A process for the recovery of glass and minerals from recycling waste for use in cement making and construction

Abstract

The invention is an innovative upcycling system that converts industrial recycling waste into Recovered Glass Minerals (RGMs) — a sustainable additive for low-clinker cement production or other construction-related applications. The process of the invention provides a local, low-CO2 alternative to conventional additives such as blast furnace slag and silica fume. The processing system mechanically removes regulated heavy metals from recycling waste streams, ensuring compliance with regulatory standards for cement production. The process operates without toxic chemicals or high energy consumption, making it an environmentally friendly solution. It employs a multi-step separation process, including air-based fluid dynamics, magnetic separation, ultrasonic cavitation, and heavy media separation. These steps efficiently extract plastics, metals, and contaminants while isolating high-purity RGMs for cement production. Designed as a modular, scalable solution, the system leverages readily available industrial equipment for rapid deployment and commercialization. By transforming waste into a valuable cement additive, this process enhances circular economy practices, strengthens local supply chains for additives, and contributes to the decarbonization of the construction industry.

Description

[0001] A PROCESS FOR THE RECOVERY OF GLASS AND MINERALS FROM RECYCLING WASTE FOR USE IN CEMENT MAKING AND CONSTRUCTION

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to recovering glass and mineral materials (e.g., crushed windscreen glass, other glass materials, ceramics, etc.) from the waste generated from the recycling of end-of-life motor vehicles and other types of post-consumer and production waste, for potential use as an additive for producing low clinker cement.

[0004] BACKGROUND OF THE INVENTION

[0005] The ongoing urbanisation of the world (new cities, roads, rail, bridges, etc.) and a clean energy transition (new wind farms, solar plants, etc.) requires new construction for which cement is a key component. The manufacturing of cement involves a complex industrial process that begins with the extraction of raw materials and culminates in the production of the final product - a process which emits significant CO2emissions. Here's a detailed overview of the steps involved:

[0006] 1. Extraction of Raw Materials: limestone, clay, shale, and other materials such as sand, iron ore, and bauxite, extracted from quarries and transported to the cement plant.

[0007] 2. Crushing and Grinding: The extracted raw materials are crushed and ground into fine powder to facilitate the subsequent process.

[0008] 3. Raw Meal Preparation: The crushed and ground raw materials are blended in precise proportions to form a homogeneous mixture known as raw meal.

[0009] 4. Clinker Production: The raw meal is fed into a rotary kiln, where it undergoes a high- temperature process known as calcination or pyro-processing, causing chemical reactions that result in the formation of nodular clinker.

[0010] 5. Clinker Grinding: The clinker is cooled and then ground along with gypsum and additives such as Supplementary Cementitious Materials (SCMs) to produce cement.6. Packaging and Distribution: The finely ground cement is stored in silos before being packaged in bags or bulk containers for distribution to construction sites, ready-mix concrete plants, and other end-users.

[0011] Cement manufacturing accounts for about 8% of global CO2 emissions from the annual production of about 4 billion tonnes of cement.1In the Clinker Production step, the calcination process alone contributes to around 60-65% of the total emissions from cement production, while fossil fuel combustion in kilns accounts for about 30-35%. Transportation-related emissions add an estimated 5-10%.2To address this, initiatives such as using alternative fuels (up to 40% reduction), optimizing kiln efficiency (up to 25% reduction), and employing alternative raw materials (up to 10% reduction) are crucial. Implementing carbon capture and storage technologies could potentially mitigate up to 80-90% of emissions from cement plants.

[0012] In Switzerland, cement producers have actively worked on reducing emissions over the years and achieved a total scope 1 emission reduction of 38% compared to the 1990 baseline. The emission reductions were primarily achieved through energy efficiency measures, a shift from primary fossil fuels to waste fuels, increasing the share of biomass in the fuel mix, and a shift towards lower-clinker cements. The Swiss emission intensity of clinker production is 762 kg C02 / tonne clinker, 10% lower than the global average of 850 kg C02 / tonne clinker. However, more needs to be done in order for Switzerland (and other countries) to reach the mandated Net Zero goals.3

[0013] SCMs like fly ash, blast furnace slag, and silica fume, by-products of industrial processes, offer a sustainable solution for cement production. Integrating SCMs reduces the need for clinker, cutting carbon emissions by up to 25%.4Additionally, their use decreases energy consumption by 15-20% per tonne of cement. Crucially, by repurposing industrial waste, SCMs promote circular economy principles, reducing landfill reliance and conserving resources. In sum, SCMs not only mitigate environmental impact but also exemplify the potential of waste utilization in sustainable construction practices.

[0014] However, increasing the sourcing SCMs for cement making comes with the following challenges:

[0015] • In the 27 European Union countries, the latest data from European Cement Association shows that low clinker cements already have about 65% market share, however this share has been stagnant at this level for the last 5 years, indicating that the available SCMs (like blast furnace slags and fly ash) are already being utilised to the fullest possible extent and the region is looking for new alternatives.5• Moreover, the European Cement Association estimates that the availability of recycled materials (like blast furnace slag and fly ash) being used as SCMs will decline in the coming years due to the decarbonisation of steel making and power generation - trends also seen in other parts of the world.6

[0016] • The use of natural materials like limestone and pozzolans as SCMs still require the polluting practice of mining these materials from quarries which causes adverse environmental impact. Moreover, it has become increasingly difficult to get authorisations for new mines and quarries or even to expand existing ones, bringing uncertainty on the long-term materials supply needed for producing low-clinker cement, as noted by the CEO of Holcim Switzerland.7

[0017] On average, cement includes less than 5% of these above-mentioned materials, and the cement industry is targeting to increase this ratio to 10% of these materials in 2030, 15% by 2040, and 20% by 2050, as per the Portland Cement Association’s roadmap. Hence, SCM demand growth will spur the use of alternative SCMs.8

[0018] In Switzerland, regulatory limits imposed by the Waste Ordinance (VeVA) and aligned with European Union standards dictate the permissible levels of contaminants in Supplementary Cementitious Materials (SCMs) used in cement production. For instance, VeVA sets specific thresholds for heavy metals such as cadmium, lead, and mercury, typically ranging from 50 to 100 milligrams per kilogram (mg / kg) depending on the material and its intended application. VeVA also mandates strict criteria for parameters like sulphate content, alkali content, and loss on ignition, ensuring that SCMs meet quality standards and pose minimal risk to human health and the environment. However, meeting these stringent criteria can pose challenges for sourcing SCMs and may require industries to invest in advanced technologies for waste management and quality control. More specifically, the limits that have to be met by materials to be used as SCMs are compiled in the Ordinance on the Avoidance and the Disposal of Waste (Waste Ordinance, ADWO) of 4 December 2015 (Status as of 1 January 2025).9

[0019] In order to enable a circular economy, a lot of research has been done on transforming waste into a source of new raw materials - not just in construction, but also in waste management and mining. The present invention not only focuses on techno-economic aspects for such endeavours, but also to meet the tight regulatory conditions around reuse of materials as mentioned above.A number of prior art documents have addressed the recovery of minerals from waste feedstocks, including the use of ultrasonic treatment and density-based separation techniques.

