RU2788202C1 - Recirculating mixer of combined action - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to a mixing equipment that provides the production of multicomponent mixtures, and can be used in various industries for mixing bulk components and additives. The recirculation mixer contains horizontally mounted chambers connected by loading and unloading pipes with shafts located in them, carrying multidirectional blade devices. In the macro-mixing chamber, those are single-threaded screw blades, and in the micro-mixing chamber, on the loading side, double-threaded screw blades installed in pairs. The mixer is equipped with a homogenization chamber of the mixture of the main components and additives and a mixing chamber of additives interconnected with each other and with macro-mixing and micro-mixing chambers.

EFFECT: use of the invention will make it possible to expand technological capabilities and improve the quality of mixtures.

5 cl, 11 dwg

Description

SUBSTANCE: invention relates to mixing technique providing multi-component mixtures and can be used in various industries: chemical, construction, fuel, housing and communal services, etc. for mixing bulk components and additives.

A mixer design is known (RF patent 2188064 MPK7 B01F 7/02, filed on 10/04/2001, application 2001126981/12, published on 08/27/2002), containing three successively arranged chambers with shafts on which bladed devices of various configurations are fixed, and in the second the chamber is equipped with nozzles for supplying liquid and viscous components.

The disadvantage of the mixer is the complexity of its design, the impossibility of interchangeability of the working bodies, as well as the increased maintainability of the unit.

A mixer for mixing dry ingredients and additives is also known (RF patent 2616641 IPC A23N 17/00, B01F 7/04, B01F 7/08, declared 26.04.2016, application 2016116430, publ. 18.04.2017, BI No. 11), containing a hopper with an unloading auger, the end part of which is made in the form of U-shaped blades of circular cross section; a parallel hopper of additives with a drum feeder, and below them - a chamber for preliminary and main mixing with sequentially installed U-shaped blades of active mixing and a two-way spiral conveyor.

The disadvantage of the mixer is the limited throughput (capacity) of the unit, as well as the large overall dimensions of its individual chambers and the short duration of mixing.

The closest technical solution selected as a prototype is a recirculation mixer (RF patent No. 2302285, IPC B01F 7/02, filed 16.06.2005, application 20051187704/15, publ. 10.07.2007, bull. No. 19), containing located in the vertical plane, two mixing blocks, the upper of which consists of a cylindrical chamber with single-threaded helical blades fixed on the shaft, of different directions of the helical surface, rotated relative to each other at an angle of 170-190 °, and the lower block consists of two smaller chambers located in a horizontal plane diameters connected by nozzles to the upper chamber. In the lower chambers on the shafts there are two-way helical blades of different directions of the helical surface, rotated relative to each other at an angle of 80-95°.

The disadvantage of the prototype are the limited possibilities of implementing various technological processes: for the preparation of polyfractional or polycomponent composite mixtures; polycomponent mixtures of microadditives, microgranular composite mixtures, etc.; poor mixing quality.

The following set of features of the invention coincides with the essential features of the prototype: the presence of horizontally mounted chambers with loading nozzles and shafts located in them with multidirectional paddle devices limited by an intermittent helical surface and various geometric profiles. In this case, in the upper chamber of the first block, single-threaded helical blades are located on the shaft, and in the left lower chamber of the micromixing of the second block, from the side of the central load, two-threaded helical blades are installed in pairs.

The task to be solved by the invention is to expand the technological capabilities and improve the quality of the mixtures, due to the intensification of the recirculation effect of the working bodies at each stage of macro- and micro-mixing of components, steam humidification and micro-granulation of composite mixtures.

The problem is solved due to the fact that the recirculation mixer contains horizontally installed chambers of different diameters, connected by loading and unloading nozzles with shafts located in them, carrying multidirectional bladed devices, limited by an intermittent helical surface of various geometric profiles, and in the macromixing chamber - by single-thread helical blades, and in the micromixing chamber, on the loading side, - with two-way helical blades installed in pairs.

In the proposed solution, the recirculation mixer contains a loading hopper, chambers for macro-mixing, micro-mixing, homogenization of the mixture of main components and additives, and mixing of additives installed under the hopper. The chambers have shafts located in them, bearing bladed devices, limited by an intermittent helical surface of various geometric profiles and interconnected by loading and unloading nozzles.

The macro mixing chamber is connected to the hopper. The helical blades of the chamber are made of single-thread, multidirectional action and are made up of rods rigidly fixed on the shaft, and there are plates on the working surface of the blades. The macromixing chamber is connected by means of its discharge pipe to the loading pipe of the micromixing chamber.

