A shaped article comprising mineral wool, a method for producing the shaped article, and a production line for carrying out the method of producing the shaped article

Abstract

The subject of the invention is a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that it comprises, in dry matter, up to 40% w / w of all alkaline compounds originating from the mineral wool and from an addition of a metal hydroxide or metal hydroxides, which constitute the sole binder of the shaped article. The invention also provides a method for producing the shaped article and a production line for implementing said method.

Description

[0001] A shaped article comprising mineral wool, a method for producing the shaped article, and a production line for carrying out the method of producing the shaped article

[0002] Field of the invention

[0003] The subject of the invention is a shaped article comprising mineral wool, for example recycled mineral wool, and in particular industrial waste mineral wool, a method for producing such a shaped article, and a production line for carrying out the method for producing said shaped article.

[0004] The term shaped article is to be understood broadly as a prefabricated element which has been given a predetermined shape in an industrial process. The shaped article may take a form selected from the group comprising any type of shaped body, e.g., cuboidal, cylindrical, spherical, and others, having the form of a briquette or a finished aggregate, for instance, in the form of a granulate, flakes, scraps, particles, lumps, blocks, plates, columns, etc. The shaped article may have a repeatable spatial form (each with identical dimensions, which is typical for briquettes) or may consist of a mixture of various shaped bodies of different shapes and sizes; for example, a granulate may be composed of granules of various sizes. Granulates and other forms of smaller size and irregular shapes than a briquette replace an aggregate (constituting a formed, finished aggregate).

[0005] The term “waste mineral wool” is to be understood as referring to any waste and residues arising from the processes of producing mineral wool, including the manufacturing of its fibers. Mineral wool from recycling is a broader concept and pertains not only to industrial waste but also, for example, to construction and demolition waste obtained from the dismantling of buildings, etc. The invention is particularly dedicated to the reprocessing of waste mineral wool, but it can also be recycled wool, i.e., from municipal selective waste collection systems.

[0006] Rock wool is a mineral fiber used mainly in construction as thermal insulation or as a fire protection element. It is obtained by melting a natural raw material at a temperature of about 1600°C in a melting furnace, usually in a shaft furnace. The molten material is then subjected to centrifugal force to produce fibers, which constitute the final product. In many industrial processes for obtaining mineral wool, a mineral raw material feedstock is used in the form of briquettes (shaped bodies) or granulates, rather than natural materials. Such a solution is primarily used when strict limitations on the composition of the final product are imposed.

[0007] Currently, waste, surplus, or rejects of mineral wool and residual materials from other industries are pressed into briquettes (prefabricated elements), which are then introduced into a shaft furnace to be re-formed into mineral wool. The use of natural mineral materials is not always satisfactory because their chemical composition is varied, and even the slightest deviations in the chemical composition of the raw material can affect the quality of the final product - the mineral wool. By replacing natural materials with prefabricated briquettes, it is possible to control the chemical composition of the raw material and, consequently, the quality of the final product.

[0008] The term “strongly alkaline waste” is to be understood as referring to all waste streams, residues from crude oil refining processes, petrochemical processes, and any other chemical processes that involve the use and generation of by-products or waste products of a basic nature. The invention covers the use as a binder in shaped articles of waste with a strongly alkaline character, but it can also be used for processing all types of post-reaction waste from chemical processes that exhibit an alkaline character (the pH of post-process waste is in the range of 8-14) - hydroxides, oxides, salts, complex compounds, inorganic and organic compounds.

[0009] Currently, there are several methods for the treatment or disposal of industrial alkaline waste, but none of them are without drawbacks. Alkaline products that are not so contaminated as to prevent their reuse in chemical processes are most often concentrated by evaporating the solvent and recycled back into the process. This method often involves a huge energy input to evaporate the solvent. It is only used for non-contaminated and sufficiently concentrated alkaline waste, so that the costs of the concentration process do not exceed the costs of using new alkaline material. Other methods of processing alkaline waste involve further dilution with water and disposal through gradual release into the environment. This method is very time-consuming and does not allow for the disposal of waste produced on a large scale without significant interference with the natural environment. Furthermore, a necessary requirement is the prior treatment of such waste by processes such as oxidation or reduction, to eliminate any potential pollutants hazardous to the natural environment (especially organic compounds). Another way of processing alkaline waste is to subject it to reaction with acids to form salt compounds (so-called neutralization), which could then be released into the environment. However, this method, much like dilution, requires the use of multistage treatment methods to eliminate toxic, hazardous compounds and vast amounts of water, so that the salt compounds can also be released into the environment after appropriate dilution. All the aforementioned methods for treating industrial alkaline waste are often uneconomical and pose a threat to the natural environment if their treatment is insufficient or improper. Moreover, the mentioned methods for the disposal of alkaline waste products do not allow for their possible application in the same or other industries, but only transform them into substances that are relatively neutral to the environment. The effect of this is the need to re-acquire fresh alkalis for one-time use in industrial processes, which generates further economic losses and negatively impacts the natural environment, instead of reusing them, bypassing direct disposal.

[0010] A reason for using pre-processed (solidified with a binder) briquettes or granulates instead of raw natural materials is the ability to optimize the particle size of the feedstock. The particle size of the raw material, which is the feed material in furnaces, is a key aspect in the material melting process in the furnace.

