A combination for forming briquettes from electric arc furnace dust and electric arc furnace dust briquettes

Abstract

Summary of the Invention: What is disclosed is a composition for forming an electric arc furnace dust briquette, and an electric arc furnace dust briquette. The disclosed composition for forming an electric arc furnace dust briquette includes electric arc furnace dust and, a cellulose ether composition having a viscosity of about 4,000 cps to about 80,000 cps as a binder.

Description

Combination for forming briquette earth electric arc furnace and briquette electric arc furnace Technical field

[0001] The present disclosure relates to a composition for forming an electric arc furnace dust briquette, and in particular, to a composition for forming an electric arc furnace dust briquette, comprising a cellulose ether composition having a specific viscosity range as a binder, and an electric arc furnace dust briquette. Prior knowledge

[0002] Iron production processes are classified into a steelmaking process of preparing molten steel by pouring steel ore and / or scrap steel into a blast furnace along with coal, a steelmaking process of preparing high-purity molten steel by removing impurities from the molten steel, a casting process of making a semi-finished product such as a solid slab of non-solid molten steel, and a rolling process of making a finished steel product by processing the semi-finished product such as a slab.

[0003] In an integrated iron and steelmaking process, molten iron is produced using 90% by weight to 100% by weight of steel ore and 0% to 10% by weight of reduced iron (scrap) or scrap iron as raw materials. In the electric arc furnace steelmaking process, molten iron is produced using 90% by weight to 95% by weight of scrap iron and 5% by weight to 10% by weight of steel ore as raw materials.

[0004] In the electric arc furnace steelmaking process, 1.2 wt% to 1.5 wt% of the soil, i.e., electric arc furnace dust (EAFD), relative to 100 wt% of the final molten iron, is generated during the smelting of scrap iron and ore-produced steel. This electric arc furnace dust contains 25~35 wt% of the steel component in the highest content, and 18~28 wt% of zinc and 2~5 wt% of lead, which are known as the main recyclable materials.

[0005] There are various methods for recovering valuable metals from steel dust, including the Waelz method using a sintering furnace and the ZIA (Zinc Steel Presence) method. Recently, methods for recovering valuable metals by regenerating electric arc furnace dust after briquetting the electric arc furnace dust in a calcining furnace have been developed and are commercially available.

[0006] Electric arc furnace dust is a microparticle with an average particle diameter of about 1㎛, and a relatively large amount of binder is required for briquetting the microparticles. In addition, to form briquettes with high compressive strength, the briquetting press process requires a drying process at a temperature of about 140°C to about 150°C and the use of molasses as a main binder.

[0007] However, when molasses is used as a binder, the following disadvantages may arise.

[0008] In the first phase, with the newly growing bioethanol industry, molasses may face a shortage and high price increases.

[0009] Secondly, molasses also gives off a bad odor during the process.

[0010] Due to the heat applied during a drying process in the electric arc furnace dust briquette production process, latent heat may accumulate in the arc of the briquetted coal in the furnace dust. This phenomenon may lead first to the combustion of the molasses and then secondly to the coal acting as a reducing agent, increasing the fire hazard.

[0011] In addition, molasses in a viscous liquid form may increase in viscosity with decreasing temperature and may stick to the storage tank, pipe and nozzle during storage, transfer and spraying. To avoid these defects, preventive equipment (for example, a high-pressure pump and a heating system) is required. Therefore, when molasses is used as a binder, the process of making soil briquette electric arc furnace may be complicated.

[0012] The viscosity of molasses may vary depending on the source, supplier, and timing of its supply because molasses is of natural origin, and it may be difficult to maintain consistent quality of kiln dust briquettes.

[0013] Molasses is a liquid and has a low density, and a large amount of molasses, along with a high storage capacity, is required for it. The large amount of molasses transported may also lead to increased transportation costs. Detailed description of the invention Technical problem

[0014] The present invention provides a composition for forming electric arc furnace dust briquettes, the composition comprising a cellulose ether composition with a specific viscosity range as a binder.

