BIOLOGICAL AERATED FILTERS - AN ATTRACTIVE AND ALTERNATIVE BIOLOGICAL PROCESS

Biological aerated filters are a new stage in the intensification of biological sewage treatment processes. They complete the existing range of processes, especially when site constraints make implementation of conventional processes difficult. A technical evaluation of eight full scale plants (4 upflow processes and 4 downflow processes) has been realized resulting in about a hundred data days. They showed the production of an excellent effluent quality for specific loads below 6 kg COD/m3. day. This process revealed insensitive to load shocks. Specific sludge production and specific energy consumption are comparable to those of conventional activated sludge processes.