RU2550203C2 - Combined universal static mixer-activator - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to static mixer-activator for multiphase systems and can be used for affecting the structure of system of a separate fluid. It comprises four serial sections. First said section swirls the system. Second section subjects it to cavitation. Third section separates fluids in small intersecting jets. Fourth section levels fluid flow rates. Combined, said section mix and varies the structure owing to disturbance of initial intermolecular interaction.

EFFECT: higher homogeneity of liquid-phase system.

8 cl, 3 dwg

Description

The invention relates to a static mixer-activator, designed for multiphase systems as both a mixer and an activator by mechanical action on the structure of these systems or an activator of a single-phase liquid medium. The mixer-activator contains four sequentially installed sections of different operating principles. In the first section, two types of mechanical action are carried out - quasi-shock and vortex; in the second - double cavitation action; in the third section, the fluid flow is divided into small intersecting jets, which create a high level of turbulence. The first section can be called a vortex, the second - of double cavitation action, the third - turbulizer. In the fourth section, the turbulent regime is transferred to the laminar flow regime. Together, these mixers perform both the active mixing function and the structuring function due to the violation of the initial intermolecular interaction. The last section is intended for the final stage of self-organization of the structure of the processed medium associated with a change in the concentration of its components or the emergence of new components.

The technical result consists in increasing the degree of homogeneity of the liquid-phase medium, as well as in changing the concentration of its components and changing the composition.

The invention relates to static mixing devices containing several sequentially arranged mixers of a different mode of action and to the mixing field of multiphase systems, including those being a dispersion medium and a dispersed phase, as well as to the field of directional activation and change of properties of both these systems and a single liquid Wednesday.

The goal is to increase the efficiency of mixing and structuring, as a result of which molecules and molecular chains acquire such a structure that provides a directed change in the properties and composition of the initial processed medium.

This goal is achieved by the consistent application of several static mixers of various designs and operating principles located in one direct-flow apparatus through which the medium to be processed passes under pressure. This design allows you to get a universal static mixer-activator.

As a rule, achieving this goal by means of one type of static mixer requires refinement of its design and technological parameters as applied to specific miscible or activated liquid-phase systems, which is often a long and laborious process.

Therefore, the consistent use of several static mixers of various designs located in one direct-flow housing allows you to get a universal static mixer-activator.

There are several common types of static mixers. These primarily include faucets with screw elements, which are made of a flat thin plate by twisting in the left or right directions (for example: US patents No. 3286992 and No. 3443927; UK patent No. 1413825; ed. Certificate of the USSR No. 504549 and No. 804464) . Screw elements may be located on the surface of a tube, shaft, or shaft (for example, US Pat. Nos. 4,049,241 and 3,797,300).

Other widespread are static mixers with intermediate chambers. Mixing in them is carried out by creating a sharp expansion and narrowing of the space inside the cylindrical body, causing a change in the flow rate and the appearance of enhanced vortex formation associated with separation of the flow from the walls (for example, US patents No. 3404869 and No. 352391; ed. Certificate Czechoslovakia No. 214380; Auth. Certificate of the USSR No. 103903).

Simple in design, but no less effective is a static mixer, in which the intermediate chambers are separated by disks with several through channels (US patent No. 3582048).

Static mixers are also widely used, in which elements from mutually perpendicular plates oriented along a cylindrical body and constituting a spatial lattice ensure the separation of liquids into separate jets and their movement through complex channels where they are repeatedly crushed (for example, US patent No. 3620106).

In addition to direct use, some types of mixers can be used to activate liquids and solutions. As a rule, a magnet or an electromagnet that creates a magnetic field is embedded in the design of such an activator mixer (for example, RF patents: No. 2085277; No. 2275956; No. 2224586; No. 2225223). There are activators with magnetic elements that simultaneously carry out magneto-mechanical processing of a single liquid medium.

In addition to these mixers, mixers with teardrop-shaped elements, with turbulent inserts (injection and ejection) have gained distribution.

The rare principles of the mixers include:

- acoustic resonance (for example, USSR patent No. 909430 and No. 775514);

- a laser beam (for example, RF patent No. 173210);

- cavitation (for example, RF patent No. 2202406);

- transmission of electric current (for example, USSR patent No. 1780822, RF No. 2205681, RF No. 2094106);

- mixing using a venturi (for example, RF patent No. 2093257);

- mixing using a porous insert (for example, RF patent No. 2132724).

