METHOD FOR DETERMINING A FORMULATION FOR CONSTRUCTION BINDER

Abstract

The invention relates to a method (100) for determining a formulation for a construction binder, said construction binder comprising at least one by-product resulting from a lithium concentration process, said method being implemented by a computer device comprising a calculation module (16), said method comprising: - a step of receiving (130a), by the calculation module (16), a measured value of at least one physicochemical property of the at least one by-product resulting from a lithium concentration process; and - a step of selecting (150), by the calculation module (16), a quantity of the at least one by-product resulting from a lithium concentration process and a quantity of at least one complementary composition to form a construction binder; said at least one complementary composition being selected from: at least one precursor, a deflocculating polymer, an alkaline activation composition and a raw clay matrix.Figure to be published with the abstract: Figure 1.

Description

Title of the invention: METHOD FOR DETERMINING A FORMULATION FOR CONSTRUCTION BINDER Technical field

[0001] The invention relates to the field of construction materials and more particularly to the recovery of by-products from industry. In particular, the invention relates to a method for determining a formulation for a construction binder, a method for preparing a construction binder and a construction binder, a construction material and a suitable system. Prior art

[0002] Below we describe the known prior art from which the invention was developed.

[0003] The construction sector contributes significantly to global greenhouse gas emissions, accounting for approximately 37% of the total. This high percentage is largely due to the production and use of high-emitting materials such as cement, steel, and aluminum.

[0004] Thus, cement production is a major contributor to carbon emissions in the construction sector, mainly due to the energy-intensive nature of its production process and the chemical reactions involved in the manufacture of clinker, the main component of cement. The challenge is to reduce the carbon footprint of cement without compromising its performance or significantly increasing its costs. Some of the proposed strategies include improving the energy efficiency of transformation processes, using alternative fuels, and adopting new technologies for clinker production. However, a majority of studies focus on reducing the clinker content of cement by replacing it with additional cementitious materials such as fly ash, calcined clays, rice husk ash, or blast furnace slag.

[0005] The use of these additional cementitious materials such as fly ash, a by-product of coal combustion, and blast furnace slag, a by-product of steelmaking, in cement production offers a dual benefit: reducing the carbon footprint of cement and solving waste disposal problems. In particular, these materials can at least partially replace clinker in cement, thereby reducing the overall energy consumption and CO2 emissions associated with cement production.

[0006] However, for some of these additional cementitious materials, availability remains limited and for others, the footprint of the final construction material is not sufficiently reduced. Thus, the search for alternative components and precursors for low-carbon cement involves exploring new materials that can be used in the manufacture of low-carbon and circular cement.

[0007] It has recently been shown that the incorporation of lithium concentration by-products (e.g. Lithium Slag in English terminology) could confirm the potential of LS to serve as an additional cementitious material (Gou H et al., Cementitious and Geopolymer Composites with Lithium Slag Incorporation. Materials. 2024; 17(1):142. https: / / doi.org / 10.3390 / mal7010142). The use of these by-products could be part of a circular economy approach in which waste or lithium concentration by-products are used to reduce the use of materials with a high or moderate carbon footprint in construction such as clinker or metakaolins.

[0008] However, the use of these lithium concentration by-products in construction binders has produced cements with varying compressive strengths as well as drying shrinkage issues. Thus, there is a need for the development of composite mixtures with lithium concentration by-products that optimize compressive, flexural and tensile strengths as well as shrinkage. For this, a first step is to develop a method for determining optimized compositions for construction binders incorporating these lithium concentration by-products. Summary of the invention

[0009] The invention aims to overcome these drawbacks. The following presents a simplified summary of selected aspects, embodiments and examples of the present invention for the purpose of providing a basic understanding of the invention. However, this summary does not constitute an exhaustive overview of all aspects, embodiments and examples of the invention. Its sole purpose is to present selected aspects, embodiments and examples of the invention in a concise form as an introduction to the more detailed description of the aspects, embodiments and examples of the invention which follow the summary.

[0010] The invention relates in particular to a method for determining a formulation for a construction binder, said construction binder comprising at least one by-product resulting from a lithium concentration process, said method being implemented by a computer device comprising a calculation module, said method comprising:

[0011] - a step of receiving, by the calculation module, a measured value of at least a physicochemical property of at least one by-product from a lithium concentration process; and

[0012] - a step of selection, by the calculation module, of a quantity of the at least one by-product resulting from a lithium concentration process and an amount of at least one complementary composition to form a construction binder; said at least one complementary composition being selected from: at least one precursor, a deflocculating polymer, an alkaline activation composition and a raw clay matrix.

[0013] While the use of by-products of lithium concentration is in its infancy, the applicant has developed a process allowing the determination of a formulation for construction binder taking advantage of the characteristics of this by-product while supplementing its shortcomings with complementary compositions.

[0014] This makes it possible to generate a composition having mechanical characteristics adapted to the requirements of the construction sector.

