EA029570B1 - Method for production of porous granulated building material - Google Patents

Abstract

The invention is related to the field of building materials that can be used as heat-insulation materials, as a filler for building mixes, as a protective finishing layer and as a mortar. The method for production of porous granulated building material includes grinding of porous silica raw material containing at least 70 wt.% of amorphous SiOto produce silica sand, dosing of the produced sand and air-dry granulated caustic alkali, loading into a mixer, mixing accompanied by self-heating to produce a hot viscous mixture. The method uses a planetary-type mixer equipped by a heater, sensors monitoring the load and the motor temperature being able to control mixture viscosity in the course of mixing. The mixture is discharged to a press extruder, or to a pelletizer, or to rollers to produce semiproducts.

Description

The invention relates to the field of building materials that can be used as insulation materials, as a filler for building mixtures, as a protective and finishing layer and masonry mortar. The method of obtaining a porous granulated building material includes grinding a porous silica raw material containing at least 70 wt.% Amorphous δίθ ₂ to obtain silica sand, dosing the obtained sand and air-dry granulated caustic alkali, loading into the mixer, mixing, followed by self-heating to obtain hot viscous mixture. The method uses a planetary-type mixer equipped with a heater, load control sensors and engine temperature with the ability to control the viscosity of the mixture during the mixing process. Unloading the mixture produced in a press extruder or granulator or rollers, followed by the production of semi-finished products.

029570

The invention relates to the field of building materials, and in particular to methods for producing porous granulated building materials, which can be used as insulating materials, as a filler for building mixtures, as a protective finishing layer and masonry mortar.

Known [1] a method of manufacturing a solid hydrosilicate gel, including grinding a porous silica raw material containing at least 70 wt.% Amorphous δίθ ₂ , to obtain silica sand, dosing this sand and air-dry granulated caustic alkali, loading them into the reactor with the agitator switched on and mixing, accompanied by self-heating, to obtain a hot viscous semi-finished product, unloading the hot viscous semi-finished product into containers and holding this semi-finished product in containers with gradual natural cooling to a temperature that is close to the ambient temperature, to obtain a mature solid hydrosilicate gel.

The disadvantage of this method is the lack of technological continuity of the process. During the preparation of the mixture, the main difficulty lies in the visual control of the optimal viscosity of the mixture. If the viscosity exceeds the optimum value, difficulties arise, both with cleaning the mixer from the mixture stuck to its part, and with unloading this mixture. In order to avoid this, in the indicated method [1], the mixture that has not reached the optimal viscosity is manually discharged into containers, which is rather laborious and is held until it solidifies at ambient temperature. In this case, the process of solidification is characterized by duration, and the readiness of the product is determined only visually. The porous material obtained in this way dissolves in water, has a reduced compressive strength, and is broken with stirring.

The problem to which the invention is directed, was to ensure the continuity of the process, the ability to automatically control the viscosity of the mixture. The same task was to obtain a porous material with improved qualities.

The problem is solved by the claimed method, including grinding a porous silica raw material containing at least 70 wt.% Amorphous δίθ ₂ , to obtain silica sand, dosing the obtained sand and air-dry granulated caustic alkali, loading them into the mixer, mixing, followed by self-heating, to get a hot viscous semi-finished product, while in the method they use a planetary-type mixer equipped with engine load monitoring devices with the possibility of controlling the viscosity and the mixture during stirring, and discharging the mixture produced in the extruder or press roll crusher followed by obtaining intermediates.

In a preferred embodiment of this method in the process of mixing in a mixture of silica raw materials and alkali impose water-retaining additive, the volume of which is 1-7% by weight of dry matter of the silica raw materials.

In another preferred embodiment of the process, the water retention aid is added during the self-heating of the mixture.

In another embodiment of the method, in the process of mixing, a strengthening additive is introduced into the mixture of silica raw materials and alkali, the volume of which is 1-7% by weight of the dry matter of the silica raw materials.

In another embodiment, the implementation of the claimed method in the process of mixing in a mixture of silica raw materials and alkali impose a pore-forming additive, the volume of which is 1-7% by weight of dry matter of the silica raw materials.

In another embodiment of the inventive process, the water retention aid is selected from the group boric acid, glycerin, sodium aluminate, tetraammine zinc hydroxide, ammonium orthoborate.

