WO2016156971A1

WO2016156971A1 - System for injecting a low-density aqueous mineral foam into a construction element

Info

Publication number: WO2016156971A1
Application number: PCT/IB2016/000422
Authority: WO
Inventors: Christian Blachier; Olivier Refouvelet; Cédric ROY; Sébastien COLOMER; Cédric JAILLET
Original assignee: Lafarge
Priority date: 2015-04-02
Filing date: 2016-04-04
Publication date: 2016-10-06
Also published as: FR3034442A1; FR3034442B1

Abstract

The present invention relates to a system (1) for injecting a low-density aqueous mineral foam (M), in particular a cement foam, into a cell (101) of a construction element (100), in particular into a cell of a construction block, comprising: a means (2) for storing the aqueous mineral foam (M); a means (3) for adjusting the flow of the aqueous mineral foam (M) from the storage means (2) towards the outside of the storage means (2), said adjustment means (3) being movable between a first position (P1) or a first operating state in which the flow of the aqueous mineral foam (M) is allowed and a second position (P2) or a second operating state in which the flow of the aqueous mineral foam (M) is interrupted; a control means (4) arranged to control the movement of the adjustment means (3) so as to collect a volume of aqueous mineral foam (M) from the storage means (2); and a means (5) for conveying the aqueous mineral foam (M), arranged between the storage means (2) and the cell (101) of the construction element (100), the conveying means (5) being sized so as to grant the aqueous mineral foam (M) an estimated maximum shear velocity of 55 s^-1, preferably 30 s^-1, and more preferably 5 s^-1.

Description

System for introducing a low density aqueous mineral foam into a building element

The present invention relates to the technical field of construction.

More specifically, the present invention relates to a system for introducing a low density aqueous mineral foam into a cell of a building element, as well as a semi-continuous process for introducing a low density aqueous mineral foam. in a cell of a building element.

In the field of building construction, the criterion of thermal performance is relatively important and is directly related on the one hand to the thermal conductivity of the building elements used to build a building and on the other hand to the assembly of these elements. which can favor the appearance of thermal bridges at their junction.

It is therefore necessary to minimize the thermal conductivity of the building elements while preserving the structural function of these building elements.

There are many types of materials to form building elements for large works. It is possible to mention among others terracotta (for example hollow or cellular brick of the Monomur ™ type), cementitious materials (for example concrete blocks or blocks, cellular concretes or autoclaved) or vegetable matter (for example the hemp like Chanvribloc ™).

These building elements are generally in the form of masonry blocks.

The thermal performance of a masonry block depends directly on the material in question but also on the ability of the block to keep still air inside the block.

Thus, the higher the immobile air volume contained in a building element, the better the thermal performance of the building element.

In order to introduce air into a building element it generally comprises a plurality of cells or cavities.

However, these cells do not limit the movement of air inside the cell, including convection movements and even after masonry block.

To limit the movement of air inside the cells, it is known to insert into the cells of so-called thermally insulating materials.

These thermally insulating materials may be of organic origin or of mineral origin. Thermally insulating materials of organic origin generally comprise materials derived from carbon chemistry and its compounds, natural or synthetic, for example polystyrene or polyurethane.

Thermally insulating materials of mineral origin can be derived from the transformation of minerals into fibrous materials, for example glass wool or rockwool.

Materials of mineral origin also include mineral foams, for example cement foam otherwise known as concrete foam.

Unlike some materials of organic origin, materials of mineral origin have the advantages of not being inflammable, of being inert, of being rot-proof and of having a limited rate of water absorption allowing them to preserve their thermal performance, including maintaining their original density.

In addition, the materials of mineral origin are recyclable and may be of the same nature as the building element that contains them when it is made from cementitious materials.

The mineral foam has the additional advantage of being able to adapt to a given shape and to be able to adhere to a wall.

In general, mineral foam refers to a material in the form of a foam. This material is lighter than traditional concrete because of the pores or voids it includes. ^*

These pores or voids are due to the presence of a gas, usually air, in the mineral foam forming a network of bubbles more or less distant from each other and stably maintained in a solid envelope of mineral binder .

The manufacture of a mineral foam is delicate because it results from the solidification of a liquid foam into a solid foam. Thus, the network of air bubbles or gas surrounded by a slurry of hydraulic binder present in a liquid mineral foam evolves over time into a solid mineral foam.

Also the manufacture of mineral foams involves the passage through a manufacturing step of a liquid foam. The stability of the liquid foam is important, and the manufacturing process should be able to control the phenomena of destabilization of the foams during setting, such as coalescence, Ostwald ripening or drainage.

These destabilization phenomena are all the more important that the density of the foam is low because of the increase in the volume fraction of air. There is a wide variety of mineral foams mainly characterized by their density after drying. This density directly affects their thermal performance.

Thus, the lower the density of the mineral foam, the better the thermal performance.

Therefore, it appears interesting to introduce a low density mineral foam in the cells of a masonry block.

The expression "low density mineral foam" is used to mean a mineral foam having, after drying, a density of less than 300 kg / m ³ , preferably less than 200 kg / m ³ , even more preferably less than 150 kg / m ³ even less than 100 kg / m ³ , which represents respectively an air percentage of at least 83%, 88%, 91% and 94% in the mineral foam.

FR 14/63226 in the name of the applicant describes a continuous manufacturing process of a sufficiently stable low density aqueous mineral foam.

The term "stable" used to qualify the aqueous mineral foam should be interpreted as the ability of the mineral foam to maintain a number, size and distribution of bubbles over time.

This aqueous mineral foam uses a range of protein-based foaming agents.

Aqueous mineral foams using other ranges of foaming agents generally have a density greater than or equal to 300 kg / m ³ .

Mineral foams with densities below 300 kg / m ³ generally require the addition of a specific stabilizing agent.

Mineral foams with a density greater than or equal to 300 kg / m ³ are, for example, applications for the patching of screeds or for the insulation of roof terraces.

These mineral foams are less sensitive to shear stresses and can therefore be pumped during their implementation on site, which is not the case for low density mineral foams.

Indeed, mineral foams made with protein-type foaming agents are disposed to promote the coalescence of their gas or air bubbles when subjected to shear stresses, which has the consequence of increasing the density foam or, in the most extreme cases, to destabilize the foam. Therefore, a low density aqueous mineral foam can not be pumped by conventional pumps, which are used for pumping relatively higher density mineral foams.

Thus, one of the objectives of the present invention is to limit the shear stresses during the use of the mineral foam.

These difficulties are exacerbated when the manufacturing process is a continuous process, that is to say that the finished product is developed in an uninterrupted manner. Continuous manufacturing processes are well suited to an industrial environment and are recommended in the factory or on a construction site.

However, the building elements are generally manufactured in a semi-continuous process using industrial machines, for example a vibrating press.

Thus, a vibrating press sequentially produces several series of construction elements.

Therefore, to introduce low density aqueous mineral foam into the cells of a construction element manufactured by a semi-continuous process, it is necessary that the system for introducing the aqueous mineral foam into a cell of an element. The construction company can adjust its pace on the production rate of the construction elements.

The introduction system of the aqueous mineral foam must therefore allow the implementation of a semi-continuous process.

Thus, another object of the present invention is to control the flow of the aqueous mineral foam so as to alternate interrupt and continuous flow sequences.

