Process and assembly to treat waste water by de-coupling sludge ozone treatment from the biological treatment stage

摘要

In a waste water treatment process the water is first subject to a biological treatment stage (1) followed by sedimentation (2) and transfer of excess sludge to an ozone treatment stage. The ozone-treated sludge (7) is not returned to the biological treatment stage. An independent claim is also included for a waste water treatment assembly in which the aerobic or ozone treatment is repeated is repeated several times for about 2 minutes, followed by discharge to a thickening stage and removal of water (8). The ozone treatment is at the rate of about 0.002 g ozone per gram dry matter.