[0020] For example, CN111410449A ("Method for preparing glass powder for cement from waste glass") describes a process for producing glass powder from waste glass for use in cement, involving crushing, grinding to sub-micron size, ultrasonic dispersion, and removal of contaminants, but does not address the removal of metallic contaminants from mineral particles of larger size or the use of heavy media separation.

[0021] W02025039088A1 ("Method for recovering valuable elements from waste and use thereof') discloses the recovery of valuable elements from waste, including the use of density-based separation, but does not teach the combination of ultrasonic cavitation and heavy media separation for the removal of metallic contaminants from mineral waste.

[0022] "Evaluation of shredder residue as cement manufacturing feedstock" (Boughton et al., 2007) discusses the use of shredder residue as a feedstock for cement, including density-based separation, but does not disclose ultrasonic treatment for contaminant removal.

[0023] "Waste-Printed Circuit Board Recycling: Polymer Composites and Geopolymers" (ACS Omega 2020, 5, 17850-17856) reviews mechanical-physical recycling methods for electronic waste, including density and electrostatic separation, but does not address the combined use of ultrasonic cavitation and heavy media separation for mineral recovery from contaminated waste.

[0024] The use of ultrasound-based cavitation has been previously studied and published for the processing of waste feedstocks. The following patents focus on the use of ultrasound for mineral recovery and separation, however none of them focus on the development of an integrated system to separate out the Recovered Glass and Minerals (RGMs), notably from recycling waste by the removal of the fine mixed metallic contaminants, for use as an SCM:

[0025] It is known from CN104711107 A that ultrasonic waves (10-38 kHz) are used to separate and recover abrasive mineral particles and cutting swarf from silicon waste slurry.

[0026] KR101045815 B1 discloses ultrasound combined with heavy liquids for silicon separation via specific gravity.

[0027] CN102161486 A discloses combined ultrasonic treatment with heavy-fluid dispersion for silicon and silicon carbide separation from waste mortar.US8354088 B2 discloses the use of ultrasound combined with density-based settling for silicon recovery from photovoltaic industry waste.

[0028] CN107416851 B teaches the use of ultrasound agitation (25-26 kHz) to extract silica from fly ash using a combination of ball milling, acid leaching, and calcination treatments to prepare sodium silicate.

[0029] All these patents explicitly disclose the use of ultrasound as a key part of their mineral separation or recovery processes, but none of them focus on the recovery of glass and other minerals from recycling waste particularly to remove contaminant metals and then use the resulting product as an SCM in cement production.

[0030] The objective technical problem addressed by the present invention is to provide an improved method for recovering mineral fractions from contaminated waste feedstocks, in particular to efficiently remove metallic contaminants, including fine metallic particles and dust, from mineral particles of larger size, such as glass and ceramics, so as to obtain a mineral product meeting regulatory requirements for use as supplementary cementitious material or other construction applications. This problem is particularly acute for waste streams containing complex mixtures of glass, ceramics, and metals, where conventional methods such as grinding to sub-micron size, acid leaching, or simple density separation are insufficient or uneconomical for achieving the required purity.

[0031] The primary technical problem is to separate the heavy metal particles that are trapped in the jagged edges of glass particles, from the glass and mineral particles themselves so that they can be used as SCMs. Furthermore, once dislodged by techniques such as ultrasound, effectively separating these fine particles from the glass and minerals to produce a clean fraction is also a technical challenge. This is made more complex due to the presence of small metal particles like chopped wire fragments, painted metal chips, heavy metal swarf, and fine metallic dust, which also need to be removed. The concentration of these metallic contaminants is too low to economically use mainstream approaches like acid leaching for metal recovery. This is a white space the Applicants intend to cover by solving this technical problem.SUMMARY OF THE INVENTION

[0032] According to embodiments of the invention provided, a minerals processing system transforming the waste product of glass and minerals from car recycling into RGMs — a sustainable Supplementary Cementitious Material (SCM) for low-clinker cement production. By providing a new local source of SCMs, this process reduces reliance on conventional materials such as blast furnace slag and silica fume.

[0033] A key advantage of the processing system of the invention is its ability to mechanically remove regulated heavy metals from recycling waste streams, ensuring compliance with local regulatory limits for the use of RGMs, such as the Swiss VeVA regulatory requirements, for cement production. Unlike traditional methods, this system operates without the use of toxic chemicals (e.g., mineral acids, etc.) and requires minimal energy input, resulting in a low-C02footprint SCM. By converting waste into a valuable cement additive, this invention supports a circular economy, enhances local SCM supply chains, and contributes to the decarbonization of cement production.

[0034] The processing system employs a carefully controlled sequence of separation techniques implemented in multiple modules, including: a module for the sizing of input mineral feed material with crushing and screening, a module using air-based fluid dynamics to remove plastics and lightweight hydrocarbons, a module using magnetic separation to extract light and heavy metals, enabling further recovery of valuable metals like steel, copper and aluminium, a module using ultrasonic cavitation to liberate residual trace heavy metals from minerals, and a module using heavy media separation using high-density fluid media to isolate RGMs from any remaining heavy metals. Each module is tightly monitored with process control and feedback mechanisms to ensure high-purity separation and minimal crosscontamination. The solution is designed as a modular and scalable system, leveraging readily available industrial equipment for rapid deployment. The system further comprises a feeding system for each of the modules, that could optionally have a liquid or a dust removal system.

[0035] In other example of embodiments, the system comprises a particle screening module that waste minerals feed material that comprises at least about 80% by weight of mineral material such as crushed glass, ceramics, quartz, or silica. An air-based sorting module separates out plastics and lightweight hydrocarbons. A magnetics-based module separates and sorts out metals, mainly steel, copper and aluminium. An ultrasonic cavitation module facilitates the liberation of the fine metallic particles stuck to the mineral material. A heavy media separation module finally recovers the RGMs, separating it from the residual metals and plastics. TheRGMs thus produced are generally free of metals - heavy metals concentration below the regulated limits for use in cement making.

[0036] In one aspect, the invention provides a method for recovering minerals from waste feedstock, comprising:

[0037] a) reducing the particle size of the waste feedstock by crushing and screening to obtain crushed waste particles of a desired particle size, wherein the crushing and screening are performed iteratively as needed to achieve the desired particle size;

[0038] b) preparing a slurry of said crushed waste particles in a liquid media;

[0039] c) subjecting the slurry to ultrasonic cavitation treatment at a particle size of at least 100 microns to separate attached metals from said crushed waste particles and recovering mixed solids from the ultrasound-cavitated slurry;

[0040] d) subjecting the mixed solids obtained from step (c) to heavy media separation by immersing the mixed solids in a dense liquid medium to obtain an immersed solids-liquid mixture; and

[0041] e) recovering the mineral product from the solids-liquid mixture of step (d) after the separation of residual metals and plastics;

[0042] wherein the waste feedstock comprises mineral-containing waste selected from glass waste with metallic contaminants, ceramics waste, construction and demolition waste, end-of-life solar panels, incineration bottom ash, electronic scrap, or automotive shredder residue, and wherein the combination of ultrasonic cavitation and heavy media separation is configured to reduce the level of metallic contaminants in the recovered mineral fraction.

