Apparatus and method for foaming building material

Abstract

The present invention relates to an apparatus (10) and a method for foaming building materials for producing a structural element and / or building insulation. The apparatus (10) comprises a delivery device (14) in a delivery line (18), in which one or more injection nozzles (28) are provided in order to inject liquid CO 2 into the stream of building material (16). The pressure level in the building-material line (18) is maintained in such a way that the injected CO 2 remains in its liquid aggregate state or transitions into a critical or supercritical state. The building-material / CO2 mixture proceeds downstream into a mixing device (34) and then into at least one or more expansion devices (20), which ensure that a controlled decompression of the building-material / CO2 mixture takes place without it undergoing intense cooling and segregation. Downstream there is a discharge device (66), which is designed to discharge the material for producing a structural element (84) and / or building insulation. Depending on the addition of CO2, the density at the various levels (84, 86, 88) within the structural element (84) can thus be changed ,and with it their properties in the form of load-bearing capacity, heat transfer and mass. If, during the process, CO2 is injected constantly in an amount which can be absorbed by the structural element (16) in the suspension, a building-material foam (68) in the form of, for example, building insulation is produced.

Description

[0001] Applicant: Hubertus Dietrich Winter von Adlersflügel

[0002] Our reference: PT / 22300 / WO

[0003] November 20, 2025

[0004] Device and method for foaming building materials

[0005] The present invention relates to a device for foaming building materials according to the preamble of claim 1, a method for foaming building materials according to the preamble of claim 11 and a foamed building material according to the preamble of claim 22.

[0006] Concrete components made from homogeneous concrete mixtures are used in a variety of ways; in addition, multi-layered systems such as the external thermal insulation composite system or concrete components with core insulation are known.

[0007] In addition to these traditional components, there are new approaches in which either hollow bodies are cast into the components or different concrete mixes with lightweight aggregates are applied one after the other using a spraying process (e.g. EP 4 169 686 Al) in order to save high-density building material in places where few forces are transferred.

[0008] A disadvantage of these known components is that they consist of mixed fractions, which cause major problems during recycling. Furthermore, the latter methods are not economically viable.

[0009] Foam concretes, in which cement is mixed into a foam, are also well-known. After the cement hardens, components with a low specific weight are produced. However, due to an unfavorable water-cement ratio and the foaming agent used, which usually consists of surfactants or proteins, the strength of the components is reduced so drastically that they can no longer bear loads. Components foamed with air-entraining agents exhibit similar properties. Furthermore, foam concretes have no early strength and can therefore only be processed horizontally.

[0010] Based on this prior art, the object of the present invention is to provide foamed building materials with which one or more of the aforementioned disadvantages are overcome. Preferably, components manufactured with these building materials should exhibit high load-bearing capacity and / or excellent insulating properties. In particular, the components should be economical to manufacture and their properties should be easily adaptable depending on the desired application. Preferably, the components should also be producible vertically.

[0011] This problem is solved by the inventive device for foaming building materials according to claim 1, the inventive method for foaming building materials according to claim 11 and the inventive foamed building material according to claim 22. Advantageous embodiments are specified in the dependent claims and in the following description together with the figures.

[0012] The inventors recognized that this problem could be solved surprisingly easily by introducing a gas in a liquid state into the building material and then depressurizing the resulting building material-gas suspension. This causes the gas to transition into a gaseous state, resulting in the building material foaming. Depending on the concentration of the introduced gas in the building material, building material foams with varying degrees of foaming, and thus with different load-bearing capacities and insulating properties, can be produced. Preferably, the gas is injected into the building material.To prevent the gas from immediately transitioning into the gaseous state, thus making a homogeneous mixture of the aerosol impossible due to the difference in the specific gravity of the components, the building material is compressed so that the gas in the building material-gas suspension remains in the liquid state or at most transitions into a critical or supercritical state.

[0013] The device according to the invention for foaming a building material, comprising a feed device for supplying the building material and a discharge device for dispensing the foamed building material, which are connected via a conveying line, is characterized in that it includes a compression device for compacting the building material, an injection device for introducing a liquid gas into the compacted building material to form a building material-gas mixture comprising the building material and the gas, and an expansion device for expanding the building material-gas mixture, wherein the compression device is adapted to compact the building material in such a way that, after the introduction of the liquid gas, the gas in the building material-gas mixture remains in the liquid state or transitions into a critical or supercritical state.

[0014] The injection nozzles allow the liquid gas to be introduced into the compacted building material as a very fine spray. After the expansion of the building material-gas mixture, and the associated change of state of the gas from liquid, critical, or supercritical to gaseous, small bubbles are formed, creating the building material foam.

[0015] Furthermore, by selecting the control of a desired number of injection nozzles and changing the injection duration, the dosage of the gas in the building material can be specifically adjusted.

[0016] Such gases could be, for example, gases with a high melting point that pose no health hazard and are highly available, such as CO2 and CO2 mixtures.

