公开(公告)号：US20220220619A1

公开(公告)日：2022-07-14

申请号：US17607781

申请日：2020-01-09

Applicant: PRIMETALS TECHNOLOGIES JAPAN, LTD.

Inventor： Kosei TSUJI ,  Ryusuke NAKATSUKA ,  Masashi YOSHIKAWA ,  Takuya HIRATA

IPC: C23G1/08 ,  C23G3/02

Abstract: A method for pickling a steel plate having a first steel plate portion and a second steel plate portion which is connected to a tail end of the first steel plate portion and which requires a longer time for pickling than the first steel plate portion when pickled under the same condition includes: a step of pickling the steel plate by immersing the steel plate in an acid solution in at least one pickling tank while conveying the steel plate; a step of circulating the acid solution, through a circulation line connected to any of the at least one pickling tank, between the pickling tank and an oxidizing device disposed in the circulation line; a step of oxidizing Fe2+ in the acid solution to Fe3+ by the oxidizing device using a gaseous oxidant; and a feeding start step of, upon switching from pickling of the first steel plate portion to pickling of the second steel plate portion, starting feeding of a liquid oxidant for oxidizing Fe2+ in the acid solution to Fe3+ to any of the at least one pickling tank or to the circulation line.

公开(公告)号：US20220154351A1

公开(公告)日：2022-05-19

申请号：US17439720

申请日：2019-03-22

Applicant: PRIMETALS TECHNOLOGIES JAPAN, LTD.

Inventor： Kosei TSUJI ,  Ryusuke NAKATSUKA ,  Takahiro YAGI ,  Masashi YOSHIKAWA ,  Hideaki TAKATANI ,  Toyoaki YASUI ,  Takuya HIRATA

IPC: C23G3/02 ,  C23G1/08

Abstract: An acid solution preparation device is an acid solution preparation device for preparing an acid solution used for pickling of a steel plate, the device including a sealed tank for storing the acid solution, a gas supply part for supplying an oxygen-containing gas from outside of the sealed tank to the sealed tank, and a purge part for discharging a gas in the sealed tank to the outside.