WO2013166528A1 - Mixer settler column - Google Patents
Mixer settler column Download PDFInfo
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- WO2013166528A1 WO2013166528A1 PCT/ZA2013/000029 ZA2013000029W WO2013166528A1 WO 2013166528 A1 WO2013166528 A1 WO 2013166528A1 ZA 2013000029 W ZA2013000029 W ZA 2013000029W WO 2013166528 A1 WO2013166528 A1 WO 2013166528A1
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- column
- fluid
- plate
- flow
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- 239000012530 fluid Substances 0.000 claims abstract description 218
- 238000012546 transfer Methods 0.000 claims abstract description 102
- 238000002156 mixing Methods 0.000 claims description 74
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- 239000007788 liquid Substances 0.000 description 85
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/04—Solvent extraction of solutions which are liquid
- B01D11/0426—Counter-current multistage extraction towers in a vertical or sloping position
- B01D11/043—Counter-current multistage extraction towers in a vertical or sloping position with stationary contacting elements, sieve plates or loose contacting elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/04—Solvent extraction of solutions which are liquid
- B01D11/0446—Juxtaposition of mixers-settlers
- B01D11/0449—Juxtaposition of mixers-settlers with stationary contacting elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
- B01F23/40—Mixing liquids with liquids; Emulsifying
- B01F23/45—Mixing liquids with liquids; Emulsifying using flow mixing
- B01F23/453—Mixing liquids with liquids; Emulsifying using flow mixing by moving the liquids in countercurrent
Definitions
- This invention relates to a mixer settler column which is capable of multistage mixing and settling.
- Mixing and settling processes for fluids are usually aimed at transferring a maximum amount of a particular material from one fluid to another.
- a material which is transferred might be dissolved in, absorbed by, or otherwise associated with, each of the two fluids.
- Multiple mixer-settler stages and counter-current flows are commonly used to achieve effective operation.
- Factors which determine the effectiveness of a counter-current multistage mixer-settler process include the following:
- the degree of mixing should be such that elements of the fluids contact each other sufficiently closely under conditions of high shear
- stage efficiency is the fractional extent towards equilibrium that mass transfer occurs in a stage
- the velocities of rising or settling particles, droplets or bubbles should be high, for low rising or settling rates limit the throughput of a process.
- a process which requires mixing and settling is usually carried out in separate mixing and settling units or in columns.
- Counter-current decantation is commonly done using multiple thickeners together with mixer units. This approach is, however, expensive and requires a large footprint. Each mixing and settling stage has limited efficiency for mass transfer and, in order to achieve efficient overall mass transfer, multiple stages, which can be expensive, and excessive dilution, are required.
- Multi-stage, counter-current mixing and settling can be done in suitably designed columns which generally have packing material or include simple plates with perforations, or complex, custom-designed plates.
- Some column-based processes are fully continuous and have steady counter-current flows, while other column-based processes make use of pulsing techniques which promote desirable flow and mass transfer characteristics.
- US3108859 describes the operation of a pulsed column in a mixer-settler mode or in an emulsion mode.
- liquid settles into distinct layers during quiescent phases of an operational cycle.
- a dispersed liquid remains dispersed in relatively small droplets, throughout the column, with no substantial change in droplet sizes occurring during the operational cycle.
- the patent describes an improvement that provides alternate physical regions in which the light liquid is dispersed within the dense liquid, and the dense liquid is dispersed within the light liquid, respectively, by means an arrangement in the column of various perforated plates, and upward- and downward-pointing nozzles on upper and lower sides of sets of sieve plates having different wetting characteristics.
- US3979281 describes a pulsed column in which a light liquid flows upwards continuously and in which a dense liquid is introduced periodically in pulses, so that it is moved downwards from plate to plate.
- a downwards pulse is not aimed at producing mixing, as ducts associated with each plate have upward and downward extensions from the plate so as make the down-coming dense liquid enter a lower body of dense liquid below rather than being caused to mix with light liquid.
- the light liquid is moved upwardly through perforations in each plate and so becomes dispersed and rises through the dense liquid above the plate.
