HK1185032B - Method for ultrasonic cavitation treatment of liquid media - Google Patents

Abstract

The invention relates to the field of cavitation treatment of liquid media. An acoustic cavitation mode is formed simultaneously at two or more different frequencies, wherein a mechanical oscillation system - a channel of right-angled cross section - is in the form of consecutively arranged membranes with different fundamental oscillation harmonic frequencies, and sonic oscillations are generated in-phase on opposite sides of the channel so as to form a standing wave, said oscillations, in turn, forming quasi-plane standing waves, which correspond to the membrane oscillation frequencies, in a gap between the channel walls. The width of the gap in the channel is selected by a multiple of a quarter of the wavelength which is excited in the given liquid medium being treated for the frequencies used. The amplitude of the oscillations of the channel wall is selected to be optimum for the various treatment stages of the liquid medium. The method makes it possible to increase the efficiency of cavitation action on the liquid medium being treated and on objects situated in the medium while simultaneously limiting the power of ultrasonic emitters.

Description

Liquid medium ultrasonic cavitation treatment method

Technical Field

The invention relates to the field of liquid media and media or other liquids (65-70% over the total mass) having a density equal to that of water.

Background

It is well known that ultrasonic cavitation can be enhanced by the following process flow/1-6/, in various economic fields:

-glue liquefaction;

-homogenizing and emulsifying;

-mixing;

-splitting;

depolymerization of

In practice, ultrasonic cavitation involves the production of multi-component media (emulsions, suspensions, aqueous solutions and water systems) and ultrasonic sterilization (preservation) of water, milk and other liquid products.

The liquid medium treatment process carried out in the ultrasonic reactor can be regarded as prototype/1/. The method includes generating ultrasonic waves in a liquid through a rod reactor having an acoustic wave source, typically a piezoelectric radiator, adjacent to the rod reactor.

Various forms of rod reactors are available and the abutment end can be fitted with a plurality of piezoelectric radiators, but they all focus on brightening vibrations of the bottom abutment end and the side plate/8/upper rod.

This is because the supercavitation zone is measured in particle size from a few centimeters from the vibrating surface in practice. Thus, the abutting ends of the rods are considered to be the most effective areas since the treatment liquid forms a combined wave between the flat abutting ends and the flat bottom of the radiators. It is therefore noted that it is difficult to make the abutting end larger than 50-70mm in diameter.

The radiation effect of the rod cylinder is much smaller than the amplitude and cylinder divergence. Taking into account the sound waves reflected by the outer wall of the column, an analogy is made with the threat-free field between the end adjacent to the radiating means and the bottom of the column to estimate the optimal conditions for practically treating a planar coherent ultrasonic standing wave in a liquid medium, which is not possible.

The multipath transmission mode, waveless coherence and energy concentration on single frequency of the transmitted and reflected ultrasonic waves in the medium make it practically impossible to obtain an emulsion with a dispersed phase particle size of less than-1.0 mkm and a uniformity standard of no more than 20%. Therefore, the volume of the treatment liquid is limited.

Another alternative method of ultrasonic cavitation treatment of liquid media is to oscillate the rotor.

Through rotor pulsation homogenizer/2/realization.

The liquid is made to produce periodical alternate motion by rotating the stator-rotor of the system, and the sound wave acts on the cavitation effect of the bearing ultrasonic wave in the camera. This is a temporary choice between acoustic cavitation and hydrodynamic cavitation. At present, such homogenizers are most popular, simple in design and capable of handling large volumes of liquid at lower cost than ultrasound simulation devices. The high-speed homogenizer meeting the requirements can obtain the emulsion with the dispersed phase grain diameter of-1.5 mkm and the uniformity standard specification of not more than 12-15 percent in the main mold. However, this approach also presents a number of important limitations, the inability to work with viscous media and handle static liquids (volumetric stator-rotor), and other significant limitations, due to the lower efficiency factor (up to 10%) of the electromechanical system, which limits the ultrasonic energy to 1.5-2 watts/cm.

The closest equivalent method is to prepare a cosmetic emulsion formulation according to the patent application No. 2010137176, 8/2010 and the active decisions of the intellectual property patent and trademark office, 3/2011, 22/ritos.

The increase in the amplitude of the sound waves in the treatment liquid medium is achieved by the superposition of resonant in-phase vibrations on the larger sides of the channel system of rectangular cross section and the waves in the channel, so that the measured distance is equal to the smaller side of the channel and is a multiple of one quarter of the wavelength of the sound waves in the treatment medium. The maximum energy at the resonance frequency on the larger side of the tank can be concentrated and a high intensity acoustic standing wave can be obtained in the tank.

