Shaped composite comprising a mineral wool

Abstract

The present invention relates to a method for producing a shaped composite, comprising: i) preparing a mixture comprising: at least 30% by weight of recycled mineral wool material comprising an adhesive comprising a phenolic resin, 11 to 25% by weight of hydraulic binder comprising clinker at a content of between 30% and 90% by weight, mineral fillers, and water; and ii) shaping the mixture into a shaped composite. The invention further relates to a shaped composite that can be obtained by a method of this kind, and to a method for producing a mineral wool using a shaped composite of this kind.

Description

[0001] Shaped composite comprising mineral wool

[0002] The invention relates to the field of the recovery of mineral wool-based residues, in particular rock wool or glass wool. Usually, mineral wool production residues are agglomerated in the form of shaped composites, frequently referred to as "briquettes" (other names being available essentially depending on the geometry of the shaped composite) to be recycled in the mineral wool manufacturing process. These shaped composites, in particular in the form of briquettes, can be introduced into a melting furnace, which itself feeds a fiberizing device.

[0003] According to a process called external centrifugation, mineral wool is obtained from a molten mineral mass poured onto a set of rotating rotors, the molten mass being ejected from the periphery of the rotors and taken up by a gaseous drawing current and thus transformed into fibers. The wool is then impregnated with a sizing composition. The sizing composition is sprayed onto the fibers during their formation and then the mass of sized fibers is collected on a receiving member and conveyed into a device for shaping a strip of mineral wool felt. The sizing is intended to give cohesion to the wool by forming bridges between the fibers after cooking and crosslinking.This process produces a significant amount of residue, firstly during fiberization, where residues include solidified mineral matter and sizing, said solidified mineral matter generally including fibers and grains ("shot" in English); and secondly after formation of the felt following cuts intended to rectify the edges of the felt or to size the products. Finally, it happens that production does not provide the expected quality and some batches are discarded.

[0004] According to another process, called internal centrifugation, the molten material is this time fiberized through a fiberizing member in the form of a plate pierced at its periphery, the material being ejected through the pierced wall of the plate in the form of filaments which are drawn by a gaseous drawing current. This technique produces a fiberizing yield much higher than the external centrifugation technique and does not produce grains. However, cutting waste is unavoidable. These mineral-based residues can be recovered in the mineral wool manufacturing circuit, in particular by remelting with the raw materials feeding the melting furnace. This recycling generally involves the preparation of composites containing these residues, said composites being produced by conformation, in particular molding, of a mixture of mineral wool residues with a mineral binder, followed by a treatment ensuring the setting of the binder.The shaping of briquettes makes it easy to transport these residues and facilitates their reuse process, in particular their reintroduction into a melting furnace.

[0005] In the case of rock wool, this furnace may be of the cupola type, in which the charge of solid raw material made from blocks of natural rock forms, with blocks of solid fuel (coke) in alternating layers, a self-supporting column through which the combustion gases escape. As melting takes place in the lower part of the column, the latter is recharged from the top with fuel and rock. These furnaces do not allow the introduction of raw materials in powder or light particles which do not have the required ability to form a layer of stable solid material in the vertical column. Transformation into a shaped composite such as a briquette provides this ability. The aim is for the briquette to develop good mechanical strength fairly quickly after its shaping and for it not to disintegrate during handling and transport.

[0006] To achieve good mechanical strength, high levels of hydraulic binders, which themselves have high clinker contents, are generally used. However, such briquettes are not satisfactory from an environmental point of view. The use of clinker contributes significantly to greenhouse gas emissions, particularly CO2 and SO X There is therefore a real need to develop briquettes whose composition has a reduced environmental impact, but which retain good mechanical resistance and remain fibrable (for example by external centrifugation).

[0007] SUMMARY OF THE INVENTION

[0008] In this context, the inventors have surprisingly demonstrated that the hydraulic binder content and the clinker content in this hydraulic binder could be significantly reduced when mineral wool recyclates comprising a phenolic resin-based sizing were used, without affecting the mechanical strength of the briquette. The composition of the briquettes developed also allows them to be fiberized (for example by external centrifugation).

[0009] Thus, the present invention relates to a method for manufacturing a shaped composite, comprising: i) preparing a mixture comprising:

[0010] - at least 30% by weight of mineral wool recyclates comprising a sizing comprising a phenolic resin,

[0011] - 11 to 25% by weight of hydraulic binder comprising clinker in a content of between 30 and 90% by weight,

[0012] - mineral fillers, and

[0013] - water; and ii) conforming said mixture into a shaped composite.