[0015] According to other optional features of the method, the latter may optionally include one or more of the following features, alone or in combination: - at least one by-product from a lithium concentration process is from a process for preparing lithium hydroxide or lithium carbonate. - at least one by-product from a lithium concentration process has a D50 less than or equal to 20 pm. - at least one by-product from a lithium concentration process has a D90 less than or equal to 100 pm. - the by-product from a lithium concentration process is a composition comprising at least 35% SiO2. - the by-product from a lithium concentration process is a composition comprising at least 15% by weight of A12O3. - the by-product from a lithium concentration process is a composition comprising at least 20% by weight of CaCO3. Preferably, the at least one by-product from a lithium concentration process is a composition comprising at least 50% by weight of CaCO3. In particular, the CaCO3 is in the form of powder. - the at least one by-product resulting from a lithium concentration process is a composition comprising at most 2% by weight of lithium, preferably at most 1.75% by weight of lithium, more preferably at most 1.5% by weight of lithium and even more preferably at most 1.25% by weight of lithium. the at least one by-product from a lithium concentration process has a sulfur trioxide (SO3) content of less than or equal to 15% by weight, preferably less than or equal to 12% by weight, more preferably less than or equal to 10% by weight and even more preferably less than or equal to 8% by weight. This makes it possible to improve the stability of the construction material over the long term. the at least one by-product from a lithium concentration process has an amorphous phase content greater than or equal to 15%, preferably greater than or equal to 20%, more preferably greater than or equal to 25% and even more preferably greater than or equal to 30%. This improves the performance of the construction binder. the at least one by-product from a lithium concentration process is mixed with a deflocculating polymer, preferably the mixing between the at least one by-product from a lithium concentration process and the deflocculating polymer is carried out before mixing with any other complementary composition. This makes it possible to improve in particular the performance of the construction binder, in particular when the by-product from a lithium concentration process is added at a concentration greater than 20% by weight of the construction binder, preferably from a concentration greater than 30% by weight relative to the dry weight of the construction binder. the reference values ​​include correlations between measured values ​​of at least one physicochemical property of at least one by-product from a lithium concentration process on the one hand and quantities of complementary compositions adapted to said by-product from a lithium concentration process on the other hand. This mixture partially replaces the resources with a high or moderate carbon footprint usually used in construction binders (e.g. clinker, blast furnace slag, etc.). Comparison to reference values ​​corresponds to the use of a trained learning model. the selected quantities lead to a construction binder formulation having a lithium mass concentration of less than or equal to 1%, preferably less than or equal to 0.75%, more preferably less than or equal to 0.5%, and even more preferably less than or equal to 0.25%. the selected quantities lead to a construction binder formulation having a mass concentration of A12O3 greater than or equal to 5%, preferably greater than or equal to 7%, more preferably greater than or equal to 8%, and even more preferably greater than or equal to 9%. the selected quantities lead to a construction binder formulation having a mass concentration of A12O3 less than or equal to 15%, preferably less than or equal to 14%. the selected quantities lead to a construction binder formulation having a mass concentration of SiO2 greater than or equal to 20%, preferably greater than or equal to 25%, more preferably greater than or equal to 30%. the selected quantities lead to a construction binder formulation having a CaO mass concentration greater than or equal to 35%, preferably greater than or equal to 40%, more preferably greater than or equal to 42%. the selected quantities lead to a construction binder formulation having a CaO mass concentration of less than or equal to 60%, preferably greater than or equal to 57%, more preferably greater than or equal to 55%. the selected quantities lead to a construction binder formulation having a mass concentration of MgO less than or equal to 5%, preferably less than or equal to 4%, more preferably less than or equal to 3%. the selected quantities lead to a construction binder formulation having a mass concentration of Fe2O3 less than or equal to 5%, preferably less than or equal to 4%, more preferably less than or equal to 3%. the at least one complementary composition comprises at least one precursor selected from: slags such as blast furnace slags, steelworks slags, cupola slags; fly ash, natural pozzolans, silica fumes, micronized limestone fillers, micronized siliceous fillers such as glass powder, siliceous fillers, synthetic vaterite, diatomaceous earths, ground slags or combinations thereof; preferably selected from: blast furnace slags, micronized limestone filler; vaterite such as micrometric or nanometric vaterite; or combinations thereof. - the at least one complementary composition comprises at least one raw clay matrix relative to the dry weight of construction binder.

[0016] According to a second subject, the invention relates to a construction binder capable of being obtained by the process according to the invention, characterized in that it comprises at least one by-product resulting from a lithium concentration process, and at least one complementary composition, the at least one complementary composition being selected from a precursor, a deflocculating polymer, a raw clay matrix and / or an alkaline activation composition.

[0017] According to other optional characteristics of the binder, the latter may optionally include one or more of the following characteristics, alone or in combination: - It has a mass concentration of CaO less than or equal to 60% relative to the dry weight of construction binder. - it has a mass concentration of A12O3 greater than or equal to 5% relative to the dry weight of construction binder. - it has a mass concentration of MgO less than or equal to 5% relative to the dry weight of construction binder. - It comprises at least one raw clay matrix, preferably at least 10% by weight of raw clay matrix. Brief description of the drawings

[0018] Other characteristics and advantages of the invention will be better understood on reading the description which follows and with reference to the appended drawings, given for illustrative purposes and in no way limiting.

[0019] [Fig-1] [Fig.l] represents a method of determining a formulation for construction binder comprising at least one by-product from a lithium concentration process.

[0020] [Fig.2] [Fig.2] represents a method for preparing a construction binder according to the invention.

[0021] [Fig.3] [Fig.3] represents a method of preparing a construction material according to the invention.

[0022] [Fig.4] [Fig.4] represents a system for preparing a construction binder according to the invention.

[0023] The figures do not necessarily respect the scales, in particular in thickness, and this is for illustration purposes.

[0024] Aspects of the present invention are described with reference to flowcharts and / or functional diagrams of methods, apparatuses (systems) and computer program products according to embodiments of the invention.

[0025] In the figures, flowcharts and block diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams may represent a system, device, module, or code, which includes one or more executable instructions for implementing the specified logical function(s). In some implementations, the functions associated with the blocks may appear in a different order than shown in the figures. For example, two blocks shown in succession may, in fact, be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order, depending on the functionality involved.Each block of the block diagrams and / or flowchart, and combinations of blocks in the block diagrams and / or flowchart, may be implemented by special hardware systems that perform the specified functions or acts or carry out combinations of special hardware and computer instructions. Description of the embodiments

[0026] Below, we describe a summary of the invention and the associated vocabulary, before presenting the disadvantages of the prior art, and finally showing in more detail how the invention overcomes them.

[0027] In the remainder of the description, the term "binder" may be understood as a formulation making it possible to ensure the agglomeration of materials together, in particular during the setting and then hardening of a construction material. Thus, it makes it possible in particular to ensure the agglomeration of sand and other constituents of the construction material with the constituents of the binder. The binder according to the invention is in particular a hydraulic binder, that is to say that hardening takes place on contact with water.

[0028] The term "formulation" can be defined as the content values ​​of the different components of a composition.

[0029] The term "composition" may be defined as any entity composed of a single, quasi-pure compound or a mixture of several components. This entity may be in various physical forms, including but not limited to suspensions, solutions, or in the solid state including in powder form. The composition may be characterized by its specific formulation, including the proportions of its constituents, its physicochemical properties, and its manufacturing process. The expression "complementary composition" may be defined as corresponding to the entity or entities that combine with the by-product of a lithium concentration process to form a construction binder.

[0030] The term "by-product" within the meaning of the invention may correspond to a secondary product, composition or material which is produced or isolated during an industrial process such as, for example, the extraction, purification, transformation, production, concentration or destruction of a main product. It is generally not the main objective of the process and may have a characteristic or values ​​different from those of the main product.