[0017] Such building materials can be mineral-bound, organic, inorganic building materials or building materials held together by a binder and may preferably be selected from the group of cementitious, geopolymeric and clay-like building materials, in particular from the group comprising: mortar, clay and alkali-activated geopolymers.

[0018] In a further advantageous embodiment, the expansion device comprises a volume-changing element, preferably a movable wall, particularly in the form of a movable piston or a hose located between two compression bodies, with which the volume of an expansion chamber can be changed. The expansion chamber preferably has an inlet valve in conductive contact with the supply device and an outlet valve in conductive contact with the dispensing device. Most preferably, a pressure sensor is included for measuring the pressure in the expansion chamber. This results in a particularly simple and efficient design. The volume-changing element is preferably actuated by an electric linear motor, because this allows the stroke length and stroke speed to be freely selected, thus optimizing the decompression of the building material with regard to foam quality.When the building material is ejected from the expansion chamber, the conveying pressure can be selected by controlling the stroke speed so that the generated foamed building material can be dispensed from the dispensing device with optimized pressure with regard to rebound and compaction.

[0019] In a further advantageous embodiment, the injection device is designed as an injection device and preferably comprises at least one electronically controlled injection nozzle and a high-pressure delivery device, and in particular at least one pressure equalization tank. The gas can be added very precisely by controlling the number and duration of the injection nozzle's opening pulses. The injection nozzle allows the gas to be introduced into the building material under high pressure and as a very fine spray.

[0020] In a further advantageous embodiment, the material supply device includes a quantity measuring device. By measuring the quantity of material, the required amount of CO2 can be injected according to the desired porosity of the component being manufactured.

[0021] In a further advantageous embodiment, an additive dispensing device is arranged between the depressurization device and the dispensing device. This dispensing device preferably comprises at least one electronically controlled injection nozzle and a pressure adjustment device, and in particular at least one pressure equalization tank. This allows the properties of the foamed building material to be precisely adjusted. Such additives can be selected, for example, from the group consisting of: setting retarders, setting accelerators, water repellents, and viscosity modifiers.

[0022] Construction foams, especially those with an optimized water-cement ratio, are generally very unstable and prone to coalescence. To counteract this, the time until the suspension sets is minimized by adding accelerators. For this reason, an advantageous embodiment of the invention has at least one or more injection nozzles downstream that inject setting accelerators and / or curing accelerators and / or other additives as a fine spray into the construction foam. In a further advantageous embodiment, a first homogenization device for homogenizing the construction foam-gas mixture is provided between the injection device and the expansion device. This first homogenization device is preferably designed as a dynamic mixing device, in particular as a continuous mixing device comprising agitators. This results in particularly uniform foaming.

[0023] In a particularly advantageous embodiment, a second homogenization device is provided between the depressurization device and the dispensing device for homogenizing the foamed building material-additive mixture. This second homogenization device is preferably designed as a dynamic mixing device, in particular as a continuous mixing device comprising agitators. This ensures particularly uniform mixing with the additive. Alternatively, the addition of additives without mixing is also possible.

[0024] In an advantageous embodiment, a density sensor is provided between the expansion device and the dispensing device for determining the density of the foamed building material or the foamed building material-additive mixture, wherein the density sensor is preferably designed as a Coriolis mass flow meter. This allows the generated density and thus the porosity to be easily checked.

[0025] In a further advantageous embodiment, a flow meter is arranged between the inlet device and the pressure relief device and / or between the pressure relief device and the outlet device. This allows the mass flow to be precisely controlled.

[0026] In a further advantageous embodiment, a pressure sensor is arranged between the pressure release device and the output device. This allows the output pressure to be precisely controlled.

[0027] Advantageously, the density sensor can also determine the mass flow rate of the foamed building material or the foamed building material-additive mixture. This is preferably designed as a Coriolis mass flow meter. In a further advantageous embodiment, a monitoring device is provided for monitoring the flow behavior and / or coalescence of the dispensed foamed building material or the dispensed foamed building material-additive mixture, wherein the monitoring device is preferably designed as an image acquisition device, laser scanner, or ultrasonic scanner. The image acquisition device can capture still images or a continuous video stream. For example, it can be checked whether the dispensed building material retains a rigid shape or whether this shape deforms. If the shape deforms, more setting accelerator could be added and / or the foaming could be reduced.

[0028] In an advantageous further development, a conveying device, preferably a pump, is provided in the conveying line. This allows the foamed building material to be easily transported within the system and / or dispensed very easily. The conveying device is specifically designed to maintain the building material at a pressure level such that the added gas remains in its liquid state or transitions into a critical or supercritical state.

[0029] In a further advantageous embodiment, the delivery device includes a conveying device for the gas, preferably designed as a pump. This allows the gas to be supplied to the building material very easily.

[0030] In a further advantageous embodiment, the adding device includes a conveying device for the additive, preferably designed as a pump. This allows the additive to be added to the building material very easily.