[0043] In another aspect, the invention provides for the use of the minerals recovered by the above method in the preparation of materials selected from the group consisting of: supplementary cementitious materials (SCMs) or raw meal corrective for cement or concrete production; aggregates or fillers in mortars; or raw materials for producing insulation materials such as glass wool.

[0044] In another aspect, the invention provides a system for recovering minerals from waste feedstock. The system comprises a modular arrangement of interconnected units, including: a crushing and screening module for reducing the particle size of the waste feedstock; a slurry preparation module for mixing the crushed particles with a liquid medium; an ultrasonic cavitation module equipped with an ultrasonic horn or transducer for subjecting the slurry to ultrasonic treatment at a particle size of at least 100 microns, thereby detaching metallic contaminants from the mineral surfaces; a heavy media separation module for immersing the treated solids in a dense liquid medium to separate high-density metallic particles from lightermineral fractions; and a recovery module for collecting the purified mineral product after removal of residual metals and plastics. The system may further comprise process control and feedback mechanisms for monitoring and adjusting the operation of each module and can be configured for batch or continuous operation. The modular design allows for rapid deployment and scale-up using readily available industrial equipment, and the system is suitable for pilot or industrial scale applications.

[0045] The above and still further features and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof.

[0046] BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 illustrates the overall system architecture of the invention and the associated sequence of the five steps detailed below.

[0048] Figure 2 shows the schematic of the Ultrasonic Cavitation step (section view and plan view). In this figure, the process chamber is denoted as ‘A’. This chamber is filled with a liquid media in which the feed particles are introduced from the top. While in free fall within the liquid media, these particles are subjected to ultrasonic cavitation using ultrasonic horns ‘B’. The number and orientation of these ultrasonic horns can be changed depending on the process conditions and feed parameters. In order to introduce more horns, their orientation ‘C’ can be changed as follows: 2 horns are 180 degrees apart, 3 horns are 120 degrees apart, 4 horns are 90 degrees apart, and so on. The output after cavitation is removed from the bottom of the cavitation tank using collection valves.

[0049] Figure 3 shows the schematic of the Heavy Media Separation step. This figure shows the section view of a dedicated tank where the feed is injected into the chamber from the left-hand side ‘A’ at an injection velocity. The four primary constituents of the input material are separated depending on their density - the highest density materials, the heavy metals, get collected in chamber ‘B’, the lighter metals get collected in chamber ‘O’, the recovered glass and minerals (RGMs) get collected in chamber ‘D’, and the lightest plastics float to the surface and get collected at point ‘E’. The chambers in the tank are separated with movable separators ‘F’ which can be moved depending on the operating parameters and heavy media liquid ‘G’ density.

[0050] DETAILED DESCRIPTION OF THE INVENTIONThe invention is an innovative upcycling system that converts industrial recycling waste into Recovered Glass Minerals (RGMs) — a sustainable additive for low-clinker cement production. The process of the invention provides a local, low-C02alternative to conventional additives such as blast furnace slag and silica fume. The processing system mechanically removes regulated heavy metals from recycling waste streams, ensuring compliance with regulatory standards for cement production. The process operates without toxic chemicals or high energy consumption, making it an environmentally friendly solution. It employs a multi-step separation process, including air-based fluid dynamics, magnetic separation, ultrasonic cavitation, and heavy media separation. These steps efficiently extract plastics, metals, and contaminants while isolating high-purity RGMs for cement production. Designed as a modular, scalable solution, the system leverages readily available industrial equipment for rapid deployment and commercialization. By transforming waste into a valuable cement additive, this process enhances circular economy practices, strengthens local supply chains for additives, and contributes to cement industry decarbonization.

[0051] The present invention relates to a method for recovering minerals from waste feedstock by employing a combination of crushing, ultrasonic cavitation, and heavy media separation techniques to remove contained heavy metal contaminants. The recovered glass and minerals (RGMs) can be utilized in various industrial applications, including cement production, mortar fillers, and insulation materials subject to meeting the regulatory thresholds or limits.

[0052] As used herein and in the appended claims, the following terms have the meanings set forth below, unless the context clearly indicates otherwise:

[0053] “Waste feedstock” refers to any mineral-containing waste material suitable for processing according to the invention, including but not limited to glass waste with metallic contaminants, ceramics waste, construction and demolition waste, end-of-life solar panels, incineration bottom ash, electronic scrap, and automotive shredder residue (ASR). The waste feedstock may contain a mixture of mineral, metallic, plastic, and other non-metallic components.

[0054] “Crushing and screening” refers to mechanical processes for reducing the size of waste feedstock particles and separating them into fractions based on particle size. “Iteratively” means that these steps may be repeated as needed to achieve the desired particle size distribution.

[0055] “Slurry” means a suspension of solid waste particles in a liquid medium, such as water, alcohols, esters, halogenated alkanes, ketones, or combinations thereof.“Ultrasonic cavitation treatment” refers to the application of high-frequency ultrasound waves (typically in the range of 10 kHz to 50 kHz) to a slurry, resulting in the formation and collapse of microscopic bubbles that generate localized high energy, thereby detaching metallic contaminants and other surface-bound impurities from mineral particles. The treatment may be performed in batch or continuous mode, and the “ultrasonic horn” or “transducer” refers to the device generating the ultrasound.

[0056] “Heavy media separation” means a density-based separation process in which solids are immersed in a dense liquid medium (e.g., lithium heteropolytungstate (LST) Fastfloat, methylene iodide, carbon tetrabromide, sodium meta-tungstate hydrate, cesium salts, rubidium salts, thallous salts, magnetite, or ferro-silicon) having a density of at least 2.3 g / cm3, to separate high-density metallic particles from lighter mineral and non-metallic fractions.

[0057] “Mineral product” or “recovered mineral fraction” refers to the purified mineral material obtained after the process, including but not limited to glass, ceramics, quartz, silica (SiO2), calcium carbonates, and trace amounts of rare earth metals, with a reduced content of metallic contaminants.

[0058] “Regulated heavy metals” or “metallic contaminants” refers to metals such as lead, cadmium, mercury, chromium, cobalt, nickel, copper, zinc, arsenic, tin, antimony, and others, whose concentrations are subject to regulatory limits for use in construction materials.

[0059] “Supplementary Cementitious Material (SCM)” means a mineral additive used in cement or concrete production to partially replace clinker, improve material properties, and reduce CO2emissions.

[0060] “System” or “machine” refers to an arrangement of interconnected modules or units configured to perform the steps of the method of the invention, including but not limited to crushing and screening, slurry preparation, ultrasonic cavitation, heavy media separation, and recovery of the mineral product. The system may further comprise modules for air-based sorting, magnetic or electrostatic separation, process control, and automated feeding or washing.

[0061] “Modular” means that the system is composed of distinct units or modules that can be assembled, reconfigured, or scaled according to processing needs.

[0062] “Batch” and “continuous” refer to modes of operation, where “batch” means processing discrete quantities of material in separate cycles, and “continuous” means ongoing processing of material streams.“Process control and feedback mechanisms” refers to sensors, controllers, and automated systems for monitoring and adjusting process parameters (e.g., flow rates, densities, power levels) to ensure consistent operation and product quality.

[0063] Unless otherwise indicated, all percentages, ratios, and amounts are by weight, and all process steps may be performed in any suitable order or combination, unless the context requires otherwise.

