The Preliminary Study of Bio-Diatomite Dynamic Membrane for Municipal Wastewater Treatment

Bio-diatomite dynamic membrane (BDDM) is a new technology for municipal wastewater treatment. A 74 mum stainless steel mesh material was used to make the BDDM support module. The flux changes of BDDM can be divided into two stages. In the first stage, the flux declines sharply and it lasts about 30 min till the precoated process is done. In the second stage, the flux declines smoothly and the process lasts more than 400 min. Before the backwash, the average flux of BDDM is around 50 L/m².h. With water backwash presser 0.049 MPa, the flux of bio-diatomite membrane can be recovered. Except NH₄ ⁺-N which had no significant disparity, the effluent quality of BDDM was better than that from the clarifier tank, especially for turbidity and COD_Cr under the same condition of bio-diatomite reactor treatment.