- Another pulsed column process known to the applicant provides for liquid contacting operations in which the liquids flow counter-current in a column and flow pulses are superimposed so as to create and maintain the dispersion of droplets of one of the liquids within the other liquid.
- Plates in the column are shaped as discs and doughnuts so that liquid transfer between plates occurs through central holes and circumferential annuli in alternate plates.
- An operational cycle of the column does not allow for a no-flow settling period. As the dispersed liquid must settle or rise through the other liquid, between all adjacent pairs of plates, a throughput limit exists due to possible flooding.
- PCT/IB02/00501 describes a column with perforated plates, wherein each plate has a transfer duct that extends both upwards and downwards from the plate.
- the plates and transfer ducts emulate quite closely the common use of a downcomer in a column, for example in distillation, to facilitate the transfer of dense fluids downwards between stages in a column while light fluid is made to pass upwards through perforations in the plates or through bubble caps mounted on the plates.
- the downcomer is used to transfer dense fluids from one plate, from an overflow weir formed by the downcomer's upper end, downwards to a body of dense fluid above the plate below.
- the bottom of the downcomer forms a seal with the heavier fluid on the plate below so as to prevent any flow of light fluid up the downcomer at any time. Instead, the light fluid flows upwards through the perforations of the plate and becomes dispersed in, and rises through, the dense fluid located on top of the plate above. As the dispersed liquid must rise through the other liquid, between all adjacent pairs of plates, a throughput limit exists due to possible flooding.
- the mixing intensity possible in the column is determined by a pressure drop across the stages that can be applied to force the light fluid upwards and disperse it by the action of the perforations in the plates. This pressure drop is limited in each stage by the head of dense fluid in the downcomer as the upper level of this fluid in the downcomer reaches the level of an upper weir of the downcomer.
- US3719455 describes the simultaneous use of separate mixer and settler compartments for each stage in a complex arrangement. Use is made of a mechanical stirrer.
- the settler section operates continuously at a settling rate which is determined by the requirement of settling in each stage at the full rate of the counter-current streams.
- the throughput rate is therefore not controllable over a wide range and can be affected by flooding when settling is incomplete and mixed liquids are transferred instead of separated liquids.
- Liquid transfers take place simultaneously through two ducts and at least one of the these modes depends on the action of gravity in combination with fluid density differences. There are two main exit ports and, depending on gravity, it might not be possible to ensure that the ) exiting liquids report to the correct exit ports.
- US3549332 discloses three distinct timed sub-operations for mixing and for ) the transfers of light and heavy fluids in opposite directions.
- Inter stage ducts connect the bottom of one stage to the top of another stage so as to facilitate different transfers forwards and backwards.
- the ducts are not used for mixing.
- An object of the present invention is to provide a mixer settler column which allows for mixing, settling and counter-current transfers of fluid to be done cyclically in a plurality of distinct modes of operation. The operations of mixing, settling and transfer are carried out in different time periods in the same physical regions, instead of using different physical regions for the various operations.
- a further object of the invention is to provide a mixer settler column which can be configured and operated to implement any of a number of processes such as I liquid-liquid contacting operations, counter-current decantation, counter-current leaching, thickening, ion exchange, distillation, gas liquid contacting operations, and classification.
- the invention provides apparatus for the processing of dense and light fluids i that includes an elongate column which, in use, is vertically disposed and which has a longitudinally extending axis, a plurality of plates located at spaced intervals from one another inside the column, each plate extending transversely to the longitudinal axis, and wherein each plate includes at least one respective transfer duct with a first end attached to the plate and a second end, which is spaced from the first end, a > first aperture with a cross-section of a first area at the first end and a second aperture with a cross-section of a second area which is larger than the first area at the second end.
- a transfer duct extends upwards and downwards from a plate so as to provide for an overflow of dense fluid that moves down through the duct to join a similar dense fluid below, without mixing. Upwards flow through the duct of a light fluid is blocked and the light fluid must, instead, go through holes in the plate for dispersion into the dense fluid above.
- the transfer ducts are positioned e.g. by suitable placement of the plates so that, with respect to a first plate which is adjacent a second plate inside the column, the transfer duct or ducts
- a transfer duct in the first plate is not aligned nor in register with a transfer duct in the second plate, viewed in a longitudinal direction through the column.