_сф=70-110°. Камера смешивания добавок соединена патрубками с камерой макросмешивания и камерой гомогенизации. В камере добавок со стороны загрузки материалов па валу установлена как минимум одна пара двухзаходных лопастей с рабочими винтовыми поверхностями, направленными навстречу друг другу. За этими лопастями на валу установлена такая же пара лопастей, направление винтовой линии которых совпадает с направлением вращения вала. Загрузка материала в камеру добавок осуществляется из камеры макросмешивания через входной патрубок. Для подачи в данную камеру гетерогенных добавок она снабжена питающими устройствами и дополнительным входным патрубком. Выгрузка гомогенизированной смеси из камеры добавок осуществляется через выходной патрубок, причем между последней парой однонаправленных с валом лопастей па валу установлено интенсифицирующее устройство, выполненное в виде П-образных рамок из стержней круглого сечения. Рамки имеют разную высоту, закреплены консольно на валу параллельно его горизонтальной оси и смещены вокруг оси вала по окружности в сторону, противоположную его вращению. Наибольшими угол смещения крайних П-образных рамок составляет

_П=50-90°.In the micromixing chamber, the helical blades are double-threaded, with multidirectional action and are made up of rods, on the working surface of which there are also plates on top. The mixture obtained in this chamber is unloaded through the discharge pipe into the homogenization chamber for the mixture of main components and additives, which is located on the same vertical axis as the macromixing chamber, connected to the additive mixing chamber. The supply of additives to it is carried out through the supply gates of the chamber body, while coaxially to the body of the homogenization chamber there is an internal chamber with a diameter of d _VK inside it. =(0.4÷0.7)D _K.G. and length L _V.K. =(0.3÷0.5)L _K.G. , where - D _K.G. and L _K.G. inner diameter and length of the homogenization chamber. Inside which, on the loading side, a pair of two-way blades is installed on the shaft, the working surfaces of which are directed towards each other. Behind these blades, a two-way directional blade adjacent to them is installed on the shaft, as well as in the unloading zone from the chamber - an unloading blade with the same direction of the helical surfaces of the previous blade, but displaced along the circumference in the direction of shaft rotation by an angle α=70-90°. Between the directional blade and the unloading blade, there is a device for intensifying the process of mixing and microgranulating the mixture, made in the form of spherical cavities placed in opposite frame contours, formed by arcuate elements. The opening angle in each cavity between the extreme elements in the direction opposite to the rotation of the shaft is

_sf \u003d 70-110 °. The additive mixing chamber is connected by branch pipes to the macro mixing chamber and the homogenization chamber. At least one pair of two-way blades with working helical surfaces directed towards each other is installed on the shaft in the additive chamber on the side of loading materials on the shaft. Behind these blades, the same pair of blades is installed on the shaft, the direction of the helix of which coincides with the direction of rotation of the shaft. The material is loaded into the additive chamber from the macro mixing chamber through the inlet pipe. To feed heterogeneous additives into this chamber, it is equipped with feeders and an additional inlet pipe. The unloading of the homogenized mixture from the additive chamber is carried out through the outlet pipe, and between the last pair of blades unidirectional with the shaft, an intensifying device is installed on the shaft, made in the form of U-shaped frames of round cross-section rods. The frames have different heights, are cantilevered on the shaft parallel to its horizontal axis and are displaced around the axis of the shaft along the circumference in the direction opposite to its rotation. The largest offset angle of the extreme U-shaped frames is

_P \u003d 50-90 °.

In addition, the proposed mixer implements the following additional features.

2. The mixer according to claim 1, characterized in that on the outer working surface of the rods of single-threaded and double-threaded helical blades, plates are fixed with a height, respectively, H _OVL = (0.2 ÷ 0.5) R _OVL and H _OVL = (0.2 ÷0.5)R _DVL , where R _OVL , R _DVL are the radii of the circles described by single-threaded and double-threaded blades, respectively.

3. The mixer according to claim 1, characterized in that the rigid fastening of single-threaded and double-threaded blades on the shafts is provided by detachable bushings - clamps.

4. The mixer according to p. 1., characterized in that in the micromixing chamber and the mixing chamber of additives and the homogenization chamber, the displacement angle γ _vygr. unloading two-way blades relative to intensifying mixing devices, in the direction opposite to the rotation of the shaft, is γ _vygr. =30÷50°.

