Raw material composition, related utility products, and manufacturing methods

Abstract

The invention relates to a raw material composition (1), and a method (100) for manufacturing shaped products for building, manufacturing, and / or ornamental applications using said composition. In the method (100), the raw material composition (1) is prepared (102) by combining sand in an amount of 20 wt-% to 80 wt-% by dry weight, with at least feldspar, clay and nepheline, followed with admixing water thereto to form a homogenous mixture suitable for shaping (104); shaping (108) the homogenous mixture into a desired form to obtain an intermediate shaped product (10i); and thermally treating the intermediate shaped product (10i) to obtain a final shaped product (10). The invention further concerns the shaped product (10) obtainable by the method and uses thereof.

Description

[0001] RAW MATERIAL COMPOSITION, RELATED UTILITY PRODUCTS, AND MANUFACTURING METHODS FIELD OF THE INVENTION

[0002] The present invention pertains to raw material compositions formulated for the manufacture of various utility products, including building elements and ornamental items. Additionally, the invention relates to the associated products, the methods of manufacturing these products using the raw material compositions, and their applications.

[0003] BACKGROUND

[0004] The construction industry relies on a wide variety of materials to produce durable, functional, and visually attractive building elements. Among these, concrete has been one of the most widely used materials in construction for centuries owing to its durability, strength, and versatility. However, despite these advantages, building elements made of concrete encounter a number of major drawbacks that limit their performance, sustainability, and cost-effectiveness.

[0005] One of the most critical concerns with concrete is its significant environmental impact. The production of cement, a primary component of concrete, accounts for approximately 8% of total global carbon dioxide emissions, making it one of the largest industrial sources of greenhouse gas emissions. This is largely due to the energy-intensive processes of limestone (CaCCh) calcination to obtain lime (CaO) and carbon dioxide (CO2) followed with clinker production involving mixing of lime with an aluminosilicate mineral. Also production of concrete requires significant amounts of energy and water, which is challenging particularly in regions with limited water availability.

[0006] Cement-based materials, while offering adequate good compression strength, are naturally brittle, making them prone to cracking under stress. Even with incorporation of steel reinforcement elements, concrete structures frequently develop cracks due to shrinkage, thermal expansion, or external loads. These cracks create pathways for water and corrosive agents to infiltrate into the concrete structures, which leads to deterioration of embedded steel reinforcement through rusting. This degradation process reduces the lifespan of concrete structures and significantly increases maintenance costs. For constructions partially submerged in water, such as bridges, dams, and marine infrastructure, the problem is even more pronounced. Constantexposure to water and salts makes submerged structures particularly prone to corrosion and cracking, leading to more frequent maintenance and / or repairs, which significantly increase associated costs.

[0007] Furthermore, concrete is a dense and heavy material, which often presents logistical and practical challenges in construction. Transportation, handling, and installation of heavy concrete elements require specialized equipment, thus increasing project costs. Additionally, the heavy weight of concrete may act as a limiting factor in certain architectural an design projects, such as high-rise buildings or structures in seismically active areas, where the use of lightweight materials is often necessary. On the other hand, existing lightweight alternatives to traditional concrete, such as aerated or polystyrene-based concrete solutions, often lack the durability and strength required for load-bearing applications, leaving a significant gap in the materials market.

[0008] Another major problem is associated with the fact that not all sand is suitable for use in the production of concrete and other building materials due to variations in its physical and chemical characteristics. For example, desert sand, such as the naturally wind-formed sand prevalent in regions like the United Arab Emirates, was shown inadequate for construction purposes as having too smooth, rounded grains, which do not provide suitable bonding with cement and other aggregates. As a result, regions abundant in desert sand often rely on imported sand, sourced from elsewhere. This inevitably adds transportation costs to the construction projects.

[0009] Given the challenges outlined above, it is desirable to update the field of technology related to production of concrete-less building materials that address the shortcomings of traditional concrete while offering comparable or superior performance. Additionally, there remains a need to expand a range of sand types for use in a variety of applications in construction, decorative uses, and emerging manufacturing technologies.

[0010] SUMMARY OF THE INVENTION

[0011] An objective of the present invention is to solve or to at least mitigate at least some of the problems arising from the limitations and disadvantages of the related art. One or more objectives are achieved by various embodiments of a raw material composition, methods for manufacturing of building- and / or ornamental products using said raw material composition, related products and uses thereof. In one aspectof the invention, a raw material composition is provided, according to what is defined in the independent claim 1.

[0012] In an embodiment, a raw material composition comprises: (z) sand in an amount of 20 wt-% to 80 wt-% based on the total dry weight; and (zz) the remainder comprising feldspar, clay and nepheline.

[0013] In an embodiment, the composition comprises sand in an amount of 50 wt-% to 70 wt-% based on the total dry weight.

[0014] In an embodiment, in said composition, the sand comprises: natural sand, manufactured sand, or a mixture thereof.

[0015] In an embodiment, in said composition, the clay is composed of kaolin clay and / or ball clay.

[0016] In an embodiment, said composition further comprises an additional mineral or minerals selected from the group consisting of: bentonite, molochite, illite, gypsum, mica, and any combination thereof.

[0017] In an embodiment, the composition further comprises a dispersing agent and / or a pigment.

[0018] In another aspect, a method for manufacturing shaped products is provided, according to what is defined in the independent claim 7.

