KR-20260066113-A - pellets

Abstract

A method for manufacturing pellets comprising: providing a particulate substrate selected from metal ore, metal ore-containing waste, metal fines, iron residue, iron powder, mineral waste, carbonaceous material, arc furnace waste, or a combination thereof; mixing the particulate substrate with a binder formulation comprising at least one binding material to form a substrate mixture; applying pressure to the substrate mixture to induce the formation of a hydrogel; and forming aggregates; wherein water is present to facilitate the formation of the hydrogel. Additionally, pellets obtained by the method of the present invention.

Inventors

• 라크먼 다니엘
• 마르코스 데이비드
• 래스몰 폴
• 커턴 켈리

Assignees

• 바인딩 솔루션스 리미티드

Dates

Publication Date

20260512

Application Date

20240904

Priority Date

20230905

Claims (20)

1. A method for manufacturing pellets, comprising the following steps: a. A step of providing a fine particulate substrate selected from metal ore, metal ore-containing waste, metal fines, iron residue, iron powder, mineral waste, carbonaceous material, arc furnace waste, or a combination thereof; b. A step of forming a substrate mixture by mixing a fine particle substrate with a binder formulation comprising at least one type of binding substance; c. a step of applying pressure to the substrate mixture to induce the formation of a hydrogel; and d. Step of forming aggregates; Here, water is present to facilitate hydrogel formation. method.
2. A method according to claim 1, wherein at least one type of binding material is a hydrogel-forming binding material.
3. A method according to claim 1 or 2, wherein the binder formulation comprises two or more types of binder substances.
4. A method according to any one of claims 1 to 3, wherein the first and second combining materials are mixed with a fine particle substrate to form a substrate mixture.
5. A method according to any one of claims 1 to 3, wherein a first binding material is mixed with a fine particle substrate to form a substrate mixture, and a second binding material is mixed with a hydrogel.
6. A method according to any one of claims 1 to 5, wherein the step of applying pressure to a substrate mixture to induce the formation of a hydrogel comprises passing the substrate mixture through a compression wheel.
7. A method in which, in any one of paragraphs 1 to 6, the applied force is in the range of 11 kN to 75 kN.
8. A method comprising the step of forming pellets from aggregates in any one of claims 1 to 7.
9. A method according to claim 8, wherein the step of forming pellets comprises passing the aggregate through a roller comprising a series of evenly spaced indentations along its length.
10. A method according to claim 8 or 9, wherein, after the step of forming a pellet, the method comprises the step of heating the pellet to a temperature in the range of 10°C to 250°C.
11. A method according to any one of claims 1 to 10, comprising granulating the aggregate before pelletizing.
12. A method according to claim 11, wherein granulation involves using a screen size in the range of about 1.75 mm to about 10 mm.
13. A method according to any one of claims 1 to 12, wherein the fine particle substrate comprises water in the range of about 0.5 wt% to about 10 wt%.
14. A method according to claim 13, wherein the fine particulate substrate contains water in the range of about 1 wt% to about 6 wt%.
15. A method according to any one of claims 1 to 14, wherein the fine particle substrate comprises a metal.
16. A method according to any one of claims 1 to 15, wherein the fine particle substrate comprises iron.
17. A method according to any one of claims 1 to 16, wherein the fine particle substrate is provided in an amount of about 70 wt% to about 99.9 wt% of the pellet.
18. A method according to any one of claims 1 to 17, wherein the binding material is selected from natural polymers, synthetic polymers, cellulosic materials, glycerolipids, polysaccharides, inorganic binding materials, or combinations thereof.
19. A method according to claim 18, wherein the binding material is selected from cellulose fibers, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxyethyl methyl cellulose (MHEC), polyacrylamide resin, polyvinyl alcohol, phenol formaldehyde resin, glycerolipids, polyacrylate, styrene-acrylate copolymer, one or more silicates, or a combination thereof.
20. A method according to claim 18 or 19, wherein the binding material is selected from cellulose fiber, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), polyacrylamide resin, polyvinyl alcohol, one or more silicates, polyacrylamide, ethyl acrylate styrene (EA), glyceryl triacetate, glyceryl diacetate, phenol-formaldehyde resin, or a combination thereof.

Description

pellets The present invention relates to a method for producing pellets from a particulate substrate and a binder, in particular a method for inducing hydrogel formation, and pellets obtained using the method. Although carbon and various metals and metal ores are abundant in the Earth's core, their available quantities are limited. The mining and smelting of metal ores and metals, such as iron, incur environmental costs, particularly in relation to pollution. Therefore, it is desirable to maximize waste recycling, which consequently reduces the amount of waste that must be handled and stored—for example, in the case of iron waste—typically through long-term storage in landfills or ponds. The manufacture of pellets from carbonaceous materials, fine metal particles, and metal ores is generally known in the relevant technical field. Often, a binder is used to bind particles together to form pellets. In the pelletization process, the binder is typically added as a powder. However, powder can be difficult to process into pellets strong enough to be stable and transportable to the site of use as well as within large-scale processing plants at their destination. Powdered binders can also explode or easily escape into the atmosphere. This can be financially disadvantageous due to material loss, pose a risk of direct human injury, and act as a hazardous factor that can have short-term toxic effects or cause long-term disease upon inhalation. Furthermore, pelletization processes using powders often yield inconsistent results, and this can become a problem when scaling up production due to the difficulty of achieving efficient powder dispersion in industrial-scale mixers. Additionally, interference between binder components can occur due to the influence of temperature and pressure. The use of powders can also affect differences in solubilization in unpredictable ways. This means that significant testing is required before industrial use, making the transition from formulation to industrial pelletization more difficult and increasing costs. Therefore, it would be desirable to develop a pelletizing process that provides improved ease of manufacture without loss of strength and stability. The present invention is intended to overcome or improve at least some aspects of this problem. Accordingly, in a first aspect of the present invention, a method for manufacturing pellets is provided, comprising the steps of: providing a particulate substrate selected from metal ore, metal ore-containing waste, metal fine powder, iron residue, iron powder, mineral waste, carbonaceous material, arc furnace waste, or a combination thereof; mixing the particulate substrate with a binder formulation comprising at least one binding material to form a substrate mixture; applying pressure to the substrate mixture to induce the formation of a hydrogel; and forming aggregates; wherein water is generally present to facilitate the formation of the hydrogel. The formation of a hydrogel through mechanically induced gelation allows the binder formulation to be dispersed more efficiently through the particulate substrate in the final pellet product. Although not strictly theoretical, it is believed that the formation of the hydrogel not only enhances the strength of the final pellet by binding the substrate particles together, but also acts as a processing aid because the binder formulation can be better dispersed in hydrogel form, thereby providing a lubricating effect. Overall, this improves the processing of the pellets, leading to more consistent results. Additionally, binders capable of forming hydrogels are dispersed more easily than powder binders in industrial-scale mixers. Furthermore, the incorporation of a binder capable of forming hydrogels enables the easy dispersion of additional powder binders, thereby resolving the issues associated with the sole use of powder binders. Consequently, this results in improved efficiency by reducing mechanical load and overheating. Furthermore, it has been noted that, because gelation enhances binding properties and allows polymer bonding to be strengthened by any existing binding material that does not directly form part of the hydrogel, less binding agent is required to achieve strength similar to known binding agent formulations. Additionally, the final pellets produced by the method of the present invention have surprisingly been found to be stronger pellets with higher strength and stiffness, which reduces the need for post-manufacturing heating (e.g., drying or curing processes) of the pellets to stabilize them for storage, transport, and use. This offers significant environmental benefits in that less energy is required to produce pellets of sufficient strength from particulate material. Furthermore, process efficiency is introduced in that pelletization can be completed rapidly without the need for heating equipment or delays that may be caused by additional heating stages. Moreover, the pellets