- each plate forms at least part of a fluid-containing volume which J tends to trap fluid and which prevents the trapped fluid from flowing towards an adjacent plate.
- the fluid-containing volume may be formed, at least, by at least one duct, at least part of the respective plate and a portion of a wall from which the column is made. This volume may be orientated to face downwardly or upwardly (with ) reference to the respective plate) depending on the mode of operation of the column.
- each transfer duct is shaped and sized so that fluid flow at a suitable velocity through the duct from the second end towards the first end induces turbulence inside a fluid-containing volume associated with a plate adjacent the first end, and fluid flow, at a suitable fluid velocity through the transfer duct from the first end towards the second end, causes laminar or near-laminar flow of the fluid over a fluid-containing volume of the respective plate.
- the invention also extends to a method of using the aforementioned column which is orientated so that the longitudinal axis is vertical and so that, in respect of i each plate, the respective first aperture is lowermost and the respective second aperture is uppermost, the method including the steps of processing dense and light fluids in a cyclical sequence of mixing, settling and counter-current transfers.
- Mixing may be carried out for a predetermined period by introducing a fluid with a suitable flow rate into the column at or near its upper end thereby to cause a I downward flow of fluid in the column and mixing of dense and light fluids between each adjacent pair of plates within the column.
- the fluid which is introduced at the upper end may be a light fluid, a dense fluid or a mixture thereof.
- Settling may be carried out within the column, for a defined period, by the ) step of imposing a net zero flow of fluid through the column.
- bulk transfer of the light fluid within the column may be effected for a defined period by introducing fluid at a suitable flow rate into the column near or at a lower end of the column thereby to cause upward flow of only light fluid in the column while maintaining the dense fluid, ) substantially unmoved, within the respective fluid-containing volumes of the plates.
- the fluid which is introduced to the lower end of the column could be a light fluid, a dense fluid or a mixture thereof.
- the apparatus may be inverted so that the column, still in a vertical orientation, has the first apertures which are associated with the respective plates higher than the second apertures which are associated with the respective plates.
- a mixing step may be effected by introducing a fluid into the column at or near a lower end of the column.
- Settling in this mode of operation may be effected by imposing a net zero flow of fluid through the column for a defined period.
- a fluid is introduced into the column at or near an upper end of the I column.
- This fluid which may be a light fluid, a dense fluid or a combination of light and dense fluids, may be introduced at a flow rate which does not displace, to any substantial extent, fluid contained within any of the fluid-containing volumes associated with the respective plates.
- the light and dense fluids are a liquid, and a slurry of solid particles and a liquid, respectively, and the process is carried out to achieve counter- current decantation.
- fluid designates a gas, or a liquid, or a slurry of solid I particles and a liquid.
- the light and dense fluids are liquid, and a slurry of solid particles and a liquid respectively.
- the settling step and the bulk transfer step are repeated between each pair of consecutive mixing steps, with the process being aimed at thickening.
- the light and dense fluids may be liquid, and a slurry of solid particles and a liquid, respectively, and the process may be aimed at counter-current leaching.
- the process is aimed at counter-current leaching and the column is positioned between adjacent mixing tanks.
- one fluid is a liquid, or a slurry of a liquid and particles
- the other fluid is a slurry of ion-exchange beads or fibres and a liquid
- the process is aimed at a counter-current ion exchange.
- the light and dense fluids are vapour or gas, and liquid, respectively, and the process is aimed at counter-current distillation or gas-liquid contacting operations.
- the light and dense fluids are a liquid containing slow settling particles, and a liquid containing fast settling particles, respectively, and the process is aimed at counter-current classification.
- the invention also extends to a material handling process wherein, within a vertically orientated column, mixing of light and dense fluids is achieved by concurrent flow in a first direction, at suitable velocities, of the fluids through the column, settling is carried out by reducing to zero, for a defined period, the net flow of fluid through the column, and counter-current bulk transfer is carried out by directing the light fluid in a second direction opposite to the first direction through the column thereby to leave the dense fluid substantially undisturbed and within a plurality of fluid-containing volumes which are longitudinally spaced from one another within the column.
