公开(公告)号：WO2022200895A2

公开(公告)日：2022-09-29

申请号：PCT/IB2022/052069

申请日：2022-03-08

申请人： TALLINN UNIVERSITY OF TECHNOLOGY

发明人： SOKK, Olev ,  PACHEL, Karin ,  KUUSIK, Argo

IPC分类号： C02F3/30 ,  C02F3/06 ,  C02F101/10 ,  C02F101/16 ,  C02F101/32 ,  C02F2101/105 ,  C02F2101/16 ,  C02F2101/32 ,  C02F3/308

摘要： Method for biological removal of nitrogen, phosphorus and organic pollutants from wastewater in a multistage submerged biofilm device, which is mainly intended for the treatment of moderate quantities of wastewater in rural areas. The wastewater inflow is directed into a first zone of the first stage operated in anaerobic conditions and after that it is directed into a second zone of the first stage operated in aerobic conditions. After a certain time the wastewater inflow to the first zone is stopped and it is directed to the second zone where at same time the operating conditions of the first and second zone are inverted (first zone previously operated anaerobically becomes aerobic and second zone becomes anaerobic). Such alternating process is continued. At the outlet of the first stage the wastewater is directed to an intermediate settle tank and then to a second aerobic stage with submerged biofilm. From the second stage the wastewater flows to the third stage with anoxic submerged biofilm and then to the final clarifier. Settled sludge from intermediate settle tank and final clarifier is directed into anaerobic part of Imhoff tank (Emscher tank) which overflow can be sent upstream the third stage is available. Settled sludge stabilisation after anaerobic stage is finished in aerobic stage of the Imhoff tank.