[0014] In some embodiments, the hydraulic binder further comprises 10 to 50% by weight of one or more non-cementitious silica carriers distinct from the mineral wool.

[0015] In some embodiments, said non-cementitious silica carriers are selected from an alkali silicate, calcined or natural clay, kaolinite, illite, montmorillonite, calcined kaolin, dehydrated kaolin, silica fume, class C or F fly ash, biomass ash, blast furnace slag, steel mill slag, rice hull ash, rice husk, pozzolan, volcanic ash, diatomite, and a mixture of at least two thereof.

[0016] In some embodiments, the hydraulic binder comprises silica fume, preferably in a content of 5 to 15% by weight relative to the total dry weight of the hydraulic binder.

[0017] In some embodiments, the mineral wool recyclates comprise rock wool recyclates, glass wool recyclates, or a mixture thereof.

[0018] In some embodiments, the mineral wool recyclate content is 40 to 60% by weight, based on the total dry weight of the mixture.

[0019] In some embodiments, the sizing is present in the mineral wool recyclates at a rate of 0.1 to 10% by weight, and more particularly at a rate of 0.5 to 7% by weight of sizing solids relative to the total weight of dry mineral wool recyclates. In some embodiments, the phenolic resin is present in the sizing at a rate of 50 to 90% by weight of the sizing solids.

[0020] In certain embodiments, the weight content of mineral fillers is between 5% and 60% by weight, preferably between 30% and 60%, relative to the total dry weight of the mixture.

[0021] In some embodiments, the mineral fillers are selected from gravel, inert slag, and a mixture thereof.

[0022] In certain embodiments, the hydraulic binder represents from 11 to 20% by weight, preferably from 11 to 15% by weight, or even from 12 to 14% by weight, of the total dry weight of the mixture.

[0023] In some embodiments, the hydraulic binder comprises clinker in a content of between 30% and 80% by weight.

[0024] The present invention also relates to a shaped composite formed from a mixture comprising:

[0025] - at least 30% by weight of mineral wool recyclates comprising a sizing comprising a phenolic resin,

[0026] - 11 to 25% by weight of hydraulic binder comprising clinker in a content of between 30 and 90% by weight,

[0027] - mineral fillers, and

[0028] - water.

[0029] More particularly, the present invention relates to a shaped composite obtainable by the method as defined in the present application.

[0030] Another object of the present invention is a method of manufacturing a mineral wool, comprising:

[0031] - a step a) of feeding a melting chamber, such as a cupola furnace, with a shaped composite as defined in the present application, as a vitrifiable charge, and

[0032] - a step b) of melting said shaped composite in said melting chamber, to obtain a bath of molten material, and

[0033] - a step c) of fiberizing said bath of molten material. DETAILED DESCRIPTION

[0034] Step i) of the process according to the invention comprises the formation of a mixture comprising:

[0035] - at least 30% by weight of mineral wool recyclates comprising a sizing comprising a phenolic resin,

[0036] - 11 to 25% by weight of hydraulic binder comprising clinker in a content of between 30 and 90% by weight,

[0037] - mineral fillers, and

[0038] - water.

[0039] The weight content of mineral wool recyclates and hydraulic binder are dry weight contents expressed in relation to the total dry weight of the mixture. The content of clinker (and other components of the hydraulic binder described below) in the hydraulic binder is a dry weight content expressed in relation to the total dry weight of the hydraulic binder.

[0040] In this application, the expression "mineral wool recyclates" means all residues from the production of mineral wool, including solidified mineral materials in the form of grains or fibers, or recovered in the form of solid flakes, or bundles of fibers recovered (by washing) on ​​the various receiving or conveying surfaces, as well as cut mineral wool felt. Mineral wool recyclates may optionally be in the form of slightly crushed fibers (but retaining a fibrous character). Mineral wool recyclates are typically in the form of fibers longer than 5 mm.

[0041] Mineral wool recyclates may in particular be recyclates of rock wool, glass wool (including in particular low alumina and high alumina glass wool), or a mixture of these.