[0011] The most commonly used furnaces are the traditional shaft furnace, the gas-fired shaft furnace, and the electric furnace. In different types of furnaces, the thermal energy that liquefies the mineral raw material is generated through different processes. In a traditional shaft furnace, the mineral raw material is charged together with fuel, usually coke, which upon combustion generates the energy necessary to liquefy the raw material. In a gas-fired shaft furnace, heat is introduced by burning gas or another liquid fuel, and in an electric furnace, electrodes are used which extend into the furnace interior and generate the energy required to melt the mineral material filling the furnace.

[0012] When using a shaft furnace to melt the raw material, it is only permissible to use a relatively coarse feed material, as this fine material tends to form a compact mass in the furnace during melting. As a result, the flow of air and flue gases through the furnace charge is hindered. Moreover, finely ground material is more difficult to handle, including in charging the feed into the furnace. Using finely ground raw material also produces a large amount of dust, which is a major problem in processes requiring the use of electric furnaces. Therefore, it is not possible to fully utilize the raw material originating from all possible sources, including waste material from mineral fiber waste or non-fibrous material, the so-called sinters formed during mineral wool production. The effect of this is, of course, an economic loss, but also a reduction in the available sources of mineral raw material.

[0013] Transforming mineral wool waste into shapes other than briquettes, for example, in the form of granulates (formed aggregates), not only allows for the disposal of this product but also, after appropriate processing - forming and drying in proper devices creating a production line - allows for avoiding the problems of processing small shapes, the presence of fines or dust. However, most importantly, the production of granulates / aggregates by the presented method allows for a reduction in the use of natural aggregates, and perhaps even the cessation of exploiting the natural environment for their acquisition or production. Furthermore, the process of producing smaller shaped bodies (granules) is shorter, as the curing or drying processes are shorter, e.g., from 3-4 hours for briquettes, they are shortened to 10 to 30 minutes for granulate.

[0014] State of the art

[0015] Attempts have been made to solve the problem of using fine mineral raw material by forming smaller mineral raw materials into briquettes. However, this involved the use of an additional material - a binder for the mineral raw material. For this purpose, hydraulic binders were used, primarily Portland cement, clay, and water glass. The use of Portland cement makes the briquette have poor resistance to high temperatures, it loses its strength and becomes brittle at relatively low temperatures (400 - 500°C), causing the material to disintegrate and pose the same problem as an unbound, fine raw material. The use of cement as a binder also brings a number of other negative effects, e.g., emissions of sulfur and carbon oxides, or the formation of deposits clogging the outlet of the shaft furnace.

[0016] The use of a binder for briquettes made of slag activated by an alkaline agent is known. Such slag has a glassy structure and is in the form of a granulate, which is easily activated by an alkaline agent. Mineral raw material briquettes produced according to this method show good strength properties, especially in relation to moisture, and good properties in the melting process itself. Currently, the only utilized method of recycling mineral wool waste is its briquetting and subsequent return to the production process of re-producing full-value mineral wool. The generated post-production waste from mineral wool cannot be returned directly to the production process due to its physical properties. The small size of the waste mineral wool and its low compressibility and loose structure cause the waste, if directly returned to processing, to be ejected from the shaft furnace chimney as a result of the draft.

[0017] From the description of the U.S. patent application US6074967A, a method of processing material intended for the production of rock wool is known, which includes providing waste, ground material, mixing it with a fibrous binding agent and a silicate containing sodium, calcium and / or aluminum, and then forming such a mixture into solid briquettes. The fibrous binding agent preferably contains cellulose fibers, e.g., plant fibers.

[0018] From the description of the European patent application EP 2918555A1, a briquette for the production of rock wool is known, consisting of a raw material, a binder for that raw material, and an activating agent to accelerate the curing process of the briquetted raw material, wherein the raw material is waste rock wool with a fibrous morphology, and the binder is a non-fibrous inorganic binder, such as sodium silicate, the content of which ranges from 3% to 20% by weight relative to the total mass of the raw material. Gaseous carbon dioxide is used as an activating agent. The raw material may additionally contain residual material and / or residual fuels.

[0019] Known methods for processing waste strongly alkaline compounds include various unit operations and processes commonly used in chemical engineering. One of them is described in U.S. patent No. 4666689, which describes the regeneration of strongly alkaline waste by the simultaneous use of catalytic oxidation processes and the extraction of the formed oxidized products.

[0020] Another patent issued in the United States, US 5368104, describes a method for regenerating strongly alkaline waste by combining oxidation processes with operations involving UV irradiation and filtration of the oxidized and irradiated products. Another method related to the recycling of strongly alkaline waste, described in U.S. patent US 5368726, involved the oxidation of strongly alkaline waste with air and ozone, UV irradiation, and the introduction of nanofiltration operations for the products of chemical transformations.

[0021] Other known methods for the disposal of strongly alkaline waste involve reacting them with mineral acids, such as sulfuric acid (VI) or hydrochloric acid, or conducting oxidation processes of alkaline waste. Such methods have been described in U.S. patents No. US 4347225, US 4392947, US 5434329, US 5244576, US 5209828, PL 168766, and US 5246597.

[0022] Summary of the invention

[0023] The subject of the invention is a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that it comprises, in dry matter, up to 40% w / w of all alkaline compounds originating from the mineral wool and from the addition of a metal hydroxide or metal hydroxides, which constitute the sole binder of the shaped article.

[0024] In one embodiment of the invention, the shaped article comprises, in dry matter, up to 34% w / w of all alkaline compounds.

[0025] In one embodiment of the invention, the shaped article is in the form of a briquette, shaped bodies in the form of cylinders, cuboids, a granulate, or a finished aggregate.