[0064] In particular, the invention provides a method for recovering minerals from waste feedstock, comprising:

[0065] a) reducing the particle size of the waste feedstock by crushing and screening to obtain crushed waste particles of a desired particle size, wherein the crushing and screening are performed iteratively as needed to achieve the desired particle size;

[0066] b) preparing a slurry of said crushed waste particles in a liquid media;

[0067] c) subjecting the slurry to ultrasonic cavitation treatment at a particle size of at least 100 microns to separate attached metals from said crushed waste particles and recovering mixed solids from the ultrasound-cavitated slurry;

[0068] d) subjecting the mixed solids obtained from step (c) to heavy media separation by immersing the mixed solids in a dense liquid medium to obtain an immersed solids-liquid mixture; and

[0069] e) recovering the mineral product from the solids-liquid mixture of step (d) after the separation of residual metals and plastics;

[0070] wherein the waste feedstock comprises mineral-containing waste selected from glass waste with metallic contaminants, ceramics waste, construction and demolition waste, end-of-life solar panels, incineration bottom ash, electronic scrap, or automotive shredder residue, and wherein the combination of ultrasonic cavitation and heavy media separation is configured to reduce the level of metallic contaminants in the recovered mineral fraction.

[0071] According to an embodiment of the invention, the method of the invention, further comprising processing the treated slurry through a sequential or iterative procedure combining ultrasonic cavitation treatment of step (c), heavy media separation of step (d), and crushing and / or screening of step (a), wherein the process parameters are optimized to maximize contaminant removal and mineral recovery yield.

[0072] According to another embodiment the method further comprising a chemical treatment step, wherein the mineral product of step (e) is leached with an acidic or basic chemical reagent or solvent for further purification.Advantageously, the waste feedstock is selected from automobile recycling waste, construction and demolition waste, end-of-life solar panels, or incineration bottom ash, or glass waste with metallic contaminants, ceramics waste, electronic scrap, or automotive shredder residue.

[0073] According to another embodiment, the waste particles are obtained by iteratively crushing and screening the waste feedstock to a particle size of between 0.1 mm and 5 mm.

[0074] Still according to another embodiment, the liquid media of step (b) is selected from the group consisting of alcohols, esters, halogenated alkanes, ketones, water, ora combination thereof.

[0075] Preferably, the ultrasonic cavitation treatment of step (c) is performed by applying ultrasound waves at a frequency range from 10 kHz to 50 kHz for 10 seconds to 10 minutes, and wherein the ultrasonic treatment is effective to detach metallic fines from the surface of mineral particles.

[0076] According to an embodiment of the invention, recovering the mixed solids from the ultrasonic cavitated slurry of step (c) is performed by centrifugation or filtration, followed by drying.

[0077] Preferably, the dense liquid medium of step (d) has a density of at least 2.3 g / cc, to achieve separation of high-density metallic particles from lighter non-metallic fractions.

[0078] More preferably, the dense liquid medium of step (d) is selected from the group consisting of methylene iodide, LST Fastfloat, carbon tetrabromide, sodium meta-tungstate hydrate, cesium salts, rubidium salts, or thallous salts, magnetite or ferro-silicon.

[0079] According to another embodiment, recovering the mineral product from the solids-liquid mixture of step (d) is performed by centrifugation or filtration, followed by drying.

[0080] In an embodiment of the invention, the method further comprising a step of selectively separating non-metallic impurities, including plastics and ceramics, priorto step (a) or between steps (a) and (b).

[0081] In particular, the minerals recovered include glass, ceramics, quartz, silica (SiO2), calcium carbonates, and trace amounts of rare earth metals, and wherein the recovered mineral fraction contains at most 1000 ppm of total metallic contaminants as measured by XRF or surface analysis.The invention further provides for the use of the minerals recovered by the above method in the preparation of materials selected from the group consisting of: supplementary cementitious materials (SCMs) or raw meal corrective for cement or concrete production; aggregates or fillers in mortars; or raw materials for producing insulation materials such as glass wool. In particular, the recovered minerals, due to their reduced content of metallic contaminants, are suitable for these applications and can be used to enhance the properties of cement, concrete, mortar, or insulation products. In a preferred embodiment, the raw materials for producing insulation materials include pre-treated silica and soda ash to enhance the thermal insulation properties of the final product.

[0082] Process Overview:

[0083] The method according to the invention begins with the preparation of waste feedstock by reducing its particle size through crushing and screening. The crushed particles are then dispersed in a liquid medium to form a slurry, which is subjected to ultrasonic cavitation treatment. This step facilitates the separation of attached metals from the waste particles. The recovered mixed solids undergo further separation using a heavy media technique, wherein a dense liquid medium separates high-density metallic particles from non-metallic fractions. The minerals are subsequently recovered by removing residual metals and plastics.

[0084] Step-by-Step Process Description:

[0085] Step (a): Crushing and Screening

[0086] The waste feedstock is initially processed through mechanical crushing to break down large waste materials into smaller particles using commercially available crushing equipment. Screening ensures that the crushed particles achieve a desired particle size, typically less than 5 mm. The dust generated during the crushing and screening process is removed to prevent the adverse effects in downstream steps or equipment fouling.

[0087] This step may produce fractions in different size ranges to ease operational control downstream (e.g., 100-1000 microns, 1-2 mm, 2-5 mm, or some other combination to be determined during the testing of the material and the associated process optimisation).

[0088] Step (b): Formation of Slurry

[0089] The screened waste particles are mixed with a liquid medium to create a slurry. The liquid medium may include alcohols, esters, halogenated alkanes, ketones, water, or a combination thereof. In this step, the particles need to be adequately wetted so all the surfaces are directlyinteracting with the liquid media. In case this is not achieved, the process performance is likely to be reduced.

[0090] Step (c): Ultrasonic Cavitation Treatment

[0091] Ultrasonic cavitation is a process that uses high-frequency ultrasound waves to create microscopic bubbles in a liquid medium. These bubbles rapidly expand and collapse, generating intense localized pressure and temperature. This phenomenon helps break down solid particles, remove adhered contaminants, and facilitate the separation of materials, making it useful in mineral recovery, cleaning, and extraction processes.

[0092] The slurry undergoes ultrasonic cavitation in a dedicated chamber or vessel, where ultrasound waves in the frequency range of 10 kHz to 50 kHz are applied for a duration ranging from 10 seconds to 10 minutes. This treatment effectively detaches heavy metal particles adhered to the jagged edges of crushed glass and minerals due to the energy released when the micro bubbles in the liquid media collapse near the surfaces of the solids.

[0093] The separation of minerals and metals from the treated slurry liquid is achieved through centrifugation or filtration, followed by drying.

[0094] Step (d): Heavy Media Separation

[0095] The mixed solids obtained from ultrasonic treatment step (c) are subjected to heavy media separation. In this step, the solids are immersed in a dense liquid medium with a density of at least 2.3 g / cc. Suitable dense media include methylene iodide, LST Fastfloat, carbon tetrabromide, sodium meta-tungstate hydrate, suspension of iron compounds such as magnetite and ferro-silicon, and various salts solutions. This technique enables the separation of high-density metallic particles from lighter non-metallic materials.