[0042] For the purposes of the invention, a mineral wool has a chemical composition comprising the following constituents:

[0043] SiO2: 30 to 75% by mass, CaO+MgO: 5 to 45% by mass, AI2O3: 0 to 30% by mass, Na2O+K2O: 0 to 20% by mass, Fe2O3: 0 to 20% by mass, B2O3: 0 to 14% by mass, MnO: 0 to 4% by mass. The term rock wool generally refers to mineral wools with fibers whose chemical composition includes the following constituents:

[0044] SiO2: 30 to 50% by mass, AI2O3: 10 to 22% by mass, CaO+MgO: 20 to 45% by mass, Fe2O3: 0 to 20% by mass, Na2O+K2O: 0 to 10% by mass, B2O3: 0 to 1% by mass.

[0045] In contrast, the term glass wool generally refers to mineral wools with fibers whose chemical composition includes the following constituents:

[0046] - For so-called low alumina glass wools:

[0047] SiO2: 50 to 75% by mass, AI2O3: 0 to 8% by mass, CaO+MgO: 5 to 20% by mass, Fe2O3: 0 to 3% by mass, Na2O+K2O: 6 to 20% by mass, B2O3: 0 to 14% by mass, MnO: 0 to 4% by mass.

[0048] - For so-called high alumina glass wools:

[0049] SiO2: 35 to 55% by mass, AI2O3: 16 to 27% by mass, CaO+MgO: 3 to 30% by mass, Fe2O3: 0 to 15% by mass, Na2O+K2O: 5 to 17% by mass, B2O3: 0 to 5% by mass.

[0050] The mineral wool compositions are herein expressed in oxide form by convention. In particular, if the (total) iron oxide content is expressed in the form Fe2O3, this does not mean that this iron oxide is necessarily and exclusively present in the ferric form. Iron oxide can be present in both its ferric (Fe2O3) and ferrous (FeO) forms, and it is purely by convention that the total iron oxide content is designated by Fe2O3. Preferably, the sum of the mass concentrations of SiO2, AI2O3, CaO, MgO, Fe2O3, Na2O, K2O and MnO in the mineral wool compositions described above is greater than or equal to 90%, or even greater than or equal to 95%.

[0051] Mineral wool recyclates include a sizing comprising a phenolic resin. The sizing is typically present in mineral wool recyclates at a rate of 0.1 to 10% by weight, and more particularly at a rate of 0.5 to 7% by weight of dry sizing matter relative to the total weight of dry mineral wool recyclates.

[0052] The sizing containing the phenolic resin generally contains the latter in an amount of 50 to 90% by weight, preferably 70 to 90% by weight, of the dry matter of the sizing (% of dry phenolic resin on the total weight of dry sizing). Sizings based on phenolic resins are well known to those skilled in the art. Phenolic resin (also called "resol") is a thermosetting resin typically obtained by condensation of phenol and formaldehyde. Other constituents may be added to the phenol and formaldehyde, in particular to adjust the properties of the resin. These constituents may, for example, be glycine, urea, an amine, or an amino alcohol. Alternatively, the aforementioned constituents may be added to the sizing composition comprising the phenolic resin (i.e., after formation of said phenolic resin).

[0053] Phenolic resin can also be formed in the presence of a crosslinkable thermoplastic homopolymer or copolymer (e.g. acrylic resins, poly(vinyl acetates), polyurethanes and their homo- and copolymers, in particular copolymers based on acrylic acid esters also using acrylonitriles).

[0054] Generally, the sizing also comprises other components than the phenolic resin. It may in particular comprise a catalyst (e.g. ammonium sulfate or sulfamate), a coupling agent (e.g. a silane, more particularly an aminosilane), a water-repellent agent (e.g. a silicone), an anti-dust agent (e.g. an oil), a hydrophobic agent, a polycondensation retarder (e.g. ammonia), a stabilizer (e.g. metal oxide nanogels, glass particles), a flame retardant (e.g. ammonium phosphates or polyphosphates), clays (in particular kaolinites, montmorillonites, kaolin and / or bentonite), a thixotropic agent (e.g. polysaccharides such as starch, potato starch, polysaccharide derivatives such as methylcellulose), or pigment dispersers.

[0055] In a particular mode, the gluing includes:

[0056] - from 50 to 90% by weight, preferably from 70 to 90% by weight, of phenolic resin,

[0057] - from 5 to 30% by weight, preferably from 10 to 20% by weight, of urea,

[0058] - from 0.01 to 5% by weight, preferably from 0.5 to 2% by weight, of catalyst (eg a sulfate),

[0059] - from 0.01 to 2% by weight, preferably from 0.1 to 1% by weight, of retarder (eg ammonium),

[0060] - from 0.001 to 1% by weight, preferably from 0.01 to 0.5% by weight, of coupling agent (eg silane), these contents being expressed in dry weight relative to the total dry weight of the sizing.

