WO2018103794A1

WO2018103794A1 - Method for producing a component from aerated concrete and same

Info

Publication number: WO2018103794A1
Application number: PCT/DE2017/101053
Authority: WO
Inventors: Chris Ralf RÖDER; Rose WEBER; Michael Weber
Original assignee: Roeder Chris Ralf; Weber Rose
Priority date: 2016-12-10
Filing date: 2017-12-08
Publication date: 2018-06-14
Also published as: DE102017129140A1

Abstract

The invention relates to a method for producing a component (10), in particular an insulating panel, made of aerated concrete, comprising the following steps: a) producing a cement paste (20) from water (11), cement, in particular special cement, and at least one additive (13), in particular from the following group of additives i) metakaolin (19) ii) microsilica (15) iii) nanosilica (16) iv) hydroxyapatite (17) v) tricalciumphosphate (18), in a high-speed colloid mixer (19), b) producing a foam (21) from air (22) and foaming agent (23), c) combining the cement glue (20) with the foam (21) in a mixing station (24) and mixing the two components into an aerated concrete.

Description

Process for the manufacture of a structural element of foam concrete and the like

The invention relates according to a first aspect of a method for producing a component, in particular an insulating board.

Such components, in particular said insulation board, for example, consist of polystyrene and can be used in a known manner for use in building insulation, for example, for exterior walls or roof structures. The heat insulation composite systems which are widely used today in building insulation have, as is well known from the media, particular disadvantages in terms of their combustibility and environmental compatibility. They are therefore considered as much in need of improvement.

Other components consist for example of solid concrete, masonry or wood combinations. It is also known to partially mix these materials, for example, by introducing liquid concrete into cavities of masonry or wood containing components or the like.

However, these components usually have the disadvantage that they are relatively heavy, typically need to be stored and appear in need of improvement in various werterer aspects.

Accordingly, the idea underlying the present patent application is to provide a method which makes it possible to produce an improved component, in particular an insulating panel. According to the said first aspect, the invention achieves the stated object with the features of claim 1 and accordingly characterized in particular by the following steps: a) producing a cement paste from water, cement, in particular special cement, and at least one aggregate, in particular from the following group of additives i) Metakaolin

ii) Microsilica

iii) nanosilica

iv) hydroxyapatite

v) trycalcium phosphate, in a high speed colloid mixer,

Producing a foam of air and foaming agent,

Combining the cement paste with the foam in a mixing station and mixing the two components into a foam concrete. In other words, the idea of the invention is a

To produce a component made of a special foam concrete.

Although foam concrete may basically be known from the construction industry, it is typically used merely as filling material. They have not been considered at all due to their special properties for the production of components. Only the production method according to the invention with the addition of the specified additives and the special manufacturing process of the cement paste in a colloid mixer makes it possible to obtain a foam concrete, which is suitable for use in a component.

Foamed concrete is a concrete produced by mixing a cement paste and a foam. Foamed concrete differs in this sense from aerated concrete, which is typically produced by the addition of a blowing agent (for example, aluminum powder) in the cement paste. The propellant leads to foaming of the tough cement paste in aerated concrete. However, there is no mixture of foam and cement paste.

Due to the completely different production methods of foam concrete on the one hand (which is also called pore lightweight concrete or mineral foam) and the aerated concrete on the other hand, arise different structures in the cured concrete. Thus, the pores of aerated concrete components are interconnected by a capillary system. For this reason, aerated concrete components absorb water to a considerable extent. In the case of foam concrete, on the other hand, the individual pores are (at least predominantly) separated from one another and are not connected to one another. Therefore, for example, foam concrete components can absorb no or almost no water.

Another essential difference between foam concrete and aerated concrete lies in the Hersteilungsart: aerated concrete is cured under the influence of heat and pressure. By contrast, the foam concrete according to the invention typically hardens without supply of heat and / or at atmospheric pressure. The foam concrete is produced according to the invention by bringing together or mixing a cement paste with foam. The foam is typically underlaid under the cement paste or vice versa. This is done according to the invention in FIG. 5 of a mixing station, for example a mixing station in the manner of a stirrer. The underlapping or mixing is usually rather low-revving. This allows gentle mixing. The mixing time can be, for example, between a few seconds and a few minutes, for example between 30 seconds and 5 minutes, more preferably between 1 and 2 minutes.

