| 摘要 |
A water treatment column has the space above two or more different treatment beds filled with light, small bodies, such as hollow plastic spheres or inert granular material, which restricts movement and prevents undesirable mixing of the bed materials. As treatment bed materials expand during processing, the bodies are pushed out of the inlet pipe at the top of the column against the flow of incoming water; they are held in reserve, and prevented from dispersing during backflow regeneration, and automatically return to the column head space when processing recommences. |