[0026] In another embodiment of the invention, the addition of the metal hydroxide or metal hydroxides, as a binder, is: a) a pure aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table, and / or b) an industrial waste comprising impurities and an aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table and hydroxides of other alkali metals, and / or c) a solution recycled from the process of treating the shaped article produced using solution a) and / or b).

[0027] The subject of the invention is also a method for producing a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that the mineral wool is ground, homogenized, and sieved through a sieve, and uniform mineral wool fibers with a size of less than 5 mm, and in particular at most 2 mm, in an amount of 50% to 90% w / w, are mixed with a binder in an amount of 1% to 50% w / w, wherein the binder is in the form of: a) a pure aqueous solution of at least one metal hydroxide selected from the group comprising metals of group I and II of the periodic table, b) an industrial waste comprising impurities and an aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table and hydroxides of other alkali metals, and / or c) a solution recycled from the process of treating the shaped article produced using solution a) and / or b), wherein the concentration of the hydroxide or hydroxides in the binder a), b), c) is from 5% to 50% w / w, and then from the obtained wet mass, shaped articles are formed, which are subjected to a curing process, after which the shaped articles are optionally subjected to further processing through processes selected from the group comprising: thermal curing, washing, and drying, and the produced shaped article comprises, in dry matter, up to 40% w / w of all alkaline compounds originating from the mineral wool and from the addition of a metal hydroxide or metal hydroxides, which constitute the sole binder of the shaped article.

[0028] In one embodiment of the invention, mineral wool fibers sieved through a sieve with a mesh size of 5 mm, and in particular 2 mm, are used.

[0029] In another embodiment of the invention, as binder a), an aqueous solution of at least one metal hydroxide selected from the group comprising sodium, potassium, calcium, and magnesium is used.

[0030] In a further embodiment of the invention, the curing process is carried out at a temperature of 1 to 1200°C, at a relative humidity of 0 to 98% RH.

[0031] In another embodiment of the invention, the curing process is carried out for at least 10 minutes.

[0032] In yet another embodiment of the invention, the produced shaped articles, after the curing process or after further processing, if conducted, comprise in dry matter up to 40% w / w of all alkaline compounds originating from the mineral wool and the metal hydroxides constituting the binder of the shaped article.

[0033] In a further embodiment of the invention, during the curing and / or drying stage of the shaped articles, water is recovered in the form of water vapor, and the recycled water is used in the washing stage of the shaped articles.

[0034] The subject of the invention is also a production line for carrying out the method defined above for producing a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that it comprises a homogenizer fed with waste mineral wool, equipped with a mill and sieves, wherein the homogenizer is connected to a mixer additionally fed with a binder solution, and the mixer is provided with a line for transporting the wet mass to a forming device that feeds the wet shaped articles to a curing chamber, optionally equipped with heating elements, and further wherein the curing chamber is optionally connected by means of transport with a washing unit, and subsequently with a drying chamber, where the shaped articles are introduced.

[0035] In one embodiment of the invention, the curing chamber is connected directly by means of transport with a warehouse for cured shaped articles, or is connected with the warehouse indirectly, through the washing unit, and subsequently the drying chamber.

[0036] In another embodiment of the invention, the forming device can be in the form of a vibropress, briquetting machine, molding machine, forming belt, granulator, agglomerator, roller-belt press, belt-type die cutter, or extruder.

[0037] The subject of the invention in the form of a production line / plant for carrying out the presented method is shown in an exemplary embodiment in Fig. 1 and Fig. 2, as a block diagram of consecutive, interconnected sections of such a production line, where Fig. 1 shows a simplified production line containing only the necessary (obligatory) sections, and Fig. 2 shows a more complex production line with additional, optional sections.

[0038] The essence of the invention is the production of a shaped article from mineral wool waste, using a special composition of additives such as binders. A very simple binder composition is used - it is a hydroxide solution, devoid of other additives, or strongly alkaline waste, i.e., post-production materials from the refining, petrochemical, and other technological processes, where a solution of chemical compounds with a strongly alkaline character is a by-product.

[0039] For the purposes of the invention, a shaped article should be understood as various types of mineral wool agglomerates or their mixtures, including pellets and granulates or other solid shapes formed by forming / pressing. The shaped article produced by the method according to the invention is primarily suitable for the production of mineral wool, but all other applications are also possible in which the shaped article is primarily used due to the excellent binding properties of the applied binder. Furthermore, the binder used in the invention allows for the complete elimination of problems associated with the use of conventional binders for forming prefabricated elements, and the applied manufacturing technology is more economical and ecological. The binder used in the shaped article according to the invention contains either a pure solution of metal hydroxides themselves or a strongly alkaline waste - a post-production solution with an alkaline reaction. The shaped article does not contain other binding substances, other binders, or additives to the binder.

[0040] Detailed description

[0041] Shaped articles according to the invention are produced from two components : mineral wool, which can be added in the range of 50-90% w / w, and a binder in the form of aqueous solutions of metal hydroxides from the s-block of the periodic table (group I and II of the periodic table), including from the group comprising hydroxides of: sodium, potassium, lithium, magnesium, and calcium, or their mixtures, with a percentage concentration ranging from 1 to 50% w / w, for example from 5% to 50%, preferably from 10% to 25% w / w, while the quantitative compositions of the shaped article indicated in the present invention are generally given in weight percentages. As the binder, waste, post-production alkaline compound solutions, as discussed above, with analogous concentrations of alkaline compounds as mentioned above, can also be used. The binder may also be a mixture of pure hydroxide solutions and waste, post-production alkaline compound solutions.

