DD301404A7 - Process for the production of heat-resistant and refractory building materials - Google Patents

Abstract

The invention entitled "Process for producing heat-resistant and refractory building materials" relates to the production of special refractory building materials for pyrotechnic equipment. The object of the invention is that the energy consumption is avoided by the usual firing process in the classical heat-resistant and refractory bricks. The invention solves the problem of being able to produce conventional, non-plastic, heat-resistant and refractory building materials using aluminosilicate binders capable of undergoing heat treatment. The essence of the invention is expressed by the fact that the aluminative binder z. As clay, kaolin and / or a -Al ind 2 O ind 3, sulfite powder o. added, processed together to form a highly active binder component via Mischmahlung or only homogenization and then used as a bond on the heat treatment solidifying binder for incorporation of silicate or non-silicate raw materials according to known technologies.

Description

The purpose of the Frfindung is to turn off this Nachtoilo completely.

The invention has for its object to provide a new method for the production of heat-resistant and refractory materials.

According to the invention, this object is achieved in that silicate and / or nltrechtichiatic raw materials wetted in known mixing composition in a mixing unit with water or water-Sulphatablauge mixture up to 15Ma .-%, with a Warmbohandlungszement on an aluminate basis as a binder * rsetzt, homogenized, on known Formgebungsolnrichtungen pressed into molds and then heat treated. The advantages of such a procedural solution are that once the modern assembly method with species-specific, but in the format but strongly divergent materials can be useful supplemented and on the other for this conventional conventional in the refractory industry brick formats no enorgieaufwendigor burning process is required. Furthermore, the advantages consist in that the texture is formed by the use of compression compaction at specific pressures greater than 10 MPa as in the classic refractory materials, which leads to significantly improved thermomechanical properties at temperatures in the critical temperature range and classification temperature compared to the heat-resistant and refractory precast concrete. This in turn results in improved wear resistance during abrasion.

The invention will be explained in more detail in the embodiments.

Export billet I

A CA / CAj cement with approx. 70% Al ₂ Oj is homogenized with the addition of 20% dried kaolin and 0.5% sulphite powder in a mixing drum in the presence of large-volume sintered corundum grinding media. It is desirable that the heat treatment cement thus produced passes without residue, the 90-micron sieve. The leaning agent, in this case Kaolinrohschamotte in the grain size 0 to 1 and 1 to 3mm, is moistened with a water-sulfite liquor mixture, dilution 10: 1. Thereafter, in the suitable mixing unit, the addition of the binder on the basis of a heat treatment cements and the final mixing of Preßgomenges, the Preßgemenge with the composition of based on dried substance -

20% by weight of heat treatment cement 1400 (consisting of CA / CA ₂ cement, kaolin and sulphite powder), 40% by weight of kaolin raw ash 0 to 1 mm and 40% by weight of kaolin raw ash 1 to 3 mm

is to be pressed within 1 hour to the desired stones of different geometry. This is followed by an intermediate storage in a closed room with H ₂ O vapor-saturated atmosphere and usual room temperatures up to 24 hours. Then the heat treatment lasting several hours to 100 ⁰ C and in likewise saturated with water vapor atmosphere. After 15 hours, for example, heat treatment and subsequent drying to constant mass the suitable for application temperatures up to 1400 ⁰ C. Materials characterized by the following characteristics.

Compressive strength in MPa 43.2

Compressive strength in MPa after fire

at 115O ⁰ C and 4-hour hold time 32.3

Length change after fire at 150 ° C

and 4-hour hold time in% -0.1

Length change after fire at 1 400 ⁰ C

and 4-hour hold time in% -0.2

Druckfuuerbeständigkeit bei

2 kp / cm ² load T ₀₆ in ⁰ C 1480

Thermal shock resistance,

Number of deterrents, η 25

Implementation Chart 2

For a high-temperature material, in which fused alumina is used as a leaning agent, the CA / CA ₂ cement with approx. 70% AI ₂ Oj to a heat treatment cement with approx. 85% AI ₂ Oj be implemented.

This is necessary to eliminate the later CAj formation in view of the re-growth of the building material at high temperatures and on the other hand to give the freshly pressed stone a high edge strength. En oicht is the above by the addition of a ground or activated in the presence of sulfite powder alumina.

For the exemplary embodiment, calcined alumina was ground to TGL 7750 with the addition of 1% sulphite powder so that the residue at 40pm max. 8% involved; the residue at 63 and 90pm was 0%. (This Spozial clay was mixed with the CA / CA ₂ cement 1: 1.) Of this high alumina thermal treatment cement, 20% by mass was used as the binder, ie, in principle, the cement content was only 10% by mass.

