Review of Uranium CIX and RIP Systems - ALTA Metallurgical ...

ALTA Free PaperREVIEW OF CIX AND RIP SYSTEMS FOR URANIUMEXTRACTIONPresented byAlan TaylorALTA Metallurgical Services - Australiaalantaylor@altamet.com.au

ALTA Free PaperINTRODUCTION• Reciprocating basket RIP system for de-sanded slimesintroduced in USA in 1955.• CSIRO jigged bed RIP system piloted at Rum Jungle,Australia in 1958, but not commercialized.• Screen-mix RIP systems in USA in late nineteen fifties.Later used in Spain, USSR, and Eastern Europe. (alsoused for RIL).• Fluidized bed CIX systems introduced for unclarifiedsolutions in late nineteen sixties and seventies USA,Canada, and RSA.• Higgins loop moving bed applied nineteen seventies for Ufrom copper dump leach solution and then ISL solutions.• RIP and RIL systems have been used in Russia and theformer USSR.ALTA 2008 2

ALTA Free PaperCURRENT STATUS• Porter type multiple tank fluidized bed system iscurrently operating at Rossing acid leach , Namibia(Eluex arrangement; ie IX followed by SX).• New NIMCIX fluidized bed system installed atAngloGold’s Vaal River plant in RSA (also eluex).• Kemix RIP system included in Paladin’s KayelekeraProject under construction in Malawi.• RIP included in included in various feasibility studiesincluding Toro Energy’s Lakeway-Centipede Projectin Western Australia.ALTA 2008 3

ALTA Free PaperADVANTAGES• CIX can operate on unclarified solutions and RIP or RIL onslimes or finely ground ore (SX and fixed bed IX needclarified solutions).• Reduces cost of, or, eliminates solid/liquid separationcapex and opex.• In some cases reduces soluble uranium loss.• Applicable to difficult to settle ores due to clays and slimes.• Applicable to both acid and alkaline solutions (SX onlysuitable for acid systems).• Resins not soluble, which eliminates environmentalcontamination and attack on some construction materialsdue to organics which can occur with SX.• Smaller footprint area, depending on type of system.• Reduces fire risk inherent with SX.ALTA 2008 4

ALTA Free PaperDISADVANTAGES• Slower kinetics than SX.• Lower selectivity, therefore less pure product when usingstrong base resins. Commonly coupled with small SXcircuit to improve product purity- eluex process.• Weak base resins can get close to SX product purity buthave slower kinetics and lower SG• Resins degrade with mechanical attrition & osmotic shock.• Sensitive to silica, which tends to precipitate in the pores.• Suffers from poisons, eg Mb, silica, S, polythionates, Ti, Zr,Th, organics, CaCO 3 (alkaline solutions) which reducereactivity and loading. Periodic regeneration can be used.• Possible regenerants include caustic, ammonium hydroxideor nitrate, ammonium bifluoride, sodium chloride, sodiumsulphide or sulphite, sulphuric, hydrochloric or nitric acid.ALTA 2008 5

ALTA Free PaperACID LEACH-SXFLOWSHEETALTA 2008 6

ALTA Free PaperACID LEACH-CIXCIX-SXFLOWSHEET(ELUEX)ALTA 2008 7

ALTA Free PaperACID LEACH-RIPRIP-SXFLOWSHEET(ELUEX)ALTA 2008 8

ALTA Free PaperACID RIL-SXFLOWSHEET(ELUEX)ALTA 2008 9

ALTA Free PaperALKALINELEACH-RIPFLOWSHEETALTA 2008 10

ALTA Free PaperCIX SYSTEMSALTA 2008 11

ALTA Free PaperCURRENTLY USED URANIUM CIX SYSTEMS• NIMCIX fluidized bed column system in operation atVaal River South, South Africa – eluex arrangement.• Porter multiple tank countercurrent fluidized bedsystem in operation at Rossing, Namibia – eluexarrangement.ALTA 2008 12

