RU2257294C1 - Method of production of cement-water suspension and device for realization of this method - Google Patents

Abstract

FIELD: manufacture of building materials; production of cement-water suspension and products on its base: cement stone, mortars and concretes.

SUBSTANCE: proposed method makes it possible to ensure activation of cement particles from cement-water suspension under conditions of statically smooth distribution of water in suspension over surface of cement fractions when surfaces of coarse, medium and fine particles adsorb such amount of water which they are able to hold at mixing. Proposed method includes mixing of hydraulic binder, mainly cement, with water or with filler and water at physico-chemical activation of cement in composition of cement-water suspension obtained in mixing unit in field of centrifugal forces. Activation is performed with cavitation intensified by blowing and bubbling the suspension with compressed air at regulation of mixing time. Magnitudes of cavitation φ are within range of 3.8 to 0.6.10^-4. Cavitation number is determined from the following formula: φ=[(k₁Δ+k₂ΔP)η]/2π²gp²R³n,,where k₁ is coefficient of loss of pressure head in mixing unit at cavitation which is equal to 0.55-0.8; ΔH is difference between hydraulic pressure head in mixing unit and pressure of saturated steam in cavities at 20°C equal to 0.03 MPa characterizing the cavitation field and selected within 0.25-1.2 MPa; k₂ is coefficient of loss of pressure head of blown compressed air which is equal to 0.5 in the average; ΔP is difference between pressure of blown compressed air and pressure of saturated steam in cavities selected within 100-250 kPa; η is present viscosity of cement-water suspension being prepared or products on its base which is maintained within 16-1770 Pa·s and within 20-130 Pa·s during bubbling; ρ is present density of said cement-water suspension or products on its base, kg/cm³; g is free fall acceleration equal to 9.81 m/s² ;Π is equal to 3.14; R is present radius of said field of centrifugal forces selected within 0.3-1.2 m; n is frequency of rotation of working member of mixing unit selected within 300-6000 rev/min or 5-100 s^-1; activation of suspension is continued till initial cement hydration degree reaches at least 2.5 mass-% by criterion of increment of losses at calcination from beginning of addition of water to concrete mix till its setting.

EFFECT: enhanced efficiency.

15 cl, 2 dwg, 2 tbl

Description

The invention relates to the field of building materials and products, and in particular to methods for producing a cement-water suspension and products based on it - cement stone, mortar and concrete, as well as devices for their implementation.

A number of methods are known from the prior art for producing a cement-water suspension with activation of the cement contained therein [1]. Activated cement-water suspension is used during the XX century. and nowadays, as a finished product that needs to be used quickly - before it starts to set, namely, as an injection material in geotechnics with the aim of strengthening soils, strengthening foundations and foundations, as the main material for injection piles, for repair and reconstruction works in tunnel, road, airfield, defense construction, for injection of channels with prestressed metal fittings in reinforced concrete structures, especially long ones, in other areas stva and as an intermediate product, followed by introduction of the activated suspension of fillers and aggregates by further mixing to obtain mortars and concretes in monolithic or precast construction.

An analogue of the invention in technical essence is a method for producing a cement-water suspension and materials based on it - mortar and concrete, including physico-mechanical activation of cement by means of its wet milling [2]. The method provides an increase in the strength of these materials, according to the authors, by 15-20% compared with the usual mixing of cement and water according to [1], but it is not technologically advanced: it takes at least 1 hour to clean a mill in which wet cement grinding is carried out. hourly shift, the use of disposable waste is difficult, and the resulting suspension cannot be stored for more than 1 hour - it thickens and can be set before being placed into molds or formwork [3]. The method is suitable mainly for the manufacture of large-sized structures such as bridge spans with a long concreting time.

More compact is the method of producing a cement-water slurry and materials based on it, including the activation of cement by means of a grinder in a vibratory mill. Starting from the pioneering work [4], this method was widely used in the USSR in the 50s and 60s [5-7]. The method provides the following advantages [8, 9]: a) activation of the particle surface of the clinker component of cement, on which new active centers appear, which increases the cementitious properties of the cement and allows either to increase the strength of the hardened cement-water suspension, that is, cement stone and other materials its basis, including mortar and concrete, or reduce cement consumption in these materials of equal strength and increase the proportion of aggregates (aggregate cement); b) elimination of air shells on cement particles arising from the pneumatic conveying of cement through pipelines at a cement plant from mills to silos, and from the latter into wagons, as well as during aeration of silos during cement storage; these shells impede water access to cement particles and the distribution of the latter over their surface; c) activation of the interaction of gypsum stone particles contained in cement with water, which increases the hardening rate and strength of hardened cement-water slurry, cement stone, mortar and concrete [9]. However, the cement vibration breaker turned out to be operational only at low productivity (up to 3 m ³ / h in cement-water suspension output) [8] and could not be used in powerful technological lines for the production of both monolithic and precast concrete and reinforced concrete. This was clear to many researchers from the very beginning, so the vibrational activation of the cement-water suspension developed in parallel with the non-vibrational technological methods of cement activation in its composition.

So, other analogues of the invention are known in which the specified activation of cement in the suspension is carried out in the field of centrifugal forces [10-12], providing, according to the authors, the same advantages as a vibrodomol, but with technologically more reliable activators. Moreover, the productivity of the processing line can be significantly higher - up to 10 m ³ / h. However, the corresponding mixers - “vortex hydrator” [10], centrifugal activator [11] and high-speed turbulent activator [12] after a long check in the production environment were considered insufficiently durable and unsuitable for continuous operation, primarily due to: a) the inability to prepare cement -water suspensions with low W / C values (0.2-0.25), for which they were originally intended, since it was shown that with rapid mixing of suspensions with low W / C values in the specified field cabins discontinuities and reduces the uniformity of the material [13]; b) in connection with the rapid overgrowth of mixing devices by hardening hydrated neoplasms, the cleaning of which is very time-consuming; the quality of the materials obtained under such conditions turned out to be subject to significant fluctuations [14]. In [13], it was concluded that for these reasons, the activation of centrifugal forces in the field must be combined with vibration treatment to reduce the viscosity and ultimate shear stress of the cement-water suspension.

The next step in this regard was a method for producing a cement-water slurry, including the so-called “vibration activation of cement paste”, which is mixing cement with water at a W / C value corresponding to approximately 0.8 of the W / C value with normal density of the cement paste, processing the obtained cement paste with a deep vibrator for 3-10 minutes, and after the achieved thixotropic liquefaction of the specified paste by re-mixing, with the introduction of fine aggregate, in particular with an additional hydrochloric activation [15]. To implement the latter, the Azerbaijan Polytechnic Institute has proposed pumping a homogenized suspension of cement and sand with water with an impact on the barrier after a special centrifugal pump [16]. Despite the significant increase in the quality of the cement mortar achieved by activating the mixing according to the method [15, 16] in additional mixers, the opinion [13, 14] is known about the low reliability of two-unit mixing according to the method [15, 16] due to the increased laboriousness of the cleaning operations of the two devices instead one and the advisability of combining the operations of mixing and vibrating in one apparatus.

Indeed, such methods and their corresponding apparatuses, namely vibration mixers, in which the specified activation of a cement-water suspension is carried out in a centrifugal force field combined with vibration, have been developed [17–20], and the corresponding devices have been less prone to pollution and overgrowing . In them, the aforementioned “cement gel”, due to vibration, thixotropically liquefying, surrounds crystalline hydrate neoplasms and, according to the authors, does not allow these neoplasms to irreversibly overrun mixing containers [19, 20]. Additives of surface-active substances, in particular, technical lignosulfonates at that time in the form of sulfite-alcohol stillage, which additionally “peptize” (impart submicroscopic sizes) [13, 21] to the main elements of the cement submicrostructure, contribute to the indicated dilution and decrease in the overgrowth of mixing containers stone - calcium hydrosulfoaluminates (fibers), calcium hydrosilicates (gel with a C / S basicity of less than 1.5 and submicrocrystalline fibers with a C / S basicity of 1.5 or more), residual calcium hydroaluminates (microcrystals) and free calcium hydroxide, in particular, with an admixture of silica (microcrystals and X-ray amorphous gel, respectively) [22] and form from these gels a matrix that forms the basis of the strength of the cement stone, while the crystalline and fibrous part of the latter represents island intergrowths, which determine the strength of cement stone only in the initial stages of hardening, when the gel content is low. These intergrowths are capable of fouling the mixers either during false setting of cement, which occurs when hydroaluminates or dicalcium sulfate crystals predominate in its hydrate neoplasms, or in the absence of cement activation, since the proportion of gels in its hydrated neoplasms increases by a factor of 2–3 in comparison with the hydration of non-activated cement in conditions of single-stage mixing of the latter with water.

Closest to the invention is a method for producing a cement-water slurry, as well as hardened products based on it - cement stone, mortar and concrete, including mixing a hydraulic binder, mainly cement with water or filler and water with physico-mechanical activation of cement in the composition obtained in the mixer cement-cement slurry, in which the specified activation of the cement is carried out in a centrifugal force field combined with vibration, namely, mix the cement with water or cement with water and part of the filler (ground sand) at W / C in the range of 0.25-0.4, combining mixing with the vibration of the resulting suspension with an oscillation frequency in the range of 100-230 s ^-1 with an amplitude of the latter, respectively, in the range of 0.5 -0.3 mm, adding, if necessary, even in the absence of vibration, at least the rest of the filler, and sometimes the filler [23]. It is recommended to use finely ground or ground cement, in particular, with a specific surface of 500 m ² / kg or more. This method allows to increase the strength of products obtained on the basis of the specified suspension, namely cement stone, mortar and concrete based on it in comparison with single-stage mixing, known from the prior art, by about 10-15 MPa, ceteris paribus [13, 24 ], in particular, without increasing the consumption of cement in mortars and concrete. This method, like its predecessors, did not receive wide industrial use due to the complexity of the design and the impossibility of long trouble-free operation of the mixing device with vibrating blades. If only the mixer body is subjected to vibration [21], then the efficiency of the method is reduced by at least half, and the weak point is the articulation of the body with the drive shaft and blades attached to it.

The main common drawback of all known methods for producing a cement-water suspension and products based on it - cement stone in the broad sense (hardened injection mortars, etc.), as well as mortar and concrete, including vibration processing directly with stirring of the suspension, is the lack of statistical averaging the distribution of water over various fractions of cement. The fact is that the granulometric composition of cement is heterogeneous: with an average cement particle size of 12-15 microns, it contains (in wt.%) From 2 to 15 particle fractions larger than 80 microns and from 3 to 35 particle fractions less than 5 microns [24] . At the same time, the fine fractions of cement contain more calcium and gypsum aluminates compared to the rest, and in this connection, when mixed with water and subsequent hardening, they form much more hydrated hydrates and, due to the high specific surface, interact much faster with water. At the same time, all known methods for preparing a cement-water suspension not only do not ensure uniform distribution of water between the cement fractions in accordance with their specific surface, but, on the contrary, form a suspension structure in which large pores with a high content correspond to particles of a large fraction water, as shown by direct measurements, Shestoperov, Lyubimova and Fedner [25]. The latter, remaining free, in the hardened cement stone forms a system of capillaries, which are stress concentrators from external loads, which reduce strength characteristics. In addition, diffusion from the outside of environmental corrosive agents occurs in a system of such capillaries [26]. Thus, the uneven distribution of water between the fractions of cement in a cement-water suspension causes a decrease in the level of the whole complex of construction and technical properties of cement stone and other products based on it.

Other common drawbacks of all methods of producing a cement-water suspension and products based on it - cement stone in the broad sense (hardened injection mortars, etc.), as well as mortar and concrete, including vibration processing directly when mixing this suspension, is the instability of the corresponding equipment [27] and the exposure of the technical personnel serving this equipment to vibration diseases [28], and the danger of the latter increases with increasing frequency of vibration . Moreover, as the practice of using the methods [17-23, 27] has shown, the main technological reason for the lack of their widespread introduction, in addition to mechanical imperfections, is nevertheless overgrowing of mixing devices during the preparation of a cement-water suspension by cement hydration products due to the fact that their working chambers are not vibrated zones and adjacent overgrowing sections of the inner surface of their buildings.

The objective of the invention in terms of a method for producing a cement-water suspension, as well as these materials based on it, is to ensure the activation of cement particles in a statistically uniform distribution of water in the suspension over the surface of the cement fractions, in which the surfaces of both large and medium and small particles of cement adsorb exactly as much water as they can hold with stirring. This position can be called the Shestoperov condition, which he tried to formulate in the indicated paper [25], but could not be realized. It guarantees a significant increase in the uniformity and quality of both the specified suspension and the specified materials based on it. This achieves a significant increase in the manufacturability of the method, as well as the service life of the equipment compared to the prior art.