[0042] In another embodiment of the invention, post-production solutions of alkaline compounds can be subjected to pre-treatment to separate only the hydroxide solutions of group I and II metals of the periodic table, which are most beneficial for use as a binder in the shaped article.

[0043] In the method according to the invention, from 1% to 50% by weight of the aforementioned aqueous solution of hydroxide or mixture of hydroxides is added to the ground mineral wool, for example from 5% to 30% or from 10% to 25% of the aqueous hydroxide solution. This combination ensures an optimal chemical composition, which is of great importance for mineral wool producers. The chemical composition of the shaped article is more than 99% identical with respect to the chemical composition of finished mineral wool produced commercially from natural materials. The table below presents the chemical composition of ecological shaped articles produced by the method according to the invention from waste mineral wool and a hydroxide binder. Moreover, the shaped articles produced by the presented method exhibit exceptionally good compressive strength properties, reaching values of at least 4 MPa, even from 4 MPa up to 60 MPa.

[0044] Table 1. Chemical composition of the shaped articles according to the invention, produced from waste mineral wool, by the method according to Example 1 (variant with the addition of 25% w / w of sodium hydroxide)

[0045] The table above presents the results of tests on the chemical composition of the shaped article obtained by the method according to the invention, conducted using X-ray fluorescence spectrometry with wavelength dispersion. This is a commonly used method in the industry of processing mineral wool and forming shaped articles. The composition of the article also includes values of alkaline compounds (compounds of metals from groups I and II of the periodic table of elements), which should not be exceeded in the shaped articles and the method according to the invention.

[0046] Mineral wool is used in the form of waste in any form, originating from all industrial fields where mineral wool is used / produced. Before use, any type of wool, fiber, particles, or sinters of the raw material must be of appropriate size and, after sieving, should pass through sieves with a mesh size of 5 mm, preferably below 2 mm. Raw material that does not pass through the sieve mesh is returned for further grinding and homogenization.

[0047] The sole binder for the shaped article according to the invention are solutions of metal hydroxides, especially from the s-block of the periodic table (group I and II of the periodic table of elements), for example: lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, and strontium. The role of the binder can also be fulfilled by strongly alkaline waste, i.e., solutions of compounds with an alkaline character originating from postproduction processes of the crude oil refining industry, petrochemical industry, and any other chemical process where such compounds can be utilized, for example: hydroxides, oxides, or salts of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, and strontium. The purpose of the binder is to bind the mineral wool fibers as a result of a chemical reaction.

[0048] In the method according to the invention, in the first stage, the mineral wool is ground and homogenized, so that the fibers are uniform and of similar sizes, preferably less than 5 mm, and in particular 2 mm and less than 2 mm. The uniform mineral wool raw material, preferably after sieving, should pass through sieves with a mesh size of 2 mm and less than 2 mm. The process is carried out under normal conditions.

[0049] The homogenized mineral wool fibers are then mixed with the binder in appropriate proportions to form a mixture - the wet mass of the shaped article. The method according to the invention allows for the production of the final product - a dry article, using such amounts of ingredients that the wet mass has a reduced humidity or an increased humidity. The resulting mixture is then formed into the appropriate shape using various devices and unit operations. In the next stage, the formed articles (shaped bodies) are subjected to a curing process at a temperature from 1 to 1200°C, for example from 10°C to 800°C, from 10°C to 600°C, from 10°C to 100°C or from 40°C to 400°C, at a relative humidity from 0 to 98% RH, for example from 3 or from 5 to 80% RH.

[0050] During the curing of the articles from the mass, water is removed and oxidation processes occur, during which oxides, for example of carbon, sulfur, or nitrogen, can be formed. The oxides released during the curing of the shaped articles are subjected to capture processes in an absorber, so that minimal or zero amounts of emitted gases are released into the atmosphere. The capture, according to the invention, can be carried out by all known methods, for example, absorption in water, absorption in aqueous solutions of hydroxides or salts of calcium, sodium, or potassium, or wet flue gas desulfurization. In this technology stage, at least 90% of the produced oxides are absorbed and not released into the atmosphere.

[0051] After the curing stage of the shaped article, the wet mass is almost completely deprived of water, e.g., at least 90% of the water is evaporated, most preferably at least 95% of the water is evaporated from the mass of the article, so the dry product after curing contains less than 10% water, or less than 5% water.

[0052] After curing and drying, the shaped articles are characterized by physical and chemical properties that allow for their use in the mineral wool production process. They have adequate strength and do not crumble.

[0053] In a variant of the invention, after curing the shaped articles, the articles are washed with water to remove unbound alkaline compounds. This process can be carried out by various methods, for example by immersing the shaped articles in a tank with water for a specified time and removing them, by spraying the shaped articles with water, by using pressure washers, by passing the shaped articles on a belt through a water bath for washing, and others. All known methods for washing solid, including porous, materials are permissible in the technological process of producing the shaped articles by the discussed method. The water with the washed-out alkaline compounds (metal hydroxides) can be recycled back into the process. The washing water is used to prepare a new batch of binder used to produce the shaped articles. The wet articles after washing can be directed to a drying device, for example a drying chamber heated by heat from biomass combustion, an electric dryer, or a furnace heated by flue gases. The evaporated water, initially in the form of water vapor, is passed through a gas absorber and captured in recuperators and condensers. The recovered water is also recycled back into the process, either for washing the articles or for preparing the binder solution. By recycling the alkalis and water, the consumption of these raw materials is reduced, and the entire process becomes more environmentally friendly. Drying can proceed at a temperature from 1 to 1200°C or from 1°C to 800°C, for example from 100°C to 500°C, from 20°C to 100°C or from 5°C to 400°C, at a relative humidity from 0 to 98% RH, for example from 3 or from 5 to 80% RH. The water vapor released in the process is captured, condensed, for example in condensers or recuperators for solvents, and recycled back into the process for reuse in creating a new batch of binder. When drying is conducted at a high temperature, i.e., at a temperature above 800°C, e.g., in the range from 800°C up to 1200°C, this process can be called calcination.