[0015] The present invention provides an electric arc furnace dust briquette formed from a composition for forming an electric arc furnace dust briquette. Technical solution

[0016] According to one aspect of the present invention, a composition for forming an electric arc furnace dust briquette comprises: an electric arc furnace dust; and a cellulose ether composition having a viscosity of about 4,000 to about 80,000 cps as a binder.

[0017] Electric arc furnace dust may have an average particle diameter of about 0.3 ㎛ to about 1.0 ㎛.

[0018] The cellulose ether composition may not include carboxymethyl cellulose (CMC).

[0019] The cellulose ether composition may include at least one compound selected from the group consisting of methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), and ethylhydroxyethyl methyl cellulose (MEHEC).

[0020] Methyl cellulose (MC) may have a degree of methyl group substitution of about 18 wt% to about 32 wt%, hydroxyethyl cellulose (HEC) may have a degree of hydroxy group substitution of about 20 wt% to about 80 wt%, hydroxypropyl cellulose (HPC) may have a degree of hydroxypropyl group substitution of about 20 wt% to about 80 wt%, hydroxypropyl methyl cellulose (HPMC) may have a degree of methyl group substitution of about 18 wt% to about 32 wt% and a degree of hydroxypropyl group substitution of about 2 wt% to about 14 wt%, and hydroxymethyl cellulose (HEMC) may have a degree of methyl group substitution of about 18 wt% to about 32 wt% and a degree of hydroxy group substitution of about 2 wt% to about 14 wt%.

[0021] The amount of cellulose ether composition may range from about 0.01 part to about 15.0 parts to about 100 parts by weight of electric arc furnace dust.

[0022] The composition for forming electric arc furnace dust briquettes may also include an additional binder in an amount of greater than 0 to about 15.0 parts by weight or less to about 100 parts by weight of electric arc furnace dust.

[0023] The additional adhesive may include at least one compound selected from the group consisting of molasses, epoxy resin, glycerol, guar gum, acacia gum, lignosulfonate, nitrophenol, organosilicon, polyacrylamide, polyvinyl acetal, polyvinyl alcohol, starch, pregelatinized starch, starch ether, and liquor.

[0024] The composition for forming the electric arc furnace dust briquette may also include water in an amount of greater than 0 to about 10.0 parts by weight or less to about 100 parts by weight of the electric arc furnace dust.

[0025] The composition for forming electric arc furnace dust briquettes may not contain glycerin.

[0026] According to one aspect of the present invention, there is provided an electric arc furnace dust briquette produced from a composition for forming an electric arc furnace dust briquette according to any of the above-mentioned configurations.

[0027] The electric arc furnace dust briquette may include a cellulose ether composition and may not contain glycerin. Beneficial effects of the invention

[0028] According to one or more embodiments, a composition for forming an electric arc furnace dust briquette may include a cellulose ether composition in the form of a colorless and odorless solid powder having a specific viscosity range as a binder, and thereby may improve an odor-free working environment. The total amount of binder used may be reduced (to about one-tenth the amount of molasses used when molasses alone is used (100%)). Accordingly, fire hazards may be improved and the process of producing an electric arc furnace dust briquette may be simplified. A high-strength electric arc furnace dust briquette may be produced while maintaining more stable supply and demand conditions and a more stable price compared to molasses. How to invent

[0029] Hereinafter, configurations of a composition for forming electric arc furnace dust briquettes will be described in detail.

[0030] According to one aspect of the present disclosure, a composition for forming an electric arc furnace dust briquette comprises: an electric arc furnace dust (EAFD); and a cellulose ether composition having a viscosity of about 4,000 to about 80,000 centipoise (CPS) or megapascals as a binder. As used herein, the term "electric arc furnace dust" may refer to dust generated during a steelmaking process in electric arc furnace steelmaking processes. As used herein, the term "viscosity of the cellulose ether composition" may refer to a viscosity of a 2 weight percent aqueous solution of the cellulose ether composition at about 20 ± 0.1 ° C measured with a Brookfield DV-II+Pro (HA spindle).