The problem is solved in that in a method for producing a cement-water suspension, comprising mixing a hydraulic binder, mainly cement, with water or with a filler and water with physico-mechanical activation of cement in the composition obtained in a mixing device in the field of centrifugal forces of a cement-water suspension , the specified activation is carried out with cavitation, intensified by blowing the specified suspension with its sparging with compressed air while regulating, at least for part of the time mixing, the number of cavitation numbers φ in the range from 3.8 to 0.6 · 10 ^-4 , while the number of cavitation is determined by the formula:

where k ₁ - coefficient of pressure loss of the mixing device during cavitation, equal to 0.55-0.8;

Δ N is the difference in the hydraulic pressure of the mixing device and the pressure of saturated water vapor in the caverns at 20 ° C equal to 0.03 MPa, which characterizes the cavitation field and is selected in the range 0.25-1.2 MPa;

k ₂ is the pressure loss coefficient of the blown-in compressed air, equal to an average of 0.5;

Δ P is the pressure difference between the pressurized compressed air and the pressure of saturated water vapor in the caverns, selected in the range of 100-250 KPa;

η is the current viscosity of the prepared cement-water suspension or products based on it, maintained in the range of 16-1770 Pa · s, and during bubbling in the range of 20-130 Pa · s;

ρ is the current density of the specified cement-water suspension or products based on it;

g is the acceleration of gravity equal to 9.81 m / s ² ;

π - 3.14;

R is the current radius of the specified field of centrifugal forces, selected in the range of 0.3-1.2 m;

n is the frequency of rotation of the working body of the mixing device, selected in the range of 300-6000 rpm, or 5-100 s ^-1 ,

and the specified activation of the suspension is carried out until the degree of initial hydration of the cement is achieved according to the criterion of an increase in losses during calcination from the beginning of mixing of the suspension to the moment of its setting, at least 2.5 wt.%.

In an embodiment of the invention, a material from the group of Portland cement, slag Portland cement, sulfate-resistant Portland cement, pozzolanic Portland cement, low water demand cement, expanding or non-shrink cement, these cements based on promoted clinkers, mixtures of these cements are used as the specified cement.

In another embodiment of the invention, said filler is introduced into the suspension during and after cavitation.

In a further embodiment of the invention, a powder material with a specific surface according to the method of breathability in the range of 200-1500 m ² / kg is used as a filler.

In an embodiment of the invention, ground sand or cullet or brick fight or fly ash at wt. the ratio of the clinker part of the specified cement and the specified powdery material from 1: 0.05 to 1: 1.

In another embodiment of the invention, a fine aggregate is additionally introduced into said suspension during cavitation and / or after its completion.

In a further embodiment of the invention, standard sand or particularly fine sand or silty sand or sand dune, or mixtures thereof, by weight, are used as said fine aggregate. the ratio of the specified cement and the specified fine aggregate from 1: 0.3 to 1: 4.

In an embodiment of the invention, a commodity dry mixture of a hydraulic binder, filler, filler and additives is added to the specified suspension during cavitation and / or after its completion. the ratio of the specified cement and hydraulic binder in the composition of the specified dry mix from 1: 0.1 to 1:15.

In another embodiment of the invention, the average specific energy intensity of the field of centrifugal forces in the preparation of the specified suspension with sparging is selected in the range of 1.8-25 kJ / m ³ .

In a further embodiment of the invention, additives for concretes from the groups are additionally added to the specified suspension in the process of bubbling or at the end of it: I — plasticizing, or water-reducing; II - water retention, or improving pumpability; III - retarders setting and hardening; IV - accelerators setting and hardening; V - clogging pores; VI - gas generating; VII - air entraining; VIII - antifreeze; IX - hydrophobic, in concentrations of 50-70 wt.% Their optimal values, selected in the conditions of free access of atmospheric carbon dioxide, and / or anti-shrink additives, the inorganic basis of which are sulfoaluminate clinker and / or aluminum sulfate, additionally including a peptizing component, and namely, a mixture of an organic etchant and a film former, when the mass ratio of the inorganic base and the specified ingredients in the anti-shrink additive 100: (0.5-20) :( 0.3-15) and the mass ratio of Portland cement second portion of clinker in cement and antisettling additives introduced into the suspension or tsementovodnuyu products on its base 100: (0,6-3,5).

In an embodiment of the invention, sodium or calcium polymethylene polynaphthalene sulfonates or technical modified lignosulfonates or technical modified lignosulfonates are taken as plasticizing or water-reducing additives, water-retaining or melt-oxidizing agents are used as water retention or improvement of pumpability additives. potash or chloride are used as setting and hardening accelerators calcium or sodium chloride or aluminum chloride or sodium sulfate or trisodium phosphate or mixtures thereof, aluminum sulfate, ferrous sulfate, ferric chloride are taken as additives that clog pores, aluminum powder or hydrogen peroxide mixed with calcium oxychloride are taken as gas-forming additives, as air-entraining additives take saponified wood resin or neutralized air-entraining resin or sodium ethylsiliconate; as antifreeze additives take sodium nitrite or calcium nitrite-nitrate-calcium chloride, as hydrophobic additives, take a solution of high molecular weight fatty acids in mineral oil or polyhydrosiloxanes, and as anti-shrink additives take a mixture of the first inorganic base of the latter - sulfoaluminate clinker, which includes at least 30 wt.% calcium sulfoaluminate, and a peptizing component - the etchant and film former mannuronic acid and calcium stearate, or a mixture of the second inorganic base of anti-shrink additives - aluminum sulfate and the specified peptizing th component.

In another embodiment of the invention, said suspension is subjected to additional mixing with the introduction of coarse aggregate or a mixture of coarse and fine aggregates, as well as water and preparation of mortar or concrete mixtures, including hydrated neoplasms of cement obtained during said preliminary activation, as seeds.

In a further embodiment of the invention, materials of the following groups are used as said fine and / or coarse aggregates: I of natural origin, including silicate rocks and / or minerals, in particular granite and / or quartz, and / or carbonate rocks, in particular , limestone and / or dolomite, and / or II, of artificial origin, prepared from expanded rocks, including aluminosilicates, in particular expanded clay or vitreous or perlite, or from artificial porous materials, in particular foam.

The essence of the invention in terms of a method for producing a cement-water suspension is the advantages of intensified cavitation before vibration during the activation of cement in the composition of the cement-water suspension.

случаях из 10 является нулевой в каждый данный момент времени. Формулировка теоремы Герланда, принятая в отечественной литературе, такова [30]: “Непрерывно протяженная одномерная фаза (линия), проходящая через весь объем структуры в одном направлении, с вероятностью, отличной от нуля, занимает не менее 1/5 общего объема структуры”. Иными словами, в двухфазной системе, включающей, в частности, твердую и жидкую фазы, где последняя занимает не менее 20% по объему, при случайном распределении фаз по объему структуры вероятность в каждой точке структуры найти обе фазы превышает нуль. Следовательно, принимая, как обычно, см. главы 1 в работах [30], твердые фазы за единую фазу, а жидкость - за вторую фазу, главным условием ненулевой вероятности присутствия обеих фаз в любой точке системы, или, в данном случае, суспензии, является случайный характер распределения воды в системе (более строго - распределение воды в системе по Пуассону). При вибрационной активации суспензии процесс активации, распространяющийся на 10% объема суспензии в каждый данный момент времени, является процессом с предысторией, то есть активация каждой порции суспензии в ее объеме зависит от активации предыдущей, тем самым случайный характер процесса активации не обеспечивается. При кавитации активируется одновременно весь объем указанной суспензии, что гарантирует отсутствие предыстории процесса в каждой точке суспензии (характеристика марковской цепи [31]), при этом условие случайного характера процесса выполняется, тем самым каждая частица цемента обеспечивается адекватным количеством воды. В этом, а именно в выполнении упомянутого условия Шестоперова, состоит причина повышения качества и однородности цементо-водной суспензии, получаемой по способу согласно изобретению. (Известна строгая связь между выполнением условия Пуассона для дефектов структуры и минимальным значением коэффициента вариации технических свойств материала - по Чернявскому [30]).The first of them consists in the fact that, as the distance from the working body increases, the vibration dampers in the materials being processed are proportional to their viscosity and the square of the volume fraction of the solid phase in them, while the intensified cavitation evenly affects the entire volume of the processed materials. Moreover, considering that about 10 vol. % of particles, and cavitation - about 100 vol. % of particles, and assuming that the water content in the specified suspension exceeds 20 vol. %, that is, the water-cement ratio (W / C) by mass exceeds 0.20: 3.1 = 0.065, where 3, 1 is the ratio of the densities of cement and water, based on the first stereology theorem, otherwise called Gerland's theorem [29], it seems it is possible to conclude that the probability of finding water at the surface of each cement particle during cavitation treatment is always positive, while during vibration processing it is at least

out of 10 cases is zero at any given time. The formulation of Gerland’s theorem, adopted in Russian literature, is as follows [30]: “A continuously extended one-dimensional phase (line) passing through the entire volume of the structure in one direction, with a probability different from zero, takes at least 1/5 of the total volume of the structure”. In other words, in a two-phase system, including, in particular, solid and liquid phases, where the latter occupies at least 20% by volume, with a random distribution of phases over the volume of the structure, the probability of finding both phases at each point in the structure exceeds zero. Therefore, assuming, as usual, see chapters 1 in [30], solid phases as a single phase and liquid as a second phase, the main condition for the non-zero probability of the presence of both phases at any point in the system, or, in this case, suspension, is the random nature of the distribution of water in the system (more strictly, the distribution of water in the system according to Poisson). In case of vibrational activation of a suspension, the activation process, which extends to 10% of the volume of the suspension at any given time, is a process with a history, that is, the activation of each portion of the suspension in its volume depends on the activation of the previous one, thus the random nature of the activation process is not ensured. During cavitation, the entire volume of the specified suspension is simultaneously activated, which guarantees the absence of a process history at each point of the suspension (Markov chain characteristic [31]), while the condition of the random nature of the process is fulfilled, thereby each cement particle is provided with an adequate amount of water. This, namely, the fulfillment of the aforementioned Shestoperov condition, is the reason for improving the quality and uniformity of the cement-water suspension obtained by the method according to the invention. (A strict connection is known between the fulfillment of the Poisson condition for structural defects and the minimum value of the coefficient of variation of the technical properties of the material — according to Chernyavsky [30]).

Thus, the activation of the suspension by the method according to the invention increases the uniformity of the resulting suspension and materials based on it - cement stone, mortar and concrete and significantly reduces the coefficient of variation of their construction and technical properties. In addition, in this situation, there are no untreated zones of cement-water slurry, which are always present when vibrating, and it is in contact with the latter that the surface of the mixer overgrows. In the method according to the invention this does not occur. As a result, cavitation effects can reduce by 10-15%, sometimes to a greater extent, the water-cement ratio in the suspension obtained by the method according to the invention, compared with the suspension obtained by vibration activation mixing, and even more so compared to the suspension obtained mixing without activation, known from the prior art. This factor, along with the acceleration of the interaction of cement with water in the suspension obtained according to the invention considered below, makes a significant contribution to the increase in strength and durability of materials based on the specified suspension obtained by the method according to the invention, namely cement stone, mortar and concrete.

The second advantage consists in the fact that cavitation intensified by blowing in the indicated range of cavitation numbers in the field of centrifugal forces in the activated cement-water suspension allows filling the continuity gaps formed in the last at a lower level of the average specific energy stress in the mass of the processed material compared to the centrifugal force field, combined with vibration. This provides reduced energy consumption during the implementation of the method, a fundamental (two orders of magnitude) increase in the reliability of the equipment and is the main condition for the possibility of wide industrial application of this method.

These advantages ultimately provide the main technical and economic effects of the invention.

It should be noted that a decrease in the average pore size in hardened cement-water slurry, i.e. in cement stone and products based on it, with a statistically uniform distribution of water over the surface of cement particles, reduces the carbonation rate of cement stone and materials based on it and, by an order of magnitude, reduces the intensity diffusion processes in cement stone, significantly reduces the shrinkage deformation of the latter and products based on it. So, in heavy concrete and mortar, at least a third of shrinkage and more is due to carbonation due to the presence of capillary channels [9], especially when the relative humidity is less than 60%.

For a noticeable manifestation of the indicated Shestoperov effect, experiments show that it is necessary and sufficient that, after the activation of the cement-water suspension, the degree of cement hydration in terms of the loss on ignition (hereinafter abbreviated - pp) was at least 2, 5 wt.%. In this case, carbonate birefringence of hydrated phases is usually not found in micropreparations visible under an optical microscope, and calcium hydroaluminates, judging by the values of the refractive indices and X-ray phase analysis data, are free of carbonate-contaminating ion (СО ₃ ^2- ).

