DE1139816B - Device and method for bringing a liquid phase into contact with two or more further phases in countercurrent - Google Patents

Description

GERMAN

PATENT OFFICE

N16597 IVa / 12g

REGISTRATION DATE: APRIL 21, 1959

NOTICE
THE REGISTRATION
AND ISSUE OF THE
EDITORIAL: NOVEMBER 22, 1962

The invention relates to a device for bringing a liquid phase into contact with two or more further phases in countercurrent with a preferably vertical tube and a shaft arranged therein, on which centrifugal disks are axially spaced apart and at right angles to the shaft are arranged.

The phases to be brought into mutual contact are flowable phases, especially in both cases around liquid phases or on the one hand around liquid and on the other hand around gaseous Phases. One of the phases can also be a finely divided or divided solid substance or a contain such substance.

Mixing devices are already known in which two phases are mixed to form a product should; in these known devices, a rod is provided within a tube which are arranged at an axial distance and at right angles to the rod net disks, which by means of the rod are axially movable up and down.

It is also already a device for bringing one liquid phase into contact with two or several other phases known in countercurrent, in which the inner wall of the tube with stator rings is provided, which are arranged approximately in the middle between two adjacent rotor disks. These stator rings guide the flow in such a way that the flow of the contained in the tube Medium reverses its direction of movement near the pipe wall and flows back to the axis of the pipe. In this way the desired course of the vertebrae is maintained, and also becomes a immediate or unhindered further conveyance of the medium over a noticeable distance in the direction the pipe axis prevents. However, this known device has the disadvantage that the stator rings must be arranged in a precisely defined position.

There are already packed columns with perforated disks reaching up to the column wall known, in which these disks are only moved so that no centrifugal effect occurs. As a result, in these known packed columns in which the packing is a substantial part the column makes up that the trickling down liquid with gas scrubbing or the Liquid is distributed more or less evenly over the cross-section during extraction and the Liquids do not always find the same path with the least resistance.

It is the object of the invention to provide a simple and effective device for contacting

Apparatus and method

for bringing a liquid into contact

Phase with two or more others

Countercurrent phases

Applicant:

Bataafse Petroleum Maatschappij NV,
The hague

Representative: Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse and Dipl.-Chem. Dr. rer. nat. E. Frhr. v. Pechmann, patent attorneys, Munich 9, Schweigerstr. 2

Claimed priority:
Netherlands of April 23, 1958 (No. 227 128)

Frederik Johannes Zuiderweg,

Amsterdam, Netherlands),
has all been called the inventor

Bringing a liquid phase with two or more other phases in countercurrent to create. Based on a known device for bringing a liquid phase into contact with two or more further phases in countercurrent with a preferably vertical tube and a shaft arranged therein, on which centrifugal disks are arranged axially at a distance from and at right angles to the shaft, the centrifugal disks are dimensioned according to the invention in such a way, that they extend almost to the inner wall of the tube and there is a narrow annular gap between the disks and the tube wall and the centrifugal disks have openings of at least 1 to 2 cm ² , the total area of which is 30 to 50% of the total area of the centrifugal disks, the tube having a diameter of at least 15 cm. Despite the absence of the stator rings, it is found that there is no undesired or immediate or unimpeded further conveyance of the medium in the tube over noticeable axial distances. Otherwise, the vortices are generally formed in a manner similar to that in the known device mentioned above. By eliminating the stator rings, the assembly of the device is significantly simplified.

In practice, the area of the slot or gap is usually about 10 ^fl / o or less for large size devices

209 708/322

3 4

Cross-sectional area of the pipe. In the case of a large set-up phase with one or more further phases in the line, the pipe diameter is about 100 to countercurrent in a device according to the invention about 300 cm. The smallest diameter is about ^1, preferably the sling discs 15 cm; In general, such a speed of rotation can be given at smaller throughputs that a

knives do not achieve good dispersion. 5 or more of the phases over the entire length of the

The openings in a rotor disk, together with the section of the disk containing the centrifugal disks

i have the same shape and size, but the pipe can remain distributed in the form of a dispersion or

They also differ in terms of their shape and / or stay.

Differ in size. The same applies to the opening The device according to the invention makes it possible

voltages in the various centrifugal discs. The io two phases in intimate contact with each other

Total area of the brought forward in a slinger in order to z. B. Mixtures of liquids with the help

The openings seen need not be extracted at all of the selective solvents. Such

Slices to be the same, but the area extraction can be carried out at atmospheric pressure

the contents of the openings in the individual panes can be controlled; an example of this is extraction

nen z. B. according to the local liquid 15 of lubricating oil with furfural for the purpose of removal

exposure to aromatic substances at various points on the pipe. The extraction leaves

differentiate. Furthermore, the openings can be carried out inside, but also at increased pressure,

half the area of the disc concerned regularly what z. B. is necessary when aromatic substances

or be irregularly distributed. Luminous kerosene with HiMe of sulfur dioxide

The individual openings in the panes should be removed 2 °. Under these circumstances, the be large that the droplets of the dispersed phase rotor shaft instead of directly acting mecha, when the disks are rotated, the opening devices are magnetically attached can happen; the passing of the drifts as it is z. B. with an engine liquid or gaseous non-dispersed phase an enclosed rotor is the case. Further offers no difficulties. The middle diameter can be reached with the help of a shaft in the tube The diameter of the openings is therefore at least several built-in turbines, which drive their drives Millimeters and in general even several energy levels are taken from one of the phases supplied. Centimeter. Furthermore, the diameter of the opening is also important. However, it can also be used with increased pressure preferably greater than the thickness of the devices concerned, generally expedient, the slinger and is usually even 30 to drive the shaft directly, e.g. B. with HiKe at least a multiple of this thickness. an electric motor.

Each centrifugal disk preferably has in the The device can also be in advantageous proximity their outer edge, on average, one way of carrying out chemical reactions Use a smaller opening area than near the rotor, e.g. B. for the production of isopropyl alcohol wave. This can be z. B. achieve that 35 propylene and sulfuric acid, all openings are in the vicinity of the rotor shaft. so that the rotor disk in the vicinity utilize those in which the phases supplied are solid their outer edge by a non-opening substances are contained. This applies e.g. B. for the Abtrengen provided ring is formed. one or more components from one

It may occasionally be useful to mix the slots 40 with the aid of adsorption; in this case between the pipe wall and the rotor disks at the mixture forms one phase, while one the different disks with different widths of finely divided adsorbent the other phase do; for example, the width of the slots can form. An example of this application is or gaps in the successive rotor - the separation of a mixture of paraffins and iso disks be alternately larger and smaller. In- 45 paraffins or an alcohol-water mixture with consequently, the strength of the vortex flow is ort-help molecular sieves, z. B. in the form of zeolites, borrowed be larger, so that under certain conditions one can also use the facility in a similar way conditions to use a better exchange of components in ion exchange processes, can be achieved between phases. One of the phases can consist of a suspension of a

In practice, the cross-section of the tube and 50 solid matter consists of a liquid. This is

the outline of the rotor disks is circular or, for example, when washing and possibly when

approximately circular. The diameter of the tube neutralizing mother liquor from a crystalline

does not need a mass of the case over the entire length of the pipe. For example, the

to be uniform, yet one will generally make a manufacture of potassium nitrate from potassium chloride and

Provide a pipe with a uniform diameter. 55 nitric acid a suspension of potassium nitrate

The distances between two successive crystals in an acidic mother liquor; these crystals the rotor disks do not all need the same size by means of a countercurrent treatment to be. However, it is preferred to use at least one auxiliary agent containing an alkali hydroxide of the panes should be cleaned of liquid at equal intervals. The suspension is on other to be arranged along the pipe axis. Appropriate 60 fed to the top of the device while the Values for these distances B. takes place between 5 and supply of the auxiliary liquid at the lower end; 50% of the pipe diameter. The rotor shaft can be at the bottom of the purified crystals have a relatively small diameter; Device in the form of a suspension in the auxiliaryyour Cross-sectional area makes no more than 10% liquid released.

and generally no more than about 5% of the 65 die in the device of the present invention in free Cross-sectional area of the pipe. phases to be brought into mutual contact

When carrying out a method for relating to their specific weight

Stirring a continuous liquid sheath. The lighter phase will be on the lower end

fed to the device while the heavier phase is introduced at the top. During the In contact there is an exchange of material between the phases; occasionally, d. H. at a chemical Reaction, new substances are formed. During the touch, one of the phases is continuously in the other phase dispersed, so that it is in the invention Establishment does not depend on whether a set of consecutive mixing and Settling rooms are available. The droplets of the dispersed phase either close at the top or together again at the lower end of the tube so that they form a continuous phase, and depending on whether the dispersed phase is lighter or heavier than the undispersed phase. This confluence can, however, also occur exclusively or essentially exclusively outside of the pipe in a separate separation vessel. In many cases it is beneficial to have a solid Grid or a perforated plate or the like, which is usually supported by a ring, in the upper part of the tube above the heavy phase inlet and / or in the lower part of the tube below of the inlet for the lighter phase to allow the dispersed phase to flow together better to achieve or an undesirable mixing of the introduced phase to be dispersed and the to prevent non-dispersed phase to be discharged.

Furthermore, the device according to the invention can be used to carry out an extraction with the aid of perform two solvents. In this case, the mixture to be separated is at a certain Point fed between the top of the device and the bottom thereof; the extraction solvents are initiated at opposite ends of the facility. An example for One such extraction process is the treatment of essential oils with pentane and alcohol.

If more than two phases are dealt with, there is one phase in which the other phases are dispersed.

At the lower end of the device, the rotor shaft runs in a bearing or it is supported by the bearing held in place. It can happen that the bearing is affected by a corrosive medium which may also be a bad lubricant, while one of those to be introduced Phases does not have these disadvantages. In these circumstances, it is appropriate to set up a preferably small flow of the non-corrosive resp. to supply a phase that is less corrosive or acts as a better lubricant. This Current can be branched from the current of the lighter or the heavier phase, depending on the circumstances will.

When extracting lubricating oil with furfural one can e.g. B. a part of the to be extracted Use lubricating oil, which is the light phase, as the lubricant, since that surrounding the bearing The extract phase has a corrosive effect. When removing asphalt from heavy fuel oil with the help of propane one can direct a small part of the heavy oil forming the heavy phase to the camp, there it has better lubricating properties than the asphalt phase located in the lower part of the facility.

The invention is illustrated below with reference to schematic drawings of an exemplary embodiment explained in more detail.

Fig. 1 shows an embodiment of a device according to the invention, which is a vertically arranged Rohrl includes, which is provided with a feed line 2 for the heavier phase, which in the Countercurrent to be brought into contact with the lighter phase, which is via a pipe 3

ίο is supplied. Each of these lines 2 and 3 can open into the pipe 1 via a manifold having a plurality of inlets. Furthermore, the Rohrl an outlet line 4 for the light phase and an outlet line 5 for the heavy phase. Along the Center line of the tube 1 extends a relatively thin rotor shaft 6. This shaft is with her The upper end is suspended in a bearing 7 and runs with its lower end in a bearing 8. The rotor shaft 6 carries a plurality of rotor disks 9, each provided with openings 10; with the one shown Embodiment, the openings are more or less evenly over the area of the relevant Disk distributed. The disks are generally flat plates that attach to the shaft are attached and extend perpendicular to the center line of the shaft. Between each rotor disk 9 and the inner wall of the tube 1 has a relatively narrow slot 11. The pipe 1 can be provided with heating or cooling means, e.g. B. with a suitable jacket or a hollow rotor shaft as well as with hollow rotor disks; however, this form of training is shown in the drawing not shown.

The following describes the operation of the device in connection with an extraction process describes how to remove aromatic substances from lubricating oil with the help of furfural. That, here the Furfural which forms the heavy phase is fed in via line 2, while the furfural which forms the light phase Lubricating oil is supplied via line 3. A small part of the lubricant flow is over branched off a line 12 and fed to the lower bearing 8 in order to lubricate it. With that in mind a hood 13, which encloses the bearing 8, is attached to the rotor shaft. The branched off lubricant flow is of course kept as small as possible.

The furfural is the dispersed phase that flows through the column in the form of Droplets moving down; the droplets, which are furfural in which the aromatic substances are dissolved, collect at the bottom the column and form a coherent liquid phase there, which the device on the Line 5 leaves. The interface between the phases is in the lower part of the tube 1 at 14, and it is kept at the indicated level by the speed of the feeding and removal of the individual phases is selected in a suitable manner.

A wide-meshed grid 15 is arranged between the inlet opening 3 and the separating surface 14, which is attached to and held by a ring 16. This will cause turbulence to occur at the interface of the phases prevented, and the undisturbed coalescence of the droplets is supported. A similar combination of a grille 17 with a ring 18 is between the inlet port 2 and the outlet line 4 arranged,

The total area of the openings was 50% of the total Disc surface.

