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:
Apr. 08, 1997
Filed:
Mar. 12, 1996
Applicant:
Inventors:
Assignee:
Best Industries, Inc., Osaka-fu, JP;
Primary Examiner:
Int. Cl.
CPC ...
C02F / ;
U.S. Cl.
CPC ...
210618 ; 210794 ;
Abstract
A method of preparing and cleaning a floating filter medium for a biological cleaning apparatus includes the steps of forming a filter layer by placing in a treating tank a granular floating filter medium having a specific gravity of about 0.3 or less and a particle size of 1 to 15 mm. Wastewater enters the tank and flows through the filter layer. Excess sludge is separated and removed from the filter medium by discharging an amount of water from the treating tank, from below the filtered layer, equivalent to 0.5 to 1.5 times the filling amount of the filter medium in a time period of between 5 to 90 seconds.