[0096] This step is preferably executed in a specially designed chamber or vessel of adequate size where the flows of the streams of the heavy media drive efficient separation of the solid minerals from the metals and any residual plastics. These flows are an interplay between the inlet velocities and the terminal velocities of particles. Experiments and associated process simulation show that the separation is quick but mineral particles must be guided well into the relevant outlet - separate outlets for the following: minerals, heavy metals, light metals, and plastics.

[0097] Step (e): Recovery of Glass and MineralsFollowing heavy media separation, the minerals are recovered through washing, followed by centrifugation or filtration, followed by drying. This step is key to return the heavy media back into the process and separate it out from the final products.

[0098] This process yields purified recovered glass and minerals (RGMs), while eliminating residual metals and plastics. The recovered minerals typically include glass, ceramics, quartz, silica (SiO2), calcium carbonates, and may also contain trace amounts of rare earth elements.

[0099] Optional Enhancements:

[0100] 1. Iterative Processing: The treated slurry can be processed iteratively using a combination of the above-mentioned steps of ultrasonic cavitation, heavy media separation, and additional crushing or screening to improve recovery efficiency.

[0101] 2. Chemical Treatment: The minerals may undergo further purification via chemical leaching using acidic or basic reagents or solvents. This may also include reacting the RGMs with a liquid or gas media containing carbon dioxide (CO2) and the CO2gets sequestered by becoming a part of the mineral material.

[0102] 3. Selective Separation: Non-metallic impurities such as plastics and ceramics can be selectively removed prior to or during mineral recovery.

[0103] 4. Metals Removal: Removing light and heavy metals from the input material before Step (a) using magnetic, Eddy Current, or electro-static separators.

[0104] Another object of the invention is to provide the use of the recovered minerals obtained by the method of the invention, in the preparation of materials selected from the groups comprising: SCMs or raw meal corrective for cement or concrete production; aggregates or fillers in mortars; or of raw material to produce insulation materials such as glass wool.

[0105] According to an embodiment of the invention, the raw material to produce insulation materials include pre-treated silica and soda ash to enhance the thermal insulation properties of the final product.

[0106] Applications of Recovered Glass and Minerals:

[0107] The recovered glass and minerals find utility in several industrial applications, including:1. Cement Production: Used as a feedstock for the production of low-clinker cement, as a corrective material in Raw Meal Preparation, or a process additive like an SCM, with the produced cement having comparable performance in areas of strength and durability.

[0108] 2. Aggregates and Fillers: Incorporated into mortars as aggregates to improve structural integrity while replacing natural materials.

[0109] 3. Insulation Materials: Processed into glass wool or other insulating products using standard glass extrusion processes.

[0110] By implementing the method of the invention, valuable minerals can be efficiently reclaimed from various waste sources, including automobile recycling waste, electronic scrap, construction and demolition waste, end-of-life solar panels, and incineration bottom ash. This process not only contributes to resource conservation but also minimizes environmental impact by reducing waste disposal in landfills.

[0111] According to another object of the invention, it is provided a system or machine for recovering minerals from waste feedstock, comprising:

[0112] a) means for reducing the particle size ofthe waste feedstock to obtain crushed waste particles of a desired particle size, wherein the means for reducing particle size comprises at least one of crushing means and screening means configured to operate iteratively as needed; b) means for preparing a slurry of the crushed waste particles in a liquid media; c) means for subjecting the slurry to ultrasonic cavitation treatment to separate attached metals from the crushed waste particles and recovering mixed solids from the ultrasound-cavitated slurry; d) means for subjecting the mixed solids to heavy media separation by immersing the mixed solids in a dense liquid medium to obtain an immersed solids-liquid mixture; and e) means for recovering a mineral product from the solids-liquid mixture after separation of residual metals and plastics.

[0113] Ideally, the system is modular and comprises a plurality of interconnected modules, each module configured to perform one or more ofthe steps (a) to (e).

[0114] Preferably, the plurality of modules are housed within a standalone unit, optionally configured to fit within 2 to 4 shipping containers or as a collection of standalone tanks with materials moving between them.Y1

[0115] The system or machine of the invention, further comprising:

[0116] - a particle screening module configured to receive waste mineral feed material comprising at least about 80% by weight of mineral material, such as crushed glass, ceramics, quartz, or silica;

[0117] - an air-based sorting module configured to separate plastics and lightweight hydrocarbons from the waste feedstock;

[0118] - magnetics or electrostatics -based module configured to separate and sort metals, including steel, copper, and aluminium;

[0119] - an ultrasonic cavitation module comprising an ultrasonic horn or transducer, configured to subject the slurry to ultrasonic cavitation at a particle size of at least 100 microns, at a frequency between 10 kHz and 50 kHz and a power up to 40 W as ultrasound, in batch or continuous mode, to detach metallic contaminants from the surface of the mineral particles;

[0120] - a heavy media separation module configured to recover regulated heavy metals (RGMs) from the residual metals and plastics, comprising a separation tank operated with a dense liquid medium (e.g., LST Fastfloat) at a density of at least 2.3 g / cm3, with recirculation and filtration systems for the dense medium, as exemplified by the SepX prototype.

[0121] According to an embodiment, the system further comprising process control and feedback mechanisms configured to monitor and adjust the operation of each module to ensure high-purity separation and minimal cross-contamination.

[0122] According to another embodiment the system further comprising a feeding system for each module, optionally including a liquid or dust removal system.

[0123] According to yet another embodiment, the system is configured to mechanically remove regulated heavy metals (RGMs) from recycling waste streams, ensuring compliance with local regulatory limits for the use of RGMs in cement production.

[0124] Preferably, the system of the invention operates without the use of toxic chemicals and requires minimal energy input, resulting in a low-C02footprint.In particular, the mineral product recovered by the system of the invention is suitable for use as a supplementary cementitious material (SCM) in cement production.

[0125] More preferably, the system is scalable and configurable for pilot or industrial scale operation and can be rapidly deployed using readily available industrial equipment.

[0126] In particular, pilot-scale implementations of the system have demonstrated the feasibility of continuous operation for both ultrasonic cavitation and heavy media separation modules. For example, the ultrasonic cavitation module may comprise a vertical or horizontal sonication chamber equipped with an ultrasonic horn operating at up to 40 W, as ultrasound and frequencies between 10 kHz and 50 kHz, as realized in the Ultra-X prototype. The feed material is introduced via a screw feeder and passes through the sonication zone, where geometric flow retarders or recirculation features can be used to increase particle residence time and ensure effective cleaning of mineral surfaces. The system can be operated in batch or continuous mode, with process parameters (such as power density, sonication time, and feed rate) optimized based on the nature of the waste feedstock.

[0127] The heavy media separation module may comprise a separation tank (as in the SepX prototype) with a working volume of 10 liters or more, operated with a dense liquid medium such as lithium heteropolytungstate (LST Fastfloat) at a density of at least 2.3 g / cm3. The feed material is introduced into the tank via a controlled inlet, and flow-conditioning geometries are used to promote uniform dispersion and minimize particle clustering. The system includes recirculation and filtration units for the dense medium, and the separated fractions (minerals, metals, plastics) are collected via dedicated outlets. The design can be adapted for larger throughputs by increasing tank size, optimizing inlet geometry, or implementing automated feeding and washing systems.

