Depollution procedure for fluid, especially water, containing organic micropollutants uses rising flow reactor containing activated carbon bed

摘要

The procedure uses a rising flow reactor (1) into which the fluid (2) is injected at the lower end, rising through a gravel and sand filter bed (3) and then an activated carbon bed (4), which is expanded by the flow and then drops back by gravity, while the clear fluid is recuperated at the top. The grain size of the active carbon and the speed of the rising flow are selected so as to obtain a dense suspension of the expanded active carbon in the form of a mobile bed with a depth of clear decanted fluid above it. The concentration of the carbon particles is preferably 100 - 300 g/l for the height of the expanded bed and less than 2 mg/l at the top of the clear fluid zone above it. The active carbon grain size is preferably 200 - 600 mcm, and the speed of the rising flow between 8 and 15 cu m/sq m per hour, giving a preferable contact time of 8 - 15 minutes.