5. The mixer according to claim 1, characterized in that sealing blinkers are installed in the inlet pipe of the homogenization chamber for the mixture of main components and additives, and in the body of the inner chamber there is a fitting for supplying and discharging the binder in a sprayed or vapor state, while to intensify the mixing process, the inner part of the spherical cavities formed by arcuate elements is provided with a rigidly fixed mesh coating.

The presence in the mixer of 4 horizontally installed chambers of different diameters with paddle devices leads to the expansion of the technological capabilities of the unit. This is achieved in the chambers of the unit as follows.

The installation of single-thread helical blades in the macromixing chamber makes it possible to intensively homogenize the mixture due to the double recycling of the material.

Execution in the micromixing chamber of double helical blades makes it possible to homogenize the mixture in a microvolume due to fourfold recycling of the mixture.

The use of two pairs of two-way helical blades and a frame U-shaped intensifying device in the mixing chamber of additives contributes to the intensification of the process of micromixing of additives.

The presence in the homogenization chamber of a mixture of the main components and additives of a frame device with adjacent spherical blades of increasing radius from rods of round cross section contributes to the final mixing and microgranulation of all components of the composite mixture.

Thus, the expansion of the functionality of the recirculation mixer is provided, incl. for mixing composite mixtures with heterogeneous (heterogeneous) components, for example - fiber fillers: intensification of the process of homogenization of mixtures at each stage of their preparation through the use of helical bladed devices of various geometric profiles. The latter provide an intensive volumetric-spatial recirculation movement of material flows, and, if necessary, microgranulation of the composite mixture, improving the quality of the resulting mixture (compactness; lack of segregation of the mixture components during its transportation; dusting, increased moisture demand, etc.).

The parameters given in the formula and description are optimal in magnitude and were obtained during pilot studies of the design in the laboratory of BSTU. V.G. Shukhov "Resource-Energy-Saving Technologies, Equipment and Complexes" ("RETOK").

The essence of the proposed technological solution is illustrated by graphic material, which presents:

in fig. 1 - general scheme of the mixer;

in fig. 2 - view A, in Fig. 1; the location of single-threaded helical blades along the length of the macro-mixing chamber of the mixer;

in fig. 3 - section A-A, in Fig. 2; layout of single-threaded helical blades according to the angles of rotation in the macromixing chamber, Fig. 2;

in fig. 4 - view B, in Fig. 1; arrangement of two-way helical blades along the length of the micromixing chamber;

in fig. 5 - section B-B, in Fig. four; layout of two-way helical blades at the angles of rotation in the micromixing chamber, Fig. four;

in fig. 6 - view C, in Fig. 1; the location of the combined paddle devices along the length of the chamber for intensive mixing of additives;

in fig. 7 - section C-C, in Fig. 6, diagram of the arrangement of the loading and unloading two-way blades according to the angles of rotation in the chamber for intensive mixing of additives, fig. 6;

in fig. 8 is an axonometric view of the paddle frame device of the chamber for intensive mixing of additives, FIG. 6;

in fig. 9 - view D, in Fig. 1, the location of the paddle devices along the length of the chamber for homogenizing the mixture of main components and the mixture of additives;

in fig. 10 - section D-D, in Fig. 9, diagram of the arrangement of the loading and unloading two-way blades according to the angles of rotation in the chamber for homogenizing the mixture of the main components and the mixture of additives, fig. nine;

in fig. 11 is an axonometric view of an intensifying device with spherical cavities of a homogenization chamber for a mixture of main components and a mixture of additives.

The recirculation mixer contains technological chambers located under the hopper 1 of the main components of the composite mixture (Fig. 1), having individual drives (not shown in Fig.).

The hopper 1 is connected to a horizontally mounted macromixing chamber 2 with a loading pipe 3 and is equipped with discharge pipes 4.5. In chamber 2 (Fig. 2), single-threaded helical blades (SVL) 7 of multidirectional action are installed, made up of rods 8, which are rigidly fixed to the shaft 6 with the help of detachable sleeves- _clamps 9. (0.2÷0.5)R _OVL , where R _OVL is the radius of the circle described by the blades 7 (Fig. 3). The opening angle of the intermittent helical surface OVL 7 is β=160÷200°. The angle of rotation of multidirectional surfaces OVL 7 is γ=180°. In the unloading part of the chamber 2, the discharge pipe 4 (Fig. 2, Fig. 3) is connected to the loading pipe 11 of the micromixing chamber 12.