[0019] In an embodiment, said method comprises the steps of:

[0020] - preparing a raw material composition by combining sand in an amount of 20 wt-% to 80 wt-% by total dry weight, with at least feldspar, clay and nepheline, - forming a homogenous mixture suitable for shaping by admixing water into the raw material composition;

[0021] - shaping the homogenous mixture into a desired form to obtain an intermediate shaped product, and

[0022] - subjecting the intermediate shaped product to thermal treatment at a temperature within a range of 700 °C to 1300 °C to obtain a shaped product.

[0023] In an embodiment, in said method, the sand comprises any one of: natural sand, manufactured sand, or a mixture thereof. In an embodiment, the clay is composed of kaolin clay and / or ball clay.In an embodiment, in said method, water is admixed into the raw material composition in an amount of 5-40 wt-% based on the total wet weight of the composition.

[0024] In an embodiment, the method further comprises admixing a dispersing agent into the homogenous mixture. In an embodiment, the dispersing agent is added in an amount of 0.1-10 wt-% based on the total wet weight of the composition. In an embodiment, the dispersing agent is water glass.

[0025] In an embodiment, in said method, the shaping is implemented by a process selected from the group consisting of casting, molding, pressing extrusion, and any combination thereof.

[0026] In an embodiment, in said method, the shaping is implemented by a process of additive manufacturing (3D printing).

[0027] In an embodiment, in said method, the intermediate shaped product is subjected to surface finishing prior to being thermally treated.

[0028] In another aspect, a shaped product obtainable by the method outlined in another previous aspect and embodiments is provided, according to what is defined in the independent claim 17.

[0029] In embodiments, the shaped product is configured as a three-dimensional object selected from the group consisting of: a brick, a tile, a block, a slab, a paver, a panel, a rod, a filament, a pier, a girder, and any combination thereof.

[0030] In another aspect, use of the shaped product is provided according to what is defined in the independent claim 19.

[0031] In embodiments, the use of said shaped product is provided in an application selected from the group consisting of: (z) load-bearing structural applications, such as walls, columns, and foundations, (zz) flooring and roofing systems, (zzz) construction of infrastructure, such as bridges, tunnels and pavements, (zv) industrial linings, and (v) decorative and / or facade applications.

[0032] The utility of the present invention arises from a variety of reasons depending on the specific embodiment.

[0033] At the foremost, the cement-less raw material composition disclosed herein provides a sustainable and cost-effective alternative to traditional building concretes. By utilizing abundant and easily available materials such as sand and clays, thiscomposition reduces reliance on cement, a generally limestone-based material with a high environmental footprint, thus contributing to reduction of greenhouse gas emissions and other environmental impacts associated with cement production. The presented composition enable utilization of sand of any type, including naturally occurring sand or sand produced through mechanical processes. This includes wind-formed desert sands, sands sourced from riverbeds and seashores, as well as manufactured sand (M-sand), which is obtained by mechanically crushing rocks into fine particles.

[0034] When being combined with its wet component, the composition achieves a homogenous texture and consistency, making the resulting mixture suitable for various common shaping techniques. Additionally, the composition is easily adaptable for a wide range of industrial and decorative applications. These applications include, but are not limited to, - the construction and building industry, where the raw material composition can be used for manufacturing load-bearing structures, flooring, roofing systems, and other architectural components requiring high strength and durability; - the manufacturing sector, for fabricating components with enhanced mechanical properties and long-lasting performance; and - ornamental or decorative applications, such as tiles, panels, and decor elements.

[0035] Overall, the composition described herewith provides a versatile, cost-effective and sustainable alternative to traditional concrete compositions.

[0036] Within the present disclosure, the term “comprises” is intended to be construed as “includes, among other things”; whereas the term “consists of’ is intended to be construed as “consists of only”.

[0037] Within the present disclosure, the measurement error margin typically constitutes ±1.0-5.0 percent of the amount being measured, unless explicitly stated otherwise. Different embodiments of the present invention will become apparent by consideration of the detailed description and accompanying drawings.

[0038] BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Fig. 1 is a flow chart that outlines, at 100, a method for producing a shaped product 10, according to embodiments.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The present invention relates to a novel raw material composition, referred to herein as the “composition” and identified with a reference numeral 1 in FIG 1.

[0041] The composition generally comprises a sand fraction, which is composed of sand, and a non-sand fraction, which is composed of materials other than sand. The sand fraction of the composition is further referred to as “sand”. In an embodiment, the composition comprises sand in an amount of 20 weight-percent (wt-%) to 80 wt-% based on the total dry weight of the composition, and the remainder comprising feldspar, clay and nepheline. In an embodiment, the composition comprises sand in an amount of 50 wt-% to 70 wt-% based on the total dry weight of the composition. In certain embodiments, the composition comprises sand in an amount ranging from 20 to 80 weight-percent, based on the total dry weight of the composition, including specific values such as 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80 weight-percent, and any intermediate values within this range.

[0042] In embodiments, the sand fraction of the composition 1 comprises or consists of: (z) natural sand, (zz) manufactured sand (M-sand); or (zzz) a mixture of those.

[0043] In the present disclosure, the term “natural sand” or “naturally occurring sand” refers to sand composed of sand particles formed through natural processes, such as weathering, erosion, sedimentation, and similar mechanisms, and generally having a spherical or spheroidal shape. These particles are referred to as “natural sand particles”. The term “manufactured sand” refers to sand composed of sand particles produced through mechanical processes, such as crushing or grinding, and generally having an angular shape with sharp comers and edges.

