DE2623849A1 - METHOD OF ACCUMULATION OF SOLIDS SUSPENDED IN A LIQUID AND EQUIPMENT FOR CARRYING OUT THE METHOD - Google Patents

Description

DipUng. Peter-C. Srofca Dr.-ing. Ernst Stratmann

Patent Attorneys £ 623849

4 Düsseldorf 1 Schadowplatz 9

Düsseldorf, May 25, 1976

LS-12170
7644

Westinghouse Electric Corporation
Pittsburgh / Pa. 15222, V. St. A.

Process for the agglomeration of solids suspended in a liquid and apparatus for carrying out the process

The invention relates to a continuous method of agglomeration of solids of colloidal size or larger size suspended in a liquid and a device for Execution of the procedure.

Various methods are known in which a direct current or a direct current with superimposed alternating current is used is used to aggregate solids suspended in an aqueous liquid. An example of such a thing known process is described in US Pat. No. 3,767,046.

These known methods have many disadvantages which make the respective method impracticable either for economic reasons make or that lead to the fact that the operating costs are very high. For example, processes that involve agglomeration perform by means of direct current, characterized by rapid deterioration of the anode, in particular by Stratification or overgrowth of the anode due to organic materials from the solution or impurities in the metal itself or also from impurities that result from the grain reactions of the anode surface. Therefore, it is a batch

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Telephone (0211) 3208 58 Telegrams Custopat

Operation required because the anode often needs to be shut down and cleaned or replaced during an ongoing Operation or operation for long periods of time is impossible.

Various additional materials are known for the cell, which reduce the tendency of the electrodes to form layers, the current efficiency is increased and the life of the electrode is extended. These additives are effective to varying degrees. However, there is an expense in using it of additives and represent a significant disadvantage when operating with direct current. Obviously, one is continuous Operation or at least substantially uninterrupted operation for an extended period of time without the need Switching off for renewing or cleaning the anode is more economical from an economic point of view than batch operation, even if additives are used.

The applicant of the present method also already has a method for agglomerating suspended solids in one aqueous solution developed, which is characterized in that only alternating current is used in an economical manner is used to ensure uninterrupted operation without the need for frequent replacement or peeling of the anode. It has been found that alternating current is electrostrictive Has an effect on suspended material. In addition, alternating current continuously generates hydrogen peroxide on both electrodes, which helps keep the electrodes clean during operation. After all, the one generated on the electrode possesses Hydrogen has the ability to react with the electrode itself and ultimately produce minimal amounts of metal hydroxides, which act as flocculation nuclei and the flocculation or agglomeration of solid impurities. The electrostrictive effect and the generation of hydrogen peroxide at everyone Electrodes are not possible in a DC cell without the presence of sulfate radicals or other additives. Accordingly, this new method shows a much more effective one

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and above all, uninterrupted operation without the need to use expensive additives.

In the meantime it has also been found that if the solution containing the solids to be agglomerated is between passed through the electrodes on an ongoing basis in the presence of a fluidized bed of conductive particles there will be an extremely much improved agglomeration or flocculation of the solids due to the multitude of electrolytic cells provided in the collapsing field of alternating current will. By using conductive particles that are substantially wear-resistant, is exerted a mechanical abrasion effect on the electrodes, which helps to keep the electrodes in place during the continuous Keeping the plant clean and thus avoiding frequent shutdowns for the purpose of removing shifts. It was also found that by using the method according to the invention the electrode erosion is reduced to about 0.2% of the value that occurs in direct current processes.

The object of the invention is therefore to provide a method for agglomeration of solids suspended in a liquid that need not be interrupted in order to for example to clean the electrodes. In addition, a device for carrying out the method is to be created.

The object is achieved by the features mentioned in the main claim. According to a further embodiment of the invention A turbulently fluidized bed of conductive particles is used, ensuring uninterrupted operation of even higher levels Efficiency is achieved.

