METHOD AND DEVICE FOR ULTRASONIC TREATMENT OF SUBSTANCES

FIELD OF THE INVENTION

The present invention relates to a method and device for ultrasonic treatment of substances. The present invention is advantageously applied in the treatment of material in liquid or semi-liquid form, in particular liquid or semi-liquid substances used in the pharmaceutical or foodstuff field and the like, to which specification expressly refers without thereby restricting the scope of the invention, in order to obtain a sterilization and/or a depyrogenation of the substances, with a significant reduction of pathogenic bacteria present in the same substances, or to obtain an emulsion of one or more internal liquid phases immiscible each other, or a suspension in which one or more solid internal phases are dispersed in one or more external liquid phases.

PRIOR ART

Basically, several different methods of treatment are known for sterilizating and depyrogenating a liquid or semi-liquid material, one of most famous and effective of which includes subjecting the material to a ultrasonic energy treatment or process. According to such a known methodology, in the substance to be treated, for example contained in a tank container or equivalent, it's immersed a sonotrode connected to a generator of mechanical vibrations, in particular, amplified ultrasonic vibrations, which is adapted to generate on the liquid a "bubble-type" energetic effect, universally known as the sonic cavitation, which can lead and contribute to a reduction of pathogenic bacteria on the substance.

In order to creating a continuous ultrasonic energy treatment of the substance, thus eliminating the use of the cited container that must be filled each time and then emptied, it is known, for example by the methodology described and protected in U.S. Patent 6,505,648, the use of a substantially hollow tubular sonotrode, with a variable sectional, within and through which the liquid to be treated is fed continuously to cause a sonic cavitation.

Both the cited methodologies implemented through the use of containers, and, respectively, of the hollow sonotrode for a continuous treatment of the liquid, cause however a considerable inconvenience.

Infact, frequently it occurs that on the treated liquid substance there are waste metal particles inevitably detached from the peripheral surfaces of the sonotrode, which is constantly in direct contact with the liquid.

This drawback becomes, as easily understood, as a very significant problem with extremely harmful consequences, especially for treatment of substances to be used in the pharmaceutical or food field. Moreover, the methodologies as described above are not able to create an evenly spread cavitation in the liquid, since to peaks of sonic vibrations in the immediate vicinity of sonotrode correspond weak energetic effects away from the sonotrode.

SCOPE OF THE INVENTION The scope of the present invention is to overcome the problems and disadvantages of the known methods abovementioned.

Especially, an aim of the present invention is to provide a method and device for the ultrasonic treatment of substances through which it is completely eliminated the possibility that on the treated substances there are sprayed waste metal particles or the like.

Another scope of the invention is to provide method and device for the ultrasonic treatment of liquid or semi-liquid substances in order to realize sterilization and depyrogenation of the substances, or to obtain emulsions and suspensions. Another further scope of the invention is to realize a method and device for the ultrasonic treatment of substances capable of spreading on a substance ultrasonic energy triggering the effects of cavitation spread uniformly.

SUMMARY OF THE INVENTION

According to the present invention is realized a device for ultrasonic treatment of substances, characterized in that it comprises closed conveyor means adapted to continuously feed said substances and ultrasonic generator means arranged in

contact with said conveyor means for generating and spreading ultrasonic mechanical vibrations on said substances through said closed conveyor means. According to the present invention is also provided a method for ultrasonic treatment of substances, characterized in that it comprises the steps of continuously feeding said substances along and within closed conveyor means, and activating ultrasonic generator means for providing ultrasonic mechanical vibrations to said substances through said conveyor means and triggering the ultrasonic cavitation of said substances. The technical characteristics of the invention, in accordance with the cited scopes and aims, are clearly seen from the content of the claims below, and the advantages thereof will be more evident in the detailed description which follows, made with reference to the attached drawings, which represent two preferred forms of realization purely illustrative and not limitative of the device for ultrasonic treatment of the present invention.

BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS

- Figure 1 is a schematic plan view, partially sectional, of a first preferred embodiment of the device for ultrasonic treatment;

- Figure 2 shows a perspective schematic view of the device according to a second preferred embodiment, with parts removed for clarity;

- Figure 3 is a schematic lateral view on enlarged scale of the device shown on figure 2, partially sectional and with parts removed for clarity.

DETAILED DESCRIPTION OF THE INVENTION With particular reference to the attached Figure 1 , with the reference number 1 is generally and schematically illustrated a device for ultrasonic treatment of a substances L, especially pharmaceutical substances (ex. Injectable liquids) or food substances (ex. Milk).

The device 1 comprises a sonotrode 2 connected to a ultrasonic mechanical vibrations generator G which is connected to a piezoelectric transducer 3 adapted to amplify the vibrations.

The sonotrode 2 comprises a inner cavity 5 substantially cylindrical tubular which defines a channel 12.