In the chamber 12 on the horizontal shaft 13, with the help of bushings-clamps 9, two-way helical blades 14 (DVL) of multidirectional action are evenly fixed, in the direction from loading to unloading the mixture (Fig. 4). The latter are made up of rods 15, on the working surfaces of which plates 16 are fixed from above with a height H _DVL = (0.2 ÷ 0.5) R _DVL (Fig. 5), where R _DVL is the radius of the circle described by the blades 14. Opening angle helical surface of the DWL is ψ _DWL =80÷100°, (Fig. 5). The angle of rotation of multidirectional surfaces DVL is γ=90° (Fig. 5). The resulting mixture is unloaded from chamber 12 through pipe 17 into the homogenization chamber for the mixture of main components and additives.

In the chamber (Fig. 6) for mixing additives 18 (Fig. 1), from the side of loading the material, at least one pair of two-way blades 20, 21 with working helical surfaces directed towards each other is installed on the shaft 19 (Fig. 6, 7) . Behind the mentioned blades 20, 21, the same pair of blades 22 and 23 (Fig. 6) is installed, on the shaft 19, the direction of the helix of which coincides with the direction of rotation of the shaft 19. The material can be loaded into the chamber 18 from the macro mixing chamber 2 through the inlet pipe 24. In addition, for supplying heterogeneous additives into the chamber 18, it is equipped with feeders 25 and an additional inlet pipe 26 (Fig. 1, Fig. 6). In the outlet pipe 5 of the chamber 2 there is an overlapping gate 27. The unloading of the homogenized mixture from the chamber 18 or additives is carried out through the outlet pipe 28 (Fig. 6), offset relative to the axis by an angle γ _vygr =30÷50°. Between the last pair of unidirectional blades 23 and 22, an intensifying device 29 (Fig. 6) is installed on the shaft 19, made up in the form of a U-shaped frame 30 of round rods. Frames 30 have different heights and are cantilevered on shaft 19 parallel to its horizontal axis. At the same time, the frames are displaced around the axis of the shaft 19 along the circumference in the direction opposite to its rotation (Fig. 8), and the largest displacement angle of the extreme U-shaped frames is ξ _P =50÷90°.

_сф.=70-110°.The chamber for homogenization of the mixture of main components and additives 31 (Fig. 9), located on the same vertical axis with chamber 2, is connected by nozzles 32 and 33 (Fig. 9, Fig. 10) to the micromixing chamber 12 and the mixing chamber of additives 18. In the supply pipe additives 33 are vertically installed supply gates 34. Inside the chamber 31, on the loading side, are located, in an internal chamber 35 coaxially installed relative to the chamber 31 body, on the shaft 36 a pair of two-way blades (DVL) 37, 38 (Fig. 9). Working helical surfaces DVL 37, 38 are directed towards each other. For a pair of DVL 37, 38 is fixed on the shaft 36, adjacent to them, DVL 39 directional. The unloading blade 40 is installed in the unloading zone of the chamber, with the same direction of the helical surfaces of the previous blade, but displaced along the circumference in the direction of shaft rotation by an angle α=70÷90°. Between DVL 39 and blade 40 there is a device 41 for intensifying the process of mixing and microgranulating the mixture. The device 41 is made in the form of spherical cavities 43, 44 placed in opposed frame contours 42, formed by arcuate elements 45, 46 (Fig. 9, Fig. 10, Fig. 11). The device 41 is provided with a mesh cover 50 rigidly fixed on the inner parts of the spherical cavities, and the opening angle in each cavity between the extreme elements in the direction opposite to the rotation of the shaft is

_sf. =70-110°.

To obtain a microgranulate from a homogenized composite mixture, a fitting 48 is installed in the chamber 31 in the end surface for introducing a binder in a sprayed or vapor state into the inner chamber 35 with double-threaded helical blades (DVL) 37, 38, 39, and on the chamber body 31 there is a fitting 49 for the output of the steam-air mixture (Fig. 9).

Recirculation mixer combined action works as follows.