The foam required for this purpose is typically produced in a separate foam unit and then fed to the mixing station. Alternatively, the foam can of course also be produced in the mixing station itself, for example in the manner of a large basin. In both cases, the cement paste can be added to the foam, which is then located in the mixing station, successively or clocked and be undercut or mixed with a stirrer. The cement paste is also referred to as "slurry".

Advantageously, the stirring or leveling done with a certain regularity, with more and more cement paste can be added continuously. This is a known procedure, for example from the Eisschaum or Kaiserschmarrn production area. Preferably, therefore, not all cement paste and all the foam is already in the mixing station at the beginning of the stirring process.

For example, in an exemplary mixing station, one cubic meter of the mixed mass contains 940 liters of foam and 60 liters of cement paste. Of course, this is just an example Value. Of course, said ratio of about 15: 1 may also be between 10: 1 and 20: 1, preferably between 5: 1 and 50: 1.

The mass thus produced, which may also be referred to as (liquid or viscous) 5 foam concrete or foamed concrete raw material, is then typically pumped off and further formed or processed into a structural element

The foam concrete typically has a gross density of between 40 and 400 kg / m ³ , more preferably between 60 and 200 kg / m ³ .

The foam concrete according to the invention is particularly pressure-resistant, for example with a compressive strength of between 0.01 and 0.9 MPa (at a dry density of about 150 kg / m ³ ) or a compressive strength of up to 0.7 MPa at a dry bulk density of 130 kg / m ³ .

The foam which is mixed with the cement paste to produce the foam concrete typically consists of a composition of air and a foaming agent comprising surfactants and / or proteins and / or water. The foaming agent is therefore typically liquid or at least fluid.

The foaming agent is foamed with air to produce the foam, to which preferably the foam former is added to an air space. This can be done using a foam generator, which then directly fills the mixing station with foam or only a separate pool or the like, from which the foam is then fed to the mixing station. Since foaming agent based on proteins is associated with certain disadvantages (such as susceptibility to mold formation or possibly adverse fire protection behavior), proteins may be omitted. Advantageously, the foaming agent and / or the foam and / or the foam concrete lipids, in particular rhamnolipids on.

In other words, rhamnolipids can be used as the foaming agent.

The cement paste is taken according to the invention a colloid mixer, which is also referred to as a colloidal mixer. This colloid mixer is typically very high-speed, which can be achieved, for example, by using a corresponding motor, for example a 50 Hertz motor or a higher or lower rotating motor.

Colloidal or colloidal mixers are used, for example, in the preparation of suspensions with the smallest particles. In addition to the uniform distribution of the solid particles in the fluid phase is the exclusion of the particles, ie the separation of clumps, in focus. One of the goals of particle digestion is to increase the reactive surface area of the material.

Typically, the colloid mixer produces more than 1,000, more preferably more than 2,000, more particularly more than 5,000 revolutions per minute, more advantageously more than 10,000 or even more than 20,000 or more than 50,000 revolutions per minute. The cement paste produced in this way in the colloid mixer consists according to the invention of water, cement and aggregates. The cement may be, for example, special cement, such as Portland limestone cement or Holcim White Portland cement. The grinding fineness can be, for example, between 30 and 60, more advantageously between 32 and 53. Depending on the application, certain additives are used. The aggregates total in the cement paste and / or in the finished foam concrete, a weight fraction of typically between 0.001% and 15% (or even 25% or even 40%), more particularly less than 10%, more particularly between 1% and 7 %, more particularly between 3% to 5%.

