Patent EP-1864707-A1 (EP)
Inventor: KOLB FRANK REINER
IPC: B01D21/24
Filed: 2007-06-06
Abstract: The sedimentation tank for a suspension of activated sludge and/or wastewater sludge, comprises a feed mechanism for feeding the suspension to be clarified, a discharge opening (5) of feed mechanism, an adjustment mechanism for alteration of the elevation of the opening in the tank and/or the exit cross-section of the opening, and a subcomponent mounted to other subcomponent in freely movable and/or displaceable manner. The elevation and/or the exit cross-section of the opening are adjustable. The adjustment mechanism is a part of a feed mechanism, which is designed as a two-component device. The sedimentation tank for a suspension of activated sludge and/or wastewater sludge, comprises a feed mechanism for feeding the suspension to be clarified, a discharge opening (5) of feed mechanism, an adjustment mechanism for alteration of the elevation of the opening in the tank and/or the exit cross-section of the opening, and a subcomponent mounted to other subcomponent in freely movable and/or displaceable manner. The elevation and/or the exit cross-section of the opening are adjustable. The adjustment mechanism is a part of a feed mechanism, which is designed as a two-component device. The actuation of the adjustment mechanism takes place by the suspension flowing into the tank and/or the adjustment mechanism is actuated in a lifting or floating and/or lowering or sinking mode. The adjustment mechanism has a flow deflection device for redirecting the flow direction of the inflowing suspension, a torque conversion mechanism, with which a portion of the flow pressure of the inflowing suspension is converted into a torque for the actuation of the adjustment mechanism, a floating and/or displacing mechanism by which a buoyant force and/or sedimentation force is exerted on the feed mechanism for the adjustment of the opening, and a shutter that is assigned to the opening and that is adjusted depending on the volume flow of the inflowing suspension. The flow deflection device is arranged at a displaceably-mounted subcomponent and/or is an integral part of the feed mechanism. The subcomponent of the feed mechanism is mounted with a vertically moving part. The average density of the subcomponent lies between the density of the liquid and solids separated from the suspension. The feed mechanism forms a chamber or a container for the temporary storage of the inflowing suspension. The subcomponent of the chamber or the container is mounted in a freely movable manner. The subcomponent is surrounded by the substances at the side that is turned away from the inflowing suspension and/or lies partially below the liquid level in the tank. The substances are held in the tank. The floating and/or displacing mechanism partly floats on the surface of the liquid in the tank and is arranged in an inlet mechanism that is arranged upstream of the tank and/or in a discharge mechanism that is arranged downstream of the tank. The elevation of the opening is adjusted by adjustment device in a range between clear water zone (24) and sludge zone, between the clear water zones in clarification zone or between storage areas (25) and in the lower part of the clarification zone. The opening with a variable exit cross-section is built between stationary and movable parts of the chamber. The opening is a gap with a variable gap width. The chamber is partly submerged under the surface of the liquid and in the surrounding substances that is held in the tank. A float is mounted, whose elevation is partly dependent on the density distribution along the elevation of the substances in the tank. The mean density of the float between the density of the liquid and solids is 1.1-1.8 times of the density of water. A portion of the adjusting device is linked or connected with the mobile part of the feed mechanism over a step-up or step-down drive mechanism. A mixing chamber (18) is arranged upstream and/or downstream to a centrally built chamber, is integrated into the feed mechanism, and is divided into several vertical and/or horizontal guidance segments that are arranged with one another such a way that a meander-shaped flow of the liquid or suspension carried out through the mixing chamber. The feed mechanism is made from a metallic outer layer with a plastic inner layer, whose average density is smaller than or equal to the density of the surrounding fluid or suspension and/or whose surfaces are coated and/or doped with a biocide-active substance and/or adhesion-minimizing substance. A cross-sectional profile of the opening is circular, jaw-shaped, ovate, elliptic or square-shaped. The average material density of a part of the subcomponent is smaller than or equal to 1000 kg/m2>. The elevation adjustment and/or adjustment of the exit cross-section takes place along a direction by actuation of the adjusting device and along the opposite direction due to the effect of gravity on the adjusting device and/or on the feed mechanism and/or by a spring component. The feed mechanism has a flow guidance component that horizontally discharges a part of the suspension flowing into the tank through the opening and/or produces a downward flow above the centre of the suspension flowing into the tank. The feed mechanism forms a rotating chamber or a ring chamber that rotates in segment-wise manner. The flow deflection device is immovably mounted at a firmly mounted subcomponent or is immovably installed in the tank and directs the suspension flow on to a subcomponent and/or the flow deflection device is arranged at the subcomponent and the suspension flow is directed on to a fixed subcomponent or through the opening. An independent claim is included for a procedure for adjusting the outlet cross-sections and or the height of a discharge opening of a feed mechanism in a sedimentation tank for the separation of a suspension.