[0031] The expression "by-product from a lithium concentration process" within the meaning of the invention therefore corresponds to a by-product obtained during the concentration and processing of lithium. The by-product of a lithium concentration process may have various physical and chemical characteristics associated with the numerous processes developed within the framework of the emerging lithium processing industry. It may correspond to a by-product obtained at any stage of a process aimed at obtaining more concentrated lithium.

[0032] For the purposes of the invention, a “deflocculating agent”, “deflocculant”, “deflocculating polymer” or “defloculation agent” may correspond to a compound capable of dissociating aggregates and colloids, particularly in aqueous suspension. Deflocculating agents have, for example, been used in the context of drilling or oil extraction to make clay more fluid and facilitate extraction or drilling.

[0033] The term "alkaline activation composition" means any composition having the function of accelerating the dispersion of an aluminosilicate source promoting the formation of stable hydrates with low solubility and the formation of a compact structure with these hydrates, thus increasing the mechanical resistance of the materials incorporating such an activation composition.

[0034] The expression "clay matrix", within the meaning of the invention, may correspond to one or more rock materials based on hydrated silicates or aluminosilicates with a lamellar structure, said clay matrix being composed of fine particles generally originating from the alteration of silicates with a three-dimensional framework, such as feldspars. A clay matrix may thus comprise a mixture of such rock materials which may, for example, consist of kaolinite, illite, smectite, bentonite, chlorite, vermiculite, or mixtures thereof. In addition, a clay matrix may comprise silts.

[0035] For the purposes of the invention, the expression “raw clay matrix” may correspond to a clay matrix that has not undergone a calcination step. For example, this corresponds to a clay matrix that has not undergone a temperature rise above 300°C, preferably above 200°C and more preferably a temperature above 150°C. Indeed, the raw clay matrix may undergo a drying step by heating requiring a temperature rise generally substantially equal to or less than 150°C but no calcination step. A raw clay matrix may preferably comprise a mixture of rock materials which may for example comprise kaolinite, illite, smectite, micas such as muscovite, bentonite, chlorite, vermiculite, or mixtures thereof, as well as silts.

[0036] The expression “physicochemical property”, in particular when it refers to a product, may correspond within the meaning of the invention to the properties which arise from both the physical state and the chemical composition of the product.

[0037] The expression “granulometric profile” within the meaning of the invention, can correspond to the distribution of the particles of a composition as a function of the relative weight importance of the different classes of particles identified by their size (eg diameter).

[0038] The expression "reference value" within the meaning of the invention may correspond to one or more predetermined values ​​making it possible, in combination with measured values, to determine complementary quantities and compositions suitable for the formation of a construction binder. The reference values ​​serve as a guide and may take, for example, the form of an algorithm, a learning model, limit values ​​or even charts.

[0039] The expression "% by weight" in relation to a composition, binder or construction material must be understood as being a proportion relative to the dry weight of the composition, binder or site concrete. The dry weight corresponds to the weight before the addition of water, for example, necessary for the formation of a construction material.

[0040] The expression "mixture made dry" within the meaning of the invention may correspond to the action of mixing one or more constituents without adding water or any other liquid. Advantageously, the hygrometry of a mixture made dry does not exceed 5% H2O and preferably 3% H2O, more preferably 2% H2O.

[0041] The expression “learning model” may correspond, within the meaning of the invention, in the context of artificial intelligence and machine learning, to a mathematical structure or an algorithm designed to learn patterns or behaviors from data measured or entered into a database.

[0042] Construction binder manufacturing processes generally have a high environmental footprint. Methods have been proposed to reduce this impact, including the use of lithium concentration by-products. However, significant variability can be observed in the performance of the construction binders generated.

[0043] Faced with this observation, the applicant has developed a new solution making it possible to determine a formulation for a low-carbon construction binder. Advantageously, the construction binder may have good mechanical properties such as that low shrinkage and high compressive strength at young age and at 28 days. As detailed below, the solution developed is based on the definition of a composition integrating at least one by-product from a lithium concentration process and complementary compounds, in suitable quantities to generate a binder meeting the requirements of the profession.

[0044] Thus, according to a first aspect and as illustrated in [Fig.l], the invention relates to a method 100 for determining a formulation for a construction binder comprising at least one by-product resulting from a lithium concentration process. Preferably, a method 100 for determining a formulation for a construction binder, said construction binder comprising at least one by-product resulting from a lithium concentration process according to the invention is implemented by a computer device comprising a calculation module 16.

[0045] As illustrated in [Fig.l], the method comprises: a step 130a of receiving a measured value of at least one physicochemical property of the at least one by-product resulting from a lithium concentration process; and a step 150 of selecting a suitable quantity of at least one complementary composition to be combined with the at least one by-product.

[0046] The at least one by-product from a lithium concentration process may correspond to any by-product generated during a lithium concentration process. In particular, the at least one by-product from a lithium concentration process is derived from a process for preparing high-purity lithium hydroxide or lithium carbonate. For example, a by-product in this process may correspond to lithium slag, lithium carbonates, sands and limestones or lithium silicates.

[0047] Generally, the by-product used in the context of the present invention will have a low lithium content. For example, a by-product used in the context of the present invention will have less than 5% by dry weight of lithium. It may have at most 2% by weight of lithium, preferably at most 1.75% by weight of lithium, more preferably at most 1.5% by weight of lithium and even more preferably at most 1.25% by weight of lithium.

[0048] The by-product from a lithium concentration process may correspond to a composition comprising at least 35% SiO2. The by-product from a lithium concentration process may correspond to a composition comprising at least 15% by weight of Al2O3.

[0049] Furthermore, the by-product from a lithium concentration process may correspond to a composition comprising at least 20% by weight of CaCO3, preferably at least 50% by weight of CaCO3.

[0050] Advantageously, the by-product generated during a (or resulting from a) lithium concentration process is used in solid form, for example in the form of a powder.

[0051] In particular, the at least one by-product resulting from a lithium concentration process has a D50 less than or equal to 50 pm, preferably less than or equal to 40 pm, and more preferably less than or equal to 20 pm. In addition, the at least one by-product resulting from a lithium concentration process has a D90 less than or equal to 200 pm, preferably a D90 less than or equal to 150 pm, and more preferably a D90 less than or equal to 100 pm.