The desire to increase the efficiency of small-sized mixers due to the complexity of their designs led to the appearance of many varieties of mixing elements. But such a solution to this problem requires a high-precision and complex manufacturing technology of these elements and especially minimize the existing gaps. Examples are Russian patents No. 2323377, No. 2261755, No. 2080164, No. 2322521.

The technical task of the invention is to use a mechanical effect on liquid-phase systems to obtain a high degree of homogeneity when mixing a dispersion medium and a dispersed phase, and for a separately processed liquid medium, activation and recombination, leading to the breaking of intermolecular bonds due to van der Waals forces, and P-bonds.

To solve this technical problem, it is necessary to carry out a mechanical action with a high specific energy intensity and create a highly developed interfacial surface.

With regard to static mixers, a solution can be obtained by passing flows of mixed liquid-phase systems or a single liquid medium through the movement of elementary volumes, accompanied by the distribution of colliding molecules in relative energies.

A similar approach is contained in patent RU 2411074 C1, adopted as a prototype. The mixing is carried out in an apparatus with successively arranged sections, in the first of which a kinematic action is carried out, leading to quasi-shock, the second mixer is capable of cavitation, the third mixer is capable of dividing the total liquid flow into small intersecting jets.

The main disadvantages of this solution are:

- lack of vortex generators in the first section;

- the use of a single-stage cavitation effect;

- the use in the turbulizer of petal elements, bent in flat plates, which, although it simplifies the design of the turbolizer, reduces its effectiveness;

- the absence of a section in which the laminar flow stretches the molecular chains, orders the arrangement of long and short molecular chains and free radicals, and thereby facilitates the transition from a chaotic state to self-formation of shorter molecular chains.

These disadvantages are eliminated in the proposed combined universal static mixer-activator.

The principles of mixing and activation, incorporated in the proposed mixer-activator, are as follows.

In the first section, the total incoming stream is divided into two or more jets intersecting at a certain angle with a throughput that is equal to or slightly greater throughput of the pipeline supplying the medium to be treated. At the intersection of these jets vortex generators are made in the form of blind holes of a certain diameter and depth.

In other embodiments, the blind hole of the vortex generator is made in any part of one or each jet on its center line or with a shift of the center of the specified blind hole by an amount slightly smaller than the radius of this hole. In the latter case, the column of liquid in the vortex generator is twisted, the collision of the jets initiates the mixing process, which at high speeds acquires a quasi-shock action. The formation of vortices splits the liquid medium into droplets.

In the second section, the cavitation process is carried out due to the fact that the liquid medium is forced through the channels made in the disk parallel to its axis and then enters the chamber, the volume of which provides a pressure drop. From this chamber, the liquid medium passes through channels made in another disk at certain angles to its axis in such a way that the jets leaving these channels enter another chamber, where turbulization and cavitation occur simultaneously.

In the third section of the labyrinth type, the mini-jets are crushed into droplets whose size is less than 5 microns, and at the same time, when these droplets merge, the molecular structure self-organizes. The labyrinth type of mixer is realized in the form of a spatial petal lattice with double bending of the petals.

The fourth section is intended for the final self-organization of the structure in the form of short molecular chains by the addition of free radicals. For this, turbulence translates into a laminar flow with an increase in wall friction.

In the future, the liquid-phase medium will be called the processed medium.

The scheme of the combined universal static mixer-activator is presented in figure 1.

In the direct-flow housing 1 having an inner cylindrical stepped surface, these sections are located: first, second, third and fourth. The ends of the housing 1 are hermetically sealed by the end caps 2 and 3. One of these covers can be made integral with the housing 1. If the housing 1 consists of two joined halves, then their ends can be made blind.

From one end of the housing 1, closed by an end cap 2, having an inlet fitting 4 for a pressurized processed medium, an element 5 is installed having a helical cylindrical surface and shown in FIGS. 2a, b, c. On the indicated cylindrical surface, grooves 6 and 7 are made along a helical line, one of which has a right-handed and the other a left-handed direction. The width, depth and cross-sectional shape of the grooves 6 and 7 must together provide their throughput corresponding to the throughput of the through hole in the specified inlet fitting 4.