Suitable additives are, for example, metakaolin, microsilica, nanosilica, hydroxyapatite, trycalcium phosphate and / or fumed silica. For example, a mixture as a cement, water, metakaolin, fumed silica and hydroxyapatite, more particularly rhamnolipids are used in the further course as a foaming agent. In this way, very stable Schaumbetorrformulierungen can be achieved with pleasingly low thermal conductivities. In this way, thermal conductivities of the components of between 0.02 and 0.06 W / mK can be achieved, more preferably between 0.03 and 0.04 W / mK.

It has been found according to the invention that, in particular, the addition of hydroxyapatite Ca ₅ (.O ₄ ΜΟΗ) 2 to the formulation has an accelerating and stabilizing effect on the foam concrete. This is unusual in that phosphates act rather as setting retarders in concrete curing, but may optionally be explained by the fact that the foam concrete formulation, especially with the addition of metakaolite or metakaolin (this is used interchangeably in the jargon and is in the context of the present application as a synonym understood) forms other calcium silicate phases than in a normal concrete. In addition to or instead of Hydroxyiapatii but also Trycaiciumphosphat can be used, which has similar properties. However, it is crucial that the ingredients water, cement and

In the Koiioidmischer additives are mixed very high speed and then, as already described above, mixed with the foam in a low-speed M / ^' schstation. As a result, a foam concrete or a Schaumbetonrohmasse is generated, which is then issued or can be removed and is a component or can be formed into a component.

This innovative foam concrete, due to its significant advantages over other thermal insulation materials (inexpensive, non-flammable, environmentally friendly, etc.), opens up a large number of new application areas. The obvious development towards the replacement of polystyrene and other known insulating materials requires an adaptation of the foam concrete to the specific requirement profiles of the component structures (eg ETICS or thermal insulation of steep and flat roofs). Extensive application potential for sustainable thermal insulation is formed both in new buildings and in the energetic refurbishment of existing buildings. In addition, future-oriented and completely new constructions are made possible by the advantageous properties and manufacturing methods of the foam concrete, such as a load-bearing composite construction for exterior walls and roofs with concrete, masonry and wood elements,

A typical use is in the outer wall or roof construction. In particular, however, the foam concrete can also be used on the inner wall. Preferably, it is shaped and sawed and / or cut, for example, in the manner of plates or blocks. In this case, it can then be used particularly advantageously as an insulating board, in particular with particularly low thermal conductivity properties.

According to a particularly advantageous embodiment of the invention, the foam concrete, or that of the mixing station withdrawn, further processed into a component. However, if the component does not require any special form, the method can already be considered complete before. The further processing may in particular be a shaping and / or a drying process. For example, in the event that the device is to be formed as an insulating board, should then be optionally still liquid or pulpy or viscous foam concrete in a mold to dry. The shape may be, for example, a formwork.

The finished insulation board can then be formed block or plate-like. In particular, the part taken from the mold can be sawn or cut to size or the like, for example into a plate shape. From a casing, several insulation boards can be worked out in this way. Other forms for other components are of course readily feasible.

However, the foam concrete can also be entered into an existing of another material, such as wood or stone or similar element, which then represents the finished component with the entered, dried foam concrete. The component may in this sense, for example, other materials than foam concrete, in particular wood or stone or another type of concrete or the like. According to a particularly advantageous embodiment of the invention, the foam concrete mixture taken from the mixing station, which in particular may still be liquid or viscous, is further mixed in a colloid mixer.

In other words, the mixture of foam and cement paste is (once again) transferred to a colloid mixer. The colloid mixer may in particular be the colloid mixer in which the cement paste has already been produced or mixed. Of course, the invention also includes that it is another colloid mixer. Advantageously, however, it is the identical colloid mixer and therefore also has all the features described in the application and the like.

Numerous tests have shown that such a process step again defines the final mass particularly with regard to its consistency. In particular, this results in a finer pore pattern and thus in particular a better thermal insulation value of the foam concrete produced.

