AT509011B1 - MINERAL FOAM - Google Patents

Description

Austrian Patent Office AT 509 011 B1 2011-10-15

Description: The invention relates to a porous mineral foam comprising a hydraulically setting component and a foam component, wherein the hydraulically setting component is formed by a formulation for producing a self-curing mineral foam, comprising a hydraulically setting and a pozzolanic setting binder and a sulfate the hydraulically setting binder is formed by a sulfate-aluminate cement comprising a sulfate component and an aluminum component contained in a proportion of at least 50 parts by weight, a component having a component body, and a method of producing a self-curing mineral foam after the powdery component to prepare a formulation in a first mixing section, they are mixed together to give a mixture, and water is added to this mixture to form a slurry, wherein the slurry is introduced into a second mixing section e foam component is added and mixed into the slurry and then the mineral foam is hardened.

Mineral foams are already known from the prior art. For example, e.g. EP 0 628 523 A1 discloses a process for producing a thermal insulation material of quartz powder with a BET specific surface area of at least about 3 m 2 / g, hydrated lime, water, foam and a rapid cement containing reactive aluminates, in which the thermal insulation material has a bulk density of less than 250 kg / m3. From the raw materials, a pourable raw mixture is produced, which is poured into molds. The crude mixture becomes substantially stoichiometric depending on the total surface area of the solids at a weight ratio of water / solids (without foam) of at least about 1.25 to about 1.85 and a substantially complete conversion of the silica flour and the reactive aluminates Amount of hydrated lime having a BET surface area of at least about 15 m2 / g. The ingots cast in molds are removed from the mold after sufficient solidification to a mold bottom and autoclaved on the mold bottom. The foam used is a surfactant or a protein foam.

US 2006/0075932 A1 describes a formulation for a foamed cement material comprising at least one hydraulic binder, microparticles having a particle size between 0.1 and 30 pm and in an amount between 15 and 50 mass% in relation to the mass hydraulic binder, mineral particles having a particle size between 1 and 500 pm and in a proportion of between 10 and 35% by mass relative to the mass of the hydraulic binder, the proportion of mineral particles being less than the proportion of microparticles, a water-soluble polymer Diluent in a proportion of between 0.1 and 8% by mass with respect to the mass of the hydraulic binder, with a maximum of 40% by mass of water in relation to the mass of the hydraulic binder, and a foaming agent in a proportion between 0.1 and 10 mass .-% in relation to the mass of the hydraulic binder (summary). The foamed cement material is used for lining boreholes.

EP 0 816 303 A1 describes a process for the production of a lightweight, open-pore mineral insulation board with a bulk density of less than 130 kg / m 3, comprising the following steps: a) preparing a water / solid suspension by intensive mixing the following raw materials in an intensive mixer with rotating mixing container and high speed rotary mixing tool using water and, based on the total solids content, 40 to 48 M .-% (mass percent) of quartz powder with a BET specific surface area of at least 2 , 5 m 2 / g, 15 to 20 M .-% hydrated lime with a specific surface area of at least 15 m 2 / g, 25 to 35 M% cement, 0.3 to 0.5 M .-% hydrophobizing agent, balance additives, wherein the ratio of cement to hydrated lime is 1.5 to 2.3: 1, the proportion of binder is in the range of 45 to 52% by mass and the suspension has a water / solids factor (without foam) of 0.7 to 1.2, b) providing a s Foam made of water, air and a pore-forming agent with a 1/15 Austrian Patent Office AT 509 011 B1 2011-10-15

Crude density of 40 to 50 kg / m3, c) introduction of the foam into the water / solid suspension still in the mixing container in intensive mixer and mixing the foam at low speed of the mixing tool in a maximum of 120 seconds, [ 0008] d) pouring the raw mixture into at least one mold, [0009] e) allowing the crude mixture to stiffen to a still plastic block having sufficient green state resistance, f) lifting the plastic block from the mold bottom by means of vacuum, g) cutting the Blockes by means of wires in individual insulation boards and h) curing the insulation boards in an autoclave.

GB 2 360 769 A discloses a hydraulic binder for forming a non-efflorescent cementitious body comprising a source of active silica, (i) a source of calcium aluminate, (ii) a source of calcium silicate, and (iii ) a source of sulfate, wherein the binder comprises 10% to 49% by weight of the source of active silica (based on total cementitious dry mix), and the balance based on the total weight of (i), (ii) and (iii) comprises: (i) from 40% to 90% by weight of the source of calcium aluminate selected from calcium aluminate cement or clinker and calcium sulfoaluminate cement or clinker, the source of calcium aluminate being at least 25% alumina or a C (A) 5 wt% to 55 wt% Portland cement or clinker as the source of calcium silicate, and (iii) 3 wt% to 50 wt% of the source of Sulphate, of which at least 25% is S03.