[0052] As described, the present invention aims to combine a lithium concentration by-product with one or more complementary compositions to form a construction binder.

[0053] The at least one complementary composition may be selected from: at least one precursor, a deflocculating polymer, an alkaline activation composition and / or a raw clay matrix;

[0054] The at least one complementary composition may comprise a precursor.

[0055] The precursor may be selected from: slags such as blast furnace slags, steelworks slags, cupola slags; fly ash, natural pozzolans, silica fumes, micronized limestone fillers, micronized siliceous fillers such as glass powder, siliceous fillers, synthetic vaterite, diatomaceous earths, ground slag or combinations thereof.

[0056] Advantageously, the precursor may be selected from: blast furnace slag, micronized limestone filler; vaterite such as micrometric or nanometric vaterite; or combinations thereof.

[0057] In the invention, when the precursor is present, it may be present at a content of at least 1% by weight of the construction binder, preferably at a content of at least 10% by weight of the construction binder, even more preferably at a content of at least 15% by weight of the construction binder. Furthermore, preferably, the construction binder according to the invention comprises at most 25% by weight of precursor, more preferably at most 20% by weight of precursor.

[0058] Thus, in particular, a construction binder according to the invention may comprise between 1% and 25% by weight of precursor, preferably between 10% and 25% by weight of precursor, more preferably between 10% and 20% by weight of precursor.

[0059] Furthermore, the precursor according to the present invention may comprise a calcined clay. The calcined clay may be a raw clayey material which has previously undergone a heat treatment, preferably at a temperature of at least 450°C and at most 900°C, or in a “flash” calcination process at temperatures between 600°C and 900°C.

[0060] Preferably, the calcined clay material is dehydroxylated to an amorphous material while the formation of high temperature aluminosilicate crystalline phases such as mullite is prevented. The calcined clay matrix is ​​preferably amorphous, and has pozzolanic activity.

[0061] The calcined clay matrix can be formed with all the clay matrices mentioned in the present description. The calcined clay matrix can comprise, by way of non-limiting examples, at least one mineral species selected from: Metakaolin, Metaillite and / or Metamontmorillonite. Preferably, the clay matrix which has been calcined comprises kaolinite and / or illite. Thus, preferably, the calcined clay matrix corresponds to metakaolin or metaillite.

[0062] Preferably the calcined clay matrix is ​​a flashed clay matrix, such as for example metakaolin resulting from flash calcination.

[0063] The at least one complementary composition may comprise a raw clay matrix.

[0064] In the context of the invention, a raw clay matrix may for example comprise at least one mineral species selected from: Illite, Kaolinite, Smectite, Vermiculite, Chlorite, Montmorillonites, Muscovite, Halloysite, Sepiolite, and Palygorskite.

[0065] Preferably, the raw clay matrix may comprise at least two types of clays selected from: Illite, Kaolinite, Smectite, Vermiculite, Chlorite, Montmorillonites, Muscovite, Halloysite, Sepiolite, Interstratified, Pyrophyllite, talcs, Serpentines and Palygorskite. This includes so-called interstratified clays which are complex combinations of several clays. Even more preferably, the raw clay matrix may comprise at least one mineral species selected from: Kaolinite, Illite, Smectite, Palygorskite, Sepiolite, Chlorite, Montmorillonites, and Vermiculite.

[0066] Table 1 below presents the chemical characteristics of these mineral species. [Tables 1] Matrix A clayey C rue Type of clay Composition Illite (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,(H2O)] Smectite (Na,Ca)0.3(Al,Mg)2Si4O10(OH)2, n H2O Kaolinite Al2Si2O5(OH)4 Vermiculite (Mg,Ca)0.7(Mg,Fe,Al)6(Al,Si)8O22(OH)4nH2O Chlorite (Fe,Mg,Al)6(Si,Al)4O10(OH)8 Muscovite KAl2(AlSi3O10) (OH,F)2 Halloysite Al2Si2O5(OH)4 Sepiolite Mg4Si6O15(OH)2, n H2O Palygorskite (Mg,Al,Fe3+)5[Si8O20](OH)2 (OH2)4n H2O According to a preferred embodiment, a binder for construction material according to the invention may comprise at least two different types of clays and may comprise smectite (Smectite, Bentonite, Montmorillonite), kaolinite, and / or illite.

[0067]

[0068]

[0069]

[0070]

[0071] The type of clay can be determined by methods known to the person skilled in the art, for example after specific preparation of the samples using the so-called oriented blade method (see Thiry et al. - 2013 - Technique for preparing clay minerals for analysis by X-ray diffraction and introduction to the interpretation of diagrams). In particular, it will be possible to use X-ray diffractometry. For example, the following conditions may be used: - Equipment: Diffractometer, for example a BRUKER D8 ADVANCE (Bragg-Brentano geometry); for example with the following settings: Copper tube (X Kal ~ 1.54 Â) Generator power: 40 kV, 40 mA; Primary optics: fixed slit 0.16°; Soller slit 2.5°; Secondary optics: Soller slit 2.5°; LynXeye XE-T detector - Acquisition parameters: Scan from 4 to 90°20; Scan speed of 0.03°20 / second, Counting time: 480 seconds per step; Rotating sample. A construction binder according to the invention may comprise at least 5% by weight of raw clay matrix relative to the dry weight of construction binder, preferably at least 10% by weight of raw clay matrix, more preferably at least 15% by weight of raw clay matrix, even more preferably at least 20% by weight of raw clay matrix relative to the dry weight of construction binder. A construction binder may comprise at most 50% by weight of raw clay matrix relative to the dry weight of construction binder, preferably at most 40% by weight of raw clay matrix relative to the dry weight of construction binder, more preferably at most 30% by weight of raw clay matrix relative to the dry weight of construction binder, even more preferably at most 20% by weight of raw clay matrix relative to the dry weight of construction binder. A construction binder according to the invention may comprise from 5% to 50% by weight of raw clay matrix relative to the dry weight of construction binder, preferably from 5% to 40% by weight of raw clay matrix relative to the dry weight of binder. construction, preferably from 5% to 30% by weight of raw clay matrix relative to the dry weight of construction binder and even more preferably from 10% to 30% by weight of raw clay matrix relative to the dry weight of construction binder.