After the composition of the two pressing amount of

I Il Heat treatment cement 1700 20Ma .-% 20Ma .-% (consisting of CA / CAj cement, highly active clay and sulphite powder) White corundum, grain size 00 WS 10ma .-% - White corundum, grain size 25 10ma .-% 20Ma .-% White corundum, grit 63 20Ma .-% 20Ma .-% White corundum, grit 160 40ma .-% 40ma .-%

and per kg of 55 ml water-sulfite waste liquor mixture, 4: 1 diluted, as Preßgemengefeuchte were prepared after conditioning of Preßgemenges at a pressure of 100MPa body after molding in a gescheossenen container in H ₂ O vapor saturated atmosphere and more commonly Room temperature were stored for 24 hours. This was followed by a 15-hour heat treatment at 100 ⁰ C in likewise H ₂ O vapor saturated atmosphere. After drying at 110 ^° C., the samples prepared in this way showed the following characteristic values up to mass constancy:

I Sample Il Compressive strength in MPa 74.0 ¹ 103.0 Compressive strength in MPa after fire at 115O ⁰ C and 4-hour hold time 42.9 59.1 Compressive strength in MPa after fire at PK175 in a high temperature tunnel oven 52.8 53.6 Change in length in% after fire at 150 ⁰ C ± 0.1 ± 0.1 after fire at PK175 ± 0.1 ± 0.1 Pressure fire resistant at 2kp / cm ² Load, To.iin ⁰ C greater than 1700 greater than 1700 Thermal shock resistance, Number of deterrents greater than 25 greater than 25 Thermal shock resistance, Number of deterrents after the fire at PK175 22 not determined

1. A process for the preparation of heat-resistant and refractory materials, characterized in that silicate and / or non-silicate raw materials in known grain composition in a mixing unit with water or water-sulfite waste liquor mixture up to 15 wt .-% wetted, with a heat treatment cement based on aluminas added as a binder, homogenized, pressed on known shaping devices into molds and then heat treated.

2. The method according to item 1, characterized in that as silicate raw materials Rohsrhamotte, sintered Tonlaugungsrückstaenst, Sintermullit and industrial seizure ProJukte such. B. high-alumina secondary raw materials find use.

3. The method according to item!, Characterized in that find as non-silicate raw materials white and / or brown coal, sintered clay and / or sintered spinel use.

4. The method according to item 1, characterized in that the binder clays clays, kaolins and / or highly active Ci-Al ₂ Oa mixed with the addition of sulfite powder or homogenized by a Mischmahlung with the binder who Jen.

Process according to item 1, characterized in that the clay, kaolin or the highly active clay in the binder is partly or completely replaced by glass powder, MgO.Al ₂ O ₃ or ZrO ₂ -containing by-products.

6. The method according to item!, Characterized in that the heat treatment takes place over several hours in a saturated steam atmosphere up to 100 ⁰ C.

Field of application of the invention

The invention relates to a process for the production of heat-resistant and refractory materials for pyrotechnic systems.

Characteristic of the known solutions

It is known to produce refractory materials from natural resources, where z. As clays and / or kaolins are fired to Rohschamotte, which in turn are involved with a corresponding proportion of the processed natural raw material and then burned in a renewed firing process to refractory materials.

Also known is the production of refractory materials, where in the electric furnace produced by the melt process raw materials such as white and / or brown coal are added by binding clay and / or other substances and then fired in a firing process to refractory materials.

Furthermore, it is known that heat-resistant building materials, consisting of industrial sources such. As chamotte fracture and conventional Portland cement, are used as a binder for large prefabricated parts, which are used instead of conventional refractory small-scale building materials.

It is also known that aluminate binders are used in conjunction with other additives to achieve higher application temperatures in the finished parts. Thus, a concrete material for high use temperatures consists of e.g.

20% by weight of aluminative binder with 70% Al ₂ O ₃ and 80% by mass of white alumina with greater than 99% Al ₂ O ₃ .

A concrete produced according to this composition at a WZF of 0.6 is characterized by the following parameters:

- permissible application temperature 1700 ° C

- Al ₂ O ₃ content rd.93%

- content of CaO rd.5,5%

- Dye resistance, t _o , 6 1400-1500 "C

- Compressive strength after fire at application temperature 8-12MPa

- Compressive strength after normal, 14-day storage greater than 20 MPa

- irreversible change in length + 0.8 to + 1.5%.

It is also known that with Portland or alumina cement using various aggregates on so-called concrete pavers molded blocks can be produced, but which do not differ in principle in many property characteristics of the finished parts.