[0044] In certain embodiments, the sand, represented by any one of natural sand, manufactured sand, or both has a particle size distribution ranging from 0.06 mm to 2 mm. Within this range, the sand can be further categorized into finer sand and coarser sand based on particle size.

[0045] The finer sand fraction, referred to here as fine sand, preferably exhibits a particle size distribution between 0.06 mm and 0.25 mm, while the coarser sand fraction, referred to here as medium-to-coarse sand, falls within a range of 0.25 mm to 2 mm. Additionally or alternatively, the invention allows for the use of sands with particle sizes smaller than 0.06 mm or larger than 2 mm. In certain cases, the composition 1can also include naturally occurring and / or manufactured sands containing fractions with particle sizes up to approximately 4-6 mm.

[0046] The particle size classification mentioned above generally aligns with that determined by standard sieve analysis using test sieves conforming to ISO 3310-1:2016 (Test sieves - Technical requirements and testing - Part 1: Test sieves of metal wire cloth). The particle size distribution generally aligns with that determined in accordance with EN ISO 17892-4:2016 (Geotechnical investigation and testing - Laboratory testing of soil - Part 4: Determination of particle size distribution), with sand types classified per ISO 14688-1:2018 (Geotechnical investigation and testing - Identification and classification of soil - Part 1: Identification and description).

[0047] For the purposes of this disclosure, references to the aforementioned standards include not only the versions valid at the time of this document's publication but also any subsequent updates, revisions, or equivalent standards that may supersede them. Thus, according to ISO 14688-1:2018, sand with particle sizes between 0.063 mm and 0.2 mm is classified as fine, sand with particle sizes between 0.2 mm and 0.63 mm is classified as medium, and sand with particle sizes between 0.63 mm and 2.00 mm as classified as coarse.

[0048] The natural and / or manufactured sand may thus consist of: a fine sand, a medium-to-coarse sand, or a mixture of these two. In such mixtures, the ratio of fine sand to medium-to-coarse sand may generally range from 1:99 to 99:1, expressed as a percentage of the total sand by weight. In one embodiment, the ratio of fine sand to medium-to-coarse sand may be provided as 50:50 by weight percent of the total sand. It is noted that the particle size classification within the present disclosure is intended merely as a reference to assist a skilled reader in approximating the dimensions of the natural and / or manufactured sand particles used in the composition 1 as disclosed herein.

[0049] In embodiments, the natural sand comprises or consists of a desert sand or dune sand. Desert sand is naturally abundant and characterized by its spheroidal shape and small particle size, typically below 0.25 mm (thus being classified as a fine sand). This type of wind-formed sand is smooth, rounded, and free-flowing, making it particularly suitable for applications requiring high homogeneity in the raw material mix. Desert sand may be sourced from regions with abundant dune formations, such as the Sahara Desert in North Africa, the dunes of Saudi Arabia and United Arab Emirates in the Middle East, and other geographical areas with similar natural deposits. Desert sandrepresents an abundant yet underutilized natural resource, therefore, its inclusion into the proposed raw material composition promotes sustainable material utilization. Desert sand or dune sand is primarily composed of silica (S i O2), predominantly in the form of quartz, which typically accounts for about 90% of its total dry weight. Depending on its geographic location and environmental conditions, it can also contain minor or trace amounts of other silicate minerals (e.g., feldspar, illite), gypsum (CaSO4-2H2O), various clay minerals (e.g., kaolinite, montmorillonite), carbonate minerals (e.g., calcite, dolomite), as well as iron oxides (e.g., Fe2O3), aluminium oxide (AI2O3), calcium oxide (CaO), oxides of alkali metals (e.g., K2O, Na2O), and heavy minerals (e.g., zircon, rutile, garnet).

[0050] Natural sand may also be represented with a coarser sand fraction (falling within a range of medium-to-coarse sands) or with mixtures of fine and medium-to-coarse sand fractions, obtainable from a variety of natural sources, including seashores, riverbanks, and excavations. The coarser sand fraction can also be sourced from natural deposits in quarries. This sand may be substantially pure, or it may contain impurities, such as silt and organic matter, as often included into sands excavated from river shores. In some instances, it is preferred that the sand is washed and / or screened.

[0051] For example, a so-called mason sand can be utilized, which is produced by crushing natural sand typically obtainable from quarries, riverbeds or seashores, followed with washing and screening to obtain uniform, clean sand having particle size distribution 0.063 mm and 2 mm.

[0052] It is noted that the impurities in the sand fraction of the composition are generally tolerable only within certain limits defined application- wise. In an event the sand fraction comprises major impurities like salts, chlorides, clays, and the like, pretreatment processes, such as washing and sieving, may be employed to reduce the level of impurities to acceptable thresholds to ensure consistent quality and performance.

[0053] The manufactured sand (M-sand) is produced by mechanically crushing and grinding rocks, such as granite, basalt, dolomite, sandstone, and the like. M-sand is characterized with angular or cubical shaped particles, whose size may range from medium-to-coarse sand particles down to fine powders (with particle sizes below 0.25 mm, such as for example 0.15 mm). Some commercially available manufactured sands exhibit particle size distributions, for example, from 0.1 mm to 0.6 mm; from 0.5 mm to 1.6 mm; or from 0.1 to 2 mm. In similar maimer, the manufactured sandcan be washed and / or screened before being used in preparation of the composition 1.