[0072] Advantageously, the raw clay matrix may have a D50 less than or equal to 200 pm, preferably less than or equal to 150 pm, more preferably less than or equal to 100 pm, even more preferably less than or equal to 80 pm.

[0073] The at least one complementary composition may comprise a deflocculating polymer. The presence of one or more deflocculating polymer(s) may improve the performance of the material formed from the construction binder. Many compounds may act as deflocculating polymers, many of which are generally known to those skilled in the art.

[0074] In the context of the invention, a construction binder may comprise an organic deflocculating agent, advantageously a deflocculating polymer. According to the present invention, an organic deflocculating polymer comprises at least one carbon atom and preferably at least one carbon-oxygen bond.

[0075] The deflocculating polymer may be a non-ionic surfactant such as a polyoxyethylene ether. The polyoxyethylene ether may for example be selected from: a poly(oxyethylene) lauryl ether. The deflocculating polymer may also be an anionic agent such as an anionic surfactant. In particular, the anionic agent may be selected from: alkylaryl sulfonates, amino alcohols, carbonates, silicates, fatty acids, humates (e.g. sodium humates), carboxylic acids, lignosulfonates (e.g. sodium lignosulfonates), polyacrylates, phosphates or polyphosphates such as sodium hexametaphosphate, sodium tripolyphosphate, sodium orthophosphate, carboxymethylcelluloses and mixtures thereof.

[0076] The deflocculating polymer may also be a polyacrylate. It may then be selected, for example, from sodium polyacrylate and ammonium polyacrylate.

[0077] The deflocculating polymer may also be an amine selected for example from: 2-amino-2-methyl-l-propanol; mono-, di or tri ethanolamine, isopropanolamines (l-Amino-2-propanol, diisopropanolamine, triisopropanolamine) and N-alkyl ethanolamines.

[0078] Preferably, the deflocculating polymer is selected from: a lignosulphonate (eg sodium lignosulphonate), a polyacrylate, a humate and their mixtures.

[0079] Preferably, the deflocculating polymer is selected from: a lignosulphonate (eg sodium lignosulphonate), a polyacrylate, a humate, a polycarboxylate such as an ether polycarboxylate, and mixtures thereof.

[0080] More preferably, the deflocculating polymer comprises a humate, a lignosulphonate and / or a polyacrylate.

[0081] Alternatively, the deflocculating polymer may be a mixture of compounds, such as a mixture comprising at least two compounds selected from: non-ionic surfactant, anionic agent, polyacrylate, amine and organophosphorus compound.

[0082] However, the invention cannot be limited to the deflocculating polymers mentioned above; any type of deflocculating polymer known to those skilled in the art can be used instead of said deflocculating polymers mentioned above.

[0083] The deflocculating polymer is preferably in the form of a salt. The deflocculating polymers that can be used according to the present invention may take a solid form or a liquid form.

[0084] In particular, the deflocculating agent, preferably the deflocculating polymer, represents at least 0.05% by weight of the construction binder, preferably at least 0.1% by weight of the construction binder, preferably at least 0.25% by weight of the construction binder, more preferably at least 0.5% by weight of the construction binder, more preferably at least 0.5% by weight of the construction binder, even more preferably at least 0.8% by weight of the construction binder and for example at least 1% by weight of the construction binder.

[0085] Furthermore, the deflocculating agent, preferably the deflocculating polymer, represents at most 5% by weight of the construction binder, preferably at most 4% by weight of the construction binder, more preferably at most 3% by weight of the construction binder and even more preferably at most 2% by weight of the construction binder. Indeed, too high a concentration is not necessary to form a material with advantageous mechanical properties.

[0086] In particular, the deflocculating agent, preferably the deflocculating polymer, represents between 0.05% and 5% by weight of the construction binder, preferably between 0.1% and 4% by weight of the construction binder, more preferably between 0.25% and 3% by weight of the construction binder, even more preferably between 0.5% and 2% by weight of the construction binder and even more preferably between 0.8% and 2% by weight of the construction binder and even more preferably between 0.9% and 2% by weight of the construction binder.

[0087] Advantageously, the deflocculating polymer is mixed beforehand with the by-product from a lithium concentration process. This makes it possible to improve in particular the performance of the construction binder, in particular when the by-product from a lithium concentration process is added at a concentration greater than 20% by weight of the construction binder, preferably from a concentration greater than 30% by weight relative to the dry weight of the construction binder.

[0088] The at least one complementary composition may comprise an alkaline activating composition.

[0089] Preferably, the alkaline activation composition may be selected from: clinker, CEM I, lime, silicates such as sodium silicate, carbonates such as sodium carbonate or combinations thereof. Advantageously, the activator comprises clinkers.

[0090] Furthermore, a construction binder according to the invention may comprise at least 5% by weight of alkaline activation composition relative to the dry weight of the construction binder, preferably at least 10%, more preferably at least 15%, and even more preferably at least 20% by weight of activator(s) relative to the dry weight of the construction binder.

[0091] A construction binder according to the invention may comprise at most 55% by weight of alkaline activation composition relative to the dry weight of the construction binder, preferably at most 50%, more preferably at most 45%, and even more preferably at most 40% by weight of activator(s) relative to the dry weight of the construction binder.

[0092] A construction binder according to the invention may comprise from 5% to 55% by weight of activator(s) relative to the dry weight of the construction binder, preferably from 10% to 50%, more preferably from 15% to 45%, and even more preferably from 20% to 40% by weight of activator(s) relative to the dry weight of the construction binder.

[0093] Preferably, the construction binder comprises at least 20% by weight of CEM I as activator relative to the dry weight of construction binder.

[0094] One of the features of the present invention is to combine a lithium concentration process by-product with complementary compositions to achieve target values ​​on certain constituents of the construction binder.

[0095] The step 150 of selecting a quantity of at least one by-product from a lithium extraction process and a quantity of at least one complementary composition is carried out by a calculation module configured for this.

[0096] The selection step 150 may advantageously comprise an analysis of input data (such as received data) to determine the optimal quantities of the constituents of a construction binder to achieve optimal final quantities. Furthermore, this may be based on optimal ratios between essential chemical elements based on predefined criteria reflecting the quantities and ratios expected to achieve desired performance characteristics of the binder.