A disadvantage of the known material solutions and methods is once that the product fire conventional refractory materials depending on the firing temperature z. B. a fuel oil consumption of 83-300 kg / t refractory material is recorded. On the other hand, it is disadvantageous that in terms of geometry quite generally questions of geometry, availability, completion possibility, flexibility in delivery, structure and structure formation and thus influence on the thermomechanical properties and strength education after thermal stress at application temperatures and in the critical temperature range are pending.

Purpose of the invention

The purpose of the invention is to completely eliminate these disadvantages.

The invention has for its object to provide a new method for the production of heat-resistant and refractory materials.

According to the invention, this object is achieved in that silicate and / or non-silicate raw materials wetted in known mixing composition in a mixing unit with water or water-sulfite liquor mixture up to 15Ma .-%, mixed with a heat treatment cement aui aluminate base as a binder, homogenized, known Forming devices pressed into molds and then heat treated. The advantages of such a procedural solution are that once the modern Montagi construction with species-specific, but in the format but strongly divergent materials can be useful supplemented and on the other hand for this conventional conventional in the refractory stone formats no energy-consuming burning process is required. Furthermore, the advantages consist in that the texture is formed by the use of compression compaction at specific pressures greater than 10 MPa as in the classic refractory materials, which leads to significantly improved thermomechanical properties at temperatures in the critical temperature range and classification temperature compared to the heat-resistant and refractory precast concrete , This in turn results in improved wear resistance during abrasion.

The invention will be explained in more detail in the embodiments.

Embodiment 1

A CA / CA ₂ cement with approx. 70% Al ₂ O ₃ is homogenized with the addition of 20% dried kaolin and 0.5% sulfite powder in a mixing drum in the presence of large-volume sintered corundum grinding media. It is desirable that the heat treatment cement thus produced passes without residue, the 90-micron sieve. The leaning agent, in this case Kaolinrohschamotte in the grain size 0 to 1 and 1 to 3mm, is moistened with a water-sulfite liquor mixture, dilution 10: 1. Thereafter, in the suitable mixing unit, the addition of the binder based on a heat treatment cement and the final mixing of the Preßgemenges, the Preßgemenge with the composition of based on dried substance -

20% by weight of heat treatment cement 1400 (consisting of CA / CA ₂ -zomentum, kaolin and sulphite powder), 40% by mass of kaolin raw ash 0 to 1 mm and 40% by mass of kaolin raw ash 1 to 8 mm

is to be pre-pressed within 15 hours to the desired stones of different geometry. This is followed by an intermediate storage in a closed room with H ₂ O vapor-saturated atmosphere and usual room temperatures up to 24 hours. Then db several hours of heat treatment to 100 ⁰ C and also saturated with water vapor atmosphere. After, for example, 15stündigor heat treatment and subsequent drying to constant mass the suitable for application temperatures up to 1400 ⁰ C. Materials characterized by the following characteristics.

Compressive strength in MPa 43.2

Compressive strength in MPa after fire

with 15O ⁰ C and 4-hour hold time 32.3

Change in length after firing 15O ⁰ C

and 4-hour hold time in% -0.1

Length change after fire at 1 400 ° C

and 4-hour hold time in% -0.2

Pressure fire resistance at

2 kp / cm ² load To.6 in ⁰ C 1480

Temperaturwechselboständigkeit,

Number of deterrents, η 2Γ <

Embodiment 2

For a high-temperature material, in which fused alumina is used as a leaning agent, the CA / CA ₂ cement with approx. 70% AI ₂ O ₃ to a heat treatment cement with approx. 85% Al ₂ O _{3 are} reacted.

This is necessary in order to eliminate the later formation of CAO in view of the re-growth of the building material at high temperatures and on the other hand to impart high edge strength to freshly pressed stone. The above is achieved by the addition of a ground in the presence of sulfite powder or activated alumina.

For the exemplary embodiment, calcined alumina was ground to TGL 7750 with the addition of 1% sulphite powder so that the residue at 40pm max. 8%; The residue at 63 and 90pm was 0%. (This special clay was mixed with the CA / CA ₂ cement 1: 1.) Of this high alumina thermal treatment cement 20Ma .-% were used as a binder, ie, in principle, the cement content was only 10Ma .-%.