US 2005/0252419 A1 describes a composite mineral foam made of reactive components. The reactive components can be obtained by reaction of metal oxides, phosphates and residues. To this mixture is added a reactive foaming agent and / or a latex polymer. The composite has a density of between 0.35 to 2.25 g / cm3, and may i.a. used for blocks or plates.

A roof tile is known from EP 1 826 332 A1 comprising a coated substrate wherein the coating is made of a mixture comprising a hydraulic binder in a proportion of at least 60 wt .-% of a Calzuimaluminatquelle and not more than 1 wt. % Sulphate.

WO 2008/130107 A1 describes a rapid-release foam produced from an aqueous solution of water and a foaming agent, cement, silicon dioxide, ceramic powder and an accelerator.

Object of the present invention is to provide a self-curing mineral foam, which has a dry weight of at most 300 kg / m3.

This object of the invention is achieved independently by the aforementioned mineral foam in which the sulfate is selected from a group comprising calcium sulfate as anhydrite, as dihydrate, as α-hemihydrate, as ß-hemihydrate, magnesium sulfate, sodium sulfate, and mixtures thereof , wherein the proportion of the sulfate is between 5 parts by weight and 25 parts by weight, by a component comprising the mineral foam, and by the aforementioned method in which the formulation is combined as stated in claims 1 to 18 and the mineral foam is hardened without autoclaving ,

The advantage here is that the mineral foam can be produced without required autoclaving, whereby the process can be simplified and costs can be reduced. The use of said hydraulically setting binder also has the advantage that the mineral foam does not or does not substantially shrink during hardening. It is thus u.a. achieved that provided with the mineral foam components such. With this at least partially filled hollow brick, are easier to produce, by not taking into account a Schwundmaß must. It is thus the degree of filling of such devices can be improved, whereby the thermal insulation can be improved in total. In addition, it can be used to achieve a mineral foam that also has fire protection properties up to approx. 1150 ° C.

Preferably, the proportion of the sulfate aluminate cement in the formulation is at least 60 parts by weight, in particular at least 70 parts by weight, whereby the properties of the mineral foam can be further improved.

The statement that the sulphate-aluminate cement contains a sulphate component and an aluminum component does not necessarily mean in the context of the invention that these are discernible phases of the cement, but merely clarifies that in the sulphate-aluminate cement. Cement S04 or S03und aluminum are included.

Preferably, the sulfate component is selected from a group comprising calcium sulfate, α- or ß-hemihydrate or dihydrate of calcium sulfate, anhydrite, sodium sulfate, iron (II) sulfate, magnesium sulfate and mixtures thereof. Hydrate phases are thereby produced during the hardening of the mineral foam, which undergo a phase transformation over time, the strength increasing.

The aluminum component is preferably selected from a group comprising alumina (Al 2 O 3), aluminum hydroxides, aluminum silicates, aluminates and mixtures thereof. It can thus be positively influenced the solidification behavior and the setting time.

The ratio of the sulfate component to the aluminum component may be selected according to an embodiment of a range with a lower limit of 4:10 and an upper limit of 20:30. It is thus achieved that the setting time of the slurry does not take so long that there is a risk that the added foam collapses and thus the porosity of the mineral foam is reduced. It is thus simplified by keeping the ratio of the two components in this area, the processing.

In particular, to further improve this behavior, the ratio of the sulfate component to the aluminum component may be selected from a range having a lower limit of 6:12 and an upper limit of 13:22, preferably a lower limit range of 10:18 and an upper limit of 12:24.

To improve the mechanical properties, the formulation may additionally contain SiO 2 particles in a proportion of not more than 10 parts by weight. However, the proportion of SiO 2 particles is preferably at most 7.5 parts by weight.

According to another embodiment, the formulation contains special SiO 2 particles fumed in the form of so-called silica. This is a reactive SiO 2 that can improve the fire resistance performance of the mineral foam, by consuming energy for reactions that makes SiO 2 a "cooling" catalyst. Has effect. In particular, carbon-free SiO 2 particles with a purity of at least 97% are used.

In one embodiment, it is provided that the SiO 2 particles have a BET surface area between 5 m 2 / g and 35 m 2 / g in order to increase the reactivity. Preferably, the SiO 2 particles have a particle size of at most 45 pm, wherein in particular the proportion of coarse grain is limited to a maximum of 2% and the remainder of the SiO 2 particles have a particle size of not more than 1 μm, preferably not more than 0.3 μm.

Preferably, the SiO 2 particles have a BET surface area between 10 m 2 / g and 25 m 2 / g, in particular between 16 m 2 / g and 20 m 2 / g.

The formulation may further contain at least one so-called high-conductivity liquefier to influence the rheological behavior of the slurry formed from the formulation, provided that the addition of silica fumed, which also has a liquefying effect due to the spherical shape of the particles, not alone is sufficient for this purpose, wherein the proportion is limited to a maximum of 3 parts by weight. In particular, when silica-fumed is included in the formulation, the proportion of the high-performance plasticizer is limited to a maximum of 0.5 part by weight, preferably a maximum of 0.3 part by weight.

