Process for anaerobic treatment of residual streams, in particular of acidic aqueous effluents from petrochemistry

摘要

Residual streams, in particular acidic aqueous effluents from petrochemistry, are treated in an anaerobic filter 5, under high loads, with high recycling flow rates. The effluent originating from the filter passes through a zone 13 for release of the gases and sedimentation of the solids, containing a volume 14 at rest of the liquid of the said effluent. The particles of solid biomass deposit in the volume of liquid and are withdrawn, with the liquid, and recycled to the base of the filter with a fresh charge of the acidic residual stream and an added inorganic alkaline material. The discharge from the filter is conveyed to an anaerobic digester 31 and the activated sludge resulting therefrom is recycled into the filter 5. The alkaline material is preferably magnesium oxide or carbonate. Sodium formate can also be employed as alkaline material. IMAGE