FI118630B - Method and apparatus for treating solutions - Google Patents

Description

118630 METHOD AND APPARATUS FOR SOLUTION SOLUTION.

The present invention relates to a method for treating solutions according to the preamble of claim 1, in particular to an apparatus based on the use of an ion exchange resin, and to an apparatus according to the preamble of claim 6 for applying the method.

A commonly used ion exchange apparatus is known as an ion exchange column and typically consists of a vertical cylindrical pressure vessel. The column is typically half-filled, i. usually a layer 1 to 2 m thick, loosely packed with a spherical ion exchange resin onto which the solution to be treated is led. The solution passes through the resin layer and exits when treated through one of the bottom 15 of the column.

An empty space at the top of the column is necessary because of the resin space during use. the degree of change usually changes slightly. In addition, the empty space is also required for the resin !!!!: regenerative or cleaning, where the * · 20 cleaning fluid applied in the opposite direction fluidizes the resin layer and the broken resin particles can be removed by overflow.

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The resin layer causes a flow resistance which causes the fluid to be treated to pass under pressure through the resin bed. The pressure must be high enough to provide the necessary flow rate. On the other hand, excess pressure can compress the resin layer to increase flow resistance and reduce flow rate:.

The resin used in such a column is typically spherical with a particle size of about 0.5 to 1.2 mm, with a minimum of about 0.3 mm. The large spherical size allows for a low specific flow resistance, but on the other hand the resin bed must be * «..... thick to achieve an effective cleaning effect. A thick layer of resin 2 118630 is also required to avoid ducting, since due to the large volume change of the resin during use, the fluid to be cleaned tends to form channels instead of steady flow, thereby substantially reducing the cleaning effect.

5

The cleaning effect of the above structure is not very good if large organic molecules or colloidal inorganic compounds have to be removed from the solution. Namely, they do not fit into the pores of the spherical resin or their diffusion in the pores is slow. Such a structure is also ineffective when the concentration of excipients in the solution is low.

A solution is also known in which a thin layer of powdery ion-exchange resin is formed on the vertical tubular elements in the pressure vessel. In such an arrangement, the solution to be cleaned can be passed through the resin bed at a high flow rate without too high a pressure drop. However, such a solution requires a continuous flow of liquid through the resin layer because, as the pressure exerted by the flow is removed, the resin layer ·: · leaks off the surface of the elements.

* • * * · - •: Y-20 It is known that the filtering of finely divided particles creates channels in the filter cake through which a significant part of the filtrate is removed from the cake without being purified. In particular, if the filter cake t t · '... · gets dry, the risk of channeling is particularly high, and in the case of ion exchange resins, it must be noted that the resin particles shrink and swell during use, which increases channeling and edge leakage.

• · • * · / One known solution to avoid powder resin channeling is vertical. this filtering element is to mechanically compress the ion exchange resin layer.

• · ·: ... This has the disadvantage of having too high and uneven bed densities.

It is an object of the present invention to overcome the drawbacks described above and to provide *: * ·: a space-saving device for handling large volumes of liquid based on the use of a small 3118630 ion exchange resin. Here, the flow can be stopped and restarted without the channeling described above occurring.

This object is achieved by the method according to the invention and by a device 5 in which the horizontal filtering elements are superimposed in a pressure-resistant sealed container. According to the invention, a thin layer of about 10-100 mm, typically 10-40 mm thick, powdered ion-exchange resin, having a particle size in the range of 1 to 300 µm, typically 10-300 µm, is formed on the upper surface of the filtering elements, with a flexible flow-10 partitioning resin layer prevent it.

The features of the solution according to the invention are more specifically described in the characterizing parts of the appended claims.

The invention will now be described in more detail with reference to the accompanying drawings, in which:

Fig. 1 is a cross-sectional view of an apparatus according to the invention, Fig. 2 illustrates a construction of a cleaning element according to the invention, Fig. 3 shows the filtration result of an aqueous solution containing a foaming chemical,

Figure 4 shows the dry matter content and t · · · * · · · · · · · · · · ··· of a hexane-based process solution. test the ash composition.

• * - * · ··· '***, An apparatus according to the invention consists of a pressure-resistant • · * ·! 30 containers (1), the upper part of which is to be cleaned through the inlet (2).

