DE102021206089A1 - Device for treating water - Google Patents

Abstract

In the device for treating water, at least one supply for water is connected to a rotationally symmetrical cavitation space, which has a concave inner wall and a first volume area, and via which water flows tangentially into the first volume area of the cavitation space. The first volume area merges into a second volume area, which has a convex inner wall. The second volume area is adjoined by a third volume area of the cavitation space, which again has a concave inner wall. The first volume area has a larger inner diameter than the second volume area and the inner diameter of the third volume region is again larger than the inner diameter of the second volume region. A hollow-cylindrical discharge is guided through the entire cavitation space in its central longitudinal axis, which has at least one inlet opening for water in the third volume area and a connection for a discharge line for cleaned water outside the cavitation space.

Description

The invention relates to a device for treating water. Water that is contaminated in the most varied of ways can be treated to such an extent that it reaches drinking water quality.

A wide variety of mechanical and chemical principles are currently used for water treatment, each of which has a wide variety of disadvantages, in particular the cost of substances to be disinfected, the energy required, complex maintenance and the specifications of the TRWV when using substances to be disinfected and operation of drinking water circuits, the disposal of precipitated or filtered substances affect the effectiveness and significantly affect the costs

Among other things, there are already systems in which cavitation is used to treat water.

Cavitation occurs as a result of fast-moving objects in a fluid. According to Bernoulli's law, the higher the speed, the lower the static pressure of a liquid. If the static pressure falls below the evaporating pressure of the liquid, gas or vapor bubbles form. These are then usually entrained with the flowing liquid in areas of higher pressure. When the static pressure rises above the vapor pressure again, the vapor formed suddenly condenses in the cavities and the vapor bubbles or gas bubbles collapse. Extreme pressure (up to approx. 1000 bar) and temperature peaks (up to approx. 5000 °C) occur with a correspondingly large release of energy. Using this energy, it is possible to mechanically damage biological components contained in the water in such a way that they are harmless for subsequent use of the water or can be easily filtered out as suspended matter. By means of the energy generated by the cavitation and the subsequently collapsing steam bubbles and the released oxygen, the formation of radicals (hydroxyl radicals) is stimulated, with which chemical ingredients in the water are also broken down (oxidized) or converted into other harmless or less harmful chemical compounds or chemical elements (disinfected) can be.

Cavitation is essentially initiated as a result of two principles. So once the effect of ultrasonic waves is used. However, it is disadvantageous that a very large amount of energy is required, particularly in the case of large volumes of water.

Another possibility is the use of different flow conditions, which use certain flow speeds of the water and pressure conditions or changes. Here, too, the energy efficiency achieved so far is still too low and there is a need for improvement.

Filters are commonly used in the treatment of exhaust air, but their lifespan is limited and they must be replaced, resulting in downtime and increased costs.

It is therefore the object of the invention to specify options for treating water with which the energy efficiency can be improved and/or the cleaning (oxidation/disinfection) effect can be increased. In the device according to the invention, at least one supply line for, in particular, contaminated water is present in a rotationally symmetrical cavitation space in a first volume region which has a concave inner wall. Clear water can also be used for subsequent treatment of e.g. exhaust air that is to be carried out with the water. Contaminated water flows tangentially into the first volume area of the cavitation space via the at least one feed. The first volume area transitions into a second volume area which has a convex inner wall. The second volume area is adjoined by a third volume area of the cavitation space, which again has a concave inner wall.

A larger inner diameter is maintained in the first volume area than in the second volume area and the inner diameter of the third volume area is again larger than the inner diameter of the second volume area. The contours of the different volume areas can be optimized by calculations taking into account pressure, flow rate and the desired, in particular maximum, volume flow at a higher working pressure than the supply line pressure present. The geometry inside the device with the three volume areas and the dimensions to be adhered to should be selected depending on the specified volume flow.

