公开(公告)号：US20210054479A1

公开(公告)日：2021-02-25

申请号：US16977378

申请日：2019-02-22

Applicant: JFE STEEL CORPORATION

Inventor： Nobuhiko ODA ,  Yuta HINO ,  Yuki TAKAKI ,  Yoshiaki NISHINA ,  Naoki KIKUCHI

IPC: C22B9/14 ,  C22B47/00 ,  C21C7/00

Abstract: A manufacturing method includes a first pulverization step of compressively pulverizing a manganese oxide-containing material containing at least manganese, calcium, silicon, iron, and phosphorus, which is used as a raw material, to form a composite in which a compound phase of nCaO.P2O5 is combined with at least one phase of a spinel phase and a calcium ferrite phase, which are ferromagnetic materials, and produce a first pulverized manganese oxide-containing material containing the composite; a first magnetic separation step of separating the first pulverized manganese oxide-containing material produced in the pulverization step into a magnetic substance and a non-magnetic substance under a magnetic force; and a step of recovering the non-magnetic substance separated in the first magnetic separation step as a manganese raw material.

公开(公告)号：US20230313330A1

公开(公告)日：2023-10-05

申请号：US18022802

申请日：2021-08-23

Applicant: JFE STEEL CORPORATION

Inventor： Nobuhiko ODA ,  Masanori TANNO ,  Rei YAMADA

IPC: C21C7/064 ,  C21C5/54

CPC classification number: C21C7/064 ,  C21C5/54 ,  C21C2300/08

Abstract: A method for efficiently manufacturing low-phosphorus molten steel by use of a steelmaking electric furnace, in which slag resulting from melting a solid iron source is effectively separated from molten steel, and thus a unit consumption of lime required to reduce a phosphorus content in the molten steel is reduced. The method includes: charging a solid iron source and an optional molten iron source and melting and heating these raw materials by using electric energy; partly or entirely removing slag generated during the melting; performing dephosphorization by adding dephosphorization flux; and tapping low-phosphorus molten steel thus refined, and in the method, a slag composition ratio being [CaO]/([SiO2]+[Al2O3]) of the slag to be removed is adjusted to be not less than 0.25 and not more than 0.70.

公开(公告)号：US20220259686A1

公开(公告)日：2022-08-18

申请号：US17626083

申请日：2020-07-02

Applicant: JFE STEEL CORPORATION

Inventor： Yumi MURAKAMI ,  Nobuhiko ODA ,  Hidemitsu NEGISHI ,  Ryo KAWABATA ,  Naoki KIKUCHI ,  Yusuke FUJII

IPC: C21C1/02

Abstract: A dephosphorization method using a top and bottom blown converter. This method uses a converter charged with molten iron and slag, to blow an oxygen-containing gas from a top-blowing lance, supply the gas from an inlet of a blowing hole, and supply a control gas from an opening toward an axial center. This method has: a slag top-surface position measurement step, with the top surface of the molten iron measured in advance, measuring an arbitrary position in a top surface of the slag; a slag top-surface difference calculation of slag thickness difference between the measured top-surface positions of the molten iron and the slag; and a jetting condition adjustment step of, using the obtained slag thickness, adjusting a jetting condition of the gas jetted from the top-blowing lance into an appropriate range. The top-blown jetting condition is adjusted by comparing the slag thickness and the depth of a surface depression.

公开(公告)号：US20230167518A1

公开(公告)日：2023-06-01

申请号：US17802389

申请日：2021-02-16

Applicant: JFE STEEL CORPORATION ,  JFE MINERAL & ALLOY COMPANY, LTD.