"*** At the bottom of the tank (1) is a pipe (3) through which the solution which has passed through the cleaning elements (4) is discharged cleanly outside the tank (1). The tank (1) also has a flange, bayonet or similar connection (11). 5), which allows the container to be opened for maintenance, replacement of the elements (4), or for other purposes.

At the bottom of the container (1) is a support tube (6), from which the cleaning elements (4) are stacked 5 in succession into a continuous series (7). Suitable dimensions of the elements (4) achieve a sufficient lifetime stability of the set (7), but the elements (4) can also be supported, for example, on the walls of the container (1). A baffle plate (8) is placed above the array of elements (7) to control the inlet flow, which allows for an even distribution of the inlet flow to all cleaning elements (4).

10

Figure 2 shows a construction of a suitable cleaning element. The center tube (9) of the element (4) consists of an inner tube (10) and an outer tube (11) which are dimensioned so that an integral series (7) of elements (4) can be assembled with the tube (10) of the adjacent element (4). in.

15

In the center tube (9) formed by the tubes (10) and (11), there is attached an element bottom plate (12) having a vertical wall (13) at its outer edge. On the bottom plate * j · (12) there is a grille (14) which supports the fabric (15) allowing vertical ·: ··. flow of liquid through the fabric (15) onto the base plate (12) and further through the openings Y · 20 through the openings (16) into the center tube (9).

· "·· - ·, * ·" The inner edge (17) and outer edge (18) of the grille area are impermeable to liquid, • v .: to prevent the liquid to be cleaned from ducting adjacent the vertical walls of the element.

25

A layer of powdered ion exchange resin (19) is packed on the fabric (15). The optical thickness of the * * resin layer is determined by the particular resin grade and color. warping, but typically has a layer thickness of 10-40 mm. Can * ·· gas (15) is most preferably a filter cloth or, alternatively, a nano or micro filtration membrane.

* · »··· • · 5 118630

A fabric or other sheet (20) is provided on top of the resin layer (19) for the purpose of acting as a flow divider and providing a resilient support to the resin layer (19). The fabric (20) can thus compensate for changes in the volume of the resin (19) and prevent channeling of the fluid flow. The fabric (20) 5 also prevents the resin layer (19) from being washed away with the fluid flow.

The fabric (20) can be secured to the resin layer (19) at its edges, for example, by means of rings (21) and (22) which are locked in place by means of, for example, sockets (23). The underside of the tires may have protrusions, grooves, etc. for securing the fabric (20) in place.

In the exemplary embodiment, the inner tube (10) is shorter than the outer tube (11), whereby when the elements are stacked, the openings (16) remain open with the outer tube (11) supported by the element bottom plate (12) ).

For filtration, the container (1) is opened from the flange (5) and the required number of filter elements (4) are stacked on top of each other starting from the support tube (6). At the top, a baffle plate (8) is arranged with the lower end of the central tube shaped similar to the inner tube (10) of the cleaning element (4), thereby closing the upper end of the filtration channel formed by the central tube (9). The tank (1) is then closed.

9 · · • · *: * * The actual filtration process can be started by filling the tank (1) with the liquid to be cleaned through the inlet • • - (2). Since at least a portion of the resin layer (19) is resin ground according to the invention, its flow resistance is reasonably high. Therefore, the liquid to be purified begins to flow significantly through the resin layer V ·; only when the reservoir (1) is filled with liquid to be cleaned and the reservoir has sufficient * ··. this pressure. There may also be a valve (25) at the top of the tank (1) through which the air remaining in the tank may be removed. The valve (25) also allows the container (1) to be filled under pressure without pressure.

9 · • · * · * f - β 118630

During the filtration process, the liquid to be cleaned is led into the tank (1) in a malicious manner, whereby the liquid flows through the resin layer (19) through a pipe (3) to the outside of the tank (1).

5 Once the ion exchange resin has lost its effect, it can be regenerated in place as required by the application. During regeneration and washing of the resin bed, it is advantageous to use as little solution as possible and to be able to drain the device between the various stages. However, in this case, the resin bed should not be allowed to dry, which would cause cracking and ducting of the resin bed. To keep the Hart-10 siped always moist, there is an overflow trough (27) in the center tube (9) of each element, which always maintains the liquid surface above the resin bed.

The container (1) can also be emptied through, for example, a valve (26) and opened at the joint (5), after which the elements (4) can be replaced or replaced with a new resin.

The resin (19) has a very small particle size, whereby the resin is packed tightly, causing a high flow resistance. Due to the large filtration area, even large volumes of liquid can be handled even at low flow rates.

