| 摘要 |
<p>in an installation for aerating activated sewage sludge separate arrays (5, 6) of two different types of diffuser are provided, the air supply to each array being under independent control of a control system. The first type of diffuser (7) is fixed and the corresponding array (5) is fed with a continuous (but possibly variable-quantity) supply of air. The second type of diffuser (8) has a flexible membrane which constitutes a non-return valve and the air supply to the corresponding array (6) is controlled according to the aeration requirements of the sludge. The system for controlling the air supply includes a dissolved oxygen sensor. The control system may be a computer-based export system to tailor the system performance to the specific installation. <IMAGE></p> |