In another embodiment of the method, the reinforcing additive is selected from the group of Na bicarbonate, alkali metal chloride, aqueous solution of sodium silicate, silicic acid gel, sodium bicarbonate, and silicofluoric acid.

In another embodiment of the method, the pore-forming additive is selected from the group boric acid, aluminum powder, carbon black, glycerin, silicon carbide, glycol.

In a preferred embodiment of the method, the silica raw materials are crushed to a fraction of not more than 0.5 mm.

In another preferred embodiment of the inventive method, the crushed silica raw material is moistened with a supply of water with a temperature of 70-95 ° C to the mixer before the supply of alkali to it.

In a preferred embodiment of the process, tripoli is used as the silica raw material.

The use of a planetary-type mixer in the method, equipped with engine load monitoring instruments, allows for a continuous cycle of the technological process. Monitoring the viscosity of the mixture in the mixing process is carried out on the basis of indications of instruments for monitoring engine load. With an increase in the viscosity of the mixture, the load on the mixer motor increases, and the viscosity reaches the optimum value when the engine load monitor triggers. The optimal viscosity index is determined empirically specifically for each type of mixer. Also, the mixer has design features that consist in the presence of special- 1 029570

frame and knives for cutting the mixture with a certain degree of viscosity. Also with the introduction of a mixture of water-retaining, hardening and pore-forming additives was obtained technical result, which consists in obtaining a porous material with improved performance compared with the product obtained as a result of the method implemented in the prototype. Boron acid, glycerin, sodium aluminate, tetraammine zinc hydroxide, and ammonium orthoborate are used as water retaining additives, which allows reducing the water absorption of the obtained porous material. Alkali metal chloride, an aqueous solution of sodium silicate, silica gel, sodium bicarbonate, and hydrofluoric acid, are used as reinforcing additives, which makes it possible to achieve increased strength of the porous material and prevent its destruction by mixing. As a pore-forming additives used, in particular, gas-forming, such as aluminum powder, carbon black, glycerin, silicon carbide, glycol, which provides increased porosity of the material obtained and, accordingly, low density and low thermal conductivity. It is important to observe the quantitative proportions of the introduction of additives, namely, within 1-7% by weight of the dry matter of the silica raw materials, as well as the sequence of the introduction of additives into the mixture. So the water-retaining additive is fed during the self-heating of the mixture, since during this period it dissolves better, and the hardening and pore-forming additives are supplied during the period of bringing the rock to a certain humidity.

The invention is illustrated by the scheme.

The implementation of the invention

They make grinding of tripoli to a fraction of 0.5 mm or less. Perhaps up to 30 and 50 microns, which depends on the equipment for grinding. The crushed fraction should not contain particles greater than 0.5 mm. Humidity of tripoli is in the range of 5-45%, while the optimum humidity is 40%. At a humidity of 5-10%, you must add water. The temperature of the water is preferably 60-90 ° C. It is also preferable that at the beginning of the process the temperature of the tripoli is about 20 ° C. With increasing temperature, the speed of the process increases. The dosage and supply of the components to the mixer occurs mechanized through the hopper. Initially, silica sand is fed into the working mixer, then, if necessary, the humidity of the tripoli is brought to 40% with hot water and the reinforcing and blowing agents are fed. Then, an alkali (Να подают) is fed through the loading hatch into the working mixer. When these components are mixed, the mixture is self-heating. Additives are served during mixing. Water-holding additive serves mainly during the self-heating of the mixture, since at this time it dissolves better. For the implementation of mixing using a mixer with a special frame and knives to eliminate sticking of the mixture. In addition, it is preferable that the mixer is heated, especially in winter. Heating is carried out in the range of 50-60 ° C. To determine the optimal temperature, a temperature sensor can be installed on the mixer. Also, the mixer is equipped with a load sensor to monitor the viscosity of the mixture. The mixing time depends on the type of mixer, mainly its power, and the load parameters characterizing the viscosity of the mixture are determined empirically for each type of mixer. In the process of mixing, the viscosity of the mixture gradually increases, which leads to an increase in the load on the mixer motor. When the engine reaches a certain load, the thermal relay is activated, which is an indicator of the optimal viscosity of the mixture. The mixture obtained in this way has an optimal viscosity for unloading the mixture into a press extruder or roller grinder. The semi-finished product obtained as a result of passing the mixture through an extruder or rollers is cooled and fed to a grinder. The size of the product leaving the shredder depends on its subsequent purpose. As a grinder, a disintegrator is preferably used. In the disintegrator receive fractions of 1-3 mm, depending on the destination of the final product. Then grinding to a fraction of 30-50 microns. After grinding to the desired fraction, the product is fed into a dryer to remove physical water and reduce moisture to 5%. In case the moisture content of the product is above the specified limit, the final product will have a torn shell. Then the product from the dryer is fed to the porous oven, which operates on the principle of a fluidized bed at a temperature of 340-540 ° C. Then, pellets are fed from a porous oven into a classifier refrigerator, which cools the product and distributes it into fractions. In the refrigerator classifier the final product is cooled to 60 ° C and distributed into fractions: 0.5-1 mm, 1-2 mm, 2-3 mm. Then these fractions are fed into bunkers or other containers and used for their intended purpose as a masonry mortar and a binder in building mixtures, or as a protective and finishing layer, or as a heater.