Note that the phase analysis of samples of cement-water suspension to determine the degree of cement hydration in its composition is carried out using differential thermal analysis (DTA), in particular, on N. S. Kurnakov’s device in samples previously evacuated to remove free and hygroscopic moisture, and the degree of hydration is determined on the assumption that in a fully hydrated cement the content of chemically bound water in terms of the loss on ignition (pp) is on average 24% according to Kravchenko et al. versus about 28% for Co. upland and according to Taylor (all data are in [74]), since domestic Portland cements and other cements based on them contain on average less calcium aluminates and their hydration products are less watered. The degree of hydration of cement (G) is determined according to p.p. in suspension samples using DTA according to the usual methodology adopted at the Research Institute of Cement (for details, see, in particular, Ref. [75]), referring to the measured values of p.p.p. to 24% bound water with a maximum degree of hydration close to 100%.

An important consequence of the indicated advantage of the method according to the invention in comparison with the prior art is the related possibility of partial or complete replacement of long-haul aggregates from igneous rocks such as granite with less expensive ones, everywhere in the European part of Russia carbonate aggregates are available. It is known from the prior art that carbonate-type aggregates in mortars and concrete reduce the strength and durability of the latter, not only because of the reduced strength of their grains compared to, for example, granite, but primarily due to the presence of carbonate dust impurities generated during crushing, transportation and storage. It is known that this dust significantly reduces the effectiveness of standard additives for concrete, and plasticizing and water-reducing - almost to zero level [32]. This cannot be explained otherwise than primarily by the chemical effect of carbonate dust on the composition of hydrated neoplasms of cement. This is confirmed by an increase in the degree of carbonation of cement hydrated neoplasms in concretes on carbonate aggregates and a decrease in the degree of cement hydration in such concretes [12]. In addition, the carbonatization of hydrated neoplasms leads to their decomposition with the release of free water [9], which dissolves the most stressed contacts in the matrix of cement stone, which leads to recrystallization of the matrix and to strength relief of hardening cement stone, mortar and concrete [22]. The manifestation of the Shestoprov effect according to the method according to the invention, relating to the basis of concrete and mortar - cement stone - the product of hardening cement-water slurry obtained by the method according to the invention, can not only reduce all these negative effects, but also prevent their manifestations, which was found in studies of the authors of the present invention. And this opens up the possibility of more efficient use of carbonate aggregates in mortars and concrete. It should be added that the old successful work of A.S. Panteleev of the 50s of the XX century on the replacement of part of the clinker component in cement with limestone flour with particles of 40-120 microns in size and, accordingly, on the replacement of part of silicate aggregates in limestone concrete, as it became clear in recent years, they relate to the special case of the use of highly alkaline [R ₂ O = (Na ₂ O + 0.658 K ₂ O) ≥ 0.8% by mass] and high aluminate (C ₃ A≥ 8% by mass) clinkers as a cement base and are only private technical solutions. Moreover, the method according to the prototype, as it was found, only in such individual cases can provide an increase in the content of limestone fillers in cement or a partial replacement of silicate fillers with limestone in concrete in connection with too few carbonate seeds in the composition of the products of initial cement hydration and their insignificant effect on the final degree of carbonation of the products of the main process of cement hydration in hardening cement stone, and accordingly in mortar and concrete e. The method according to the invention for the first time on any cements can contribute to the indicated substitutions, the economic efficiency of which is undoubted, without compromising the construction and technical properties of cement stone, mortar and concrete.

The cavitation number α characterizes the cavitation intensity, providing its indicated physicochemical effect on the cement-water suspension, on products based on the latter and, accordingly, also on the characteristics of cement stone and materials based on it. As the thixotropic liquefaction of the specified suspension during its preparation at the first mixing stage and a corresponding decrease in its dynamic viscosity η during the cavitation treatment, as follows from the analysis of formula (1), the cavitation number decreases from the indicated maximum, equal to about 3.8 and corresponding according to [33] the minimum degree of manifestation of cavitation cavities, or “initial cavitation”, to a specified minimum of approximately 0.6 · 10 ^-4 , and characterizing, according to [33, 34], a high degree of development of cavitation ion cavities, or “stable cavitation” in the range of cavitation numbers less than 0.35 [35]. The real values of all variables in formula (1), determined on the experimental setup of the authors, and the calculation of the indicated values of the cavitation number in the range of practically possible operating parameters are presented below in examples of the method for producing a cement-water suspension and materials based on it according to the invention. It should be added that formula (1) was derived by the inventors on the basis of dimensional analysis in accordance with the general recommendations [36] as applied to the general case of a plane axisymmetric cavitation flow [37, 38], and then adjusted according to experimental data according to the test results developed by installation. She allowed to construct a device for implementing the method described below, not by trial and error, but according to calculated data, verified experimentally.

Note that a decrease in the cavitation number α in the range from 10 ^-3 to 10 ^-4 leads to an increase in energy consumption during mixing and energy intensity of the centrifugal force field, as well as to an increase in air entrainment into the suspension, therefore, the beneficial effects of the invention at least do not increase. The increase in the values of the specified number to 10 ^-2 and then to 10 ^-1 , corresponding to a decrease in the intensity of cavitation, significantly reduces the beneficial effects of the invention and is impractical. It is allowed only in a short period of time during acceleration of the processing process.

The values of the coefficient k ₁ within 0.55-0.8 and the coefficient k ₂ within 0.5 ± 0.05 are guaranteed by the design of the device for implementing the method described below.

в пределах 0,25-1,25 МПа представляют диапазон доступных давлений, которые достаточны для дезагрегации цемента и удаления воздушных прослоек вокруг его частиц в процессе перемешивания, а также для эффекта самоочищения смесительного устройства при интервале изменений радиуса R в пределах 0,4-1,2 м (оптимальный диапазон). При радиусе менее 0,4 м значение числа кавитации повышается до 5 и выше, что соответствует отсутствию кавитации, при этом значительно сокращается ряд полезных эффектов изобретения. При значениях R более 1,2 м существенно затрудняется сохранение сплошности слоя цементо-водной суспензии, начинается ее смешивание с цементной пылью и налипание на верхней части внутренней поверхности смесителя, что сужает область применения способа. При значении Δ Н менее 0,25 МПа эффект дезагрегации цемента является неполным, а самоочищение смесителя временами отсутствует, что существенно затрудняет промышленное использование изобретения. Условия, создающиеся при Δ Н более 1,25 МПа, примерно аналогичны условиям при R более 1,2 м. Диапазон значений Δ Р в пределах 0,1-0,25 МПа является оптимальным. Снижение этого показателя за пределы приведенного диапазона соответствует затруднениям в инициировании кавитации и снижению полезных эффектов изобретения, а рост сверх приведенного диапазона приводит к последствиям, аналогичным описанным выше при R более 1,2 м. Частота вращения указанного поля может быть выше приведенного диапазона (5-100 с^-1) вплоть до 120-200 с^-1, однако последние значения пригодны преимущественно для случая особо тонкомолотых, или высокодисперсных цементов, преимущественно получаемых из пыли цементных мельниц как в исходном, так и в модифицированном состоянии при их использовании для тампонирования или укрепления сыпучих сред. Частота вращения поля аналогичным образом может быть и ниже указанного диапазона, что допускается в частном случае использования особо грубомолотых цементов для гидротехнических сооружений в целях уменьшения тепловыделения цемента, однако не ниже уровня 2 с^-1, в противном случае исчезают полезные эффекты изобретения.Values

in the range of 0.25-1.25 MPa are the range of available pressures that are sufficient to disaggregate the cement and remove air layers around its particles during mixing, as well as for the self-cleaning effect of the mixing device when the radius R varies within 0.4-1 , 2 m (optimal range). With a radius of less than 0.4 m, the value of the cavitation number rises to 5 and higher, which corresponds to the absence of cavitation, while the number of useful effects of the invention is significantly reduced. With R values of more than 1.2 m, it is significantly difficult to maintain the continuity of the cement-water suspension layer, it begins to mix with cement dust and stick to the upper part of the internal surface of the mixer, which narrows the scope of the method. When Δ H is less than 0.25 MPa, the effect of cement disaggregation is incomplete, and at times the mixer does not self-clean, which significantly complicates the industrial use of the invention. The conditions created when Δ H is more than 1.25 MPa are approximately similar to conditions when R is more than 1.2 m. The range of values of Δ P in the range 0.1-0.25 MPa is optimal. A decrease in this indicator outside the given range corresponds to difficulties in initiating cavitation and reducing the beneficial effects of the invention, and growth in excess of the above range leads to consequences similar to those described above with R over 1.2 m.The rotation frequency of this field may be higher than the above range (5- 100 s ^-1 ) up to 120-200 s ^-1 , however, the latter values are suitable mainly for the case of especially finely ground, or finely dispersed cements, mainly obtained from the dust of cement mills as an outcome Mr., and in a modified state when used for plugging or strengthening bulk media. The rotation frequency of the field can likewise be lower than the specified range, which is allowed in the particular case of using particularly coarse cement for hydraulic structures in order to reduce the heat generation of cement, but not lower than level 2 s ^-1 , otherwise the useful effects of the invention disappear.

In embodiments of the invention, its essence in terms of the method of producing a cement-water suspension and materials based on it is improved using the following additional technological methods:

A. The introduction of filler and aggregates can also be used to activate the specified suspension with cavitation, by which the surface of particles or grains of these materials is cleaned of natural impurities and activated to interact with hydrated neoplasms of cement to a greater extent than is observed with vibrational activation of the surface of the latter. When carrying out the invention, it is characterized by the possibility of increasing the filling capacity of cavitation-activated cement stone obtained on the basis of an activated suspension, and, accordingly, the filling capacity of solutions and concrete obtained on the basis of the latter.

B. Thixotropic dilution of a cement-water suspension. Obviously, an attempt to pump air through a cement paste of normal consistency to bubble it cannot be a positive result due to the high viscosity of the test (more than 2000 Pa · s). It is advisable to use its direct physical characteristic as a liquefaction indicator — the viscosity of the extremely fractured structure, which characterizes the minimum viscosity of a cement-water suspension and products based on it under increasing mechanical stresses [39]. The indicated limits (16-130 Pa · s) correspond to the experimental data for the viscosity of the cement paste of normal density in a shear viscometer at the maximum possible shear rates (0.2-0.3 m / s). Lower (about 10) and higher (up to 300 and higher) Pa · s values of the indicated viscosity are not optimal, since they increase the formation of sprays upon activation and make it difficult to introduce fillers, fillers, and additives during sparging, respectively.

B. Fractional mixing of cement with water, which consists in introducing part of the mixing water not immediately, but in portions, during the mixing of the cement-water suspension according to the method according to the invention under conditions of cement activation, experiments show that it is more effective in comparison with the known technological method of double portion administration mixing water in old works [39, 40], where cement activation with stirring was either not foreseen or was carried out by vibration.

D. Mixing, carried out at the required value of the average specific energy density of the specified field of centrifugal forces (1.8-25 kJ / m ³ ), is necessary and sufficient for the activation of cement by the method according to the invention. The indicated energy intensity limits are established empirically and significantly lower than those observed in the local zones of the cement-water suspension adjacent to the surface of the vibration activator, in particular, the deep vibrator, but in the method according to the invention they cover the entire volume of the processed material. Increased energy stress values are required, as a rule, only in the cases of especially finely ground cements mentioned above. Naturally, they do not prevent the manifestation of the positive technical effects of the invention, but lead to an increase in the required energy consumption.

D. The introduction of functional additives for concrete according to [41] in accordance with the method according to the invention, as provided above, is more effective than the prior art, since it has been experimentally established that, under conditions of cement activation and the presence of a higher content of primary hydration products in said suspension cement, namely, “cement gel”, the optimal dosages of these additives, selected according to the criteria according to [42], should be reduced to 50-70 wt.% of their effective concentration when inactive or vibro ktivirovannom stirring of the prior art [23]. The most effective is the introduction according to the method according to the invention of these additives not with the first portion of mixing water, but separately, in the process of bubbling, when the primary submicrostructure of the cement gel has already developed and the negative effect of many additives either on the structure of hydrates (accelerators, retarders, matting additives), or on the rate of hardening of cement (water-reducing additives, etc.) is reduced. In the same period after the start of sparging, it is most expedient to introduce fillers or fillers with an additional amount of water, since during this period the most effective interaction of the two surfaces activated during processing by intensified cavitation in the field of centrifugal forces — the filler and the aforementioned “cement gel” - is provided.