It should be noted that the fluidized bed in the invention Cell can only be reached by the water to be processed, but that also the water to be processed can be supplemented by a gas, such as by

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air blown into the vessel. Once a fluidized state has been reached, the likelihood of bridging, Short circuits and the like between the electrodes eliminated. Increased turbulence then increases the efficiency of the invention Process, the upper limit being determined only by the economics of the process.

According to a further embodiment of the invention, the gas-assisted turbulence is increased by the fact that the Side wall of the cell vessel is arranged at an angle to the vertical axis of the vessel. The angled side walls increase the ease with which a truly fluidized bed can be created within the vessel and increase the friction exerted on the surfaces of the electrode by the particles of the bed.

When using an alternating current generated electric field As mentioned above, the conductive particles become bipolar electrodes, so that the cell has a plurality of these Contains electrodes, each electrode creating its own interface. The particle motion input to the fluidized bed not only ensures continuous cleaning of the electrode surfaces, but also of the individual particles and their boundary layers. Hence, maximum turbulence achievable with a given device provides the maximum Efficiency that can be obtained according to the invention.

First, alternating currents with a frequency of 0.2 to 800 Hz were preferably used on the electrodes, the one electric current of a magnitude of about 0.08 to 6 amps per

2 2
6.45 cm (inches) through the bed. It has also been found that it is particularly favorable if the length of stay in the bed is between 9 and 25 s and the distance between the electrodes is between 6 and 50 mm, a distance of approximately 13 mm being particularly favorable. However, if desired, the distance between the electrode surfaces can also be greater than 50 mm. The distance of about 13 mm

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as well as the parallel arrangement of several cells to hold the water to be processed is more favorable.

The object of the invention to provide an improved method for agglomeration of those suspended in an aqueous liquid Creating solids is not only, as already stated, by passing the liquid through an alternating current field achieved while maintaining a turbulent state of the liquid, but also according to a further embodiment nor by the production of hydrogen peroxide at each electrode, A further support of the agglomeration of the suspended matter contained in the aqueous solution is achieved in that these suspended solids are exposed to a fluidized bed, the conductive particles subjected to an alternating current field contains. The effect of a large number of electrodes in a collapsing alternating current field is particularly favorable a turbulent fluidized bed of conductive particles, breaking the floating forces and causing the solids become, clump together, clump together, or flake. The turbulent fluidized bed of conductive particles is preferably located between two spaced apart Electrodes connected to a source of alternating current. By the state of turbulence in the bed and by the the suspended forces are eliminated and suspended solids are formed by the plurality of electrodes formed therein clumped so that they can be by means of conventional Process can be deposited from the liquid.

According to a further advantageous embodiment, the spaced electrodes of the fluidized bed are in arranged a vessel, the side walls of which are at an angle to the vertical axis of the vessel, whereby the turbulence state can be maintained particularly easily and promotes the cleaning effect on the electrode surfaces so that the abrasion of impurities deposited thereon is further improved.

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Further details, advantages and possible applications of the invention emerge from the accompanying illustration of exemplary embodiments as well as from the following description.

It shows:

Fig. 1 is a plan view of a device that is particularly favorable for carrying out the method according to the invention is;

FIG. 2 shows a vertical section through the vessel part of the device of FIG. 1, with the central part removed became;

Figure 3 is a sectional view taken along lines 3-3 of Figure 1;

Figure 4 is a sectional view taken along lines 4-4 of Figure 2;

Figure 5 is a sectional view taken along lines 5-5 of Figure 2;

Figure 6 is a sectional view taken along lines 6-6 of Figure 2;

Figure 7 is a sectional view taken along lines 7-7 of Figure 2;

Figure 8 is a sectional view taken along lines 8-8 of Figure 2;

9 shows a graphic representation of the efficiency of the method according to the invention, measured over the percentage light transmission as a function of the residence time in the inventive Vessel;

10 shows a graph of the current density over the residence time, the current consumed and the flow rate;

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11 is a graph showing the relationship between the amount of water treated and the current density versus the flow rate and the flow rate;

12 is a graph of the cell resistance; when graphite particles are added to the water for both alternating current and direct current;

Fig. 13 is a graph showing the temperature in the cell with the relationship to the cell resistance; namely in the case of a non-fluidized and in the case of a fluidized cell bed; and

Figure 14 is a graph of the linear flow rate Above the bed level to build up fluidization with different particles as bed components.