Inventor： Nobuhiko ODA ,  Yusuke FUJII ,  Shingo SATO ,  Ryo KAWABATA ,  Naoki KIKUCHI ,  Toshio SHIOTA ,  Ippei HIGUCHI

IPC: C21C7/068 ,  C21C5/35 ,  C21C5/36 ,  C22C35/00 ,  C22C33/06

CPC classification number: C21C7/068 ,  C21C5/35 ,  C21C5/36 ,  C22C35/005 ,  C22C33/06

Abstract: A method for producing low-carbon ferromanganese capable of achieving a high Mn yield. In producing low-carbon ferromanganese by blowing an oxidizing gas from a top-blowing lance onto a bath face of high-carbon ferromanganese molten metal accommodated in a reaction vessel provided with a top-blowing lance and bottom-blowing tuyere to perform decarburization, the slag composition during the blowing is adjusted so that a value of (CaO+MgO)/(Al2O3+SiO2) on a mass basis in the slag composition is not less than 0.4 but not more than 5.0. Also, agitation is performed under a condition that an agitation power density ε of an agitation gas blown through the bottom-blowing tuyere is not less than 500 W/t.

公开(公告)号：US20220154299A1

公开(公告)日：2022-05-19

申请号：US17601481

申请日：2020-04-02

Applicant: JFE STEEL CORPORATION

Inventor： Yumi MURAKAMI ,  Nobuhiko ODA ,  Yusuke FUJII ,  Goro OKUYAMA ,  Shota AMANO ,  Shinji KOSEKI ,  Shingo SATO ,  Yukio TAKAHASHI ,  Ryo KAWABATA ,  Naoki KIKUCHI ,  Atsuo YUASA

IPC: C21C5/46

Abstract: A top-blowing lance nozzle is configured to freely switch an adequate expansion condition so as to control an oxygen-blowing amount and a jetting velocity independently of each other without requiring a plurality of lance nozzles or a mechanically movable part. A lance nozzle is configured to blow refining oxygen to molten iron charged in a reaction vessel while a gas is blown from a top-blowing lance to the molten iron. One or more blowing holes for blowing a working gas are on an inner wall side surface of the nozzle, at a site where the lance nozzle has a minimum cross-sectional area in a nozzle axis direction or at a neighboring site of the site.

公开(公告)号：US20240417818A1

公开(公告)日：2024-12-19

申请号：US18698688

申请日：2022-07-21

Applicant: JFE STEEL CORPORATION

Inventor： Yoshihiro MIWA ,  Wataru TODO ,  Nobuhiko ODA

IPC: C21B11/10

Abstract: A method for predicting an impurity concentration of molten iron after refining of molten iron to be refined in an electric arc furnace facility includes inputting, into an impurity concentration prediction model, an amount of individual ferrous scrap material charged, the ferrous scrap material being classified by type, and at least one of the impurity concentration of molten iron in a preceding charge, an amount of residual molten iron in the preceding charge, and market transaction price information of an impurity; and outputting the impurity concentration of the molten iron in a subsequent charge.

公开(公告)号：US20230304110A1

公开(公告)日：2023-09-28

申请号：US18022791

申请日：2021-08-23

Applicant: JFE STEEL CORPORATION

Inventor： Nobuhiko ODA ,  Futoshi OGASAWARA ,  Kentaro KAKIGI ,  Takayoshi FUKUYAMA

IPC: C21C7/00 ,  C21C5/28 ,  C21C7/068

CPC classification number: C21C7/0025 ,  C21C5/28 ,  C21C7/068

Abstract: A method for producing chromium-containing molten steel from a raw material including a chromium-containing raw material includes a first step in which a slag basicity before rough decarburization by oxygen blowing is adjusted to be not less than 1.5 and not more than 3.0, a slag basicity after rough decarburization by oxygen blowing is adjusted to be not less than 2.0 and not more than 3.5, and then tapping is performed while slag containing a chromium oxide generated by the oxygen blowing is made to remain in the furnace, and a second step in which the slag containing a chromium oxide made to remain is reduced by using a carbon source or a metal source newly added into the same furnace so that chromium is recovered into molten steel. The slag basicity is determined by dividing a CaO concentration by an SiO2 concentration on a mass basis in the slag.