The original components of the composite mixture, such as cement and pre-activated silica, enter the receiving hopper 1 and then through the inlet 3 into the chamber 2 macromixing. For intensive homogenization of the main components of the mixture, constituting up to 80÷90% of the entire composite mixture, in chamber 2, single-threaded helical blades (SVL) 7 of multidirectional action are installed, providing intensive internal recycling of material flows, both in the space between the SVL 7 themselves and between the rods 8 blades 7 of which they are made. To improve the quality of mixing between OVL 7 on their working surfaces, plates 10 are fixed with a height of H _OVL =(0.2÷0.5)R _OVL , where R _OVL is the radius of the circle described by the blades (Fig. 3). At lower values, H _OVL <0.2R _OVL , the material flow velocity under the influence of the backwater of the supplied material is insufficient, and at H _OVL >R _OVL , on the contrary, the flow rate is high to ensure high-quality mixing of heterogeneous (dissimilar) components.

To ensure high-quality macro-mixing of the mixture, the opening angle of the intermittent helical surface OVL 7 should be β=160÷200°. At lower values, β<160°, the effect of OVL on the homogenized mixture is not sufficient. At β>200°, the working surfaces of the blades overlap each other, the mixing process deteriorates.

After macro-mixing in chamber 2, the mixture from the discharge pipe 4 enters through the pipe 11 into the micro-mixing chamber 12, in which an intensive process of micro-mixing (homogenization of individual local volumes) of the mixture is implemented, due to pairwise installed multidirectional double-threaded helical blades (DVL) 14, 15, 16, fixed bushings-collars 9 on the shaft 13 (Fig. 2, Fig. 4).

To ensure high-quality homogenization of the mixture in the chamber 12 on the working surface (DWL) 14,15,16, plates with a height H _DWL = (0.2÷0.5)R _DWL are installed, where R _DWL is the radius of the circle described by the blades 14-16. The opening angle of screw DVL 14, 15, 16 must be within ψ _DVL =80÷100°. In the case of ψ _DWL <80°, the effect of DWL on the homogenized mixture is not sufficient. When ψ _DWL >100° the working surfaces of the blades overlap each other, the mixing process deteriorates.

At the same time, the physical effects on the homogenized mixture, which are characteristic of RWL and DWL, are taken into account both at the stage of macromixing and micromixing. In the case of the use of OVL, a double impact of the blade on the material is realized in one revolution of the shaft, and a 4-fold impact of the blade when using DVL is also realized in one revolution of the shaft. The angle of rotation of the multidirectional surfaces of the DVL 14-16 is γ=90° (Fig. 5), which ensures uniform movement of the mixture in the chamber 12 and the unloading of material from it through the nozzle 17.

To obtain high-quality composite mixtures, especially with heterogeneous components and various additives (plasticizing components, pigments, stabilizing or heat-fire-resistant components, etc.), it is necessary to use not only highly efficient paddle devices that exclude "stagnant zones" in the mixed mixture, but also to ensure rational technological scheme of homogenization of the additives themselves and their introduction with the fundamental main components of the mixture into the mixer chambers. The most rational way is the parallel preparation of the main components (their macro and micro mixing up to 80-90%), mixtures and intensive homogenization of low-percentage (10-20%) additive components in a separate chamber.

From macromixing chamber 2 with OVL 7, the homogenized mixture can be supplied both to micromixing chamber 12 through pipe 4, and to chamber 18 for mixing additives through pipe 5. To change the supply of a mixture of common components from chamber 2 to chamber 18 or to exclude this process in the discharge pipe 5 (Fig. 1), a slide device 27 is used. When homogenizing only additives in chamber 18, gate 27 blocks the flow of the mixture from chamber 2.

The process of micro-mixing of the mixture components is carried out in the chamber 12. The mixture through the loading pipe 11 from the macro-mixing chamber 2 enters the micro-mixing chamber 12. Multidirectional DVL 14, 15, 16 carry out intensive homogenization of the mixture in the working space between them during their fourfold impact in one revolution of the shaft. Taking into account that after the macromixing chamber the process of homogenization by single-pass helical blades leads to the saturation of the homogeneity criterion according to the exponential dependence, then in order to increase the mixing efficiency, a more intense effect is required, which is ensured by a more developed surface of the DWL and a larger number of operating cycles for a given period of time. In the chamber of macro-mixing 2 and micro-mixing 12, when implementing the internal recycling of the material, respectively, its movement is carried out due to the support of the loaded mixture.

When the mixture is homogenized in chamber 18, from feeders 25 through an additional inlet pipe 26 (Fig. 1, Fig. 6) heterogeneous additives enter chamber 18 equipped with DVL 20, 21, 22 and 23 (Fig. 6) and a frame intensifying device 29 (Fig. 6, Fig. 8).