According to this advantageous embodiment of the method according to the invention, in addition to the advantages mentioned, the foam concrete will in particular have a smaller volume, namely in particular due to a higher (raw) density. Advantageously, such a foam concrete of the same volume becomes more productive in one way (the performance increases). This also allows a more economical use of additives. Of course, however, all the methods of the invention are encompassed in which after removal from the mixing station, the material is not (once again) added to a colloid mixer, but further processed, dried or left. It should be noted at this point that the method according to the invention permits production of the foam concrete, and thus in particular also the production of a corresponding component, "on site", ie, for example, on a construction site or the like At a remote manufacturing site, such as a fabrication shop or the like, and then made to a construction site, the method of the present invention enables a spatial integration of the foam concrete or foam concrete building stage and the construction site, such as the construction site This sense may be unnecessary.

According to a further aspect of the present invention, this relates to a component according to claim 5. This is in particular an insulation board. The device is made of foam concrete and in particular according to one of the described methods hergesteift.

It should be noted at this point that all advantages and embodiments described in connection with the method according to the invention can also be applied to all other independent claims of the present invention. Thus, the component may contain, for example, rhamnolipids, (in particular in the foam), the foam concrete from which the component is made, may have undergone the same process steps in its manufacture, the component may be cut out of a block, etc.

According to a particularly advantageous embodiment of the invention is one or more additives with a weight fraction between 0.001% and 15% contained in the (liquid or viscous) foam concrete mass or the cement paste of the component. Thus, the aggregates do not account for more than 15% by weight of the foam concrete mass or cement paste, preferably not more than 10%.

According to a further aspect of the present invention, the invention relates to a formulation for a cement paste for the production of foam concrete according to claim 6. All the advantages described are of course also applicable to this recipe.

According to a further aspect of the invention, this relates to a foam concrete mass according to claim 8. Here, too, all the advantages and embodiments already mentioned are transferable to the foam concrete mass. This has in particular at least one of the additives mentioned in claim 8. Advantageously, the foaming agent or the foam contains rhamnolipids.

According to a last aspect of the present invention, this also includes a mixing device according to claim 10. The mixing device is designed in particular as a colloid mixer or colloidal mixer. The mixing device according to the invention has a 50 Hertz motor as drive (or a motor with an even higher Hertz number), which in particular allows the high mixing speeds mentioned (more than 5,000 revolutions per minute, in particular more than 10,000 revolutions per minute). The colloid mixer therefore has a different, higher rotating drive than the mixing station. The drives are especially designed separately.

The following should be noted: The invention relates to the production of an insulating panel with a density in particular of 60 to 200 kg / m ³ . The strength of the slab is in a range that allows for transport and processing on construction sites, sufficient load on the facade insulation and provides a thermal conductivity with the following values: λ limit = 0.034 W / (m * K), corresponding values in higher crude density classes to λ limit = 0.0518 W / (m * K).

The invention relates to the technical field of insulation of building exterior sides and / or insides.

The production of the insulation boards is done with a mineral foam, foam concrete, porous lightweight concrete. The insulation boards are poured into molds or blocks (production plant / production line) and switched off after a drying step. Blocks are cut to size in the subsequent operation. An insulation board is created. This eliminates mineral wool insulation or other similar insulation (such as polystyrene). The innovative element of the idea is the building material with its excellent properties in terms of thermal conductivity and strength. Another advantage of this insulating material is its environmental compatibility.

The insulation boards made of mineral foams or foam concretes or porous lightweight concretes can be adjusted individually and in relation to the product in terms of bulk density and thus also with regard to the thermal insulation value.

The selection of the apparent density is preferably between 60 and 200 kg / m ³ .

The heat storage capacity of insulating materials is determined by their bulk density and the specific heat storage capacity. Incidentally, this method has an influence on the building-material-related contribution to the sound insulation of insulating materials, in particular the bulk density, the dynamic stiffness, the degree of sound absorption and the flow resistance. Airborne sound transmission is more influenced by bulk density and sound absorption. The latter is influenced by the construction and use of fiber insulation mainly by their flow resistance.

From an energetic point of view, the highest possible thermal insulation should be sought.

The basis for evaluating the insulating materials is DIN 4108-4, which defines the design values of the so-called thermal conductivity.