DERMANIKA shows that the main dispersion mode during processing can be 500 nm or less, that the emulsion practically does not include a dispersed phase with a particle size of 1000 nm (1 micron), and that the proportion of emulsifier in the emulsion is two or three times less than usual. Thus, the rotor pulse homogenizer can obtain an emulsion having a dispersed phase size of greater than 1000 nanometers (1 micron) and an emulsifier ratio/2/more.

The XIV international research and practice conference called 2009 "cosmetic formulations and raw materials: safety and efficacy "incomplete report on this study, honor the second name and obtain the certificate, and related publication was also made in the professional journal.

Therefore, the quality of the product improves the maximum efficiency operation resonance mode according to the cavitation standard (cavitation threshold value) [3,4], the most key figure for enhancing the comprehensive processes of physical chemistry, hydromechanics, heat exchange and mass exchange, and the minimum grain diameter and the homogeneity of the oil phase extracted from the produced product.

This technology is implemented on a commercial scale by the cosmetics manufacturer "the laboratory EMANSI of the open shares company (the shares company with only a few stakeholders"). The initial product produced according to this process was a smoke-protective hand cream (suitable for smokers, protecting the skin on the hands from nicotine and smoke), which passed all certification tests.

77.01.12.915, II, 006156.02.10, protocol for health and medical examinations, and statement of compliance approved by independent laboratory tests "Spectroscopy" in 2009, 12.22, 19, Specification (accreditation book number: ROSS RU.0001.21PSH50).

The application of this technique has many limitations (e.g. acoustic waves if used to treat a product placed in a liquid medium). In practice, to achieve higher intensities, the gap width between the walls of the grooves should be no more than half a wavelength. If the medium is water, it corresponds to a size of-3.4 cm and a frequency of 22 khz. In addition, it has been observed many times that the cavitation effect is enhanced if the liquid is treated with two different frequencies. Page 60 of entry/7 shows that during simultaneous impact with ultrasound at two different frequencies (22-44 khz), a significant increase in cavitation is seen, much stronger than that obtained by impacting the sum of the swaths at different half frame rates for each field.

In the test, the experimenter also obtained the actual results and the main correlations of the two frequency effects to obtain different emulsions (cosmetic emulsions, mayonnaise, ketchup, etc.).

Disclosure of Invention

The invention aims to effectively improve the influence of cavitation effect on a treated liquid medium (the energy, the amplitude and the correlation of sound waves) and limit the energy of an ultrasonic source.

This object is achieved by the following method: two or more different frequencies are used to form acoustic cavitation conditions, and simultaneously a mechanical vibration system, a groove with a rectangular cross section, is made into the shape of a series diaphragm, the diaphragm has vibration fundamental waves with different frequencies, and vibrates oppositely to the groove in phase to form standing waves, and in turn, pseudo-planar standing waves corresponding to the membrane vibration frequency in the gap of the groove boundary are formed. Here, the slot gap h can be divided by a quarter wavelength, exiting in the treatment liquid medium at the frequency of use:

h=(k/4)*(C/f i),k=1,2,3,…

wherein:

fi-frequency of standing wave fundamental wave of the channel film, unit: hz;

c-speed of sound in liquid medium, unit: mps;

h-slot gap, unit: m;

the amplitude of the trough edge is adjusted to be optimal for the different treatment stages of the liquid medium and to exceed the acoustic cavitation threshold.

The method uses the concept of simultaneous liquid treatment with different frequencies.

It can be assumed that/3, 7 and others, high frequency cavitation produces bubbles in the liquid, further increasing the acoustic effect at low frequencies at the single cavitation bubble level.

This is achieved by the maximum number of bubbles and the energy of each bubble.

The membrane described is unable to withstand bending stiffness above its vibration frequency compared to a plate. The membrane, in contrast to the plate, does not have its vibration frequency dependent on its standard specification. The particular mode of operation of the membrane-plate depends on a number of factors, such as the conditions of the fixing at the edge (tension), bending, impact frequency, etc./11/.

For an edge-fixed rectangular membrane, the natural vibration frequencies are set to the following solutions/9 and 10/, for back wave propagation in a fixed Cartesian coordinate system:

c-the velocity of the board wave, among others;

K_xand K_y-wave number, the value of which is determined by the boundary conditions;

L_x-the side plates are long, axial Ox;

L_x-side plate length, axial Oy;

j_xand j_y-an integer equal to the number of antinodes in the longitudinal direction of the corresponding side of the plate.

To obtain the peak rebound of the membrane, the vibration mode needs to be the first mode when the number of antinodes is 1 in both coordinate directions. In this case, all points of the film vibrate at the same frequency and phase, being furthest from the center of the film.