Double-threaded helical blade DVL 20 in the chamber 18 (Fig. 6) provides, together with DVL 21, recirculating mixing of the components in the internal space between them, as well as, through DVL 22, the movement of the material in the direction of unloading. Between DVL 22 unidirectional action and 23 is a frame device 29, providing intensive mixing of the components.

Intensive mixing is ensured by the developed surface of the device 29, composed of U-shaped frames rigidly fixed to the shaft 19 coaxially. At the same time, the displacement of the frames relative to the shaft in the direction opposite to its rotation, on the one hand, provides a "capturing effect" on the material due to the adjacent internal cavities ("pockets") formed from the frames, and on the other hand, the intensifying effect of the round rods that make up the U-shaped framework. In addition, the arrangement of the frames with their larger side along the axis of the shaft and acting on the mixed components of the mixture in the radial direction (toward the side surface of the chamber 18) provides a sufficiently long exposure to obtain a homogenized mixture.

_П=50-90° (фиг. 7), обеспечивающий вполне достаточный объем внутренних полостей для интенсифицирующего воздействия стержней П-образных рамок. При меньших значениях угла

_П<50° интенсифицирующее воздействие недостаточно, при больших значениях

_П>90° - процесс интенсификации смешения снижается за счет взаимного воздействия движущихся слоев материала.The above is also facilitated by the displacement of the extreme U-shaped frames at an angle

_P =50-90° (Fig. 7), providing quite sufficient volume of internal cavities for the intensifying effect of the rods of the U-shaped frames. For smaller angles

_P <50° intensifying effect is not enough, at high values

_P >90° - the process of intensification of mixing is reduced due to the mutual influence of moving layers of material.

In chamber 31 (Fig. 1, Fig. 9), located on the same vertical with chamber 2, an internal chamber 35 (Fig. 9) is installed for the final homogenization of the composite mixture with additives, connected by nozzles 32 and 33 (Fig. 9, Fig. 10 ), respectively, with a micro-mixing chamber 12 and a mixing chamber of additives 18. In the branch pipe 33 for supplying additives, supply flashers 34 are installed vertically, ensuring a uniform supply of the mixture into the chamber 31 and sealing the supply device. The branch pipe 33 for supplying homogenized additives from the chamber 18 or, if necessary, homogenized at the first stage in the micromixing chamber 2 of the initial mixture is connected to the inner chamber 35, in the loading zone.

In the inner chamber 35, installed coaxially inside the chamber 31, along its horizontal axis, a pair of two-way multidirectional blades 37 and 38 are located on the shaft 36 (Fig. 9, Fig. 10). The working helical surfaces of the blades are directed towards each other, which ensures intensive mixing of the mixture in their internal space. Behind the specified pair of DVL 37, 38, in the direction of the mixture, there is also a two-way blade 39 fixed on the shaft with the direction of the helix of the blade 37, which moves the material towards the unloading. A similar unloading helical blade 40 is installed in the mixture unloading zone, but with a larger diameter of the circumscribed circle corresponding to the chamber 31 (Fig. 9, Fig. 10).

Between the unloading blades 39 and 40 in the chamber 31 on the shaft 36 there is an intensifying device 41 for the mixing or microgranulation process (if necessary), displaced with respect to the DVL 39 around the circumference, in the direction of the shaft rotation, at an angle α=70-90°. When α<70° or α>90°, the conditions for loading the mixture with the blade 39 into the device 41 worsen (Fig. 10).

Device 41 is made in the form of spherical cavities 43, 44 placed in opposed frame contours 42, formed by arcuate elements 45, 46 (Fig. 9, Fig. 10, Fig. 11). The spherical surface of the blades 43, 44 (semicircles) provides favorable conditions for micro-granulation of particles, taking into account their movement in the three-dimensional space XYZ from the periphery to the center of the device 41. This granulating (rolling) effect on the particles in the spherical cavities 43, 44 is enhanced by periodically repeating the movement of material flows from one adjacent cavity to another. To ensure the specified movement of the material in the spherical cavities and avoid spillage of the formed microgranulate, a mesh coating 50 is rigidly fixed on their inner surface, with a cell size corresponding to the average diameter of the microgranulated particles.

_сф.=70-110° с максимальным R_max и минимальным R_min радиусами (фиг. 9, фиг. 11).The opening angle in each cavity between the extreme elements in the direction opposite to the rotation of the shaft is

_sf. =70-110° with maximum R _max and minimum R _min radii (Fig. 9, Fig. 11).

The value of the opening angle of each cavity is determined by the impact zone of the device 41 on the homogenized mixture along the perimeter of the chamber 31 for the final homogenization of the mixture.