ALTA Free PaperNIMCIX SYSTEM• Developed in late nineteen sixties by NIM (nowMintek) in RSA; based on Cloete-Streat conceptpreviously developed at Imperial College, UK.• Several plants built in RSA in nineteen seventies forunclarified acid leach solutions.• One plant installed at Grants New Mexico 1980 forcarbonate recycle tails pond solution.• Uses orifice plates. A cap is placed over each hole inbottom tray to reduce resin transfer from bottom trayand avoid depletion of resin.• Transfer of resins is under hydraulic pressure viatransfer bins, and is automatic.ALTA 2008 13

ALTA Free PaperTYPICALNIMNIMCIXSYSTEMALTA 2008 14

ALTA Free PaperNIMCIXINSTALLATION(Ref: MiningMagazine,June 1996)ALTA 2008 15

ALTA Free PaperNIMCIX COLUMN INSTALLATION AT VAAL RIVERSOUTH, SOUTH AFRICA(Ref: Mining Mirror Oct. 2007)ALTA 2008 16

ALTA Free PaperPORTER SYSTEM• Developed by consultant R.R. Porter in USA in thenineteen seventies.• Applied to unclarified acid solution at Rossing 1976• Multiple tank countercurrent fluidized bed adsorptionsystem; typically 5 stages.• Reported to be suitable for slimes with severalpercent solids.• Solution flows continuously through the system bygravity or using interstage pumps as at Rossing.• Flows in to the bottom of each stage via a distributorand up through the vessel to form a fluidized resinbed.ALTA 2008 17

ALTA Free PaperPORTER SYSTEM (CONT.)• Loaded resin is periodically moved by airlifts (4 perunit at Rossing) from the first stage to a holding tank,and resin is sequentially transferred batchwise fromtank to tank countercurrent to the solution.• Eluted resin is then transferred to final tank, andloaded resin to the elution column (Rossing initiallyhad 3 columns in series).• Elution columns are typically downflow fixed bed.• Likely to have higher resin loss than fluidized bedcolumn designs due to number and nature of resinmovements.• Has higher footprint than columns, but lower profile –therefore more suitable for indoor location.ALTA 2008 18

ALTA Free PaperTYPICAL PORTER SYSTEMALTA 2008 19

ALTA Free PaperPREVIOUSLY USED CIX SYSTEMSFluidized bed systems:• USBM fluidized bed column.• Utah USBM fluidized bed column.• Himsley USBM fluidized bed column.Moving bed systems:• Higgins loop.ALTA 2008 20

ALTA Free PaperFLUIDIZED BED SYSTEMS• Plants of various designs operated in RSA, USA andCanada in nineteen seventies.• Suitable for slimes with a maximum particle size of 45-75micr.• Pulp density limited to 10% solids, depending on the pulpviscosity. Work has been carried out on heavy resins toextend this range.• Adsorption column typically has compartments divided byorifice plates to prevent free mixing of resin and solution incolumn as a whole and achieve stage operation. Orificesare designed so upward flow of feed stream causes resinabove each plate to expand.• Countercurrent flow obtained by incorporating periodicbrief stoppages of feed flow, and removing a portion ofloaded resin from bottom, while resin moves down fromplate to plate and eluted resin is added to top.ALTA 2008 21

ALTA Free PaperFLUIDIZED BED SYSTEMS CONT.)• Elution columns are designed to operate in a similarmanner.• For some applications a fixed bed column can be used.• Typical specific flow rate range 5-20 USGPM/Ft 2 .• Resin inventory typically 2.5 times less than fixed bed IXcolumns.• Typical resin loss up to 5% per annum.• All commercial applications to date have used strongbase resins. However, NIM (now Mintek) and DavyPowergas (now Aker Solutions) ran pilot plants withweak base resins, which indicated that product puritiessimilar to SX plants could be obtained.• Weak base resins would only be applicable for low silicasolutions. Strong base resins are less affected but silicacan still be a problem.ALTA 2008 22

ALTA Free PaperTYPICALFLUIDIZEDBED CIXCOLUMNALTA 2008 23

ALTA Free PaperUSBM FLUIDIZED BED SYSTEM• Developed by USBM, USA, the late nineteen sixties.• Applied commercially for several ISL plants in USA.• Orifice plate column, similar to NIMCIX.• Deflector plates mounted about 19 mm above eachorifice to prevent direct impingement of upflow on theresin bed and reduce the amount of resin falling backthrough the holes during the flow stoppagesALTA 2008 24