In addition, the semi-continuous process must be able to be implemented during the manufacture of an entire series of building elements.

The present invention aims to achieve all or part of the objectives mentioned above.

Thus, the present invention relates to a system for introducing a low density aqueous mineral foam, in particular a cement foam, into a cell of a building element, in particular in a cell of a masonry block, comprising :

a means for storing the aqueous mineral foam,

a means for regulating the flow of the mineral foam from the storage means to the outside of the storage means, said regulating means being movable between a first position or a first operating state in which the flow of the mineral foam is allowed and a second position or a second operating state in which the flow of the mineral foam is interrupted,

a control means arranged to control the movement of the regulating means so as to take a volume of mineral foam from the storage means,

- routing means of the inorganic foam disposed between the storage means and the cavity of the building element, the routing means being sized to impart to the inorganic foam maximum estimated shear rate of 55 s ^{" 1} , preferably 30 s ^-1 , and even more preferably 5 s ^-1 .

Of course, the construction element may comprise a plurality of cells.

The regulating means may then comprise a plurality of control sub-devices controlled independently by the control means.

Similarly, the routing means may also include a plurality of routing sub-devices.

The storage means makes it possible to collect a large quantity of aqueous mineral foam manufactured according to a continuous manufacturing process.

The control means makes it possible to allow and interrupt the flow of the aqueous mineral foam and thus makes the system compatible with a semi-continuous method of introducing aqueous mineral foam into a cell of a building element.

The estimated shear rate is deduced from the calculation of the ratio of the average flow rate of the aqueous mineral foam through the conveying means to the wet perimeter of this means of the section of said conveying means.

A low estimated shear rate in the conveying means makes it possible to limit the shear stresses that can be applied to the aqueous mineral foam during its displacement from the storage means to the cell of the construction element.

Thus, this system makes it possible to implement a semi-continuous process for introducing an aqueous mineral foam, in particular a cement foam, into a cell of a building element while limiting the shear stresses on the foam. mineral.

Moreover, such a system can easily be integrated on an existing production line because all the equipment that composes it can be disposed above said existing production line.

According to one aspect of the invention, the control means is arranged to control the movement of the regulating means so that the determined volume of mineral foam taken is greater than or equal to the volume necessary to fill the cell of the building element.

This arrangement makes it possible to compensate for the withdrawal of the mineral foam observed after the mineral foam has dried.

Such a control means can also be connected to a control means, for example to a rangefinder of the optical detector type, which would determine in real time the filling level of the cell.

According to one aspect of the invention, the control means is connected to a means for controlling the filling level of the cell.

This arrangement makes it possible to ensure the correct mineral foam filling of a cell.

In addition, when the construction element comprises several cells to be filled simultaneously, this arrangement makes it possible to homogenize the filling of all the cells of the building element.

Thus, the level control means may indicate to the control means that one cell fills more quickly than another and adjust the flow rates of mineral foam flowing through the control means for each cell.

According to one aspect of the invention, the system comprises relative displacement means between the construction element and the conveying means.

This arrangement makes it possible to vertically align an outlet of the conveying means and a cell of the construction element so that the aqueous mineral foam flows naturally into the cell under the simple effect of the hydrostatic pressure.

According to a first embodiment of the invention, the routing means comprises:

an intermediate chamber disposed downstream of the regulating means and arranged to receive the extracted volume of aqueous mineral foam,

an injector intended to be arranged opposite the cell,

a piston movable in the intermediate chamber between a first position in which the volume of the intermediate chamber is maximum and a second position in which the volume of the intermediate chamber is minimal, the passage from the first position to the second position being intended for push the collected volume of aqueous mineral foam present in the intermediate chamber to the injector.

Such a system makes it possible, on the one hand, to dose a predefined and adjustable volume of foam without additional control, for example using a telemeter of the optical detector type, of the filling rate of the cell and, on the other hand, of adjust the injection rate at the rate of production of the building elements. According to one aspect of the invention, the injector comprises a valve movable between a first position in which the flow of the aqueous mineral foam is allowed and a second position in which the flow of the aqueous mineral foam is interrupted.

This arrangement makes it possible to create a so-called dropper device preventing any residues of mineral foam from flowing out of the conveying means after the evacuation of the construction element.

According to one aspect of the invention, the injector comprises an inverted valve having a base wider than its top.

This arrangement makes it possible to project the aqueous mineral foam towards the edges of the cell so as to obtain a better distribution of aqueous mineral foam inside the cell.

According to one aspect of the invention, the control means is further arranged to control the movement of the piston and, if appropriate, the valve of the injector.

This arrangement makes it easier to parameterize the movements of the regulating means, the piston and, if appropriate, the movements of the valve of the injector.

According to one aspect of the invention, the movements of the regulating means, the piston and, if appropriate, the valve of the injector are defined according to several predefined operating phases in which these movements are made sequentially and cyclically.

This arrangement makes it possible to define an industrial cycle for manufacturing building elements comprising a low density mineral foam.

According to one aspect of the invention, the regulating means comprises a valve, preferably a butterfly valve or a sleeve valve.

This arrangement ensures the regulating function while limiting the shear stresses on the mineral foam.

According to a second embodiment, the conveying means comprises a pipe connected to the storage means and the regulating means comprises a slide valve contiguous to the outlet of the pipe, the pipe being intended to open out facing the cell. of the building element.

This embodiment also makes it possible to simplify the implementation of the semi-continuous introduction process for introducing an aqueous mineral foam, in particular a cement foam, into a cell of a building element.

Moreover, the pipe described in this embodiment allows higher flow rates of the aqueous mineral foam and therefore better productivity. According to a third embodiment, the conveying means comprises a pipe connected to the storage means, said pipe being intended to open facing the cell of the construction element and said pipe being sufficiently flexible to be able to interrupt the flow of the aqueous mineral foam when the section of the pipe is narrowed.

This embodiment makes it possible to simplify the implementation of the semi-continuous introduction process for introducing an aqueous mineral foam, in particular a cement foam, into a cell of a building element.

In addition, the conveying means does not include moving parts in contact with the mineral foam, which avoids a potential fouling of moving parts.

According to one aspect of the invention, the regulating means comprises a device for narrowing the section of the flexible pipe.

According to a fourth embodiment, the storage means comprises a closed buffer tank and the control means further comprises a pressure regulating means disposed on the buffer tank.

This embodiment makes it possible to adapt the flow rate of mineral foam at the outlet of the storage means as a function of the rate of movement of the construction elements.

According to one aspect of the invention:

a single pipe or, where appropriate, a single injector is arranged for the introduction of the aqueous mineral foam into a cell, in this case the pipe or, if appropriate, the injector is arranged to be centered on and positioned vertically from the center of the cell bottom of the building element, or

several pipes or, where appropriate, several injectors are arranged for the introduction of the aqueous mineral foam into a cell, in this case the plurality of pipes or, if appropriate, the plurality of injectors are arranged to be centered on and arranged at aplomb:

- the center of a portion of the bottom of the cell of the building element whose length results from a division in equal parts of the length of the bottom of the cell of the building element in a number of times equal to the number of pipes of the plurality of pipes or, if appropriate, to the number of injectors of the plurality of injectors or else

- points of intersection between a first line crossing the bottom of the cell along its length and positioned at half its width and second straight lines transverse to this first line crossing the bottom of the cell over its width and positioned at a distance from an edge equal to an integer multiple of the ratio between the length of the bottom of the cell and secondly the number of pipes plus one.