[0031] In an advantageous further development, it is provided that a control device exists which controls at least one actuator of the device, wherein the control device is preferably adapted to perform the control based on measured values ​​of at least one sensor of the device, wherein in particular at least one actuator of the device is from the group comprising:

[0032] - the feed device for supplying the building material, - the compaction device for compacting the building material,

[0033] - the dispensing device for the dispensing of the foamed building material,

[0034] - the injection device for introducing the liquid gas into the building material,

[0035] - the pressure relief device for the pressure relief of the building material-gas mixture,

[0036] - the inlet valve,

[0037] - the exhaust valve,

[0038] - the first homogenization device for homogenizing the building material-gas mixture, - the addition device for additives,

[0039] - the second homogenization device for homogenizing the foamed building material additive mixture and

[0040] - the high-pressure gas delivery device

[0041] - the conveying device for the additive

[0042] and / or at least one sensor of the facility from the group encompassing:

[0043] - the quantity measuring device for measuring the quantity of building material supplied,

[0044] - the pressure sensor for measuring the pressure in the pressure release device,

[0045] - the pressure sensor for measuring the output pressure of the building material gas mixture,

[0046] - the flow meter for measuring the flow rate of building material

[0047] - the flow meter for measuring the flow rate of foamed building material or foamed building material additive mixture,

[0048] - the density sensor for determining the density of the foamed building material or the foamed building material additive mixture and

[0049] - the monitoring device

[0050] have been chosen.

[0051] This makes it very easy and structurally simple to carry out numerous control and regulation processes of the device, especially with regard to those described within the framework of the method according to the invention.

[0052] A first preferred control process involves using the density of the generated building material foam, determined by the density sensor, as the control variable for the corresponding setpoint-actual control system, which in turn controls the injection device for introducing the liquid gas into the building material. This allows for targeted adjustment of the porosity. A second preferred control process involves using parameters from the monitoring device as the control variable for the corresponding setpoint-actual control system, which in turn controls the additive injection device. This allows for targeted adjustment of the properties of the foamed building material, particularly its flow behavior and coalescence.

[0053] A third preferred control method involves using the pressure in the pressure relief device as the control variable for the corresponding setpoint / actual value control system for the control of the pressure relief device and / or the outlet valve. This ensures controlled pressure relief.

[0054] A fourth preferred control method involves using the output pressure as the control variable for the corresponding setpoint / actual value control system for the pressure relief device. This allows the output pressure to be precisely adjusted.

[0055] A fifth preferred control process involves using the mass flow rate of the building material as the control variable for the corresponding setpoint / actual value control system for the inlet valve of the pressure relief device. This allows the fill quantity into the pressure relief device to be precisely adjusted.

[0056] Independent protection is claimed for the inventive method for foaming a building material, wherein the foamed building material is dispensed, characterized in that the building material is compacted, a liquid gas is introduced into the compacted building material, and the resulting building material-gas mixture, which has the building material and the gas in a liquid, critical, or supercritical state, is expanded in a decompression chamber.

[0057] In a further advantageous embodiment, the device according to the invention is used. This allows the method to be implemented particularly simply and cost-effectively.

[0058] In a further advantageous development, the pressure in the conveying line is adjusted so that the gas in the building material-gas mixture is in a liquid, critical, or supercritical state. This enables a continuous flow of building material from the feed device to the pressure relief device.

[0059] In a particularly advantageous embodiment, the construction material-gas mixture is subjected to controlled expansion, preferably to ambient pressure. This results in a particularly homogeneous construction material foam. When using an expansion chamber, the volume of the expansion chamber is preferably enlarged, depending on the amount of gas added to the construction material, until the gas is subsequently at ambient pressure.

[0060] Controlled decompression prevents the generated construction foam from separating and / or from undergoing intensive cooling, which could lead to the construction foam freezing and thus blocking the system.

[0061] In a further advantageous development, it is provided that a first additive, preferably a setting retarder, is mixed into the building material. This enables continuous transport of the building material within the facility.

[0062] In a further advantageous embodiment, a second additive, preferably a setting accelerator, is mixed into the foamed building material. This enables the rapid setting of the building material foam after dispensing.

[0063] In a particularly advantageous advanced training program, CO2 is used as the gas. This makes the foamed building material especially cost-effective to produce.

[0064] Another advantage is that the thermal transmittance of CO₂ is much lower than that of air. Foams whose pores are filled with CO₂ thus exhibit significantly higher insulation values ​​for the same component thickness. Furthermore, the building material reacts with the CO₂, leading to positive effects regarding the amount of CSH phases and consequently to higher strength.

[0065] In a further advantageous embodiment, the building material comprises at least one inorganic component, preferably a binder, and mortar is used as the building material. Such building materials exhibit particularly advantageous properties with regard to load-bearing capacity and insulation.