Examples of specific implementation of the claimed invention

Example 1

As a silica raw material, tripoli was used, the content of δίΟ ₂ in which was 81%, humidity 30%. The tripoli was crushed to a fraction of 50 μm (grinding was performed on a DM2 disintegrator). At the beginning of the process, the tripoli temperature was 20 ° C. The tripoli was poured into the hopper and then fed into the working mixer, the humidity of the Tripoli was adjusted to 40% by moistening with hot water. For the process, a planetary-type mixer was used, equipped with a heater, temperature sensors, and a thermal relay. Then in the mixer through the loading hatch filed

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Alkali Naaon. In the process of mixing the tripoli and dry caustic soda, the mixture was self-heating. Stirring was carried out to a certain viscosity, until the operation of the thermal relay. Next, the mixture was unloaded into a press extruder, pellets of 10 by 10 mm were obtained. Then cooled pellets were fed to the chopper. In order to obtain a porous material intended as a filler, a disintegrator was used. Using a disintegrator, a fraction of 0.5 to 2 mm was obtained. The moisture content of the obtained product was 40-50%. Then the product was fed from the disintegrator to the dryer to reduce the moisture to 5%. From the dryer, the semi-finished product was fed to the feed kiln. The specified device works on the principle of fluidized bed. After that, the resulting material was fed into the refrigerator-classifier for the separation of the product into three fractions. Refrigerator classifier performs two functions: cooling and classification. In the refrigerator classifier, the product was cooled to 60 ° C. The result was a product divided into three fractions: from 0.5 to 1 mm, from 1 to 2 mm, from 2 to 3 mm.

The fraction from 0.5 to 1 mm was used as a masonry mortar and a binder in mixtures. The fraction from 1 to 2 mm was used as a protective and finishing layer.

The fraction from 2 to 3 mm was used as insulation.

The quantitative composition for example 1 ._____

Tripoli with content 5U ₂ 81% Alkali No.ON 96.6% in dry form in the amount of 19% by weight of dry substances water retention additive without hardening additive without blowing agent without

As a result, we obtained granules with the following characteristics:

Fraction size (mm) 0.5-1 1-2 2-3 Bulk density (kg / m3) 220 140 110 Bulk water absorption more than 45% Shell view porous

Example 2

As a silica-containing raw material, tripoli was used, the content of δίθ ₂ in which was more than 79.5%, the humidity of 30%. The tripoli was crushed to a fraction of 50 μm (grinding was performed on a DM2 disintegrator). At the beginning of the process, the tripoli temperature was 20 ° C. The tripoli was poured into the metering hopper and then fed into the working mixer, the humidity of the Tripoli was adjusted to 40% by moistening with hot water (with a temperature of 90 ° C). For the implementation of the method used planetary mixer type, equipped with a heater, temperature sensors, thermal relay. Alkaline NaOH and sodium bicarbonate were fed to the mixer through the loading hatch to harden the shell and reduce the size of pores on the shell. In the process of mixing the tripoli and dry sodium hydroxide, the mixture was self-heating. Mixing the components of the mixture was carried out to a certain viscosity, which was controlled by the thermal relay of the mixer. When the optimum viscosity of the mixture was reached after the operation of the thermal relay of the mixer motor, the mixture was unloaded into a press extruder, pellets measuring 10 by 10 mm were obtained. Then cooled pellets were fed to the chopper. In order to obtain a porous material intended as a filler, a disintegrator was used. Using a disintegrator, a fraction of 0.5 to 2 mm was obtained. The humidity of the obtained product was 45%. Then the product was fed from the disintegrator to the dryer to reduce the moisture to 5%. From the dryer, the semi-finished product was fed to the feed kiln. The specified device works on the principle of fluidized bed. After that, the resulting material was fed into the refrigerator-classifier for the separation of the product into three fractions. Refrigerator classifier performs two functions: cooling and classification. In the classifier refrigerator, the product was cooled to 60 ° C.