[0097] Thus, advantageously, the selection step 150 makes it possible to obtain a formulation which, when implemented during the preparation of a construction binder, makes it possible to obtain defined performance characteristics. This particularly concerns mechanical performance such as mechanical strength and shrinkage. In particular, the selected quantities can determine the formulation of the construction binder and the method according to the invention can allow optimization of the formulation of an alkaline construction binder.

[0098] In particular, the calculation module will be able to establish comparisons between the measured value(s) of physicochemical properties with reference values. This comparison will be able to be carried out using predetermined charts or expert rules. The comparison is followed by a selection of suitable values ​​for the quantities of the different constituents making it possible to meet the predefined reference values.

[0099] Alternatively, this comparison may be carried out by a calculation algorithm configured to select the complementary compositions and the adapted quantities. This calculation algorithm may have been constructed from different learning models, in particular partitioning, supervised or unsupervised. An unsupervised statistical learning model may for example be selected from an unsupervised Gaussian mixture model, a hierarchical ascending classification (Hierarchical clustering Agglomerative in Anglo-Saxon terminology), a hierarchical descending classification (Hierarchical clustering divisive in Anglo-Saxon terminology). A supervised statistical learning model may for example be selected from kernel methods (e.g. Wide Margin Separators - Support Vector Machines SVM, Kernel Ridge Regression) described for example in Burges, 1998 (Data Mining and Knowledge Discovery.A Tutorial on Support Vector Machines for Pattern Recognition), ensemble methods (e.g. Bagging, Boosting, decision trees, Random Forest) described for example in Brieman, 2001 (Machine Learning. Random Forests), or neural networks described for example in Rosenblatt, 1958 (The perceptron: a probabilistic model for information storage and organization in the brain). Preferably, the previously calibrated computational algorithm has been obtained by implementing a statistical supervised learning method.

[0100] Advantageously, the method may comprise a step of creating a correlation between the measured values ​​received so as to calibrate a calculation algorithm. This correlation step, based on measured values, makes it possible to construct a calculation algorithm from a statistical learning model.

[0101] In particular, during the selection step, the complementary compositions and the quantities of by-product and complementary compositions are selected so that the construction binder has, in relation to its dry weight: - a mass concentration of lithium less than or equal to 1%, preferably less than or equal to 0.75%, more preferably less than or equal to 0.5%, and even more preferably less than or equal to 0.25%. - a mass concentration of A12O3 greater than or equal to 5%, preferably greater than or equal to 7%, more preferably greater than or equal to 8%, and even more preferably greater than or equal to 9%. - a mass concentration of A12O3 less than or equal to 15%, preferably less than or equal to 14%. - a mass concentration of SiO2 greater than or equal to 20%, preferably greater than or equal to 25%, more preferably greater than or equal to 30%. - a mass concentration of CaO greater than or equal to 35%, preferably greater than or equal to 40%, more preferably greater than or equal to 42%. - a mass concentration of CaO less than or equal to 60%, preferably greater than or equal to 57%, more preferably greater than or equal to 55%. - a mass concentration of MgO less than or equal to 5%, preferably less than or equal to 4%, more preferably less than or equal to 3%. - a mass concentration of Fe2O3 less than or equal to 5%, preferably less than or equal to 4%, more preferably less than or equal to 3%.

[0102] Furthermore, as illustrated in [Fig. 1], a method according to the invention may further comprise: a step 110 of providing the by-product resulting from a lithium concentration process; a step 120a of measuring at least one physicochemical property of the by-product resulting from a lithium concentration process; a step 120b of measuring at least one physicochemical property of at least one complementary composition; a step 130b of receiving at least one physicochemical value of at least one complementary composition; a step 140 of acquiring at least one reference value; a step 160 of selecting a quantity of additives to be added to the formulation for construction binder.

[0103] A determination method 100 according to the present invention may comprise a step of selecting a quantity of at least one additive to the construction binder formulation. The step 160 of selecting at least one additive makes it possible to complete the construction binder formulation.

[0104] The additives may, for example, correspond to molecules known to improve the performance of construction binders. An additive will generally be present at a mass concentration less than or equal to 10% relative to the weight dry weight of the construction binder. Preferably, the additive(s) will be present at a cumulative content of less than or equal to 8%, more preferably less than or equal to 7% and even more preferably less than or equal to 6%, for example less than or equal to 5%.

[0105] The additives may for example be selected from: amines (such as triethanolamine, triisopropanolamine, or hydroxyethyldiethylenetriamine), glycol-based compounds (such as monoethylene glycol, ethylene glycol, diethylene glycol, propylene glycol), phenolic compounds, glycerol, sodium stearate, sodium gluconate, or calcium nitrate.

[0106] According to another aspect, the invention relates to a construction binder.

[0107] In particular, the invention relates to a construction binder obtainable by the method for preparing a construction binder according to the invention. Preferably, the invention relates to a construction binder obtained by the method for preparing a construction binder according to the invention.

[0108] A construction binder according to the present invention will have the particularity of comprising at least one lithium concentration by-product. A construction binder according to the invention may also have the particularity of having been prepared by following the formulation selected within the framework of a selection method according to the present invention. Beyond this preparation characteristic, as described during the detailed description of the method for selecting the formulation for these advantageous embodiments, a construction binder according to the invention may have particular contents for certain chemical elements making it possible to achieve high performance despite the presence of a lithium concentration by-product.

[0109] The following characteristics are given for a binder in the dry state, preferably dehydrated. That is to say that it preferably has a water content of less than 5%, more preferably less than 3% and more preferably less than or equal to 2%.

[0110] Preferably, a construction binder according to the present invention has a CaO content of less than or equal to 60%. More preferably, a construction binder according to the present invention has a CaO content of less than or equal to 57%. Even more preferably, a construction binder according to the present invention has a CaO content of less than or equal to 55%. However, the applicant has also identified minimum CaO concentrations for obtaining construction binders with good properties. Thus, a construction binder according to the present invention has a CaO content of greater than or equal to 35%. More preferably, a construction binder according to the present invention has a CaO content of greater than or equal to 40%. Even more Preferably, a construction binder according to the present invention has a CaO content greater than or equal to 42%.

[0111] Preferably, a construction binder according to the present invention has an SiO2 content greater than or equal to 20%. More preferably, a construction binder according to the present invention has an SiO2 content greater than or equal to 25%. Even more preferably, a construction binder according to the present invention has an SiO2 content greater than or equal to 30%.