As for the next generation of cement and concrete additives, called anti-shrink (the term was first introduced in 2002 [43]) and mainly used in the method of producing cement stone and materials based on it according to the invention, they contain:

- as an inorganic base: sulfoaluminate clinker, comprising at least 30 wt.% calcium sulfoaluminate, or aluminum sulfate, and

- a peptizing component whose functions are:

- initiating selective etching of the aluminate phase of the Portland cement clinker after it is mixed with water to isolate the [AlO ₂ ] ^- and [AlO ₄ ] ^5- ions participating in the construction of expanding submicro films of calcium hydrosulfoaluminates around each particle of the clinker component of Portland cement and / or cements based on it , and

- protection of these sub-microfilms from carbon dioxide of the air, fragmenting these sub-microfilms and reducing their expanding and anti-shrink effect.

Accordingly, this component includes two ingredients - an etchant and a film former.

The main advantage of these anti-shrink additives over expanding additives of the previous generation is that the latter must be introduced in order to achieve an expanding effect in cement stone and materials based on it in the amount of 18-20% of the mass of the clinker component of Portland cement [44], and for non-shrinkage of cement stone or materials based on it - at least 6-10% of the mass of cement [45], whereas according to the authors of the invention, the content of anti-shrink additives according to [43] to achieve the expanding effect when applied and the method according to the invention should be a maximum of 3% by weight of the clinker component of Portland cement, mainly 1.5-2 wt.%, and the non-shrinkage of the cement stone and materials based on it, including anti-shrink additive, is already achieved with its content of about 1% by weight of the clinker component of Portland cement that follows from the data given in the example embodiment of the invention. Naturally, such a significant reduction in the consumption of this expensive additive compared to the previous generation of expanding additives provides significant savings and expand the scale of implementation. Moreover, in the method according to the invention, due to the absence of CO ₂ impurities in the medium, the achievement of the same effects is possible at even lower values of the anti-shrink additives according to [43] in the cement-water suspension and products based on it. Thus, the use of anti-shrink additives in the implementation of the method according to the invention also becomes more effective compared with the prior art.

E. The use as a cement in the method according to the invention of the above varieties for enhancing the technical effect of the invention is associated with the functions usual for these varieties, and the special effects of these cements increase when they are used according to the method of the invention in comparison with their effects known from the literature that is described in detail in an example embodiment of the invention.

I. The use of aggregates in materials based on cement stone obtained by the method according to the invention under conditions that substantially reduce the harmful chemical effect of carbon dioxide impurities in hydrated neoplasms of cement on the technical properties of the latter, can radically increase the beneficial effect of using carbonate fillers and aggregates of any mineral type (limestone , marble-like, dolomites) or fillers and aggregates with carbonate impurities obtained by the method according to the invention eniyu materials based on said suspension due to higher strength and durability of these materials, namely, mortar, and concrete. This is achieved by activating cement in a field of centrifugal forces, combined with cavitation. This embodiment of the invention can be effectively used for partial or complete replacement in concrete without changing their technical properties of long-haul granite crushed stone to local carbonate, in particular limestone, which is shown in one embodiment of the invention and may be of great economic importance for a number of regions of the country. In addition, the application of the method according to the invention allows to soften, if necessary, the requirements for the cleanliness and fractional composition of aggregates, in particular, for humus impurities and modulus of sand fineness in mortars and concretes and for the content of fractions active with respect to alkali cement in large aggregate for concrete.

The invention in terms of a method for producing a cement-water suspension becomes clearer from an example of its implementation.

Example 1. To obtain a cement-water suspension and materials based on it - cement stone, mortar and concrete according to the method according to the invention use the following starting materials and equipment:

Source materials:

- as a hydraulic binder, the following cements:

C1: Portland cement ПЦ500 Д0 (grade 500, without mineral additives), including: as a clinker ingredient - Portland cement clinker of the following chemical and mineralogical composition (here and below in wt.%): For major oxides: SiO ₂ 21.80; Al ₂ O ₃ 5.29; Fe ₂ O ₃ 5.09; CaO 65.35; MgO 1.1; SO ₃ 0.38; R ₂ O 0.32; including K ₂ O 0.3 and Na ₂ O 0.12; amount 99.33; silicate module (n) 2.10; alumina module (p) 1.04, lime saturation coefficient (KH) according to V.A. Kind: 0.90; the content of the remaining small components: Li ₂ O≅ 0, BaO 0.07, SrO 0.002, NiO 0.031, CoO 0.02, Mn ₂ O ₃ 0.095, Cr ₂ O ₃ 0.188, MoO 0.054, TiO ₂ 0.02, P ₂ O ₅ 0.19, Cl ₂ 0, F ₂ 0; calculated mineralogical composition (wt.%) of the average clinker sample: alit (C ₃ S) 58, belite (C ₂ S) 19, tricalcium aluminate (C ₃ A) 5.4, calcium aluminoferrite (C ₄ AF) 15.5, impurities - the rest; as a calcium sulfate ingredient, gypsum stone containing two-water gypsum in an amount of 98.6% by weight, impurities - the rest; at wt. ratio of ingredients 100: 5; specific surface area of cement (S, here and below determined by the method of breathability in accordance with [46]) - 310 m / kg;

C2: Portland cement quick-hardening PTs500 D0 BT (grade 500, without mineral additives) based on clinker and calcium sulfate ingredients similar to those used in Ts1, by weight. the ratio of ingredients 100: 5.5 and S 375 m ² / kg;

C3: Portland cement, high-strength PC600 D0 (grade 600, without mineral additives), including Portland cement clinker of the following chemical and mineralogical composition as a clinker ingredient: chemical composition of the main oxides: SiO ₂ 23.94; Al ₂ O ₃ 3.60; Fe ₂ O ₃ 3.44; CaO 67.14; MgO 0.76; SO ₃ 0.34; R ₂ About 0.26; including K ₂ O 0.18 and Na ₂ O 0.14; the amount of 99.48, including p.p. 0.21; n 3.40; p 1.05; KN according to V.A. Kind: 0.89; the content of the remaining small components: Li ₂ O≅ 0, BaO 0.03, SrO≅ 0, NiO 0.01, CoO 0.01, Mn ₂ O ₃ 0.12, Cr ₂ O ₃ 0.15, MoO ₂ 0, 02, TiO ₂ 0.09, P ₂ O ₅ 0.08, Cl ₂ 0.01, F ₂ O, calculated mineralogical composition of the average samples of the control clinker: alit (C ₃ S) 62, belite (C ₂ S) 22, tricalcium aluminate (C ₃ A) 4.0, calcium aluminoferrite (C ₄ AF) 10.0, impurities - the rest; as a calcium sulfate ingredient - gypsum stone, similar to that used in C1, at wt. the ratio of ingredients 100: 6 and S 465 m ² / kg;

C4: slag Portland cement ШПЦ 400 (grade 400) based on clinker and calcium sulphate ingredients similar to those used in C1, including granulated blast furnace slag of the following chemical composition: p.p. 0.36; SiO ₂ 31.75; Al ₂ O ₃ 10.63; Fe ₂ O ₃ 2.12; MnO 0.30; CaO 50.90; MgO 1.24; S (sulfide ion) 2.09; SO ₃ 0.30, impurities - the rest, with a mass ratio of ingredients 60: 6: 40 and S 400 m ² / kg;

C5: sulfate-resistant Portland cement SSPTS 500 D0 (grade 500, without mineral additives), including: as a clinker ingredient - Portland cement clinker of the following mineralogical composition: alite (C ₃ S) 46, belite (C ₂ S) 35, calcium oxide (CaO) free 0.5, tricalcium aluminate (C ₃ A) 4, calcium aluminoferrite (C ₄ AF) 14, impurities - the rest; as a calcium sulfate ingredient - gypsum stone, similar to that used in C1, at wt. the ratio of ingredients 100: 5 and S 380 m ² / kg;

C6: pozzolanic Portland cement (PPC) grade 400, including as a clinker ingredient - Portland cement clinker, similar to that used in C5; as an active mineral additive - flask composition: pp 17,36; SiO ₂ 52.03; Al ₂ O ₃ 6.25; Fe ₂ O ₃ 3.54; CaO 17.31; MgO 1.67; SO ₃ 0.05; Na ₂ O 0.25; To ₂ About 1,54, including water-soluble alumina in an amount of 4% of the mass; as a calcium sulfate ingredient - gypsum stone, similar to that used in C1, at wt. the ratio of ingredients 100: 20: 5 and S 490 m ² / kg;

C7: cement of low water demand according to [47] (D-CNV), grade 1000, with the definition of the latter in accordance with [47], including Portland cement clinker as the Portland cement clinker, similar to that used in C3, as calcium sulphate ingredient, two-water gypsum, similar to that used in C1, as an organic water-reducing modifier — sodium naphthalene sulfonate — cement modifier MTs-1 according to [48], including sodium sulfate up to 2 wt.%, at wt. the ratio of these ingredients 98: 5: 2 and S 640 m ² / kg;

C9: expanding 400 grade Portland cement, including: a mixture of quick-setting Portland cement (C2), expandable gypsum-alumina cement according to [49], containing (wt.h) alumina cement 70 and calcium sulphate ingredient - gypsum stone similar to that used in C1 30, and flask similar to that used in C6, at wt. the ratio of ingredients 85: 25: 15 and S 420 m ² / kg;

C10: non-shrink Portland cement grade 550, including Portland cement (C1) and anti-shrink additive PUD2 with the following characteristics and wt. the ratio of the components of the specified non-shrink Portland cement 100: 1.5 and S 350 m ² / kg;

Ts11: Portland cement ПЦ600 Д0 (grade 600, without mineral additives) based on promoted clinker [50] composition: SiO ₂ 21.90; Al ₂ O ₃ 3.56; Fe ₂ O ₃ 3.43; CaO 68.74; MgO 1.04; SO ₃ 0.42; R ₂ O 0.14; including K ₂ O 0.09 and Na ₂ O 0.08; amount of 99.09; the content of the remaining small components: Li ₂ O O, BaO 0.07, SrO 0, NiO 0.01, CoO 0.03, Mn ₂ O ₃ 0.21, Cr ₂ O ₃ 0.22, MoO ₂ 0.03, TiO ₂ 0.18, P ₂ O ₅ 0.17, Cl ₂ 0, F ₂ O; mineralogical composition in wt.%: C ₃ S 83,0; C ₃ A 3.6; C ₄ AF 10.45, impurities - the rest; according to the petrographic analysis of the average sample, C ₃ S 80, C ₃ A according to the staining method 4, C ₄ AF 10.5, impurities - the rest; sulfate-calcium ingredient - gypsum stone, similar to that used in C1, at wt. the ratio of ingredients 100: 5 and S 380 m ² / kg;

C12: slag Portland cement ШПЩ 500 (grade 500) based on a promoted clinker similar to that used in C11, a calcium sulfate ingredient similar to that used in C1, including granulated blast furnace slag similar to that used in C4, with a mass ratio of ingredients of 60: 6: 40 and S 420 m ² / kg;

Ts13: a mixture of cements Ts1 and Ts8 of brand 750 with the definition of the latter in accordance with [47] with a mass ratio of ingredients of 50: 50 and S 480 m ² / kg;

Ts14: a mixture of cements Ts1 and Ts9, non-shrink Portland cement grade 400 with a mass ratio of ingredients of 50:50 and S 380 m ² / kg;

- as a filler:

material from group I:

HI: silica fume granulated with C-3 superplasticizer (organomineral type MB modifier according to [51];

material from group II:

HII: fly ash of a thermal power plant of the composition: pp 0.79; SiO ₂ 30.45; Al ₂ O ₃ 28.25; Fe ₂ O ₃ 13.01; CaO 3.23; MgO 1.59; Na ₂ O 0.74; K ₂ O 0.15; SO ₃ 0.50; TiO ₂ 1.29; impurities - the rest; S 280 m ² / kg after preliminary grinding;

material from group III:

HIII: ground expanded clay S 300 m ² / kg;

material from group IV:

HIV: Clinker kiln dust composition: pp 34.38; SiO ₂ 10.94; Al ₂ O ₃ 3.36; Fe ₂ O ₃ 3.27; CaO 41.35; MgO 0.55; SO ₃ 0.46; R ₂ O 5.14, including K ₂ O 4.61 and Na ₂ O 2.10; the sum of 99.45, impurities - the rest, S 510 m ² / kg;

- as additives for concrete in accordance with [41], also called chemical additives [14, 20, 39]:

Group I additives - plasticizing, or water-reducing:

IA: sodium polymethylene polynaphthalene sulfonates (C-3) according to [53];

