Small scale domestic effluent treatment for up to 600 inhabitants

摘要

The treatment vessel is divided into two equal parts. Effluent for treatment is supplied to each vessel for periods of 24 hours, during which the vessel is aerated (29) from its base (3) with fine bubbles, and the effluent degraded by micro-organisms supported on vertical sheets (23) submerged in the liquid. During the next 24 hour period clarified effluent (40) and excess sludge are removed. The vertical sheets holding the micro-organisms are positioned 25 to 30 cm apart from each other and are submerged by at least 20 cm. Aeration is carried out intermittently during both filling and emptying periods. During emptying aeration is followed by settling, then skimming liquid from near the surface.