In Fig. 1, a device is shown with which the invention Process for the treatment of aqueous liquids which contain suspended solid materials, particularly favorable can be carried out. The device includes a vessel 10 which may contain any desired number of cells, for example the two cells shown (see Fig. 3), which will be described in more detail below. Each cell 12 in the vessel 10 is controlled via a console 14. The console 14 is for monitoring and controlling the turbulence in the cell and supplying the desired current and voltage used to electrodes. The console 14 can be connected to a source of electrical energy e.g. B. connected via a cable 16 and deliver the desired voltage and current via cable 18 to the cell electrodes. Of course the console 14 is not an essential feature for the implementation of the invention. Instead, individual Controls are used.

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As mentioned earlier, the turbulence can be created by the water to be processed that is supplied to the cell is, or by additionally added gas, such as air. In the case of a multitude of cells it is it is particularly advantageous to provide a separate inlet for the water and for the air in each cell. Accordingly According to FIG. 1, the water to be processed through a line into the cell inlets 22 and 22 ′ in the lower part of the vessel 10 pumped. The flow of the water to be processed can be monitored by flow meter 24, for example. The gas for supporting the fluidized bed condition within each cell, according to a preferred embodiment Air is pumped to the bottom of each cell through line 26 and via inlets 28 and 28 ' fed. The console 14 can be various measuring and display devices and the like to control and monitor the flow into cell 12. The vessel 10 also includes one Outlet 29 in the upper part of the vessel for the water with the agglomerated solids, which according to the method according to the invention were treated. The water with the solids flowing out of the outlet 29 can by conventional means be fed to any desired separation plant, such as a settling tank, a centrifuge, a scraper, a flood treatment cell ο. like

According to Fig. 3, the vessel 10 comprises in the illustrated embodiment Twin cells 12 containing opposing electrodes. The electrodes 30 are through insulation spacers 32 separated and held by side walls 34 and front walls 36. The inner electrodes are also through insulating spacers 38 separately.

The electrodes in each cell 12 can preferably be made of any ⁿ non-valve "metal, such as aluminum, magnesium, or steel. For most applications, however, aluminum is preferred. The opposing electrodes, as explained above, are spaced

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from 6 to 50 mm to each other, but preferably a distance of 13 mm. Any number of cells 12 can be used in the vessel 10 However, one or two cells, as shown in FIG. 3, or up to ten or are particularly favorable more cells. In any case, however, the electrodes are preferably parallel to one another.

The upwardly extending side walls 34 of the vessel 10 can be vertical, but it is particularly favorable to have these walls to be arranged at an angle to the vertical. This angle is preferably between 5 ° and 30 ° with respect to the vertical, A deviation of 10 is particularly favorable. The angle of the side walls 34 should, as already explained, the formation of a turbulent fluidized bed within each cell 12. The electrodes 30 extend in essentially over the entire central area of the vessel up to close to the angled side walls 34.

In Figs. 2, 4, 5 and 7, an inlet chamber 37 is in the Base 39 of the vessel 10 is provided to hold the water to be processed, which is supplied through the inlets 22 and 22 ', to mix with the air coming through the inlets 28 and 28 ' is introduced into the mixing chamber 42 to create the desired turbulence. A screen 40 lies above the inlet chamber and below the mixing chamber 42. A screen 44 is located above the mixing chamber 42 to, as will be described, the fluidized To hold the bed and to limit it to the central part of the vessel 10 between the inclined side walls 34. The side walls 46 of the lower portion 39 of the vessel 10 may be vertical as shown. If desired, the vessel 10 can also be held on a base 48.

