公开(公告)号：US10703659B2

公开(公告)日：2020-07-07

申请号：US15935850

申请日：2018-03-26

Applicant: KURITA WATER INDUSTRIES LTD.

Inventor： Mizuyuki Sakai ,  Yukimasa Shimura

IPC: C11D3/37 ,  C11D7/26 ,  C02F5/10 ,  C11D3/20 ,  B08B3/04 ,  B08B3/02 ,  F22B37/52 ,  C08F120/06 ,  C08L33/02 ,  C23F14/02 ,  C11D11/00

Abstract: A scale remover that efficiently removes scale deposited inside a boiler without corroding a boiler includes polyacrylic acid and polymethacrylic acid and/or salts thereof.

公开(公告)号：US10384966B2

公开(公告)日：2019-08-20

申请号：US15115493

申请日：2015-01-26

Applicant: KURITA WATER INDUSTRIES LTD.

Inventor： Mizuyuki Sakai ,  Yukimasa Shimura

IPC: C11D3/37 ,  C11D7/26 ,  C02F5/10 ,  C11D3/20 ,  B08B3/04 ,  B08B3/02 ,  F22B37/52 ,  C11D11/00 ,  C08F120/06 ,  C08L33/02 ,  C23F14/02

Abstract: Provided are a method for removing scale and a scale remover that can efficiently remove scale deposited inside a boiler can or the like in an addition amount of chemicals permissible in terms of cost without corroding a boiler, particularly can efficiently remove scale deposited inside a boiler can even in a facility operated with feed water containing high-concentration iron. A method for removing scale deposited in a system of a steam generating facility, wherein polyacrylic acid having a weight-average molecular weight of more than 20,000 and 170,000 or less and/or a salt thereof is added to feed water of the steam generating facility. When the feed water contains iron, polymethacrylic acid having a weight-average molecular weight of more than 1,000 and 100,000 or less and/or a salt thereof is further added in combination.

公开(公告)号：US09834462B2

公开(公告)日：2017-12-05

申请号：US14780794

申请日：2014-03-27

Applicant: KURITA WATER INDUSTRIES LTD.

Inventor： Mizuyuki Sakai ,  Yukimasa Shimura

IPC: C02F1/00 ,  C02F5/08 ,  C02F5/10 ,  C02F1/68 ,  F22B37/52 ,  C11D3/37 ,  C11D11/00 ,  C23F11/173 ,  C23F14/02 ,  C02F1/66

CPC classification number: C02F5/10 ,  C02F1/66 ,  C02F1/68 ,  C02F2303/14 ,  C02F2303/22 ,  C02F2307/00 ,  C11D3/3757 ,  C11D11/0041 ,  C23F11/173 ,  C23F14/02 ,  F22B37/52

Abstract: Provided is a method for removing a scale in a steam generation facility, whereby it becomes possible to remove a scale deposited on the inside of a boiler vessel during the operation of a boiler without causing corrosion of the boiler. A method for removing a scale in a steam generation facility is disclosed, wherein in the steam generation facility, a pH of boiler water is adjusted to 11.3 or more, and a polyacrylic acid having a weight average molecular weight that is 0.50 to 2.00 times a reference weight average molecular weight as calculated from the following calculation formula (1), or a salt thereof, is added in accordance with the pH value of the boiler water during the operation of a boiler, thereby removing a scale deposited on the inside of a boiler vessel: Reference weight average molecular weight=−8462×{(pH value)−11.3}+61538  (1).