After the composition dor two pressing amount of

I Il Hot-rolling cement 1 700 20Ma .-% 20Ma .-% (consisting of CA / CA ₂ cement, highly active clay and sulphite powder) White corundum, grain size 00 WS 10ma .-% - White corundum, grain size 25 10ma .-% 20Ma .-% White corundum, grit 63 20Ma .-% 20Ma .-% Woelfkorund, grain size 160 40ma .-% 40ma .-%

and per kg of 55 ml water-sulfite waste liquor mixture, 4: 1 diluted, as Preßgemengefeuchte were prepared after conditioning of the Preßgemenges at a pressure of 100MPa body after shaping in a closed container in saturated H ₂ O vapor atmosphere and more commonly Room temperature were stored for 24 hours. This was followed by a 1 Bstündige heat treatment at 100 ⁰ C in likewise H ₂ O vapor saturated atmosphere. The samples thus prepared showed the following characteristics after drying at 110 ^° C. to constant mass:

I Sample Il Compressive strength in MPa 74.0 103.0 Compressive strength in MPa after fire at 115O ⁰ C and 4-hour hold time 59.1 Compressive strength in MPa after fire at PK175 in a high temperature tunnel oven 52.8 53.6 Change in length in% after fire, 15O ⁰ C ± 0.1 ± 0.1 after fire at PK175 ± 0.1 ± 0.1 Pressure fire resistant at 2 kp / cm ^l Load, T _0tt in ^o C greater than 1700 greater than 1700 Thermal shock resistance, Number of deterrents greater than 25 greater than 25 Temperaturwechselboständigkeit, Number of deterrents after the fire at PK175 22 not determined

Claims (6)

1. A process for the production of heat-resistant and refractory materials, characterized in that silicate and / or non-silicate raw materials in a known grain composition in a mixing unit with water or water-sulfite waste liquor mixture up to 15 wt .-% wetted, with a heat treatment cement alumlnatischer basis added as a binder, homogenized, pressed on known shaping devices into molds and then heat treated. 2. The method according to item 1, characterized in that the silicate raw materials raw chamotte, sintered Ton laugungs residues, sintered mullite and industrial seizure products such. B. high-alumina secondary raw materials find use. 3. The method according to item 1, characterized in that as non-silicate raw materials white and / or brown coal, sintered clay and / or sintered spinel are used. 4. The method according to item 1, characterized in that the binder clays, kaolins and / or highly active 0.-Al ₂ O _{3 are added} with the addition of sulfite powder or homogenized via a Mischmahlung with the binder. 5. The method according to item 1, characterized in that the clay, kaolin or the highly active clay in the binder is partially or completely replaced by glass powder, MgO · Al ₂ O ₃ or ZrO ₂ -containing seizure products. 6. The method according to item 1, characterized in that the heat treatment takes place over several hours in a saturated steam atmosphere up to 100 ⁰ C. Field of application of the invention The invention relates to a process for the production of heat-resistant and refractory materials for pyrotechnic systems. Characteristic of known solutions It is known to produce refractory building materials from natural raw materials where e.g. Clays and / or kaolins too Raw chamotte are fired, which in turn with a corresponding proportion of the processed natural raw material be integrated and then burned in a renewed firing process to refractory materials. Also known is the production of refractory materials, where produced in the electric furnace by the melt process Raw materials such as white and / or brown ore mixed with Bindetons and / or other substances and then at a Burning process are burned to refractory materials. Furthermore, it is known that hiizebestäiidige building materials consisting of industrial sources such. B. chamotte and conventional Portland cement, be used as a binder for large prefabricated parts, the parts of conventional refractory small-scale building materials use. It is also known that to achieve higher application temperatures in the finished parts aluminate binder in Be used in conjunction with other aggregates. So a concrete material for high application temperatures ausz.B. 20% by weight of aluminative binder with 70% Al ₂ O ₃ and
80% by mass of white corundum with greater than 99% Al ₂ O ₃ . A concrete produced according to this composition at a WZF of 0.6 is characterized by the following parameters: - Permissible application temperature 1700 ° C - Al ₂ O ₃ content rd.93% - Salary to Cao rd.5,5% - Pressure fire resistance, to.e 1400-1500 ⁰ C - Compressive strength after fire at application temperature 8-12MPa - Compressive strength after normal, 14-day storage greater than 20 MPa - irreversible change in length + 0.8 to + 1.5%. It is also known that with Portland or alumina cement using various aggregates on so-called concrete pavers molded blocks can be produced, but which do not differ in principle in many property characteristics of the finished parts. A disadvantage of the known material solutions and methods is once that the product firing of conventional refractory materials depending on the firing temperature, e.g. a fuel oil consumption of 83-300 kg / t refractory material is recorded. On the other hand, it is disadvantageous that the geometry of concrete, availability, completion options, flexibility in delivery, structure and structure formation and thus influence on the thermomechanical properties and strength training after thermal stress at application temperatures and in the critical temperature range are pending in the concretes.