This arrangement makes it possible to adapt to the size and therefore to the volume of the cell in the presence so as to homogenize the distribution of the mineral foam inside the cell.

In addition, this arrangement allows filling from the bottom of the cell to its opening by limiting the pressure exerted on the walls during the flow of the mineral foam.

According to one aspect of the invention, the system comprises a rinsing device of the conveying means arranged for cleaning the mineral foam residues possibly present in the dispensing means.

This provision makes it possible to carry out preventive maintenance on the conveyance means of the mineral foam.

The present invention also relates to a semi-continuous process for introducing a low density aqueous mineral foam, in particular a cement foam, into a cell of a building element comprising the following steps:

- have a construction element comprising a cell,

- Take a volume of mineral foam from a storage means of the aqueous mineral foam,

conveying the sampled volume of mineral foam to the cell at a maximum estimated shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 ,

- introduce the collected volume of mineral foam into the cell of the building element.

This method allows the use of a continuous process of manufacturing low density aqueous mineral foam to achieve a semi-continuous process of introducing a low density aqueous mineral foam, in particular a cement foam, into a cell of a building element.

In addition, such a semi-continuous process makes it possible to limit any losses due to the continuous manufacturing process, while limiting the shear stresses that can be applied to the mineral foam during the implementation of the process.

According to one implementation of the method, the steps are performed from a system for introducing an aqueous mineral foam into a cell of a building element as described above. According to one implementation of the method, the method comprises a preliminary step in which the aqueous mineral foam is heated before being introduced into the cell of the construction element, the heating temperature being close to the temperature of a hardening chamber in which is intended to dry the building element.

This step aims to prevent a deformation of the construction element after passing through the hardening chamber.

According to one implementation of the method, the heating of the mineral foam is carried out by heating the water used for the production of the aqueous mineral foam.

The water has a thermal inertia which allows the mineral foam to remain relatively warmer throughout the semi-continuous process of introduction and until the steaming of the building element.

According to one implementation of the method, the construction element is in the fresh state. The definition of the fresh state for a concrete is provided in the standard NF EN 206-1 dating from October 2005 concerning the specification, performance, production and conformity of concrete.

According to this standard a fresh concrete is a fully mixed concrete and still in a state to compact with the chosen method.

This same standard also provides a definition of a hardened concrete as a solid-state concrete having acquired significant strength.

Similar definitions can be extrapolated for building elements made from other materials than cement, such as earth or plant material.

The use of a construction element in the fresh state allows for the semi-continuous process of introduction of an aqueous mineral foam during the manufacturing process of a building element.

According to one implementation of the method, the construction element is in the cured state, the method then has a preliminary step of wetting the construction element until the water absorption coefficient of the 10-minute building element is less than 5 g / (m ² · s), preferably less than 4 g / (m ² · s), still more preferably less than 3 g / (m ² · s).

The wetting of the construction element makes it possible to limit the absorption of the mineral foam by the construction element and thus to limit the destabilization of the mineral foam.

The procedure for determining the capillary water absorption coefficient of a building element is detailed in the NF EN 772-11 standard dating from August 2011 on the determination of the capillary water absorption of aggregate concrete, autoclaved aerated concrete, natural stone and natural stone masonry elements and the initial water absorption rate of masonry elements. terracotta.

According to one implementation of the method, the volume of mineral foam removed is greater than the volume of the cell to be filled with the construction element or the volume of mineral foam taken is greater than the sum of the volumes of the cells to be filled with the building element.

This arrangement makes it possible to compensate for the phenomenon of removal of a mineral foam observed after drying.

According to one implementation of the method, the method comprises a subsequent step of grinding a face of the construction element by which the mineral foam has been introduced into the cell of the building element, this step being carried out after the drying of the mineral foam and the construction element in the fresh state in which the mineral foam has been introduced, or after drying of the mineral foam of the building element in the cured state in which the foam mineral was introduced.

This step eliminates the excess mineral foam used to fill the cell.

In addition, this step can be carried out simultaneously with the rectification of the construction element.

The present invention also relates to a building element comprising one or more cells, wherein the cell or cells comprise low density mineral foam introduced following the implementation of the method of introduction as described above.

This arrangement provides a construction element having a relatively high thermal performance.

According to one aspect of the invention, the construction element is a masonry block, in particular a concrete block or a brick.

This arrangement makes it possible to decline the solution to different types of construction elements.

In any case, the invention will be better understood with the aid of the description which follows, with reference to the appended schematic drawing showing, by way of nonlimiting example, an example of a system, method and element of construction according to the invention.

Figure 1 is a block diagram illustrating the operating principle of a system according to the invention.

Figure 2 illustrates a system according to a first embodiment. FIG. 3 illustrates an initial phase of operation of the system of FIG. 2. FIG. 4 illustrates a metering phase of the system of FIG. 2.

FIG. 5 illustrates an injection phase of the system of FIG. 2.

Figure 6 illustrates a first position of a regulating means of a system according to a second embodiment.

FIG. 7 illustrates a second position of the regulation means of the system of FIG. 6.

Figure 8 illustrates a first position of a regulating means of a system according to a third embodiment.

FIG. 9 illustrates a second position of the regulation means of the system of FIG. 8.

FIG. 10 illustrates the operating principle of a system according to a fourth embodiment

Figure 11 illustrates a first variant of the aforementioned embodiments. Figure 12 illustrates a second variant of the aforementioned embodiments.

Figure 13 illustrates a third variant of the aforementioned embodiments.

Figure 14 illustrates the steps of a method according to the invention.

Figure 15 illustrates a construction element according to the invention.

As illustrated in FIG. 1, a system 1 for introducing a low-density aqueous mineral foam M into a cavity 101 of a construction element 100 comprises a storage means 2 for the aqueous mineral foam M, a regulating means 3 the flow of the mineral foam M from the storage means 2 to the outside of the storage means 2, a control means 4 of the control means 3 and a means 5 for conveying the mineral foam M disposed between the storage medium 2 and the cell of the construction element 100.

Such a system is particularly suitable for the introduction of cement foam into a cavity 101 of a masonry block 100.

The storage means 2 is for example a hopper or a tank large enough to receive a quantity of aqueous mineral foam M manufactured according to a continuous manufacturing process.

The regulating means 3 is arranged wholly or partly at the outlet of the storage means 2.

This regulating means 3 is movable between a first position P1, or a first operating state, for example a running state in the case of a worm, in which the flow of the aqueous mineral foam M is authorized and a second position P2, or a second operating state, for example a state in the case of a worm, in which the flow of the aqueous mineral foam M is interrupted.

Such a regulating means 3 comprises for example a butterfly valve 3a disposed inside a pipe at the outlet of the storage means 2.

Such a regulating means 3 may also comprise a worm passing through the storage means 2.

These two types of control means limit the formation of shear stresses in the mineral foam M.

The control means 4 is arranged to control the movement of the regulating means 3 so as to take a volume of aqueous mineral foam M from the storage means 2.