IB: technical lignosulfonates (LST) according to [54];

group II additives - water retention, or improving pumpability:

IIA: carboxymethyl cellulose according to [41];

IIB: polyoxyethylene according to [41];

Group III additives - retarders:

IIIA: molasses according to [41];

IIIB: orthophosphoric acid according to [55];

Group IV additives - additives - setting and hardening accelerators:

IVA: calcium chloride, almost anhydrous (98%) according to [56];

IVB: hexavod aluminum chloride according to [57];

IVB: anhydrous sodium sulfate - calcined, prepared from a technical product according to [58];

IVG: a mixture of additives IVA and IVB in wt. 1: 1 ratio;

group V additives - clogging pores:

VA: anhydrous aluminum sulfate obtained by calcining a technical product according to [59];

VB: iron sulfate according to [60];

Group VI additives - gas-forming:

VIA: aluminum powder according to [61];

VLB: hydrogen peroxide - aqueous solution according to [62];

Group VII additives - air entraining:

VIIA: saponified wood resin according to [63] in the form of a 50% aqueous solution;

VIIB neutralized air-entraining resin according to [64] in the form of a 40% aqueous solution;

Group VIII additives - antifrosty:

VIIIA — sodium nitrite according to [41];

VIIIE — nitrite-nitrate-calcium chloride according to [41];

Group IX additives - hydrophobic:

IXA: a solution of high molecular weight fatty acids (C ₁₈ ) in mineral oil (LHF) according to [65]:

IHB: polyhydrosiloxane - liquid 136-41 according to [66];

- as anti-shrink additives (PUD):

based on aluminum sulfate:

PUD1: a mixture of aluminum sulfate four-water and peptizing component in wt. a ratio of 100: 12, the latter comprising an etchant — mannuronic acid and a film former — calcium stearate in wt. 1: 1 ratio (all ingredients are chemicals);

based on sulfoaluminate clinker:

PUD2: a mixture of sulfoaluminate clinker and a peptizing component in wt. a ratio of 100: 5, the first (technical according to [67]) includes (in wt.%): calcium sulfoaluminate (4СаО · 3Аl ₂ О ₃ · SO ₃ ) 35, white (2СаО · SiO ₂ ) 20, mayenite (12СаО 7Al ₂ O ₃ ) 3,5, calcium monoaluminate (CaO · Al ₂ O ₃ ) 15, calcium ferrites (2CaO · Fe ₂ O ₃ , CaO · Fe ₂ O ₃ ) 5, calcium sulfate (CaSO ₄ ) 15, aluminates and alkali metal ferrites [R (Al, Fe) O ₂ ] 1.5, calcium oxide (CaO) 5, and the second includes (in wt.%): mannitol alcohol 75; calcium stearate 25 (the last two ingredients are chemicals);

PUDZ - an analogue of PUD1, with wt. the ratio of aluminum sulfate and peptizing component 100: 0.8; in the last wt. the ratio of mannuronic acid and calcium stearate 5: 3;

PUD4 - an analogue of PUD1, with wt. the ratio of aluminum sulfate and peptizing component 100: 35; in the last wt. the ratio of mannuronic acid and calcium stearate 1: 0.75;

- as placeholders:

from group I - aggregates of natural (natural) origin:

MZIA: fine aggregate - monofraction quartz sand according to [68];

MZIB: fine aggregate - quartz multifractional sand according to [68];

MZIB: fine aggregate - silica sand of a fraction of 1-5 mm, containing, in wt.%: Quartz 97, feldspars 2, dark-colored minerals - epidote and other impurities 1, with a voidness of 38% by volume; meets the requirements of [69];

KZIA: coarse aggregate - crushed stone of a granite fraction of 5-20 mm, containing, in wt.%: Granite 95, quartzite 3, mica and other impurities 2, with a voidness of 42% by volume; meets the requirements of [70];

KZIB: coarse aggregate - crushed stone of lime fraction 5-15 mm, containing, in wt.%: Calcite 93, feldspar 3, dolomite 2, sandstone and other impurities 2, with a voidness of 45% by volume; meets the requirements of [70];

from group II - aggregates of artificial origin:

KZIIA: perlite crushed stone according to [71];

KZIIB: foam foam - foamed autoclave or non-autoclave materials containing fragments and / or powders of gas silicate or foam silicate or aerated concrete or foam concrete according to [45]; in this example, pieces of foam concrete with a density of D500. strength at the time of use of 1.5 MPa, a fraction of size 3-10 mm, separated on sieves of boundary dimensions;

- as drinking water cement-slurry, mortar and concrete mixtures using drinking water tap water that meets the requirements [72].

For grinding and milling of cements and fillers, as well as powdery additives for concrete in laboratory conditions, an MBL-1 mill with a diameter × length (m) (⌀ × L) of 0.5 × 0.56 is used, two-chamber, of periodic action, lined with cast iron armored plates, with the dimensions of each chamber: length 0.28 m, diameter 0.5 m, rotation speed 48 min ^-1 , drive power 1.1 kW, engine speed 930 min ^-1 , grinding load on 1 chamber (with 10 kg of material) into each chamber): balls ⌀ 60 mm approx. 6 kg, ⌀ 50 mm approx. 8 kg, ⌀ 40 mm approx. 8 kg, ⌀ 30 mm approx. 8 kg, tsilpebs ⌀ 20 mm × L 32 mm 25 kg, total 55 kg. Before weighing, the material to be ground is crushed to a fraction of 1-2 mm in a laboratory jaw crusher.

When implementing the method according to the invention, the strength characteristics of samples of hardened cement-water suspension are determined in samples of cement stone without additives, from cement stone with filler, from cement-sand standard solutions obtained by introducing standard sand into the cement-water suspension obtained according to the invention , as well as from concretes obtained by introducing fine and coarse aggregates into the specified suspension in an additional forced-action laboratory concrete mixer. From a cement-water suspension without additives, as well as with additives and fillers, molded and compacted on a vibrating platform with an oscillation frequency of 50 Hz and mechanical fastening of the molds, cubes 1.41 × 1.41 × 1.41 cm, from a cement-water suspension with additionally introduced standard sand according to [73] is used to form beam samples, or prisms 4 × 4 × 16 cm in size. These cubic and prismatic samples are stored for 24 hours in air-humid conditions - in air at a temperature of 20 ± 3 ° С and 100 % relative humidity, then placed in water of the same temperature and stored to the test point. Sample cubes with a 10 cm rib are made from a cement-water suspension with additional fine and coarse aggregates added and stored under the above-mentioned air-wet conditions. All samples are tested after 3 and 28 days of normal hardening, and in some cases they are subjected to heat-moisture treatment (TVO), the mode of which is indicated in the tables of experimental data, and they are tested 4 hours after the end of TVO and 28 days after their storage in air-wet conditions .

During the first days of storage in natural or air-humid conditions, to prevent evaporation of moisture from the surface of the samples, the mold is covered with a cloth made of coarse canvas moistened with water. To test the samples, a standard hydraulic press with a self-aligning top plate is used. The test results of the sample cubes with an edge of 10 cm lead to the standard size of the samples 15 × 15 × 15 cm by multiplying the maximum value of the compressive strength of the samples obtained in the press by a standard factor of 0.85.

The order of carrying out the invention in this example is described in the description section related to the device for the existence of the described method.

If it is necessary to use fillers and chemical additives, they are usually introduced during bubbling, with the exception of silica fume, which is introduced before bubbling; these additives are also introduced with mixing water or during the introduction of cement into the mixer.

The introduction of fine aggregate in obtained by the method according to the invention cement-aqueous suspension is carried out at wt. ratio (cement): (fine aggregate) at least 1: 1. This ensures the viscosity of the cement-water suspension with an aggregate of not more than 1770 Pa · s; at higher viscosities, cavitation ceases when other parameters are acceptable for the stability of the mixing process, and the effect of the invention is reduced.

An analysis of electron microscopy data of the samples of the obtained suspension indicates that the minimum cement hydration indicated above (2.5 wt.% According to the criterion of loss on ignition — ppt) at the end of the treatment corresponds to the presence of hydrated shells on virtually all cement particles , both large and the smallest. This is the lower threshold necessary under the conditions of activation, which characterizes the achievement of a random distribution of water over the surface of cement particles, namely the Poisson distribution, which ensures the Shestoperov effect and the achievement of positive results when implementing the invention in comparison with the prior art. In the absence of activation, when there is insufficient averaging of hydrates, to achieve a similar result, a much higher level of initial cement hydration is required: at k ₁ about 0.3, corresponding to mixing the components of a cement-water suspension known from the prior art [1], the required degree of hydration cement, as follows from the results of electron microscopy, is approximately 8-10%, which is achievable only after 12 hours of hardening, i.e. cannot be provided with stirring without activation. When using high-activity or low-aluminate cements, in which the initial hydrates contain more portlandite than in ordinary Portland cement, the situation is more favorable compared to the above. In cements with mineral additives, in particular, slag Portland cement and pozzolan cement, hydrate neoplasms are less than in Portland cement, and the decrease is approximately proportional to the content of the corresponding mineral additive (slag, natural pozzolana), the situation, on the contrary, is less favorable, and therefore the required degree of hydration clinker component increases, requiring an increased specific surface area of said cement (400 ^m2 / kg) compared with ordinary Portland cement to solve the problem of the invention (not less than 300-320 m ² / kg).

The resulting cement-water slurry, in particular cement paste, can also be mixed with ready-made dry building mixes available on the market in order to increase their strength and speed of their hardening, usually insufficient for normal use.

The main applications of the activated cement-water slurry according to the invention, as already mentioned, as an injection solution for strengthening foundations and foundations, for filling injection piles, reinforcing screeds, leveling and insulating putties, putties, and, in addition, as a component of conventional mortar and concrete after adding aggregates and water to the suspension. In this example, the cement-water suspension obtained according to the invention is placed in molds for the manufacture of cement stone, and after the introduction of aggregates and an additional amount of water (the latter, if necessary), the resulting mortar and concrete mixtures are placed in molds and cured in air wet conditions to assess the technical properties of the resulting mortars and concrete and compare them with known from the prior art.

The test results of materials prepared in a number of series of experiments in the implementation of the method for producing a cement-water suspension according to the invention, preparation of mortar and concrete mixtures based on it, as well as cement stone, mortar and concrete obtained during their hardening, are presented in tables 1 and 2.

The compositions of the cement-water suspension obtained according to the invention, the compositions of mortar and concrete mixtures made on their basis, used in the experiments, as well as the values of the cavitation number characterizing activation when they are mixed, are shown in table 1. It should be noted that an increase in the number of cavitation means a decrease the intensity of cavitation effects on the cement-water suspension.

The test results of samples obtained by hardening the specified suspension and products based on it, the test results of similar materials obtained according to the prototype, as well as according to the technology known from the prior art, with the addition of such parameters of their manufacture that allow you to calculate the number of cavitation with stirring by the method according to the invention are shown in table 2.

An analysis of the data presented allows us to conclude the following.

1. Products obtained on the basis of a cement-water slurry made by the method according to the invention, namely cement stone, mortar and concrete, are characterized by higher strength at 28 days of age, at 3 days of age (ie, higher speed increase in strength), as well as reduced shrinkage compared to similar products obtained by the method according to the prototype and known from the prior art. This follows, in particular, from a comparison of the data given in table 2, in lines 1-3 (known from the prior art), 4-6 (obtained according to the prototype) and in lines 7 and 31 (according to the invention).

2. A comparison of the data in rows 7-29 of table 2 among themselves indicates that: a) cements of various types in the composition of the specified suspension behave in accordance with their properties known from the prior art, and the cement of low water demand is activated more effectively than others; b) a similar behavior is typical for fillers and additives. From this it can be seen that activation by the method according to the invention does not change the comparative evaluation of cements, fillers and additives between each other and does not change their functional purpose.

3. The activation of the cement-water slurry according to the invention as a whole increases the strength characteristics of materials by about 5-10 MPa, i.e. in some cases - by brand or class; a greater effect is characteristic mainly for cement of low water demand.

4. The activation of the cement-water slurry according to the invention makes it possible to replace in the concrete obtained on the basis of said slurry a part of the granite aggregate with lime without loss of strength (cf. lines 31 and 32 in table 2), moreover, with an increase in the sand content in concrete (see line 33 in the same table).

5. The activation mode, adopted in table 1 as a basis, is actually the most applicable. Its advantages are the stable operation of the equipment, the relatively high quality of the materials obtained with its use, which follows from the data presented in rows 7-29 of table 2. To this it should be added that the coefficient of variation in strength at 28 days of age is 2-3% fewer products based on cement-water suspension according to the invention (lines 11-25, 27, 30-34) compared with products of the prototype (lines 5 and 6) and with products known from the prior art (lines 2 and 3, all - table 2). This, as you know, increases the reliability of materials obtained using the method according to the invention and their competitiveness, and, in addition, increases the prospects of the method for widespread implementation.

