Patent ID: 9695077
Date: 2017-07-04
CPC Classifications: B01D,C02F

Claim:
1. In a wastewater treatment system, a method for converting a suction duct clarifier to a suction pipe clarifier, comprising the steps of: removing an existing sludge collection drum on the basin floor, thereby exposing a floor opening that leads to a horizontal under-floor RAS return pipe for sludge exit out of the clarifier, providing a series of sludge riser pipes on rake arms of the clarifier, positioned to collect raked sludge into the sludge riser pipes as the rake arms rotate around the clarifier, providing an elevated sludge collection box on a center/influent column of the clarifier, the elevated sludge collection box receiving upper ends of the sludge riser pipes, rotating along with the rake arms, sealed against the stationary center/influent column and having a floor positioned below the liquid level in the clarifier basin such that a liquid level of sludge in the collection box will be below the liquid level in the clarifier basin, providing a sludge discharge downpipe vertically within the center/influent column, the downpipe having an upper end adjacent to the sludge collection box and positioned to receive sludge from the sludge collection box, such that a flow path is provided for sludge from the sludge collection box into the sludge discharge downpipe to convey sludge from the collection box into the sludge discharge downpipe, isolated from influent wastewater in the center/influent column, the lower end of the sludge discharge downpipe including an elbow to turn sludge flow radially outwardly, and including securing the downpipe to a hole in a wall of the center/influent column in a sealed connection such that sludge can flow down through the sludge discharge downpipe and out through the hole in the center/influent column without mingling with influent wastewater, and installing a sludge transfer box at the bottom of the center column, sealed against the center column around the exit end of the sludge discharge downpipe, and at a bottom side of the sludge transfer box, sealed around the existing floor opening, whereby the clarifier is converted to a suction pipe clarifier without the need to penetrate the clarifier basin's floor.