[0061] The concentration of dry extracts in the sizing is generally between 5 and 40%, preferably between 10% and 20%.

[0062] By way of illustration of documents describing phenolic resin-based sizing compositions, the following documents, incorporated by reference, may be cited: EP2609129, EP2091986, EP1289901, and EP1551892.

[0063] The sizing comprising the phenolic resin is preferably non-thermoset. However, in some embodiments, the sizing is in its thermoset form. The term "thermoset" refers to a sizing in an insoluble and infusible form, typically obtained by heating the sizing. In some embodiments, the mixture comprises both mineral wool recyclates comprising a non-thermoset sizing and mineral wool recyclates comprising a thermoset sizing.

[0064] The mineral wool recyclates comprising the sizing comprising the phenolic resin represent at least 30% by weight, in particular at least 35% by weight, preferably from 40% to 60% by weight, for example from 40% to 50% by weight, relative to the total dry weight of the mixture (percentages of dry mineral wool recyclates).

[0065] The hydraulic binder represents from 11 to 25% by weight, for example from 11 to 20%, or from 11 to 15%, in particular from 12 to 14% by weight, of the total dry weight of the mixture. The hydraulic binder comprises clinker in a weight content of between 30% and 90% by weight, preferably between 30% and 80% by weight, for example between 40% and 60% by weight, or between 65% and 80% by weight (i.e. relative to the total dry weight of the hydraulic binder). The clinker is a mixture of silicates (in particular, tricalcium silicate and dicalcium silicate) and aluminates (in particular, tricalcium aluminate and tetracalcium aluminoferrite). The clinker generally has a D50 of less than or equal to 200 pm, preferably less than or equal to 100 pm, in particular less than or equal to 50 pm. The clinker generally has a D90 of less than or equal to 100 pm, in particular from 0.2 to 100 pm.The hydraulic binder generally further comprises one or more non-cementitious materials, advantageously in a content of between 10% and 70% by weight, preferably between 20% and 70% by weight, for example between 40% and 60% by weight, or between 20% and 35% by weight (i.e. relative to the total dry weight of the hydraulic binder). Typically, the sum of the weight of non-cementitious materials and the weight of clinker makes up 100% of the weight of the dry hydraulic binder.

[0066] The term "non-cementitious" indicates that the compound to which it is attached is not a cement. A cement is in particular a cement as defined by standard NF EN 197-1 and by standard NF EN 197-5. A cement is in particular:

[0067] - an anhydrous powdered material comprising crystallized calcium silicate or crystallized calcium aluminate,

[0068] - a hydraulic mineral compound leading to the formation in the presence of water of hydrated calcium silicate or hydrated calcium aluminate, and

[0069] - essentially crystalline and contains less than 10% by weight of amorphous.

[0070] In addition, cement includes clinker, which is produced through a clinkerization process.

[0071] In a cement, calcium silicate or calcium aluminate are crystalline phases. A slag and an alkali silicate are not considered by the skilled person to be cements.

[0072] In a preferred embodiment, said non-cementary material comprises one or more non-cementary silica carriers, distinct from the mineral wool. In such an embodiment, the hydraulic binder may comprise from 10% to 50% by weight, in particular from 15% to 45% by weight, of one or more non-cementary silica carriers, distinct from the mineral wool (i.e. relative to the total dry weight of the hydraulic binder).

