Abstract: A method for wastewater treatment, in a continuous flow system, and a plant for wastewater treatment, to achieve high level reduction of biogenic nitrate compounds are provided. Subjecting a mixture of active sludge and wastewater to vacuum degassing on the mixture that has been subject to earlier nitrification, but not introduced in a recirculation-return connection, and constituting the outflow from a nitrification volume, before degassing, is subject to additional denitrification. The mixture of active sludge and wastewater, due to the additional denitrification step, may be free of carbon carried along with wastewater. An external source of readily available carbon is introduced, and further deepened nitrates removal is performed. After wastewater is degassed, treatment continues within a gaseous nitrogen undersaturated aqueous zone of a secondary sedimentation tank.

Abstract: A method for wastewater treatment, in a continuous flow system, and a plant for wastewater treatment, to achieve high level reduction of biogenic nitrate compounds are provided. Subjecting a mixture of active sludge and wastewater to vacuum degassing on the mixture that has been subject to earlier nitrification, but not introduced in a recirculation-return connection, and constituting the outflow from a nitrification volume, before degassing, is subject to additional denitrification. The mixture of active sludge and wastewater, due to the additional denitrification step, may be free of carbon carried along with wastewater. An external source of readily available carbon is introduced, and further deepened nitrates removal is performed. After wastewater is degassed, treatment continues within a gaseous nitrogen undersaturated aqueous zone of a secondary sedimentation tank.

Abstract: A waste water purification process, in particular a continuous waste water purification process is disclosed, as well as a waste water purification plant system, in particular for continuous waste water purification. Waste water is purified in that an aerated mixture of waste water with activated sludge is degassed before being discharged into the secondary settling basin. The waste water purification system has a venting device that connects the aerating container or a separate chamber thereof to the secondary settling basin or a separated chamber thereof. The venting device is designed as a U-shaped tube. One of its branches forms the supply collecting pipe and the second branch forms the discharge collecting pipe, whereas the section that interconnects its two top ends delimits the intermediate chamber that contains a separate gas suction chamber.