[0054] In terms of chemical composition, the silica content (primarily in the form of quartz) in sands other than desert sands is lower compared to that of desert sand or dune sand. For instance, sand excavated from riverbanks and seashores typically contains silica in the range of 50-80% of its total dry weight. Other components may include feldspar, mica, various impurities, and occasionally heavy minerals such as magnetite.

[0055] Manufactured sand has a chemical composition similar to that of the parent material (source rock). The primary component is typically silica in the form of quartz; however the rest of the composition varies depending on the source rock.

[0056] Within the concept of the present invention, any type of naturally occurring sand and / or sand produced by mechanical processes can be utilized.

[0057] In certain embodiments, the sand fraction is provided as a mixture of the natural sand and the manufactured sand. In said mixture, the ratio between the natural sand and the manufactured sand ranges between 1 : 99 to 99: 1 expressed as a percentage of the total sand by weight. In an embodiment, the ratio between the natural sand and the manufactured sand within the composition 1 is within a range of 50:50 to 99: 1 percent expressed as a percent weight fraction of the total sand.

[0058] The combination of natural sand and manufactured sand is particularly advantageous in manufacturing processes requiring optimal particle size gradation. The natural sand, mostly composed of fine, rounded particles, fills the voids between the angular grains of manufactured sand, enhancing the density and reducing porosity in the final product. This balance contributes to improved mechanical properties, such as compressive strength, and optimizes workability during shaping processes like casting, molding, or extrusion.

[0059] According to certain embodiments, the sand fraction of the raw material composition described herein consists of a blend of natural sand and manufactured sand, with their ratio ranging from 50:50 to 99:1, expressed as a percent weight fraction of the total sand fraction. A 50:50 ratio thus implies an equal proportion of natural sand and manufactured sand (i.e., each of the natural sand fraction and the manufactured sand fraction constitutes 50% of the weight of the total sand fraction), and the ratio 99:1 means that natural sand constitutes 99% of the weight of the total sand fraction. Overall, the fraction ratio of 50:50 ensures a balanced particle size distribution, whichis sufficient to achieve essential properties such as strength, workability, and compaction in the final product. The balanced particle size distribution arises from the complementary properties of the two sand types: natural sand typically has a smoother, rounded grain structure, while manufactured sand provides angular or cubical particles which enhance interlocking in construction application. This ratio can be further optimized based on specific application requirements and desired characteristics of the final product. For instance, fraction ratios in the range of 50:50 to 75:25 are particularly suitable for the construction of large structural elements, such as foundations for multi-floor buildings and bridges, where high strength and load-bearing capacity are critical.

[0060] In some embodiments, the sand fraction of the composition 1 consists of a natural sand (100% natural sand) or of a manufactured sand (100% manufactured sand). In some supplementary embodiments, the sand fraction of the composition 1 comprises or consists of one or more of the following: river sand, sea sand, desert sand, mason sand, washed sand, manufactured sand and / or any combination thereof.

[0061] The raw material composition 1 according to the present disclosure further comprises feldspar, clay, and nepheline. At least sand, feldspar, clay, and nepheline represent the dry components of the composition. It is preferred, that the ingredients representing the non-sand fraction of the composition are provided in the form of powder or fine grains having particle size not exceeding about 5 mm.

[0062] Feldspar is a group of aluminosilicate minerals that are primarily composed of alumina (AI2O3) and silica (S1O2) along with varying proportions of oxides of potassium, sodium, and calcium. Feldspars have the general chemical formula XAl(i 2)Si(3 2)08, where X is a variable cation (potassium, sodium, or calcium).

[0063] The invention advantageously utilizes different types of feldspar including, but not limited to: potassium feldspars, such as orthoclase (KAlSisOs), sodium feldspars, such as albite (NaAlSisOx), and calcium feldspar, such as anorthite (CaA12Si2O8). Among these, orthoclase (KAlSisOs) contains approximately 18.3% AI2O3, 64.7% SiO2, and 16.9% K2O; albite (NaAlSisOs) contains approximately 20.3% AI2O3, 67.4% SiO2, and 11.2% Na2O; and anorthite (CaA12Si2O8) contains approximately 35.8% AI2O3, 44.4% SiO2, and 19.2% CaO. Typical error margins for mineralogical compositions constitute ±0.1-0.5%.

[0064] In an embodiment, the clay is composed of kaolin clay and / or ball clay, the latter also referred to as plastic clay.Kaolin clay primarily consists of kaolinite, a hydrated aluminosilicate mineral with the general formula A12Si2Os(OH)4, and contains trace amounts of metal oxides, such as iron oxide (Fe20s) and titanium oxide (TiCh). Kaolinite is chemically composed of 46-50% silica (SiCh), 34-39% alumina (AI2O3), and 12-14% bound water. Processed kaolin is characterized by its fine grain size, with over 90% of particles smaller than 2 micrometers (pm). In contrast, raw kaolin clays typically have aggregated particles that can exceed 2 pm, reaching up to 10 pm, but these aggregates break down during processing, such as milling, resulting in finer particles.