In Figures 2, 6 and 8, the upper portion 50 of the vessel includes an upper delivery chamber 52 which is above the electrodes is arranged. A screen 54 lies above chamber 52 to maintain the fluidized bed within chamber 10. Electrode leads 56 extend from electrodes 30

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and are adapted to be connected to cables 18 which connect the electrode 30 to the console 14 and the source of connects electrical energy transmitted through the cable.

While water to be processed flows up through the sieve 54, a weir 58 separates the interior of the vessel 10 from an outlet plenum 60 in which the processed water is collected to be withdrawn through an outlet 28. That processed water from outlet 28 is then solidified by any conventional means, as previously mentioned Separating station transported, such as a stripping device, a settling tank, a centrifuge or the like. (Not shown). Alternatively, the processed water can also be returned to the vessel 10 through inlet 20, wherein the clumped plague bodies serve as flocculation germs, to get even greater purity.

The side walls 64 and the front and rear walls 36 can be connected to the corresponding side, front and rear walls of the central part of the vessel 10, or they can be welded to it. The side walls can be of any desired configuration suitable for forming the chamber as well as the outlet chamber 60, as will be apparent to one of ordinary skill in the art.

The precise particle size of the constituents of the fluidized bed is not critical and can range from about 3 mm up to 6 mm is enough. Based on investigations carried out, it has been found that to achieve bed stability in a certain desired residence time the ideal particle represents a sphere whose diameter is approximately 3 mm and whose specific weight is approximately 2. That used However, the material can be any conductive material that has excellent mechanical and chemical stability. Preferably the bed particles should be suitable for true fluidization. If the bed is not fluidized, can, as already indicated above, bridge formation

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and short circuits occur, which can reduce current efficiency. In a preferred embodiment of this invention graphite pellets are used which are cylindrical and have a nominal diameter of 3.175 mm and a nominal length of 4.82 mm have, with a specific weight of 2.1. The cylindrical pellets resulted in improved turbulence in the fluidized bed and increased their electrical effects.

Fig. 14 illustrates the results of the experiments based on the Creation of a fluidized bed in a tube, the inner diameter of which was 15.9 mm and with the possible bed components was filled. Each ingredient was mixed with water at the various speeds shown fluidized. Bed height relative to speed is shown in FIG.

A number of tests were also carried out using a cell that had parallel side walls and an electrode plate spacing of 10.2 mm to measure the conductivity of the selected graphite particles relative to temperature to be determined in the fluidized bed, and alternatively in a state in which fluidization is not achieved became. It has been found that e.g. B. at a water flow rate of 6 l / min and an air flow rate of 0.2 SCFI ^ as bed of expanded to a "non-flowing" height of 400 mm to a fully fluidized height of 813 mm. At a current density

2 2

of 0.19 A per 6.45 cm (inches) and a power consumption, which was equivalent to 3.11 kWh per 4000 liters, dramatic flocculation occurred. In the case of a fluidized bed, one clearly occurred lower power consumption compared to the power consumption when there is no bed, as shown in FIG. 13.

Fig. 12 explains the change in cell resistance when Graphite pellets are added to 225 cm of water in order to register the greatly increased conductivity that occurs with alternating current occurs in a fluidized bed compared to co-current.

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FIGS. 9-11 illustrate the results obtained in experiments similar to that shown in FIGS. 1-8 Establishment were carried out. In these tests, the plate spacing between the electrodes was 13 mm and the bed volume was approximately two thirds of the actual volume between the electrodes. In addition were the side walls inclined by 10 ° with respect to the vertical.

In Fig. 9, the efficiency of the invention Device shown, namely over the residence time of the liquid to be processed. The efficiency is in Percent light transmission measured with a spectrometer at a wavelength λ = 5500 £, with distilled Water was used as the 100% standard. Thus, the efficiency, or the percentage of light transmission, a measure of the clarity of the treated water compared to distilled water. It was true in this experiment treated water, the results of which are shown in Figure 9, the white water runoff of a paper mill, however the results are also representative for other fluids treated. As shown, should be the optimal length of stay fall in the linear part of the graph, between approximately 9 and 25 s only a small increase in light transmission compared to the required current. The length of stay will be accordingly in the device according to the invention are preferably between a total of 9 and 25 s.