Preferably, the high-performance liquefier is a polycarboxylate ether in order to be able to reduce the water content of the slurry so that less water is available for setting and thus the desired phases are formed more reliably.

It is further possible that the formulation for stabilizing the slurry and thus for better processability of the slurry at least one thickener is added in a proportion of not more than 0.5 parts by weight. The thickener is preferably added in a proportion of not more than 0.25 parts by weight, in particular not more than 0.02 parts by weight.

Preferably, the thickener is selected from a group comprising hydroxymethylpropylcellulose, methylhydroxyethylcellulose and mixtures thereof, since it has been found in the context of the tests carried out for the invention that these thickeners with respect to processing better properties, such as. the rheology, the dispersion of the solids, or the water requirement and the water retention capacity.

In view of the processability of the slurry has also been found that improvements occur when the proportion of thickener is not more than 70% of the proportion of high-performance liquefier.

It is further possible that the formulation fibers in a proportion of not more than 3 parts by weight, in particular not more than 1 parts by weight, preferably 0.3 parts by weight, are added to improve the flexural strength of the mineral foam. But it can also be used to stabilize the foam component. In addition, e.g. Cellulose fibers store water, which is needed in the setting process, this physically "bound". Water is better controlled with respect to the hardening of the mineral foam. Cellulose fibers can also be used as thickeners.

Preferably, the fibers have a maximum length of 50 mm, in particular a maximum of 30 mm, and are in particular selected from a group comprising cellulose fibers, basalt fibers, glass fibers, in particular alkali-resistant glass fibers, polypropylene fibers, and mixtures thereof.

Fibers of greater length, so for example with a length between 3 mm and 50 mm, in particular between 3 mm and 30 mm, preferably between 3 mm and 12 mm, wherein the diameter is preferably between 13 pm and 25 pm, preferably between 13 pm and 18 μm, are added mainly when bending tensile strength is to be increased. Fibers up to a length of 0.1 mm, preferably up to 30 pm, and in particular a diameter of up to 2 pm, preferably up to 1.5 pm, are preferably added for theological reasons.

The formulation may be added to improve the rheology at least one processing aid from a group comprising an alkali metal carbonates, alkali metal sulfates, fruit acids, for example as a retarder.

In order to reduce the proportion of sorption moisture in the finished mineral foam, it can be provided that at least one hydrophobizing agent is added, in particular for the mass hydrophobization of the formulation. The proportion of the hydrophobizing agent in the formulation may be up to 3 parts by weight, preferably up to 1 part by weight.

According to another embodiment of the formulation, it may be provided that it is free from added particles, i. is filler-free, so contains no non-reactive constituents, whereby the density of the mineral foam could be further reduced.

Preferably, the foam component is formed by a protein foam and / or a surfactant. It can thus be better controlled the foaming behavior than in the method of direct foaming with a blowing agent. In particular, the pore size and the pore distribution can be influenced, and thus the heat conductivity or the sound absorption capacity of the mineral foam can be better adjusted. The proportion of the foam component per m3 of slurry is preferably between 30 kg / m3 and 70 kg / m3, in particular between 40 kg / m3 and 60 kg / m3 so that an improvement in the properties of the mineral foam could be observed.

To stabilize the foam during mixing into the slurry from the formulation with water, a surfactant can be added to the foam component.

According to a preferred embodiment, the mineral foam has a pore content of at least 70%, in particular between 80% and 95%. Due to this high proportion of pores, not only can the insulation behavior per se be improved, but it also makes it possible to achieve a lower volume weight of the mineral foam.

In this case, the pores preferably have a diameter of at most 0.5 mm, in particular a maximum of 0.25 mm or a maximum of 0.1 mm, on the one hand to achieve a positive insulating behavior and on the other hand to the mechanical stability of the finished mineral foam improve.

The foam component may also include air entraining agents, e.g. Alkyl polyglycol ethers, alkyl sulfates or sulfonates, i.a. to improve the stability of the foam.

According to one embodiment of the method is provided that the foam component is added to the slurry in a foam generator with water and optionally processing aids prior to adding, whereby their processability, in particular the stability of the foam during mixing with the slurry, can be improved , It can be arranged in the device for foaming the foam component, a foam generator, in which a protein mixed with water with a gas, in particular air, is foamed.

For a better understanding of the invention, this will be explained in more detail with reference to the following figure.

It shows in a schematically simplified representation: FIG. 1 shows an apparatus for producing a self-hardening mineral foam. [0049] FIG.

By way of introduction, it should be noted that the location information chosen in the description, such top, bottom, side, etc. related to the immediately described and illustrated figure and are to be transferred to the new situation mutatis mutandis when a change in position.

FIG. 1 shows a device 1 for producing a self-curing, mineral foam 2.

