Use of a sequencing batch biofilter for degradation of azo dyes (acids andbases)

The degradation of azo dyes in an aerobic biofilter operated in an SBR syst em was studied. The azo dyes studied were Acid Red 151 and a textile efflue nt containing basic dyes (Basic Blue 41, Basic Red 46 and 16 and Basic Yell ow 28 and 19). In the case of Acid Red 151 a maximal substrate degradation rate of 288 mg AR151/l(liquid) . d was obtained and degradation efficiencie s were between 60 and 99%. Mineralization studies showed that 73% (as carbo n) of the initial azo dye was transformed to CO2 by the consortia. The text ile effluent was efficiently biodegraded by the reactor. A maximal removal rate of 2.3 kg COD/l(liquid) . d Was obtained with removal efficiencies (as COD) varying from 76 to 97%. In all the cycles the system presented 80% of colour removal.