[0054] The method of producing the shaped article according to the invention is carried out on an industrial scale using known but appropriately adapted devices connected in a production line.

[0055] The production line according to the invention comprises at least the following elements: at the inlet, a homogenizer 1 fed with appropriately prepared raw material originating from waste mineral wool (WM), which raw material is subjected to grinding and sieving and possibly recycling if it does not meet the specified requirements. Next, the purified, ground mineral wool is fed to a mixer 2, which is additionally fed with a binder (S), where the mixing of mineral wool with the binder takes place. The mass obtained in the mixer is supplied to a forming device 3 for shaping the glass wool mass into shaped articles, from where the wet articles are fed to a curing chamber 4, in which the shaped bodies undergo binding, consolidation, and drying. In the final stage, the aging (curing) chamber is emptied, and the articles ready for processing into full-value mineral wool are fed to a warehouse 5, where the shaped articles are collected at the end of the technological process. The term warehouse 5 should also be understood as any space or device, such as a packaging line, or a line for portioning and receiving / further transport of the shaped articles. The simple variant of the production line described above is shown schematically in Fig. 1.

[0056] Optionally, the production line before the homogenizer 1 includes a sorter 9, where segregation and cleaning of the waste mineral wool occur.

[0057] Optionally, the production line after the curing chamber 4 includes a washing unit 6 fed with water (W), where unbound alkaline compounds (binder) are washed out from the articles. The water-washed binder is recycled to the process as a stream (SZ) (recycled binder) and mixed with the binder stream (S) introduced into the mixer 2. In the final stage, the briquettes are directed to a drying chamber 7. The water vapor released during curing and drying (recycled water - WZ) can either be collected in an absorber 8 for reuse in operations and unit processes requiring the use of water or be directly recycled to the washing stage of the shaped articles. The dried shaped articles as prefabricated elements ready for later processing into full-value mineral wool are sent by means of transport to a warehouse 5, where they are collected at the end of the technological process. A more complex variant of the production line according to the invention is shown in Fig. 2.

[0058] Fig. 2 shows with arrows the transport of raw materials and shaped articles, e.g., mineral wool WM introduced into the sorter 9 and homogenizer 1, binder S supplied to the mixer 2, where optionally recycled binder SZ from the washing unit 6 is also added. Water W or recycled water WZ from the curing chamber 4 or from the drying chamber 7 is introduced into the washing unit 6. A dashed line indicates the flow of recycled water in the form of vapor.

[0059] Example 1

[0060] Production of shaped articles from a mass with reduced humidity using mild curing conditions and NaOH or KOH as a binder.

[0061] Waste mineral wool is ground and homogenized to a form such that the particles of mineral wool, after sieving, pass through sieve meshes with dimensions equal to or less than 2 mm. An aqueous solution of a metal hydroxide is then prepared, in one variant sodium, in a second variant potassium, at a concentration of 10% w / w in water. The water used does not have to be pre-treated (e.g., by distillation or demineralization). It should be clean and come from the water intake used for the production of any other type of building material . The hydroxide solution in water is mixed with a suitably ground mineral wool in the proportions of 75% or 80% wool and 25% or 20% hydroxide solution, respectively. The final content of all alkaline compounds in the dry product should not exceed 34%. After homogenizing the mixture (proper mixing of the mass), it is usually formed into a hexagonal prism shape with an approximate volume of 1 dm3(the shape and volume of the article's form depend on the requirements related to the further processing of the shaped article to produce mineral wool). The moisture (water) content in the mass before curing should, for example, be about 18 - 22%. In the final stage of the wet process, the formed mass is subjected to the curing process. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and strength properties. The curing process leading to the formation of the final product should take place under specific conditions allowing for efficient production, preferably at a temperature and humidity not exceeding 130°C and 5% RH.

[0062] In such ambient conditions, the shaped articles should cure in a time no shorter than 2 h (until the required strength properties are achieved). The finished article produced by this method should be stored in air-dry conditions until its use in the mineral wool production process. In this stage, the water vapor released from the briquettes can be captured in recuperators and directed, for example, to the preparation of the next batch of binder.

[0063] Example 2

[0064] Production of a shaped article from a mass with reduced humidity using mild curing conditions and NaOH or KOH as a binder.