One of the most significant advantages of the invention is that the mineral foam 2 need not be autoclaved, as is known in the art. For this purpose, the device 1 in the core of the invention, a first mixing section 3 and one of these downstream in the direction of production, second mixing section 4. In the first mixing section 3 of powdered components of a formulation for producing the mineral foam 2, which can be kept in stock in storage containers 5, and which are fed via a conveyor 6, such as a screw conveyor, the first mixing section 3, with the addition of water accordingly Arrow 7, a so-called slurry, so a mixture of the solid components and water produced. Normally, normal tap water is used as water, it being understood that it is also possible to use distilled water. Optionally, further additives for mixing with the pulverulent components in the first mixing section 3 can be applied, as indicated by a dashed arrow 8 in Fig. 1, wherein at least some of the additives can also be added in liquid or dispersed form.

It is possible that the mixing of the pulverulent constituents takes place before the addition of the water according to arrow 7, that is, added to the main components of the formulation for producing the mineral foam 2 already these auxiliaries or processing aids and optionally these powdered components Formulation 5/15 Austrian Patent Office AT 509 011 B1 2011-10-15 can be premixed.

The mixing section 3 is designed as a paddle mixer or plow blade mixer, wherein also other types of mixers, such as. Free fall mixer, can be used. However, the former mixer types have the advantage that less water has to be added - the goal is to use as little water as possible - and that the energy consumption per m3 of slurry is relatively low. In addition, the risk of gluing the mixer can be reduced by these rounded shapes. In particular, this mixing section 3 may comprise mixing elements 9, which are arranged offset in the radial direction on a mixing path shaft 10. It can be arranged in the mixing section 3 between 2 and 20 mixing elements 9.

This slurry is subsequently added with a protein foam and / or a surfactant foam as foam component, which is produced in a foam generator 11. Thus, the mineral foam 2 according to the invention is not foamed directly but the pore formation of the mineral foam 2 by the addition of a separate foam. The foam component used for this purpose is a protein foam and / or a surfactant foam. As protein 12, which can be kept in stock in a corresponding storage container 13, an animal or a vegetable protein or mixtures thereof is used. In particular, a keratin, preferably a hydrolyzed keratin, or a soy-based protein, which is preferably alkali-resistant, is used as protein 12. The protein can be used in an amount of up to 5 parts by weight.

This protein 12 is again water, in particular distilled or purified water, added according to arrow 14 and is generated in the foam generator 11 by the injection of air according to arrow 15 of the protein foam.

As shown in phantom in the region of the foam generator 11 in Fig. 1, this foam component may also contain processing aids, e.g. be added from a reservoir 16, wherein it is also possible that, in the event that several processing aids are added, a mixing of these auxiliaries takes place beforehand.

In general, it should be noted that these processing aids for the addition of the foam component can be added in powder form or in dissolved or dispersed form.

The finished foam component is added in the sequence according to arrow 17 from the first mixing section 3 derived slurry according to arrow 18, wherein the addition takes place in the second mixing section 4 or preferably before the second mixing section 4. For this purpose, this mixing section 4 can be a conveying device 19, e.g. a screw conveyor, upstream, in which case it is possible for the time being the foam is introduced into the conveyor 19 so that it is at least approximately completely filled with this, and then the slurry is added to the foam, in particular stepwise, also a plurality of filling openings for the slurry may be present in the conveying device 19. However, it is possible deviating or in addition to the fact that the slurry is added to the foam only in the second mixing section 4.

The second mixing section 4 is designed in particular as a paddle, screw, spiral mixer or static mixer or in the form of combinations thereof.

In the context of the invention there is the possibility that the two mixing sections 3, 4 are combined in a single mixer, wherein they are also separated from each other in this case, that are formed one behind the other in this mixer.

There is also the possibility that the first and / or second mixing section 3, 4 consist of a separate conveying device 6 or 19 and a separate mixer, the separation can only look so that they have separate drives to To allow different speeds and thus a better mixing result with the least possible use of energy.

As a result, the finished mixture of the slurry and the foam component from the second mixing section 4 is withdrawn via a corresponding conveyor 20 and this mixture can be filled into a corresponding mold in order to allow self-curing of the mineral foam 2 by the correspondingly proceeding, chemical reactions.

It should be noted that the mineral foam 2 according to the invention, for example in sheet form, for subsequent application to be insulated structural parts, such as walls, may be formed, it is also possible that with the mixture of components, in particular hollow bricks, be at least partially filled, so so in itself insulated components, for example, provided with a thermal insulation bricks or stones can be produced. But there are also other forms and uses of mineral foam 2 possible, for example as fire protection material, for which higher space weights of the mineral foam 2 are advantageous as granules for fillings or fillings, as a building material in stone form, in particular as a brick, as a soundproofing material, especially in Combination with other materials, as an addition to a mortar, as a plaster base, generally as a building material, for the air conditioning of rooms, in or as chimney stone (s), etc.

Although not shown in Fig. 1, it is within the scope of the invention, the possibility that appropriate control and / or control organs and / or measuring organs within the device 1 are present and can these control and / or control organs and / or measuring organs Of course also computer-assisted operated.