[0065] Ball clay also contains kaolinite, but typically mixed with other minerals like mica, quartz, montmorillonite, and organic matter. Ball clays may thus contain 20-80% kaolinite, 10-25% mica (e.g. muscovite), 6-65% quartz and / or montmorillonite, and 1-4% of organic matter. It should be noted that the above-mentioned mineral components are not present in their maximum amounts simultaneously, as their proportions are typically interdependent and vary depending on the specific mineralogical composition of the ball clay deposit.

[0066] Kaolin clay and ball clay differ in their physical properties. Kaolin clay is non-plastic or has low plasticity, which limits its ability to be shaped. At the same time kaolin clay generally tolerates higher firing temperatures compared to ball clay (up to about 1600-1750°C). In contrast, ball clay is highly plastic and can be easily shaped or formed, but it has lower refractoriness (up to about 1200-1400 °C) due to impurities. Both kaolin clay and ball clay start to release bound water at approximately 250 °C and shrink during firing. However, ball clay exhibits greater shrinkage and begins to vitrify at a lower temperature (1200-1400°C) due to its higher impurity content and organic matter. This makes ball clay less refractory compared to pure kaolin clay. As a result, kaolin clay is preferred for products requiring low plasticity to minimize shrinkage during firing and to ensure stability at high temperatures. In contrast, ball clay is often chosen for applications where the clay must be worked into shapes without cracking.

[0067] In the raw material composition 1 disclosed herewith kaolin clay and ball clay are preferably used in combination. These clays complement each other in applications requiring both the strength associated with kaolin clay and the plasticity contributed by ball clay. The proportions of each clay type can be adjusted based on the specific requirements of the final product, such as its mechanical strength, thermal resistance, and appearance, as well as the intended area of application. In different embodiments, the composition 1 includes kaolin clay and ball clay in either equal proportions (50:50expressed as a percent weight fraction of the total clay fraction) or non-equal proportions, where the fraction of each of ball clay and kaolin clay may constitute 5-95% of the weight of the total clay fraction.

[0068] Dry raw material composition 1 further comprises nepheline. Nepheline (also called nephelite) is an aluminosilicate of sodium and potassium ([(Na,K)AlSiO4]). The composition of nepheline can vary depending on the specific geological environment in which it forms, but a typical nepheline composition includes at least silicon dioxide (SiCh), aluminium oxide (AI2O3) and notable amounts of sodium oxide (Na2O) and potassium oxide (IGO). In some non-limiting examples, the raw material composition 1 contained Nepheline N75 (nepheline syenite produced by Sibelco). Nepheline N75 has the following composition: SiO2: 55.4%, AI2O3: 24.6%, Na2O: 8.1%, IGO: 8.8%, CaO: 1.1%, MgO: <0.1%, TiO2: 0.07%, and Fe2O3: 0.1%, based on the total dry weight of the material. Nepheline obtainable from any other suitable source can be utilized.

[0069] The presence of nepheline in the raw material composition 1 lowers its melting point, allowing items made from it to be heat-treated at lower temperatures than those produced without nepheline. This can save energy and enable the use of ingredients that would otherwise not withstand high firing temperatures. In some instances, the presence of nepheline can lead to smoother, more uniform surfaces and hence contribute to the end-product quality.

[0070] In an embodiment, each of feldspar, kaolin clay, ball clay and nepheline are present in the raw material composition 1 in substantially equal proportions within the nonsand fraction of the composition. For example, in the composition comprising sand within 66-67% based on the total dry weight; each of the feldspar, kaolin clay, ball clay, and nepheline may be present in an amount of about 8.3% by total dry weight. Alternatively, the ingredients that constitute the fraction of raw material composition 1 excluding sand (i.e., feldspar, kaolin clay, ball clay, and nepheline), are present in non-equal proportions, with the amounts of each component varying relative to one another. The quantity of each non-sand ingredient in the composition may range from approximately 0.5 wt-% to 25 wt-%, based on the total dry weight of the composition. In one embodiment, the raw material composition 1 may further include one or more additional components or ingredients. These additional components may comprise, but are not limited to minerals, such as bentonite, molochite, illite, gypsum, and mica, which can be used individually or in any combination. Each of these additionalminerals is included in the composition 1 in an amount determined based on the specific requirements of the desired product and / or its intended application.

[0071] The composition comprises 20-80 wt-% of the non-sand fraction based on the total dry weight of the composition, and the amount of each of the above-mentioned additional components is adjusted on an individual basis within these limits. In some embodiments, the composition comprises 30-50 wt-% of the non-sand fraction based on the total dry weight of the composition.

[0072] The resulting raw material composition 1 is provided as a dry blend of the ingredients specified herein above. Dry composition may contain physically adsorbed water in an amount ranging from approximately 0.1 to 5.0 wt-% based on the total dry weight of the composition.

[0073] Amongst the above-mentioned additional components, bentonite (hydrous aluminosilicate mineral containing iron, magnesium, calcium, sodium and potassium) improves plasticity of a composition thus facilitating shaping and hence forming of shaped products. Bentonite contains both free and bound water and possesses a high water absorption capacity, which makes is useful for controlling moisture and enhancing the resistance of structures to water or humidity, particularly in waterproofing applications. Additionally, bentonite generally acts as a natural binder, improving cohesion of other raw materials during shaping and curing.

