Process and apparatus for spray-distribution with ultrasound

The invention relates to a method for introducing Sprühverteilen or disperse a Zumischmediums, in particular a dosing liquid, in a to be treated Main liquid according to the preamble of claim 1 and one to the Performing this method provided apparatus according to the preamble of claim 12.

Such a method and such a device go everywhere to Application, where the introduced into a main liquid to be treated Admix with the main liquid does not mix and therefore in the Main liquid must be very finely divided form.

This is for example in the cold sterilization of beverages is the case, during the introduction a precipitating agent in a liquid, etc.

In such processes, especially in the cold sterilization of beverages, as non-alcoholic flavored drinks, dealcoholized wine, liquid Tea concentrates, etc., is so far proceeded in a manner that a with the Main liquid not mixing, but easily and quickly decaying cold disinfectants, especially dimethyldicarbonate (DMDC) to the main liquid is introduced by a spray nozzle. This admix (DMDC) has for the cold sterilization as advantageous process in the beverage industry preserved and acts even at a dosage 6-20 ml / hl beverage against Yeasts, fungi and bacteria. After its introduction into the main liquid disintegrates DMDC rapidly into carbon dioxide and alcohol, that is in such ingredients, the natural Ingredients of many drinks.

The information to be pressurized spray distribution of such Zumischmediums in Although main liquid spray nozzles has the desired effect of a relatively fine distribution of the Zumischmediums in the main liquid. However, can the uniform distribution of Zumischmediums in the main liquid, the yes to does not mix with the main fluid and therefore are dispersed in this must to be desired. In addition to the spray nozzle enters certain mechanical Wear, so that these replaced after a relatively short time must become.

Finally, also the energy consumption for the supplied under pressure to the spray nozzle Admix high because, for example, a feed pressure of 25 bar must be created and maintained.

The invention is therefore based on the object to eliminate the described to create disadvantages a method and a device by means of which the distributed admix in the main liquid as finely and evenly is, at the same time the wear of distributing low and the energy expenditure should be reduced.

This object is achieved with the method according to the invention by the features of claim 1 and with the apparatus of the invention by the features ACCORDANCE of claim 12 is released. Advantageous embodiments thereof are in the respective subclaims.

In the present process, the procedure is such that the admix, in particular the dosing liquid, when introduced into the main liquid distributed there by means of vibrational energy of high frequency and the smallest Droplets is decomposed with high total surface area.

According to an advantageous embodiment of the inventive method applied ultrasound to generate the oscillation energy of high frequency. Here, the ultrasonic preferably oscillates at a frequency between 20 to 80 kHz.

It is within the scope of the invention that as ultrasonic such for use passes, having an adjustable amplitude.

The ultrasound is expediently generated by a ultrasonic vibrator, either continuously or intermittently.

The dosing liquid may also continuously or intermittently the Main liquid are fed. This can be either by means of a supply line carried out at least at their exit point vibrates in the ultrasonic range, or it is possible to proceed such that the dosing liquid discharges into the main liquid to an oscillating in the ultrasound range face of a High frequency vibration generator is applied.

In any case, by the inventive process, the decisive advantage achieved that the dispensing liquid in the main liquid extremely consistent distributed and very numerous small droplets with high total surface is decomposed, so that a highest possible effectiveness of the main fluid introduced dosing liquid is obtained. At the same time wear is the reaching as distributor for applying the ultrasonic vibrator extremely low, and also the energy required for the operation of such an ultrasonic exciter compared to the use of a spray nozzle is minimal.

The method and apparatus according to the invention can be personalized with special Advantage of producing a homogeneous mixture between a admixable and apply a main fluid, both fluids in addition to the liquid phase, a gas phase and / or a solid phase can. The admixable liquid flows out batchwise or continuously to a surface on which the admixable liquid due to the introduced Sound waves, which preferably move in the ultrasonic range, in which Main liquid atomized and dispersed therein. At said surface, at the Zumischfluid leaves a water discharge outlet, and the surrounding Main liquid prevail changing high pressure differences. This result cause the admixable extremely finely divided, ie is nebulized. This Effect is due to the occurring cavitation. The they exit from admixable For example, the end face of a rod, ie probe like a Ultrasonic generator (sonotrode), which projects into the main liquid. This can be dormant or flow intermittently or continuously.

The outlet cross section of admixable can run open or lockable be. The finely atomized by the sound energy is in admixable the main liquid dispersed. This can also sparingly soluble or schwermischbare fluids are homogeneously distributed in the main liquid. Becomes the fluid to be distributed not continuously conveyed to the outlet cross-section, but intermittently passed through a metering pump there is the nebulized Admixable over internals so passed constructively that an ideal Distribution is achieved in the static or flowing primary liquid. provided it is a flowing primary liquid, is suitable constructional Measures achieved turbulence increase, thereby sufficient for a to provide axial and radial distribution of admixable.

The ultrasonic vibrator used in the invention, which respectively for atomizing Dispersing the admixable liquid passes into the main liquid to the application, is a commercially available ultrasonic processor with frequencies between 20 and 80 kHz and operates at a power 12-1000 W achieves an efficiency of up to 90%.

