RU2818216C1 - Rotary-pulsating apparatus - Google Patents

Abstract

FIELD: various technological processes.

SUBSTANCE: technical solution relates to dispersion and homogenisation means. Device comprises housing with inlet and outlet holes and grinding device installed inside housing with concentric rows of ledges with slots. Device comprises axial source of hydraulic thrust. Device housing is made of polyamide-based polymer material and includes a central section, a rear cover and a front cover, which are connected as a whole by means of detachable joints.

EFFECT: improved quality of dispersion.

4 cl, 5 dwg

Description

Field of technology to which the invention relates

The invention relates to devices for dispersing, homogenizing, moving homogeneous mixtures, in particular, to pumps for processing pulp media of organic materials, and can be used in the food industry, perfumery, in the processing of organic waste, oil and petroleum products, biofuels, bitumen and asphalt coatings , construction materials, obtaining food mixtures, pharmacological preparations and cosmetic mixtures, etc.

State of the art.

A rotary-pulsation apparatus is known from the prior art, containing a drive, a housing with inlet and outlet pipes, and a rotor and stator installed in the housing, on the working surfaces of which there are rows of protrusions located along the circumference, alternating with grooves; the rotor contains an inlet impeller (RU 2516559, published 10 .02.2014). The disadvantage of this known device is the insufficient manufacturability and operation, as well as the high complexity of the seal assembly.

The essence of the invention

The objective of the claimed invention is to improve the operational properties of a rotary-pulsation device that exerts a hydraulic impact on the pulp and expands the scope of application.

The invention achieves the following technical results: increased resistance to clogging, increased pressure characteristics and service life of seals, increased impact on pulp particles, increased processing efficiency.

The specified technical result is achieved by the fact that the rotary pulsation apparatus contains a housing, a grinding device, which contains movable and stationary elements having conical working surfaces, the mentioned movable element contains an axial source of hydraulic traction, the mentioned housing is made of a polyamide-based polymer material and includes a central section , a rear cover and a front cover connected into a single unit by means of detachable connections, a sealing chamber is formed in said rear cover, which communicates with a mixing chamber formed in said central section.

The specified technical result is also achieved by the fact that the grinding device is designed to create centrifugal hydraulic thrust, and the axial source of hydraulic thrust is made in the form of an impeller.

This technical result is also achieved by the fact that the movable element contains a second axial source of hydraulic traction located on the opposite side of the first.

The specified technical result is also achieved by the fact that the movable element of the grinding device is made in the form of a disk assembled from two parts, while the part on which a series of protrusions with grooves and the first axial source of hydraulic traction is formed is made of metal, and the part on which the second is formed axial source of hydraulic traction, made of polyamide-based polymer material.

A distinctive feature of the invention is that the device body is made of polyamide-based polymer material and is assembled, consisting of three parts.

List of drawings

In FIG. Figure 1 shows the top view of the device.

In FIG. Figure 2 shows the device in an axial section.

In FIG. Figure 3 shows the stator of the device.

In FIG. Figure 4 shows the rotor of the device.

In FIG. Figure 5 shows the assembly structure of the device.

Carrying out the invention

The grinding of particles of solid, liquid or jelly-like substances in a liquid medium is required in many industries and in various technologies. Grinding is carried out in the processes of dispersion/dispersion (i.e. crushing particles of a solid or liquid substance in a liquid medium), emulsification (grinding a liquid in a liquid medium). Grinding is a necessary stage of homogenization - the process of uniform distribution of particles of one substance in another.

As a result of grinding and subsequent homogenization, dispersed systems are formed in which one substance is distributed within the volume of another. For example, fat globules in milk, or flour stirred in a glass of water. The distributed substance is called the dispersed phase, and the base of the mixture is called the dispersed medium.

A wide variety of equipment has been created to carry out grinding and homogenization.

The most common disperse systems are emulsions and suspensions. An emulsion is a distribution of small (from 1 to 50 microns) droplets of one liquid in another. A suspension is a suspension of solid particles in a liquid.

The greatest efficiency is achieved by equipment in which the mixed components are simultaneously subjected to a complex of mechanical and physical factors: mechanical shock pulsations, acoustic, resonant and cavitation effects. In such devices, the starting substances and media are crushed (or dispersed) even at the molecular level and, due to turbulence, are transformed into a homogeneous mass.

The present invention relates to flow devices of a rotary-pulsation principle of operation, performing the functions of pumping devices (pumps), activators, mixers, homogenizers and dispersants.

Rotary pulsation devices are successfully used both in food production (fruit and vegetable juices, sauces, purees, soft cottage cheese, yoghurts, mayonnaise, liquor products, beer, casein gels from powdered milk) and in non-food industries (production of medicines and cosmetic substances, processing of petroleum products, biofuels, etc.).

The present invention is a device that is similar in design and operating principle to a centrifugal pump.

