Patent ID: 7488413
Filing Date: 2009-02-10
Classification: C02F,Y02W,Y10S

Abstract:
1. A waste water treatment plant including: a treatment chamber containing a plurality of generally buoyant sludge carrier elements, and, in a lower part thereof a bio-film collection region for receiving in use bio-film from said sludge carrier elements; an upper screen element at the upper end of said treatment chamber and a lower screen element separating the main part of the treatment chamber from the biofilm collection region, thereby to define, between said upper and lower screen elements, a containment volume within which said sludge carrier elements are confined; an outlet for delivering waste water into an upper part of said treatment chamber; a settlement chamber in flow communication at its lower end with said treatment chamber, whereby in use water may flow from said treatment chamber via said bio-film collection region to said settlement chamber; a generally vertical column passing through said treatment chamber and having an upper end which projects above the liquid surface in use, and a lower region in flow communication with said treatment chamber below said lower screen element, and air delivery means for introducing air or other gas into a lower region of said column in use to aerate the liquid therein and to cause the liquid to flow upwardly to overflow into said treatment chamber, thereby to circulate back down the treatment chamber, whereby in use the flow from said column causes movement of said sludge carrier elements up and down said containment volume, with and against the flow of said liquid.