[0065] In the example, a raw material (wet mass of the article) with a higher humidity was used and a product meeting the physicochemical and mechanical assumptions for an ecological shaped article was obtained. Waste mineral wool was ground and homogenized to a form such that the mineral wool particles after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, an aqueous solution of a metal hydroxide is prepared, for example in the first variant sodium, and in the second variant potassium, at a concentration of 10% w / w in water. The water used does not have to be pre-treated (e.g., by distillation or demineralization). It should be clean and come from the water intake used for the production of any other type of building material. After dissolving the hydroxide in water, the resulting solution is mixed with a suitably ground mineral wool in proportions of 75% or 80% wool and 25% or 20% hydroxide solution (in the first variant sodium and in the second potassium). The final content of all alkaline compounds in the dry product should not exceed 34%. After homogenizing the mixture (proper mixing of the mass), it is poured into a mold to create a shaped article in the shape of a hexagonal prism with a volume of about 1 dm3. The moisture (water) content in the wet mass before curing should be about 18-22%. In the final stage of the process, the wet, formed mass is subjected to the curing process. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and mechanical properties. The curing process leading to the formation of the final product should take place in specific conditions allowing for efficient production, preferably at a temperature and humidity not exceeding 55°C and 80-85% RH. In such ambient conditions, the shaped articles should cure in a time not shorter than 72 h (until the required strength properties are reached). The finished article produced by this method should be stored in air-dry conditions until its use in the mineral wool production process. In this stage, the water vapor released from the briquettes can be captured in recuperators and directed, for example, to the preparation of the next batch of binder.

[0066] Example 3

[0067] Production of shaped articles from a mass with increased humidity at a slightly elevated curing temperature and NaOH or KOH as a binder.

[0068] Raw materials with higher humidity were used and a product meeting the physicochemical and mechanical assumptions for an ecological shaped article was obtained. Waste mineral wool is ground and homogenized to a form such that the mineral wool particles after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, an aqueous solution of a metal hydroxide is prepared, in the first sodium variant, and in the second potassium variant, at a concentration of 25% w / w in water. The water used does not have to be pre-treated (e.g., by distillation or demineralization). It should be clean and come from the water intake used for the production of any other type of building material. After dissolving the hydroxide in water, the solution is mixed with a suitably ground mineral wool in proportions of 70% wool and 30% hydroxide solution (in two variants). The final content of alkaline compounds in the dry product should not exceed 34% w / w. After homogenizing the mixture (proper mixing of the mass), it is poured into a mold to form a shaped article in a suitable shape (cubic, spherical, rounded, rod-shaped, etc.) with a volume of about 1 dm3. The water content in the mass should be high enough to allow it to be poured into the mold while maintaining its viscosity and density. In the final stage of the wet process, the formed mass is subjected to the curing process. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and mechanical properties. The curing process leading to the formation of the final product should take place under specific conditions allowing for efficient production, preferably at a temperature and humidity in the range of 120 - 130°C and 0-5% RH. In such ambient conditions, the shaped articles should cure in a time not shorter than 2 h (until the required strength properties are achieved). The finished article produced by this method should be stored in air-dry conditions until its use in the mineral wool production process. In this stage, the water vapor released from the briquettes can be captured in recuperators and directed, for example, to the preparation of the next batch of binder.

[0069] Example 4

[0070] Production of shaped articles from a mass with increased humidity at a high curing temperature and NaOH as a binder.

[0071] A shaped article was produced using raw materials with higher humidity, and a product meeting the physicochemical and mechanical assumptions for an ecological shaped article was obtained. Waste mineral wool was ground and homogenized to a form such that the mineral wool particles after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, an aqueous solution of a metal hydroxide, for example sodium, is prepared at a concentration of 25% w / w in water. The water used does not have to be pretreated (e.g., by distillation or demineralization). It should be clean and come from the water intake used for the production of any other type of building material. After dissolving the hydroxide in water, the solution is mixed with a suitably ground mineral wool in proportions of 50% wool and 50% hydroxide solution. The final content of alkaline compounds in the dry article should not exceed 34%. After homogenizing the mixture (proper mixing of the mass), it is poured into a mold to form a shaped article in a suitable shape with an appropriate volume of approximately 1 dm3. The water content in the mass should be high enough to allow it to be poured into the mold while maintaining its viscosity and density. In the final stage of the wet process, the formed mass is subjected to the curing process. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and mechanical properties. The curing process leading to the formation of the final product should take place under specific conditions allowing for efficient production, preferably at a temperature and humidity in the range of 750 - 1200°C and 0-3% RH. In such ambient conditions, the shaped articles should cure in a time not shorter than 10 min. Using the presented method of producing shaped articles, the temperature at which the material is to cure should be gradually increased - it is necessary to apply a linear temperature increase over a specified period (the temperature increase should be linearly distributed over 48h). Thanks to this, the problem of "shrinkage" of the material caused by exposing the wet mass of the shaped article to high temperature and too rapid loss of water from the mass of the article (until the required strength properties are achieved) is eliminated. After reaching the maximum temperature, e.g., 1200°C, the material should also be gradually cooled, and the temperature reduction should last at least 12 h. The finished article produced by this method should be stored in air-dry conditions until its use in the mineral wool production process. In this stage, the water vapor released from the briquettes can be captured in recuperators and directed, for example, to the preparation of the next batch of binder.

[0072] Example 5

[0073] The shaped articles produced in the preceding Examples 1, 2, 3, and 4 were subjected to additional treatment. The formed and dry briquettes were directed to a washing unit, where the material was washed with water (e.g., using a washer, where it was immersed in water for several minutes), to wash out the unbound alkaline hydroxides used as the briquette binder. The solution of washed-out hydroxides (washing liquor) was then recycled to the process by mixing the return stream with the fresh binder batch stream fed to the mixer. The washing liquor was optionally concentrated before reuse. The wet briquettes were optionally subjected to a drying process, for example, in conditions of 100 - 120°C and 5% RH for a time allowing for complete drying of the material, so that the moisture content in the finished material did not exceed 10% RH. The moisture released from the briquettes, captured by a solvent recuperator, during the drying process is optionally recycled to the process, for example, to the process of washing out the binder in the washing unit. The finished shaped article produced by this method should be stored in air-dry conditions until its use in the mineral wool production process.

