VERFAHREN UND VORRICHTUNG FUER ABWASSERREINIGUNG IN EINEM BIOLOGISCHEN FILTER MIT PARTIKELN, DIE WENIGER DICHT ALS WASSER SIND.

摘要

According to the process where the water to be treated (11) and the oxygen-containing gas (3) are directed in rising streams into a single reactor (1) or biological filter provided with expanded plastic or inorganic particles which are lighter than water, the filter medium consists essentially of a lower layer (4) of a fluidised bed of particles and then of an upper layer (5) of a stationary bed of smaller and lighter particles. A support layer of particles of low density and of coarser particle size may be provided between the upper bed (5) and the perforated retaining device or ceiling (7). Application to the treatment of water to be purified and of water to be made drinkable.