US20260085376A1 - Method of producing iron ore pellets - Google Patents

Method of producing iron ore pellets

Info

Publication number
US20260085376A1
US20260085376A1 US19/106,634 US202319106634A US2026085376A1 US 20260085376 A1 US20260085376 A1 US 20260085376A1 US 202319106634 A US202319106634 A US 202319106634A US 2026085376 A1 US2026085376 A1 US 2026085376A1
Authority
US
United States
Prior art keywords
ore
iron ore
core
pellets
mass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
US19/106,634
Other languages
English (en)
Inventor
Kenta Takehara
Takahide Higuchi
Naoto Nakamura
Kenya HORITA
Shohei Fujiwara
Yuji Iwami
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
JFE Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by JFE Steel Corp filed Critical JFE Steel Corp
Publication of US20260085376A1 publication Critical patent/US20260085376A1/en
Pending legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/16—Sintering; Agglomerating
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/2406—Binding; Briquetting ; Granulating pelletizing
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/2413—Binding; Briquetting ; Granulating enduration of pellets
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/242—Binding; Briquetting ; Granulating with binders
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/242—Binding; Briquetting ; Granulating with binders
    • C22B1/243—Binding; Briquetting ; Granulating with binders inorganic

Definitions

  • the present disclosure relates to a method of producing iron ore pellets.
  • Iron ore pellets are made from iron ore powder granulated to have properties (such as size, strength, and reducibility) suitable for feeding into a blast furnace or solid reduction furnace.
  • properties such as size, strength, and reducibility
  • iron ore pellets are typically produced by the processes of grinding iron ore material to obtain fine ore, mixing the fine ore with a binder and optional auxiliary material to obtain a mixture, granulating the mixture to obtain green pellets, and firing the green pellets to obtain iron ore pellets.
  • pellets before firing in granulated form are referred to as “green pellets”.
  • securing the strength of green pellets is important in order to suppress pulverization of the green pellets during handling before being put into the kiln and to suppress adherence of resulting powder to the kiln. Further, suppressing bursting of the green pellets is important to secure the strength of the iron ore pellets after firing. Bursting is a phenomenon in which green pellets burst due to the pressure of vapor generated from inside the green pellets during drying and when water of crystallization is removed. Bursting causes cracks in the green pellets, which significantly decreases the strength of the iron ore pellets after firing.
  • the green pellets become denser and are more prone to bursting. That is, it has been difficult to both secure the strength of the green pellets and suppress bursting.
  • the inventors have conducted extensive studies and have discovered that by using iron ore having a particle size of 1 mm or less, obtained by grinding iron ore material, as well as iron ore having a particle size of more than 1 mm, obtained without grinding iron ore material, and by mixing and granulating the iron ore to produce green pellets, it is possible to secure drop strength of green pellets and suppress bursting.
  • green pellets are obtainable that have high strength and can suppress bursting.
  • FIG. 2 is a diagram schematically illustrating growth processes of green pellets in granulation processes according to an embodiment of the present disclosure and comparative examples.
  • FIG. 3 is a diagram schematically illustrating an electric furnace used for bursting temperature measurement.
  • core ore is used in addition to fine ore as the iron ore of green pellets.
  • the green pellets contain high-strength core ore, thereby securing strength of the green pellets.
  • the green pellets according to the present embodiment contain core ore having a large particle size, which decreases the rate of drying and water of crystallization removal.
  • the inclusion of core ore decreases the porosity of the green pellets, and denser green pellets are less likely to carry moisture. Further, fewer gas paths means vapor is less likely to be generated from inside the green pellets. As a result, bursting can be sufficiently suppressed.
  • the type and properties of the core ore are not particularly limited as long as the core ore is an iron ore having a total Fe content of 63 mass % or less and a particle size greater than 1 mm. Further, the core ore preferably has a particle size of 9.5 mm or less. When the particle size is 9.5 mm or less, the completed iron ore pellets are of a suitable size, and subsequent reduction processing and the like may be performed uniformly.
  • the mass fraction of the core ore is preferably 15 mass % or more of the total iron ore. This is because the more core ore, which has a larger volume than ordinary ground iron ore powder, the more effective even a small amount of binder such as bentonite can be, and strength enhancement and bursting suppression effects can be suitably obtained.