[0031] When the cellulose ether composition has a viscosity of less than 4000 cps, the viscosity of the solution (e.g., aqueous solution) containing the cellulose ether composition may be so low that the bonding strength of the cellulose ether composition to the electric arc furnace dust is reduced. When the cellulose ether composition has a viscosity of more than 80000 cps, the molecular weight of the cellulose ether composition may be so high that the water solubility of the cellulose ether composition is reduced, and the bonding strength to the electric arc furnace dust may not be high enough.

[0032] The cellulose ether composition may have a viscosity, for example, of about 5000 cps ~ about 70,000 cps, and in some configurations, of about 6000 cps ~ about 60,000 cps, and in some configurations, of about 7000 cps ~ about 50,000 cps, and in some other configurations, of about 8000 cps ~ about 40,000 cps, and in still other configurations, of about 9000 cps ~ about 30,000 cps, and in still other configurations, of about 10,000 cps ~ about 20,000 cps.

[0033] Electric arc furnace dust may have an average particle diameter of about 0.3 CPS ~ about 1.0 ㎛.

[0034] The cellulose ether composition may cause electric arc furnace dust particles to stick together.

[0035] The cellulose ether composition may have good solubility in water and therefore may not deposit on the inner surface of the nozzle when sprayed in the form of an aqueous solution through a nozzle, and may therefore not clog the nozzle. The cellulose ether composition may be stored and transported as a solid powder alone or in a mixture with electric arc furnace dust, and may then be mixed with water at the final stage of use. Accordingly, the use of smaller and simplified storage equipment and simplified transportation equipment is possible. The cellulose ether composition may provide the same binding effect of molasses even using a smaller amount of molasses, may have lower fire hazards and may have a lower cost than molasses, and may therefore reduce the cost of materials. The cellulose ether composition may be more stable in terms of supply and demand and price than molasses.

[0036] The cellulose ether composition may not include carboxymethyl cellulose (CMC). When the cellulose ether composition includes carboxymethyl cellulose (CMC), the electric arc furnace dust briquette produced from the composition for forming the electric arc furnace dust briquette may have low strength.

[0037] The cellulose ether composition may include at least one compound selected from the group consisting of methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), and methylethyl hydroxyethyl cellulose (MEHEC).

[0038] Methyl cellulose (MC) may have a degree of methyl group substitution of about 18 wt% ~ about 32 wt%, hydroxyethyl cellulose (HEC) may have a degree of hydroxy group substitution of about 20 wt% ~ about 80 wt%, hydroxypropyl cellulose (HPC) may have a degree of hydroxypropyl group substitution of about 20 wt% ~ about 80 wt%, hydroxypropyl methyl cellulose (HPMC) may have a degree of methyl group substitution of about 18 wt% ~ about 32 wt% and a degree of hydroxypropyl group substitution of about 2 wt% ~ about 14 wt%, and hydroxymethyl cellulose (HEMC) may have a degree of methyl group substitution of about 18 wt% ~ about 32 wt% and a degree of hydroxy group substitution of about 2 wt% ~ about 14 wt%. Have weight.

[0039] The amount of cellulose ether composition may be from about 0.01 parts to about 15.0 parts per 100 parts by weight of electric arc furnace dust. When the amount of cellulose ether composition is within this range, a high strength of electric arc furnace dust briquette may be achieved using a lower amount of molasses.

[0040] The composition for forming electric arc furnace dust briquettes may also include an additional binder in an amount of greater than 0 to about 15.0 parts by weight or less to about 100 parts by weight of electric arc furnace dust. When the amount of additional binder is in this range, the amount of cellulose ether composition used may be reduced so that the cost of preparing the composition for forming electric arc furnace dust briquettes may also be reduced. In addition, the composition for forming electric arc furnace dust briquettes may increase the drying rate.

[0041] The additional adhesive may include at least one compound selected from the group consisting of molasses, epoxy resin, glycerol, guar gum, acacia gum, lignosulfonate, nitrophenol, organosilicon, polyacrylamide, polyvinyl acetal, polyvinyl alcohol, starch, pregelatinized starch, starch ether, and liquor.

[0042] The composition for forming electric arc furnace dust briquettes may also include water in an amount of greater than 0 to about 10.0 parts by weight or less to about 100 parts by weight of electric arc furnace dust. When the amount of water is in this range, an easy-to-handle composition having a uniform composition may be obtained, and some components in the composition may be prevented from sticking to the surface of a molding machine and in a furnace dust briquette forming process.

[0043] The composition for forming electric arc furnace dust briquettes may not contain glycerin. When the composition for forming electric arc furnace dust briquettes contains glycerin, the drying rate of the electric arc furnace dust briquettes prepared from the composition may be slowed down, resulting in a decrease in thermal efficiency.

[0044] According to another aspect of the present disclosure, an electric arc furnace dust briquette is formed from a composition for forming an electric arc furnace dust briquette according to any of the above-mentioned configurations.

[0045] A method for producing electric arc furnace dust briquettes from the composition for forming electric arc furnace dust briquettes according to any of the above-mentioned configurations is as follows. The method may include placing the composition for forming electric arc furnace dust briquettes into a mold, pressing the mold at a predetermined pressure, and drying the resulting compacted product to thereby form an electric arc furnace dust briquette.

[0046] The electric arc furnace dust briquette may include a cellulose ether composition and may not contain glycerin.

[0047] One or more embodiments of the present disclosure are described in detail with reference to the following examples. However, these examples are for illustrative purposes only and are not intended to limit the scope of one or more embodiments of the present disclosure.

[0048] [Examples]

[0049] Examples 1 to 9 and Comparative Examples 1 and 2

[0050] (Preparation of a composition for forming an electric arc furnace dust briquette)

[0051] Electric arc furnace dust (average particle diameter: about 0.3 ㎛) obtained from a company having an electric steelmaking process in South Korea, hydroxypropyl methyl cellulose, and optionally molasses (KCIE CO., LTD, solids percentage: 77.2%; total sugar content: 49.3% by weight) were mixed together to obtain a first composition. Then, distilled water was added to the first composition, and thus a composition was obtained to form an electric arc furnace dust briquette. The amounts of the components in each of the compositions of Examples 1 to 9 and Comparative Examples 1 and 2 are shown in Table 1.

[0052] (Electric arc furnace dust briquette making)

[0053] Fifty electric arc furnace dust briquettes for each of the prepared compositions were made to form an electric arc furnace dust briquette at a pressure of about 205 atmospheres with a briquette machine (available from JEIL Machinery Co., LTD., JCB250T), and thirty of them were selected and twenty of them were discarded, including the first ten and the last ten. The electric arc furnace dust briquettes were dried in an oven at about 145°C for about 3 hours. The weight of each electric arc furnace dust briquette was about 10~20 g.

[0054] Comparative Example 3

[0055] (Preparation of a composition for forming an electric arc furnace dust briquette)

[0056] The composition for forming an electric arc furnace dust briquette was prepared in the same manner as in Example 1, except that carboxymethyl cellulose (CMC) (available from Ashiland, AqualonTM viscosity: 6,000cps) was used instead of hydroxypropyl methyl cellulose (HPMC1). The amounts of the components in the composition of Comparative Example 3 are shown in Table 1.

[0057] Comparative Example 4

[0058] (Preparation of a composition for forming an electric arc furnace dust briquette)

[0059] Electric arc furnace dust (average particle diameter: about 0.3 ㎛) obtained from a company with an electric steelmaking process in Korea and molasses (KCIE CO., LTD, solids content: 77.2 wt%, total sugar content: 49.3 wt%) were mixed together to obtain a first composition. Then, distilled water was added to the first composition, thereby obtaining a composition for forming an electric arc furnace dust briquette. The amounts of the components in the composition of Comparative Example 4 are shown in Table 1.

[0060] (Electric arc furnace dust briquette production)

[0061] Electric arc furnace dust briquettes were produced in the same manner as in Examples 1 to 9 and Comparative Examples 1 and 2, except that the composition for forming a comparative electric arc furnace dust briquette of Example 4 was replaced by the composition for forming a charcoal furnace instead of the soil briquette compositions prepared in Examples 1 to 9 and Comparative Examples 1 and 2. The weight of each electric arc furnace dust briquette was about 10~20 grams.

Table 1

[0062] Evaluation Example

[0063] Evaluation Example 1

[0064] The impact strength due to falling and the compressive strength to electric arc of the kiln dust briquettes produced in Examples 1 to 9 and Comparative Examples 1 to 4 were examined by the following methods. The results obtained are shown in Table 2.

[0065] (Fall impact strength)

[0066] After twenty electric arc furnace dust briquettes produced in each of the examples were dropped ten times from a height of 165 cm, the total weight of the remaining portion of the electric arc furnace dust briquettes having a size of 5 ㎛ or more was determined as a percentage by weight relative to the total weight of the electric arc furnace dust briquettes of each example before dropping. The percentage value obtained by weight was evaluated as a drop impact strength. A high weight percentage R obtained means that the electric arc furnace dust briquettes had a higher drop impact strength. This drop impact strength is a criterion for estimating the drop percentage with a number of drops while each electric arc furnace dust briquette is transported by a conveyor belt.

[0067] (Compressive strength evaluation)

[0068] The maximum arc strength of the furnace dust briquettes when compressed at a speed of 5㎛ / min was measured with a compression material tester (SHINGANG PRECISION CO., LTD., AD-Global Material Tester-KN) and recorded as a compressive strength. This compressive strength is a criterion for estimating the damage ratio of its weight when the arc furnace dust briquettes are stored in a storage tank.

Table 2

[0069] Referring to Table 2, it was found that the electric arc furnace dust briquettes produced in Samples 1 to 9 had higher drop impact strength and higher compressive strength compared to the electric arc furnace dust briquettes produced in Comparative Samples 1 to 4.

[0070] It is to be understood that the configurations described herein are exemplary and not restrictive. The description of features or aspects within each configuration should generally be construed as including other similar features or aspects in other configurations. While one or more configurations have been described with reference to the figures, it is to be understood that those of ordinary skill in the art may make various changes in form and detail without departing from the spirit and scope defined by the following claims. Complaint 1. A composition for forming an electric arc furnace dust briquette, comprising: Electric arc furnace dust; and A cellulose ether composition having a viscosity of about 4,000 to about 80,000 cps as an adhesive. 2. The composition of claim 1, wherein the electric arc furnace dust has an average particle diameter of about 0.3 wt. % to about 1.0 ㎛. 3. The composition of claim 1, wherein the cellulose ether composition does not include carboxymethyl cellulose (CMC). 4. The composition of claim 3, wherein the cellulose ether composition comprises at least one compound selected from the group consisting of methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), and methyl ethyl hydroxyethyl cellulose (MEHEC). 5. The composition of claim 4, wherein methyl cellulose (MC) has a degree of methyl group substitution of about 18 wt% to about 32 wt%, hydroxyethyl cellulose (HEC) has a degree of hydroxy group substitution of about 20 wt% to about 80 wt%, hydroxypropyl cellulose (HPC) has a degree of hydroxypropyl group substitution of about 20 wt% to about 80 wt%, hydroxypropyl methyl cellulose (HPMC) has a degree of methyl group substitution of about 18 wt% to about 32 wt% and a degree of hydroxypropyl group substitution of about 2 wt% to about 14 wt%, and hydroxymethyl cellulose (HEMC) has a degree of methyl group substitution of about 18 wt% to about 32 wt% and a degree of hydroxy group substitution of about 2 wt% to about 14 wt%. 6. The composition of claim 1, wherein the amount of cellulose ether composition is from about 0.01 part to about 15.0 parts by weight to about 100 parts by weight of electric arc furnace dust. 7. The composition of claim 1, further comprising an additional binder in an amount of greater than 0 to about 15.0 parts or less by weight to about 100 parts by weight of electric arc furnace dust. 8. The composition of claim 7, wherein the additional adhesive comprises at least one compound selected from the group consisting of molasses, epoxy resin, glycerol, guar gum, acacia gum, lignosulfonate, nitrophenol, organosilicon, polyacrylamide, polyvinyl acetal, polyvinyl alcohol, starch, starch pregelatinized, starch ether, and liquor. 9. The composition of claim 1 further comprising water in an amount of greater than 0 to about 10.0 parts by weight or less to about 100 parts by weight of electric arc furnace dust. 10. The composition of claim 1, wherein the composition does not contain glycerin. 11. Electric arc furnace dust briquettes produced from the composition for forming electric arc furnace dust briquettes according to any one of claims 1 to 10. 12. The electric arc furnace dust briquette of claim 11, wherein the electric arc furnace dust briquette comprises a cellulose ether composition and does not contain glycerin. Abstract of the invention What is disclosed is a composition for forming an electric arc furnace dust briquette, and an electric arc furnace dust briquette. The disclosed composition for forming an electric arc furnace dust briquette includes electric arc furnace dust and, a cellulose ether composition having a viscosity of about 4,000 cps to about 80,000 cps as a binder.

