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:
Oct. 16, 2001
Filed:
Oct. 25, 1999
Pierre Cote, Dundas, CA;
Hamid Rabie, Mississauga, CA;
Steven Pederson, Burlington, CA;
Nicholas Adams, Hamilton, CA;
Zenon Environmental Inc., Oakville, CA;
Abstract
A filtration process for filtering water with immersed microfiltration or ultrafiltration membranes in a batch mode includes repeated cycles comprising the steps of filling the tank to a level above the membranes, withdrawing permeate through the membranes, aerating the membranes to dislodge solids from the membranes and backwashing the membranes while draining the tank. The backwashing steps involve backwashings with a cleaning chemical interspersed with backwashings with permeate. The backwashings with a cleaning chemical follow a regimen of maintenance cleaning chosen to maintain acceptable permeability of the membranes or to reduce the rate of decline in permeability of membranes,over extended periods of time.