There is also the possibility that for the production of the foam, instead of air, other gases, such as e.g. N2, C02, etc., are used. Furthermore, there is the possibility that the protein, in particular alkaline, blowing agent is added, so that it can be dispensed with the addition of a separate gas for the foaming of the protein or the amount of gas can be reduced.

It should be noted at this point that the selected number of mixing elements 9 in the first mixing section 3, as stated above, has advantages with regard to the product properties of the mineral foam 2. Although it is also possible to produce a mineral foam 2, ie a slurry, with a smaller or higher number of mixing rods 9, it has been found within the framework of testing the invention that the product properties of the mineral foam 2 have a number of mixing elements 9 from the stated range are improved. It should be noted that the number of mixing elements 9 is related to a certain size of the device 1, that is, to a certain volume output of mineral foam 2, which is up to 50 m3 / h. It is therefore possible, although not yet tested, that a number deviating from the specified number of mixing elements 9 is advantageous in the case of another design of the system 1.

Furthermore, it was found within the scope of the invention that a peripheral speed selected from a range with a lower limit of 4 m / s, in particular 5.5 m / s, and an upper limit of 12 m / s, in particular 11 m / s, with which the mixing path shaft 10 of the mixing section 3 is operated, for the specified production volume also has advantages in terms of product properties of the mineral foam 2. In particular, it is advantageous if a number of 16 mixing elements 9 are arranged at a circumferential speed of 6 m / s and a number of 4 mixing elements 9 at a peripheral speed of 10 m / s of the mixing path shaft 10, these figures as the lower and upper limit a range for the number of mixing elements 9 with respect to the peripheral speed of the mixing path shaft 10 are to be understood.

It should be noted again in this context that, in particular for the first mixing section 3, but also for the second mixing section 4, combinations of different types of mixing devices 9 can be used, for example, 5 stator bars and 4 paddle bars as a rotor. In general, a combination of stator and rotor bars in the mixing sections 3, 4 can be used.

For a flow rate between 5 kg / min, in particular 15 kg / min, and 50 kg / min, in particular 35 kg / min, of the pulverulent constituents for the production of the slurry, a volume of water between 150 l / h, in particular 300 l / h and 1000 l / h, in particular 500 l / h, the first mixing section 3 is supplied. Again, an interaction with the number of mixing elements 9 in the first mixing section 3 with respect to the product properties of the mineral foam 2 could be observed. It is particularly advantageous if, in the case of a number of 6 mixing devices 9, a volume flow of 250 l / h of water and, in the case of a number of 18 mixing elements 9, a volume flow of 800 l / h of water are added to the pulverulent constituents of the formulation for the preparation of the slurry, Again, these figures are to be understood as the lower and upper limit of a range for the number of mixing elements 9 with respect to the water flow rate.

For the addition of the water to the powdery components in the first mixing section 3, it is advantageous if the water is distributed over several areas of the mixing section 3, in particular via spray nozzles. For example, can be arranged distributed over the circumference of the first mixing section 3 between 2 and 10, in particular between 3 and 6, spray nozzles.

For a flow rate between 7 kg / min and 40 kg / min slurry, a volume flow of 80 l / min to 140 l / min foam component from the foam generator 11 in the second mixing section 4 is applied, for example, for 25 kg / min slurry 100 l / min foam component, so that the foam component, for example, assumes a proportion of between 40 kg and 60 kg per m3 of wet slurry in the slurry / foam mixture. Preferably, the foam component has a density selected from a range having a lower limit of 35 kg / m 3 and an upper limit of 60 kg / m 3.

The peripheral speed with which the second mixing section 4 is operated is preferably smaller than that of the first mixing section 3 in the above-described production volume and with regard to the volume flow of added foam component. The mixing elements of the second mixing section 4 are arranged in this case in that a homogeneous mixing takes place within the mixing section 4 between the slurry and the foam component and the foam component is gently mixed with the slurry.

It can be made with the device 1 according to the invention and the method according to the invention, a mineral foam 2, which has a density of max. 300 kg / m3, in particular a density between 100 kg / m3 and 250 kg / m3. In this case, this specification refers to the completely dried mineral foam 2. The density of the volume can also be adjusted, for example, via the densities of the slurry and the foam component.

The formulation from which the slurry is prepared in the first mixing section 3, consists in the simplest case of a hydraulically setting binder, a pozzolanic setting binder and a sulfate, wherein the hydraulically setting binder by a sulfate aluminate cement (a Sulfo-aluminate cement) comprising a sulfate component and an aluminate component and contained in a proportion of at least 50 parts by weight in the powdered formulation. The proportion by weight of the sulfate-aluminate cement in the formulation is preferably at least 60 parts by weight, in particular at least 70 parts by weight. A preferred range in which the sulfate-aluminate cement is incorporated in the formulation is between 65 parts by weight and 75 parts by weight.