Claims

Claim Amendment 1. A composition for forming an electric arc furnace dust briquette, comprising: an electric arc furnace dust; and a cellulose ether compound having a viscosity of 4,000 to 80,000 cps as a binder , wherein the cellulose ether compound does not include carboxymethylcellulose (CMC).

2. The composition of claim 1, wherein the electric arc furnace dust has an average particle diameter of 0.3 wt% to 1.0㎛.

3. The composition of claim 1, wherein the cellulose ether compound comprises at least one compound selected from the group consisting of methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), and methyl ethyl hydroxyethyl cellulose (MEHEC).

4. The composition of claim 3, wherein the methyl cellulose (MC) has a degree of substitution of methyl group of 18wt% to 32wt%, the hydroxyethyl cellulose (HEC) has a degree of substitution of hydroxyethyl group of 20wt% to 80wt%, the hydroxypropyl cellulose (HPC) has a degree of substitution of hydroxypropyl group of 20wt% to 80wt%, the hydroxypropyl methyl cellulose (HPMC) has a degree of substitution of methyl group of 18wt% to 32wt% and a degree of substitution of hydroxypropyl group of 2wt% to 14wt%, and the hydroxyethyl methyl cellulose (HEMC) has a degree of substitution of methyl group of 18wt% to 32wt% and a degree of substitution of hydroxyethyl group of 2wt% to 14wt%.

5. The composition of claim 1, wherein an amount of the cellulose ether compound is from 0.01 parts to 15.0 parts by weight with respect to 100 parts by weight of the electric arc furnace dust.

6. The composition of claim 1, further comprising an additional binder in an amount of greater than 0 to 15.0 parts or less by weight with respect to 100 parts by weight of the electric arc furnace dust.

7. The composition of claim 6, wherein the additional binder comprises at least one compound selected from the group consisting of molasse, epoxy resin, glycerol, guar gum, acacia gum, lignosulfonate, nitrophenol, organosilicon, polyacrylamide, polyvinyl acetal, polyvinyl alcohol, starch, pregelatinized starch, starch ether, and liquor.

8. The composition of claim 1, further comprising water in an amount of greater than 0 to 10.0 parts or less by weight with respect to 100 parts by weight of the electric arc furnace dust.

9. The composition of claim 1, wherein the composition does not comprise glycerin.

10. An electric arc furnace dust briquette manufactured from the composition for forming an electric arc furnace dust briquette according to any one of the preceding.

11. The electric arc furnace dust briquette of claim 10, wherein the electric arc furnace dust briquette comprises a cellulose ether compound and does not comprise glycerin.