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:
Jan. 07, 1992
Filed:
May. 17, 1990
Milos Krofta, Lenox, MA (US);
Lenox Institute for Research, Inc., Lenox, MA (US);
Abstract
Water clarifying apparatus has a cylindrical tank where particulate contaminants suspended in raw water are separated using flotation techniques. The treatment capacity of such a unit is increased several times, with no decrease in the size of the tank, by using a set of concentric, mutually spaced, conical plates positioned in the flotation tank. The increase is proportional to the combined area of the plates when projected onto a horizontal plane, the overlap of the projection producing an area which is greater than that of the horizontal plane without plates. The plates rotate about the tank, preferably in unison with a (i) header that distributes equal quantities of raw water to each annular zone in the tank defined by the conical plates and (ii) a scoop for removing the contaminants which form a floated sludge layer. To accommodate this increased clarification capacity the clarifying apparatus also includes (1) a screw conveyor located in a discharge pipe of the floated sludge scoop, (2) an infrared sludge detection array operating in conjunction with a window in the side wall of the tank to sense the sludge-water interface and the turbidity of the water below the interface, and in response thereto, to coordinate and control the operation of the apparatus, and (3) air dissolving tubes operating in parallel that have common feeds and discharges coupled through three way valves operated to pressurize a closed volume of water with high pressure air in one tube while reloading and discharging the other tube. Where a sandbed filter is used at the bottom of the tank, the apparatus also includes clarified water extraction pipes imbedded in the sand and a steam backwashing system.