[0074] Molochite is a calcined form of kaolin clay produced by firing kaolin clay at high temperatures (approximately 1500 °C). As a result, molochite does not contain bound water and hence exhibits minimal thermal shrinkage. Compared to unprocessed kaolin clay, molochite possesses superior resistance to thermally-induced cracking and deformation. When incorporated into the raw material composition 1, molochite improves mechanical strength, abrasion resistance and chemical durability of the final product. It is particularly preferred in compositions intended for the fabrication of refractory ware, such as refractory bricks and tiles.

[0075] Illite is a mica-based, non-expanding clay mineral primarily composed of alumina, silica, and water, with minor to trace amounts of potassium, magnesium, and iron. It provides moderate plasticity, making to suitable for fabrication of products for applications ranging from building / construction to decoration. Additionally, illite enhances resistance to weathering and contributes to long-term durability of materials.Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate (CaSO4-2H2O). In addition to smoothness and lightweight properties, it also provides thermal insulation and soundproofing qualities to final products, which makes it essential in applications related to interior design (e.g., walls and ceilings). Gypsum is a key ingredient in plaster and plasterboard production.

[0076] In an embodiment, the composition 1 further comprises a dispersing agent. In an embodiment, the dispersing agent is water glass. Other dispersing agents include, but are not limited to for example DISPEX® (produced by BASF). In some configurations, the composition 1 additionally comprises pigments(s), preservatives, defoaming agents, and the like.

[0077] Reference is made to FIG. 1 illustrating, at 100, a concept underlying various embodiments of a method for manufacturing shaped products for a variety of applications, including, but not limited to building- and / or ornamental applications, using the raw material composition 1 as a starting material. The process phases that can be omitted in certain implementations of the method are indicated in dashed boxes.

[0078] The method 100 starts at 102 with preparing the raw material composition described herein above. The composition 1 is prepared by combining sand in an amount of 20 wt-% to 80 wt-% by dry weight, based on a total dry weight of the composition, with a non-sand fraction comprising at least feldspar, clay, and nepheline. In some embodiments, the sand fraction constitutes 50-70 wt-% (based on total dry weight). The clay component comprises or consists of kaolin clay, ball clay or a mixture thereof. In a latter case, the clay component can include kaolin clay and ball clay in equal or non-equal proportions. The non-sand fraction may further comprise any one of bentonite, molochite, illite, gypsum, mica, or any combination thereof.

[0079] The method continues at 104, by admixing water to the raw material composition 1 to form a homogenous mixture suitable for shaping. In an embodiment, water is added to the raw material composition 1 in an amount of 5 wt-% to 40 wt-% based on the total wet weight of the composition (i.e. of the total weight of the “wet” mixture obtained at step 104 and including both dry and wet (liquid) components). For the purposes of the present disclosure, the specified water content (5-40 wt-%) incorporates all liquid present in the homogenous mixture obtained at step 104, including both the initial moisture present in the dry blend (prepared at 102) and the added liquid (added at step 104).At 104, dry and liquid raw materials are combined and thoroughly mixed to ensure uniform distribution. Additionally, the dry materials may be (pre)mixed at step 102, prior to addition of the liquid component into the dry blend.

[0080] Additionally, pigments, preservatives, and other functional components may be added at this stage, as specified by the recipe.

[0081] In certain embodiments, the method 100 further comprises admixing (step 106) a dispersing agent into the homogenous mixture formed at step 104. In an embodiment, the dispersing agent is water glass. Water glass (also known as waterglass or liquid glass) is a mixture of sodium silicate compounds, such as sodium metasilicate (Na2SiOs), sodium orthosilicate (NaiSiCb) and sodium pyrosilicate (Na6Si2O?). These compounds share a similar structural basis but differ in the ratio of silicon dioxide (SiCh) to sodium oxide (Na2O). In some particular instances, a formulation of water glass could be composed entirely of a specific silicate, such as sodium metasilicate (Na2SiOs) or sodium orthosilicate (NaiSiCb).

[0082] In embodiments, the dispersing agent, such as for example, water glass is added in an amount of 0.1-10 wt-% based on the total wet weight of the composition.

[0083] The dispersing agent allows for improved fluidity and workability of the mixture to be shaped. In its common meaning, fluidity is defined as a capacity of the (fluid) material to flow, being opposite to viscosity (higher fluidity means lower viscosity, indicating that the mixture flows more easily). Workability is in turn defined as the relative ease with which the mixture can be handled and shaped.

[0084] For some applications, such as additive manufacturing (3D printing), addition of the dispersing agent, such as water glass, into the mixture to be shaped (the mixture prepared at step 104) is indispensable. Some 3D printing methods require up to 10 wt-% of water glass to be added into the feedstock mixture. For applications, other than 3D printing, addition of the dispersing agent is optional.

[0085] Thereafter the homogeneous mixture obtained in step 104 is shaped into a desired form (step 108) to produce an intermediate shaped product lOz. The shaping process can be carried out using a variety of techniques, including but not limited to casting, molding (e.g. injection-molding, pressing into molds, or any other suitable molding technique), pressing, extrusion, or any combination thereof. In some embodiments, the shaping step is implemented via a process of additive manufacturing (3D printing). Additive manufacturing methods include, but are not limited to, material extrusion-based techniques, such as fused filament fabrication (FFF), also known asfused deposition modeling (FDM), which utilizes a continuous thermoplastic filament for layer-by-layer construction, and Direct Ink Writing (DIW), a filament-or paste-based extrusion method suitable for ceramics for example. Any other suitable additive manufacturing methods, such as for example lamination-based techniques which involve stacking and bonding layers of material to build complex structures, can be utilized.