Other activation modes, in particular, associated with a more significant increase or decrease in the number of cavitation φ caused by changes in the parameters of the field of centrifugal forces and blowing with compressed air during processing of this suspension, compared with the mode presented in the form of a range of activation numbers in table 1, as follows from the data in table 2 (lines 42-44), do not lead to a radical change in the quality of the materials obtained, although at least one of these modes with a reduced cavitation number (line 43) gives somewhat better e results in comparison with the analog mode (line 7). It should be noted that changes in the activation parameters within the limits set forth in the text of the description of formula (1) increase the quality of materials mainly in combinations leading to a decrease in the number of activation. If you go beyond the mentioned limits, if it is technically feasible, the effect of the invention is not guaranteed, since the method may turn out to be low-tech. And the stability of the regime within the mentioned limits is guaranteed by the experience of the stable operation of the corresponding equipment, which ensures the manufacturability of activation and is one of the main advantages of the method according to the invention.

Regarding the features of the technological activation mode according to the method according to the invention, it should be noted that the changes Δ P and Δ H are mutually compensated, which follows from the data presented in lines 42-44 of table 2; this also applies to the frequency and radius of the field of centrifugal forces. When assigning processing parameters, it should be borne in mind that the high density of the suspension itself increases the effect of cavitation, therefore, the intensity of exposure to such a suspension paradoxically does not need to be increased.

It should also be noted that the data relating to the suspension obtained by the method according to the invention on the basis of the starting components mentioned in the description, but not listed in the tables, allow us to conclude that the effect of the invention is achievable approximately equally when using them. Particular mention should be made of marketed dry mixes available on the market and usually characterized by a low or insufficient binder content. The use of such mixtures as fillers for the suspension according to the invention, which corresponds to an increase in the content of cement in them before being put into use, can significantly increase their technical effect. An improvement in comparison with the prior art for use in concretes and mortars based on this suspension by the method according to the invention of fine sands, including silted sand, which has recently spread widely in rivers with a flow regulated almost to a stop, such as the Volga, is also important. sand dunes containing up to 30 wt.%, sometimes more, of the loess fraction. In some regions of the country, other sands are difficult to access. It is for such places that the fact that on these fine, contaminated sands, the method according to the invention allows to obtain mortars and concrete that meets all the requirements of the standards.

In general, the data obtained indicate that the method of obtaining a cement-water slurry and materials based on it - cement stone, mortar and concrete as a whole allows to significantly improve their construction and technical properties and reduce the coefficient of variation in comparison with both the prototype and prior art.

Thus, the first objective of the invention is the creation of a method for producing a cement-water suspension, significantly exceeding in their properties the characteristics of similar materials known from the prior art, in particular, their strength and uniformity - achieved. The above characteristics make it possible to use the method according to the invention as very effective, but in order to increase the homogeneity and, accordingly, the quality of these materials, it is advisable, moreover, the implementation of the specified method in the corresponding device, providing the proper conditions for the preparation of these materials.

The problem of mixing cement with water and aggregates was solved during the 19th and 20th centuries using various mixers, among which the most productive was the so-called gravitational type mixer, which is a cylindrical body with bandages supported on roller bearings, driven into rotation by a ring gear, with an internal chamber equipped around the perimeter with blades located on helical lines (Frederick Ransom, England, 1885). Although this mixer, in the variant with the conical ends of the cylinder mounted on the chassis, is still widely used, the uniformity of mixing of these initial components leaves much to be desired, since the coefficient of variation in the quality of the mixture is 15%.

More effective mixing devices are known from the prior art, which are apparatuses with agitators consisting of a housing, a drive shaft and an agitator mounted on the shaft, placed in a working chamber located inside the housing, where the initial components of the mixtures are loaded [76]. The numerous variants of mixers for all branches of technology described in the cited work are usually not suitable for mixtures with high cohesion to the walls of the body, which increases as the mixtures approach homogeneity and during the mixing process, which is typical for a cement-water suspension as it approaching the start of setting. Dilution of cement with fillers, and suspension in general with fillers, reduces the specific value of the cohesive force, that is, the force per unit surface of the mixer body, and reduces its rate of increase over time, however, the kinetics of its change remains the same and requires special design changes in the mixer.

In the building materials industry, various devices are known for the preparation of concrete and mortar mixtures, including cement-water suspensions. Known devices, usually made in the form of high-speed mixers for this purpose, as a rule, have vertical one- or two-support drive shafts on which rotary working bodies with mixing blades are mounted [77].

These mixing devices are designed for one-stage production of these materials and cannot be used to activate cement in the composition of a cement-water suspension. In addition, their operation is quite laborious with a limited resource of work.

The closest analogue of the present invention (prototype) in technical essence and the achieved result is a device made in the form of a mixer for producing a cement-water suspension containing a stirrer placed in a cylindrical chamber, including an open turbine rotor with radial-arc vanes on a disk facing the bottom mixer chamber and cantilever mounted on a vertical shaft located in the Central hole of the bottom with an annular gap, as well as containing a lower drive shaft, a hatch for feeding and similar components and discharge nozzle with shutter [78].

Its main disadvantage is unsuitability for cement-water suspension undiluted with aggregate. The working chamber of this mixer quickly overgrows with the products of initial cement hydration and the mixing product cannot be completely unloaded from the working chamber, and cleaning the latter significantly reduces the performance of the mixer, increases the proportion of manual labor and the cost of servicing the apparatus. In addition, the shaft of this mixer cannot be isolated from penetration through the leaks of the liquid phase of the suspension, which for a short time will necessitate its replacement and, therefore, frequent repairs. These features led to the lack of widespread implementation of this technical solution in the construction industry and the construction industry as a whole, even as a mixer for more mortar-tolerant mortars. It should be especially noted that to date in the mentioned branches of technology there are no stable working mixers for concentrated cement-water suspensions with W / C in the range 0.22-0.6. That is why such suspensions, which are needed in many areas of construction, are still used only in laboratory conditions.

The objective of the invention in terms of the mixer is to provide in the last physico-mechanical activation of cement, as well as improving the stability of the equipment.

The problem is solved in that in a device made in the form of a mixer for producing a cement-water suspension containing a stirrer located in a cylindrical chamber, including an open turbine rotor with a radial arc and vanes on a disk facing the bottom of the mixer chamber and cantilever mounted on a vertical a shaft located in the Central hole of the bottom with an annular gap, and also containing a lower drive shaft, a hatch for supplying the source components and a discharge pipe with a shutter, the bottom of the chamber is equipped with grease a box with a seal for the shaft, the cavity of which is made in communication with the working space of the chamber by means of an annular gap, while the ratio of the cross-sectional areas in the light of the chamber and the annular gap is 1100-325000, the stuffing box is equipped with a fitting for supplying compressed air to its cavity, and the discharge the pipe is tangentially connected to the camera.

In an embodiment of the invention, the hatch is equipped with a loading nozzle made in the form of a return cone located in the chamber coaxially with the mixer, while the lower edge of the cone is spaced from the upper edge of the chamber at a distance equal to 1 / 3-1 / 2 of the height of the latter.

The essence of the invention in terms of the device consists in the fact that the specified mixer for the first time provides the mixing of a cement-water suspension under production conditions due to the significant effect of the intensified injection of cavitation, combined with the mixing of the processed material in a turbine mixer. The blowing, in addition, not only prevents the suspension from penetrating into the crankcase and the interruption in operation associated with this, and subsequently the mixer failure, but also eliminates the vacuum in the cavitation cavities of the suspensions. The pump effect of the mixer, the completeness of processing the suspension in the entire volume of the mixer chamber and the increased gel content in the modified blowing phase composition of the products of the initial interaction of cement with water prevent the last walls of the mixer chamber from fouling, ensure that it is unloaded after each kneading, equal to 100%, and the speed of the unloading process suspension, in its duration not exceeding 5-20 s, and more often - 5 s. All these features of the mixer represent the main set of features of its novelty.

Another sign of the novelty of the mixer relates to the ratio of the cross-sectional areas of its cylindrical working chamber and the area of said annular gap between the shaft and the hole in the bottom of the working chamber used for blowing. The indicated limits of the ratio are due to the following considerations tested on semi-production mixers.

The initial data is as follows:

- gap sizes: from 0.05 cm to 0.5 cm; then with a shaft diameter of 1 cm, the area s _{0 of the} annular cross-section of the gap can be taken to be approximately equal to 0.25 cm ² to 2.5 cm ² ;

- the maximum radius of the mixer chamber 1.6 m = 160 cm (more than the optimum adopted in the notation of formula (1) mentioned above and equal to 1.2 m), which corresponds to the circle cross-sectional area of the chamber S ₀ 80384 cm ² ;

- the average diameter of the droplets of water fog formed in the mixer by blowing, 1 μm; this approximately corresponds to the average droplet size in industrial fogs, the nuclei of which are non-settling dust, the size of which in the composition of cement is in the range from 0.3 to 2 microns [78];

- air viscosity ν = 18.11 · 10 ^-6 / dm ³ at 20 ° C;

- air density γ ₀ = 1.3 g / dm ³ at 20 ° C;

- water density γ = 1000 g / dm ³ at 20 ° C;

- air flow rate for blowing 0.06 m ³ / min = 60,000 cm ³ / min = 1000 cm ³ / s;

We determine the air velocity in the gap section by the formula:

w = v / s ₀ = 1000: 0.25 = 4000 cm / s (maximum) or 1000: 2.5 = 400 cm / s;

these values correspond to blowing only 0.1 l of air for each revolution of the mixer.

We write the formula of the Fedorov criterion for the direct-flow joint flow of air and droplets of fog over the stirred suspension and calculate its value:

The value of the Reynolds criterion for the specified flow is:

The value of the rate of droplet dropping in the indicated flow is calculated by the formula

where from

w _in = 7.97 · 10 ^-3 · 18.1 · 10 ^-6 / (1 · 10 ^-6 ) = 0.144 m / s = 14.4 cm / s.

The speed of the blown air in section S _{o of the} working chamber of the mixer at the indicated flow rate should be lower than the rate of droplet dropping. It amounts to 1.6 and 0.3 m for the maximum and minimum radii of the chamber:

v _pк1 = v / S ₀ = v / (π R _max ² ) = 1000/80384 = 0.012 cm / s;

v _pk2 = v / S ₀ = v / (π R _min ² ) = 1000/2826 = 0.35 cm / s.

In addition to the soaring speed according to formula (2), it is necessary to additionally take into account the air velocity component associated with the acceleration due to the collapse of the cavitation cavities that open in the upper outer layer of the stirred suspension and the accelerated release of air from them, since air is not drawn into the cavity formed in this layer, and comes from blowing. The additional component is taken in the form of a proportionality coefficient K _k , the reciprocal of the cavitation number, with the correction k ₂ = 0.5 from formula (1). In addition, it should be noted that the instantaneous horizontal cross-sectional area of collapsing caverns on the surface of the suspension layer is substantially - approximately 100 times - less than the total cross-sectional area of the working chamber, and the corresponding correction k ₃ according to experimental data is 0.01. Therefore, to estimate the critical velocity v _k of the spray movement, a relation based on formula (1) is used:

In this case, as an estimate for φ, take at R _max = 1.6 m the value from row 43 of table 3 φ ₁ = 0.84 · 10 ^-3 ; when R _min = 0.3 m - the average value of the values taken from column 10 of table 1, equal to φ ₂ = 2.14. Then by the formula (3) we obtain respectively:

v _k1 = v _pk1 · (k ₂ k ₃ / φ ₁ ) = 0.012 · 0.5 · 0.01 / (0.84 · 10 ⁻³ ) = 0.071 m / s = 7.1 cm / s;

v _k2 = v _pk2 · (k ₂ k ₃ / φ ₂ ) = 0.35 · 0.5 · 0.01 / (2.14 · 10 ^-3 ) = 0.818 m / s = 81.8 cm / s.

It is for the latter option — with a minimum radius of the body — that a spray cut-off in the form of a reverse cone located in the chamber coaxially with the mixer is required, while the lower edge of the cone is separated from the upper edge of the chamber by a distance equal to 1 / 3-1 / 2 of the height of the latter, so that allow at least part of the spray to evaporate in flight. Usually, all modifications of the mixer are supplied with such a cutter as a guarantee against splashes at a higher rotational speed n compared to the optimal limits given above, in order to mix cement-water suspensions in cases where cement with an especially high specific surface is used - above 1000 m ² / kg by the method of breathability, or above 500 m ² / kg by the method of low-temperature nitrogen adsorption according to Brunauer-Emmett-Teller (BET). In addition, the cone forms the return flow of the suspension from the outer layer, formed by the centrifugal force of the mixer, to the central part of the latter, in the presence of a fine aggregate in the suspension, enhancing the inertial component. In this case, less spray is formed, and for the formation of said return flow, the distance between the upper edge of the chamber and the lower edge of the cone is set within 1 / 3-1 / 2 of the height of the chamber.

The foregoing indicates that the actual ratio A between the value of S ₀ , varying from 0.25 cm ² to 2.5 cm ² , and the value of S ₀ , varying from 2826 cm ² to 80384 cm ² , which guarantees the absence of splashes, is ranging from 2826 / 2.5 = 1130 to 80384 / 0.25 = 321536, or from about 1100 to 325000.

Maximum A is limited by reducing the cavitation number to a minimum of φ = 0.6 · 10 ^-4 , below which a rapid increase in air content in the cement-water suspension begins, which reduces the effect of the invention. So, with φ = 0.5 · 10 ^-4 , achieved in trial mode on a mixer with R = 1.6 m and n = 250 s ^-1 (15000 rpm), with Δ Н = 0.75 MPa, Δ P = 100 KPa, η = 60 Pa · s, with a threat to the stable operation of the mixer for mechanical reasons, the useful technical effects of the invention are reduced due to a decrease in ρ to 1850 kg / m ³ due to increased air entrainment.

In general, in the range of values A between 1100 and 325000, the experiments performed by the authors on models of mixers allow us to conclude about their stable operation, the completeness of unloading of the treated cement-water suspension, corresponding to 100%, and the unloading time for 5-15 s.

The invention in terms of the specified device in connection with the characteristics of the cement-water suspension and products based on it, obtained by the method according to the invention using the device for implementing this method, becomes clearer from the above drawing (figures 1 and 2).

Figure 1 schematically shows a mixer for producing a cement-water suspension and products based on it, side view; figure 2 is a top view, a section along aa in figure 1.

The mixer comprises a cylindrical chamber 1, a mixer 2, made in the form of a rotor of an open turbine with radial-arc blades 3, mounted on a disk 4, facing the bottom 5 of the chamber. The disk is cantilever connected to a vertical shaft 6 having a lower drive 7. The shaft is located in the central hole of the bottom with an annular gap 8, while the ratio of the cross-sectional areas in the light of the chamber and the annular gap is 1100-325000. On the outside, the bottom is equipped with a stuffing box 9 with a seal 10 for shaft 6. The cavity of the box 9 communicates with the working space of the chamber through an annular gap 8. In this case, a fitting 11 is provided in the box for supplying compressed air to its cavity and then into the chamber through the annular gap.

The hatch 12 of the cylindrical chamber is equipped with a loading pipe 13, made in the form of an inverse cone. The latter is installed in the chamber coaxially with the mixer, and its lower edge is separated from the upper edge of the chamber at a distance equal to 1 / 3-1 / 2 of the height of the latter.

The discharge pipe 14 having a shutter 15 is connected to the chamber tangentially to the circumference of its bottom.

The order of the mixer is as follows.

The discharge pipe 14 is closed by a shutter 15. From the compressor (not shown), a nozzle 11 is supplied with air at a pressure 11 sufficient to prevent leakage of the cement-water suspension from the chamber through the annular gap into the cavity of the stuffing box. Then the drive 7 is turned on and the agitator 2 is rotated. Through the inlet pipe 13, the dosage components of the suspension — water and cement — are fed into the chamber 1. To carry out sparging, the pressure of the air supplied to the chamber is increased until air bubbles appear on the surface of the stirred cement-water suspension, observed through a window 16 in the upper part of the chamber.

When a turbine with blades rotates, the suspension is discarded under the action of centrifugal forces to the chamber wall, moves upward along it and then under the action of gravity and due to the increased inertial component of the mass in the presence of a filler and the geometric shape of the chamber working space formed by the top cover 17 and the conical surface of the loading nozzle 13, without reducing speed and in the absence of discontinuities in the circulating stream, it is directed to the rotating rotor, directly into the zone of its action. The nature of the effect on the suspension of the rotor of the mixer is similar to the nature of the effect of the wheel of a centrifugal pump.

The finished cement-water suspension through the discharge pipe 14 with the open shutter 15 and the rotating rotor is discharged from the mixer. Centrifugal swirling of the flow of the finished suspension and the tangential location of the discharge pipe on the camera determines the self-cleaning of the working surfaces of the camera and the discharge pipe.

The foregoing allows us to conclude that the second objective of the invention is the creation of a mixer for the rational production of a cement-water suspension with cavitation activation - achieved.

The invention for the first time allows you to activate a cement-water suspension with an increase, regardless of the quality of the cement, of the strength of the hardened products based on it by 12-15% with a parallel decrease in their shrinkage deformations and coefficient of variation of properties by 2-3% at 100% fullness of cement discharge -aqueous suspension after each batch and unloading time of not more than 15 s, ensuring the manufacturability of the method, the performance of the mixer in cement-water suspension up to 120 m ³ / h without any manual labor, as well as substantial to substantially improve the structure of the volume and surface of the materials obtained.

Thus, the method of producing a cement-water suspension and a mixer for its implementation have fundamental advantages compared to those known from the prior art, characterized by novelty elements and being multivariate technical solutions that do not require tight binding to specific suppliers of the initial components of this suspension and to specific engineering enterprises, which is essential to ensure the minimum cost of both the specified suspension and the mixer for its production in a market economy ohmiki. Thus, these technical solutions are prepared for widespread production implementation.

Sources of information

1. Sovalov I.G. et al. Cement activation methods and the effect of activation on the properties of concrete. M.: CBTI NIIOMTP, 1963, 41 p.

2. Skramtaev B.G. and others. Improving the strength of cement and concrete by adding gypsum and wet mashing cement. / Building materials, 1951, No. 8.

3. Fishchuk M.A. Study of the effectiveness of the use of wet cement milling in the manufacture of prestressed concrete beams of bridge spans. Abstract. diss. for a job. student step. Cand. tech. sciences. M .: NIIZHB, 1953. 20 p.

4. Rudnev N.G. The use of vibration grinding to activate standard cement. / Proceedings of the Research Institute of Railway Construction, issue IX. M .: Transzheldorizdat, 1951.

5. Kevesh P.D. et al. Vibratory dominance of cement in the aquatic environment. M .: Bureau of those. assistance of the Research Institute of Gorselstroy, 1955, 8 pp.

6. Proceedings of the meeting on the vibratory grinding of cement. Ed. M.I. Gershman and others M.: Promstroyizdat, 1957.

7. Gorchakov G.I. and others. Acceleration of cement hardening processes by fine grinding in a vibratory mill. / Vibratory grinding of materials. Scientific communication VNIITISM No. 7. M., 1955.

8. Guildenberg Z.G. and others. Instructions for the activation of cement in factories of reinforced concrete products by milling in vibratory mills (IL 5-56). M .: Promstroyizdat, 1957, 33 pp.

9. Barta R. Chemie a techologie cementu. Praha, Nakl. CAV, 1961, 1107 s., Wiz. s. 655-656.

10. Moshchansky N.A. Mechanical activation of cements. / Construction industry, 1951, No. 8.

11. Listopadov M.E. Hydraulic activation of binders. / Building materials, 1960, No. 3.

12. Adamovich A.N. Cementation of the foundations of hydraulic structures. M .: Energy, 1964. See section. on the method of high-speed turbulent activation of injection solutions for cementation work.

13. Uriev N. B. et al. Colloidal cement glue and its use in construction. M.: Stroyizdat, 1967.175 p., See p. 57 and below.

14. Sovalov I.G. Research, development and implementation of effective methods for the construction of reinforced concrete and concrete structures. The report, compiled on the basis of a synthesis of completed and published works, the results of research and implementation in production and submitted for the competition account. Step of Dr. Tech. sciences. M .: TsNIIEP-dwellings, 1968.127s.

15. Staerman Yu.Ya. Vibroactivation of cement. Tbilisi: “Technique and Shroma,” 1957. 44 p. See also: Staerman J. Vibroactivated concrete. Tbilisi: “Sabchota Sakartvelo”, 1963. 181 p. Shtaerman Yu.Ya. and others. Dense concrete on multifraction aggregate. Tbilisi: Ibid., 1967. 212 p.

16. Yusufov I. - M. B. Investigation of the properties of colloidal mortar and concrete: the technology of their manufacture using the AzPI mixing plant. Abstract. diss. student step. Cand. tech. sciences. Baku: Azerbaijan. Polytechnic Institute, 1963.27 p.

17. Skramtaev B.G. Vibro-mixing of concrete mix. / Bulletin of the works of the Military Engineering Academy. V.V. Kuybysheva, Moscow: Military Publishing House, 1959.

18. Desov A.E. Vibro-mixing of concrete mix in a concrete mixer with vibrating blades / Automation and improvement of the processes of preparation, laying and compaction of concrete mixtures. Sat articles. M .: Gosstroyizdat, 1960. See also Kublin I.Ya. Vibroactivation of cement paste with the addition of surfactants and micro-fillers. In the same place.

19. Faitelson L.A. Vibro-mixing of concrete. Abstract. diss. for a job. student step. Cand. tech. sciences. M .: NIIZHB, 1961, 17 p.

20. Kunnos G. Ya. Et al. Theory and practice of vibration mixing of concrete mixtures. Acad. Sciences Latvia. SSR., Riga, 1962.216 s.

21. Higherovich M. I. et al. Effect of surface-active additives on the properties of cement stone. M .: Promstroyizdat, 1954. 72 p.

22. Malinin Yu.S. and others. On the morphological foundations of the structure of cement stone. Doklady AN SSSR, 1977, v. 233, No. 4, pp. 653-656.

23. Mikhailov N.V. The basic principles of the new technology of concrete and reinforced concrete. M .: Gosstroyizdat, 1961.53 pp. (Prototype of the method).

24. Kravchenko I.V. and others. High-strength and especially quick-hardening Portland cement. M .: Stroyizdat, 1971, 228 p., See chap. IV.

25. Shestoperov S.V. Durability of concrete. - M .: Avtotransizdat, 1960 .-- 512s.

26. Rosenthal N.K. Concrete corrosion problems. // 1st All-Russian Conference on Concrete and Reinforced Concrete. “Concrete at the turn of the 3rd millennium. In 3 books, M .: "Gothic", 2001, Prince. 3, section reports, pp. 1419-1430.

27. Zakharov B.N. et al. Study of the parameters of double-frequency vibro-mixing of sand concrete. / Reports of the Interuniversity scientific conference and integrated mechanization and automation in construction. Saratov. Ed. Cap. DNTI, 1960.

28. Sanitary Norms 2.2.4 / 2.1.8.583-96. Industrial vibration, vibration in the premises of residential and public buildings. M .: Ministry of Health of the Russian Federation, 1996.

29. Gurland I. Transactions of Metallurgical Soc. Of AIME, 1958, v. 212, pp. 452-463. In “Plansee Proceedings,” London, Pergamon Press, 1961, pp. 507-514. Transactions of Metallurgical Soc. of AIME, 1966, v. 236, pp. 642-646. See also in: Stereology, L. - N.Y. - Berlin, Springer, 1968, pp. 250-255.

30. Saltykov S.A. Stereometric metallography. M .: Metallurgy, Publishing. 3rd 1970.376 s .; see also Chernyavsky K.S. Stereology in metal science. M .: Metallurgy, 1977.280 s., See p. 212-214.

31. Wentzel E.P. Probability theory. M .: Fizmatgiz, 1962.

32. Batutina L.S. Intensification of cement hardening by preliminary surface hydration. Abstract. diss. for a job. student Art. Cand. tech. sciences. M .: NIIcement, 1984. 24 p.

33. Lamekin N.S. Cavitation: theory and application. Gos. nat. Russian academy. M .: Rusaki, 2000.246 s., See p. 68.

34. Buffalo B. N. Thin caverns in flows with disturbances. K .: Naukova Dumka, 1980.296 s., See p.266.

35. Birkhoff T. et al. Jets, tracks and caverns. M.: Mir, 1964. 466 p. See also Pernik A. D. Problems of cavitation. L .: Sudpromgiz, 1966.643 s.

36. Epstein L.A. Methods of the theory of dimension and similarity in problems of hydromechanics of ships. L .: Shipbuilding, 1970.247 s.