[0128] Process control and feedback mechanisms, such as flow sensors, density meters, and automated washing units, can be integrated to monitor and adjust operating parameters in real time, ensuring consistent product quality and efficient recovery of the dense medium. The modular architecture allows for rapid scale-up and customization to different waste streams or processing capacities. The system components can be housed in standalone units or shipping containers for ease of transport and deployment at industrial sites.

[0129] These pilot-scale demonstrations confirm that the system is technically and economically viable for industrial application, enabling the recovery of high-purity mineral fractions from complex waste streams and supporting the transition to a circular economy in the construction materials sector.The modular and scalable design of the system allows for rapid adaptation to different processing capacities and waste types. Additional modules, such as advanced process control, automated feeding, or specialized separation units, can be integrated as needed to meet specific industrial requirements or to process new types of mineral-containing waste.

[0130] The invention is not limited to the specific embodiments described herein. Other types of mineral-containing waste, alternative dense media (such as sodium polytungstate or other high-density salt solutions or mineral suspensions), or different ultrasonic configurations (e.g., multiple horns, variable frequencies) may be used without departing from the scope of the invention. The modular architecture allows for the integration of additional modules, such as advanced sensors, automated washing units, or real-time contaminant monitoring systems, to further enhance process performance and adaptability.

[0131] The system is designed for safe, reliable, and low-maintenance operation in industrial environments. All modules are equipped with access points for cleaning and inspection, and the process control and feedback mechanisms enable automated monitoring of key parameters, reducing the need for manual intervention. The use of non-toxic, recyclable process media further enhances operational safety and environmental compatibility.

[0132] The process enables the production of mineral fractions that meet or approach stringent regulatory limits for heavy metals and other contaminants, such as those set by the Swiss VeVA and European ADWO standards. The flexibility of the process allows for further optimization to ensure compliance with evolving regulatory requirements in different jurisdictions.

[0133] The invention supports the transition to a circular economy by enabling the recovery and reuse of valuable mineral resources from waste streams that would otherwise be landfilled. By reducing the need for virgin raw materials and minimizing waste disposal, the process contributes to significant reductions in CO2emissions and environmental impact, in line with global sustainability goals for the construction industry.

[0134] Technical effects and advantages

[0135] The invention provides several technical effects and advantages over the prior art:

[0136] The combination of ultrasonic cavitation and heavy media separation enables the efficient detachment and removal of small or fine metallic contaminants from mineral particles, including those trapped in surface irregularities or adhered as dust, whichare not effectively removed by conventional grinding, acid leaching, or density separation alone.

[0137] - The process achieves a significant reduction in the concentration of regulated heavy metals (such as Pb, Cu, Zn, Sb, etc.), allowing the recovered mineral fraction to meet or approach stringent regulatory limits for use in cement and construction materials.

[0138] - The method operates without the use of toxic chemicals and with minimal energy input, resulting in a low environmental footprint and improved safety for operators.

[0139] - The modular and scalable system design allows for rapid adaptation to different waste streams, processing capacities, and industrial requirements.

[0140] - The process is robust, repeatable, and suitable for continuous industrial operation, as demonstrated by pilot-scale implementations.

[0141] - The invention supports circular economy objectives by transforming waste into valuable resources, reducing landfill disposal, and decreasing the need for virgin raw materials in the construction industry.

[0142] - The technical effects achieved by the invention are not suggested or taught by the prior art, which does not disclose or motivate the specific combination of ultrasonic cavitation at a particle size of at least 100 microns with heavy media separation for the recovery of high-purity mineral fractions from complex waste streams.

[0143] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications without departing from the spirit or essential characteristics thereof. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations or any two or more of said steps or features. The present disclosure is therefore to be considered as in all aspects illustrated and not restrictive, the scope of the invention being indicated by the appended Claims, and all changes which come within the meaning and range of equivalency are intended to be embraced therein.

[0144] The foregoing description will be more fully understood with reference to the following Examples. Such Examples, are, however, exemplary of methods of practising the present invention and are not intended to limit the scope of the invention. The following examples illustrate the implementation and advantages of the invention across a range of wastefeedstocks, process configurations, and operating conditions. The data demonstrate the technical feasibility, process optimization, and industrial scalability of the method and system as claimed.

[0145] Examples:

[0146] Example 1:

[0147] Input Material: The process uses the mineral fraction from car recycling waste, left after removing most ferrous and non-ferrous metals. This fraction does not meet Swiss VeVA requirements for cement making. This material was treated according to the method of the invention.

[0148] Series 1 tests: Tested Ultrasonic Cavitation for separating metallic and mineral particles. Results showed good separation of fine and large particles, with reduced heavy metals (Pb, Co, Cu, Zn, Sb), though still above VeVA limits. Some fine copper wires and metal chunks remained.

[0149] Series 2 tests: Evaluated Heavy Media Separation for removing metallic pieces. Without sonication, ~12% of the heavy metallic fraction was removed, improving compliance with VeVA limits.

[0150] Series 3-5 tests: Combined Ultrasonic Cavitation and Heavy Media Separation applying the learnings from the Series 1 and 2 test work and iteratively refined the overall process to improve compliance with VeVA limits.

[0151] The results of these tests in comparison to the input concentrations and the corresponding VeVA limits are presented in table 1 below.

[0152] Element Input Series 1 Series 2 Series 3 Series 4 Series 5 Limit Sb 380 339 175 204 141 176 30 As 60 60 36 56 40 47 30 Pb 13000 4484 568 416 199 295 500 Cd 37 na 9 9 3.2 1.9 5 Cr 2400 606 178 181 130 115 1000 Co na 1793 135 115 105 120 250 Cu 25000 2524 234 169 260 69 500 Ni 1400 4699 322 158 222 129 500

[0153]

[0154] Hg 0.3 6 0.4 0.38 0.06 0.17 1 Tl 0.1 na 1.5 0.31 2.3 0.17 3 Zn 44000 16950 5632 4226 1993 1900 2000 Sn 1700 561 68 88 55 76 100

[0155]

[0156] Table 1: Elemental concentrations in mg / kg

[0157] Conclusion: The invention proves to be a promising innovation for effectively reducing heavy metal contamination and advancing compliance with standards like the Swiss VeVA. While some residual metals remain, the approach significantly improves material purity, offering a valuable step toward sustainable recycling solutions.

[0158] Example 2: Pilot-Scale ultrasonic cleaning and heavy media separation of minerals recovered from Automotive Shredder Residue (ASRm)

[0159] A batch of 713 grams of minerals from automotive shredder residue (ASRm), containing a mixture of mineral, metallic, and plastic fractions, was processed using a two-step method. First, the ASRm was subjected to ultrasonic cavitation treatment in a pilot-scale “Ultra-X” system. The sonication was performed in continuous mode, with the ASRm fed at a rate of 10.8 kg / h and the ultrasonic horn operated at 40 W, immersed 2 cm below the liquid surface. The average residence time for each particle in the sonication zone was approximately 3 seconds. The ASRm was pre-sieved to a particle size range of 0.3-1 mm to ensure uniform treatment.