[0112] Preferably, a construction binder according to the present invention has a Li content (whatever the form) greater than or equal to 0.1%. More preferably, a construction binder according to the present invention has a Li content (whatever the form) greater than or equal to 0.2%. Even more preferably, a construction binder according to the present invention has a Li content (whatever the form) greater than or equal to 0.4%, for example 0.6% by weight relative to the dry weight of the construction binder.

[0113] Lithium can be present in the form of LiO, LiCO3, LiOH, LiClO4, LiSO4, Li3PO4, LiCl. The lithium concentration can be measured by ICP MS.

[0114] Preferably, a construction binder according to the present invention has an Al2O3 content of less than or equal to 15%. More preferably, a construction binder according to the present invention has an Al2O3 content of less than or equal to 14%. Preferably, a construction binder according to the present invention has an Al2O3 content of greater than or equal to 5%. More preferably, a construction binder according to the present invention has an Al2O3 content of greater than or equal to 7%. Even more preferably, a construction binder according to the present invention has an Al2O3 content of greater than or equal to 8%, for example greater than or equal to 9%. The Al2O3 concentration can be measured by X-ray fluorescence.

[0115] Preferably, a construction binder according to the present invention has a MgO content of less than or equal to 5%. More preferably, a construction binder according to the present invention has a preferred MgO content of less than or equal to 4%. Even more preferably, a construction binder according to the present invention has a preferred MgO content of less than or equal to 3%. The MgO concentration can be measured by X-ray fluorescence.

[0116] Preferably, a construction binder according to the present invention has an Fe2O3 content of less than or equal to 5%. More preferably, a construction binder according to the present invention has an Fe2O3 content of less than or equal to 4%. Even more preferably, a construction binder according to the present invention has an Fe2O3 content of less than or equal to 3%. The Fe2O3 concentration can be measured by X-ray fluorescence.

[0117] According to another aspect, the invention relates to a method for preparing a construction material obtained from a construction binder according to the invention.

[0118] As illustrated in [Fig.3], the method 300 for preparing a construction material may comprise a step 310a of providing a construction binder, and a step 310b of providing water, aggregates and / or fillers. In addition, the method will comprise a step 320 of mixing the construction binder with water, aggregates and / or fillers. The addition of water will conventionally be done at a content of between 0.4 and 0.6 of the dry weight of construction binder.

[0119] Thus, according to another aspect, the invention relates to a construction material obtained from a construction binder according to the invention.

[0120] A construction material according to the present invention may comprise aggregates. Conventionally, the aggregates may correspond to natural aggregates, artificial aggregates or even recycled aggregates.

[0121] The aggregates may also comprise mineral aggregates, i.e. mainly consisting of mineral matter and / or plant aggregates, i.e. mainly consisting of matter of plant origin. The aggregates may also comprise marine aggregates, i.e. mainly consisting of organic or inorganic matter from the seabed such as siliceous aggregates and / or calcareous substances (e.g. maerl and shell sands).

[0122] Mineral aggregates can, for example, correspond to sand, gravel, gravel, fillers (or fine materials), powders, fossilized waste and their combination.

[0123] Plant aggregates may, for example, correspond to wood (chips or fibers), hemp, straw, hemp shiv, miscanthus, sunflower, typha, corn, flax, rice husks, wheat husks, rapeseed, algae, bamboo, cellulose wadding, defibrated fabric and their combination.

[0124] In particular, when the construction material according to the invention comprises plant aggregates, said material preferably comprises at least 0.1% by weight of plant aggregates, preferably at least 0.2% by weight of plant aggregates, more preferably at least 0.5% by weight of plant aggregates, and even more preferably at least 0.7% by weight of plant aggregates.

[0125] According to another aspect, the invention relates to a system 1 for preparing a construction binder. A system 1 according to the present invention may be specially configured to obtain a construction binder from a method 200 for preparing a construction binder according to the present invention.

[0126] A system for preparing a construction binder according to the present invention may comprise a calculation module 16 as well as: a by-product tank 10, a complementary composition tank 11, a tank 12 for additives, a device for mixture 13, one or more transporter(s) 14, and / or one or more means 15 for detecting at least one physicochemical property.

[0127] In particular, a system 1 according to the present invention may comprise tanks 10, 11, 12 intended to contain the various constituents of the construction binder formulation. Thus, a system 1 may comprise at least one tank 10 intended to contain a by-product from a lithium concentration process. A system 1 according to the invention may also comprise at least one tank 11 intended to contain a complementary composition, advantageously the system 1 comprises at least one tank 11 per different compounds of the complementary composition, for example a tank 11 intended to contain at least one precursor, a tank 11 for the raw clay matrix, a tank 11 for the alkaline activation composition and / or a tank 11 for the deflocculating polymer. Advantageously the tanks 10, 11, 12 may be selected from: a tank, a container, a bin, a silo.

[0128] A system 1 according to the present invention may further comprise a mixing device 13. A mixing device 13 makes it possible to mix the different constituents of the construction binder formulation. A mixing device 13 may be selected from: a powder mixer; a belt mixer; a concentric ribbon mixer; a ploughshare mixer; a horizontal mixer. The mixer may be continuous or discontinuous.

[0129] A system 1 according to the present invention may comprise one or more conveyors 14. A conveyor 14 makes it possible, for example, to convey a quantity of at least one by-product resulting from a lithium concentration process, at least one complementary composition and / or at least one additive to the mixing device 13. Advantageously, each reservoir 10, 11, 12 is connected to the mixing device 13 by a conveyor 14 which is specific to it.

[0130] A conveyor 14 may be selected from flexible or non-flexible pipes, belts, conveyors or augers. Furthermore, in combination with the conveyor(s) 14, the system 1 may comprise pumps, valves, solenoid valves and flow limiters. In particular, the flow limiters may be arranged in functional switching with the conveyor(s) 14 to independently regulate the quantity of each of the ingredients distributed to the mixing device 13.

[0131] Furthermore, the system 1 according to the invention may comprise at least one measuring means 15 of at least one physicochemical property. Advantageously, the system 1 according to the invention comprises at least one measuring means 15 per reservoir 10, 11, 12. Thus, the at least one measuring means is capable of carrying out at least one measurement of at least one physicochemical property of the at least one by-product resulting from a method for concentrating lithium, at least one complementary composition and / or at least one additive. Such a measuring means 15 may for example be a pH meter, an X-ray diffractometer, a conductivity meter, an electron microscope, a mercury porosimeter, a spectrofluorometer, an ICP-MS, an HPLC-MS, a GC-MS, measurement of the specific surface area by the BET method, a granulometer, or even a rheometer.