- the column provides for mixing, settling and counter-current transfers of fluid to be done cyclically, in three or more distinct modes of operation in the same physical regions, and not in different physical regions.
- the column has plates with specially shaped transfer ducts that facilitate turbulent mixing of the fluids when the flow rate is high and downwards, and that facilitate near-laminar flow of only the light settled fluid when the flow rate is relatively low and upwards.
- the plates and ducts, and possibly also the column walls, are arranged in a way that provides a containing volume in each physical stage that tends to dam the dense fluid, so that it normally does not flow downwards.
- the transfer duct attached to a plate comprises a weir which extends in one direction only, namely upwards or downwards from the plate.
- the transfer duct is not a downcomer (as referred to in the prior art) that dips below the level of the overflow of a lower plate.
- an inter-stage transfer duct is used to transport dense fluid downwards and light fluid upwards under circumstances and during time periods when settling rates impose no limit on the extent of the fluid flow rates. Any reasonable mixing intensity, for example to obtain small bubbles or droplets, is possible without the associated settling velocities having a direct effect on the counter-current flow rates.
- the flow of dense fluids downwards occurs during mixing and the flow simultaneously entrains light fluid that moves downwards too, without any need for differential flow rates to be effected by a settling mechanism.
- the flow i of light fluid upwards during a transfer period bypasses the heavier fluid and occurs when the fluids are not required to mix or to be mixed.
- the flow of light fluid upwards exceeds the downwards flow during mixing so that the net flow of light fluid is upwards.
- I rates in opposing directions, are achieved in order to facilitate mixing and bulk transfer.
- the column of the invention allows for the use of multiple plates or stages, in the column, in a parallel sense. This is achieved by making the mixing and transfer fluid movements go over more than one plate at a time.
- Prior art columns, known to > the applicant, have counter-current fluids interacting with each other similarly in each stage and it is therefore not possible to provide a facility of bypassing stages selectively to make the plates operate in parallel and so extend the throughput efficiency optimization range.
- Figure 1 is a side view in section of a mixer settler column according to one form of the invention
- Figure 2 is a side view in section and on enlarged scale of part of the column in Figure 1 , illustrating fluid flow during a mixing phase
- Figure 3 is similar to Figure 2 illustrating fluid flow during a bulk transfer phase
- Figure 4 shows the column of Figure 1 in an inverted mode for a different application
- Figures 5, 6 and 7 depict different types of transfer ducts which can be used in the column of the invention.
- Figures 8, 9, 10 and 11 are side views in cross-section illustrating different forms of the column of the invention in different applications.
- Figure 1 shows in cross-section and from one side a general structure of a mixer settler column 10 according to the invention.
- the column includes an elongate tubular body 12 with a surrounding wall 14 which encloses an elongate volume 16.
- the body has a longitudinally extending axis 18.
- An upper end 20 of the body has a dense fluid feed inlet connection 22, a light fluid return connection 24, and a light fluid outflow connection 26.
- a lower end 28 of the body has a bottom fluid return connection 30, a mixed or dense fluid outflow connection 32, and a light fluid connection 34.
- a plurality of plates 36 are provided at spaced intervals from one another at respective positions which are displaced along the longitudinal axis.
- Each respective plate has at least one transfer duct 38 which allows for fluid flow between the plates which define plate stages within the column.
- Each transfer duct has, at a first end 40 (see Figure 2), a first aperture 42 of a first area and, at a second end 44, a second aperture 46 of a second area which is greater than the first area.
- the transfer ducts can have various types of construction and Figures 5 to 7, referred to hereinafter, illustrate possibilities in this regard.
- the shaping of each duct is such that a reasonably high downward fluid flow rate in the column leads to high velocity entry and turbulent mixing in the stage below, as is shown in Figure 2. Additionally, as each duct widens in cross-section towards its upper end (the aperture 46), a reasonably low upwards fluid flow rate in the column leads to a low flow velocity and near laminar flow, of light fluid, above settled beds of dense fluid I (associated with the various plates), without causing unwanted mixing of the fluids, as is shown in Figure 3.
- Each transfer duct may be of any convenient three-dimensional shape which allows for the aperture 42 to be smaller in cross-sectional area than the second aperture 46.