_сф.<70° - воздействие минимально, при

_сф.>110° действие смежных и разнонаправленных сферообразных полостей накладывается друг на друга. Процесс гомогенизации смеси ухудшается. С увеличением значений угла

_сф. воздействия устройства 41 на смесь (микрогранулят) возрастает.At

_sf. <70° - the impact is minimal, at

_sf. >110° the action of adjacent and differently directed spherical cavities is superimposed on each other. The process of homogenization of the mixture deteriorates. With increasing angle values

_sf. the impact of the device 41 on the mixture (microgranulate) increases.

If it is necessary to obtain a microgranular material (for mixtures prone to spontaneous segregation - stratification according to granulometry, caking during storage, water absorption, etc.), the inner part of the spherical cavities 43, 44 formed by arcuate elements 45, 46 is equipped with a rigidly fixed mesh coating 50, with cell size corresponding to the average diameter of microgranular particles (Fig. 9, Fig. 11).

In this case, to enhance the adhesive interaction of granulated particles, in the upper semicircle of the end surface of the inner chamber 35 (Fig. 9) there is a fitting 48 for supplying a sprayed or vaporous binder, which is evenly distributed by two-way blades 37, 38, 39 over the volume of the homogenized mixture. When using a vaporous binder, its residue is removed through an opening in the upper part of the housing 36 through a tube 48 for dumping excess steam.

To ensure uniform unloading of the homogenized mixture from chambers 18 and 31 (Fig. 6, Fig. 9) or microgranulate from chamber 31 (Fig. 9), the displacement angle γ of the unloading _DVL relative to the intensifying devices 29, 41 (as well as microgranulation - pos. 40 ), in the direction opposite to their rotation, is γ _vygr =30÷50° (Fig. 7, Fig. 10). If this condition is violated (γ _extrusion <30° and γ _extrusion >50°), the uniform unloading of the material is disturbed.

When a homogenized dry or moistened mixture with additives is unloaded by a two-way helical blade 39 from the inner chamber 35 (Fig. 9), the material is captured by the side plates of the frame contour 41 and enters the spherical cavities 43, 44, uniformly rotating around the horizontal axis of the shaft (Fig. 9, Fig. . eleven).

In this case, the particles of the homogenized mixture are subjected to volume-spatial effects from the arc-shaped elements forming spherical cavities. This, in turn, leads to an intensification of the process of homogenization of the composite mixture.

A similar intensification of the process of homogenization of the mixture is implemented in the frame device 29 (Fig. 6), composed of U-shaped rods, offset relative to each other around the horizontal axis of the shaft. However, in this device, the particles are not subjected to a rolling effect, due to their movement along the arcuate surface and between the U-shaped rods, which ensures the intensification of the process of homogenization of composite additives.

_сф=70÷110°, что обеспечивает необходимые объем для гранулообразования и степень подвижности гранулированных частиц. При

_сф<70° и

_сф>110°, указанные условия нарушаются. Выгрузка гранулята, сформованного в сферообразных полостях лопастей 43, 44, осуществляется через верх крайней боковой пластины рамочного контура 42, в сторону ДВЛ 40 (фиг. 9).The process of microgranulation of the mixture components and additives is carried out as follows. The components of heterogeneous additives pre-moistened and homogenized in the chamber 35 are loaded with the help of an unloading blade 39 into the intensifying mixing and microgranulation device 41. At the same time, the spherical surface of the blades 43, 44 (semicircles) provides favorable conditions for microgranulation of particles, taking into account their movement in the three-dimensional space XYZ from periphery to the center of the device 41. This granulating (rolling) effect on the particles in the spherical cavities 43, 44 is enhanced by the periodically repeated movement of material flows from one adjacent cavity to another. To ensure the specified movement of the material in the spherical cavities and to prevent spillage of the formed microgranulate, a mesh coating 50 is rigidly fixed on their inner surface, with a cell size corresponding to the average diameter of the microgranulated particles. The opening angle of each spherical surface of the blades 43, 44 (Fig. 11) is

_sf =70÷110°, which provides the necessary volume for granulation and the degree of mobility of granular particles. At

_sph <70° and

_sf >110°, these conditions are violated. The unloading of the granulate, formed in the spherical cavities of the blades 43, 44, is carried out through the top of the extreme side plate of the frame contour 42, towards the DVL 40 (Fig. 9).

