| 摘要 |
<p>The waste water is percolated through an aerated, biological filter bed contg. mineral or plastic particles. To improve oxygenation of the waste water, pressure within the bed is then retained at a level slightly below atmospheric, pref. 0.981 to 0.99 atmos. The bed is pref. contained in a vertical, cylindrical, contacting column with an air inlet at one end and connection to a vacuum pump at the other end. Alternatively, the bed can be contained in a rotary drum, slightly inclined to the horizontal and fitted with similar air inlet and suction connection. Partic. high efficiency is obtd., due to the introduction of O2 at a higher rate than is possible by natural air circulation thro. a percolating bed or by an activated sludge process.</p> |