[0086] The selection of a specific shaping process employed by the method 100 may depend on various factors, including the composition of the mixture, the desired properties of the final product, and / or its intended application.

[0087] Once shaped, the intermediate product 10 / may undergo a drying process (step 110) to remove moisture and ensure dimensional stability, and / or a surface finishing process (step 112). Drying methods may include natural air drying, convection drying, tunnel drying, spray drying, or microwave drying, depending on the composition, size, and intended use of the product. Surface finishing procedures include, but are not limited to, polishing, coating, glazing, and / or painting for functional or decorative purposes, such as enhancing water resistance, reducing porosity, and improving appearance.

[0088] The method 100 further comprises subjecting the intermediate shaped product 10 / to thermal treatment (step 114), thereby a final shaped product 10 is obtained.

[0089] Thermal treatment is preferably conducted at temperatures within a range of 700 °C to 1300 °C. A temperature range of 1000 °C to 1300 °C was shown beneficial in some instances, with a temperature of about 1250 °C being optimal. The term “about” is defined in this context as a temperature value plus or minus 10 degrees Celsius (±10 °C). Thermal treatment can be conducted in any furnace, oven, or kiln conventionally used in the production of pottery, tiles, and industrial ceramics.

[0090] In embodiments, thermal treatment 114 is conducted for a period of 3-10 hours at atmospheric pressure. In embodiments, the duration of thermal treatment is 4-5 hours. The duration and temperature regime of the thermal treatment can be adjusted within this range on a case-by-case basis, based on factors such as the desired material properties and the composition of the raw materials. Additionally, the size of the shaped items (i.e. intermediate shaped products 10 / ) and / or the batch size (representing the quantity of items to be processed in a single furnace batch) also affect the duration and / or temperature regime of the thermal treatment.A shaped product 10 is defined herewith as is a three-dimensional object with a defined form that is created by subjecting a homogeneous mixture of raw materials to one or more shaping processes 108 and subjected to thermal treatment 114. Production of the shaped product 10 may further involve drying (step 110) and surface finishing (step 112). The shaped product 10 is a final product to be used in applications related to construction, fabrication of industrial components, decoration, and other related fields, as discussed further below. The 3D shape of the shaped product 10 is not restricted as long as it is usable in a variety of building and / or ornamental applications as defined in present disclosure. The shaped product 10 can be provided as a self-contained, standalone item or as a part or component of a more complex structure.

[0091] The shaped product 10 exhibits a compressive strength ranging from 30 to 100 MPa. In certain embodiments, it achieves specific compressive strengths of 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100 MPa, including any intermediate values within this spectrum. In certain realizations, the shaped product 10 demonstrates a compressive strength of at least 85 MPa. Procedures for determining compressive strength generally comply with at least the European standards EN 12390-3 and EN 12504-1, as adopted in Finland. Specifically, EN 12390-3:2019 pertains to the determination of compressive strength of test specimens made from hardened concrete, while EN 12504-1:2019 addresses the determination of compressive strength using cores extracted from hardened concrete.

[0092] This high level of compressive strength ensures the thermally treated product's suitability for use as a building and / or ornamental element in demanding applications where durability and structural integrity are essential.

[0093] In embodiments, the shaped product 10 is configured as a three-dimensional object configured as any one of: a brick, a tile, a block, a slab, a paver, a panel, a rod, a filament, a pier, a girder, or any combination thereof.

[0094] The shaped products 10 are versatile and may be employed in a variety of structural, functional and decorative applications. Specifically, the invention relates to the use of a shaped product 10 in a variety of applications including, but not limited to:

[0095] (i) Load-bearing structural applications: The shaped product 10 can be used in walls, columns, foundations, and other structural components that require high compressive strength and stability. With compressive strengths equal to orexceeding 85 MPa, these shaped products can support both static and dynamic loads in commercial, residential and industrial construction environments.

[0096] (ii) Flooring and roofing systems: The shaped product 10 is suitable for use in flooring tiles, roof tiles and structural panels, where durability, resistance to wear and attractive appearance are important.

[0097] (Hi) Infrastructure construction: The shaped product 10 can be used as a structural component and / or reinforcing element in infrastructure projects, including bridges, tunnels and pavements. For instance, in bridge construction, these products can be integrated into supporting frameworks, roadbeds or as cladding to enhance structural performance and resistance to environmental conditions. In tunnels and pavements, these products can be utilized for lining and / or reinforcement.

[0098] (iv) Industrial linings: The shaped products 10 can be utilized as refractory linings or protective layers in industrial environments which involve high-temperatures. These products may include heat-resistant bricks, tiles, or other components used for lining furnaces, kilns, or reactors in high-temperature production processes, such as glassmaking, steel production, and similar applications.

[0099] (v) Decorative and facade applications: The shaped product 10 can be used in custom designs for architectural elements, including facade panels for buildings, ornamental cladding and / or decorative features for interior design and / or gardens. Specific manufacturing methods allow for smooth, textured, or glazed finishes, catering to both functional and decorative requirements in modem architecture. Table 1 presents an overview of the most suitable shaping methods for forming composition 1 into three-dimensional products 10, optimized for the exemplary applications listed above. This table is not exhaustive, but aims to provide a skilled reader with a general overview of the possibilities enabled by the invention.

