| 摘要 |
PCT No. PCT/FR97/00260 Sec. 371 Date Aug. 11, 1998 Sec. 102(e) Date Aug. 11, 1998 PCT Filed Feb. 10, 1997 PCT Pub. No. WO97/29998 PCT Pub. Date Aug. 21, 1997A mixed culture reactor biologically removes organic pollution and nitrates by the anoxic route. The reactor includes a central stirred section having a lower part in which biological treatment of supplied raw water takes place. The central reactor section contains a suspension of an attached biomass of low concentration, in the order of a few grams per liter. At least one propelling screw is positioned within a jacket that is coaxially located in the reactor central section to ensure the circulation of the water to be treated. The water to be treated circulates in one direction within the jacket and in an opposite direction outside the jacket. The speed of circulation is selected so that bioparticles remain in suspension within the reactor central section. A release zone is located externally of the reactor central section and communicates with a lower part thereof. The water treated within the reactor central section escapes through the release zone, to the upper part of the central section, in accordance with an ascending current. This current has a speed such that the decantation speed of the bioparticles is greater than the speed of the water, and the speed of decantation of the excess biomass produced by biological reactions (denitrification in particular) is less than the speed of the water. Means are also included for enlarging a reactive zone at the lower part of the release zone.
|