[0160] Following sonication, the material was immediately transferred to a continuous heavy media separation (HMS) unit (“SepX”), where lithium heteropolytungstate (LST) was used as the dense medium at a density of 2.6 g / cm3and a flow rate of 2.7 L / min. The separation process allowed for the partitioning of the feed into a mineral-rich (glass / ceramic) fraction and a heavy fraction containing metals and dense plastics.

[0161] The results are summarized in Table 2 below:

[0162] Table 2: Separation results for pilot-scale ASR processing

[0163] Fraction Mass (g) Yield (%) Main Observations

[0164] Composition

[0165]

[0166] Input ASRm 713 100 Mixed -

[0167] Mineral (glass) 449 63 Glass, ceramics Clean, low visible contamination

[0168] Heavy (metals) 264 37 Metals, dense Blue coloration plastics (metal presence)

[0169]

[0170] Table 2

[0171] Microscopic examination of the mineral fraction revealed a significant reduction in surface metallic fines and plastic contaminants compared to untreated ASRm. The process was robust and repeatable, with minimal loss of LST after washing and recovery steps.

[0172] Technical conclusion:

[0173] This example demonstrates that the combination of ultrasonic cavitation and heavy media separation enables efficient and selective recovery of a clean mineral fraction from complex, contaminated ASRm. The process is robust, scalable, and provides a mineral output suitable for use as supplementary cementitious material (SCM) after further optimization. The observed effectiveness is not achievable by either step alone, highlighting the synergy and unexpected technical effect of the combined process.

[0174] Example 3: Optimization of ultrasonic parameters for surface cleaning

[0175] A series of laboratory-scale experiments were conducted to optimize the ultrasonic cleaning step for mineral waste. ASRm samples were treated at varying sonication power densities and durations. The cleaning effect was quantified by image analysis (mean gray value) and microscopic inspection, providing both qualitative and quantitative assessment of contaminant removal.

[0176] In these experiments, sonication was performed in batch mode with sample masses ranging from 0.04 to 0.75 g. Power densities of 0.37 to 0.67 W / mL were applied, and sonication times varied from 30 to 480 seconds. The cleaning effect was assessed by measuring the increase in mean gray value of the suspension (indicating removal of dark, contaminant particles) and by analyzing the particle size distribution.The results are presented in Table 3:

[0177] Table 3: Effect of sonication parameters on cleaning efficiency

[0178] Power Density Sonication Time (s) Mean Gray Value Observed Effect (W / mL) Increase

[0179] 0.37 120 +42 Moderate cleaning

[0180] 0.67 120 +49 Strong cleaning,

[0181] more fines

[0182] 0.67 240 +70 Maximum cleaning,

[0183] plateau

[0184]

[0185] Table 3

[0186] The data show that most of the cleaning effect occurs within the first 2-4 minutes of sonication, with higher power densities accelerating the process. Microscopic images confirmed that sonicated particles exhibited smoother surfaces and fewer attached contaminants. The particle size distribution shifted toward smaller sizes, indicating both surface cleaning and mild abrasion.

[0187] Technical conclusion:

[0188] These results demonstrate that the ultrasonic cleaning step can be tuned for optimal contaminant removal by adjusting power density and sonication time. The process is effective, rapid, and adaptable to different waste streams. The ability to achieve significant cleaning in a short time frame is advantageous for industrial applications and supports the technical feasibility of the claimed process.

[0189] Example 4: Demonstration of synergy between ultrasonic treatment and heavy media separation

[0190] To illustrate the synergy between ultrasonic treatment and heavy media separation, comparative experiments were performed. In one set, ASRm samples were processed directlyin the HMS unit without ultrasonic pre-treatment. In the other set, samples were first subjected to ultrasonic cavitation (as described in Example 2) before HMS.

[0191] The purity of the recovered mineral fraction and the efficiency of contaminant removal were compared. The results are summarized in Table 4:

[0192] Table 4: Comparison of Mineral Fraction Purity

[0193] Treatment Mineral Yield (%) Surface Cleanliness Residual (Qualitative) Contaminants (Visual)

[0194] HMS only 50-55 Moderate Visible metallic fines

[0195] Ultrasonic + HMS 60-65 High Minimal

[0196]

[0197] Table 4

[0198] Without ultrasonic pre-treatment, metallic fines and surface contaminants remained attached to the mineral particles, reducing the effectiveness of the density-based separation. When ultrasonic treatment was applied prior to HMS, the mineral fraction was visibly cleaner, with smoother surfaces and a higher yield of usable material. This improvement was confirmed by both visual and microscopic analysis.

[0199] Technical conclusion:

[0200] The combination of ultrasonic cavitation and heavy media separation achieves a level of cleaning and separation not attainable by either method alone. This synergy results in an unexpected technical effect, enabling the efficient recovery of clean mineral fractions from contaminated waste streams. Such an effect is not suggested or taught in prior art.

[0201] Example 5: Process robustness and industrial feasibility

[0202] The pilot-scale system was operated continuously for several hours, processing both ASRm and glass waste. The system demonstrated stable operation, effective contaminant removal, and efficient recovery of the dense medium. The process was tested with different feedstocks and maintained high mineral yields and low losses of LST.Table 5: Summary of pilot-scale operation

[0203] Feedstock Type Throughput Mineral Yield (%) LST Loss Operational (kg / h) (mL / kg) Issues

[0204] ASRm 10.8 63 0.3 Minor inlet clogging

[0205] Glass waste 10 65 0.3 None

[0206]

[0207] Table 5

[0208] The process was robust and adaptable to different mineral waste streams. LST losses were minimal and manageable with proper washing and recovery procedures. The system can be further optimized for higher throughput and improved contaminant removal.

[0209] Technical conclusion:

[0210] This example demonstrates the industrial feasibility and robustness of the claimed process. The system can be operated continuously with high yields and minimal losses and is adaptable to various types of mineral-containing waste. These results support the scalability and practical applicability of the invention.

[0211] General discussion

[0212] The above examples collectively demonstrate the technical feasibility, robustness, and industrial scalability of the claimed process. The synergy between ultrasonic cavitation and heavy media separation provides an unexpected and advantageous effect, enabling the recovery of clean mineral fractions from complex, contaminated waste streams. The process parameters can be optimized for different feedstocks and regulatory requirements, and the data supports broad claims covering various mineral-containing wastes, not limited to automotive shredder residue.

[0213] The process is designed to maximize the recovery and recycling of the dense liquid medium (e.g., LST Fastfloat). Pilot-scale tests have demonstrated that over 98% of the dense medium can be recovered and reused in subsequent cycles, with losses as low as 0.3 mL per kilogram of processed waste. This high recovery rate ensures the economic and environmental sustainability of the process, minimizing both operating costs and environmental impact.The process operates without toxic chemicals and is designed for safe, reliable, and low-maintenance operation in industrial environments.

[0214] The invention enables the production of mineral fractions that meet or approach regulatory limits for use in cement and construction materials, thereby supporting circular economy objectives and reducing the environmental impact of waste disposal.REFERENCES

[0215] 1Cement is a big problem for the environment. Here's how to make it more sustainable Sep 13, 2024 [link] [https: / / www.weforum.org / stories / 2024 / 09 / cement-production-sustainable-concrete-co2-emissions / #:~:text=Global%20cement%20manufacturing%20produced%201.6,to%20achievi ng%20global%20climate%20targets.]