[0100] Table 1. Applications and corresponding shaping methods

[0101]

[0102]

[0103] As can be observed from Table 1, 3D printing can be applied across all the applications described above. On the other hand, the production of complex components, such as those used in architecture, may require a combination of the above-mentioned techniques. For example, molding, extrusion, and pressing can be combined to achieve multifunctional designs and to meet specific requirements related to size, shape, and performance.

[0104] Experimental Examples

[0105] Example 1: Composition Preparation

[0106] A raw material composition 1 was prepared with the following proportions:

[0107] Sand: 66,8 wt-% (50% natural sand, 50% manufactured sand).

[0108] Feldspar: 8,3 wt-%.

[0109] Kaolin clay: 8,3 wt-%.

[0110] Ball clay: 8,3 wt-%.

[0111] Nepheline: 8,3 wt-%.

[0112] Example 2A: Shaped Product Manufacturing

[0113] The dry composition obtained in Example 1 was combined with 10 wt-% water, shaped via pressing, and fired at 1250 °C for 4 hours. The resulting product had a compressive strength of 85.5 mPa. The compressive strength was measured for asquare slab with dimensions of l0 x l0 x 5 (length x width x height) and having a compressed area of 8075.0 mm2using a conventional compressive strength testing machine, such as the one from Toni Technik, during a test run. Duration of the test was 2 min 20 sec; the test speed was 0.58 MPa / s, and the maximum load was 690.3 kN.

[0114] Example 2B: Shaped Product Manufacturing

[0115] The dry composition obtained in Example 1 was combined with 40 wt-% water and 10 wt-% water glass, shaped via 3D printing (FFF method), and thermally treated at 1250 °C for 4 hours.

[0116] It is clear to a person skilled in the art that with the advancement of technology the basic ideas of the present invention may be implemented in various ways. The invention and its embodiments may generally vary within the scope of the appended claims.

Claims

Claims1. A raw material composition (1) for use in production of building- and / or ornamental elements, comprising:- sand in an amount of 20 wt-% to 80 wt-% based on the total dry weight;and- the remainder comprising feldspar, clay and nepheline.

2. The raw material composition (1) of claim 1, comprising sand in an amount of 50 wt-% to 70 wt-%.

3. The raw material composition (1) of claim 1, wherein the sand comprises:natural sand, manufactured sand, or a mixture thereof.

4. The raw material composition (1) of claim 1, wherein the clay is composed of kaolin clay and / or ball clay.

5. The raw material composition (1) of any preceding claim, further comprising an additional mineral, said additional mineral being selected from the group consisting of: bentonite, molochite, illite, gypsum, mica, and any combination thereof.

6. The raw material composition (1) of any preceding claim, further comprising a dispersing agent and / or a pigment.

7. A method (100) for manufacturing shaped products for building- and / or ornamental applications, comprising the steps of:- preparing (102) a raw material composition (1) by combining sand in an amount of 20 wt-% to 80 wt-% by dry weight, with at least feldspar, clay and nepheline,- forming (104) a homogenous mixture suitable for shaping by admixing water into the raw material composition (1);- shaping (108) the homogenous mixture into a desired form to obtain an intermediate shaped product (lOz), and- subjecting the intermediate shaped product (lOz) to thermal treatment (114) at a temperature within a range of 700 °C to 1300 °C to obtain a shaped product (10).

8. The method (100) of claim 7, wherein the sand comprises any one of: natural sand, manufactured sand, or a mixture thereof.

9. The method (100) of claim 7, wherein the clay is composed of kaolin clay and / or ball clay10. The method (100) of claim 7, wherein water is admixed into the raw material composition (1) at step (104) in an amount of 5-40 wt-% based on the total wet weight of the composition.

11. The method (100) of any preceding claim 7-10, further comprising admixing (106) a dispersing agent into the homogenous mixture formed at step (104).

12. The method (100) of claim 11, wherein the dispersing agent is added in an amount of 0.1-10 wt-% based on the total wet weight of the composition.

13. The method (100) of any one of claims 11 or 12, wherein the dispersing agent is water glass.

14. The method (100) of claim 7, wherein the shaping (108) is implemented by a process selected from the group consisting of casting, molding, pressing extrusion, and any combination thereof.

15. The method (100) of claim 7, wherein the shaping (108) is implemented by a process of additive manufacturing (3D printing).

16. The method (100) of any preceding claim 7-15, wherein the intermediate shaped product (lOz) is subjected to surface finishing (112) prior to being thermally treated.

17. A shaped product (10) configured as a three-dimensional object obtainable by the method according to any one of claims 7 to 16.

18. The shaped product of claim 17, configured as a three-dimensional object selected from the group consisting of: a brick, a tile, a block, a slab, a paver, a panel, a rod, a filament, a pier, a girder, and any combination thereof.

19. Use of the shaped product (10) as defined in any one of claims 17 or 18 in an application selected from the group consisting of: (z) load-bearing structural applications, such as walls, columns, and foundations, (zz) flooring and roofing systems, (zzz) construction of infrastructure, such as bridges, tunnels and pavements, (zv) industrial linings, and (v) decorative and / or facade applications.

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