[0132] A system 1 according to the invention may comprise a calculation module 16 capable of, preferably configured to, implement a computer program configured to carry out: - a step of receiving a measured value of at least one physicochemical property of a by-product resulting from a lithium concentration process, of at least one complementary composition and / or of at least one additive; - a step of selecting a quantity of at least one by-product from a lithium concentration process to form a construction binder and, - a step of selecting at least one complementary composition or at least one complementary composition and at least one additive, to form a construction binder on the basis of a comparison of the measured value(s) with reference values. Alternatively, a system 1 according to the invention may comprise a calculation module 16 capable of, preferably configured to, receive a formulation for construction binder comprising a quantity of by-product resulting from a lithium concentration process.

[0133] Furthermore, a calculation module 16 can control the conveyor(s) 14. For example, the calculation module 16 can control the conveyor(s) so that it / they convey a suitable quantity of the different constituents necessary for the formulation for construction binder according to the reference value(s). Also, a calculation module 16 can control the mixing device 13.

[0134] The invention may be the subject of numerous variants and applications other than those described above. In particular, unless otherwise indicated, the different structural and functional characteristics of each of the implementations described above should not be considered as combined and / or closely and / or inextricably linked to each other, but on the contrary as simple juxtapositions. Furthermore, the structural and / or functional characteristics of the different embodiments described above may be the subject in whole or in part of any different juxtaposition or any different combination.

Claims

Claims

1. Method (100) for determining a formulation for a construction binder, said construction binder comprising at least one by-product resulting from a lithium concentration process, said method being implemented by a computer device comprising a calculation module (16), said method comprising: - a step of receiving (130a), by the calculation module (16), a measured value of at least one physicochemical property of the at least one by-product resulting from a lithium concentration process; and - a step of selecting (150), by the calculation module (16), a quantity of the at least one by-product resulting from a lithium concentration process and a quantity of at least one complementary composition to form a construction binder; said at least one complementary composition being selected from: at least one precursor, a deflocculating polymer, an alkaline activation composition and a raw clay matrix.

2. Method (100) of determination according to claim 1, characterized in that the at least one by-product resulting from a lithium concentration process is resulting from a process for preparing lithium hydroxide or lithium carbonate.

3. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process has a D50 less than or equal to 20 pm.

4. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process has a D90 less than or equal to 100 pm.

5. Method (100) for determining a construction binder formulation according to any one of the preceding claims, characterized in that the by-product resulting from a lithium concentration process is a composition comprising at least 35% SiO2.

6. A method (100) for determining a construction binder formulation according to any preceding claim, characterized in that the by-product from a method lithium concentration is a composition comprising at least 15% by weight of A12O3.

7. Method (100) for determining a formulation for construction binder according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process is a composition comprising at most 2% by weight of lithium.

8. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process has a sulfur trioxide (SO3) content of less than or equal to 15% by weight.

9. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process comprises an amorphous phase content greater than or equal to 15%.

10. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one by-product resulting from a lithium concentration process is mixed with a deflocculating polymer, preferably the mixing between the at least one by-product resulting from a lithium concentration process and the deflocculating polymer is carried out before mixing with any other complementary composition.

11. Method (100) for determining a formulation for a construction binder according to claim 1, characterized in that it further comprises a step of acquiring (140) at least one reference value and in that the reference value(s) comprise correlations between measured values ​​of at least one physicochemical property of the at least one by-product resulting from a lithium concentration process on the one hand and quantities of complementary compositions adapted to said by-product resulting from a lithium concentration process on the other hand.

12. Method (100) of determination according to claim 11, characterized in that it further comprises comparisons between the measured value(s) of physicochemical properties with reference values ​​and in that the comparison with reference values ​​corresponds to the use of a trained learning model.

13. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of lithium less than or equal to 1%.

14. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of A12O3 greater than or equal to 5%.

15. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of A12O3 less than or equal to 15%.

16. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of SiO2 greater than or equal to 20%.

17. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of CaO greater than or equal to 35%.

18. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of CaO less than or equal to 60%

19. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of MgO less than or equal to 5%.

20. Method (100) of determination according to any one of the preceding claims, characterized in that the selected quantities lead to a construction binder formulation having a mass concentration of Fe2O3 less than or equal to 5%.

21. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one complementary composition comprises at least one precursor selected from: slags such as blast furnace slags, steelworks slags, cupola slags; fly ash, natural pozzolans, silica fumes, micronized limestone fillers, micronized siliceous fillers such as glass powder, siliceous fillers, synthetic vaterite, diatomaceous earths, ground slag or combinations thereof; preferably selected from: blast furnace slags, micronized limestone filler; vaterite such as micrometric or nanometric vaterite; or combinations thereof.

22. Method (100) of determination according to any one of the preceding claims, characterized in that the at least one complementary composition comprises at least one raw clay matrix.

23. A method (200) of preparing a construction binder, said method of preparing the construction binder comprising a step of mixing at least one by-product from a lithium concentration process and at least one complementary composition according to the construction binder composition of the selection method (100) according to claims 1 to 22.

24. Construction binder obtainable by the process for preparing a construction binder according to the preceding claim, characterized in that it comprises at least one by-product resulting from a lithium concentration process, and at least one complementary composition, the at least one complementary composition being selected from a precursor, a deflocculating polymer, a raw clay matrix and / or an alkaline activation composition.

25. Construction binder according to claim 24 characterized in that it comprises a mass concentration of CaO less than or equal to 60% relative to the dry weight of construction binder.

26. Construction binder according to any one of claims 24 or 25 characterized in that it comprises a mass concentration of A12O3 greater than or equal to 5% relative to the dry weight of construction binder.

27. ​​Construction binder according to any one of claims 24 to 26, characterized in that it comprises a mass concentration of MgO less than or equal to 5% relative to the dry weight of construction binder.

28. Construction binder according to any one of claims 24 to 27, characterized in that it comprises at least one raw clay matrix, preferably at least 10% by weight of raw clay matrix relative to the dry weight of construction binder.

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