  • the mass fraction of particles having a particle size of more than 2.8 mm in the core ore is 15 mass % or more of the total iron ore. Even more preferably, the mass fraction of particles having a particle size of more than 2.8 mm in the core ore is 30 mass % or more of the total iron ore. In such a case, the mass fraction of the core ore having a particle size of more than 1 mm and 2.8 mm or less is not particularly restricted and may be 0 mass %.
  • the mass fraction of particles having a particle size of more than 4.8 mm in the core ore is 10 mass % or more of the total iron ore. More preferably, the mass fraction of particles having a particle size of more than 4.8 mm in the core ore is 25 mass % or more of the total iron ore. In such a case, the mass fraction of the core ore having a particle size of more than 1 mm and 4.8 mm or less is not particularly restricted and may be 0 mass %.
  • the mass fraction of the core ore is preferably 99 mass % or less of the total iron ore.
  • the mass fraction of the core ore is more preferably 75 mass % or less of the total iron ore.
  • the mass fraction of particles having a particle size greater than 1 mm is about 75 mass % at most.
  • FIG. 2 illustrates a schematic diagram (cross-section diagram) of growth processes in the granulation processes of green pellets.
  • layering granulation may occur, in which the fine ore 12 and binder and the like adhere to the surface of the core ore 10 in layers.
  • the weight fraction G can be expressed as in Expression (1) below.
  • the amount of binder is suitable relative to the amount of the fine ore, the effect of the binder can be suitably obtained, and strength can be secured.
  • the above range is more preferably 1.4 or more.
  • the above range is even more preferably 1.6 or more. The greater the amount of binder, the more easily pellet strength is secured, but the purity of the reduced iron is decreased, and therefore a range of 3.0 or less is preferred.
  • Iron ore pellets are produced by typical grinding, mixing, granulation, and firing processes.
  • the grinding process may be carried out using a typical ball mill or other grinding machine, and is only carried out on iron ore to be used as the fine ore.
  • the mixing process may be carried out using a typical concrete mixer or the like.
  • the granulation process may be carried out using a typical pelletizer, drum mixer, or the like.
  • the firing process may be carried out using a typical shaft furnace, rotary kiln, or the like.
  • a granulated green pellet preferably has a size of about 9.5 mm to 12 mm.
  • the size of the green pellets is less than 9.5 mm, the gas permeability degrades when filled into a blast furnace as fired pellets.
  • the size of the green pellets exceeds 12 mm, reducibility decreases.
  • the core ore and the fine ore were prepared in the mass fractions listed in Table 2 for a total of 5000 g, and mixed together with bentonite in a defined ratio for 3 min at 20 rpm using a concrete mixer.
  • the amount (mass %) of bentonite added to the total iron ore (sum of the core ore and the fine ore) is listed in Table 2 in the “Bentonite fraction” column.
  • the mixed materials were placed in a 1.2 m diameter pelletizer and granulation was carried out while adding water. Pellet particles of 9.5 mm to 12 mm were collected and rolled in a pelletizer for another 10 min to obtain green pellets.
  • the mix proportion of the core ore and the fine ore was adjusted so that the number of core ore particles in one green pellet averaged 1.0.
  • the volume fraction of the core ore to the green pellets and the number of core ore particles per green pellet are listed in Table 2. Porosity was 33%.
  • FIG. 3 is a schematic illustration of the electric furnace used for these examples.
  • a green pellet filling basket 32 filled with 200 g of green pellets was placed in an electric furnace 30 , and hot blast (air) at 200° C. (measured by a thermocouple 34 ) at a flow rate of 1.2 m/s was flowed from a heating gas supply 36 and held for 10 min. After the holding, samples were removed and checked for bursting. When no bursting was observed, the hot blast temperature was increased by a 40° C. increment, a new sample was placed in the furnace, and the same test was repeated. The temperature at which a sample was observed to burst was taken as the bursting temperature, and the results are listed in Table 2.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US19/106,634 2022-09-16 2023-07-11 Method of producing iron ore pellets Pending US20260085376A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2022148507 2022-09-16
JP2022-148507 2022-09-16
PCT/JP2023/025629 WO2024057693A1 (ja) 2022-09-16 2023-07-11 鉄鉱石ペレットの製造方法

Publications (1)

Publication Number Publication Date
US20260085376A1 true US20260085376A1 (en) 2026-03-26

Family

ID=90274602

Family Applications (1)

Application Number Title Priority Date Filing Date
US19/106,634 Pending US20260085376A1 (en) 2022-09-16 2023-07-11 Method of producing iron ore pellets

Country Status (7)

Country Link
US (1) US20260085376A1 (https=)
EP (1) EP4575021A4 (https=)
JP (1) JP7831577B2 (https=)
CN (1) CN119855926A (https=)
AU (1) AU2023341034A1 (https=)
CA (1) CA3262919A1 (https=)
WO (1) WO2024057693A1 (https=)