A hollow-cylindrical discharge is guided through the entire cavitation space in its central longitudinal axis, which has at least one inlet opening for water in the third volume area and a connection for a discharge of treated water outside the cavitation chamber.

In addition, there can be a feed for a gas, which opens into the first volume area in such a way that the gas fed in swirls with the water, is dissolved in the water and as a water-gas mixture through the annular gap via the third volume area into the hollow-cylindrical outlet entry.

The contour of the inner wall in the cavitation space in the three volume areas and the distances of the inner wall from the hollow-cylindrical outlet (3) can advantageously correspond to multiple polynomials of the 3rd and 5th degree (X ₁ , X ₂ , X ₃ , X ₄ ) and the associated coordinate transformation (Y ₁ ) must be trained and complied with.

mit $$r_i\left(x_i\right)=0$$

und diese wiederum für 1 <= i <= 4 jeweils durch ein Polynom 5. Ordnung der Form $$r_i\left(x_i\right)=a_i{x}_i{}^5+b_i{x}_i{}^4+c_i{x}_i{}^3+d_i{x}_i{}^2+e_i{x}_i{}^1+{ƒ}_i$$

definiert sein.A family of contour curves K(z) = K(x _i ) along the inner wall of the cavitation space should be a series of curve sections r _i {x _i ):

With $${\mathrm{right}}_i\left(x_i\right)=0$$

and this in turn for 1 <= i <= 4 in each case by a 5th order polynomial of the form $${\mathrm{right}}_i\left(x_i\right)=a_{\mathrm{<figure-callout\; id="5"\; label="i\; x\; i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0010.png"\; state="\{\{state\}\}">i</figure-callout>}}{x}_i{}_{}{}^5+b_{\mathrm{<figure-callout\; id="4"\; label="i\; x\; i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0011.png"\; state="\{\{state\}\}">i</figure-callout>}}{x}_i{}_{}{}^4+c_{\mathrm{<figure-callout\; id="3"\; label="i\; x\; i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0010.png"\; state="\{\{state\}\}">i</figure-callout>}}{x}_i{}_{}{}^3+{\mathrm{i.e}}_{\mathrm{<figure-callout\; id="2"\; label="i\; x\; i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0010.png"\; state="\{\{state\}\}">i</figure-callout>}}{x}_i{}_{}{}^2+e_{\mathrm{<figure-callout\; id="1"\; label="i\; x\; i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0010.png"\; state="\{\{state\}\}">i</figure-callout>}}{x}_i{}_{}{}^1+{ƒ}_i$$

be defined.

A radially circumferential annular gap is advantageously present between the inner wall of the cavitation chamber and the outer wall of the hollow-cylindrical discharge in the second volume region. The flow rate there should only be increased and the pressure should only be reduced so that no cavitation occurs, with a water pressure of at least 3000 Pa preferably being maintained.

With the annular gap, the flow rate and the pressure of the water in this area and the adjoining third volume area for the cavitation can be advantageously influenced, taking into account the Bernoulli equation. The gap width of the annular gap should be dimensioned in such a way that no cavitation can occur in this area, but the flow of water flowing through the annular gap is strongly swirled. The width of an annular gap should be dimensioned in such a way that the pressure at this point preferably does not fall below 0.1 bar (10,000 Pa) or preferably falls below 1 bar (100,000 Pa), most preferably not below 0.30 bar (30,000 Pa) falls or very particularly preferably falls below 0.5 bar (50,000 Pa).

The at least one supply for water should be aligned at an angle in the range of 100° to 140°, preferably at an angle of 120°, perpendicularly in relation to the central longitudinal axis of the cavitation space, in order to allow a favorable tangential inflow of the possibly still contaminated water, which an advantageous flow of the water within the cavitation chamber along the inner wall through the three volume areas up to the at least one entry opening into the hollow-cylindrical discharge.

In a particularly advantageous manner, a Laval nozzle can be formed or arranged in the interior of the hollow-cylindrical discharge. The Laval nozzle has a particularly advantageous effect if the water to be treated is additionally supplied with a gas from the outside which, in addition to the amount of gases already naturally dissolved in the water, can be cavitated by means of the Laval nozzle.

The Laval nozzle can be arranged with its area in which the smallest inner diameter is present in the first volume area immediately following the second volume area in order to have favorable flow conditions for the water, which is advantageously enriched with gas, with a laminar flow shortly after it flows into the hollow-cylindrical discharge to allow. Flow rates and pressure conditions favorable for cavitation can then be achieved in the hollow-cylindrical discharge by means of the Laval nozzle.

A minimum internal diameter of the Laval nozzle should be maintained so that a pressure of at least 2300 Pa is maintained in the area of the Laval nozzle.

A supply for a gas can advantageously open into the first volume area in such a way that the supplied gas is mixed with the water there, subsequently dissolved in the second volume area and then homogenized in the third volume area before it enters the hollow-cylindrical discharge. With the air that is already dissolved in the water and, if necessary, with the supplied gas, mechanical effects of force are achieved as a result of cavitation, which are used to treat the water. The mechanical effect increases with a higher proportion of gas in relation to the proportion of water. The feed for a gas should likewise open into the first volume region at an angle of between 100° and 140°, preferably 120°.

Air, oxygen or CO ₂ gas can be introduced as the gas.

The hollow-cylindrical discharge can have a constant outer diameter over the entire length within the cavitation chamber.

Several feeds for water and, if necessary, gas should be distributed over the circumference of the cavitation space with the same angular distances in relation to one another, which means that with the same volume flows supplied through the plurality of feeds, there is less turbulent flow of the water along the inner wall of the cavitation chamber into the third volume area is made possible.

The first volume area should have a larger internal volume than the third volume area, with the internal volume in the first volume area preferably being at least three times, particularly preferably at least five times, larger.

The first volume area and the port for the discharge of treated water should be located vertically at the bottom of the device.

For the throughput of different volume flows, for example 0.25 m ³ / h, 0.5 m ³ / h, 2.5 m ³ / h, 5 m ³ / h, 10 m ³ / h or 20 m ³ / h, the inner contour of the cavitation space by means of the given polynomials of the 3rd and 5th order X ₁ , X ₂ , X ₃ , X ₄ and the associated coordinate transformation Y ₁ a fixed feed pressure of the water to be treated in the range 1 MPa to 1.2 MPa, a throughput in m ³ /h and a minimum pressure of 2300 Pa at the narrowest point of the Laval nozzle.

With the device, treated water can be discharged without pressure via the discharge line, if necessary temporarily stored or fed into at least one closed circuit in compressed form and can thus be used again immediately after the treatment has been carried out. When feeding into a closed circuit, a feed pressure that corresponds to the pressure in the closed circuit can be generated with a pump downstream of the discharge line.

The invention makes it possible to treat relatively large volumes of water in a short time, so that the water achieves drinking water quality. It is not just biological components in the water, such as viruses, microbes, bacteria, microorganisms or lower plants (algae) that can be rendered harmless. Particularly when additional gas is supplied, harmful chemical compounds (e.g. arsenic) can also be broken down and converted into harmless or considerably less harmful chemical compounds or chemical elements as a result of the higher mechanical energy that can be achieved and the formation of hydroxyl radicals.

In particular, the proven effectiveness of the process in all temperature ranges enables the specified operating temperatures for drinking water systems to be reduced by more than 20°C in continuous operation. This results in an enormously high energy saving potential (payback period < 2.5 years) as well as the equivalent reduction of CO ₂ emissions in energy production.

The use of heat pumps can be advantageous as they achieve their best efficiency below 50°C. This opens up further energy-saving potential

The oxygen demand (COD) in waste water for the degradation (oxidation) of organic and inorganic substances can be carried out much more efficiently than with conventional aeration processes and technologies.

In addition, hormones and pharmaceutical residues can be completely oxidized or disinfected and the most expensive (in terms of acquisition, installation and maintenance) reverse osmosis technologies can be avoided.

Standing water that grows algae due to the high ambient temperatures or collapses due to a lack of oxygen can be renatured in a short time.

In all livestock farms in which antibiotics are added to the drinking water, the administration of antibiotics and thus medium and long-term resistances or accumulations in the meat of slaughtered animals can be avoided. In addition, the stocking density can be increased in fish farms by permanently increasing the oxygen content in the water.

There are many applications of the invention in agriculture. This also applies in particular to the treatment of exhaust air and, in particular, exhaust air from animal husbandry and biogas production, in order to be able to convert harmful components contained in the exhaust air, such as ammonia, methane, etc., into chemical components that are not or only slightly harmful, in the process according to the invention Device treated water is used for gas scrubbing. The water treated with a device according to the invention should be fed to the respective gas scrubber as soon as possible after exiting the cavitation space in order to be able to utilize the change in properties that can be achieved with the invention, which particularly relates to surface tension and wetting capacity. Intermediate storage, for example in a tank, should be avoided, and the water for the treatment of the respective exhaust air should be used at the latest 0.5 h after passing through a gas scrubbing device according to the invention.

Drinking water can be obtained from any surface water source (lakes, streams, rainwater collection basins) using the device according to the invention at any location, completely independently and independently of other technical installations.

The invention will be explained in more detail below by way of example. Individual features shown in the figures and described for the respective example can also be used independently of the respective representation in a figure or the description of an example.

• 1 eine perspektivische Darstellung eines Beispiels einer erfindungsgemäßen Vorrichtung mit einem Teilschnitt;
• 2 eine Schnittdarstellung durch ein Beispiel einer erfindungsgemäßen Vorrichtung;
• 3 eine perspektivische Schnittdarstellung eines weiteren Beispiels einer erfindungsgemäßen Vorrichtung;
• 4 eine Innenkontur eines Kavitationsraums mit rotationssymmetrischer Konturkurve K(z);
• 5 eine Konturkurve mit zugehörigen Vorgabepunkten P00-P01 und
• 6 eine Konturkurve nach 5 mit einem Bereich um diese Kurve, der erfindungsgemäß berücksichtigt werden kann.

show:

• 1 a perspective view of an example of a device according to the invention with a partial section;
• 2 a sectional view through an example of a device according to the invention;
• 3 a perspective sectional view of a further example of a device according to the invention;
• 4 an inner contour of a cavitation space with a rotationally symmetrical contour curve K(z);
• 5 a contour curve with associated default points P00-P01 and
• 6 a contour curve 5 with an area around this curve that can be taken into account according to the invention.

In 1 an example of a device according to the invention is shown, in which a cavitation space 1 is arranged in a housing 6 . An additional housing 6 can be dispensed with if the cavitation space 1 has been manufactured to be sufficiently stable with corresponding outer walls.

The cavitation space 1 is divided into three volume areas 1.1, 1.2 and 1.3, which each have different maximum inner diameters and inner volumes.

Water to be treated is fed into the first volume region 1.1 via at least one feed 2 with a tangential flow direction perpendicular to the central longitudinal axis of the cavitation space 1.

The first volume area 1.1, like the third volume area, has a concave inner wall. In contrast, the second volume region 1.2, which is arranged between the first and third volume region 1.3, has a convex inner wall. Paragraphs or steps should be avoided on the inner wall, so that the respective transitions on the inner wall of the cavitation space 1 between the three volume areas are formed continuously. This also applies to the changing inside diameters within the entire cavitation space 1 . As a result, the water to be treated can flow along the inner wall in the direction of the third volume area 1.3 and enter several inlet openings 4 there in this example. The inlet openings 4 are arranged on the hollow-cylindrical discharge 3 within the third volume area 1.3. Starting from the third volume region 1.3, the hollow-cylindrical outlet 3 is routed through the entire cavitation space 1 to the outer wall of the housing 6 along the central longitudinal axis of the cavitation space 1 to a connection 5. A line 5.1 (not shown here) can be connected to the connection 5, via which the treated water can be passed on to the consumer or to further treatment, such as filtering.

The inlet openings 4 are arranged at a distance from the inner wall inside the third volume area 1.3.

The hollow-cylindrical outlet 2 has a constant outer diameter over its entire length. In the area in which the second volume area 1.2 has its smallest inner diameter, there is an annular gap which, starting from the first volume area 1.1, tapers conically to the plane in which the second volume area 1.2 has its smallest inner diameter. Starting from this plane with the smallest inner diameter in the direction of the third volume area, the gap width again increases conically.

The clear width of the annular gap should be dimensioned in such a way that no cavitation can occur in this area. However, the flow as vortex should be maintained there. As a result, the water flow is accelerated accordingly and the flow speed increased, whereupon it decreases again somewhat in the third volume area 1.3 before the water flows into the inlet openings 4.

In the example shown, a Laval nozzle 7 is arranged or formed inside the hollow-cylindrical outlet 3, which in turn leads to corresponding changes in flow velocity and pressure according to the continuity and Bernoulli equations with the continuous reduction and subsequent increase in the inner diameter in the hollow cylindrical discharge 3 leads.

The use of the Laval nozzle 7 has a particularly advantageous effect if a gas also flows into the interior of the first volume area 1.1 via a gas inlet 8 on the housing 6 up to an inlet here at the front (similar to water inlet 2), in a flow vortex with the water in the first volume area 1.1 mixed, dissolved in the water in the second volume area 1.2 and supplied as gas dissolved in the water via the third volume area 1.3 of the hollow-cylindrical discharge 3. The dissolved gas flows together with the water through the Laval nozzle 7 and through the hollow-cylindrical outlet 3 until the water treated in this way is discharged, and additional cavitation-related water treatment is achieved with the gas-water mixture.

How one 1 can also be seen, the connection 5 for the discharge of treated water with the device is arranged vertically below and the inlet openings 4 and the inlet 9 for gas vertically above.

Inexpensive air can be supplied as gas. If oxygen or CO ₂ is added, the cavitation-related effect that can be achieved in water treatment can be increased.

with the inside 2 The sectional view shown shows the design of the rotationally symmetrical cavitation space 1 with the hollow-cylindrical discharge 3 arranged therein even better. The first volume region 1.1 has a maximum inner diameter of 180 mm, which is spherical in the direction of the connection 5. In the opposite direction to this, the second volume region 1.2 adjoins, which has an inner wall contour directed convexly inwards. This second volume area 1.2 in turn is followed by the third volume area 1.3, which in turn has a concave inner wall.

Between the outer wall of the hollow-cylindrical outlet 3 and the inner wall of the cavitation space 1 in the second volume area 1.2 with the smallest inner diameter of the second volume area 1.2 there is an annular gap, which in this example has a clear width of 5 mm.

The hollow-cylindrical discharge 3 has an inner diameter that is tailored to the viscosity of the working medium and the pressure conditions, which reduces in the area of the Laval nozzle 7 to an optimized smallest inner diameter of 7.5 mm in this example, before the inner diameter continuously decreases again in the direction of the discharge line 5.1 enlarged.

With a device that has the dimensions listed above, one can, for example, introduce and treat water to be treated with a volume flow of about 2.5 m ³ /h with an inlet pressure in the range of about 10 bar to 12 bar.

Smaller or larger volume flows of water to be treated can be treated in identical devices with the same contours of the three volume areas 1.1, 1.2, 1.3 and the Laval nozzle 7 and the same distance ratios. Devices for the treatment of water can be of different sizes with internal volumes of the three volume ranges 1.1, 1.2 and 1.3 with 0.25 m ³ , 0.5 m ³ , 2.5 m ³ , 5 m ³ , 10 m ³ or 20 m ³ and if necessary, further graduations can be used depending on the project and customer requirements.

With the targeted influencing of the water flow in suitable areas, especially in the direction of flow after the Laval nozzle 7, there is a pressure reduction in the flowing water to be treated, so that cavitation occurs selectively only in the gases dissolved in the water (although a small part of the water is always also cavitated). All assemblies can be calculated or designed in such a way that, with different volume flows, the approximately same pressure conditions and flow speeds, as shown in the example above, can always be maintained.

The representation in 3 shows again in section the basic structure of a cavitation chamber 1 with a hollow-cylindrical discharge 3 arranged therein.

In 4 a rotationally symmetrical inner contour of a cavitation space with contour curve support points P10 - P40 is shown as an example (end points and maxima/minima of the curve progression).

This family of curves is defined in the (global) coordinate space r and z. The z coordinate of point P40 serves as the total length and is equal to 1. The family of curves is therefore normalized to z40.

• Die Punkte P10, P20, P30 und P40 entsprechen den Minima/Maxima des Kurvenverlaufes. Für diese gelten folgende Nebenbedingungen:
  • - r10 < z40 --> Größte Ausdehnung der Kurve in z-Richtung
  • - r10 > r30 > r40 > r20 --> Verjüngung mit steigendem z und schmalste Stelle bei P20
  • - r20 > d/2
  • - d -Außendurchmesser der Zuführung 8 bzw. Durchmesser der Innengeometrie an Stelle z20
  • - Die Punkte P10 bis P40 haben für die Originalkontur folgende Werte:

◯ P10 = (0,268248175 0,291970803) ◯ P20 = (0,770072993 0,063868613) ◯ P30 = (0,954379562 0,169708029) ◯ P40 = (1 0,114963504)

• ◯ Der Punkt P00 liegt auf der Rotationsachse und wird von der Konturkurve aufgrund des Innenteils nicht erreicht

The family of curves should fulfill the following conditions:

• The points P10, P20, P30 and P40 correspond to the minima/maxima of the curve. The following additional conditions apply to these:
  • - r10 < z40 --> Largest extension of the curve in z-direction
  • - r10 > r30 > r40 > r20 --> Taper with increasing z and narrowest point at P20
  • - r20 > d/2
  • - d - outer diameter of the feed 8 or diameter of the inner geometry at point z20
  • - The points P10 to P40 have the following values for the original contour:

◯ P10 = (0.268248175 0.291970803) ◯ P20 = (0.770072993 0.063868613) ◯ P30 = (0.954379562 0.169708029) ◯ P40 = (1 0.114963504)

• ◯ Point P00 is on the axis of rotation and is not reached by the contour curve due to the inner part

• - Kurvenbereich 1
  • ◯ 0 <= x1 <= 1 zwischen 0 <= z <= z10
  • ◯ 0 <= r1 <= 1 zwischen r00 <= r <= r10
• - Kurvenbereich 2
  • ◯ 0 <= x2 <= 1 zwischen 0 <= z <= z20
  • ◯ 0 <= r2 <= 1 zwischen r10 <= r <= r20
• - Kurvenbereich 3
  • ◯ 0 <= x3 <= 1 zwischen 0 <= z <= z30
  • ◯ 0 <= r3 <= 1 zwischen r20 <= r <= r30
• - Kurvenbereich 4
  • ◯ 0 <= x4 <= 1 zwischen 0 <= z <= z40
  • ◯ 0 <= r4 <= 1 zwischen r30 <= r <= r40

To define the family of contour curves, this is introduced mathematically into four partial intervals (valid between the contour curve support points P00-P40) with the following local coordinates:

• - Curve area 1
  • ◯ 0 <= x1 <= 1 between 0 <= z <= z10
  • ◯ 0 <= r1 <= 1 between r00 <= r <= r10
• - curve area 2
  • ◯ 0 <= x2 <= 1 between 0 <= z <= z20
  • ◯ 0 <= r2 <= 1 between r10 <= r <= r20
• - curve area 3
  • ◯ 0 <= x3 <= 1 between 0 <= z <= z30
  • ◯ 0 <= r3 <= 1 between r20 <= r <= r30
• - curve area 4
  • ◯ 0 <= x4 <= 1 between 0 <= z <= z40
  • ◯ 0 <= r4 <= 1 between r30 <= r <= r40

The local variables each run from 0 to 1.

mit
r_i(x_j) = 0 definiert.The family of contour curves K(z) = K(x _i ) is the sequence of curve sections r _i (x _i ): $$K\left(x_i\right)={\displaystyle \sum _{i=1}^4{\mathrm{right}}_i\left(x_i\right)}$$

With
r _i (x _j ) = 0 is defined.

definiert.For 1 <= i <= 4, these in turn are each represented by a 5th order polynomial of the form $${\mathrm{right}}_i\left(x_i\right)=a_i{x}_i{}^5+b_i{x}_{\mathrm{<figure-callout\; id="4"\; label="i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0011.png"\; state="\{\{state\}\}">i</figure-callout>}}{}^4+c_i{x}_{\mathrm{<figure-callout\; id="3"\; label="i"\; filenames="DE102021206089A1\_0009.png,DE102021206089A1\_0010.png"\; state="\{\{state\}\}">i</figure-callout>}}{}^3+{\mathrm{i.e}}_i{x}_i{}^2+e_i{x}_i{}^1+{ƒ}_i$$

Are defined.

The associated coefficients are defined as follows for this curve shape: Table 1 Coefficient matrix of the local curve polynomials, digits in the second line mean further decimal values for the first line.

With the coordinates defined in Table 1, each inner contour of a cavitation space can be determined, which can then be used for a predetermined dimensioning and/or a predetermined volume flow of water in a device according to the invention. Table 1 area i a_i bi c_i d_i egg f_i P00-P10 1 0 0 0.5261780354 12390 -1.70060969 5225190 1.822685284 213210 0.351746375 599588 P10-P20 2 5.184695892 544730 -14.06408543 5880400 10.5740831 94126500 -0.69469365 0790961 0 0 P20-P30 3 -2.455202909 536420 1.76379303444 1850 1.83802265972 5330 -0.1466127 84630830 0 0 P30-P40 4 0 0 0.53196225043 4028 0.4680377495 65972 0 0

This results in the following curve for the original contour, which is shown in 5 is shown.

By choosing any points P01, P02, P03 and P04 that meet the above conditions and within a range of ± 15% from the in 5 are arranged as shown in the reference curve, this results in any curve that is within the in 6 marked area around the reference curve can be determined as an inner contour of a cavitation space 1 that can be used for the device according to the invention.

Claims (16)

Device for treating water, in which a cavitation space of rotationally symmetrical design, which has a concave inner wall and a first volume area (1.1), and at least one feed (2) for water is connected to the first volume area (1.1), via which water is tangentially in flows into the first volume area (1.1) of the cavitation space (1), the first volume area (1.1) transitions into a second volume area (1.2) which has a convex inner wall, the second volume area (1.2) is followed by a third volume area (1.3 ) of the cavitation space (1), which again has a concave inner wall, a larger inner diameter is maintained in the first volume area (1.1) than in the second volume area (1.2) and the inner diameter of the third volume area (1.3) is again larger than the inner diameter of the second Volume area (1.2) is through the entire cavitation space (1) is in its central longitudinal axis a hohlz cylindrical discharge (3) which has in the third volume area (1.3) at least one inlet opening (4) for water and outside of the cavitation space (1) a connection (5) for a discharge line (5.1) of purified water. device after claim 1 , characterized in that the contour of the inner wall in the cavitation space in the three volume areas (1.1, 1.2, 1.3) and the distances between the inner wall and the hollow-cylindrical outlet (3) correspond to multiple polynomials of the 3rd and 5th degree (X ₁ , X ₂ , X ₃ , X ₄ ) and the associated coordinate transformation (Y ₁ ) are formed and maintained. Device according to one of the preceding claims, characterized in that a family of contour curves K(z) = K(x _i ) along the inner wall of the cavitation space as a series of curve segments r _i (x _i ):

With $${\mathrm{right}}_i\left(x_i\right)=0$$

and this in turn for 1 <= i <= 4 in each case by a 5th order polynomial of the form $${\mathrm{right}}_i\left(x_i\right)=a_i{x}_i{}^5+b_i{x}_i{}^4+c_i{x}_i{}^3+{\mathrm{i.e}}_i{x}_i{}^2+e_i{x}_i{}^1+{ƒ}_i$$

is defined. device after claim 1 , characterized in that there is a radially circumferential annular gap between the inner wall of the cavitation chamber (1) and the outer wall of the hollow-cylindrical outlet (3) in the second volume area (1.2), which is dimensioned in such a way that the flow rate increases there and the pressure is only reduced in such a way that no cavitation occurs, with a water pressure of at least 3000 Pa preferably being maintained. Device according to one of the preceding claims, characterized in that the at least one feed (2) for water is aligned at an angle in the range 100° to 140°, preferably at an angle of 120° perpendicular to the central longitudinal axis of the cavitation space (1). . Device according to one of the preceding claims, characterized in that a Laval nozzle (7) is formed or arranged in the interior of the hollow-cylindrical outlet (3). Device according to the preceding claim, characterized in that the Laval nozzle (7) with its area in which the smallest inner diameter is present is arranged in the first volume area (1.1) immediately following the second volume area (1.2). Device according to one of the preceding claims, characterized in that a feed (8) for a gas (preferably ambient air, oxygen and CO2) opens into the first volume region (1.1) in such a way that the gas fed in swirls with the water and is dissolved in the water and enters the hollow-cylindrical outlet (3) as a water-gas mixture through the annular gap via the third volume region (1.3). Device according to one of the preceding claims, characterized in that air, oxygen, CO ₂ or an inert gas can be supplied as the gas. Device according to one of the preceding claims, characterized in that the hollow-cylindrical outlet (3) has a constant outer diameter. Device according to one of the preceding claims, characterized in that a plurality of feeds (2) are arranged at equal angular distances in relation to one another over the circumference of the cavitation space (1). Device according to one of the preceding claims, characterized in that the first volume area (1.1) has an internal volume which is at least three times larger than that of the third volume area (1.3). Device according to one of the preceding claims, characterized in that the first volume area (1.1) and the connection (5) for the discharge pipe (5.1) of treated water are arranged vertically at the bottom of the device. Device according to one of the preceding claims, characterized in that a minimum inner diameter of the Laval nozzle (7) is maintained, that a pressure of at least 2300 Pa is maintained in the region of the Laval nozzle (7). Device according to one of the preceding claims, characterized in that for the throughput of different volume flows, the inner contour of the cavitation space by means of the specified polynomials of the 3rd and 5th order (X ₁ , X ₂ , X ₃ , X ₄ ) and the associated coordinate transformation ( Y ₁ ), a fixed feed pressure of the water to be treated in the range 1 MPa to 1.2 MPa, a throughput in m ³ /h and a minimum pressure of 2300 Pa at the narrowest point of the Laval nozzle (7). Device according to one of the preceding claims, characterized in that treated water can be discharged without pressure via the discharge line (5.1) or can be fed under pressure into at least one closed circuit, the feed pressure being generated by a pump connected downstream of the discharge line (5.1) and the pressure in the corresponds to a closed circuit.

Images