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. 21, 1997
Filed:
Feb. 13, 1995
Mark Girovich, Baltimore, MD (US);
Donald Clark, Centerville, MD (US);
Bio Gro Systems, Inc., Annapolis, MD (US);
Abstract
An alkaline stabilization process for treating partially dewatered sludge while reducing lime consumption, increasing nutrient values and applicability of the product, and enhancing physical handling characteristics such as dryness, granularity and spreadability including feeding a predetermined amount of partially dewatered sludge to a first mixer, adding a predetermined amount of alkaline material to the sludge in the first mixer, mixing the sludge and alkaline material together in the first mixer to form a mixture, discharging the mixture from the first mixer, directing the mixture to a second mixer, adding a predetermined amount of end product enhancing additive to the second mixer, mixing the mixture and end product enhancing additive in the second mixer to form an end product and discharging the end product from the second mixer. The system for carrying out the process includes a first mixer, a first feeder for feeding a predetermined amount of partially dewatered sludge to the first mixer, a holding bin to retain the mixture, a second feeder for feeding a predetermined amount of alkaline material to the first mixer in sufficient quantity to heat a mixture of sludge and alkaline material to a predetermined temperature and raising the pH level of the mixture to a predetermined level, a transferring device for transferring the mixture from the first mixer, a second mixer for receiving the mixture from said transferring device, a third feeder for feeding a predetermined amount of an end product enhancing additive to the second mixer and a discharge conveyor for discharging a beneficial use end product from the second mixer.