The device according to the invention has been used to treat various types of waste water. For example was the rinsing liquid treated for coke ovens, then spring water containing colloidal iron, further wastewater containing colloidal graphite from hard paper mills and soda mills, also machine factory oils in water emulsions (drilling fluid), soap waste water, that occurs during copper drawing, household wastewater, paper mill sludge, as well as various other commercial and domestic wastewater streams. In all cases the content of suspended

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substances are significantly reduced within the preferred length of stay specified above.

Specific examples for the use of the method according to the invention are given below. In every example the fluidized bed was formed by graphite pellets, which had a specific gravity of about 2.1.

Example I.

A total flow rate of 14 to 20 l / min with colloidal graphite contaminated water and an air flow rate were used from 1 to 1.5 SCFM in the two-lined vessel of Figs. 1-8 to ensure good fluidization with cylindrical To achieve graphite pellets, as described above, the graphite pellets having a specific weight of about 2.1 owned. A total current of 30 A at a voltage of 50 V AC of 60 Hz was applied to the electrodes and the colloidal suspension "broken". The suspended solids content was 1285 ppm in the untreated Water reduced to 38 ppm after running the water once through the unit followed by approximately two hours Settling time in a holding tank, not shown. The water that ran in had a temperature of 1.11 to 3.33 C. Higher influence temperatures obviously lead to higher conductivity, i. that is, as a general rule, owns water at 21 C a conductivity that is 2 to 3.75 times as high, like water at 0 C, depending on the amount and type of impurities.

Example II

Paper mill lagoon sludge was made in a Machine processed as described in Figs. 1-8. The sludge was originally treated with aluminum sulphate,

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but contained suspended solids which under normal conditions would remain in suspension for years. The mud possessed a very high viscosity and a light transmittance of 0%. The suspended solids were 5.4% by weight and 1.3% of the solids were aluminum hydroxide.

The mud was in the ratio of urban water 3: 1 diluted. The flow rate through the device according to the invention was 12 l / min, with an alternating current of 60 A and 60 V was applied to the electrodes.

The treated sludge contained solids which precipitated within 10 minutes and were the suspension forces completely broken. The surface water light transmittance of the processed sludge after one hour was 86.5% at a light wavelength of 475, u. Measured suspended solids remained in an amount of 11 ppm.

In summary it can be said that it was found that by alternating current flowing over a turbulent fluidized The bed of conductive particles is laid on, effectively and economically the solids suspended in water on continuous Base decreased. The generated turbulence increases the efficiency of the electricity and contributes to an electrostrictive Effect by which a large number of bipolar electrodes are generated within the cell, which break the suspension forces of the solids. The solids then clump together, whereby they can be removed in a simple manner by settling or skimming or the like.

In contrast to the known methods, the use of alternating current means that the electrode surfaces remain for the efficient ongoing operation is relatively clean, mainly due to the generation of hydrogen peroxide as well as due to the mechanical abrasion effect of the bed particles. The hydrogen peroxide also contributes to the discoloration and deodorising the treated water, such as

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will be familiar to the person skilled in the art. Most importantly, the alternating current enables continuous operation, without the need to shut down the system to replace a damaged anode or to clean an anode, nor does the process require expensive additives to operate efficiently.

The improved method and apparatus for the continuous agglomeration of colloidal size solids or larger size, which are suspended in a liquid, so there is - around the idea of the invention again to summarize briefly - in the passage of the liquid through spaced apart electrode plates in the presence of a fluidized bed of conductive particles, the liquid suspension being an electrical Field is exposed through a applied to the electrodes and flowing through the conductive particles of the bed Alternating current comes about. The turbulence of the particles in the bed improves according to the findings of the Applicant reduced the conductivity and the current efficiency the electrode erosion and reduces the soiling and coating through the mechanical friction effect of the bed particles of the electrodes, so that the suspension forces of the said solids are broken quickly and effectively. The agglomerated Solids can then be removed using conventional methods such as skimming, settling, floating and the like. Be separated from the liquid.