ALTA Free PaperUTAH FLUIDIZED BED SYSTEM• Several commercial plants were built in New Mexicoto recover uranium from mine waters and from ISLsolutions.• Comprised modules of two units in series; each unitwas a single stage fluidized bed.• Feed solution flowed down a central feed pipe thenup through an orifice plate through a bed of fluidizedresin, then overflowed to the next unit.• Periodically one of the units taken off line and resintransferred to conventional fixed bed elution column.• Adsorption from dilute carbonate solution involves alarge driving force, so that a relatively high efficiencyis obtained in few stages.ALTA 2008 25

ALTA Free PaperTYPICALUTAH DESIGNALTA 2008 26

ALTA Free PaperHIMSLEY FLUIDIZED BED SYSTEM• Developed by Himsley Engineering in Canada.• Commercial plants were built in the nineteenseventies in Canada, RSA and USA for unclarifiedacid leach solution and for uranium from copperleach solution.• Orifices not used. Each plate has central singleinverted weir flow distributor.• Transfer of resin from adsorption to elution ishydraulic via a measuring chamber used to setamount of resin to be transferred, remainder beingreturning to bottom of adsorption column. A washingstep can be incorporated.ALTA 2008 27

ALTA Free PaperHIMSLEY FLUIDIZED BED SYSTEM (CONT.)• Movement of resin down the column is sequential,starting from the second bottom to the bottom plate,and is achieved by pumping solution at a higher ratethan the feed flow. Thus there are no stoppages, andcolumn operation is continuous.• Nature of the resin transfer between stageseliminates preferential downflow of coarser resinbeads, which can occur in orifice plate columnsdesigns.• Elution takes place in a downflow multi-stage packedmoving bed.• Resin is pushed up the column, and overflows backto the adsorption column. A water rinse is included,and a scrubbing step can also be used if appropriate.ALTA 2008 28

ALTA Free PaperTYPICAL HIMSLEY SYSTEMALTA 2008 29

ALTA Free PaperMOVING BED SYSTEMS: HIGGINS LOOP• Developed in nineteen sixties at Oak Ridge National Lab.• Currently available through Severn Trent Services, USA.• Suitable for very dilute solutions with low solids content.• Commercial operation installed at Kennecott BinghamCanyon operation in nineteen seventies for recovery ofuranium from copper dump leach solution. Eluate wastreated by SX. Also was used for alkaline ISL.• Continuous countercurrent pulsed bed system consistingof single closed loop - by valves.• Resin is moved in small increments by water pressurepulse action during which solution flows are stopped.• Solutions flow countercurrently to the resin in all sections.ALTA 2008 30

ALTA Free PaperHIGGINS LOOP (CONT.)• Advantages include :− Compact design, with low footprint.− Ability to operate at high solution flow rates.− Simple control.• Disadvantages include:− Valves close on resins, which will increase resin loss.− Resin movements in adsorption and elution cannot beseparated, which reduces flexibility.− Limited to feed solution with low solids content.(Himsley Engineering of Canada also developed amoving bed contactor which was applied commercially.)ALTA 2008 31

ALTA Free PaperHIGGINSLOOPSYSTEMALTA 2008 32

ALTA Free PaperHIGGINS LOOPINSTALLATION(POTASIUMCARBONATEPRODUCTION)(Ref: Severn Trentweb site)ALTA 2008 33

ALTA Free PaperOTHER AVAILABLE CIX SYSTEMS• Clean Teq cFLX continuous fluidized liquid extractionsystem.• Clean Teq cLX continuous liquid extraction system.• Gekko G-REX Resin Ion Exchange Column.• SepTor carousel system.• IONEX carousel system.• ISEPS carousel system.ALTA 2008 34