[0066] In a further advantageous development, it is provided that the porosity of the foamed building material (or the foamed building material-additive mixture) is determined and the introduction of the gas into the building material is controlled in such a way that a desired porosity of the foamed building material (or the foamed building material-additive mixture) is achieved. This enables corresponding target-actual control, whereby a desired porosity of the building material foam can be specifically adjusted.

[0067] In a further advantageous development, the discharge of the foamed building material from a pressure relief chamber is controlled in such a way that a desired flow rate of the foamed building material is established in the conveying line. This allows the building material foam to be dispensed from the dispensing device at a desired pressure.

[0068] In an advantageous further development, it is provided that at least one parameter, preferably one from the group comprising: flow behavior and coalescence of the dispensed foamed building material, is monitored, and the addition of the second additive is controlled in such a way that a specific parameter is achieved. This allows for easy target-actual control of certain properties of the building material foam.

[0069] In a further development, it is provided that the building material-gas mixture is homogenized. This results in the produced building material foam having particularly uniform properties.

[0070] In a further advantageous development process, the foamed mixture of building material and additives is homogenized. This also results in the produced building material foam exhibiting particularly uniform properties.

[0071] In a further advantageous embodiment, the foamed building material is used to produce a component, preferably a load-bearing component or an insulating component, whereby the component is produced in particular by wet spraying, 3D printing, or the classic method for manufacturing aerated concrete blocks. The load-bearing component can be prefabricated or manufactured on-site. These components exhibit particularly advantageous properties with regard to load absorption and / or insulation performance.

[0072] In a further advantageous embodiment, the component is manufactured in layers, with the density of the foamed building material preferably being adjusted differently over at least two layers. This allows for the particularly simple production of complex components. Preferably, the component can thus achieve high load-bearing capacity on its outer walls and high insulation performance in its interior.

[0073] In a further advantageous embodiment, it is provided that a continuous or discrete change in the properties of the building material foam in the component is generated by layer-by-layer monotonous foaming in at least one spatial direction. This also allows complex components to be manufactured particularly easily. Preferably, the component can thus also achieve high load-bearing capacity on its outer walls and high insulation performance in its interior.

[0074] Furthermore, independent protection is claimed for the foamed building material according to the invention, which is characterized in that it is produced using the inventive method and / or the inventive device.

[0075] The claims submitted now, as well as those submitted later, do not prejudice the obtaining of further protection.

[0076] Should closer examination, particularly of the relevant prior art, reveal that one or more features are advantageous but not essential for the objective of the invention, a formulation is naturally being sought that no longer includes such a feature, especially in the main claim. Such a sub-combination is therefore also covered by the disclosure of this application.

[0077] The cross-references cited in the dependent claims indicate the further development of the subject matter of the main claim by the features of the respective dependent claim. However, these are not to be understood as a waiver of the right to obtain independent, substantive protection for the features of the cross-referenced dependent claims.

[0078] It should also be noted that the embodiments and variants of the invention described in the various embodiments and shown in the figures can be combined with one another in any way. Individual or multiple features are interchangeable. These combinations of features are also disclosed.

[0079] Features disclosed only in the description, or individual features from claims comprising multiple features, may at any time be incorporated into the independent claim(s) as being essential to the invention for the purpose of distinguishing it from the prior art, even if such features were mentioned in connection with other features or achieve particularly favorable results in connection with other features.

[0080] Thus, all features described in the general description of the invention, the description of the exemplary embodiments, the subsequent claims, and the figures can be essential to the invention, both individually and in any combination. These features or combinations of features can each constitute an independent invention, the right to claim which is expressly reserved. Individual features from the description of an exemplary embodiment need not necessarily be combined with one, several, or all other features specified in the description of that exemplary embodiment; any sub-combination is expressly disclosed. Furthermore, material features of a device or apparatus can be reformulated and used as process features, and vice versa.Such a reformulation is therefore automatically disclosed.

[0081] The features and further advantages of the present invention will become clear below with reference to the description of a preferred embodiment in conjunction with the figure. Figure 1 shows, purely schematically, the apparatus according to the invention for producing the building material foam according to the invention.

[0082] The device 10 according to the invention has a storage container 12 as a supply device, from which a conveying device 14 (pump) transports the building material 16 (for example mortar) located in the storage container 10 via a conveying line 18 to a pressure relief device 20.

[0083] An injection device 22 is arranged between the supply device 12 and the expansion device 20, by which gas (for example, CO₂) is supplied from a pressure reservoir 24 via a gas line 26 to three injection nozzles 28. A pressure boosting system 30 in the form of a pump and a pressure equalization tank 32 are interposed.

[0084] Downstream of the injection nozzles 28 is a first mixing device (homogenizing device) 34, which is designed as a dynamic mixing device with a whisk.

[0085] The first section 36 of the conveying line 18 leads via an inlet valve 38 into the pressure relief device 20.