The result was a product divided into three fractions: from 0.5 to 1 mm., From 1 to 2 mm, from 2 to 3 mm.

The fraction from 0.5 to 1 mm was used as a masonry mortar and a binder in mixtures.

The fraction from 1 to 2 mm was used as a protective and finishing layer.

The fraction from 2 to 3 mm was used as insulation.

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The quantitative composition for example 2.

Bergmeal with 5U content ₂ 79.5% 79.5% Alkali Haon 96.6% dry in the amount of 19% by weight of dry substances water retention additive without hardening additive Sodium bicarbonate 1.5% on dry matter blowing agent without

As a result, we obtained granules with the following characteristics:

Fraction size (mm) 0.5-1 1-2 2-3 Bulk density (kg / m3) 280 180 160 Bulk water absorption more than 38% Shell view micropores

Example 3

As a silica-containing raw material, tripoli was used, the content of δΐθ ₂ in which was 78%, humidity 30%. The tripoli was crushed to a fraction of 50 μm (grinding was performed on a DM2 disintegrator). At the beginning of the process, the tripoli temperature was 20 ° C. The tripoli was poured into the metering hopper and then fed into the working mixer, the humidity of the Tripoli was adjusted to 40% by moistening with hot water (with a temperature of 90 ° C). For the process, a turbulent type mixer was used, equipped with a heater, temperature sensors, and a thermal relay. Alkaline NaOH, hydrocarbonate and carbon blowing agent were fed to the mixer through the loading hatch. In the process of mixing the tripoli and dry caustic soda, the mixture was self-heating. Stirring was carried out to a certain viscosity, until the operation of the thermal relay. Next, the mixture was unloaded into a press extruder, pellets of 10 by 10 mm were obtained. Then cooled pellets were fed to the chopper. In order to obtain a porous material intended as a filler, a disintegrator was used. Using a disintegrator, a fraction of 0.5 to 2 mm was obtained. The humidity of the obtained product was 45%. Then the product was fed from the disintegrator to the dryer to reduce the moisture to 5%. From the dryer, the semi-finished product was fed to the feed kiln. The specified device works on the principle of fluidized bed. After that, the resulting material was fed into the refrigerator-classifier for the separation of the product into three fractions. Refrigerator classifier performs two functions: cooling and classification. In the classifier refrigerator, the product was cooled to 60 ° C. The result was a product divided into three fractions: from 0.5 to 1 mm, from 1 to 2 mm, from 2 to 3 mm. The fraction from 0.5 to 1 mm was used as a masonry mortar and a binder in mixtures. The fraction from 1 to 2 mm was used as a protective and finishing layer. The fraction from 2 to 3 mm was used as insulation.

The quantitative composition for example 3.

Bergmeal with 5U ₂ content (78%) 78% Alkali Haon 96.6% dry in the amount of 19% by weight of dry substances ί water retention additive without hardening additive Sodium bicarbonate 1.5% on dry matter blowing agent Carbon black 1.5% on dry matter

As a result, we obtained granules with the following characteristics:

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Fraction size (mm) 0.5-1 1-2 2-3 Bulk density (kg / m3) 200 150 100 Bulk water absorption more than 35% Shell view micropores