[0074] Example 6

[0075] Production of briquettes from a mass with reduced humidity using mild curing conditions and post-industrial sulfuric lyes from the purification of petroleum products in refineries, for example after olefin pyrolysis, as a binder.

[0076] Waste mineral wool is cleaned, ground, and homogenized to a form such that the particles of mineral wool after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, a post-production sulfuric lye, not previously cleaned or subjected to any processes or unit operations, is added. The lye solution is mixed with mineral wool in such proportions that a compact, plastic mass is formed, and the final content of all alkaline compounds in the dry product does not exceed 40%, for example 70-75% wool and 20-25% lyes. In the next stage, the wet mass is subjected to a forming process into briquettes. It is usually formed into a hexagonal prism shape with an approximate volume of 1 dm3(the shape and volume of the briquette's form depend on the requirements related to the further processing of briquettes / aggregates). The moisture (water) content in the mass before curing should, for example, be about 18 - 22%. In the next stage, the briquettes are subjected to curing in a chamber with increasing temperature, for example from 300 - 450°C and 5% RH. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and strength properties. In such ambient conditions, the briquettes should cure in a time not shorter than 60 minutes (until the required strength properties are achieved). The off-gases released during the process are captured and, for example, subjected to a catalytic oxidation process and absorption into inorganic acids. In the next stage, the dry mass is re-sprayed with water to wash out unreacted and unbound alkalis. The aqueous alkali solution is recycled back to the process by combining the return lye stream with the fresh binder stream. In the final stage of the wet process, the formed mass is re-dried in a drying chamber at a temperature of, for example, 70 - 100°C and 0-5% RH. The finished briquette produced by this method should be stored in air-dry conditions until its use in the mineral wool production process. Example 7

[0077] Production of briquettes from a mass with reduced humidity using critical curing conditions and post-production lyes from, for example, chlorination, esterification, oxidation, alkylation, or sulfonation technologies as a binder.

[0078] Waste mineral wool is cleaned, ground, and homogenized to a form such that the particles of mineral wool after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, a post-production lye, not previously cleaned or subjected to any processes or unit operations, is added. The lye solution is mixed with mineral wool in such proportions that a compact, plastic mass is formed, and the final content of all alkaline compounds in the dry product does not exceed 40%, for example 80% wool and 20% lyes. In the next stage, the wet mass is subjected to a forming process into briquettes. It is usually formed into a hexagonal prism shape with an approximate volume of 1 dm3(the shape and volume of the briquette's form depend on the requirements related to the further processing of briquettes / aggregates). The moisture (water) content in the mass before curing should, for example, be about 18 - 22%. In the next stage, the briquettes are subjected to curing in a chamber with increasing temperature, for example from 800 to 1200°C and 0-3% RH. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and strength properties. In such ambient conditions, the briquettes / aggregates should cure in a time not shorter than 10 minutes (until the required strength properties are achieved). The off-gases released during the process are captured and, for example, subjected to catalytic oxidation processes and absorption into inorganic acids. In the next stage, the dry mass is resprayed with water to wash out unreacted and unbound alkalis. The aqueous alkali solution is recycled back to the process by combining the return lye stream with the fresh stream. In the final stage of the wet process, the formed mass is re-dried in a drying chamber. The finished briquette produced by this method should be stored in air-dry conditions until its use in the mineral wool production process.

[0079] Example 8

[0080] Production of briquettes from a mass with increased humidity at a high curing temperature and post-industrial sulfuric lyes from the purification of petroleum products in refineries, for example after olefin pyrolysis, as a binder. Waste mineral wool is cleaned, ground, and homogenized to a form such that the particles of mineral wool after sieving pass through sieve meshes with dimensions equal to or less than 2 mm. Then, a post-production sulfuric lye, not previously cleaned or subjected to any processes or unit operations, is added. The lye solution is mixed with mineral wool in such proportions that a compact, plastic mass is formed, and the final content of all alkaline compounds in the dry product does not exceed 40%, for example 50% wool and 50% lyes. In the next stage, the wet mass is subjected to a forming process into briquettes. It is usually formed into a hexagonal prism shape with an approximate volume of 1 dm3(the shape and volume of the briquette's form depend on the requirements related to the further processing of briquettes / aggregates). In the next stage, the briquettes are subjected to curing in a chamber with increasing temperature, for example from 800 to 1200°C and 0-3% RH. During this time, a chemical reaction occurs that binds the reactants and joins the mineral wool particles into a finished product meeting the assumed criteria of chemical composition and strength properties. In such ambient conditions, the briquettes should cure in a time not shorter than 10 min (until the required strength properties are achieved). The off-gases released during the process are captured and, for example, subjected to catalytic oxidation processes and absorption into inorganic acids. In the next stage, the dry mass is re-sprayed with water to wash out unreacted and unbound alkalis. The aqueous alkali solution is recycled back to the process by combining the return lye stream with the fresh batch. In the final stage of the wet process, the formed mass is re-dried in a drying chamber. The finished briquette produced by this method should be stored in air-dry conditions until its use in the mineral wool production process.

[0081] Example 9

[0082] Production of a finished aggregate (granulate) from a mass with reduced humidity using mild curing conditions and post-industrial sulfuric lyes from the purification of petroleum products in refineries, for example after olefin pyrolysis, as a binder.