The pozzolanic bonding binder may be a natural or, in particular, a synthetic pozzolan, for example, trass, blast furnace slag, LD slag, metakaolin. Basalt, or mixtures thereof may be formed. The proportion of the pozzolanic binder in the formulation is up to 40 parts by weight. A preferred range of pozzolanic bonding binder is between 10 parts by weight and 30 parts by weight.

As sulfate calcium sulfate is preferably used as anhydrite, dihydrate and / or as a-hemihydrate Austrian Patent Office AT 509 011 B1 2011-10-15, but it can also other sulfates, such as a ß-hemihydrate of calcium sulfate as well as magnesium sulfate or sodium sulfate. Optionally, mixtures and derivatives thereof are also replaceable. The proportion of sulfate in the formulation is between 5 parts by weight and 25 parts by weight. A preferred range is between 10 parts by weight and 15 parts by weight. The added sulfate functions inter alia as a grinding aid for the formulation, in particular if it is ground before being fed to the first mixing section 3, or as an accelerator. It also improves the green strength of the slurry / foam mixture.

The sulfate component of the sulfate aluminate cement is preferably selected from a group comprising calcium sulfate, α- or β-hemihydrate or dihydrate of calcium sulfate, anhydrite, sodium sulfate, iron (II) sulfate, magnesium sulfate, and mixtures and derivatives thereof , The proportion of the sulfate component in the sulfate aluminate cement is up to 20 parts by weight.

The aluminum component of the sulphate-aluminum cement can be selected from a group comprising aluminum oxide, aluminum hydroxides, aluminum silicates, aluminates and mixtures and derivatives thereof. The proportion of the aluminum component in the sulfate-aluminate cement is preferably up to 30 parts by weight.

In the course of the test carried out for the invention, it was found that a ratio of the sulfate component to the aluminate component selected from a range with a lower limit of 4:10 and an upper limit of 20:30 had advantageous effects with regard to the thermal insulation behavior of the mineral foam 2 has. By adhering to these conditions, the green strength of the not yet hardened mineral foam 2 could be improved, whereby the processing of the mineral foam 2 can be simplified.

The pulverulent constituents of the formulation, ie the hydraulically setting binder, the pozzolanically setting binder and the sulfate, preferably have a particle size of up to 40 μm and a maximum of 17% larger particles in the main amount. By adhering to this freeness of the powdered main components of the formulation, the production of the slurry can be improved, in particular it can also be positively influenced on the porosity and the volume fraction of the pores in the mineral foam 2.

In addition to these main constituents of the formulation, that is to say the hydraulically setting binder, the pozzolanically setting binder, which is used, inter alia, as a substitute for a proportion of the sulfate-aluminate cement, as well as of the sulfate, is within the scope of the invention the possibility that this formulation further, especially powdery, additives and excipients are added, but in the preferred embodiment, this formulation contains no non-reactive fillers, so all the components are reactive.

As an additional ingredient, the formulation may contain SiO 2 particles in a proportion of not more than 10 parts by weight. In particular, a so-called silca fumed is used as SiO 2, wherein in the preferred embodiment this SiO 2 has a BET surface area between 10 m 2 / g, preferably 16 m 2 / g, and 30 m 2 / g, preferably 20 m 2 / g.

The pozzolanic binder preferably has a Blaine value of between 3000, in particular 4000, and 6000, in particular 5400.

The sulfate-aluminate cement preferably has a Blaine value between 4000, in particular 5000, and 7000, in particular 6000, on.

With regard to the modes of action or the reasons for the addition of these auxiliaries or processing aids, reference is generally made to the preceding statements.

The formulation may further comprise, in particular for reducing the water content, at least one high-performance plasticizer in a proportion of not more than 1 part by weight, wherein this high-performance plasticizer is preferably a polycarboxylate ether.

Furthermore, the formulation may contain at least one thickener in a proportion by weight of max. 0.5 parts by weight may be added, this thickener is preferably selected from a group comprising hydroxymethylpropylcellulose, methylhydroxyethylcellulose, and mixtures and derivatives thereof.

According to a preferred embodiment, the proportion of the thickener is at most 70% of the proportion of high-performance liquefier.

Furthermore, rheology-improving adjuvants, such as e.g. Means for reducing the viscosity, to be added in order to avoid a decrease in the solid components in the slurry.

It is also possible that the formulation fibers are added in a proportion of at most 3 part by weight, which fibers may have a maximum length of 200 pm in a preferred embodiment, when used to improve the rheological properties, and in particular may be selected from a group comprising cellulose fibers, basalt fibers, glass fibers, in particular alkali-resistant glass fibers, polypropylene fibers, and mixtures thereof. On the other hand, fibers which are added to improve the bending tensile strength have a length of up to 50 mm, in particular between 3 mm and 12 mm.

In order to avoid repetitions, it should be noted at this point that reference is also generally made to the above statements with regard to the individual components of the formulation or of the slurry, of the foam component or of the slurry / foam component mixture.