The invention can also be embodied in other forms which have not been described herein without departing from the actual Invention idea is deviated. The embodiment described here is intended in every respect only for Explanation and not serve to limit the invention.

Claims ;

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Claims (40)

Patent claims: 1 J Continuous process for the agglomeration of solids suspended in a liquid of colloidal size or larger size, characterized by the arrangement of at least one pair of metal electrodes, the front surfaces of which are essentially closely spaced from one another; Guiding the liquid in a continuous flow between the opposing front surfaces of the spaced electrodes and past these front surfaces; Applying an alternating voltage with a frequency of about 0.2 Hz to 800 Hz to the electrodes; Control of the alternating voltage with relation to the distance between the front surfaces of the electrodes and to the conductivity of the liquid in order to obtain an alternating current flow between the two electrode surfaces, 2 2 its value between 0.08 and 6 A per 6.45 cm (inch) Electrode surface lies; Creation of a fluid-induced movement in the liquid to produce a Turbulence in the liquid with a Reynolds number of at least about 10,000, while the liquid is between the spaced apart front surfaces of the electrodes and flows past them. 2. The method according to claim 1, characterized in that the electrode is made of a metal that is not Represents precious metal and also does not represent valve metal; that to produce the turbulence compressed gas in the Liquid is introduced; that the specified conditions are maintained, so that during the flow the liquid between the metal electrodes forms metal hydroxides on the electrode surfaces, while current flows between the electrodes; and that the flow rate of the liquid stream is so controlled that the liquid between the electrode front surfaces lingers long enough to cause the particles in the colloidal suspension to close 709837 / 0B81 SL aggregate solid particles of a size that at least 5000 Α units, so that such solid particles do not have a colloidal suspension in the liquid represent more. 3. The method according to claim 2, characterized in that the metal of the electrodes is aluminum, an aluminum alloy, Is iron, magnesium or steel. 4. The method according to claim 2, characterized in that the metal hydroxides are caused to adhere to the electrode surfaces without the presence of alkali metal salt additives in the liquid. 5. The method according to claim 2, characterized in that alkali halide salts are present in the liquid, while this liquid is on the surfaces of the spaced apart standing electrodes flows past. 6. The method according to claim 2, characterized in that the metal hydroxides are caused on the electrodes to be formed without an external addition of hydroxides to the liquid occurring between flows through the electrodes. 7. The method according to claim 2, characterized in that the specified conditions are maintained, so that the alternating current that runs between the electrodes generates hydrogen peroxide at the electrodes, whereby metal hydroxides are formed on the electrodes. 8. The method according to claim 2, characterized in that the front surfaces of the electrodes at the start of operation of the procedure have a distance of approximately 13 mm. 7 0 9837/0581 9. The method according to claim 2, characterized in that a pH range of 2 to 9 is maintained while the liquid flows between the electrodes and past the electrodes. 10. The method according to claim 2, characterized in that the liquid between the electrodes and on These flows past, a conductive material is added, which creates and sustains a facilitates current flowing between the electrode surfaces, the current density being within the specified range Area. 11. The method according to claim 10, characterized in that the material added to the liquid at least one is a suitable salt that is soluble in the liquid. 12. The method according to claim 1, characterized in that the current density of the flow between the electrode surfaces 2 the current is maintained in the range of 0.08 to 3 amps per 6.45 cm. 13. The method according to claim 1, characterized in that the alternating current density to a value between 0.08 and 0.5 A. 2