The structure according to the invention also occupies a small amount of floor space compared to its capacity.

«T« • t - * • t *

The outer surface area of the compact resin is typically 30 to 40 times that of the corresponding spherical resin. Therefore, it is capable of adsorbing 25 large molecules and colloids that do not fit into the pore of the spherical resin. . or whose pore diffusion into the resin is slow.

* i «• e *

The construction according to the invention allows for large variations in the input flow, since the ··· '** ·' resin layer is protected on the horizontal surface by the fabric (20) and cannot penetrate it. \ 30 even if the flow stops completely.

···· * • -

Example 1 7118630

Lignosulfonates are surfactants and readily adsorb on various surfaces, but they can easily poison catalysts. They also bind basically to anion exchangers, but because they are large spherical molecules (about 50 A in diameter), they do not fit inside conventional ion exchangers.

Laboratory equilibrium tests compared powdered OH-shaped anion exchange resin with conventional ball resin (Amberite IRA410). The powder resin was capable of binding up to 180 mg of lignosulfonate per gram of resin. Correspondingly, the spherical resin bound 7 mg / g resin. At temperatures between 15 and 35 ° C, no effect on capacity was observed, but increasing the temperature 10 slightly accelerated the absorption kinetics. The experiment showed that powdered resin is better suited to bind large molecules like iignosulfonates than spherical resin.

Three different aqueous industrial solutions were filtered with the device according to the invention, in which the fine chemical was to be hydrated. Because the solution also contained small, varying amounts of lignosulfonate, it had to be removed from the solution prior to hydrogenation, since the catalyst would otherwise be poisoned by the lignosulfonates.

Solutions containing 10, 50 and 100 ppm lignosulfonate were purified by the inventive device using a powdered OH-shaped anion exchange »20 resin and 40 mm ion exchange bed thickness. nozzles were 0.064.1.609 and 2.253 ppm, respectively. A similar experiment was also performed on a ♦ * · * '1 m high ion exchange column using Amberite IRA410 sphere resin.

«No purification efficiency was observed on the ion exchange column.

Example 2

Laboratory experiments investigated the removal of a flotation chemical (dialkyldimethylammonium chloride) from an aqueous solution. The following resins were used as resins having a "· backbone of polystyrene-divinylbenzene copolymer (PS-DVB): 30 PS-DVB cation exchange resin [H +], gel, sulfonated, sphere dmin> 200 µm, crosslinked.

': * Start-up rate of 4% DVD

# * ♦ * t e 118630

PS-DVB cation exchange resin [H +], gel, sulfonated, sphere dmin> 400 μΐη, degree of crosslinking 8% -DVB

PS-DVB Cation Exchange Resin [H +], Gel, Sulfonated, Ground ^ <100 µm, Crosslinking Degree 4% -DVB

5 PS-DVB Cation Exchange Resin [H +], Gel, Sulfonated, Ground ^ <100 µm, Crosslinking Degree 8% -DVB

The adsorption rate of the large amine molecule to the ion exchange resin is very slow and requires several hours of contact time to use the resin adsorption capacity economically. When handling large amounts of solution, such as in flotation processes, such long processing times are not possible. The powdered ion-exchange resin provides rapid resin capacity for economical use and only a contact time of a few tens of minutes. Similarly, shorter resin beds may be used for pre-coat filtration.

15

An aqueous solution containing 4.9 ppm Ar-* · "* ·· * moflote 18 foaming chemicals was filtered with the device of the invention. The filtration rate was varied between 0.42 and 2.28 m / h. The experiment was performed at 10 and 30 mm ion exchange bed thicknesses and • · - *** results are shown in Figure 3.

* ·? · - *. 20 • · '• · -

The resin could be regenerated 90% using an aqueous solution containing 10% CaCl 2 and 50% ethanol.

Example 3; * v 25 In the laboratory tests, 5% by weight of fine lime (d = 2 µm) was mixed with methanol. Under normal circumstances, such colloidal lime does not settle ··, ··· 'at all. Addition of powdered H + -formed polystyrene divinylbenzene pad (PS-8% DVB) strong cation exchanger to a solution having a mean particle size of 75 [mu] m was found to be dependent on the ratio of resin to lime. This experiment demonstrates that the functionalized ion exchange resin also works with electrical charges in organic solutions, and colloidal solutions can be purified with an ion exchange resin opposite to the colloidal particles.