At the intersection of grooves 6 and 7, blind holes 8 are made to a certain depth, providing a pressure drop for the formation of a vortex. The number of grooves like grooves 6 and 7 can be increased in pairs. In this case, the number of their intersections and the number of holes 8 in which vortices are formed will be increased. To create vortices in other parts of the grooves 6 or 7, blind holes 9, 10 are also made, the centers of which will either be located on the axial line of these grooves or offset from the center line by an amount smaller than the radius of the blind holes 9, 10. In the latter case, vortex intensification under the action on the medium being treated of tangential displacements of the moving medium.

At the end of the element 5 facing the second section, an annular groove is made, forming an annular cavity, the outer diameter of which is equal to the outer diameter of the cylindrical part of the element 5, and the inner diameter is slightly smaller than the diameter of the circumference of the inner envelope, the cylindrical channels 12 made in the element 11 located in the second sections. Element 11 is a dual cavitator.

In the second section, double cavitation treatment of the medium occurs. It is carried out in two chambers of the element 11, in which a differential pressure is successively observed. Each camera has a disk 13 with a number of through channels of a certain length and configuration, usually cylindrical of small diameter. Behind the disk 13, there is a cylindrical cavitation chamber, called a “sounding chamber”, behind which is the next cavitation chamber with the same or different geometric parameters. In these chambers, due to the pressure drop, the droplets collapse with the release of significant energy. The disks 13 have one end surface tapered.

In the third section, a mixing element 14 is installed, composed of intersecting petals 15, made in thin-walled plates 16 and bent at some angle from the plane of the plate on both sides. Element 14 forms a spatial system of intersecting slits, performing the separation and reunion of flows at the molecular level with multipoint mass transfer. In this case, the exchange of energy allows for the self-organization process associated with the restoration of the structure of broken molecular chains, as well as their structuring, different from the original structure without changing the thermodynamic energy balance. A characteristic feature of the plates 16 is the presence of two bends of the petals 15 at certain angles, which allows you to create more turbulence, figa, b, c. The width of the petals 15, bent to one side, should be equal to the width of the petals, bent to the other side.

The fourth section is sequentially located behind the third section and is designed to transfer the medium to be processed from the turbulent mode to the laminar mode, in which the process of self-organization at the molecular level, which consists in changing the phase state or composition of the substance upon transition to the equilibrium state, is easier. A special case of self-organization is the recombination, association of free radicals, or the addition of sorbed atoms on the surface, including the wall. Since molecular chains are more straightened in the laminar flow, more favorable conditions for recombination are created. As a result of this, the fourth section contains an outlet fitting 19, the inner channel 17 of which has a diameter providing a predetermined flow area corresponding to the flow rate. In the channel 17 along its axis there is a rod 18 in the form of a needle, facing with a pointed end against the flow of the medium being treated, which, in addition to stabilizing the flow, increases wall friction and evens out the velocity diagram.

The mixer activator operates as follows. The pump, which is not shown in Fig. 1, the medium to be processed, both in the form of mixed multiphase systems and activated, as well as an activated single-phase medium, are supplied to the input of the first section through an inlet 4, which has a channel whose diameter also provides a given flow rate, which also depends from pump performance. In the first section, the total flow is divided by means of grooves 6 and 7, made along a helical line with right and left directions on the outer surface of the cylindrical element 5. The number of jets so separated is equal to the number of strokes, but not less than two. These grooves 6 and 7 intersect and this creates a collision of jets, which at certain values of the speeds of the flow of jets acquires a quasi-shock character. Getting into the blind holes of the vortex generators, the processed medium acquires a pseudo-boiling state. Vortex generators in the form of blind holes can be made at the intersection of the grooves 6, 7, or on the axial line of the groove, or with a displacement of the axial line of the blind hole relative to the axial line of the groove by an amount slightly smaller than the input diameter of the blind hole. In the latter case, the medium is twisted by the layers moving in the grooves.

If in the screw-like element 5, an opening 20 is made along the axis, which is closed from the side of the entrance to the first section, then the blind holes 6, 7 are made through, since this causes an additional pressure difference.

In general, in the first section, initial mixing and crushing into relatively large droplets of the treated medium takes place.