per 6.45 cm. 14. The method according to claim 1, characterized in that the Density of the alternating current is kept at about 0.19 A per 6.45 cm. 15. The method according to claim 1, characterized in that the The density of the alternating current is maintained at approximately 1.0 amps per 6.45 cm. 709837/0561 16. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 1.5 A per 6.45 cm will. 17. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 2.0 A per 6.45 cm. 18. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 2.5 A per 6.45 cm. 19. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 3.0 A per 6.45 cm. 20. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 3.5 A per 6.45 cm. 21. The method according to claim 1, characterized in that the Density of the W < will hold. Density of the alternating current to about 4.0 A per 6.45 cm 22. The method according to claim 1, characterized in that the The density of the alternating current is kept at about 5.0 amps per 6.45 cm. 23. The method according to claim 1, characterized in that the The density of the alternating current is maintained at about 6.0 A per 6.45 cm. 24. The method according to claim 1, characterized in that the frequency of the alternating voltage is between 10 and 400 Hz. 709837 / 0B61 25. The method according to any one of the preceding claims 1 24, characterized in that the flow rate of the liquid is chosen so that it is about 9-25 s between the electrodes. 26. The method according to claim 10, characterized in that the conductive material is graphite. 27. The method according to claim 26, characterized in that the conductive material has a specific weight of about 2 to 2.1. 28. The method according to claim 1, characterized in that a fluidized bed of conductive abrasion-resistant particles between the facing front surfaces is provided and that the liquid to be treated is uninterrupted between and past these front surfaces flowing through the bed. 29. The method according to claim 28, characterized in that the conductive particles have a specific gravity of approximately 2 own. 30. The method according to claim 29, characterized in that the particles consist of graphite. 31. The method according to claim 30, characterized in that the particles are cylindrical in shape. 32. Device for carrying out the method according to the preceding claims 1 - 31, characterized by a vessel (10) with front wall (36), rear wall and side walls (46) and with an inlet (22) for the supply of water to be purified and an outlet (29) for water and aggregated solids, the side walls (46) of the vessel (10) in lie in a plane which is perpendicular to the horizontal axis of the vessel (10); with at least two upright- 709837/0561 standing electrodes (30) which are arranged within the vessel (10) between the inlet (22) and the outlet (29) are, wherein the electrodes have at a distance opposite metal front surfaces, which together with the side walls of the vessel form a water treatment chamber, which with the inlet (22) and the outlet (29) of the vessel (10) is in communication; by means that are connected to the electrodes (30), an alternating current with a frequency of 0.2 to 2,800 Hz and a current density of 0.01 to 6 A per 6.45 cm to feed; by pumping means carried by the device for guiding the water to be purified through the inlet (22) into the vessel and through the treatment chamber, and for the subsequent passage of the treated water through the outlet (29) out of the vessel; by devices carried by the device to move the patient to be treated Water inside the treatment chamber to keep the water in a turbulent state while it is moving located between the electrodes (30); and by conductive means between the electrodes within the chamber are arranged in order to intensify the alternating electric field over the electrodes when the water to be purified is located inside the chamber. 33. Apparatus according to claim 32, characterized in that the side walls (34) are in a plane with respect to the vertical axis of the vessel has an angle of up to 30 °. 34. Apparatus according to claim 33, characterized in that the angle is 5 to 30 °. 35. Apparatus according to claim 34, characterized in that the angle is approximately 10 °. 709837/0581 36. Apparatus according to claim 32, characterized in that the opposite front surfaces of the electrodes (30) lie in planes which are parallel to the vertical axis of the vessel (10). 37. Apparatus according to claim 32, characterized in that the means for moving the water is a source for pressurized gas associated with the chamber is in communication and is designed so that the gas can be introduced into the chamber. 38. Device according to i * .nspruch 37, characterized in that the Gas is air. 39. Apparatus according to claim 32, characterized in that the conductive devices comprise graphite pellets. 40. Apparatus according to claim 33, characterized in that the front surface of the electrodes (30) consists of a metal, which can be aluminum, iron, steel or magnesium. ES / jn 5 709837/0561