Biological Aerated Filters: An Adapted Biological Process for Wastewater from Coastal Areas
SUMMARY compact facilities together with modular and environment-friendly appearance are arguments in favour of Biological Aerated Filters(B. A. F. ) in coastal areas where the amount of available land imposes strict limitations on technological choices. The operation of B. A. F. in combination with a physico-chemical process was studied using the data obtained from two wastewater treatment plants located in coastal areas (Barcares and Saint Palais/Mer, France). The main conclusions are the following.-Effluent quality in terms of COD, BOD5 S.S. proved satisfactory for organic load conditions higher than those applied when using conventional procedures.-Adaptation to organic load variations is not a basic problem for this type of coastal community,but hydraulic flow-rate control should be the main concern.-Restarting plant operation after a long shutdown only takes a few days.-Furthermore technical and economical optimisation required continuous monitoring, especially in the field of washing and aerating control. This type of management involves the use of reliable, high- performance control equipment.