37. Kulagin V.A. et al. Modeling of two-phase cavitation flows. Krasnoyarsk, Krasnoyarsk state. tech. un-t 2001, 187 p.

38. Makarov V.V. Study of plane cavitation vortices and axisymmetric jet flows. Abstract. diss. for a job. student step. Cand. physical - mat. Sciences, Cheboksary, Chuvash, state. un-t, 2000.15 s.

39. Kalishchuk A.L. et al. Handbook for the production of precast concrete. K .: “Alarm Clock”, 1964, 347 p., See p. 57.

40. Khayutin Yu. G. Study of issues of separate concreting with injection of activated solution into coarse aggregate. Abstract. diss. for a job. student step. Cand. tech. sciences. M .: NIIZHB, 1964, 21 p.

41. GOST 24211-91. Additives for concrete. General specifications.

42. GOST 30459-96. Additives for concrete. Methods for determining effectiveness.

43. TU 5730-003-23454867-02. Additive “Dilafilm” for cement, cement dry mixes and concrete.

44. Zvezdov A.I. Physico-mechanical properties of slag concrete on tensile cement. Abstract. Cand. diss. for a job. student step. Cand. tech. sciences. M .: NIIZHB, 1981, 20 p.

45. Udachkin I.B. and others. Foam concrete: results and development prospects / Building materials, 2003, No. 3, p.5 and below.

46. GOST 310.2-76. Cement. Methods for determining the fineness of grinding.

47. TU 5730-001-23454867-01. Low water demand cement disaggregated for corrosion-resistant concrete “D-TsNV”. M .: 2001.

48. TU 5743-026-00369171-01. Modifier for cement MTs-1. M., 2001.

49. GOST 11052-74 Expanding gypsum-alumina cement. Technical conditions

50. Eurasian patent No. 002673, 2002.

51. Kaprielov S.S. and others. High-strength concrete with organomineral modifiers of the MB series. Structure and properties. // 1st All-Russian Conference on Concrete and Reinforced Concrete. “Concrete at the turn of the 3rd millennium. In 3 books, M .: "Gothic", 2001, Prince. 2nd, pp. 1019-1026.

52. TU 2455-005-00281039-03. Technical modified lignosulfonates - “Plasticizer LSTM-12”

53. TU 2481-001-51831493-00. Superplasticizer S-3

54. TU 13-0281036-029-94. Technical lignosulfonates.

55. GOST 6552-80. Phosphoric acid. Technical conditions

56. GOST 450-77. Technical calcium chloride. Technical conditions

57. GOST 3759-75. Aluminum chloride 6-water. Technical conditions

58. GOST 4166-76. Sodium sulfate. Technical conditions

59. GOST 12966-85. Aluminum sulfate technical purified. Technical conditions

60. GOST 6981-75. Vitriol iron technical. Technical conditions

61. GOST 5494-95. Powder aluminum. Technical conditions

62. Keves P.D. and others. Aerated concrete on perhydrol. M .: Gosstroyizdat, 1961, 115 p.

63. TU 2453-013-10644738-00. Saponified wood resin (SDO-L).

64. Bazhenov Yu. M. Concrete technology. M .: Higher. School, 1978. 455 p.

65. Tarnarutsky G.M. Development of technology and study of the construction and technical properties of hydrophobic Portland cement with multicomponent additives. Abstract. diss. student step.kand. tech. Sciences, Moscow: NIIcement, 1974, 35 p.

66. GOST 10834-76. Water-repellent fluid 136-41. Technical conditions

67. TU 5730-007-23454867-03. Clinker sulfoaluminate.

68. GOST 6139-91. Normal sand for cement testing. Technical conditions

69. GOST 8736-93. Sand for construction work. Technical conditions

70. GOST 8267-93. Crushed stone and gravel from dense rocks for construction work. Technical conditions

71. GOST 10832-91. Expanded perlite sand and crushed stone. Technical conditions

72. GOST 23732-79. Water for concrete and mortar. Technical conditions

73. GOST 310.4-81 Cements. Methods for determining the tensile strength in bending and compression

74. Kravchenko I.V. ct, al. VI International Congress on Differential Thermal Analysis (DTA). Wiesbaden: Bauverlag, 1977, s. 87. See also Copeland L.E. et al. Journal of Portland Cement Assoc. Research and Develop. Laboratories, 1962, v. 4, No. 2; see also: Barta R. Chemie a techologie cementu. Praha. Nakl. CAV, 1961, 1107 s., Wiz. s. 950; Taylor X. The chemistry of cement. M .: Mir, 1996, 560 s., See p. 241-243 (data on DTA cement at an early age), 249 (data on pp in fully hydrated cement).

75. Yudovich B.E. Study of the features of grinding, particle size distribution and construction and technical properties of high-strength Portland cement. Abstract. Iss. on the competition. student Art. Cand. tech. sciences. M .: NIIITsement, 1972. -31 p., See p. 25 and below.

76. Stern F. Stirring and apparatuses with stirrers. L .: Chemistry, 1975.

77. Bauman V.N. et al. Mechanical equipment of enterprises of building materials, products and structures. M.: Mechanical Engineering, 1981, p. 270-272. 78. RF patent No. 2036090, cl. B 28 C 5/16, 1991 (prototype for a mixer).

Claims (15)

1. A method of producing a cement-water suspension, comprising mixing a hydraulic binder, mainly cement, with water or with a filler and water with physico-mechanical activation of cement in the composition obtained in a mixing device in the field of centrifugal forces of a cement-water suspension, characterized in that the specified activation is carried out with cavitation, intensified by blowing the specified suspension with its sparging with compressed air while regulating at least during part of the mixing time, is significant the number of cavitation φ in the range from 3.8 to 0.6 · 10 ^-4 , while the number of cavitation is determined by the formula:

where k ₁ - coefficient of pressure loss of the mixing device during cavitation, equal to 0.55-0.8; ΔН is the difference in the hydraulic pressure of the mixing device and the pressure of saturated water vapor in the caverns at 20 ° C equal to 0.03 MPa, which characterizes the cavitation field and is selected in the range 0.25-1.2 MPa; k ₂ is the pressure loss coefficient of the blown-in compressed air, equal to an average of 0.5; ΔР is the pressure difference between the pressurized compressed air and the pressure of saturated water vapor in the caverns, selected in the range of 100-250 kPa; η is the current viscosity of the prepared cement-water suspension or products based on it, maintained in the range of 16-1770 Pa · s, and during bubbling in the range of 20-130 Pa · s; ρ is the current density of the specified cement-water suspension or products based on it, kg / m ³ ; g is the acceleration of gravity equal to 9.81 m / s ² ; π - 3.14; R is the current radius of the specified field of centrifugal forces, selected in the range of 0.3-1.2 m; n is the frequency of rotation of the working body of the mixing device, selected in the range of 300-6000 rpm, or 5-100 s ^-1 , and the specified activation of the suspension is carried out until the degree of initial hydration of the cement is achieved according to the criterion of an increase in losses during calcination from the beginning of mixing of the suspension to the moment of its setting, at least 2.5 wt.%. 2. The method according to claim 1, characterized in that as the specified cement use material from the group: Portland cement, slag Portland cement, sulfate-resistant Portland cement, pozzolanic Portland cement, low water demand cement, expanding or non-shrink cement, these cements based on promoted clinkers, mixtures of these cements . 3. The method according to any one of claims 1 and 2, characterized in that the filler is introduced into the suspension during cavitation and / or after it. 4. The method according to any one of claims 1 to 3, characterized in that a powder material with a specific surface by the method of breathability in the range of 200-1500 m ² / kg is used as a filler. 5. The method according to claim 4, characterized in that as the specified powdered material using ground sand or cullet or brick fight or fly ash at wt. the ratio of the clinker part of the specified cement and the specified powdery material from 1: 0.05 to 1: 1. 6. The method according to any one of claims 1 to 5, characterized in that a fine aggregate is additionally introduced into the specified suspension during cavitation and / or after its completion. 7. The method according to claim 6, characterized in that as the specified fine aggregate use standard sand or particularly fine sand or silty sand or sand dune, or mixtures thereof, by weight. the ratio of the specified cement and the specified fine aggregate from 1: 0.3 to 1: 4. 8. The method according to any one of claims 1 to 7, characterized in that a commodity dry mixture of a hydraulic binder, filler, filler and additives is added to the specified suspension during cavitation and / or after its completion. the ratio of the specified cement and hydraulic binder in the composition of the specified dry mix from 1: 0.1 to 1:15. 9. The method according to any one of claims 1 to 8, characterized in that the average specific energy field of the centrifugal force field during the preparation of the specified suspension with sparge is selected in the range of 1.8-225 kJ / m ³ . 10. The method according to any one of claims 1 to 9, characterized in that additives for concretes from the groups are additionally added to the specified suspension during bubbling or at the end of it: I - plasticizing, or water-reducing; II - water retention, or improving pumpability; III - retarders setting and hardening; IV - accelerators setting and hardening; V - clogging pores; VI - gas generating; VII - air entraining; VIII - antifreeze; IX - hydrophobic, in concentrations of 50-70 wt.% Their optimal values, selected in the conditions of free access of atmospheric carbon dioxide, and / or anti-shrink additives, the inorganic basis of which are sulfoaluminate clinker and / or aluminum sulfate, additionally including a peptizing component, and namely, a mixture of an organic etchant and film-forming agents, when the mass ratio of the inorganic base and the indicated ingredients in the anti-shrink additive is 100: (0.5-20) :( 0.3-15) and the mass ratio of Portland cement second portion of clinker in cement and antisettling additives introduced into the cement-water slurry or the products based on it 100: (0,6-3,5). 11. The method according to any one of claims 1 to 10, characterized in that sodium or calcium polymethylene polynaphthalene sulfonates or technical modified lignosulfonates or technical modified lignosulfonates are taken as plasticizing or water-reducing additives, methylcellulose, polyoxyethylene or polyoxyethylene are used as water-retaining or pumping additives molasses or orthophosphoric acid or nitrilotrimethylene phosphonic acid are taken as retarders and hardeners; as retarders and hard they take potash or calcium chloride or sodium chloride or aluminum chloride or sodium sulfate or trisodium phosphate or a mixture thereof, as additives that clog pores, take aluminum sulfate, iron sulfate, iron chloride, and aluminum powder or hydrogen peroxide in the mixture are taken as gas-forming additives with calcium oxychloride, as an air-entraining additive take a washed wood resin or a neutralized air-entraining resin or sodium ethylsiliconate, take sodium nitrite or nitrate as antifreeze additives calcium nitrate-chloride, as a hydrophobic additive, take a solution of high molecular weight fatty acids in mineral oil or polyhydrosiloxanes, and as a shrink additive take a mixture of the first inorganic base of the latter - sulfoaluminate clinker, which includes at least 30 wt.% calcium sulfoaluminate, and a peptizing component - the composition of the etchant and film former, specifically mannuronic acid or mannitol alcohol and calcium stearate, or a mixture of a second inorganic base anti-shrink add c - aluminum sulphate and peptizing said component. 12. The method according to any one of claims 1 to 11, characterized in that the suspension is subjected to additional mixing with the introduction of coarse aggregate or a mixture of coarse and fine aggregates, as well as water and the preparation of mortar or concrete mixtures, including hydrated neoplasms of cement obtained by it specified pre-activation, as seeds. 13. The method according to p. 12, characterized in that as the specified small and / or large aggregates use materials from the groups: I - of natural origin, including silicate rocks and / or minerals, in particular granite and / or quartz, and / or carbonate rocks, in particular limestone and / or dolomite, and / or II of artificial origin, prepared from expanded rocks, including aluminosilicates, in particular expanded clay or glassite or perlite, or from artificial porous materials, in particular foam . 14. A device for implementing the method of producing a cement-water suspension, made in the form of a mixer for producing a cement-water suspension, containing a stirrer located in a cylindrical chamber, including an open turbine rotor with radial arc blades on a disk facing the bottom of the mixer chamber and cantilevered on a vertical shaft located in the Central hole of the bottom with an annular gap, and also containing a lower drive shaft, a hatch for supplying the source components and the discharge pipe with a shutter, o characterized in that the bottom of the chamber is equipped with a stuffing box with a seal for the shaft, the cavity of which is made in communication with the working space of the camera by means of an annular gap, while the ratio of the cross-sectional areas in the light of the chamber and the annular gap is 1100-325000, the stuffing box is equipped with a fitting for supplying compressed air into its cavity, and the discharge pipe is tangentially connected to the chamber. 15. The device according to 14, characterized in that the hatch is equipped with a loading nozzle made in the form of a return cone located in the chamber coaxially with the mixer, while the lower edge of the cone is separated from the upper edge of the chamber by a distance of 1 / 3-1 / 2 heights of the latter.

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