[0086] The expansion device 20 has an expansion chamber 40, the volume of which is adjustable via the movable wall 42 between the minimum volume shown in Fig. 1 and a maximum volume (not shown). The wall 42 is designed as a movable piston, which is driven, for example, by an electric linear motor 44.

[0087] Furthermore, there is an outlet valve 46 which is connected to a second section 48 of the delivery line 18 (output line).

[0088] Downstream of the expansion device 20, an injection device 50 is arranged, which has a storage container 52 for additives 54. Furthermore, the injection device 50 has one or more pressure boosting units 56 (pumps) and one or more pressure equalization tanks 58. A density sensor 62 is arranged between the expansion device 20 and the injection nozzle 60 for the additive 54, and downstream of the injection nozzle 60, in the second section 48 of the delivery line 18, is a second mixing device (homogenizing device) 64, which is again designed as a dynamic mixing device with a whisk. The density sensor 62 is designed as a Coriolis mass flow meter, so that it can measure not only the density but also the mass flow of the construction foam.

[0089] Downstream of the second mixing device 64 is a dispensing device 66, with the help of which a spray jet of the building material foam 68 is generated.

[0090] Furthermore, the device 10 has a first flow meter 70 in the first section 36 of the delivery line 18, a pressure sensor 72 in the second section 48 of the delivery line 18 for determining the pressure in the output line 48, a pressure sensor 74 for determining the pressure in the expansion chamber 40 and a monitoring device 76 in the form of a video camera.

[0091] Furthermore, a control and regulating device 78 is provided, which is connected via numerous communication lines 80a, 80b, 80c, 80d to the injectors 28 of the injection device 22, the flow meter 70 and the pressure sensors 72, 74, the inlet valve 38, the outlet valve 46, the density sensor 62 and the linear motor 44, as well as to the injector 60 and the monitoring device 76. Additional communication lines, for example to the conveying device 14, to the pressure boosting systems 30, 56 and to the mixing devices 34, 64, may exist, but are not shown. The communication lines 80a, 80b, 80c, 80d can be wired or wireless.

[0092] The device 10 also has a production level 82, which can be arranged vertically or horizontally, but also inclined, on which components 84 can be produced from the building material foam 68 produced with the device.

[0093] The apparatus for producing the foamed building material 68 according to the invention is operated as follows: The building material 16 is forced into the conveying line 18 by means of the conveying device 14. Liquid CO₂ is injected into the flow of the building material 16 via the injection nozzles 28. The opening of the injection nozzles 28 is electronically controlled by the central control device 78. The amount of injected CO₂ can be continuously varied and metered in real time by the length of the opening pulses of the injection nozzles 28 within a time interval and by the number of injection nozzles 28 controlled simultaneously.

[0094] The building material-CO₂ mixture forms a suspension and flows downstream into the mixing device 34, which homogenizes this suspension.

[0095] The conveying device 14 is controlled by the control device 78 such that the pressure level in the conveying line 18 and 36 is maintained so that the CO₂ dispersed in the construction material suspension remains in a liquid state or, at most, transitions into a critical or supercritical state. The suspension of construction material and CO₂ is homogenized in the mixing device 34. In other words, the conveying device 14 acts as a compression device; it simultaneously seals the conveying line 18 against pressure in the direction of the feed device 12, so that the construction material 16 can be compressed in the direction of the expansion device 20.

[0096] The suspension then flows into the expansion chamber 40 of the expansion device 20 through the opening of the inlet valve 38, while the outlet valve 46 is closed, controlled by the central control unit 78. At this point, the position of the piston 42 is at the upper end point of its stroke, resulting in the minimum volume of the expansion chamber 40 shown in Fig. 1.

[0097] Once the expansion chamber 40 is completely filled with the suspension, the inlet valve 38 is closed. The closing time of the inlet valve 38 can be determined by the control device 78 based on the readings of the flow meter 70 or based on a specific pressure in the expansion chamber 40, which is determined by the pressure sensor 74.

[0098] By a slow stroke movement of the piston 42 towards the lower endpoint, which increases the volume of the expansion chamber 40, the suspension is decompressed, whereby the CO₂ evaporates in a controlled manner and the suspension thus becomes a foam, the building material foam.

[0099] Controlled decompression prevents the building material foam from separating and from undergoing intensive cooling, which could lead to the building material freezing.

[0100] The maximum piston stroke is set by the control and regulating device 78 so that, depending on the injected gas quantity, the foamed building material forming in the expansion chamber 40 is present at normal pressure, i.e., ambient pressure with respect to the device 10. The piston speed is controlled in such a way that the boiling of the liquid gas is controlled.

[0101] When normal pressure is reached, which is confirmed by the pressure sensor 74, the outlet valve 46 opens while the inlet valve 38 remains closed. The piston 42 is then moved by the linear motor 44 towards its upper endpoint, thereby conveying the construction foam downstream into the second section 48 of the delivery line 18 at the appropriate pressure. The delivery pressure can be continuously and in real time adjusted by the control device 78 by controlling the piston speed. The signal from the pressure sensor 72 is used as the control pulse.