ALTA Free PaperCLEAN TEQ CFLX SYSTEM• Available from Clean Teq, Australia.• Series of fluidized columns with countercurrent flows.• Loaded resin airlifted from first contactor to elution.• Interstage tanks and pumps eliminates cascade system.• Utilizes expansion of resin bed to allow good contact andmixing with solutions, while allowing particulates to pass.Bed expansion up to 200% to avoid channelling andblockages.• Solid concentrations up to 10% can be processed.• Resin transportation from bottom of columns using airliftssimilar to Porter system.• No screens needed, columns designed for expansion ofsmallest resin particles and a resin disengagement.ALTA 2008 35

ALTA Free PaperCLEAN TEQ CFLX ARRANGEMENT(Ref: Clean Teq paper at ALTA 2008)ALTA 2008 36

ALTA Free PaperCLEAN TEQ CLX SYSTEM• Continuous countercurrent ion exchange system.• Packed bed column with liquid upflow resindownflow.• Loaded resin transferred via airlift to a fluidized waterwash column to remove particulates.• Allows for up to 100ppm solids in feed solutionwithout affecting performance.ALTA 2008 37

ALTA Free PaperCLEAN TEQ ELUTION SYSTEM• Utilizes countercurrent operation to ensure highconcentration and purity pregnant liquors withminimum resin inventory.• Can be designed to fit with all the different types ofClean-iX® Systems.• Generally preceded by a fluidized wash column toremove particulates from resin to protect the purity ofthe pregnant liquor stream.• Resin is airlifted from bottom of wash column to theelution column.ALTA 2008 38

ALTA Free PaperCLEAN TEQELUTIONARRANGEMENT(Ref: Clean Teqpaper at ALTA2006)ALTA 2008 39

ALTA Free PaperGEKKO G-REX SYSTEM• Available from Gekko Systems, Australia.• Multistage countercurrent, pulsed, resin ion exchangecolumn contactor. Stages separated by internal screens.• Can handle unclarified solutions with up to 3% solids.• Feed flows down column, column pulsed to fluidise resin.• Resin transferred upwards between compartments usingeductor.• Loaded resin transferred to upflow batch elution column.• Developed for gold recovery, but applicable to other IXprocesses.• Has small footprint designed for low resin wear.ALTA 2008 40

ALTA Free PaperMark II – G-REX SYSTEM FOR GOLD, ARGENTINA(Ref: Gekko paper at ALTA 2008)ALTA 2008 41

ALTA Free PaperSEPTOR CAROUSEL SYSTEM• Available from SepTor Technologies (Outotec),Netherlands.• Carousel arrangement with turntable and drive system.• Multiport Distributor Valve with PTFE inner seal.• Stationary bottom part with inlet/outlet fluid connectionports.• Stepwise rotating top part with corresponding inlet/outletpiping to/from columns.• Reduced resin requirement (40-60%) versus fixed bedsystems.• Flexibility to modify process while operating.• Suitable for solutions with low suspended solids.ALTA 2008 42

ALTA Free PaperSEPTOR ARRANGEMENT (Ref: Outotec Presentation ALTA 2006)ALTA 2008 43

ALTA Free PaperSEPTOR INSTALLATION (Ref: Outotec Presentation ALTA 2006)ALTA 2008 44

ALTA Free PaperSEPTOR CENTAL VALVE (Ref: Outotec Presentation ALTA 2006)ALTA 2008 45

ALTA Free PaperIONEX CAROUSEL SYSTEM• Available form Ionex Separations Inc., USA.• Similar concept and alternative to SepTor.ALTA 2008 46

ALTA Free PaperISEPS CAROUSEL SYSTEM• Available form Calgon Carbon Corporation, USA.• Similar concept and alternative to SepTor.ALTA 2008 47

ALTA Free PaperRIP SYSTEMSALTA 2008 48

ALTA Free PaperCURRENTLY USED RIP SYSTEMSKEMIX PUMP CELL• Included in Keyelekera Plant, Paladin Energy, Malawi,commissioning due March 2009.• Available from Kemix Pty Ltd, South Africa.• Commercial installations for gold CIP-CIL-RIL.• Resin-pulp separation by cylindrical wiped screenequipped with pump for interstage transfer of pulp.• Resin is not moved between stages, reducing breakdown.• Series of pump cells set at the same elevation operating ina carousel mode by rotating the feed and discharge pointsto simulate countercurrent flow of resin.• Relatively small retention time per stage.ALTA 2008 49