Drawings

FIG. 1 is a graph of the resonance characteristics typical of a vibration system-a channel of rectangular, alternating membrane shape in cross section;

FIG. 2 is a line connecting the sizes of the dispersed phases of the cosmetic emulsion;

FIG. 3 is a graph showing a comparison of particle size distribution of a dispersed phase of a cosmetic emulsion.

Detailed Description

Figure 1 shows the typical resonance characteristics of a vibrating system-a channel with rectangular cross section, alternating membrane shape.

It can be seen that the resonant frequency is 23.2khz and the coefficient Q of the vibrating reel system is 7. The amplitude of the acoustic waves in the liquid can be greatly enhanced so that contact with the surface is made possible and the energy delivered to the piezoelectric radiation source does not exceed-50 watts.

The second film was converted to a frequency of-40 khz with a Q factor of-6. The energy delivered to the piezoelectric source is no more than 50 watts (i.e., 2-2.5, as small as possible) than when processed at one frequency.

FIG. 2 is a line connecting the dispersed phase sizes of cosmetic emulsions, wherein the sizes are obtained by using two film slots, and switching to frequencies of 23khz and 40 khz. The high intensity acoustic effect reduces the particle size of the dispersed phase master mode from 600-700 nm (especially for a slot converted to one frequency) to 500 nm, increasing the level of homogeneity to 30-35% in discrete intervals of 100 nm.

FIG. 3 is a graph comparing the particle size distribution of the dispersed phase of a cosmetic emulsion obtained by different homogenization methods-typical homogenizer using a rotor, ultrasonic cavitation at tank 1 frequency (prototype), ultrasonic cavitation at 2 frequency (method used).

The implementation of this method at the DERMANIKA company production site greatly improved the efficiency of the cavitation effect to obtain a high quality cosmetic emulsion, and the treatment volume of the liquid was increased by 2-2.5 times, so that the power of the ultrasonic generator could be reduced from 6 kilowatts to 3 kilowatts.

Reference to the literature

A method for analyzing cavitation and cracking of solids and gelation of gels in high intensity ultrasound fields. The authors' brief treatise on engineering, MISIS, 1967.

Chervyakov V.M and Odno lko V.G. "use of hydrodynamic and cavitation effects in rotor devices": izd-vo Mashini st rienye, 2008.

Experimental studies on ultrasonic cavitation, Sirityuk m.g. In this book, the intense ultrasound field was compiled by l.d. rosenberg, in 1968.

Krassikov v. a sound and ultrasound in air, water and solids-m: fizmatgiz, 1960.

Bergman l. "ultrasound in science and technology and its applications" -m: inost rannayaliterera, 1956.

6.V.I.Demenko, A.A.Getalov, T.V.Puchkova and A.Hotenkova, lack of effective method for emulsifying agent in production process of cosmetic emulsion, journal of raw materials and package, No. 10(101), page 12.

Margulis M, A basic principle of phonochemistry. Chemical reaction of acoustic field "m: vyshaya Shkola, 1984.

Hmelev v.n. and Popova oo v. multifunctional ultrasound devices and their implementation under small-scale production, agricultural, household conditions; scientific monograph, alt. I.I. Polzunov. -Barnaul: izd-vo Al tGTU.

Koshlyakov n.s., Gliner e.b., and Smirnov m. M, Izd-vo Vyshaya shkola, 1970.

Armanovich I.G. and Levin V.I. mathematical physical equations. Second edition, m., Nauka, 1969.

11. Variations of the technology. A manual, 6 parts total, edited by Chalomey v.n., m, and Mashinos trennie, 1979.

Claims (1)

1. A liquid medium ultrasonic cavitation processing method, including the gradual effect of the ultrasonic cavitation, produce the standing wave through the double resonance effect and mechanical vibration system-the cross section is rectangular, trough inside that the membrane forms alternately, characterized by, produce the ultrasonic cavitation mode on two or more different frequencies, thus the mechanical vibration system-the trough with rectangular cross section makes the shape of the serial vibrating diaphragm, the vibrating diaphragm has vibration fundamental wave of different frequency, with the trough in-phase relatively producing the vibration and forming the standing wave, in turn, form the quasi-plane standing wave corresponding to membrane vibration frequency in the interval of the trough boundary, here, the interval h of the trough can be divided by quarter wavelength completely, stimulate the frequency in the liquid medium treated:

h＝(k/4)*(C/f i),k＝1,2,3,…

wherein:

fi-frequency of standing wave fundamental wave of the channel film, unit: hz;

c-speed of sound in liquid medium, unit: mps;

h-slot gap, unit: m;

the amplitude of the trough edge is adjusted to be optimal for the different treatment stages of the liquid medium and to exceed the acoustic cavitation threshold.