[0102] The density of the produced building material foam, determined via the density sensor 62, serves as a control variable for the corresponding setpoint-actual control for the control of the injection device 22.

[0103] Through one or more injection nozzles 60, setting accelerators and / or other additives 54 are added to the foamed building material. This is also useful because setting retarders have been added to the building material 16 in the storage container 12 to prevent clogging of the device 10 due to premature setting.

[0104] The quantity of injected additives 54 is continuously variable and metered in real time via opening pulses from the central control unit 78 to the injection nozzles 60. The control variable of the corresponding setpoint / actual control for the metering of additives 54 is provided by the monitoring device 76, which is designed as a camera, but can alternatively also be designed as a 3D laser scanner, ultrasonic scanner, or the like.

[0105] This monitoring device 76 monitors the flow behavior and coalescence of the foamed building material 68 during the production of the component 84. If the building material foam 68 flows too freely or is too coalescent, the addition of setting accelerators 54 is increased. Conversely, if the building material foam 68 flows too little or is not coalescent enough, the addition of setting accelerators 54 is decreased.

[0106] The second mixing device 64 homogenizes the foamed mixture of building material and additives.

[0107] With this advantageous design, building material foams 68 can be produced which have a high early strength and can therefore also be processed horizontally on the construction site as wall elements 84 and / or wall insulation.

[0108] To ensure a continuous output of construction foam 68, at least two expansion devices 20 can be connected in parallel with respect to the delivery line 18, so that when the construction material gas mixture is expanded in one expansion device, construction foam generated in the other expansion device 20 is simultaneously output.

[0109] The building material foam 68, dispensed by wet spraying, is now used to produce the components 84 according to the invention on the production level 82. In the illustrated example, a layer 86 is first produced from a less densely foamed building material 68, in which the density of the building material foam 68 is relatively high.

[0110] Subsequently, a thicker layer 88 is produced from a maximally foamed building material 68, in which the density of the building material foam 68 is relatively low.

[0111] Finally, a layer 90 is produced from the less densely foamed building material 68, in which the density of the building material foam 68 is again relatively high. The component 84 produced in this way thus has walls 86, 90 that serve to absorb forces, and a core 88 that has excellent insulating properties.

[0112] By controlling the CO₂ dosage, a change in the properties of the applied building material foam 68 can be achieved in at least one spatial direction, preferably two or three. Depending on how continuously or discretely the CO₂ dosage is increased, the structure of the building material foam 68 changes from a solid structure to a foam matrix of very low density. This makes it possible to adapt the component structures as desired according to the requirements of structural design and simultaneously for sound and / or thermal insulation, while significantly saving building material and thus CO₂.

[0113] Alternatively or additionally, pure building insulation can be produced by maximum foaming with CO₂.

[0114] A further advantage of the invention lies in the long-term storage of CO₂ in component 84. This long-term storage has a further positive effect, namely that the thermal transmittance of CO₂ is much more favorable than that of air. Building material foams 68, whose pores are filled with CO₂, thus exhibit much higher insulation values ​​for the same component thickness. In addition, the building material 16 reacts with the CO₂, which leads to positive effects regarding the quantity of CSH phases and thus to higher strength.

[0115] Although the advantages of the present invention have been described using cementitious building materials foamed with CO₂, it is clear that the invention can in principle be used for any building materials and foaming gases.

[0116] Alternatively, 3D printing or the classic production of aerated concrete blocks can be used instead of the wet spraying process.

[0117] In this case, the pressure relief device 20 is designed as a piston decompression pump. However, other configurations are also possible. One alternative embodiment consists, for example, of a hose arranged between two cuboid pressure bodies, at least one of which is movably mounted. Clamping the hose between the pressure bodies causes a change in cross-section, thus providing a pressure relief chamber of variable volume.

[0118] After opening an inlet valve, the suspension flows into the clamped hose. When the two pressure chambers are closed, the cross-section of the hose increases as the pressure on them expands, causing the material to foam up, similar to the previously described piston decompression pump. The construction foam can then be dispensed by opening a previously closed outlet valve and clamping the hose again.

[0119] It has become clear from the foregoing description that the present invention makes it possible to produce a building material foam 68 which no longer exhibits the disadvantages of known building material foams. Components 84 manufactured with this building material foam 68 exhibit high load-bearing capacity and / or excellent insulating properties.

[0120] Depending on the amount of gas added, the levels 84, 86, and 88 within component 84 can be modified with respect to their density and thus their properties in terms of load-bearing capacity, thermal conductivity, and mass. If the amount of CO₂ injected during the process is constant and corresponds to the amount that the building material 16 can absorb in the suspension, a building material foam 68 is created, for example, in the form of building insulation, i.e., with maximum foam formation.

