The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 2019
Filed:
Oct. 14, 2014
Jfe Engineering Corporation, Tokyo, JP;
Shigeki Fujiwara, Tokyo, JP;
Eri Watanabe, Tokyo, JP;
Yohei Tomida, Tokyo, JP;
Koji Fuchigami, Tokyo, JP;
Takeshi Tsuji, Tokyo, JP;
Yasuhiro Minamizato, Tokyo, JP;
Yasuto Ando, Tokyo, JP;
Yoshitaka Moriyama, Tokyo, JP;
JFE ENGINEERING CORPORATION, Tokyo, JP;
Abstract
A method and apparatus for removing soluble silica efficiently from accompanied water, produced from wells containing calcium ion, soluble silica, and sulfate ion, and not clogging a reverse osmosis membrane in the reverse osmosis membrane treatment process after that, includes adding a magnesium salt to mix with the accompanied water under alkaline conditions to produce insoluble silica and calcium sulfate. A microfiltration (MF) membrane treatment process includes treating a first reaction solution obtained in said magnesium salt adding process, with a microfiltration membrane to separate insolubilized silica and calcium sulfate by filtration. An acid adding process includes adding an acid to and mixing with filtrate obtained in the MF membrane treatment process to render a pH value of the filtrate on the range from 5 to 9 and a negative Langeliar saturation index. A reverse osmosis membrane treatment process includes treating a second reaction solution, obtained in the acid adding process, with a reverse osmosis membrane to obtain fresh water and membrane concentrates.