- Each plate is associated with and helps to define a respective fluid- containing volume 50 which, with the column vertically orientated as in Figure 1 , is for the collection of dense fluid on the plate.
- the size of the volume is determined, at least, by the distance between the first end 40 and the second end 44 of the transfer duct. If the dense fluid level is too high, then dense fluid above the level of the
- each plate has one transfer duct.
- the plates are positioned so that successive ducts are on alternating sides of the column, as is shown in Figure 1.
- the transfer ducts, in adjacent plates are not aligned in a longitudinal sense with one another but rather are displaced circumferentially from one another.
- a plate may have one large transfer duct or multiple transfer ducts.
- Figure 5 for example illustrates two plates 36A and 36B which have opposed ducts 38A and 38B respectively, each of which extends over a circumferential arc of the respective plate.
- Figure 6 shows a plate 36C which has a plurality of funnel- shaped ducts 38C at spaced intervals over its surface. Additionally, the ducts are grouped in quadrants by means of transversely extending partitions 54 and 56 respectively.
- a plate 36D has three channel- shaped transfer ducts 38D, 38E and 38F.
- adjacent plates are orientated so that, within the column, no duct on one plate is immediately above or below a duct on an adjacent plate.
- the magnitude of the total volume of fluids introduced during the mixing phase should be adjusted to fix the required volume in the column per mass transfer stage. This could range from a fraction of a physical stage volume (i.e. the size of the volume bounded by two adjacent plates 36, extended though their respective first apertures 42, and the column wall 14) or any multiple, not necessarily an integer, of physical stage volumes.
- a fraction of a physical stage volume i.e. the size of the volume bounded by two adjacent plates 36, extended though their respective first apertures 42, and the column wall 14
- any multiple, not necessarily an integer, of physical stage volumes are used.
- the total volumes of the dense fluid feed and the light fluid return are introduced in the same ratio as is required for the contents of the main body of fluid in the column as a whole. This factor determines the volume fraction occupied by the dense fluid within a fluid-containing volume 50, rather than the size of the fluid- i containing volume.
- the ratio of dense to light fluid should not be so large as to cause a higher dense-fluid volume per stage than can be dammed by the fluid- containing volume 50 of the stage.
- the containing volume 50 would be made a reasonably high percentage of the volume of a physical stage, by increasing the distance between the first end 40 and the second end 44 of a duct, so that i operation over a wide range of fluid ratios is possible.
- a settling mode is implemented by stopping all flows into and out of the column. Sufficient time is allowed for settling to be completed or for segregation to be effected to the required extent e.g. for classification by particle size. As the plates 38 are closely spaced fast settling can take place even when ) particles, droplets or bubbles (as the case may be) are very small. The settled particles etc. accumulate in the respective fluid-containing volumes 50.
- the settling phase is followed by a bulk transfer phase.
- a volume of the light fluid would have been moved into and down the column together with the dense fluid.
- a similar volume of fluid, drawn or extracted from the mixed fluid outflow at the connection 32 should be returned to the bottom of the column via the return 30 so that the light fluid is pushed back up the column to its position before mixing.
- Fresh light fluid is fed through the connection 34 to produce an additional upward movement so that the light fluid has a j net upward flow over the full operational cycle.
- the light fluid In the main body of the column the light fluid, above each respective settled bed of dense fluid in the respective volumes 50, is moved upwards in near laminar flow by the moderate flow rate of a required volume of fluids into the bottom of the column.
- the light fluid feed at the connection 34 and the bottom fluid return at the ) connection 30 are made to enter the column at low to moderate flow rates. These flows can occur simultaneously or consecutively, preferably with the light fluid feed entering through the connection 34 after the bottom fluid return.
- Figure 3 illustrates near laminar flow 60, for the bulk transfer of the light fluids in the column, which is induced by low fluid velocities. Ideally the near laminar flow 60, for the bulk transfer of the light fluids in the column, which is induced by low fluid velocities. Ideally the near laminar flow 60, for the bulk transfer of the light fluids in the column, which is induced by low fluid velocities. Ideally the near laminar flow 60, for the bulk transfer of the light fluids in the column, which is induced by low fluid velocities. Ideally the near laminar
- the flow rate of the light fluid during bulk transfer should be set carefully to regulate or minimize the degree of mixing between the light and dense fluids.
