer between the phases is intended to lie during operation, is provided with a level-regulating device (17, 25) and with a branch line (23) containing a device (16) for removing unloaded or suspended particles from the liquid mixture taken from the extraction apparatus (1) via the branch line (23), characterized in that the level regulating device (17, 25) is arranged according to the device for removal. of (Aosta or slurry particles in the branch line and consists of a container (18, 26) with a tipped riser (19, 27) for the lighter phase and an open riser (20, 28) for the heavier phase, which both Tigers are provided with drains (21, 29, 22, 30) placed at such a level that, when a lighter and heavier phase flows through the drains during operation, the spruce layer in the column lies in the level of the branch line (23).

Device for carrying out the process set according to claim 1 in a continuously operating extraction apparatus (1), to which at the level (15) where the boundary layer between the phases is intended to lie during operation, a branch line (23) containing a level-regulating device (25) is connected and a device (16) for removing unloaded or suspended particles from the liquid mixture taken from the extraction apparatus (1) via the branch line (23), characterized in that the level regulating device Or is arranged, after the device for removing unloaded or suspended particles in the branch line and consists of a container (26), which has an open riser (27) provided with a drain (29) for the lighter phase and a tipped riser (28) for the heavier phase provided with a drain (30), and which contains a valve comprising one against a sate (32) at the outlet of the heavier phase out of the container Ulande float (31), which valve regulates the outlet of the heavier phase through its stigro r, sa. that the spruce layer in the column is kept at the level of the branch line.

Device according to any of the patent claims, ken. 2-3, can be characterized in that a pump (39) is connected to the riser (19, 27) for the lighter phase Sr, which arranges for transport of the lighter phase through the branch line (23).

Device according to any one of patent claims 2-4, characterized in dSrav, that the device (16) Mr removal of unwrought or suspended particles consists of a replaceable filter. Request publications: UK Patents 307,868; USA 2,192,094, 2,729,549.