In such an ultrasonic vibrator, wherein the fine distribution in the present invention a non-soluble liquid into a main liquid using ultrasound takes place, the ultrasonic transducer is provided as coupling oscillators with amplitude transformer educated. As electro-acoustic transducer, a composite transducer reaches the Application. This represents a cylinder, at its end faces in the axial Direction ultrasonic vibrations are emitted. At one of the two circular areas is the fixed Coupled amplitude transformer. This causes that an appropriate form of a reduction of the circular radiating Increasing the amplitude of vibration occurs. It arises at this point a high intensity ultrasonic field.

The admixable or the liquid to be dispersed is the main liquid through a central axial bore inside the probe-shaped ultrasonic vibrator supplied, the admixable liquid on the end face of the probe in the main liquid emerges. The admixable is the axial bore through fed a radial bore extending at a node of the ultrasonic vibrator is.

Facing the front surface of the ultrasound oscillator is formed alternately in the liquid an overpressure phase and a negative pressure phase, depending on whether the Vibrator expands or contracts.

During the phase of contraction, the equivalent to the negative pressure phase is formed in the liquid due to their limited pulling capability innumerable small cavities. These fall into the following expansion phase the vibrator, which is equivalent to the overpressure phase, together, ie implode. This process is known as cavitation.

To the forming cavitation bubbles around caused by the pop-like Implode high local pressures (up to 10,000 bar) and strong turbulence in of the liquid. These phenomena can be viewed as the essential criteria be that the desired fine distribution of the two liquid phases lead in the main liquid.

The invention is explained below with reference to the drawings. Show it:<dl tsize="7"><dt>Fig. 1</dt><dd>schematically in section a for carrying out the invention Process device provided with a probe-shaped Ultrasonic vibrator (horn) in which the supply of the admixable takes place centrally through the probe, and</dd><dt>FIG. 2</dt><dd>a modified embodiment with distributed liquid feed.</dd></dl>

As shown in Fig. 1 of the drawings can be seen to be treated flows through a main liquid 1 - in the illustrated embodiment a to be sterilized by cold sterilization Drink - forms in the direction of arrows 2 3 through a pipeline This at the location shown a pipe elbow, in such a way that the Main liquid 1 is deflected by approximately 90 ° in its direction of flow the second

In the treated main liquid 1 a admix 5 to be introduced are, in the form of a very finely divided spray, the smallest having droplets with high total surface area. This admix 5 is it in the illustrated embodiment, a liquid cold disinfectants in the form of dimethyldicarbonate (DMDC), which in the smallest amounts Current of the main fluid must be 1 homogeneously distributed and thus as dosing liquid to be introduced into the main liquid first

For this purpose, the dosing liquid 5 upon introduction into the main fluid 1 distributed by vibrational energy of high frequency and desired in the smallest droplets decomposed with high total surface area. As vibrational energy high frequency ultrasound enters the application, between a frequency 20 to 80 kHz swings.

This ultrasound is generated using a commercially available ultrasonic vibrator 6, at its front end a mounting flange 7 is fastened. This is in the manner shown in FIG. 1 example, sleeve-shaped or cylindrical with conical to its front end widening inner wall 8 is formed and its front end on the pipe elbow 3 or at the edges of a corresponding opening thereof is welded, namely at such a position, that - in the view of FIG. 1 - the horizontal longitudinal central axis of the ultrasonic vibrator 6 with the horizontal longitudinal central axis of the part leading away the pipe 3 is aligned.

At the front end of the ultrasonic vibrator 6 is provided centrally of the actual probe-shaped trained high-frequency vibration generator in the form of a horn 9 fixed, with his front in the ultrasonic range oscillating face 10 projects into the main liquid stream of the first The horn 9 has a central Axial bore 11 which lies at its at the end face 10 of the sonotrode 9 Exit point in the main liquid 1 opens and at its entry point a radial bore 12 to place in the direction of the arrow 13 of lead Dosing liquid 5 is in the main liquid 1 in conjunction.

Due to the in direction of the arrows 14 oscillating back and forth in the ultrasonic range Sonotrode 9 incl. Their end face 10 is the there escaping dosing 5 atomized to fine droplets and in the main liquid 1 the desired manner uniformly dispersed.

The mounting flange 7 has with its conically widening inner wall 8 a hygienic design and fulfilled, also due to its Other design and arrangement, as the low surface roughness Material, self-cleaning property, ease of access for automatic Cleaning and disinfection, called "Cleaning In Place" (CIP) and "sterilization In Place "(SIP), the special requirements of the food industry.

In the modified embodiment according to FIG. 2, the horn 9 of the Ultrasonic vibrator 6 for supplying the admixed dosing liquid 5 no central axial bore. Instead, the dosing liquid flows 5 the main liquid 1 via a separate supply line 15 to which the on the wall interspersed pipe elbow 3 welded receiving flange 7 inward and so on the vibrating in the ultrasonic range end face 10 of the horn 9 and the ultrasonic vibrator is directed 6 that the amount initiated dosing liquid 5 likewise broken down into tiny droplets with high total surface and distributed in the form of a uniform spray in the main liquid 1 becomes. In contrast to the previously described embodiment, Here thus a decentralized supply of dosing liquid 5 in the Main liquid. 1

With regard to the above has not explained in greater detail in the individual features of the invention expressly for the rest of the drawing and the claims referenced.