| 摘要 |
<p>The invention relates to a process and an apparatus for the biological purification of water, in a floating-grain filter through which flow passes from bottom to top and in which floating grain is separated by a sieve plate from clean water collecting thereabove, the untreated water being supplied with gas necessary for the biological purification and floating grain fouled by the biological purification being washed, impurities separated off during the washing of floating grain being collected in a sludge thickener formed at the lower end of the floating-grain filter. In continuous biofiltration of the untreated water, the floating grain is circulated by continuously taking off a part of the clean water with a floating-grain portion and introducing it into the feed for untreated water with washing of the entrained floating-grain portion.</p> |