Further processing aids are alkali carbonates, e.g. U2CO3, alkali sulphates, fruit acids, e.g. Citric acid, or tartaric acid, which may each be contained in a proportion of up to 2 parts by weight.

Preferably, the formulation also has a hydrophobing agent in a proportion of not more than 1 part by weight in order to reduce the water absorption of the finished mineral foam 2, so that thus a smaller reduction of the thermal insulation behavior, ie the thermal conductivity, can be achieved by water absorption.

The foam component may also be admixed with a surfactant to improve the service life of the foam, the proportion of the surfactant in the foam component preferably being at most 10 parts by weight.

Wetting agents known from the prior art, in particular in an amount of up to 0.2 parts by weight, and highly viscous stabilizers, in particular in an amount of up to 0.02 parts by weight, may also be added to the foam component in order to increase the mixing with the slurry improve.

The mineral foam 2 produced by the process according to the invention has pores which have a diameter of not more than 1 mm and may be present in a proportion of mineral foam of 80%.

In the course of tests carried out, the following exemplified compositions of the formulation according to the invention for the slurry according to Table 1 were prepared. In this case, metakaolin was used as the pozzolanically setting binder for Examples 1 to 7 and basalt for Examples 8 to 15. As sulfate, α-hemihydrate of calcium sulfate was used for Examples 1 to 9 and the dihydrate of calcium sulfate for Examples 10 to 15. The foam component was compounded as described in Table 2 using protein hydrolyzed keratin for Examples 1-15. Subsequently, the slurry / foam compositions were prepared according to Table 3, where the number corresponding to the number of Examples in Tables 1 and 2 respectively. All information on the compositions in the tables are to be understood as parts by weight based on the total formulation (Table 1) or based on the slurry / foam mixture (Table 2). It should be noted that in the context of the invention, compositions were also prepared with the other substances mentioned above. The obtained values for the measured properties of the mineral foam 2 are in the range of the indicated values It. Table 3, so that the representation of these examples is omitted, since this would go beyond the scope of this description.

Of these compositions, the thermal conductivity was measured according to EN 1946-2, as well as the compressive strength at a stress of the mineral foam 2 with 0.1 MPa to 0.5 MPa and the corresponding values are given in Table 3.

Table 1: Slurry composition

Nr SAC Puzzolan Sulphate Excipients Water 1 40 40 25 5 35 2 50 40 25 5 35 3 50 30 15 2 25 4 50 30 15 2 35 5 55 20 10 5 35 6 60 20 10 5 30 7 70 20 15 8 30 8 70 20 12 6 30 9 70 15 10 6 25 10 70 15 10 7 25 11 70 10 10 7 20 12 75 10 10 8 20 13 75 10 15 8 20 14 75 5 10 9 20 15 80 5 10 10 18 [00103] Table 2: foam composition

Nr Protein Water Excipients 1 1 60 0 2 1 55 0.2 3 1 50 0.2 4 1 45 0.2 5 1 40 0.2 6 2 60 0.2 7 2 40 0.2 8 2 20 0.5 9 3 60 0.5 10 3 50 0.5 11 3 40 0.5 12 3 30 0.5 13 3 20 1 14 4 60 1 15 5 60 1 11/15 Austrian Patent Office AT 509 011 B1 2011-10-15 Table 3: Slurry / foam composition

No. Slurry Foam Thermal conductivity [W / mK] Compressive strength [MPa] 1 69.40 48.20 0.038 0.10 2 93.60 47.60 0.410 0.2 3 166 47.70 0.052 0.55 4 190 45.00 0.061 0.70 5 250 43.50 0.065 1.0 6 85 40.2 0.078 0.4 7 90 55.5 0.068 0.45 8 100 48.2 0.055 0.67 9 150 47.0 0.060 0.69 10 200 54.0 0.061 0.70 11 70 44.0 0.044 0.9 12 80 48.4 0.042 0.88 13 115 47.5 0.054 0.75 14 100 47.4 0.052 1.2 15 70.0 43.2 0.563 1.5 [00105 ] With regard to the auxiliaries used, reference is made to the above statements.

In addition, it should be noted that the addition of the foam component to the slurry in addition to the described and preferred continuous procedure can also be carried out batchwise.

The embodiment shows a possible embodiment of the device 1, wherein it should be noted at this point that the invention is not limited to the specifically illustrated embodiment of the same.

For the sake of order, it should finally be pointed out that, for a better understanding of the structure of the device 1, these or their components have been shown partially unevenly and / or enlarged and / or reduced in size.