[0121] These components 84 can be manufactured economically, and their properties can be easily adapted depending on the desired use. The economic efficiency is primarily due to the fact that the building material foam 68 according to the invention can be produced and dispensed continuously. Reference numeral list

[0122] 10 Device according to the invention used in the process according to the invention The device according to the invention 12 Storage container, feed device

[0123] 14 Conveying device, compaction device, high-pressure pump 16 Building material, mortar

[0124] 18 Conveyor line

[0125] 20 Relaxation device, piston decompression pump 22 Injection device, insertion device

[0126] 24 pressure reservoirs

[0127] 26 Gas pipeline

[0128] 28 injectors

[0129] 30 High-pressure conveying device, pump

[0130] 32 pressure equalization tanks

[0131] 34 first mixing device

[0132] 36 first section of the pipeline 18

[0133] 38 Inlet valve

[0134] 40 relaxation room

[0135] 42 movable wall, piston, volume change element

[0136] 44 electric linear motor

[0137] 46 Exhaust valve

[0138] 48 second section of the supply line 18, output line

[0139] 50 Addition device

[0140] 52 storage containers

[0141] 54 additives

[0142] 56 Pressure boosting system, pump

[0143] 58 pressure equalization tanks

[0144] 60 Injector nozzle

[0145] 62 Density sensor

[0146] 64 second mixing device

[0147] 66 Output device

[0148] 68 Building material foam

[0149] 70 Flow meter 72 Pressure sensor Output line 48

[0150] 74 Pressure sensor, relaxation device 20 76 Monitoring device, video camera 78 Control and regulating device

[0151] 80a, 80b, 80c, 80d communication lines

[0152] 82 Production level

[0153] 84 Component according to the invention

[0154] 86 first layer

[0155] 88 core

[0156] 90 second layer

Claims

Patent claims 1. Device (10) for foaming a building material (16) comprising a feed device (12) for feeding the building material (16) and a discharge device (66) for discharging the foamed building material (68), which are connected via a conveying line (18), characterized in that it comprises a compression device (14) for compacting the building material (16), an injection device (22) for introducing a liquid gas into the compacted building material (16) to form a building material-gas mixture comprising the building material (16) and the gas, and an expansion device (20) for expanding the building material-gas mixture, wherein the compression device (14) is adapted to compact the building material (16) in such a way that, after the introduction of the liquid gas, the gas in the building material-gas mixture remains in the liquid state or transitions into a critical or supercritical state.

2. Device (10) according to claim, characterized in that the expansion device (20) comprises a volume change element (42), preferably a movable wall, in particular in the form of a movable piston (42) or a hose located between two press bodies, with which the volume of an expansion chamber (40) can be changed, wherein the expansion chamber (40) preferably has an inlet valve (38) which is in conductive contact with the supply device (12), and an outlet valve (46) which is in conductive contact with the dispensing device (66), wherein most preferably a pressure sensor (74) is provided for measuring the pressure in the expansion chamber (40).

3. Device (10) according to claim 1 or 2, characterized in that the insertion device is designed as an injection device (22) and preferably has at least one electronically controllable injection nozzle (28) and a high-pressure conveying device (30) and in particular at least one pressure equalization reservoir (32).

4. Device (10) according to one of the preceding claims, characterized in that the feed device (12) comprises a quantity measuring device (70).

5. Device (10) according to one of the preceding claims, characterized in that a [missing text] is connected between the release device (20) and the dispensing device (66). Addition device (50) for additives (54) is arranged, wherein the addition device (50) preferably has at least one electronically controlled injection nozzle (60) and a pressure adjustment device (56) and in particular at least one pressure equalization tank (58).

6. Device (10) according to one of the preceding claims, characterized in that a first homogenization device (34) for homogenizing the building material-gas mixture is provided between the injection device (22) and the expansion device (20), wherein the first homogenization device (34) is preferably designed as a dynamic mixing device, in particular as a continuous mixing device comprising stirring means, and / or that a second homogenization device (64) for homogenizing the foamed building material additive mixture (68) exists between the relaxation device (20) and the dispensing device (66), wherein the second homogenization device (64) is preferably designed as a dynamic mixing device, in particular as a continuous mixing device comprising stirring means.

7. Device (10) according to one of the preceding claims, characterized in that a density sensor (62) for determining the density of the foamed building material (68) or the foamed building material-additive mixture is provided between the expansion device (20) and the dispensing device (66), wherein the density sensor (62) is preferably designed as a Coriolis mass flow meter, and / or that a pressure sensor (72) for measuring the pressure in the output line (48) exists between the relaxation device (20) and the output device (66).

8. Device (10) according to one of the preceding claims, characterized in that a flow meter (62) is arranged between the insertion device (22) and the pressure relief device (20) and / or between the pressure relief device (20) and the dispensing device (66) and / or that a monitoring device (76) is provided for monitoring the flow behavior and / or coalescence of the dispensed foamed building material (68) or the dispensed foamed building material additive mixture, wherein the monitoring device (76) is preferably designed as an image acquisition device, laser scanner or ultrasonic scanner.

