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:
Jul. 31, 2001
Filed:
Jul. 01, 1999
Keiji Uemura, Tokyo, JP;
Hirotake Shigemi, Tokyo, JP;
Kurita Water Industries Ltd., Tokyo, JP;
Abstract
A spiral wound type membrane module is formed of a plurality of membranes wound about an axis of the module to form a roll of the membranes and to form feed water channels between the membranes into which feed water flows via a front end of the roll and from which nonpermeated water flows out via a rear end of the roll, wherein the module is operated such that a differential pressure between the feed water flowing into the channels and the nonpermeated water flowing out from the channels is 0.3 kg/cm,or less. The pressure of the feed water is kept at P,or an approximate value of P,which brings a maximum permeate flux at the moment when a predetermined period has passed after starting to supply the feed water into the membrane module continuously at a constant pressure.