Purification treatment of a liquid waste

A process for purification of foul liquid waste material comprising introducing a mixture of human body waste materials and miscellaneous liquid waste material into a sedimentation tank, causing relatively heavy material to settle within the tank and converting said heavy material into a sludge through anaerobic activity, introducing supernatant foul liquid waste from said sedimentation tank into a submerged bioaeration-beds tank, causing said supernatant foul liquid waste to successively flow in one general horizontal direction, then to flow downwardly vertically, and then to flow in an opposite general horizontal direction in serpentine fashion, said alternate horizontal and vertical flow being effected by positioning in said bioaeration-beds tank a plurality of generally horizontally disposed and alternately foreshortened irrigated sheets in superimposed spaced array, returning foul liquid waste from the bottom of the bioaeration-beds tank to the upper region thereof by an oxygen-containing medium, causing said returned foul liquid waste and said supernatant foul liquid waste to flow together and successively flow on and between said horizontally disposed irrigated sheets, whereby the horizontally and downwardly flowing foul liquid waste is purified by the activity of aerobic micro-organisms in biomembranes formed on said generally horizontally disposed irrigated sheets, and recovering purified liquid from said bioaeration-beds tank.