9. Device (10) according to one of the preceding claims, characterized in that a conveying device (14) is provided in the conveying line (18), which is preferably designed as a pump, and / or that the injection device (22) has a conveying device (30) for conveying the gas, which is preferably designed as a pump, and / or that the addition device (50) according to claim 5 comprises a conveying device (56) for conveying the additive (54), which is preferably designed as a pump.

10. Device (10) according to one of the preceding claims, characterized in that a control device (78) is comprised which controls at least one actuator of the device (10), wherein the control device (78) is preferably adapted to perform the control based on measured values ​​of at least one sensor of the device (10), wherein in particular at least one actuator of the device (10) is selected from the group comprising: - the feed device (12) for the supply of the building material (16), - the compaction device (13) for compacting the building material (16), - the dispensing device (66) for dispensing the foamed building material (68), - the injection device (22) for introducing the liquid gas into the building material (16), - the expansion device (20) for expanding the building material-gas mixture, - the inlet valve (38), - the exhaust valve (46), - the first homogenization device (34) for homogenizing the building material-gas mixture, - the addition device (50) for additives, - the second homogenization device (64) for homogenizing the foamed building material additive mixture (68) and - the high-pressure conveying device (30) of the gas - the conveying device (56) of the additive and / or at least one sensor of the facility (10) comprising group: - the quantity measuring device for measuring the quantity of building material supplied (16), - the pressure sensor (74) for measuring the pressure in the expansion device (20), - the pressure sensor (72) for measuring the output pressure at the building material gas mixture (68), - the flow meter (62) for measuring the flow rate at foamed building material (68) or at foamed building material additive mixture, - the flow meter (70) for measuring the flow rate of building material. - the density sensor (62) for determining the density of the foamed building material or the foamed building material additive mixture and - the monitoring device (76) have been chosen.

11. Method for foaming a building material (16), wherein the foamed building material (68) is dispensed, characterized in that the building material (16) is compressed, a liquid gas is introduced into the compressed building material (16) and the resulting building material-gas mixture, which has the building material (16) and the gas in a liquid, critical or supercritical state, is expanded in a relaxation space (20).

12. Method according to claim 11, characterized in that the device (10) according to one of claims 1 to 10 is used.

13. Method according to one of claims 11 or 12, characterized in that the pressure in the conveying line (18) is adjusted so that the gas in the building material-gas mixture is in a liquid, critical or supercritical state.

14. Method according to one of claims 11 to 13, characterized in that the building material-gas mixture is depressurized in a controlled manner, wherein the depressurization preferably takes place to ambient pressure.

15. Method according to one of claims 11 to 14, characterized in that a first additive, preferably a setting retarder, is added to the building material (16) and / or that a second additive, preferably selected from the group comprising: setting accelerators, water-repellent agents and viscosity modifiers, is added to the foamed building material (68) and / or that CO₂ or a CO₂ gas mixture is used as the gas and / or that the building material (16) is a mineral-bound, organic, inorganic building material or building materials held together by means of a binder and is preferably selected from the group of cementitious, geopolymeric and clay-like building materials, in particular from the group comprising: mortar, clay and alkaline-activated geopolymers.

16. Method according to one of claims 11 to 15, characterized in that the porosity of the foamed building material (68) is determined and the introduction of the gas into the building material (16) is controlled in such a way that a desired porosity of the foamed building material (68) is achieved.

17. Method according to one of claims 11 to 16, characterized in that the discharge of the foamed building material (68) from a relaxation chamber (40) is controlled in such a way that a desired flow rate and / or pressure for the foamed building material (68) is established in the conveying line (18).

18. Method according to one of claims 11 to 17, characterized in that at least one parameter, preferably a parameter from the group comprising: flow behavior and coalescence of the dispensed foamed building material (68) is monitored and the addition of the second additive (54) according to claim 15 is controlled such that a certain parameter is established.

19. Method according to one of claims 11 to 18, characterized in that the building material-gas mixture is homogenized and / or that the foamed building material additive mixture (68) is homogenized.

20. Method according to one of claims 11 to 19, characterized in that a component (84), preferably a load-bearing component or an insulating component, is produced with the foamed building material (68), wherein the component is produced in particular by wet spraying, by 3D printing or by the classic method for producing aerated concrete blocks.

21. Method according to claim 20, characterized in that that the component (84) is manufactured layer by layer, wherein the density of the foamed building material (68) is preferably adjusted differently over at least two layers (86, 88, 90), and / or that by layer-by-layer monotonous foaming a continuous or discrete change in the properties of the building material foam (68) in the component (84) is produced in at least one spatial direction.

22. Foamed building material (68), characterized in that it is produced using the method according to one of claims 11 to 21 and / or the apparatus (10) according to one of claims 1 to 10. - 11 -

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