The rotary pulsation apparatus 1 according to the present invention is designed to be mounted on a flange of an electric motor 2, as shown in FIG. 1. The device contains a prefabricated housing having 3 inlet and 4 outlet holes.

The body is made of a prefabricated polymer material based on polyamide and includes a central section 5, a back cover 6 and a front cover 7, connected into a single unit by means of detachable connections 8. The inlet 3 for supplying the working medium and mixed components is located in the center of the front cover 7 and is equipped with mounting fittings for the pipeline (not shown). The outlet 4 is located on the side of the central section 5 and is usually directed upward during operation. The outlet 4 for releasing the finished product is also equipped with mounting hardware for the pipeline (not shown).

Polyamide-based thermoplastics are used as the body material, in particular, those produced using the so-called “RIM technology” (“reaction-injection molding”) and have high strength, damping and anti-friction properties, are not subject to chipping and have high resistance to short-term high load with the ability to restore its original shape after removing the load. Such materials have a specific gravity of about 1.18 g/cm ³ and have high chemical resistance to various media (water, synthetic and mineral oils, including with various additives, diesel fuel and gasoline, coolants, alcohols, weak solutions of acids and alkalis). Examples of polymer materials based on polyamides that have the properties listed above include rimamide, anilone, versions of nylon, caprolon, nylon, caproloctane, PA-6, polycaproamide and other materials with similar properties.

A grinding device is installed inside the housing, including a moving element (rotor) 9 and a stationary element (stator) 10, on which rows of protrusions 11 with grooves 12 are made. The rotor 9 is fixed on the shaft of a horizontally located electric motor 2. A key or spline is used to transmit rotation, and for fixing a screw, bolt or nut 19, as shown in Fig. 2.

On the side of the projections 11 and grooves 12, the rotor 9 and the stator 10 have a conical recess made in such a way that in the central part the distance between the rotor 9 and the stator 10 is maximum, and at the periphery is minimal.

The surfaces of the rotor 9 and stator 10, containing protrusions 11 and grooves 12, face each other and form a mechanism that operates on the principle of millstones and with a variable distance between them. In the central part this distance is maximum, and in the periphery it is minimum. After assembling the apparatus, there is a small gap of 0.3 mm to 0.7 mm between the rows of protrusions of the rotor 9 and stator 10 at the periphery. It is most advisable to provide a gap of 0.5 mm, which allows the production of highly dispersed products with particle sizes from 15 microns to 30 microns. In the central part, the gap can reach 5-10 mm. The number of protrusions 11 and grooves 12 of the rotor 9 and stator 10 is determined by the required degree of particle size reduction and homogenization of the final product, as well as by the parameters of the initial mixture. As a rule, 20 to 40 grooves are sufficient.

The grinding device can be configured to create axial hydraulic thrust, which is achieved by the shape of the protrusions 11 and grooves 12, ensuring the injection of a liquid medium under the influence of areas of vacuum in the working environment.

The projections 11 and grooves 12 on the movable element 9 form an axial source of hydraulic traction 13, which provides suction of the working medium through the inlet 3. The axial source 13 of hydraulic traction operates on the principle of an impeller with blades, also known as an impeller or volute. The impeller 13 may be configured as a one-way entry (either clockwise or counterclockwise) as shown in FIG. 4 and double-sided. Making the impeller 13 with a double-sided input will allow you to periodically change the direction of rotation of the motor shaft 2 and change the loaded state of the blades, which will increase their service life.

The rear cover 6 of the housing is designed to be mounted on the flange of the motor 2 and contains a metal sleeve 14 designed to install a mechanical seal 15. The mechanical seal 15 (also known as a “cuff” or “oil seal”) is installed on the shaft of the motor 2 and is held by a sleeve 14 and fixing ring 17. The material of the mechanical seal 15 is selected depending on the components of the dispersed system. To prevent the working environment from entering engine 2, ring 17 acts as a bumper. Mechanical shaft seal 15 is selected depending on operating conditions. The main problem in maintaining seal performance is its heat resistance, since the temperature of the working environment can exceed 90°C. The metal sleeve 14, due to its high heat capacity, ensures heat removal from the seal 15, thereby extending its service life.

To increase the productivity and suction speed of the working medium, the rotor 9 may contain a second axial source 16 of hydraulic traction, located on the opposite side of the first. It is advisable to make the second axial source 16 of hydraulic traction in the form of an impeller with blades. The number and shape of blades are selected depending on the required power and performance.

Structurally, the rotor 9 of the grinding device is made in the form of an all-metal disk. It is most preferable to use stainless steel with a layer of tungsten carbide applied by plasma spraying. Since the second impeller 16 is installed on the opposite side of the rotor 9, its suction direction should be opposite to the first impeller 13.

The fixed part of the grinding device - the stator 10 - is made directly in the front cover 7 of the housing.