- the mixed fluid outflow at the connection 32 should preferably be settled so as to produce a light fluid to be returned to the bottom of the column (via the connection 30) and a dense fluid product.
- the bottom of the column can have features to facilitate this, or the separation can be done using a suitable external processing unit such as a thickener.
- the separation of the light and dense fluids at an end of the column, where a return flow is required, is best done within the end of the column, so that no mixed light and dense fluids leave the column and so that there is no need to separate the mixed fluids externally.
- the transfer ducts of one or more plates at the end of the column might be made wide and without any narrow aperture, or i made to be just relatively large holes in the plates, so that further mixing tends not to occur there and so that those plates only serve to facilitate settling.
- an external separator such as a thickener might be better.
- the normal, or the inverted, version of the column (i.e. Figure 1 or Figure 4) can be used for liquid-liquid contacting operations.
- the ratio of light to dense liquid volumes in the column is required to be close to unity, the two orientations of the column tend to favour dense, and light continuous-phase liquids, respectively, otherwise the liquid of higher volume would tend to become the continuous-phase liquid during settling.
- the orientation of the column should be normal or inverted, respectively, to facilitate good liquid dynamics during the bulk transfer mode of operation.
- Figure 8 illustrates an example of customisation of the column for liquid- liquid contacting operations.
- the bottom of the column can conveniently be used to provide for separation of the dense and light liquids so that the bottom liquid return is separated dense liquid that pushes light liquid up the column.
- a buffer volume 61 can be allocated to allow for the reverse-flow volume of the light liquid during mixing, and for excess light liquid there to overflow and to leave the column. Counter-current decantation
- Figure 9 illustrates an example of customisation of the column for counter- current decantation.
- the average slurry density in the column is made to be the same as that of the slurry feed, so there is no light fluid return at the top of the i column.
- solids from the process are required to be thickened to a density much higher than that of the slurry feed, and a thickener is used downstream of the column to thicken the solids and provide a recycled thickener overflow that serves as the bottom fluid return.
- an upstream thickener can be used to thicken the feed slurry before it enters the column, in which case a downstream thickener
- the column can be used to connect a pair of stirred leach reactors so as to transfer solids from a first tank to a second tank and liquid from the second tank to the first tank.
- the column needs to have only one pipe connected at each of the two ends as shown in Figure 10. Liquid is pumped slowly from the top of the column to the first tank 62, with one or more breaks in pumping for settling if necessary, to ensure that only clear liquid leaves the top and solids are retained on the plates. Slurry from the first tank 62 is pumped at a fast rate into the top of the column, causing the settled solids in the column to be mixed with the slurry and to move downwards towards the connection to the second tank 64.
- the mixing flow should push the contents of the column downwards by less than the full volume of the column, for example half of the volume, to give approximately two mass-transfer stages of counter-current decantation.
- a particular feature of the operation of the column is that sets of adjacent plates can effectively be made to operate in parallel, thus allowing a trade-off between throughput capacity and the number of mass-transfer stages. This is done dynamically simply by changing the volumes of fluids transferred upwards and downwards during the operating cycles.
- This versatility allows a tall and thin column, with many plates, to be operated quite similarly to a shorter and wider column with fewer plates and the same total plate surface area, Because bulk counter-current movement of streams is not required during mixing or settling, the column can operate with small particles, droplets or bubbles, with good mixing and with efficient settling, without necessarily limiting throughput.
- the column of the invention can be used for liquid- liquid contacting operations as well as several other processes, by customization of the time-delimited modes.
- the column can be used for counter-current decantation, with many stages of washing, less dilution and lower costs than with multiple conventional thickeners. Thickening in the column can be achieved by multiple sub- cycles of slurry feeds and settling periods, with the build-up of solids on the plates and the displacement of clear liquid upwards, and then a downwards mixing flow to drive the thickened pulp downwards.
- Ion exchange and leaching operations in the column can in some cases be very effective, particularly when the rate-limiting step of mass transfer tends to be diffusion, or reactions, within resin or solid particles.
