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WO-2026090648-A1 - THERMAL TREATMENT OF A MATERIAL COMPRISING A MINERAL

WO2026090648A1WO 2026090648 A1WO2026090648 A1WO 2026090648A1WO-2026090648-A1

Abstract

The present disclosure relates to a method of treating a material comprising a mineral, which comprises subjecting the material to radiant heating, for example a high flux and rapid radiant heating. In a particular form, the mineral is a hydrous mineral.

Inventors

  • CHINNICI, Alfonso
  • Saw, Woei Lean
  • LEWIS, Elliott William
  • COOK, Nigel J.
  • NATHAN, GRAHAM JEROLD

Assignees

  • Adelaide university

Dates

Publication Date
20260507
Application Date
20241031

Claims (20)

  1. 1. A method of treating a material comprising a mineral, which comprises subjecting the material to radiant heating.
  2. 2. The method according to claim 1, wherein the mineral is a hydrous mineral and the material is a material comprising a hydrous mineral.
  3. 3. The method according to either claim 1 or claim 2, wherein the material comprising a mineral is one or more selected from the group consisting of the mineral, ores comprising the mineral, rocks comprising the mineral, and soils comprising the mineral.
  4. 4. The method according to any one of claims 1 to 3, wherein the radiant heating is a pre-treatment prior to a downstream process.
  5. 5. The method according to claim 4, wherein the downstream process is selected from the group consisting of a comminution circuit, a dissolution process, and a carbonation process.
  6. 6. The method according to any one of claims 1 to 5, wherein the radiant heating is a rapid and uniform radiant heating.
  7. 7. The method according to any one of claims 1 to 6, wherein the radiant heating is conducted within a flameless environment.
  8. 8. The method according to any one of claims 1 to 7, wherein the mineral is a hydrous mineral and the hydrous mineral is one or more selected from the group consisting of goethite (FeO(OH)); (hydrous) hematite (for example, having a formula of 2Fe2O3-H2O); (hydrous) forsterite (for example, having a formula of Mg2 x SiO4H2x); antigorite (an idealised formula thereof: Mg3Si2Os(OH)4); lizardite (an idealised formula thereof: Mg3Si2Os(OH)4); chrysotile (an idealised formula thereof: Mg3Si2Os(OH)4); muscovite (KA12(AlSi3Ow)(OH)2); biotite (K(Mg,Fe)3AlSi3Ow(OH)2); bischofite (MgCF-hJLO); epsomite (MgSCL^FLO); gypsum (CaSC>4-2H2O); brucite (Mg(0H)2); (hydrous) aragonite; (hydrous) spodumene (for example, having a formula of 2[LiAlSi2C>62H2O]); (hydrous) magnesite (for example, having a formula of 3MgC0s- Mg(0H)2- 3H2O or MgCChAtLO); gibbsite (Al(0H)3); boehmite (A10(0H)); diaspore (A10(0H)); bay erite (Al(0H)3); doyleite (Al(0H)3); nordstrandite (Al(0H)3); kaolinite (A12Si205(0H)4); epidote (Ca2(Fe,Al)3(SiO4)3(OH)); and malachite (Cu2CO3(OH)2).
  9. 9. The method according to any one of claims 1 to 8, wherein the radiant heating has a uniform heating flux at the point source in the range of about 0.3 MW/m 2 to about 3 MW/m 2 .
  10. 10. The method according to any one of claims 1 to 9, wherein the radiant heating is carried out by means of a burner, for example a flat burner, such as a flat porous burner.
  11. 11. The method according to any one of claims 1 to 10, wherein the material is radiantly heated to a temperature in the range of about 300 °C to about 1200 °C.
  12. 12. The method according to any one of claims 1 to 11, wherein the radiant heating is carried out at a heating rate of about 5 °C/s to about 1000 °C/s, for example about 10 °C/s to about 1000 °C/s.
  13. 13. The method according to any one of claims 1 to 12, wherein the total exposure time for the material to be subjected to radiant heating is no more than about 30 minutes.
  14. 14. The method according to any one of claims 1 to 13, wherein the radiant heating is carried out at a distance between a radiant heating surface and the material to be heated that is between 5% and 25% of the width of a supporting surface (such as a conveying belt).
  15. 15. The method according to any one of claims 1 to 14, wherein, in conducting the radiant heating, particles of the material comprising a mineral are distributed over a supporting surface at a thickness of about 1 to 10 times the largest particle size of the material to be treated, for example, about 2 to 10 times, about 3 to 10 times, or about 5 to 10 times the largest particle size of the material to be treated.
  16. 16. The method according to any one of claims 1 to 15, wherein the material subjected to the radiant heating is in the form of particles and the particles of the material have an average size of about 1 pm to about 50,000 pm, for example about 1 pm to about 20,000 pm, or about 1 pm to about 10,000 pm.
  17. 17. The method according to any one of claims 1 to 16, wherein the material is one or more selected from the group consisting of a lizardite containing material, a goethite containing material, a hematite containing material, and a magnesite containing material.
  18. 18. A product obtained or obtainable by the method of according to any one of the preceding claims.
  19. 19. Use of radiant heating in inducing a physical change and/or a chemical change to a material comprising a mineral compared to the one without being subjected to the radiant heating; and/or in inducing a structural change and/or a compositional change to a material comprising a mineral compared to the one without being subjected to the radiant heating
  20. 20. Use of radiant heating in lowering the activation energy of calcination reaction of a mineral comprised by a material; increasing the specific surface area of a mineral comprised by a material; destabilising and removing chemically bound hydroxy groups or water molecules comprised by a mineral of a material; reducing the specific grinding energy required for a subsequent reduction of particle size of a material comprising a mineral; allowing different minerals contained by a material to expand at different rates when being rapidly heated and to be readily separated afterwards; adjusting and/or optimising the particle distribution of a material comprising a mineral after the radiant heating; upgrading a material comprising a mineral; and/or producing a calcined product or a beneficiated product from a material comprising a mineral.