The latter ensures the selection of finished products from the intensifying device 41 and unloading through the pipe 51.

Thus, the recirculating mixer of combined action (Fig. 1) has various technological possibilities for implementing the processes of homogenization of composite mixtures: macro and micro mixing in chambers 2 and 12, mixing of heterogeneous composite additives in chamber 18 with an unloading pipe 28, as well as obtaining a composite mixture ( macro and micro mixing) with heterogeneous components and additives (pos. 2, 12, 18 and 31).

Claims (5)

1. Recirculation mixer, characterized in that it contains a hopper, installed under the hopper chambers for macro-mixing, micro-mixing, homogenization of a mixture of main components and additives, mixing additives, having shafts located in them, bearing paddle devices limited by an intermittent helical surface of various geometric profiles and interconnected by loading and unloading nozzles, while the macromixing chamber is connected to the hopper, its helical blades are made of single-thread, multidirectional action and are made up of rods rigidly fixed on the shaft, and there are plates on the working surface of the blades, and the macromixing chamber is connected by means of its discharge nozzle to the loading pipe of the micromixing chamber, while in the micromixing chamber the helical blades are made of two-way, multidirectional action and are composed of rods, on the working surface of which there are also plates on top, and The mixture obtained in this chamber is unloaded through the discharge pipe into the homogenization chamber for the mixture of main components and additives, which is located on the same vertical axis as the macromixing chamber, connected to the additive mixing chamber, and the additives are fed into it through the supply gates of the chamber body, while coaxial to the body of the homogenization chamber, inside it there is an internal chamber with a diameter of d _V.K. =(0.4÷0.7)D _K.G. and length L _V.K. =(0.3÷0.5)L _K.G. , where D _K.G. and L _K.G. - the inner diameter and length of the homogenization chamber, in which a pair of two-way blades is installed on the shaft from the loading side, the working surfaces of which are directed towards each other, and behind these blades on the shaft there is a two-way directional blade adjacent to them, and also in the unloading zone from the chamber - an unloading blade with the same direction of the helical surfaces of the previous blade, displaced along the circumference in the direction of rotation of the shaft at an angle α=70-90, and between the directional blade and the unloading blade there is a device for intensifying the mixing process and microgranulation of the mixture, made in the form of placed in opposed frame contours of spherical cavities formed by arcuate elements, while the opening angle in each cavity between the extreme elements in the direction opposite to the rotation of the shaft is

_sph = 70-110°, in addition, the additive mixing chamber is connected by nozzles to the macro-mixing chamber and the homogenization chamber, at least one pair of two-way blades with working helical surfaces directed towards each other is installed in the additive chamber on the side of loading materials, behind these blades the same pair of blades is installed on the shaft, the direction of the helix of which coincides with the direction of rotation of the shaft, the material is loaded into the additive chamber from the macromixing chamber through the inlet pipe, while for feeding heterogeneous additives into this chamber it is equipped with feeders and an additional inlet pipe, and the unloading of the homogenized mixture from the additive chamber is carried out through the outlet pipe, and between the last pair of blades unidirectional with the shaft, an intensifying device is installed on the shaft, made in the form of U-shaped frames of rods of circular cross section, the frames have different heights, fixed cantilevered on the shaft lu parallel to its horizontal axis and displaced around the axis of the shaft in a circle in the direction opposite to its rotation, while the largest angle of displacement of the extreme U-shaped frames is

_P \u003d 50-90 °. 2. The mixer according to claim 1, characterized in that plates with a height are fixed along the outer working surface of the rods of single-thread and double-thread helical blades, respectively H _OVL = (0.2 ÷ 0.5) R _OVL and H _OVL = (0.2 ÷ 0.5)R _DVL , where R _OVL , R _DVL are the radii of the circles described by single-start and double-start blades, respectively. 3. Mixer according to claim. 1, characterized in that the rigid fastening of single-threaded and double-threaded blades on the shafts is provided by detachable bushings - clamps. 4. The mixer according to p _. unloading two-way blades relative to intensifying mixing devices in the direction opposite to the rotation of the shaft is γ _vyg. =30÷50°. 5. The mixer according to claim. 1, characterized in that in the loading pipe of the homogenization chamber of the mixture of the main components and additives, sealing shutters-flashers are installed, and in the body of the inner chamber there is a fitting for supplying and discharging the binder in a sprayed or vapor state, while in the intensification device during the mixing process, the inner part of the spherical cavities formed by arcuate elements is provided with a rigidly fixed mesh coating.

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