[0073] The non-cementary silica carrier refers to a material having hydraulic properties, which forms silicate ions in the presence of water. The non-cementary silica carrier may optionally have a crystalline character if it dissolves easily in water. This is the case in particular for a sodium silicate, which may in particular be introduced into the mixture in the form of an aqueous solution. On the other hand, if a slag is used as a non-cementary silica carrier, it is preferably appropriate for it to be amorphous at more than 80% by weight and even more preferably at more than 90% by weight, for it to comprise at least 10% by weight of silica, and for it to have a fine particle size, in particular such that its D50 is less than or equal to 200 μm, preferably less than or equal to 100 μm and even more preferably less than or equal to 50 μm. Such slags can be obtained as by-products of the steel industry.They derive their vitreous structure, i.e. their essentially amorphous character, from the water quenching treatments applied to them after collection, which gives them latent hydraulic properties. When dry, the non-cementitious silica carrier is preferably a totally or partially amorphous mineral solid compound. It is preferably more than 80% amorphous by weight and more preferably more than 90% amorphous by weight. It preferably comprises at least 10% by weight of silica (SiC>2) and more preferably at least 20% by weight of silica. It optionally comprises alumina. It may contain, in smaller quantities, iron oxide, alkali metal oxide, alkaline earth metal oxide, a phosphate, a sulfate, a sulfide, titanium oxide. It is preferably sufficiently fine to dissolve at least partially in an aqueous medium.Thus, the particle size of the non-cementitious silica carrier is preferably such that the D50 is less than or equal to 200 pm, preferably less than or equal to 100 pm and even more preferably less than or equal to 50 pm. In glass applications, this silica carrier is a source of SiCh in the final glass.

[0074] The non-cementitious silica carrier may in particular be chosen from: an alkali silicate, a calcined or natural clay, kaolinite, illite, montmorillonite, calcined kaolin or dehydrated kaolin such as mainly amorphous metakaolin which may contain kaolinite crystals, silica fume, fly ash (e.g. class C or class F), biomass ash, slag (e.g. blast furnace slag, steelworks slag), rice husk ash, rice husk, pozzolan (e.g. calcined natural or synthetic pozzolan), natural or calcined volcanic ash, diatomite, or a mixture of at least two of these.

[0075] It is preferred that the non-cementitious silica carrier be a slag (e.g. blast furnace slag), a pozzolan (e.g. natural or synthetic calcined), silica fume, or a mixture of at least two of these.

[0076] A slag is a by-product of the steel industry and generally has a SiO2 / CaO ratio (by weight) < 1.5 and the sum of its CaO and SiO2 content represents more than 45% of its weight. In a particular embodiment, the hydraulic binder comprises silica fume, preferably in a content of 5% to 15% by weight, for example 6% to 12% by weight (i.e. relative to the total dry weight of the hydraulic binder).

[0077] In a more particular embodiment, the hydraulic binder comprises (relative to the total dry weight of the hydraulic binder):

[0078] - 5% to 15% by weight, for example 6% to 12% by weight of silica fume, and

[0079] - 10% to 50% by weight, for example 15% to 45% by weight of pozzolan or blast furnace slag.

[0080] Said non-cementitious material may further comprise one or more non-cementitious alkaline-earth carriers (i.e. distinct from the mineral wool and distinct from the non-cementitious silica carrier). In such an embodiment, the hydraulic binder may comprise from 1% to 25% by weight, in particular from 10% to 20% by weight, of one or more non-cementitious alkaline-earth carriers (i.e. distinct from the mineral wool and distinct from the non-cementitious silica carrier), relative to the total dry weight of the hydraulic binder.

[0081] The non-cementary alkaline earth carrier contains an alkaline earth and forms alkaline earth ions in the presence of water. It preferably comprises at least 10% by weight of alkaline earth (this is the % of the alkaline earth element such as Ca or Mg, and not the percentage of its oxide) and preferably at least 20% by weight of alkaline earth. The non-cementary alkaline earth carrier may be chosen from limestone or chalk (CaCO1), quicklime CaO or slaked lime Ca(OH)2, magnesian lime or dolomite (CaMgfCChh), aragonite, vaterite or other polymorphs of CaCO1, or a mixture of at least two of these, preferably limestone.

[0082] The particle size of the non-cementitious alkaline earth carrier has a particle size preferably such that the D50 is less than or equal to 200 pm, preferably less than or equal to 100 pm and even more preferably less than or equal to 50 pm. In glass applications, this alkaline earth carrier is a source of alkaline earth oxide (in particular CaO or MgO) in the final glass.

[0083] Preferably, the non-cementitious alkaline-earth carrier does not comprise any other metals (e.g. alkali, transition metals, etc.) or metalloids (e.g. silicon) than the alkaline-earth. Said non-cementitious material of the hydraulic binder may further comprise additives (or equivalently “addition elements”). These additives are well known to those skilled in the art. They are conventionally chosen from gypsum and organic adjuvants (e.g. plasticizers, air-entrainers, water-retaining agents).

[0084] These additives generally represent less than 5% by weight of the hydraulic binder (i.e. relative to the total dry weight of the hydraulic binder).