- the column Under well-controlled conditions, the column can be used to do counter-current, multi-stage classification of solid particles based on their settling velocities.
- the column does not have the problem of counter-current fluid streams needing to pass each other in each physical stage by the rise or fall of particles, droplets or bubbles of one fluid through the other continuous fluid. Larger counter-current flows are effected simply by larger fluid transfers per operational cycle, independently of the settling part of the process.
- the versatility of the column provided by the degrees of freedom available for its operation allows a single column with standard plates to be used for any of a number of processes, and at any of a wide range of operating conditions.
- Three distinct process operations namely mixing, settling and transfer, in a time cycle, are carried out in the same place in the column in simple stages and with no internal moving parts.
- Of importance in the present invention is the step of making one or both of the transfers induce mixing to eliminate the need for a separate mixing step.
- the column also has the advantage of providing for essentially instantaneous shutdowns and instantaneous restarts after any reasonable length of delay, with no process disruption, by freezing the column's operation in the settling phase.
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2875600A CA2875600A1 (en) | 2012-05-02 | 2013-04-30 | Mixer settler column |
AU2013255986A AU2013255986B2 (en) | 2012-05-02 | 2013-04-30 | Mixer settler column |
AP2014008094A AP4050A (en) | 2012-05-02 | 2013-04-30 | Mixer settler column |
ZA2014/08728A ZA201408728B (en) | 2012-05-02 | 2014-11-27 | Mixer settler column |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ZA201203142 | 2012-05-02 | ||
ZA2012/03142 | 2012-05-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2013166528A1 true WO2013166528A1 (en) | 2013-11-07 |
Family
ID=48748569
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/ZA2013/000029 WO2013166528A1 (en) | 2012-05-02 | 2013-04-30 | Mixer settler column |
Country Status (5)
Country | Link |
---|---|
AP (1) | AP4050A (en) |
AU (1) | AU2013255986B2 (en) |
CA (1) | CA2875600A1 (en) |
WO (1) | WO2013166528A1 (en) |
ZA (1) | ZA201408728B (en) |
Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1741519A (en) * | 1926-12-10 | 1929-12-31 | Universal Oil Prod Co | Dephlegmator or fractionating column |
US2228434A (en) * | 1938-06-04 | 1941-01-14 | Standard Oil Dev Co | Solvent extraction process |
US2609277A (en) * | 1947-02-24 | 1952-09-02 | Phillips Petroleum Co | Contacting of immiscible liquids |
US2665196A (en) | 1952-10-20 | 1954-01-05 | Dow Chemical Co | Multistage internal mixer-settler extraction apparatus |
US2937078A (en) | 1956-02-03 | 1960-05-17 | Atomic Energy Authority Uk | Mixer-settler apparatus |
US3108859A (en) | 1959-12-15 | 1963-10-29 | Oscar H Koski | Pulsed extraction column |
US3325255A (en) | 1963-09-17 | 1967-06-13 | Robert E Treybal | Liquid extractor |
US3389969A (en) | 1964-02-18 | 1968-06-25 | Hoffmann La Roche | Countercurrent liquid-liquid extraction apparatus |
US3549332A (en) | 1969-01-13 | 1970-12-22 | Upjohn Co | Countercurrent liquid-liquid extraction device |
US3719455A (en) | 1970-07-21 | 1973-03-06 | Shionogi & Co | Mixer-settler extractor |
US3804594A (en) | 1970-09-09 | 1974-04-16 | Kemira Oy | Apparatus for liquid-liquid extraction |
US3979281A (en) | 1974-12-16 | 1976-09-07 | Universal Oil Products Company | Continuous liquid extraction process with periodic flow of the denser stream |
