| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for treating biological waste water by adding a carrier without comprehensively immobilizing microorganisms thereon to a biological treatment tank and allowing the carrier to flow and forming a microorganism supporting carrier having high settleability. <P>SOLUTION: In the method, a gel carrier 35 such as polyacrylic acid or the like is added to a reaction zone 11 in a treatment tank 10. An effluent from the reaction zone 11 is subjected to solid-liquid separation in a separation zone 12. The carrier 35 is allowed to flow intensely by aerating the reaction zone 11 at a rate of 0.03 m/s or higher, or at the same time, by passing water through the treatment tank 10 in such a way that LV in the separation zone 12 is 2 m/hr or higher, whereby the carrier 35 is allowed to support microorganisms in a high density and a rigid granular carrier supporting microorganisms excellent in settleability is obtained. The carrier 35 allowed to flow by air diffusion from an aeration tube 16 settles gravitationally in the separation zone 12, accumulates in the bottom of the treatment tank 10, and is returned through an opening under a partition plate 15 to the reaction zone 11 communicating with the separation zone 12. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