Filtration of an industrial hexane-5-based process solution having a dry solids content of about 5% and a temperature of + 60 ° C was performed on the device according to the invention and purified with the above-mentioned PS-8% DVB cation exchange resin. Most of the dry matter (organic components) is dissolved and the inorganic components are either dissolved or colloidal. The inorganic components (= ash at 600 ° C) account for about 0.3% of the dry matter, most of which was lime. Various amounts of powdered cation exchange resin were mixed in solution and the resin was then separated by filtration. Hexane was evaporated and the solid was ashed at 600 ° C. The ash content of the dry matter after treatment is shown in Figure 4. The masses of the various components of the ash in the dry matter are shown in Figure 5, which indicates that the lime has been almost completely eliminated, but other inorganic compounds have also been removed from this process solution.

In order to determine the functionality of the bed, the same solution was continuously treated with * ·· "7 kg of the above powdered cation exchange resin in the apparatus of the invention having a total filtration area of 0.5 m2. was conducted in a continuous flow of 4 m3 / h for 4 hours. The power was stopped at M ** ·. * for two hours and the unit was stopped, then the flow * · · was restarted. The following results were obtained in the experiment: 25 Time Ash Ash Differential pressure: 40 min 0.06 wt% 2.1 bar * ·. ··· 110 min 0.07 wt% 2.7 bar 170 min 0.06 wt% 2.7 bar * 250 min 0.04 % by weight 2.9 bar This example demonstrates that powdered ion exchange resins can remove colloidal or dissolved inorganic components from an organic solvent.

10 118630

The present invention achieves lower ash contents in dry matter than other purification methods studied, such as crystallization.

It is further important to note that in the solution of the invention, stopping the current 5 does not cause a reduction in the shaking power at restart.

Example 4

The apparatus of the example was used to remove the dye from the alcohol. The dyes 10 were mainly antsocyanic compounds derived from grapes. The experiments were performed with both a compact powder resin obtained by grinding a commercial spherical XAD-4 polymer adsorbent (manufactured by Rohm and Haas Co.) and a pre-compact (10 µm) Polyspher PST10 spherical polymer adsorbent (manufactured by Merck KgaA.). Each polymer is a macroporous non-functionalized divinylbenzene crosslinked polystyrene.

Each adsorbent was used as a bed about 30 mm high. The effectiveness of the color removal • t * * ·· * \ was monitored by measuring the visible light absorption of the treated alcohol • · · * · [spectrophotometer. With the adsorbent of both examples, aal * · · *** · was achieved. At 420 and 510 nm, absorbance values less than 1% of the stock solution. . its worth.

• · * • · »• · t * · i ·»

It will be apparent to one skilled in the art that the invention is not limited to the example described above, but may vary within the scope of the appended claims. The advantages disclosed in the embodiment 25 are achieved with a small polymer resin having an average particle size of less than 200 µm, preferably less than 100 µm. The resin may be non-functionalized or functionalized. In the latter case, the resin may ·· -. · *! be in any ionic form. Thus, for example, the type and method of preparation of the ion exchange resin are not limited in any way. The resin bed may contain; 30 also contains more than one type of ion exchange resin mixed, layered or otherwise. The resin may also include inert components, for example fibers, for adjusting the porosity of the resin bed or for improving its mechanical properties.

According to the method, the discriminant effect used in the solution treatment is based on surface adsorption, ion exchange, ion exclusion and / or ion inclusion.

There may also be additional filtration in connection with the drain tube for the ruptured resin particles.

10 The above describes the placement of a resin between two fabrics or membranes, the top of which is secured by pin-fastened rings. Both or only one of said fabrics or films may have a mechanical filter effect.

The resin layer may also be a pre-packed plate-like disc, which is placed in the 15 filtering elements. Such a disc may consist, for example, of fabrics, porous sheets, etc. on both sides of the resin, which are fastened at the edges, for example, to plastic rings. It is also possible to fasten the fabrics to the edges, for example by polyurethane molding. In addition, the disc may include necessary seals that prevent flow past the element.

• · •. 20

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• · · • «

In the example above, the filtering elements are for maintenance and installation; 1.T; for ease, but the filtering elements can of course also be · ·: 1 1 fixed relative to one another.

Also, the method is not limited to the above examples, but is also applicable to the separation of other large molecules and constituents, such as: proteins, polymers, and in the form of colloidal or gels a-C! the.