US3984331A (en) | 1974-09-09 | 1976-10-05 | Holmes & Narver, Inc. | Liquid-liquid settler used in solvent extraction apparatus |
US3989467A (en) | 1974-05-24 | 1976-11-02 | Holmes & Narver, Inc. | Apparatus for contacting immiscible fluids |
US4247521A (en) * | 1979-08-15 | 1981-01-27 | Union Carbide Corporation | Liquid-liquid contacting system |
US4541724A (en) | 1983-07-29 | 1985-09-17 | Shell Oil Company | Apparatus for counter-current contact of fluids |
EP0238136A1 (en) * | 1986-03-20 | 1987-09-23 | Shell Internationale Researchmaatschappij B.V. | Extraction process |
US5194152A (en) | 1989-07-20 | 1993-03-16 | Richter Gedeon Vegyeszeti Gyar Rt. | Apparatus to contact liquids of different density |
WO2002049736A1 (en) | 2000-12-18 | 2002-06-27 | Ineos Fluor Holdings Limited | Apparatus and method for extracting biomass |
-
2013
- 2013-04-30 CA CA2875600A patent/CA2875600A1/en not_active Abandoned
- 2013-04-30 AU AU2013255986A patent/AU2013255986B2/en not_active Ceased
- 2013-04-30 AP AP2014008094A patent/AP4050A/en active
- 2013-04-30 WO PCT/ZA2013/000029 patent/WO2013166528A1/en active Application Filing
-
2014
- 2014-11-27 ZA ZA2014/08728A patent/ZA201408728B/en unknown
Patent Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1741519A (en) * | 1926-12-10 | 1929-12-31 | Universal Oil Prod Co | Dephlegmator or fractionating column |
US2228434A (en) * | 1938-06-04 | 1941-01-14 | Standard Oil Dev Co | Solvent extraction process |
US2609277A (en) * | 1947-02-24 | 1952-09-02 | Phillips Petroleum Co | Contacting of immiscible liquids |
US2665196A (en) | 1952-10-20 | 1954-01-05 | Dow Chemical Co | Multistage internal mixer-settler extraction apparatus |
US2937078A (en) | 1956-02-03 | 1960-05-17 | Atomic Energy Authority Uk | Mixer-settler apparatus |
US3108859A (en) | 1959-12-15 | 1963-10-29 | Oscar H Koski | Pulsed extraction column |
US3325255A (en) | 1963-09-17 | 1967-06-13 | Robert E Treybal | Liquid extractor |
US3389969A (en) | 1964-02-18 | 1968-06-25 | Hoffmann La Roche | Countercurrent liquid-liquid extraction apparatus |
US3549332A (en) | 1969-01-13 | 1970-12-22 | Upjohn Co | Countercurrent liquid-liquid extraction device |
US3719455A (en) | 1970-07-21 | 1973-03-06 | Shionogi & Co | Mixer-settler extractor |
US3804594A (en) | 1970-09-09 | 1974-04-16 | Kemira Oy | Apparatus for liquid-liquid extraction |
US3989467A (en) | 1974-05-24 | 1976-11-02 | Holmes & Narver, Inc. | Apparatus for contacting immiscible fluids |
US3984331A (en) | 1974-09-09 | 1976-10-05 | Holmes & Narver, Inc. | Liquid-liquid settler used in solvent extraction apparatus |
US3979281A (en) | 1974-12-16 | 1976-09-07 | Universal Oil Products Company | Continuous liquid extraction process with periodic flow of the denser stream |
US4247521A (en) * | 1979-08-15 | 1981-01-27 | Union Carbide Corporation | Liquid-liquid contacting system |
US4541724A (en) | 1983-07-29 | 1985-09-17 | Shell Oil Company | Apparatus for counter-current contact of fluids |
EP0238136A1 (en) * | 1986-03-20 | 1987-09-23 | Shell Internationale Researchmaatschappij B.V. | Extraction process |
US5194152A (en) | 1989-07-20 | 1993-03-16 | Richter Gedeon Vegyeszeti Gyar Rt. | Apparatus to contact liquids of different density |
WO2002049736A1 (en) | 2000-12-18 | 2002-06-27 | Ineos Fluor Holdings Limited | Apparatus and method for extracting biomass |
Also Published As
Publication number | Publication date |
---|---|
AP2014008094A0 (en) | 2014-11-30 |
AU2013255986A1 (en) | 2014-12-18 |
ZA201408728B (en) | 2015-11-25 |
AP4050A (en) | 2017-03-02 |
AU2013255986B2 (en) | 2017-08-03 |
CA2875600A1 (en) | 2013-11-07 |
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