[0085] In general, all the constituents of the hydraulic binder have a D50 less than or equal to 200 pm, preferably less than or equal to 100 pm and even more preferably less than or equal to 50 pm.

[0086] Said mixture also comprises mineral fillers. These mineral fillers may be chosen from inert mineral materials (in particular with respect to the binder of the composite). The mineral fillers may be aggregates useful for the mechanical stability of the shaped composite or components useful for the vitrifiable charge with a view to recovery in glass melting, in particular for its iron content. The aggregates generally have a D50 greater than 200 pm, in particular greater than 500 pm, or even greater than 1 mm.

[0087] In a particular mode, the mineral fillers are chosen from gravel, inert slag (or equivalently “non-reactive slag”), and a mixture of these.

[0088] More specifically, it may be aggregates from industrial recycling channels recovering industrial by-products (or co-products) or from the demolition of buildings or roads (concrete crush, bricks, recycling of railway ballast, crusts or millings from road surfaces or mining spoil heaps). Inert slag as a mineral filler is coarse and is not considered to be a carrier of non-cementitious silica in the sense given above, because it does not particularly form silicate ions in the presence of water and is also crystalline at more than 20% of its weight and has a large particle size with a median diameter D50 greater than 50 pm, for example a D50 greater than 200 pm, in particular greater than 1 mm. The same applies to gravel. These may include LD slags from converters, which are solidified without quenching treatment after collection, whereby they crystallize.This mineral filler, inert insofar as it does not participate in the chemistry of the solidification of the shaped composite, is nevertheless a source of raw material for the mineral fiber which will be manufactured when the shaped composites are reused for fusion.

[0089] Preferably, the mineral fillers are constituents (e.g. aggregates) with a D50 greater than 200 pm, or even greater than 500 pm, or even greater than 1 mm.

[0090] More preferably, the mineral fillers are chosen from gravel, inert slag (or equivalently “non-reactive slag”), and a mixture thereof, where said gravel and said inert slag each independently have a D50 greater than 200 pm, or even greater than 500 pm, or even greater than 1 mm.

[0091] The weight content of mineral fillers is advantageously between 5% and 60% by weight, preferably between 30% and 60%, more particularly between 40% and 55% by weight, relative to the total dry weight of the mixture.

[0092] Typically, mineral wool recyclates (including sizing comprising a phenolic resin), hydraulic binder and mineral fillers together represent at least 90%, in particular at least 95%, or even at least 98%, or even at least 99% of the total dry weight of the mixture.

[0093] In some embodiments, the mixture is such that:

[0094] - all the constituents having a D50 less than or equal to 200 pm (preferably less than or equal to 100 pm and even more preferably less than or equal to 50 pm) constitute the hydraulic binder; and

[0095] -all constituents with a D50 greater than 200 pm (or even greater than 500 pm, or even greater than 1 mm) constitute mineral fillers.

[0096] The mixture for preparing the molding mass can be made in any suitable mixer. It is generally unnecessary to heat the mixture by adding calories from outside the mixture. The temperature of the mixture may rise due to the solubilization of certain ingredients. Water is introduced in sufficient quantity for the hydraulic binder to be distributed throughout the molding mass but not enough so that the shaped composite retains its shape when demolded, possibly after compaction. The water can come largely from the moisture in the residues taken from the fiberizing installation which uses large quantities of water, in particular to collect the residues. Water can also be introduced into the mixture to achieve both good mixing quality and good molding or compaction suitability.

[0097] Generally, water is present in the mixture at a rate of 2 to 30% by weight (preferably 4 to 15% by weight), based on the dry weight of the mixture.

[0098] The pH of the mixture is generally basic, typically at least 8 or even at least 10, or even at least 11.

[0099] Mineral wool recyclates contain the sizing (including phenolic resin) before being introduced into the mixture and coming into contact with the other ingredients of the mixture (apart from, where applicable, a little water already present on the mineral wool recyclates). The introduction of the mineral wool and the sizing including the phenolic resin into the mixture is therefore simultaneous, these ingredients being combined within the mineral wool recyclates before their introduction into the mixture.

[0100] The molding mass obtained by mixing is then transformed into a shaped composite, in particular into briquettes, by molding and possibly compaction. In particular, the molding mass can be placed in a mold, vibrated to remove trapped air, then possibly compacted by applying pressure to one of the moving faces of the mold.

