Buoyant filter media

摘要

A liquid purification system using buoyant filter media for removing suspended solids from liquid comprising a vessel having a wastewater inlet and a clarified effluent outlet. Baffles are provided in the vessel to define an upflow region for the wastewaters over a weir into a downflow region for subsequent removal by the effluent outlet. Buoyant media is provided in the upflow and downflow regions where the buoyancy of the media in the upflow region carries some of the buoyant media over into the downflow region until equilibrium is reached. A device may be provided for the continuous removal, washing and return of buoyant media to the system.