[0083] Waste mineral wool is cleaned, ground, and homogenized. Then, a post-production sulfuric lye, not previously cleaned or subjected to any processes or unit operations, is added. The lye solution is mixed with mineral wool in such proportions that a compact, plastic mass is formed, and the final content of all alkaline compounds in the dry product does not exceed 40%, preferably 34%, for example 75% mineral wool and 25% binder. In the next stage, the wet mass is subjected to a forming process into an aggregate. The moisture (water) content in the mass before curing should, for example, be about 18 - 22%. In the next stage, the briquettes are subjected to curing in a chamber with increasing temperature, for example from 300 to 450°C and 5% RH. In such ambient conditions, the aggregate cures in a time not shorter than 30 min. In the next stage, the dry mass is re-sprayed with water to wash out unreacted and unbound alkalis. The aqueous alkali solution is recycled back to the process by combining the return lye stream with the fresh one. In the final stage of the wet process, the formed mass is re-dried in a drying chamber at a temperature of 90-110°C, 5% RH. The finished granulate (aggregate) produced by this method should be stored in air-dry conditions until its use.

Claims

Patent Claims1. A shaped article comprising mineral wool, preferably waste mineral wool, characterized in that it comprises, in dry matter, up to 40% w / w of all alkaline compounds originating from the mineral wool and from an addition of a metal hydroxide or metal hydroxides, which constitute the sole binder of the shaped article.

2. The shaped article according to claim 1, characterized in that it comprises, in dry matter, up to 34% w / w of all alkaline compounds.

3. The shaped article according to claim 1 or 2, characterized in that it is in the form of a briquette, shaped bodies in the form of cylinders or cuboids, a granulate, or a finished aggregate.

4. The shaped article according to claim 1 or 2 or 3, characterized in that the addition of the metal hydroxide or metal hydroxides, as a binder, is: a) a pure aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table, and / or b) an industrial waste comprising impurities and an aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table and hydroxides of other alkali metals, and / or c) a solution recycled from the process of treating the shaped article produced using solution a) and / or b).

5. A method for producing a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that the mineral wool is ground, homogenized, and sieved through a sieve, and uniform mineral wool fibers with a size of less than 5 mm, and in particular at most 2 mm, in an amount of 50% to 90% w / w, are mixed with a binder in an amount of 1% to 50% w / w, wherein the binder is in the form of: a) a pure aqueous solution of at least one metal hydroxide selected from the group comprising metals of group I and II of the periodic table,b) an industrial waste comprising impurities and an aqueous solution of a hydroxide or hydroxides of metals from the group comprising metals of group I and II of the periodic table and hydroxides of other alkali metals, and / or c) a solution recycled from the process of treating the shaped article produced using solution a) and / or b), wherein the concentration of the hydroxide or hydroxides in the binder a), b), c) is from 5% to 50% w / w, and then from the obtained wet mass, shaped articles are formed, which are subjected to a curing process, after which the shaped articles are optionally subjected to further processing through processes selected from the group comprising: thermal curing, washing, and drying, and the produced shaped article comprises, in dry matter, up to 40% w / w of all alkaline compounds originating from the mineral wool and from the addition of a metal hydroxide or metal hydroxides, which constitute the sole binder of the shaped article.

6. The method according to claim 5, characterized in that mineral wool fibers sieved through a sieve with a mesh size of 5 mm, and in particular 2 mm, are used.

7. The method according to claim 5 or 6, characterized in that as binder a), an aqueous solution of at least one metal hydroxide selected from the group comprising sodium, potassium, calcium, and magnesium is used.

8. The method according to claim 5 or 6 or 7, characterized in that the curing process is carried out at a temperature of 1 to 1200°C, at a relative humidity of 0 to 98% RH.

9. The method according to any one of claims 5 to 8, characterized in that the curing process is carried out for at least 10 minutes.

10. The method according to any one of claims 5 to 9, characterized in that the produced shaped articles, after the curing process or after further processing, if conducted, comprise in dry matter up to 40% w / w of all alkaline compounds originating from the mineral wool and the metal hydroxides constituting the binder of the shaped article.

11. The method according to any one of claims 5 to 10, characterized in that during the curing and / or drying stage of the shaped articles, water is recovered in theform of water vapor, and the recycled water is used in the washing stage of the shaped articles.

12. A production line for carrying out the method defined in claim 5 for producing a shaped article comprising mineral wool, preferably waste mineral wool, characterized in that it comprises a homogenizer (1) fed with waste mineral wool, equipped with a mill and sieves, wherein the homogenizer (1) is connected to a mixer (2) additionally fed with a binder solution, and the mixer (2) is provided with a line for transporting the wet mass to a forming device (3) that feeds the wet shaped articles to a curing chamber (4), optionally equipped with heating elements, and further wherein the curing chamber is optionally connected by means of transport with a washing unit (6), and subsequently with a drying chamber (7), where the shaped articles are introduced.

13. The production line according to claim 12, characterized in that the curing chamber (4) is connected directly by means of transport with a warehouse (5) for cured shaped articles, or is connected with the warehouse (5) indirectly, through the washing unit (6), and subsequently the drying chamber (7).

14. The production line according to claim 12 or 13, characterized in that the forming device can be in the form of a vibropress, briquetting machine, molding machine, forming belt, granulator, agglomerator, roller-belt press, belt-type die cutter, or extruder.

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