With regard to fire behavior, a product advantage is also to be assumed here, since the use of insulating materials provides at least an assignment to the designation "normally flammable".

Fulfillment of higher requirements, for example, "flame retardant" and / or "non-flammable" by a product such as the mineral lightweight concrete according to the invention, in any case also contributes to increased fire protection and is also required by law, depending on the type and building class. Thus, in addition, by the use of the product and method according to the invention an increased fire protection is achieved in comparison to the usual insulation materials.

Incidentally, the long-term behavior as well as the temperature resistance as well as the primary energy consumption are positively influenced compared to other insulating materials. As already indicated, the gross density classes range in particular from 60 kg / m ³ to 200 kg / m ³ and the thermal conductivity is, for example, at the following values: λ limit = 0.034 W / (m * K) and in higher gross density classes corresponding values up to λ limit = 0 , 0518 W / (m * K).

Existing and marketed building products such as insulation boards, Mineraiwolle, etc. are substituted by the inventive method and by the product used or substantially improved in their product properties.

To achieve the erförderlichen product properties of the insulating material of mineral foams and / or foam concrete and / or lightweight concrete pores (such as thermal conductivity and compressive strength) special high-speed mixer are used, which allow a cement paste of water and special cements such

1. Holcim White Poriland Cement CEM I 52.5 N

2. produce Portland limestone cement (CEM ll / A-LL 42.5).

Special additives such as inter alia, metakaolin and / or microsilica and / or nanosilica and / or hydroxyapatite and / or trycalcium phosphate are incorporated into the cement paste to obtain the desired product properties.

In particular, hydroxyapatite, formerly apatite (CaOH), is used for the first time in foam concretes and contributes greatly to improving the compressive strength and the thermal conductivity and processability, in particular in industrial production. Hydroxylapatite crystallizes in the hexagonal crystal system with the chemical formula Ca5 [OH | (P04) 3] and usually develops short to long prismatic crystals of up to 30 cm in length, but also small to massive mineral Agregate, stalactistic forms and crusty coatings. Hydroxylapatite is the basis of the hard substance of bones and teeth of all vertebrates. Hydroxylapatite can also be made in the laboratory to calcium phosphate or tricalcium phosphate.

Test series have shown that the desired results in terms of strength and flexural strength as well as thermal conductivity can be achieved with both substances, the mined apatite, as well as with the industrially produced tricalcium phosphate.

Subsequently, the glue is transferred to a mixer which gently mixes the glue and the foam, which is produced in a separate foam unit, at slow speeds.

The mixing time will be 1 - 2 minutes.

The high-speed colloid mixers with a 50-core drive motor enable new processes and new formulations designed specifically for the new product and application.

Moreover, the invention relates to the following key embodiments:

1. Insulating board made of mineral foams or foam concretes or porous lightweight concretes with a density of 60 to 200 kg / m ³ . The thermal conductivity lies, for example, at the following values: λ limit = 0.034 W / (m * K) and in higher gross density classes corresponding values up to λ limit = 0.0518 W / (m * K). 2. Insulating board made of mineral foams or foam concrete or porous lightweight concrete

- with compressive strength of up to 0.9 MPa at a dry density of 150 kg / m ³ .

- with compressive strengths of up to 0.7 MPa at a dry density of 130 kg / m ³ .

3. Mixing device for the production of cement paste with high mixing speeds by using a 50 Hertz motor as drive.

Formulation consisting of otherwise customary and known compositions using and adding the additives described in the claims.

Further advantages of the present invention will become apparent from optionally not cited subclaims and with reference to the following description of the figures.

Show:

Fig. 1: in the manner of a very schematic diagram, the

Kemablauf a method of the invention, from the individual building materials to the preparation of a foam concrete mixture in a mixing station and

Fig. 2: in a likewise very schematic diagrammatic

View the continuation of a corresponding

Method of a foam concrete mixture to a finished, molded component. The following description of the figures is prefaced that identical or similar parts may be provided with identical reference numerals, partially with the addition of small letters or apostrophes, which are in the description of the claims following the sake of clarity omitted if appropriate.