[0101] The shaped composite then hardens naturally. It can dry out over time, so its water content can be significantly reduced over storage time. Its water content can vary depending on its storage conditions.

[0102] The shaped composite can, for example, have a volume greater than 1 cm 3 , for example greater than 20 cm 3 , in particular between 100 and 1000 cm 3 .

[0103] The present invention also relates to a shaped composite formed from a mixture comprising:

[0104] - at least 30% by weight of mineral wool recyclates comprising a sizing comprising a phenolic resin, - 11 to 25% by weight of hydraulic binder comprising clinker in a content of between 30 and 90% by weight,

[0105] - mineral fillers, and

[0106] - water.

[0107] More particularly, the present invention relates to a shaped composite obtainable by the method as defined in the present application.

[0108] Another object of the present invention is a method of manufacturing a mineral wool, comprising:

[0109] - a step a) of feeding a melting chamber, such as a cupola furnace, with a shaped composite as defined in the present application, as a vitrifiable charge, and

[0110] - a step b) of melting said shaped composite in said melting chamber, to obtain a bath of molten material, and

[0111] - a step c) of fiberizing said bath of molten material.

[0112] In one particular mode, the molten bath is immediately fiberized to obtain mineral wool. In another particular mode, the molten bath is cooled and transformed into cullet, which is subsequently (subsequently) melted again to be fiberized to obtain mineral wool.

[0113] The step of fiberizing the melt mixture can be carried out by internal or external centrifugation, preferably by external centrifugation.

[0114] For example, for external centrifugation, reference may be made to patent applications EP195725, EP 0465310 or EP 0439385, incorporated by reference. For internal centrifugation, reference may be made to patent applications EP 0189354 or EP 0519797, incorporated by reference.

[0115] It is understood that the various aspects, particular and preferred embodiments described above for the method of manufacturing the shaped composite also apply to the shaped composite according to the invention as well as to the method of manufacturing mineral wool which uses such a shaped composite. In the present application, a range defined with the expression "between (X) and (Y)" includes the lower (X) and upper (Y) limits, and is equivalent to "from (X) to (Y)".

[0116] The D50 indicates the value for which 50% of the particles - by mass - have a size less than or equal to this value, and 50% of the particles - by mass - have a size greater than this value.

[0117] D90 indicates the value for which 90% of the particles - by mass - have a size less than or equal to this value, and 10% of the particles - by mass - have a size greater than this value.

[0118] D50 and D90 are usually determined by laser granulometry.

[0119] The present invention also relates to a method of manufacturing a shaped composite, comprising: i') preparing a mixture comprising:

[0120] - at least 30% by weight (preferably at least 35% by weight, or even 40% to 60% by weight, or even 40% to 50% by weight) of mineral wool recyclates comprising a sizing comprising a phenolic resin,

[0121] - 3.3 to 22.5% by weight (preferably 4.7 to 18.0% by weight, or even 5.0 to 15.0%, or even 5.3 to 13% by weight) of clinker,

[0122] - 1.1 to 12.5% ​​by weight (preferably 1.5 to 10.0% by weight, or even 2.0 to 8.0%, or even 3.0 to 6.0% by weight) of one or more non-cementitious silica carriers (i.e. distinct from mineral wool),

[0123] - optionally, 0.11 to 6.25% by weight (preferably 1.5 to 10.0% by weight, or even 2.0 to 8.0%, or even 3.0 to 6.0% by weight) of one or more non-cementitious alkaline earth carriers (i.e. distinct from the mineral wool and distinct from the non-cementitious silica carrier),

[0124] - mineral fillers (preferably in a weight content of 5 to 60%, or even 30% to 60%, or even 40 to 55%), and

[0125] - water; and ii') the conformation of said mixture into a shaped composite, where the sum of the weight contents of clinker, non-cementitious silica carrier(s) and, if present, non-cementitious alkaline earth carrier(s) is at least 11% (for example, from 11 to 25%, preferably 11 to 20% by weight, or even from 11 to 15% by weight, or even from 12 to 14% by weight), the weight contents being expressed relative to the total dry weight of said mixture.

[0126] The mixture of step i') may also further comprise additive elements, generally in a weight content less than or equal to 1% by weight (relative to the total dry weight of said mixture).

[0127] The present invention also relates to a shaped composite formed from a mixture as defined above in step i').

