Patent ID: 6348147
Filing Date: 2002-02-19
Classification: C02F,Y02W

Abstract:
A biological contactor using aerobic bacteria growth media confined in a submerged region of a container supported by a float in a wastewater treatment lagoon, the contactor comprising:a. the container holding the media having a bottom provided with openings small enough to prevent the media from falling downward through the openings and large enough to allow liquid from the lagoon to flow upward through the openings and upward through the submerged media; b. walls of the container above the bottom having openings allowing liquid flowing upward through the media to flow out through the walls and into the lagoon; c. the bottom openings allowing downward settlement of solid particles dislodged from the media so that the solid particles can fall through the bottom openings and settle to a bottom of the lagoon; d. fine bubble air diffusers arranged under the media in the region of the container bottom to emit air bubbles that rise through the media and thereby cause an upflow of a mixture of air bubbles and liquid drawn upward from below the container through the bottom openings so that the liquid and air bubbles rise up through the media within the container before the liquid flows out through the container walls and back into the lagoon; and e. coarse bubble dispensers arranged under the media in a region of the container bottom to emit coarse bubbles that rise up through the media causing sufficient turbulence to agitate the media and dislodge the solid particles from the media during a cleaning cycle.