Patent ID: 7147781
Filing Date: 2006-12-12
Classification: C02F,Y02W

Abstract:
1. A backwash system for a waste treatment system, comprising:— a tank; a waste inlet duct extending into a lower region of the tank; an accumulation of microbial growth media particles in the lower region of the tank; a vertical duct extending from the lower region of the tank and having a duct outlet in an upper region of the tank; a downwardly convergent strainer extending around the vertical duct beneath the duct outlet, the strainer having liquid leakage openings in the strainer: a liquid collector beneath the liquid leakage openings; a liquid outlet from the liquid collector communicating with the exterior of the tank; a solids return duct having an upper end opening through the downwardly convergent strainer and a lower end opening above the accumulation of microbial growth media particles; and an air inlet duct communicating with the vertical duct at the lower region of the tank.