Description

THERMAL TREATMENT OF A MATERIAL COMPRISING A MINERAL TECHNICAL FIELD [0001] The present disclosure relates generally to a method for treating a material comprising a mineral and uses thereof. In a specific form, the present disclosure relates to a method of treating a material comprising a hydrous mineral and uses thereof. BACKGROUND [0002] Reserves of high-grade (Fe > 60 wt%, minor impurities) iron ores are limited and those of grade sufficiently high for processing via the Direct-Reduced-Iron (DRI) to Electric Arc Furnace (EAF), typically classified as DR-Grade (Fe>68%), are even more limited. Lower-grade (for example, Fe < 55 wt% or significant impurities) iron ores are relatively plentiful, although they are presently not utilised effectively due to the cost of processing. One reason for this is that raw high gangue (i.e., impurities such as SiOz and AI2O3) ores are not compatible with current refinement processes, with the cost of processing increasing significantly with increasing gangue content [1]. Therefore, they must be beneficiated through pre-treatments before processing. New and improved technologies are required to treat available low- grade ore while making efficient use of energy and water as well as generating low carbon emissions. One potential method of improving the quality of iron ore is to heat it to >300 °C. [0003] Typically, industrial scale ore thermal treatment utilises furnaces, kilns, or fluidised beds for the purpose of heating. [0004] Furnaces and kilns are well established technologies that can handle a wide range of input ore sizes. However, they are typically energy intensive systems with limited capacity, long roasting times, relatively low throughput, and are prone to sticking or ring formation [2] . Comparatively, suspensionbased devices including fluidised bed and flash for pre-treatment are flexible in design, with a suspension roasting furnace being capable of providing a high capacity at low to moderate temperatures (e.g., 450 °C to 800 °C) with a relatively low energy consumption and absence of moving parts. These systems can provide rapid heating in the range of 100 °C/s to 1000 °C/s, depending on initial particle size. However, the effect of this change in heating rate on the material beneficiation has not been previously assessed. The primary drawbacks of these systems are that they require a dedicated large plant and for the feed to be pre-ground to <1 mm (typically in the range 10 pm to 200 pm for flash, and up to 500 pm for fluidised bed), which is an energy intensive process. Additionally, fluidised bed reactors have relatively poor control of the particle residence time, heating rate, or the temperature profile during heating [2], often resulting in undercooking/overcooking of the processed ore, while flash systems are at a much earlier stage of development for processing of iron ore. [0005] Another alternative heat treatment to provide relatively high heating rates of 10 °C/s to 100 °C/s (greater than for typical furnaces) is to use microwaves. The advantages of microwave heating are that it is non-intrusive, material selective (leading to thermal stresses from different expansions), and under certain conditions can heat the material volumetrically instead of just the surface as for typical heat transfer processes [24] . The microwave absorption of the phases within a material typically differs, leading to differences in the heating rates and therefore also thermal expansion. For example, goethite and hematite strongly absorb microwaves while quartz does not. This leads to cracks forming on grain boundaries [25], which allows greater liberation of iron during later processing. Additionally, the energy required to reach the same material temperature is much lower than that of a typical furnace, as shown in pilot-scale applications [26]. Extended heating periods have also been shown to heat the material in excess of 900 °C, and the process can be completed within reducing environments to promote the transition to magnetite [27]. However, micro wave equipment at the scale required for the pre-treatment of a mineral or an ore comprising a mineral requires highly specialised equipment that is still at an early stage of development. Parameters that still need to be addressed before these processes can be made commercial include how to address the variations in local microwave density and particle composition, together with limitations in the scale of the microwave technology and cost. Hence other methods of high flux heating are still needed. [0006] Mineral carbonation is an alternative and emerging approach for storing CO2, either from concentrated streams (e.g., flue gas) or from atmospheric air, and may provide an alternative to the better- known form of storage in stable geological reservoirs [3] . Mineral carbonation is a process whereby CO2 is sequestered in magnesium (Mg)- or calcium (Ca)-rich minerals [4], which are abundant in the Earth’s crust and comm