In the case of a control means 3 comprising a butterfly valve 3a, the control means 4 is arranged to bring the butterfly valve 3a into its first open position P1 or to bring the butterfly valve 3a into its second position P2 of closing.

Furthermore, in addition to the transitions between the two positions P1, P2 of the regulating means, the control means 4 also manages the duration during which the butterfly valve 3a is in its first position P1 and the duration during which the butterfly valve 3a is in its second position 2.

The dimensions of the outlet pipe as well as the gate valve 3a can be adjusted to take up more or less aqueous mineral foam M in the storage means 2.

In the case of a regulating means 3 comprising a worm, the control means 4 is arranged to drive the worm between the first operating state in which the worm is rotating and the second operating state. wherein the worm is stationary.

Furthermore, in addition to the transitions between the two operating states of the regulating means 3, the control means 4 also manages the duration during which the worm is in its first operating state and the duration during which the worm is in second operating state.

The pitch of the worm and the speed of rotation can be adjusted to take more or less aqueous mineral foam M in the storage means 2.

Thus, the control means 4, as a function of the control means 3 in question, makes it possible to control the volume of mineral foam M taken from the storage means 2.

This volume of aqueous mineral foam M taken is greater than or equal to the volume necessary to fill the cell 101 of the construction element 100 of in order to compensate for the withdrawal of the mineral foam M during its drying and to keep a construction element 100 having the same thermal performance over its entire height.

Of course, the present invention is not limited to a particular type of regulating means 3 and control means 4 and on the contrary covers all the equivalent technical means for taking a volume of aqueous mineral foam M from a storage means 2 by limiting the shear stresses on the aqueous mineral foam M.

The routing means 5 is arranged to guide the volume of mineral foam M taken from the storage means 2 to the inside of the cell 101 of the construction element 100.

In addition, the conveying means 5 is sized to give the aqueous mineral foam M an estimated maximum shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 .

As can be seen in Table 4 below, these speeds limit the shear stresses on the aqueous mineral foam M and thus preserve its stability.

Several embodiments depending on the positioning of the regulating means 3 with respect to the conveying means 5 in the system 1 are conceivable.

Thus, the regulating means 3 may be arranged downstream of the conveying means 5, upstream of the conveying means 5 or even at the level of the conveying means 5.

The system 1 also comprises relative displacement means between the construction element 100 and the conveying means 5 so as to replace a building element 100 filled with mineral foam M with a new building element 100 to be filled.

These displacement means comprise for example the displacement means used in the vibrating presses for moving a wooden board 6 on which is molded a series 7 of construction elements.

These displacement means are arranged to evacuate the wooden board 6 on which is disposed a series 7 of building elements 100 molded and filled with mineral foam M by another wooden board 6 intended for molding another series 7 d building elements 100.

The displacement means may also allow relative movement between the conveying means 5 and the construction elements 100 of the same series 7 of construction element 100 arranged on the same wooden board 6. In a first embodiment illustrated in FIG. 2, the regulation means 3 is arranged upstream of the conveying means 5.

In this first embodiment, the conveying means 5 mainly comprises an intermediate chamber 10, an injector 1 intended to be arranged facing the cell 101 of the construction element 100, and a piston 12 movable in the chamber intermediate 10.

The intermediate chamber 10 is disposed downstream of the regulating means 3 and connected thereto by a T-flange connection 15.

In addition, the intermediate chamber 10 is connected to the injector 11 by the T-flange connection 15 and by a pipe 16 connecting the injector 11 and the T-flange connection 15.

As illustrated in Figures 3 to 5, the piston 12 is movable between a first position P1 'in which the volume of the intermediate chamber 10 is maximum and a second position P2' in which the volume of the intermediate chamber 10 is minimal.

The piston 12 and / or the valve of the injector 13 can be actuated pneumatically, hydraulically or electrically.

The stroke of the piston 12 can be adjusted by an adjusting device 7.

The passage from the second position P2 'to the first position Ρ is intended to suck up the extracted volume of mineral foam M from the storage means 2 in the intermediate chamber 10.

The passage from the first position P1 'to the second position P2' is intended to push the collected volume of mineral foam M present in the intermediate chamber 10 to the injector 11.

As illustrated in FIGS. 3 to 5, the injector 11 comprises a valve 13 movable between a first position P1 "in which the flow of the aqueous mineral foam M is authorized and a second position P2" in which the flow of the foam M aqueous mineral is interrupted.

The present valve 13 is of the inverted valve type having a base wider than the top.

In the example shown, the valve 13 has a conical shape and bears on a seat 14 of conical complementary shape when the valve 13 is in its second position P2 ".

Thus, the valve 13 ensures a diffuse distribution in the cell 101 of the construction element 100.

However, the inverted valve 3 could have any other shape whose base is wider than the top, in particular volumes whose base can be ovoid or polygonal. The movements of the regulation means 3, the piston 12 and the valve 13 of the injector 11 are controlled by the control means 4.

Thus, the control means 4 makes it possible to define an operating cycle of the system 1 comprising a plurality of sequential phases.

In the operating phases of the system 1 according to the first embodiment illustrated in FIGS. 3 to 5, the movements of the piston 12 are represented by a solid arrow and the displacement of the aqueous mineral foam M in the conveying means 5 and if necessary through the injector 11 are represented by dashed arrows.

As illustrated in FIG. 3, the cycle starts with an initial phase in which the regulation means 3 is in its second position P2, the piston 12 is in its second position P2 'and the valve 13 of the injector 11 is in its second position. second position P2 ".

Then, as illustrated in FIG. 4, the system 1 starts a metering phase of the mineral foam M in which the regulation means 3 switches from its second position P2 to its first position P1 for a predetermined duration so as to take a volume mineral foam M from the storage means 2.

During this metering phase of the mineral foam M, the piston 12 also switches from its second position P2 'to its first position P1' so as to create a depression inside the intermediate chamber 10 which sucks the mineral foam M from the storage means 2.

During this same metering phase, the valve 13 of the injector retains meanwhile its second position P2 ".

The volume taken is greater than or equal to the volume necessary to fill the cell 101 of the building element 100 with aqueous mineral foam M.

Finally, as illustrated in FIG. 5, during an injection phase carried out immediately after the metering phase, the regulation means 3 switches from its first position P1 to its second position P2, the piston 12 switches from its first position. position P1 'to its second position P2' and simultaneously the valve 13 of the injector 11 switches from its second position P2 "to its first position P1".

Thus, the aqueous mineral foam M is evacuated from the intermediate chamber 10 by the piston 12 to the injector 11 via the T-flange connection 15 and via the pipe 16.

The estimated shear rate of the aqueous mineral foam M between the intermediate chamber 10 and the injector 11 is at most 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 , so as to limit the shearing of the aqueous mineral foam M. The mineral foam M is then introduced into the cell 101 of the construction element 100.

Finally, the system 1 returns to its initial rest phase, the valve 13 of the injector 11 then switches from its first position P1 "to its second position P2".

A new operating cycle is then initiated.

It should be noted that several operating cycles may be necessary to boot the system 1.

Indeed, the volume of aqueous mineral foam M must first fill the volume of the T-flange connection 15, the pipe 16 and the injector 11 so that the mineral foam M can be evacuated by the valve 13 of the injector 11.

Of course, the mineral foam M taken is not the same as the mineral foam M flowing out of the injector 11, however the volume of mineral foam M taken is substantially identical to the volume of mineral foam M at the outlet of the injector 1.