It is advisable to make the metal parts of the device from steel 12Х18Н10Т, 10Х17Н13М2Т or 40X13 with the necessary heat treatment (hardening, etc.).

The tightness of the housing is ensured by installing sealing rings 17, 18 between the central part 5 and covers 6 and 7.

The assembled housing contains a mixing chamber and a mechanical seal chamber. In the mixing chamber formed by the inner surface of the central section 5 and the front cover 7, a rotor 9 is installed, the rows of protrusions 11 of which form a variable gap with the rows of protrusions 11 of the stator 10.

Inside the assembled housing, the inlet 3 communicates with the outlet 4 through the mixing chamber and the first impeller 13. The seal chamber is formed by the inner surface of the rear cover 6 and communicates through the second impeller 16 with the mixing chamber.

The mixing chamber has a drain hole 20.

The device works as follows.

The rotary pulsation apparatus is installed on the shaft of the electric motor 2 and secured to its flange, for example, with bolts and nuts. As a result, the mechanical seal 15 is installed on the motor shaft in a metal sleeve 14 and fixed by a ring 17. The rotor 9 is secured to the motor shaft 2, for example, using a nut 19. In the assembled state, the rows of protrusions 11 of the rotor 9 form a variable working gap with the rows of protrusions 11 stator 10. The motor shaft 2 with rotor 9 is driven into rotation.

The principle of operation of the device is that the working medium enters through the pipeline through the inlet 3 into the central part of the rotor 9 and ends up between the abrasive surfaces of the rotor 9 and stator 10. Hydraulic traction is provided by the profile of the protrusions 11 of the rotor and stator, which throw the working medium to the periphery of the rotor 9. The working medium passes in the gaps between the protrusions 11 of the rotor and stator, under the influence of which gradual abrasion and crushing of solid, liquid and gel-like particles of the dispersed phase occurs. The resulting fine emulsion or suspension leaves the unit through outlet 4.

The second impeller 16, located on the other side of the rotor 9, creates additional hydraulic thrust, increasing the performance of the device and increasing the intensity of turbulence in the working environment.

The working medium passes into the seal chamber 15, cooling it due to heat removal. Additional heat removal is provided by a metal sleeve 14, in which a mechanical seal 15 is installed.

The device has not only a mechanical effect on the working environment, crushing the dispersed phase due to impact, abrasion and shearing loads that occur during the contact of particles with the rotor 9 and stator 10.

A high degree of turbulence and flow velocity of the working medium, as well as pressure pulsation, cause the occurrence of hydrodynamic effects. Turbulence occurs in the gap between the rows of protrusions 11. The output flow consists of jets of the working medium passing between the slots of the protrusions 11. It is characterized by complex velocity fields. The presence of a constant source of energy, which is the flow itself, together with turbulence, forms a self-oscillating system. In addition to this, the movement of the protrusions 11 of the rotor 9 relative to the stator 10, causing a jerky change in the sources of pressure and vacuum, leads to the formation of vortices that destroy particles.

The third type of impact that the device has on the dispersed phase is hydroacoustic. It occurs due to intense cavitation and significant shock waves.

The jets of the working medium that have passed the grinding stage are mixed in the mixing chamber, thereby homogenizing the final product.

The rotating rotor 9 ensures the transportation of the finished product into the external pipeline through the outlet 4.

Thus, when the rotor 9 rotates, there is frequent overlap of the protrusions 11 with the grooves 12 of the rotor 9 and the protrusions 11 and grooves 12 of the stator 10. As a result, the pre-mixed components, due to the effects on them of complex pulsating mechanical influences and acoustic, resonant and cavitation phenomena, are subjected to crushing (dispersing) even at the molecular level and due to turbulence they turn into a homogeneous mass. The rotor protrusions 11 impart kinetic energy to this mass and remove it through the outlet 4.

Claims (4)

1. A rotary pulsation apparatus containing a housing with inlet and outlet openings and a grinding device installed inside the housing, which contains movable and stationary elements having conical working surfaces, said movable element contains an axial source of hydraulic traction, said housing is made of a polymer material based on polyamide and includes a central section, a rear cover and a front cover, connected into a single unit by means of detachable connections, a sealing chamber is formed in the said rear cover, which communicates with a mixing chamber formed in the said central section. 2. The apparatus according to claim 1, characterized in that the grinding device is designed to create centrifugal hydraulic thrust, and the axial source of hydraulic thrust is made in the form of an impeller. 3. The apparatus according to claim 1, characterized in that the movable element contains a second axial source of hydraulic traction, located on the opposite side of the first. 4. The apparatus according to claim 1, characterized in that the movable element of the grinding device is made in the form of a disk assembled from two parts, while the part on which a series of protrusions with grooves and the first axial source of hydraulic traction is formed is made of metal, and the part, on which the second axial source of hydraulic traction is formed, is made of a polyamide-based polymer material.