Then, the medium to be processed enters the annular cavity and then into the channels of small diameter made in element 13, previously called the first cavitator. In the channels, these droplets undergo great external pressure, and when leaving the channels, due to a sharp pressure drop, these bubbles collapse like a microexplosion with the release of significant energy. From the first chamber of the second section, the medium to be processed enters the channels made in the second cavitator, where it is also compressed, the magnitude of which, as in the first cavitator, depends on the diameter of the channels. It is rational in the second cavitator to carry out channels of different diameters to enhance turbulence. The presence of the first and second cavitators allows one to obtain these bubbles with a diameter of 5 microns and less, and the energy released during cavitation allows one to break long molecular chains into shorter ones, up to the separation of terminal free radicals having a one-way bond. In the first and second sections, both mixing and activation of the processed medium takes place. Then, the mixing process in order to obtain the required homogeneity and further activation takes place in the third section, where the self-organization process associated with a change in the structure of the medium being processed and leading to a change in the properties and composition joins these processes. In order for the self-organization process to proceed more efficiently, the fourth section is used, which has increased wall friction due to the rod element 18 in the form of a needle mounted in the inner channel of the outlet fitting 19, fixed in the fourth section from the end opposite to the pointed one, and the diameters of the inner channel of the outlet fitting and said rod is adopted to provide the required flow rate. The outlet fitting 19 may be integral with the fourth section or separately and fixed to the fourth section, for example, by a threaded connection. In this case, the outlet fitting 19 will be interchangeable depending on the diameter of the hose or pipe connected to it.

Claims (8)

1. Combined universal static mixer-activator of direct-flow type, designed to mix and activate liquid media with a limited energy density supply when passing liquid media through a combined system of fixed elements and is universal for multiphase and single-phase media, consisting of four sections in series, in which the process of mixing or activation is carried out and the transition from the disordered movement of the liquid medium to self-organization in the form of a change in properties and with becoming in accordance with the equilibrium state determined by the energy balance, characterized in that the first section serves to vortex and weaken the intermolecular bonds in this way, the second section serves as a cavitator and initiates the cavitation process with the release of internal energy, the third labyrinth type section serves for mixing and inelastic collision of the jets, accompanied by the process of self-organization of the structure, in the fourth section, the final transition from turbulent states in the laminar and self-organization of the liquid medium due to wall friction. 2. The activator mixer according to claim 1, characterized in that the first section consists of a cylindrical element with grooves of a certain width and depth made on the outer surface, and one groove has an axial line as a screw with a left-hand direction and the other groove has an axial line as screw with right-hand direction and this condition applies to all other grooves in accordance with the number of entries, and at the intersection blind holes are made that serve as vortex generators, and these vortex generators can They are made in other sections of the grooves on the corresponding axial line or with the center of the blind hole offset from the axial line by an amount less than the diameter of the specified hole, and the specified cylindrical element at the end facing the second section has an annular cavity into which these grooves exit, and can have an internal axial hole closed on the inlet side of the liquid medium from the inlet fitting, in which case the previously mentioned blind holes are made through. 3. The activator mixer according to claim 1, characterized in that the second section consists of an element having two stages - the first and second, the first stage adjoins the specified annular cavity of the first section, and each section consists of a disk tightly mounted in the mixer body -activator, and following the first disk of the first annular chamber, in the first disk there are through channels of small diameter connecting the previously indicated cavity of the first section with the first camera, while the total cross-sectional area of the channels in the first disk must ensure the required capacity of the liquid medium, and the first chamber is adjacent to the second disk, also having a number of through channels, the diameters of these channels have a difference in size and location, if these channels do not have these differences, then the second disk is made with a beveled plane from the side of the first camera , also behind the second disk is a second camera adjacent to the third section. 4. The activator mixer according to claim 1, characterized in that the third section includes a three-dimensional spatial lattice assembled from elements in the form of combs made of thin plates and having teeth on one side or two opposite sides, one part of which is bent through one the tooth from the plane of the plate or all the teeth are bent from the plane of the plate through one tooth in different directions, the configuration of the teeth may additionally have one or more bends, as well as a propeller-shaped. 5. The activator mixer according to claim 4, characterized in that during assembly, the flat part of each comb can be located along the center line of the mounting hole, either perpendicularly or obliquely with respect to the specified center line, the configuration of the spatial grid corresponds to the configuration of the mounting hole. 6. The activator mixer according to claim 1, characterized in that the fourth section is located directly in the housing or in the end cap having an outlet fitting, or in the outlet fitting. 7. The mixer-activator according to claim 6, characterized in that the fourth section has a through channel in which a rod is placed, pointed from the end facing the third section and secured by the other end in one of the ways to ensure a given throughput of said through channel . 8. The mixer-activator according to claim 6, characterized in that said rod performs axial elastic displacements under the action of an installed elastic element and pulsations of a liquid medium.

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