[0216] 2The role of CEMENT in the 2050 LOW CARBON ECONOMY, The European Cement Association [link]

[0217] [https : / / cembureau. eu / media / cpvoin5t / cembureau_2050roadmap_lowcarboneconomy_2013-09-01.pdf]

[0218] 3Decarbonizing Cement: Technology assessment and policy relevant evidence for the decarbonization of the Swiss cement industry Final Report 22.06.2022 for Bundesamt fur Energie, Bundesamt fur Umwelt [link]

[0219] [https: / / www.ar amis. admin.ch / Default?DocumentID=69298&Load=true]

[0220] 4Optimizing supplementary cementitious material replacement to minimize the environmental impacts of concrete. Knight et al. Department of Civil and Environmental Engineering, University of California, Davis, USA [link] [https: / / www.sciencedirect.com / science / article / pii / S0958946523001233]

[0221] 5CEMBUREAU Key Facts & Figures, Published in June 2024 [link] [https: / / cembureau.eu / media / 00ejjclj / key-facts-figures-pubhcation-june-2024.pdfl

[0222] 6Clinker Substitution In The Cement Industry, CEMBUREAU, 5 March 2024 [link] [https : / / cembureau. eu / media / qeohlghe / 240305 -cembureau-position-faq-on-clinker-substitution.pdf]

[0223] 7Cemsuisse Interview: Nick Traber uber die Nutzung und Erschliessung von Abbaugebieten [link] [https: / / www.cernsuisse.ch / app / uploads / 2020 / 02 / Interview_Nick_Traber-l.pdf]8Roadmap to Carbon Neutrality: A more sustainable world is Shaped by Concrete, PUBLISHED OCTOBER 2021 [link] [https: / / www.cement.org / wp-content / uploads / 2024 / 05 / Roadmap_Jan2024.pdf|

[0224] 9Ordinance on the Avoidance and the Disposal of Waste (Waste Ordinance, ADWO) of 4 December 2015 (Status as of 1 January 2025) [link]

[0225] [https: / / www.fedlex.admin.ch / eli / cc / 2015 / 891 / en]

Claims

CLAIMS1. A method for recovering minerals from waste feedstock, comprising:a) reducing the particle size of the waste feedstock by crushing and screening to obtain crushed waste particles of a desired particle size, wherein the crushing and screening are performed iteratively as needed to achieve the desired particle size;b) preparing a slurry of said crushed waste particles in a liquid media;c) subjecting the slurry to ultrasonic cavitation treatment at a particle size of at least 100 microns to separate attached metals from said crushed waste particles and recovering mixed solids from the ultrasound-cavitated slurry;d) subjecting the mixed solids obtained from step (c) to heavy media separation by immersing the mixed solids in a dense liquid medium to obtain an immersed solids-liquid mixture; ande) recovering the mineral product from the solids-liquid mixture of step (d) after the separation of residual metals and plastics;wherein the waste feedstock comprises mineral-containing waste selected from glass waste with metallic contaminants, ceramics waste, construction and demolition waste, end-of-life solar panels, incineration bottom ash, electronic scrap, or automotive shredder residue and wherein the combination of ultrasonic cavitation and heavy media separation is configured to reduce the level of metallic contaminants in the recovered mineral fraction.

2. The method of claim 1 , further comprising processing the treated slurry through a sequential or iterative procedure combining ultrasonic cavitation treatment of step (c), heavy media separation of step (d), and crushing and / or screening of step (a), wherein the process parameters are optimized to maximize contaminant removal and mineral recovery yield.

3. The method of claim 1 or 2, further comprising a chemical treatment step, wherein the mineral product of step (e) is leached with an acidic or basic chemical reagent or solvent for further purification.

4. The method according to any of claims 1-3, wherein the waste particles are obtained by iteratively crushing and screening the waste feedstock to a particle size of between 0.1 mm and 5 mm.

5. The method according to any of claims 1-4, wherein the liquid media of step (b) is selected from the group consisting of alcohols, esters, halogenated alkanes, ketones, water, or a combination thereof.

6. The method according to any of claims 1-5, wherein the ultrasonic cavitation treatment of step (c) is performed by applying ultrasound waves at a frequency range from 10 kHz to 50 kHz for 10 seconds to 10 minutes, and wherein the ultrasonic treatment is effective to detach metallic fines from the surface of mineral particles.

7. The method according to any of claims 1-6, wherein recovering the mixed solids from the ultrasonic cavitated slurry of step (c) is performed by centrifugation or filtration, followed by drying.

8. The method according to any of claims 1-7, wherein the dense liquid medium of step (d) has a density of at least 2.3 g / cc, to achieve separation of high-density metallic particles from lighter non-metallic fractions.

9. The method according to any of claims 1-8, wherein the dense liquid medium of step (d) is selected from the group consisting of methylene iodide, LST Fastfloat, carbon tetrabromide, sodium meta-tungstate hydrate, cesium salts, rubidium salts, or thallous salts, magnetite orferro-silicon.

10. The method according to any of claims 1 -9, wherein recovering the mineral product from the solids-liquid mixture of step (d) is performed by centrifugation or filtration, followed by drying.

11. The method according to any of claims 1-10, further comprising a step of selectively separating non-metallic impurities, including plastics and ceramics, prior to step (a) or between steps (a) and (b).

12. The method according to any of claims 1-11, wherein the minerals recovered include glass, ceramics, quartz, silica (SiO2), calcium carbonates, and trace amounts of rare earth metals, and wherein the recovered mineral fraction contains at most 1000 ppm of total metallic contaminants as measured by XRF or surface analysis.

13. Use of the minerals recovered by the method according to any of claims 1-12, in the preparation of materials selected from the group consisting of: supplementarycementitious materials (SCMs) or raw meal corrective for cement or concrete production; aggregates or fillers in mortars; or raw materials for producing insulation materials such as glass wool, wherein the recovered minerals are suitable for such uses due to their improved purity and reduced contaminant content.

14. The use according to claim 13, wherein the raw materials for producing insulation materials include pre-treated silica and soda ash to enhance the thermal insulation properties of the final product.

15. The method or use according to any preceding claim, wherein the process is implemented at pilot or industrial scale and demonstrates robust operation with minimal loss of dense medium and consistent mineral recovery yields.

16. A system for recovering minerals from waste feedstock, comprising:- a crushing and screening module configured to reduce the particle size of the waste feedstock and to obtain crushed waste particles of a desired particle size, wherein the crushing and screening are performed iteratively as needed;- a slurry preparation module configured to mix the crushed waste particles with a liquid medium to form a slurry;- an ultrasonic cavitation module comprising an ultrasonic horn or transducer configured to subject the slurry to ultrasonic cavitation treatment at a particle size of at least 100 microns, to detach metallic contaminants from the surface of the mineral particles;- a heavy media separation module configured to immerse the mixed solids obtained from the ultrasonic cavitation module in a dense liquid medium to separate high-density metallic particles from lighter non-metallic fractions;- a recovery module configured to recover the mineral product from the solids- liquid mixture after separation of residual metals and plastics;wherein the system is modular and scalable, and optionally comprises process control and feedback mechanisms for monitoring and adjusting the operation of each module.

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