REFERENCE MARKET DESCRIPTION 1 device 2 mineral foam 3 mixing section 4 mixing section 5 storage container 6 conveying device 7 arrow 8 arrow 9 mixing element 10 mixing section shaft 11 foam generator 12 protein 13 storage container 14 arrow 12/15

Claims (27)

Austrian Patent Office AT 509 011 B1 2011-10-15 15 Arrow 16 Reservoir 17 Arrow 18 Arrow 19 Conveying device 20 Conveying device 1. Mineral foam comprising a hydraulically setting component and a foam component, wherein the hydraulically setting component is formed by a formulation for producing a self-hardening mineral foam is comprising a hydraulically setting and a pozzolanic setting binder and a sulfate, wherein the hydraulically setting binder is formed by a sulfate-aluminate cement comprising a sulfate component and an aluminum component, and contained in a proportion of at least 50 parts by weight, characterized in that the sulphate is selected from a group comprising calcium sulphate as anhydrite, dihydrate, α-hemihydrate, β-hemihydrate, magnesium sulphate, sodium sulphate, and mixtures thereof, the proportion of sulphate being between 5 parts by weight and d is 25 parts by weight. 2. mineral foam according to claim 1, characterized in that the sulfate component is selected from a group comprising calcium sulfate, α- or ß-hemihydrate or dihydrate of calcium sulfate, anhydrite, sodium sulfate, iron (II) sulfate, magnesium sulfate and mixtures thereof. 3. mineral foam according to claim 1 or 2, characterized in that the aluminum component is selected from a group comprising alumina, aluminum hydroxides, aluminum silicates, aluminates and mixtures thereof. 4. Mineral foam according to one of claims 1 to 3, characterized in that a ratio of the sulfate component to the aluminum component is selected from a range with a lower limit of 4:10 and an upper limit of 20:30. 5. mineral foam according to one of claims 1 to 4, characterized in that this contains SiO 2 particles in a proportion of not more than 10 parts by weight. 6. mineral foam according to claim 5, characterized in that the SiO 2 is a fumed silica. 7. Mineral foam according to claim 5 or 6, characterized in that the SiO 2 has a BET surface area between 5 m 2 / g and 30 m 2 / g. 8. mineral foam according to one of claims 1 to 7, characterized in that it contains at least one Hochleistungsverflüssiger in a proportion of not more than 3 parts by weight. 9. mineral foam according to claim 8, characterized in that the high-performance liquefier is a polycarboxylate ether. 10. mineral foam according to one of claims 1 to 9, characterized in that it contains at least one thickener in a proportion of not more than 0.5 parts by weight. 11. Mineral foam according to claim 10, characterized in that the thickener is selected from a group comprising hydroxymethylpropylcellulose, methyl-hydroxyethylcellulose, and mixtures thereof. 12. mineral foam according to claim 10 or 11, characterized in that the proportion of the thickener is at most 70% of the proportion of high-performance liquefier. 13. Mineral foam according to one of claims 1 to 12, characterized in that it contains fibers in a proportion of not more than 3 parts by weight. 13/15 Austrian Patent Office AT 509 011 B1 2011-10-15 14. Mineral foam according to claim 13, characterized in that the fibers have a maximum length of 50 mm. 15. Mineral foam according to claim 14, characterized in that the fibers are selected from a group comprising cellulose fibers, basalt fibers, glass fibers, in particular alkali-resistant glass fibers, polypropylene fibers, and mixtures thereof. 16. Mineral foam according to one of claims 1 to 15, characterized in that at least one substance from a group comprising alkali metal carbonates, alkali metal sulfates, fruit acids, is included. 17. Mineral foam according to one of claims 1 to 16, characterized in that at least one hydrophobizing agent is included. 18. Mineral foam according to one of claims 1 to 17, characterized in that it contains no non-reactive constituents. 19. Mineral foam according to one of claims 1 to 18, characterized in that the foam component is formed by a protein foam and / or a surfactant. 20. Mineral foam according to one of claims 1 to 19, characterized in that the proportion of the foam component per m3 slurry between 30 kg / m3 and 70 kg / m3, in particular between 40 kg / m3 and 60 kg / m3, wherein the slurry is formed from the powdered components with the addition of water. 21. Mineral foam according to one of claims 1 to 20, characterized in that the foam component contains a surfactant. 22. Mineral foam according to one of claims 1 to 21, characterized in that a proportion of the pores is at least 70%. 23. Mineral foam according to one of claims 1 to 22, characterized in that the pores have a maximum diameter of 0.5 mm. 24. Component with a component body, characterized in that a mineral foam according to one of claims 1 to 23 is arranged on a surface of the component body and / or within the component body. 25. A process for producing a self-hardening mineral foam according to which powdery constituents for producing a formulation in a first mixing section (3) are mixed together to form a mixture and water is added to this mixture to form a slurry, wherein the slurry is mixed in a second mixing section (4). a foam component is added and mixed into the slurry and then the mineral foam is hardened, characterized in that the formulation as claimed in claims 1 to 18 is composed and the mineral foam is hardened without autoclaving. 26. The method according to claim 25, characterized in that the foam component is added before adding to the slurry in a foam generator with water and optionally processing aids. 27. The method according to claim 25 or 26, characterized in that the proportion of the foam component per m3 of slurry between 30 kg / m3 and 70 kg / m3. For this purpose 1 sheet drawings 14/15