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54117301A (en) * 1978-03-03 1979-09-12 Kobe Steel Ltd Coarse particles-containing self-fluxing ore pellets
JPS57200529A (en) * 1981-06-02 1982-12-08 Nippon Steel Corp Preparation of sintered ore having iron ore fine powder highly compounded therein
JPS6237325A (ja) * 1985-06-27 1987-02-18 Nippon Kokan Kk <Nkk> 焼成塊成鉱およびその製造方法
JPS63149336A (ja) * 1986-12-15 1988-06-22 Nkk Corp 焼成塊成鉱の製造方法
JPS63219534A (ja) * 1987-03-09 1988-09-13 Kobe Steel Ltd 自溶性ペレットの製造方法
JP2001181745A (ja) 1999-12-27 2001-07-03 Kobe Steel Ltd Ｎａ含有スラグの水浸漬処理廃液を用いた鉄鉱石塊成鉱の製造方法
JP4154914B2 (ja) * 2002-04-04 2008-09-24 Ｊｆｅスチール株式会社 高炉用焼結鉱の製造方法
BRPI0306141B1 (pt) * 2002-08-21 2015-10-20 Nippon Steel & Sumitomo Metal Corp método de granulação de material de sinterização para a fabricação de ferro
JP4518895B2 (ja) * 2004-09-29 2010-08-04 新日本製鐵株式会社 焼結用原料の評価方法および配合設計方法
JP5098248B2 (ja) 2006-08-03 2012-12-12 新日鐵住金株式会社 製鉄用含鉄集塵ダスト類の造粒方法
JP5000366B2 (ja) * 2007-04-12 2012-08-15 新日本製鐵株式会社 焼結鉱の製造方法
JP2016176130A (ja) 2015-03-20 2016-10-06 株式会社神戸製鋼所 鉄鉱石焼成ペレット製造用生ペレットおよび鉄鉱石焼成ペレットの製造方法
JP7440768B2 (ja) 2020-08-18 2024-02-29 日本製鉄株式会社 高炉用焼成ペレット及び高炉用焼成ペレットの製造方法

Also Published As

Publication number Publication date
AU2023341034A1 (en) 2025-02-13
CN119855926A (zh) 2025-04-18
CA3262919A1 (en) 2025-06-09
JPWO2024057693A1 (https=) 2024-03-21
EP4575021A1 (en) 2025-06-25
JP7831577B2 (ja) 2026-03-17
WO2024057693A1 (ja) 2024-03-21
EP4575021A4 (en) 2025-07-02

Similar Documents

Publication Publication Date Title
US9988695B2 (en) Method for producing an agglomerate made of fine material containing metal oxide for use as a blast furnace feed material
JP5375742B2 (ja) 焼結原料の造粒方法
WO2013054471A1 (ja) 焼結原料の造粒方法
JP6519005B2 (ja) 焼結鉱の製造方法
CA1149617A (en) Porous iron ore pellets and process for manufacturing same
US20260085376A1 (en) Method of producing iron ore pellets
JP2003129139A (ja) 焼結原料の事前処理方法
CN110527826B (zh) 一种烧结过程抑制钙钛矿生成的烧结方法
JP2004137575A (ja) 焼結鉱の製造方法
JP7188126B2 (ja) 高炉用含炭非焼成ペレットの製造方法
EP4575020A1 (en) Iron ore pellet production method
JP2003306723A (ja) 高炉用焼結鉱の製造方法
JP6885386B2 (ja) 炭材内装粒子の製造方法および炭材内装焼結鉱の製造方法
JPH05339653A (ja) 焼結鉱原料の前処理法および製鉄用焼結鉱原料
CN114836616B (zh) 铁矿粉球团矿及其制备方法
JP7477064B1 (ja) 還元鉄の製造方法
JP6992734B2 (ja) 炭材内装粒子の製造方法および炭材内装焼結鉱の製造方法
EP4549601A1 (en) Non-fired pellets for reduction, and method for manufacturing same
JP2004285398A (ja) 焼結鉱の製造方法
EP4570930A1 (en) Method for producing iron ore pellets, and iron ore pellets
JP6809446B2 (ja) 炭材内装粒子の製造方法および炭材内装焼結鉱の製造方法
JP7024649B2 (ja) 焼結用原料の造粒方法
US20260043108A1 (en) Method for producing iron ore pellet
RU2025110796A (ru) Способ производства железорудных окатышей и железорудные окатыши
JP2016176122A (ja) 焼結鉱製造用の擬似粒子

Legal Events

Date Code Title Description
STPP Information on status: patent application and granting procedure in general

Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION