Biological clearing device

摘要

The biological calrification device (10) comprises a pre-clarification chamber (12), a clarification chamber (14), and devices intended for conveying and treating wastewater and comprising an aerator (24) arranged in the clarification chamber, a pressure source (26) for a pressurized liquid, a pressure pipeline (29) guiding from the pressure source to the aerator and a sludge lifter for recirculating the sludge from the clarification chamber into the pre-clarification chamber. The sludge lifter is connected to the pressure pipeline over an arm coming out from the pressure pipeline. The biological calrification device (10) comprises a pre-clarification chamber (12), a clarification chamber (14), and devices intended for conveying and treating wastewater and comprising an aerator (24) arranged in the clarification chamber, a pressure source (26) for a pressurized liquid, a pressure pipeline (29) guiding from the pressure source to the aerator and a sludge lifter for recirculating the sludge from the clarification chamber into the pre-clarification chamber. The sludge lifter is connected to the pressure pipeline over an arm coming out from the pressure pipeline and comprises an ascending tube section, in which an upper valve body is present with a density larger than that of the wastewater. A lower end of the ascending tube section is connected to the arm and the ascending tube section has a valve seat for the upper valve body at its upper end. A lower valve is connected to the lower end of the ascending tube section for connecting the inner area of the sludge lifter with the environment and is lockable from inside by pressurization of the sludge lifter. A descending tube section, in which a lower valve body is present with a density larger than that of the wastewater, is connected to the lower end of the ascending tube section and has a further valve seat for the lower valve body at its lower end. The ascending tube section has a block for the upper valve body at its lower end and the descending tube section has the block for the lower valve body at its upper end. The ascending and descending tube sections form two sections of a vertical tube connected to each other. The common block for the valve bodies is provided at the connecting point of the tube sections. The lower end of the descending tube section is arranged in a predetermined height over the bottom of the clarification chamber. One of a first section of the pressure pipeline coming out from the pressure source flows into an inlet of a T-piece, which has two discharge openings. A first discharge opening is connected to the aerator over a second section of the pressure pipeline and a second discharge opening is connected to the sludge lifter over the arm. The pressure source is a compressor for admitting the aerator with a compressed air. The pressure source is a pump for conveying water towards the aerator. An air suction line flows into the pressure pipeline for sucking air during operating the pump.