• · * ♦ 1 »·· * ··« 1 ♦ »* ♦ ···· - • · · 1 · 2 • ·

Claims (16)

118630 A method for treating solutions, in particular with apparatus based on the use of an ion exchange resin, characterized in that the solution to be treated is introduced into a container (1) and treated by passing through a 10-100 mm thick powder ion exchange resin on a horizontally mounted one or more plate cleaning element (4). o outside the container (1). Method according to Claim 1, characterized in that the solution is introduced into a pressure-resistant container (1) in which the horizontal cleaning elements (4) are arranged one above the other in a series (7) for treating the solution through thin compact ion exchange or adsorbent layers (19). Method according to claim 1 or 2, characterized in that in order to prevent cracking and ducting of the resin bed, the ion exchange resin layers (19) are kept moist at all times by means of, for example, an overflow chute • ♦ (27) or the like. The method according to claims 1-3, characterized in that the pressure is **. the pressure used in the vessel (1) is in the range of 0 to 30 bar and a layer of ion exchange resin, either wholly or partially, is formed on the upper surface of the filtration element (4) used to purify the solution; having a particle size in the range of 1 to 300: pm, typically 10 to 300, where the average particle size is preferably 9 9 * 9; ***. less than 200 µm, most preferably less than 100 µm. • · · 30 • · 9 9 9 13 1 1 8630 Process according to claims 1-4, characterized in that the separating effect used in the treatment of the solution is based on surface adsorption, ion exchange, ion exclusion and / or ion inclusion. Apparatus for treating solutions, in particular as an apparatus based on the use of an ion exchange resin, characterized in that a horizontal one or more plate-like cleaning elements (4) are disposed on the container (1) with an approximately 10-100 mm thick powder ion exchange resin layer. Apparatus according to claim 6, characterized in that the pressure-resistant container (1) is provided with horizontal filtration elements (4) used for cleaning, which are arranged one above the other (7) for treating the solution. Apparatus according to Claim 6 or 7, characterized in that the elements (4) are stacked on top of each other in a series (7) starting from the support tube (6) and a guide plate (8) is finally placed on the series (7). . Θ. Apparatus according to claims 6 to 8, characterized in that the central tube (9) of the element · · · 20 (4) consists of an inner tube (10) and an outer tube (11) such that a continuous series (7) is formed with the tube (10) inside the pipe (11) of the preceding element (4). • · • · • · · · · · *. ***. Apparatus according to Claims 6 to 9, characterized in that the element • ® · 25 (4) consists of a base plate (12) fixed to the center tube (9) having a vertical wall (13) and a grating on the plate (12). (14) and fabric (15). • · • * · • · · * · * φ. * ··. Apparatus according to claims 6 to 10, characterized in that the grating «· ..I ,. 30 (14), the inner edge (17) and the outer edge (18) are impermeable to liquid. Apparatus according to claims 6 to 11, characterized in that an ion exchange resin layer (19) is packed on the fabric (15) of the element (4) on which the fabric and / or plate (20) is mounted, which is secured by rings (21) and (22) and locked, for example, by sockets (23). 5 Apparatus according to claims 6-12, characterized in that the inner tube (10) is shorter than the outer tube (11) to provide an opening (16). Apparatus according to claims 6 to 13, characterized in that the fabric 10 (15) is a filter fabric or a nano or microfiltration membrane. Apparatus according to claims 6 to 14, characterized in that, in order to prevent cracking and channeling of the resin capsule, the ion exchange resin layers (19) are kept moist by means of an overflow channel (27) 15 or the like formed in the center tube. Apparatus according to claims 6 to 15, characterized in that the pressure in the pressure vessel (1) of the apparatus is in the range of 0 to 30 bar and on the upper surface of the filter element (4) used for cleaning the solution, * S '***. 20 formed a layer of about 10-100 mm, most preferably 10-40 mm thick. . which is wholly or partly a small ion exchange resin having a particle size range of 1 · 300 µm, typically 10 - 300 µm, with an average of - · · ·. The particle size is preferably less than 200 µm, most preferably less than 100 µm. • ** 999 9 9 9 9 99 9 9 9 9 9 • · · 9 99 9 9 9 9 9 999 9 9 9 9 9 9 9 9 9 ··· 9 999 9 9 9 m * 99 9 9 9 9 9 9 m 15 1 1 8630