The device 1 further comprises a hollow tubular conduct 4 mounted on the channel 12 of sonotrode 2 and adapted to define a conveyor, within which the substance L to be treated is continuously fed (arrows K).

Preferably, but not limited, tubular conduct 4 is realized with glass or equivalent material and presents certain dimensions and constant sectional. According to figure 1 , sonotrode 2 is provided with cited annular inner part 5, concentric arranged to the conduct 4, with a cylindrical surface 6 placed in contact with a respective external cylindrical surface 7 of the conduct 4.

Within said annular closed inner part 5 and therefore within the channel 12, water A or other similar liquid is fed, through inlet/outlet holes not shown; water A, in use, is adapted to guarantee the correct and uniform transmission of the ultrasonic energy made by sonotrode 2 to substance L continuously fed along and within the conduct 4 (see arrow K) in order to induce the triggering of the ultrasonic cavitation of the cited substance L.

According to a different solution not shown, conduct 4 is provided with a serpentine type-like structure with a preferred dimension: in such a way it's possible to increase the duration of the ultrasonic treatment of the substance L, without thereby modifying the dimension of the device 1 in-suit.

According to Figures 2 and 3, a second preferred embodiment of the device for ultrasonic treatment is shown and generally indicated with reference 101 : it's to be noted that hereinafter same structural elements of the device 1 and the device 101 are cited with the same reference numbers. The device 101 comprises at least a couple C of identical sonotrodes 102 and 102', each connected to respective ultrasonic mechanical vibrations generator G, G' which is connected to a piezoelectric transducer 3,3' adapted to amplify the vibrations. According to a different solution not shown, such sonotrodes 102 and 102' are connected to a unique generator G with a unique piezoelectric transducer 3 adapted to amplify the vibrations.

Each sonotrode 102,102' is provided with operational end 10,10' for transmission said ultrasonic vibrations, each end 10,10' having flat shaped P, P' with a central semi-cylindrical cavity 1 1 ,1 1 ' with certain diameter.

In accordance with figure 3, in use the sonotrodes 102 and 102' are adapted to be placed with their ends 10 and 10' opposed one against the other at certain distance D so that said cavities 1 1 and 1 1 ' are adapted to form a hollow tubular channel 12 opened in two parts indicated as z1 and z2.

Into the channel 12 is adapted to be mounted, supported by fixing means not shown and placed over the sonotrodes 102 and 102', an hollow tubular conduct 4; said an hollow tubular conduct 4 is adapted to form a conveyor within which the substance L to be treated is continuously fed.

Preferably, but not limited, tubular conduct 4 is realized with glass or equivalent material and presents prefixed dimensions and constant sectional. Within a annular closed inner part 5 formed between channel 12 and conduct 4, through one of said opened part z1 ,z2, water A or other similar liquid is fed, through inlet/outlet holes not shown; said water A is adapted to guarantee the correct and uniform transmission of the ultrasonic energy made by sonotrodes 102,102' to said substance L continuously fed along the conduct 4 in order to induce the triggering of the ultrasonic cavitation of the cited substance L. According to a further variant not shown, the device 101 comprises more than a couple of sonotrodes, i.e. two couples of sonotrodes radially arranged in way that channel 12, into which conduct 4 is closed, is formed by more cavities 1 1 separated each other by opened part z. In operation, the method realized by device 1 ,101 as described, comprises the steps of continuously feeding substance L along and within conveyor means formed by conduct 4 (Figures 1 -3), and at the same time activating said generator means G, G' for providing ultrasonic vibrations to said substance L through said conduct 4 so that to induce the triggering of the ultrasonic cavitation of the substance L and then realizing an optimal and effective sterilization, depyrogenation and homogenization of substance L, in other words obtaining a significant reduction of pathogenic bacteria present in the same substance L, even with high density, completely avoiding the possibility that on the treated substance

there are sprayed waste particles or the like, especially metal particles as instead it frequently happens using known devices.

Moreover, it's to be highlight that with the device 1 ,101 and method as above described it's possible to realize an optimal treatment of a combination or mixture of liquid substances immiscible each other in order to produce a simple emulsion, (that is an internal phase into an external phase), or a multiple emulsion (that is one or more internal phases into an external phase) or a micro-emulsion (that is an emulsion in which internal phase is dispersed with colloidal dimensions between 10 and 70 nm). With the present invention as described, it's possible also to realize a dispersion of one or more internal solid phases onto one or more external liquid phases in order to obtain a suspension.

Advantageously, it's possible to continuously feed along said conduct 4 substances L as liquid, semi-liquid or the like, also mixed with one or more surfactants added to substance L prior to the ultrasonic treatment, so that to promote the stability of the cited emulsions and suspensions. It is finally to be noted that any changes and any variants are possible, all falling under protection according to the solution as described above and claimed below.