FIG. 1 initially shows a certain division into two parts. For example, in the left half of FIG. 1, the production of a cement paste 20 is initially shown schematically.

For this purpose, water 11 is mixed with (special) cement 12, in particular with the addition of one or more additives.

These additives may be metakaolin 14 and / or microsilica 15 and / or nanosilica 16 and / or hydroxyapatite 17 and / or trycalcium phosphate 18.

With regard to these substances, it should be noted that the spelling in the figures or in the description of the figures may slightly differ from one another. This may be due to different spellings, as they are in the literature and as they are known in the art.

The mentioned components water 11, (special) cement 12 and in particular one or more aggregates 13, are then mixed in a colloid mixer 19. For this purpose, the components mentioned either individually, for example, one after another, be transferred to the colloid mixer or already previously mixed together and transferred together in the colloid mixer 19. The colloid mixer 19 is a very high-speed colloid mixer which, for example, carries out more than 1000 revolutions, preferably more than 2000 revolutions per minute. Colloid mixers are also known as colloidal mixers

The use of such a colloid mixer in particular means that the corresponding raw materials, minerals, binders, etc. are well digested and mixed. The corresponding reactions can already begin in the colloid mixer.

The additives 13 used for the cement paste can in particular support the crystallization process, which, for example, also decisively supports the stability of the end product. In particular, the aggregates 13 allow a good, namely low, water-to-cement ratio, which is partly responsible for the strength, and in particular also prevents cracking as much as possible.

In the colloid mixer 19, an initially substantially liquid or viscous cement paste 20 is formed in this manner.

So much for producing a cement paste 20 according to the left side of FIG. 1.

The right side of FIG. 1 represents purely schematically the production of a foam 21 to be mixed with the cement paste 20. For this purpose, air 22 is combined with a foaming agent 23 in a separate foam unit, not shown in FIG. 1, and in this way the foam 21 created. In the foam unit, the foaming agent 23 is foamed, for example with the aid of the air 22. The foaming agent 23 is typically present already in liquid form, in particular comprising surfactants and / or proteins and / or water.

Thus, on the one hand the foam 21 is produced and on the other hand the already mentioned cement paste 20, which is also referred to as "slurry".

The foam 21 is now underlined in a next step under the cement paste 20. This is done in a preferably slowly rotating mixing station 24. In the mixing station 24 is in particular a separate from the colloid mixer 19 mixing station. This typically rotates much more slowly than the colloid mixer 19. For example, it may comprise a basin that is initially filled with foam 21. In this foam 21 can then be successively or clocked in a certain amount of cement paste 20 are given. The mixing station 24 may comprise an agitator, which now regularly underlays the foam or the cement paste 20 is undercut in the foam.

The mixing ratio of foam 21 to liquid cement paste 20 or slurry may, for example, be between 5: 1 and 50: 1, preferably between 10: 1 and 20: 1, more preferably about 15: 1. For example, 940 liters of foam 21 and 60 liters of cement paste 20 may be located in one cubic meter of this mass.

The mixing station 24 or said agitator may then mix the foam 21 and the cement paste 20, for example, for less than 5 minutes, for example between half and three minutes mixing time.

FIG. 2 then shows by way of example that the quantity to be taken from the mixing station 24 is either further processed directly at 25 can, or according to a particularly preferred Ausführungsforrn of the inventive method first (once) in a (other or the already known) colloid mixer 19 can be transferred. Test series have shown that remixing in a Koiloidmischer the mass of foam 21 and cement paste 20 for wertere amazing properties of the final product, such as improved stability, a finer pore pattern and / or a better thermal insulation value can provide.

However, the renewed mixing in the colloid mixer 19 'according to an alternative method is not absolutely necessary and it can optionally be done directly further processing at 25, as is illustrated by the arrow in Fig. 2.

