a performance study of simultaneous microbial removal of no and so2 in a biotrickling-filter under anaerobic condition

behaviors of simultaneous removal of no and so2 using the coculture of anaerobic denitrifying bacteria and sulfate reducing bacteria were investigated in a bench-scale biotrickling-filter. approximate 20 days were required to use the landfill leachate as the microbial seed to develop the biofilm on the surface of packing material. when the combined no/so2 removal biotrickling-filter was operated at an empty bed residence time (ebrt) of 76 s and the no and so2 feed concentrations of 2 and 2 g/m3 respectively, the so2 removal efficiency was always above 95%, while no removal exhibited an evident periodicity of 5-6 days for the initial 60 days after the attachment phase and then a steady-state no-removal efficiency of around 90% was obtained after 130 days of continuous operation. contrast experimental results indicated that the coculture in the combined no/so2 removal biotrickling-filter showed a higher resistance to shock no-loadings and a better tolerance of starvation than the single denitrifying bacteria in the no removal biotrickling-filter.