In order to determine the maximum permissible load on the facility, two phases, which do not differ or let them mix with one another only to a small extent, in the present case Water and kerosene, passed through the facility in countercurrent. In this case that formed Water the heavy phase, in which the lighter one

to support an undisturbed exit of the light phase. That freed from the aromatic substances extracted lubricating oil is withdrawn at 4 and the extract phase, i.e. H. that the aromatic Furfural containing substances is withdrawn from the facility at 5.

ESe rotational speed of the rotor disks is set so that one of the phases, in the present Fall the furfural phase, in the form of a dispersion

within the whole column, but of course with i & kerosene was dispersed. Except for the upper and lower sections, when exposed to an amount of water of

remains distributed. As a result, there is no 1 m ³ per hour and an amount of kerosene of

At ³ per hour and a rotor shaft speed of 100 revolutions per minute, there was still no flooding. The size of the droplets of the dispersed. Phase was about 1 to 2 mm. The flooding limit was reached at a speed of 125 revolutions per minute with a load of water of

can be produced, as indicated in Figure 1; zo 2 m ³ per hour and, a quantity of kerosene from this vortex formation is due to the rotation of the 2 m ³ per hour, the flooding limit was at

Difficulties from an alternating mixing of the phases, upon which a settling of the dispersed Phase follows.

Regarding the general operation of the facility, it should be noted that in each department, the bounded by two adjacent disks, a system of two toroidal vertebrae traced back. The eddies both revolve around the rotor shaft in the same direction, and although on the right side of Fig. 1 to the rear, as indicated by a cross, and as on the left side forward, as indicated by a dot. They also rotate Eddy in the planes containing the rotor shaft. This rotational movement of the vertebrae, which z. B. also in the Drawing plane occurs, is indicated in Fig. 1 by arrows, and it can be seen that these rotational movements are directed in opposite directions.

The two phases move in countercurrent through the device, and during this movement constantly go parts of the comparatively difficult phase, which in the present case is the Extraction of lubricating oil with furfural is about furfural droplets, from a higher lying vortex into an underlying eddy, while parts of the comparatively light phase in this one Fall continuously from one vertebra at a lower level to one above it Trespassing vertebrae.

The transfer of the material, i.e. H. in the present The case of the exchange of components between the phases is mainly due to the intimate contact between the phases in the vortices and when passing through the openings in the rotor disks.

A particular embodiment of a rotor disk 9 is shown schematically in FIG. 2. These Disc has four openings 10, all of which are located in the center of the tube; near the edge the disk 9 no openings are provided. In the illustrated embodiment, the openings the shape of circular sectors. However, it is also possible to have a different number of openings as well Provide openings of a different shape.

To give an example, it should be mentioned that in a device executed according to FIG The diameter of the pipe 1 was 30 cm. In the tube there were nine disks about mm and a diameter of 29 cm at regular intervals of 12 cm. Every The disk had fifty-four openings with a speed of 75 revolutions per minute achieved; in this case the size of the droplets of the dispersed phase was less than 3 mm.

In all of the above cases, the water dispensed was essentially kerosene free, and the removed kerosene was also essentially free of water.

Claims (3)

PATENT CLAIMS: 1. A device for bringing a liquid phase into contact with two or more other phases in countercurrent with a vertical tube and a shaft arranged therein, on which centrifugal disks are arranged axially at a distance and at right angles to the shaft, characterized in that the centrifugal disks (9) such are dimensioned so that they almost reach the inner wall of the tube (1) and between the disks (9) and the tube wall (1) there is a narrow annular gap (11) and the centrifugal disks (9) have openings (10) of at least 1 to 2 cm ² , the total area of which is 30 to 50% of the total area of the centrifugal disks (9), the tube (1) having a diameter of at least 15 cm. 2. Apparatus according to claim 1, characterized in that each centrifugal disk (9) in in the vicinity of its outer edge has, on average, a smaller opening area than in the Near the shaft (6). 3. Method of countercurrent to a continuous liquid phase in a facility according to spoke 1 and 2 with one or more further phases in contact, thereby characterized in that the centrifugal disks are given such a rotational speed that one or more of the phases over the entire length of the one containing the slinger discs Section of the pipe can be distributed in the form of a dispersion. Documents considered: German Patent Nos. 521541, 566 945, 2.5 cm diameter- These openings were 65 877136;
Evenly distributed over the disc surfaces. U.S. Patent Nos. 2223,348, 2391110. 1 sheet of drawings © 209 708/322 11.62