It should be noted at this point that the colloid mixer according to FIG. 2 is provided with the reference symbol 19 ^* , since it may be either the colloid mixer 19 already known from FIG. 1 or a separate colloid mixer. However, this too is very high-revving and designed essentially with the same properties, which is why it will typically happen that the colloid mixer 19 according to FIG. 1 and the colloid mixer 19 'according to FIG. 2 are identical.

According to FIG. 2, the subsequent further processing at 25 then takes place towards a finished component 10. This further processing process may consist, in particular, of pouring the mass taken from the mixing station 24 (also called liquid or viscous foam concrete), which may also have been introduced into the colloid mixer 19 ', into molds or blocks. This can then be done in a production plant or production line. After carrying out a drying process, the mold or block can then be switched off and the shaped, dried mass of the desired foam concrete material can be shaped shaping, for example by sawing or cutting or parts or the like. In particular, a corresponding product can be said to measure, according to the shape of a plate, which is then used as an insulating board.

Claims

1. A method for producing a component (10), in particular an insulating board made of foam concrete, comprising the following steps: a) producing a cement paste (20) from water (11), cement, in particular special cement, and at least one aggregate (13), in particular from the following group of aggregates i) Metakaolin (19)

ii) Microsilica (15)

iii) Nanosilica (16)

iv) Hydroxylapatite (17)

v) Trycalcium phosphate (18), in a high speed colloid mixer (19), b) producing a foam (21) from air (22) and foaming agent (23), c) contacting the cement paste (20) with the foam (21) in one Mixing station (24) and mixing the two components to form a foam concrete.

2. The method of claim 1, comprising the following step: d) further mixing of the foam concrete in a colloid mixer (19 ').

3. The method according to claim 1 or 2, comprising the following step:

e) further processing of the foam concrete to a component (10).

4. The method of claim 3, wherein feature e) comprises one or more of the following steps: e1) pouring the, in particular liquid or viscous, foam concrete into a mold or block, e2) stripping the block, e3) sawing the block to size while providing an insulation board.

5. Construction element (10), in particular insulation board, made of foam concrete, in particular produced according to one of the preceding methods, wherein the foam concrete consists of cement paste (20) and foam (21) which are mixed in a mixing station (24), the cement paste ( 20) water (11), cement (12), in particular special cement, and at least one additive (13) from the following group of additives

Metakaolin (19),

Microsilica (15),

Nanosilica (16),

Hydroxyapatite (17),

Trycalciumphosphat (18), which, in particular in a high-rotating colloid mixer (19), are mixed together, and wherein the foam (21) consists of air (22) and foaming agent (23).

6. A formulation for a cement paste (20) for the production of foam concrete, the cement paste (20) comprising the following components: a) water (11) b) cement (12) c) at least one additive from the following group of aggregates (13)

Metakaolin (19)

Microsilica (15)

Nanosilica (16)

Hydroxylapatite (17)

Trycalcium phosphate (18)

7. A formulation according to claim 6, characterized in that the or the aggregates) (13) with a weight proportion of, in particular total, less than 40%, in particular less than 20%, more particularly between 0.001% and 15% (percent by weight) in which cement paste is / are included.

8. foam concrete mass, wherein the foam concrete from cement paste (20) and foam (21), which are mixed in a mixing station (24), wherein the cement paste (20) water (11), cement (12), in particular special cement, and at least an aggregate (13) from the following group of aggregates

·· Metakaolin (19),

ii. Microsilica (15),

iii. Nanosilica (16),

iv. Hydroxyapatite (17),

v. Trycalcium phosphate (18) which are mixed together in a high-speed colloid mixer (19), and wherein the foam (21) consists of air (22) and foaming agent (23).

5

9. foam concrete mass according to claim 8, characterized in that the foaming agent (23) or foam (21) rhamnolipids, in particular no surfactants.

10. mixing device (19, 19 '), in particular colloid mixer, for

Production of cement paste (20) with high mixing speeds, wherein the mixing device has a 50 hertz motor, or a higher-speed motor, as drive or wherein they more than 1,000, in particular more than 5,000, more particularly more than 10,000, more particularly more than 20,000, more particularly more than 50,000 revolutions per minute for mixing the cement paste denies.