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:
Feb. 12, 2008
Filed:
Sep. 30, 2005
John R. Mcwhirter, Boalsburg, PA (US);
Prakash G. Balan, Dunn Loring, VA (US);
Bradley A. Swope, State College, PA (US);
John R. McWhirter, Boalsburg, PA (US);
Prakash G. Balan, Dunn Loring, VA (US);
Bradley A. Swope, State College, PA (US);
Mixing and Mass Transfer Technologies, LLC, Boalsburg, PA (US);
Abstract
A continuous flow multistage aerobic wastewater sludge digestion system comprising at least two stages connected in series, each stage comprising one or more covered tanks, tank segments or compartments, each having an enclosed separate gas headspace, wherein the gas headspaces of each stage are connected in a specified sequence that may be identical to or different from the staging sequence followed by the sludge liquid. An oxygen containing gas stream, such as air or an oxygen enriched gas stream, is supplied to the headspace of each stage, and a means for aerating the sludge in one or more of the tanks, tank segments or compartments is provided to enhance the transfer of oxygen from the gas headspace into the sludge liquid for use by bacteria in digestion of the sludge. At least one stage of the sludge digestion system is operated at a thermophilic temperature above 50° C. and the flow of oxygen containing gas through the system can be co-current, countercurrent, or a mixture of both with respect to the flow of the liquid. Preferred embodiments of the invention include the use of this aerobic digestion system prior to anaerobic digestion.