[0128] It is understood that the various definitions (in particular the specific and preferred definitions) given above for mineral wool recyclates comprising a sizing comprising a phenolic resin, clinker, non-cementitious silica carriers, alkaline earth carriers, mineral fillers, and additives of the mixture of step i) also apply to those of the mixture of step i').

[0129] Furthermore, the implementation conditions (conditions for forming the mixture, conditions for forming the shaped composite, etc.) of steps i') and ii') are identical to steps i) and ii) respectively.

[0130] The following examples illustrate the invention in a non-limiting manner.

[0131] EXAMPLES

[0132] The ingredients listed in Table 1 are mixed in a mixer. The briquettes were formed by vibration molding, then compression, then demolding. The quantities indicated are percentages by weight of dry matter in the briquette, except of course for the "total water" column, which adds up all the water introduced into the mixture, in any way. The water content is expressed relative to the total dry weight of the mixture.

[0133] Cylindrical specimens measuring 11 cm (diameter) x 7 cm were formed. Compressive strength tests (measured in MPa) were carried out on these briquettes at 3 days and 21 days. The mineral wool recyclates contain 3% by weight of dry phenolic resin sizing residues (based on the total weight of dry mineral wool recyclates).

[0134] [Tables 1]

[0135] Table 1 shows that briquettes 1, 2, and 3, formed with a hydraulic binder having a clinker content of 46-76%, have good compressive strength at 3 days (>3 MPa) and at 21 days (>6 MPa). On the contrary, the comparative briquette with a lower binder content has a low compressive strength, less than 3 MPa at 3 days.

Claims

CLAIMS 1. A method of manufacturing a shaped composite, comprising: i) preparing a mixture comprising: - at least 30% by weight of mineral wool recyclates comprising a sizing comprising a phenolic resin, - 11 to 25% by weight of hydraulic binder comprising clinker in a content of between 30% and 90% by weight, - mineral fillers, and - water; and ii) conforming said mixture into a shaped composite.

2. Method according to claim 1, in which the hydraulic binder further comprises 10 to 50% by weight of one or more non-cementitious silica carriers distinct from the mineral wool.

3. The method of claim 2, wherein said non-cementitious silica carriers are selected from an alkali silicate, calcined or natural clay, kaolinite, illite, montmorillonite, calcined kaolin, dehydrated kaolin, silica fume, class C or F fly ash, biomass ash, blast furnace slag, steel mill slag, rice husk ash, rice husk, pozzolan, volcanic ash, diatomite, and a mixture of at least two of these.

4. Method according to any one of claims 1 to 3, in which the hydraulic binder comprises silica fume, preferably in a content of 5 to 15% by weight relative to the total dry weight of the hydraulic binder.

5. A method according to any one of claims 1 to 4, wherein the mineral wool recyclates comprise rock wool recyclates, glass wool recyclates, or a mixture thereof.

6. A method according to any one of claims 1 to 5, wherein the content of mineral wool recyclates is 40 to 60% by weight, relative to the total dry weight of the mixture.

7. Method according to any one of claims 1 to 6, in which the sizing is present in the mineral wool recyclates at a rate of 0.1 to 10% by weight, and more particularly at a rate of 0.5 to 7% by weight of dry sizing matter relative to the total weight of dry mineral wool recyclates.

8. A method according to any one of claims 1 to 7, wherein the phenolic resin is present in the size in an amount of 50 to 90% by weight of the dry matter of the size.

9. Process according to any one of claims 1 to 8, in which the weight content of mineral fillers is between 5% and 60% by weight, preferably between 30% and 60%, relative to the total dry weight of the mixture.

10. Method according to any one of claims 1 to 9, in which the mineral fillers are chosen from gravel, inert slag, and a mixture thereof.

11. Method according to any one of claims 1 to 10, in which the hydraulic binder represents from 11 to 20% by weight, preferably from 11 to 15% by weight, or even from 12 to 14% by weight, of the total dry weight of the mixture.

12. Method according to any one of claims 1 to 11, in which the hydraulic binder comprises clinker in a content of between 30% and 80% by weight.

13. Shaped composite obtainable by the method as defined in any one of claims 1 to 12.

14. Process for manufacturing mineral wool, comprising: - a step a) of supplying a melting chamber, such as a cupola furnace, with a shaped composite as defined in claim 13, as vitrifiable charge, and - a step b) of melting said shaped composite in said melting chamber, to obtain a bath of molten material, and - a step c) of fiberizing said bath of molten material.

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