Example 4

As a silica-containing raw material, tripoli was used, the content of δΐθ ₂ in which was more than 76.5%, the humidity of 30%. The tripoli was crushed to a fraction of 50 μm (grinding was performed on a DM2 disintegrator). At the beginning of the process, the tripoli temperature was 20 ° C. Tripoli was poured into the metering hopper and then fed into the working mixer, the humidity of the Tripoli was adjusted to 40% by moistening with hot water with a temperature of 75 ° C. For the process, a planetary-type mixer was used, equipped with a heater, temperature sensors, and a thermal relay. Alkaline IaOH, sodium bicarbonate and boric acid (as a pore-forming agent and to reduce water absorption) were fed into the mixer through the loading hatch. In the process of mixing the tripoli and dry caustic soda, the mixture was self-heating. Stirring was carried out to a certain viscosity, until the operation of the thermal relay. Next, the mixture was unloaded into a press extruder, pellets of 10 by 10 mm were obtained. Then cooled pellets were fed to the chopper. In order to obtain a porous material intended as a filler, a disintegrator was used. Using a disintegrator, a fraction of 0.5 to 2 mm was obtained. The moisture content of the obtained product was 40-50%. Then the product was fed from the disintegrator to the dryer to reduce the moisture to 5%. From the dryer, the semi-finished product was fed to the feed kiln. The specified device works on the principle of fluidized bed. After that, the resulting material was fed into the refrigerator-classifier for the separation of the product into three fractions. Refrigerator classifier performs two functions: cooling and classification. In the classifier refrigerator, the product was cooled to 60 ° C. The result was a product divided into three fractions: from 0.5 to 1 mm, from 1 to 2 mm, from 2 to 3 mm. The fraction from 0.5 to 1 mm was used as a masonry mortar and a binder in mixtures. The fraction from 1 to 2 mm was used as a protective and finishing layer. The fraction from 2 to 3 mm was used as insulation.

The quantitative composition for example 4.

Tripoli with content 5U ₂ 76.5 Alkali ΝθΟΗ 96.6% in dry form in the amount of 19% by weight of dry substances water retention additive Boric acid 1.5% on dry substance hardening additive Sodium bicarbonate 1.5% on dry matter blowing agent Boric acid 1.5% on dry substance

As a result, we obtained granules with the following characteristics:

Fraction size (mm) 0.5-1 1-2 2-3 Bulk density (kg / m3) 180 120 90 Bulk water absorption no more than 24% Shell view micropores

Claims (11)

CLAIM 1. A method of obtaining a porous granulated building material, including grinding a porous silica raw material containing at least 70 wt.% Amorphous δΐθ ₂ , to obtain silica sand, dosing the obtained sand and air-dry granulated caustic alkali, loading metered sand and alkali into the mixer, mixing, followed by self-heating, to obtain a hot viscous mixture, characterized in that the method uses a mixer plan 5 029570 container type, equipped with a heater, sensors controlling the load and temperature of the engine with the ability to control the viscosity of the mixture during mixing, and the mixture is unloaded into a press extruder or granulator or rolls, followed by obtaining semi-finished products. 2. The method according to p. 1, characterized in that in the process of mixing in a mixture of silica raw materials and alkali impose water-retaining additive, the volume of which is 1-7% by weight of dry matter of silica raw materials. 3. The method according to claim 1 or 2, characterized in that the water-retaining additive is introduced during the self-heating of the mixture. 4. The method according to claim 1, characterized in that during the mixing process, a reinforcing additive is introduced into the mixture of silica raw materials and alkali, the volume of which is 1-7% by weight of the dry substance of the silica raw materials. 5. The method according to claim 1, characterized in that during the mixing process a pore-forming additive is introduced into the mixture of silica raw materials and alkali, the volume of which is 1-7% by weight of the dry matter of the silica raw materials. 6. The method according to claim 1 or 2, characterized in that the water-retaining additive is selected from the group comprising boric acid, glycerin, sodium aluminate, tetraammine zinc hydroxide, ammonium orthoborate. 7. The method according to claim 1 or 4, characterized in that the strengthening additive is selected from the group including Na bicarbonate, alkali metal chloride, aqueous solution of sodium silicate, silica gel, sodium bicarbonate, silicofluoric acid. 8. The method according to claim 1 or 5, characterized in that the pore-forming additive is selected from the group comprising boric acid, aluminum powder, carbon black, glycerin, silicon carbide, glycol. 9. The method according to claim 1, characterized in that tripoli is used as the silica raw material. 10. The method according to claim 1 or 9, characterized in that the silica raw materials are crushed to a fraction of not more than 0.5 mm. 11. The method according to claim 1, characterized in that the crushed silica raw material is moistened with a supply of water with a temperature of 70-95 ° C to the mixer before the supply of alkali to it.