ALTA Free PaperKEMIX PUMP CELL INSTALLATION FOR GOLD(Ref: Kemix Web Site)ALTA 2008 50

ALTA Free PaperPREVIOUSLY USED RIP SYSTEMS• Reciprocating basket system• Screen-mix systemALTA 2008 51

ALTA Free PaperRECIPROCATING BASKET SYSTEM• Applied to both acid and carbonate leach pulps.• Limited to de-sanded slimes, maximum particle size 45micr. Pulp density limited to < 10% solids.• Resin make-up due to attrition was 15-20% per annum.• Suffered from relatively high maintenance costs.• Baskets typically cube shaped, with stainless steel orrubber lined frames and stainless steel or plastic screencloth.• Baskets moved up and down at 6-12 strokes/minute inrectangular tanks through which feed slurry or eluantflowed.• Resin bed contracted during up stroke and expandedduring down stroke.ALTA 2008 52

ALTA Free PaperTYPICAL 14 STAGE BASKET RIP SYSTEM, USA• Typically two parallel systems of 14 stages (or banks) were used.• Each stage contained 2-10 baskets.• 6-11 stages used for adsorption at any one time.• Central distributor box could feed any bank.• interstage slurry transfer was by gravity or airlift.ALTA 2008 53

ALTA Free PaperSCREEN-MIX SYSTEM• Applied to acid leach pulps in USA, Russia and USSR.• Feed pulp de-sanded to a maximum particle size of 45-75micr.• Pulp density limited to 12-20% solids in USA, though oneoperation achieved 30%.< 10% solids. Operation with upto 50% solids reported in USSR.• Resin make-up due to attrition was 20-30% per annum.However, resin inventory was only one third to one half ofthat for basket systems.• Multi-stage countercurrent system with interstage transferof pulp and resin via airlifts and vibrating screens.Stationary sloping screens have been used in USSR andEastern Europe together with separate airlifts for resintransfer.• Screen maintenance cost significant.ALTA 2008 54

ALTA Free PaperSCREEN-MIX SYSTEM (CONT.)• Typically 6-7 adsorption stages, 10-12 elution, 1-2 wash.Fixed bed elution also used.• Typical resin size range 300 to 850 micr. as used in IXcolumns. Finer than used for baskets, cheaper, tougherand more efficient.• Typically, interstage screen size opening was 210 micr.• Forerunner of gold CIP designs. Subsequent extensiveexperience gained in gold CIP and RIP plants can now beutilized for uranium RIP.ALTA 2008 55

ALTA Free PaperTYPICAL AIR AGITATED SCREEN-MIX SYSTEM, USAALTA 2008 56

ALTA Free PaperOTHER AVAILABLE RIP SYSTEMS• Clean Teq Clean-iX® system• MeTRIX systemALTA 2008 57

ALTA Free PaperCLEAN TEQ CLEAN-IX SYSTEM• Uses low shear, two-stage mechanical agitator to mixthe resin and pulp.• Uses airlift to lift both resin and pulp to woven wirestatic separation screen.• Air agitated alternative also available.• Air agitated system has higher poser consumptionbut lower resin attrition loss.• Clean Teq Clean-iX® used for elution.ALTA 2008 58

ALTA Free PaperCLEAN-IXARRANGEMENTWITHMECHANICALAGITATION(Ref: Clean Teqpaper at ALTA2008)ALTA 2008 59

ALTA Free PaperMETRIX SYSTEM• Developed by Mintek and Bateman in South Africa.• Screen-mix type system in absorption and elution.• Countercurrent movement of pulp and resin.ALTA 2008 60

ALTA Free PaperMETRIX ABSORPTION CIRCUIT(Ref: Bateman-Mintek Presentation ALTA 2007)ScreenslurryslurryResin + slurryFeedResin + slurryALTA 2008 61

ALTA Free PaperMETRIX PILOT PLANT(Ref: Bateman-Mintek Presentation ALTA 2007)ALTA 2008 62