Of course, the system 1 may comprise several ducts 16 each connecting the T-flange connection 15 and the intermediate chamber 10 to a plurality of injectors 11 each disposed facing a cell 101 of the building element 100.

In this case, the volume taken from mineral foam M is substantially identical to the sum of the volumes of mineral foam M at the outlet of each of the injectors 11.

In addition, the system 1 may comprise a rinsing device (not shown) comprising a storage means for a rinsing liquid, for example water, and a regulating means.

This rinsing device replaces the storage means 2 and the control means 3 of the system 1 during a rinsing cycle.

Thus, a rinsing cycle can be performed between two operating cycles of the system 1.

However, the period of this rinse cycle is greater than the period of one operating cycle.

It is also possible to rinse the system by replacing the aqueous mineral foam M contained in the storage means 2 with a rinsing liquid when the continuous process for manufacturing the mineral foam M is interrupted.

In a second embodiment illustrated in FIGS. 6 and 7, the regulating means 3 is disposed downstream of the conveying means 5.

In this second embodiment, the conveying means 5 comprises a pipe 20 connected to the storage means 2. As shown in Table 3, this pipe 20 is sized to give the mineral foam M a maximum estimated shear rate of 55 s ^" preferably 30 s ^{" 1} , and even more preferably 5 s ^"1 so as to limit the shear aqueous mineral foam M.

The pipe 20 is intended to open facing the cell 101 of a construction element 100.

The section of the pipe 20 is therefore less than or equal to the section of the cell 101 so that the mineral foam M is introduced entirely into the cell 101.

In this second embodiment, the regulating means 3 comprises a slide valve 3b.

The slide valve 3b is disposed adjacent to the outlet of the pipe 20. In addition, the slide valve 3b comprises an opening 21 of section greater than or equal to the section of the pipe 20 and a solid portion 22 of upper section. or equal to the section of the pipe 20.

The slide valve 3b is movable in translation between its first position P1 illustrated in Figure 6 in which the opening 21 is aligned with the outlet of the pipe 20 and its second position P2 illustrated in Figure 7 in which the solid part 22 closes the outlet of the pipe 20.

Thus, the aqueous mineral foam M is directly introduced into the cell after passing through the opening 21.

The displacement of the aqueous mineral foam M through the conveying means 5 is represented by a dotted arrow in FIG.

In this second embodiment, the control means 4 arranged to control the movements of the slide valve 3b can be coupled to a means for controlling the filling level of the cell 101, for example a sensor such as those used in rangefinders of the optical detector type.

Thus, the control means 4 can move the slide valve 3b to its second position P2 only when the aqueous mineral foam M has reached a predetermined height in or slightly above the cell 101.

The pipe 20 and the slide valve 3b can be modulated and replaced by a pipe and a slide valve of different shapes and sizes adapted to fill the cell 101 of another model of the construction element 100.

Of course, the number of lines 20 and slide valves 3b can be adjusted according to the number of cells to be filled.

In this case, the movements of the slide valves 3b can also be synchronized. In a third embodiment illustrated in FIGS. 8 and 9, the regulation means 3 is arranged at the level of the conveying means 5.

In this second embodiment, the conveying means 5 comprises a pipe 30 connected to the storage means 2.

As for the second embodiment, this pipe 30 is sized to give the aqueous mineral foam M an estimated maximum shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 of in order to limit the shearing of the aqueous mineral foam M.

The pipe 30 is intended to open facing the cell 101 of a construction element 100.

The section of the pipe 30 is therefore smaller than the section of the cell 101 so that the aqueous mineral foam M is introduced entirely into the cell 101.

In addition, the pipe 30 is sufficiently flexible to be able to interrupt the flow of the aqueous mineral foam M when the section of the pipe 30 is narrowed.

For this purpose, in this third embodiment the regulating means 3 comprises a narrowing device 3c of the section of the flexible pipe 30.

This narrowing device 3c is preferably arranged at mid-height of the pipe 30 but can also be placed at any height of the flexible pipe 30.

The operating principle of this narrowing device 3c is to clamp the flexible pipe 30 to interrupt the flow of aqueous mineral foam M.

This narrowing device 3c may for example be of the sleeve valve type.

Thus, the constriction device 3c is movable in translation between its first position P1 shown in FIG. 8 in which the constriction device 3c is remote from the flexible conduit 30 and its second position P2 shown in FIG. 9 in which the device of FIG. shrink 3c clamp the pipe 30.

The displacement of the aqueous mineral foam M through the conveying means 5 is represented by a dashed arrow in FIG. 8.

As for the second embodiment, in this third embodiment the control means 4 arranged to control the movements of the clamping device 3c can be coupled to a control means of the filling level of the cell 101, for example a sensor such as those used in rangefinders of the optical detector type.

Thus, the control means 4 can move the constriction device 3c to its second position P2 only when the aqueous mineral foam M has reached a predetermined height located in or slightly above the cell 101.

The pipe 30 and the constriction device 3c can be modulated and replaced by a pipe and a shrink device of different shapes and sizes adapted to fill the cell 101 of another model of the construction element 100.

Of course, the number of conduits 30 and shrink devices 3c can be adjusted according to the number of cells to be filled.

In this case, the movements of the narrowing devices 3c can also be synchronized.

In a fourth embodiment, the routing means 5 comprises a plurality of conduits 30 each connected to the storage means 2.

These conduits 30 are similar to the conduit 30 described above with reference to the third embodiment.

Of course, another means of routing 5 could be envisaged, this means of routing 5 being given here only by way of example to aid in the understanding of the invention.

Each pipe 30 is intended to open facing the cell 101 of a construction element 100 of a series 7 of construction elements 100 arranged on a wooden board 6.

In the example shown, the regulating means 3 comprises a plurality of narrowing devices 3c similar to the narrowing device 3c described above with reference to the third embodiment.

Thus, each shrink device 3c is arranged to interact with a pipe 30 of the plurality of pipes 30.

The movement of these narrowing devices 3c is synchronized with each other so that all the narrowing devices 3c are in their first position P1 or in their second position P2.

This fourth embodiment differs from the third embodiment in that the storage means 2 comprises a closed buffer tank 2a inside which opens a supply line 8 of aqueous mineral foam M. According to a variant illustrated in FIG. 10, the regulating means 3 further comprises shrink devices 3c, a pressure regulating means 3d, for example a vent, disposed on the upper part of the buffer tank 2a.

The supply pipe 8 may comprise several secondary pipes 8 'to ensure a homogeneous distribution of the aqueous mineral foam M inside the buffer tank 2a.

The pressure regulating means 3d has a first so-called open position in which the air contained in the buffer tank can be placed in communication with the air located outside the buffer tank 2a and a second so-called closed position in the air contained in the buffer tank is isolated from the air at. outside the buffer tank 2a.

In addition, the pressure regulating means 3d may also comprise a pressurizing device (not shown), for example a compressed air admission valve, for example 50 mbar or 100 mbar or 200 mbar, connected to the buffer tank 2a.

In use, the aqueous mineral foam M flows continuously through the feed pipe 8 and the secondary pipes 8 'to be deposited on the bottom of the buffer tank 2a.

When the pressure regulating means 3d is in its closed position and the restriction devices 3c are in their second position P2, then during a first pressure increase phase the aqueous mineral foam M is deposited in the bottom of the the buffer tank 2a, which has the effect of increasing the pressure inside the buffer tank 2a.

During this first phase, the cells 101 of one or more construction elements 100 are placed below the pipes 30 by means of relative displacement means between the construction elements 100 and the conveying means 5.

During this first phase, the pressure inside the buffer tank 2a can be adjusted by opening the vent 3d if the actual pressure inside the tank exceeds the set pressure.

Optionally, the pressure inside the buffer tank 2a can be adjusted by opening the compressed air inlet valve if the set pressure is higher than the actual pressure.

During a second withdrawal phase, the constriction devices 3c are brought into their first position P1 and the pressure regulating means 3d remains in its closed position. The pressure generated in the buffer tank 2a during the first phase then makes it possible to release aqueous mineral foam M through the lines 30 until the pressure inside the buffer tank 2a equilibrates with the atmospheric pressure present outside the buffer tank 2a.

In most cases the hydrostatic pressure alone does not generate gravity flow with the use of small diameter pipes, typically less than 50 mm.

It has been empirically found that to generate such a gravity flow through 25 mm diameter pipes, the height of an aqueous M mineral foam having a density of 100 kg / m ³ inside the buffer vessel 2a should be greater than 5 meters, which would considerably increase the size of the buffer tank 2a and limit the possibilities of implementation of the system 1 on existing vibrating presses.

During this second phase of withdrawal, it is also possible to regulate the flow of aqueous mineral foam M leaving the lines 30 by opening the compressed air inlet valve.

The filling of the cavities 101 of the building element or elements 100 can in turn be controlled by the control means, for example a telemeter of the optical detector type which transmits information to the control means 4.

The control means 4 then adjusts the position of each of the narrowing devices 3c of the regulating means 3 in order to obtain a good distribution of aqueous mineral foam M in all the cells 101.

These shrink devices 3c may be of the sleeve valve type.

Then the cycle starts again at the first phase of rise in pressure.

The building elements 100 filled with aqueous mineral foam M are removed by the displacement means and new building elements 100 to be filled are conveyed by these same moving means.

This first phase lasts long enough to allow the storage of a volume of aqueous mineral foam M inside the buffer tank 2a greater than or equal to the volume necessary to fill all the cells 101 of the element or elements of construction 100 during a cycle.

This embodiment therefore makes it possible to adapt the flow rate of mineral foam M passing through the conveying means 5 as a function of the routing rate of the building elements 100 to be filled.

Therefore, the flow rate of mineral foam M passing through the conveyance means 5 depends on the stopping time of the building elements 100 under the conveying means 5, typically between 6 seconds and 10 seconds. Thus, the shorter the dwell time of the building elements 100 under the conveying means 5 is, the more the set point of the pressure regulating means is increased, for example 200 mbar.

On the other hand, the longer the stopping time of the construction elements 100 under the conveying means 5 is, the lower the set point of the pressure regulating means, for example 50 mbar.

In all these embodiments, the number of outlets can be adjusted as a function of the number of cavities 101 to be filled on one and the same construction element 100 or else on different construction elements 100, but also as a function of the dimension of the cell 101.

Of course, the volume of aqueous mineral foam M taken from the storage means 2 is adapted to the volume to be filled.

In addition, this volume in the case of the first embodiment can be filled in one or more cycles of operation.

In a variant illustrated in FIG. 11, in the case where a single pipe 20, 30 or a single injector 11 is arranged for the introduction of the mineral foam M into a cavity 101, then the pipe 20, 30 or, as the case may be, the injector 11 is arranged to be centered on and placed in line with the center 103 of the bottom 102 of the cell 101 of the construction element 100.

However, in another variant illustrated in Figure 12, in the case where several pipes 20, 30 or optionally multiple injectors 11 are arranged for the introduction of the aqueous mineral foam M in a cell 101, in particular in a cell large, then the plurality of pipes 20, 30 or, if appropriate, the plurality of injectors 11 are arranged to be centered on and placed in line with the center 105 of a portion 104 of the bottom 102 of the cell 101 of the construction element 100 whose length results from a division in equal parts of the length L of the bottom 102 of the cell 101 of the construction element 100 in a number of times equal to the number of pipes 20, 30 of the plurality of pipes 20, 30 or possibly the number of injectors 11 of the plurality of injectors 11.

In the example shown in FIG. 12, a construction element 100, for example of the concrete block type, has a single cell 101 with a bottom 102 of length L and width I.

This cell 101 is intended to be filled by two lines 20, 30 or two injectors 11.

Thus, the two lines 20, 30 or the two injectors 11 are arranged in line with the center 105 of each of the two portions 104 resulting from the division in two of the length L of the bottom 102 of the cell 101 of the building element 100. This is a way of homogenizing the distribution of the aqueous mineral foam M inside the cell according to the size of the cell 101.

In another variant illustrated in FIG. 13, in the same case where several pipes 20, 30 or, where appropriate, several injectors 11 are arranged for the introduction of the aqueous mineral foam M into a cell 101, in particular in a cell of large dimension, then the plurality of pipes 20, 30 or if necessary the plurality of injectors 11 are arranged to be centered on and arranged at the points of intersection between a first straight line through the bottom 102 of the cell 101 along its length L and positioned at half its width I and second straight lines d2 transverse to this first straight line through the bottom 102 of the cell 101 over its width I and positioned at a distance from an edge equal to an integer multiple of the ratio between, on the one hand, the length L of the bottom 102 of the cell 101 and, on the other hand, the number of lines 20, 30 plus one.

In the example shown in FIG. 13, a construction element 100, for example of the concrete block type, has a single cell of length L and width I.

This cell 101 is intended to be filled by two lines 20, 30 or two injectors 11.

Thus, the two lines 20, 30 or the two injectors 11 are arranged vertically above the points of intersection between the first line d1 passing through the length L of the bottom 102 on its half-width I and second lines d2 disposed at 1/3 of the length L and 2/3 of the length L starting from a wall of the bottom 102 crossed by the line d1, the numbers 1 and 2 of the numerator of these two fractions corresponding to the integer multiples defined above and the denominator 3 corresponding to the sum of the number of lines 20, which is in this example equal to 2 to which one is added.

This is a second way of homogenizing the distribution of the aqueous mineral foam M inside the cell according to the size of the cell 101.

In general, as illustrated in FIG. 14, the system 1 is arranged to produce a semi-continuous process for introducing a low-density aqueous mineral foam M, in particular a cement foam, into a cavity 101 a construction element 100 comprising the following steps:

(i) having a construction element 100 comprising a cavity 101,

(ii) withdrawing a volume of aqueous mineral foam M from a storage means 2 for the aqueous mineral foam M, (iii) conveying the sampled volume of mineral foam to the cell 101 at a maximum estimated shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 ,

(iv) introducing the collected volume of mineral foam M into the cell 101 of the construction element 100.

The method may comprise a preliminary step in which the aqueous mineral foam M is heated before being introduced into the storage means 2, at a temperature close to the temperature of a hardening chamber otherwise known as a drying oven in which it is intended to dry. construction element 100.

This heating of the aqueous mineral foam M is in particular carried out by heating the water used in the composition of the aqueous mineral foam M.

This step allows an industrial application of the method which can thus be implemented during the manufacturing process of the construction element 100.

Indeed, the aqueous mineral foam M is normally produced at room temperature.

Thus, the final temperature of the aqueous mineral foam M at the outlet of the manufacturing process results, on the one hand, from the temperature of the water used for its manufacture, for example approximately 12 ° C. for a drilling water, and on the other hand proportion of the temperature of the grout, which is slightly warmer than the temperature of the water because at the temperature of the water is added the parameters of the temperature of the cement and the heat resulting from the exothermic chemical reaction of hydration cement.

A construction element 100, for example a concrete block, is produced under the same conditions, therefore at a temperature close to that of the aqueous mineral foam M.

In the industrial manufacturing method of the construction element 100, it is placed in an oven after its cells 101 have been filled with aqueous mineral foam M.

The oven has a temperature higher than that of the ambient air, about 10 ° C more.

However, since the mineral foam M is composed of approximately 92% of air, then a temperature rise of 10 ° C. of a volume of mineral foam M results in an increase in the volume of the mineral foam M by approximately 3%.

This increase in volume occurs in all directions and therefore the mineral foam M applies a stress on the walls of the cell 101 of the construction element 100 in the fresh state, thus causing its deformation and rendering it unusable. The heating of the water during the manufacture of the aqueous mineral foam M makes it possible to reduce the temperature difference between the aqueous mineral foam M introduced into the cavities 101 of the construction element 100 and the temperature of the oven in which is intended to dry the construction element 100.

Thus, the construction element 100 is no longer deformed because the expansion of the mineral foam M is limited.

Furthermore, it should be noted that this semi-continuous process can also be used for the introduction of an aqueous mineral foam M into a cavity 101 of a construction element 100 in the cured state.

For this, it is sufficient to perform a preliminary step of wetting the construction element 100 until the capillary water absorption coefficient of the construction element 100 at 10 minutes is less than 5 g / (m ² .s), preferably less than 4 g / (m ² .s), even more preferably less than 3 g / (m ² .s).

Indeed, the cured construction elements 100 are generally very porous and part of the water contained in the aqueous mineral foam M during the introduction into the cell 101 is absorbed by the construction element 100, which destabilizes the mineral foam M and results in a detachment of the mineral foam M at the interface with the walls of the cell 101 the building element 100.

The inventors have found in tests that wetting the construction element 100 in the cured state until the capillary water absorption coefficient of the construction element 100 at 10 minutes less than 5 g / (m ² · s), preferably less than 4 g / (m ² · s), still more preferably less than 3 g / (m ^z · s), limited this water absorption and preserved the sought qualities of the mineral foam M.

The volume of aqueous mineral foam M to fill one or more cavities 101 of the construction element 100 is greater than the cumulative volume of the one or more cavities 101 to be filled.

The aqueous M mineral foam thus exceeds beyond the maximum height of the cell 101.

This makes it possible to compensate for the removal of the mineral foam M and thus makes it possible to obtain a cell 101 entirely filled with mineral foam M.

Thus, the method may comprise a subsequent step of grinding the face of the building element 100 by which the aqueous mineral foam M has been introduced into the cell 101 of the building element 100.

This step is carried out after drying of the mineral foam M and of the construction element 100 in the fresh state in which the aqueous mineral foam M has been introduced, or after the drying of the mineral foam M of the element of construction 100 in the cured state in which the aqueous mineral foam M has been introduced.

Thus, a ready-to-use construction element 100 such as the concrete block illustrated in FIG. 15 is obtained.

Although the invention has been described in connection with particular embodiments, it is obvious that it is not limited thereto and that it includes all the technical equivalents of the means or steps described and their combinations.

Examples:

Table 1 below gives three examples of possible configurations for the first embodiment described above in the description and comprising an intermediate chamber 10, an injector 11, a movable piston 12, a T-flange connection 15 and a pipe 16 connecting the piston 12 to the flange connection T 15.

Each configuration is suitable for filling cells having a volume of 10.2 L for the first configuration and 12 L for the second and third configuration.

For constant diameters of the pipe 16, the injector 11 and the chamber 10, it is noted that the longer the dosing time and the more the estimated shear rate in the chamber 10, the pipe 16 and the injector 11 is weak.

Table 1: Example of configurations for the embodiment with a piston Table 2 below shows two examples of possible configurations for the embodiment mentioned above in the description and comprising a worm having a first operating state, for example the operating state that allows to dose the volume. aqueous mineral foam M to be withdrawn from the storage means 2, and a second operating state, for example the stopping state which makes it possible to interrupt the flow of the aqueous mineral foam M outside the storage means 2.

Note on this table that it can be considered to adapt the sizing of the worm according to the volume of the cell 101 to fill.

On the other hand, it is noted that the smaller the passage section of the conveying means 5 is, the more it is necessary to reduce the rotational speed of the worm to maintain a small value of the estimated shear rate in the injector 11 .

Configuration Configuration

1 2

Duration of the first state of

8

operation in s

Volume of a cell 101 in Liter

Outside diameter of turns in

80 50

mm

Diameter of the shaft in mm 20

No turns in mm 80 75

Speed of rotation of the worm

239 103

in rpm

Cross section in m ² 4,71E-03 l, 94E-03

Estimated shear velocity

1,01 0.74

in the injector 11 in s ¹

Table 2: Example of configurations for an embodiment with a screw

unending Table 3 below shows two examples of possible configurations for the second embodiment mentioned above in the description and comprising a pipe 20 connected to the storage means 2 and wherein the regulating means 3 comprises a slide valve 3b adjacent to the outlet of the pipe 20, the pipe 20 being intended to open facing the cell 101 of the construction element 100.

Note from this table that in this embodiment that even with very short dosing times, the estimated shear rates are very low.

Table 3: Example of configurations for the second embodiment with a slide valve

Table 4 below illustrates four different configurations in which the flow of aqueous mineral foam M passing through the conveying means 5 is identical.

This aqueous mineral foam flow rate M is determined and adjusted empirically by measuring the volume of aqueous mineral foam M that has flowed through the conveyor means 5 in one minute.

This table 3 confirms that at a constant flow rate, the greater the diameter of the pipe used as the conveyance means 5 increases the more the average flow rate of the aqueous mineral foam M through this pipe decreases.

However, this table highlights the large differences in values for the estimated shear rate in these pipes.

It is then noted that there is a correlation between the value of this estimated shear rate and the stability of the aqueous mineral foam M.

Table 4: Estimated shear rate of the aqueous mineral foam M as a function of the average flow rate

Claims

System (1) for introducing a low density aqueous mineral foam (M), in particular a cement foam, into a cell (101) of a building element (100), in particular in a cell of a block Masonry, including:

means for storing (2) the aqueous mineral foam (M),

a means (3) for regulating the flow of the aqueous mineral foam (M) from the storage means (2) towards the outside of the storage means (2), said regulating means (3) being movable between a first position (P1) or a first operating state in which the flow of the aqueous mineral foam (M) is allowed and a second position (P2) or a second operating state in which the flow of the mineral foam ( M) is interrupted,

control means (4) arranged to control the movement of the regulating means (3) so as to take a volume of aqueous mineral foam (M) from the storage means (2),

means for conveying (5) the aqueous mineral foam (M) disposed between the storage means (2) and the cell (101) of the construction element (100), the conveying means (5) ) being dimensioned to give the aqueous mineral foam (M) a maximum estimated shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 .

System (1) according to claim 1, wherein the control means (4) is arranged to control the movement of the regulating means (3) so that the volume of the aqueous mineral foam (M) is greater than or equal to the volume necessary to fill the cell (101) of the construction element (100). System (1) according to one of claims 1 or 2, wherein the control means (4) is connected to a means for controlling the filling level of the cell (101).

System (1) according to one of claims 1 to 3, comprising relative displacement means between the construction element (101) and the conveying means (5).

System (1) according to one of claims 1 to 4, wherein the conveying means (5) comprises:

an intermediate chamber (10) disposed downstream of the regulating means (3) and arranged to receive the extracted volume of aqueous mineral foam (M), an injector (11) intended to be arranged opposite the cell (101),

a piston (12) movable in the intermediate chamber (10) between a first position (P1) in which the volume of the intermediate chamber (10) is maximum and a second position (P2) in which the volume of the intermediate chamber ( 10) is minimal, the passage from the first position (P1) to the second position (P2) being intended to push the extracted volume of aqueous mineral foam (M) present in the intermediate chamber (10) towards the injector (11) .

6. System (1) according to claim 5, wherein the injector (1) comprises a valve (13) movable between a first position (P1 ") in which the flow of the aqueous mineral foam (M) is authorized and a second position (P2 ") in which the flow of the aqueous mineral foam (M) is interrupted.

7- System (1) according to one of claims 5 or 6, wherein the injector (1) comprises an inverted valve having a base wider than its top.

8- System (1) according to one of claims 5 to 7, wherein the control means (4) is further arranged to control the movements of the piston (12) and optionally the movements of the valve (13) of the injector (11).

9- System (1) according to one of claims 5 to 8 wherein the movements of the control means (3), the piston (12) and optionally the valve (13) of the injector (11) are defined according to several predefined operating phases in which these movements are performed sequentially and cyclically.

10- System (1) according to one of claims 5 to 9, wherein the control means (3) comprises a valve, preferably a butterfly valve (3a) or a sleeve valve.

11- System (1) according to one of claims 1 to 4, wherein the conveying means (5) comprises a pipe (20) connected to the storage means (2) and the regulating means (3) comprises a slide valve (3b) adjoining the outlet of the pipe (20), the pipe (20) being intended to open facing the cell (101) of the construction element (100).

12- System (1) according to one of claims 1 to 4, wherein the conveying means (5) comprises a pipe (30) connected to the storage means (2), said pipe (30) being intended to unclog opposite the cell (101) of the construction element (100) and said pipe (30) being sufficiently flexible to be able to interrupt the flow of the aqueous mineral foam (M) when the section of the pipe (30) is narrowed. 13- System (1) according to claim 12, wherein the regulating means (3) comprises a device for narrowing (3c) the section of the pipe (30) flexible.

14- System (1) according to one of claims 12 or 13, wherein the storage means (2) comprises a closed buffer tank (2a) and the control means (3) further comprises a pressure regulating means (3d) disposed on the buffer tank (2a).

15- System (1) according to one of claims 5 to 14, wherein:

a single pipe (20, 30) or, where appropriate, a single injector (11) is arranged for introducing the aqueous mineral foam (M) into a cell (101), in this case the pipe (20, 30). or where appropriate the injector (11) is arranged to be centered on and placed in line with the center (103) of the bottom (102) of the cell (101) of the construction element (101), or

several pipes (20, 30) or, where appropriate, several injectors (11) are arranged for introducing the aqueous mineral foam (M) into a cell (101), in this case the plurality of pipes (20, 30). or where appropriate the plurality of injectors (11) are arranged to be centered on and arranged in alignment:

- the center (105) of a portion (104) of the bottom (102) of the cell (101) of the construction element (100) whose length results from a division in equal parts of the length (L ) of the bottom of the cell (101) of the construction element (100) in a number of times equal to the number of pipes (20, 30) of the plurality of pipes (20, 30) or, if appropriate, to the number injectors (11) of the plurality of injectors (11), or

points of intersection between a first straight line (d1) crossing the bottom (102) of the cell (101) along its length (L) and positioned at half of its width (I) and second lines (d2) transverse to this first straight line (d1) passing through the bottom (102) of the cell (101) over its width (I) and positioned at a distance from an edge equal to an integer multiple of the ratio between the length on the one hand (L) of the bottom (102) of the cell (101) and secondly the number of conduits (20, 30) plus one.

16- System (1) according to one of claims 1 to 15, comprising a rinsing device of the conveying means (5) arranged to clean the residual mineral foam (M) possibly present in the distribution means (5) .

17- A semi-continuous process for introducing a low density aqueous mineral foam (M), in particular a cement foam, into a cell (101) of a building element (100) comprising the following steps:

- have a construction element (100) comprising a cell (101), - withdrawing a volume of aqueous mineral foam (M) from a storage means (2) of the aqueous mineral foam (M),

conveying the collected volume of aqueous mineral foam (M) to the cell at a maximum estimated shear rate of 55 s ^-1 , preferably 30 s ^-1 , and even more preferably 5 s ^-1 ,

- Introduce the collected volume of aqueous mineral foam (M) in the cell (101) of the construction element (100).

18- The method of claim 17, wherein the steps are carried out from a system (1) for introducing an aqueous mineral foam (M) into a cell (101) of a construction element (100) according to the one of claims 1 to 16.

19- Method according to one of claims 17 or 18, comprising a prior step in which the mineral foam (M) is heated before being introduced into the cell (101) of the construction element (100), the heating temperature being close to the temperature of a hardening chamber in which is intended to dry the construction element (100).

20- The method of claim 19, wherein the heating of the mineral foam (M) is achieved by heating the water used for the manufacture of the mineral foam (M).

21- Method according to one of claims 17 to 20, wherein the construction element (100) is in the fresh state.

22- Method according to one of claims 17 to 20, wherein the construction element (100) is in the cured state, the method then has a prior step of wetting the construction element (100) up to the water absorption coefficient of the building element (100) at 10 minutes is less than 5 g / (m ² · s), preferably less than 4 g / (m ² · s), more preferably still less than 3 g / (m .s).

23- Method according to one of claims 17 to 22, wherein the volume of aqueous mineral foam (M) is greater than the volume of the cell (101) to be filled with the construction element (100) or the volume of aqueous mineral foam (M) is greater than the sum of the volumes of cells (101) to be filled with the construction element (100).

The method of claim 23 comprising a subsequent step of grinding a face of the building element (100) by which the aqueous mineral foam (M) has been introduced into the cell (101) of the construction (100), this step being carried out after the drying of the mineral foam (M) and the construction element (100) in the fresh state in which the aqueous mineral foam (M) was introduced, or after drying of the mineral foam (M) of the construction element (100) in the cured state in which the aqueous mineral foam (M) was introduced.

25- Element of construction (100) comprising one or more cells (101), wherein the cell or cells comprise low density mineral foam (M) introduced following the implementation of the introduction method according to one or more Claims 17 to 24.

26. Construction element according to claim 25, wherein the construction element (100) is a masonry block, in particular a concrete block or a brick.