An Anaerobic Fixed Bed Reactor with a Porous Ceramic Carrier

To date, a large number of studies on anaerobic fixed bed reactors have been reported, but there have been few studies on the application of this technology to thermophilic anaerobic treatment. One of the reasons for the small number of applications is the difficulty of attaching thermophilic anaerobic organisms to carriers. The study reported in this paper was conducted to examine the thermophilic treatment performance of an anaerobic fixed bed reactor containing a porous ceramic carrier (‘microbe immobilized ceramic', MIC) developed for the immobilization of anaerobic organisms. When boiled soybean wastewater (55,000 mg/l COD) was treated anaerobically at a high temperature (54°C) in a reactor where 31% of the volume was filled with the MIC carrier, it was found that highly loaded operation with up to 65 kg COD/m³/d was possible. The COD load per unit area of carrier surface under these operational conditions reached 0.397 kg COD/m³/d, and the performance of the reactor was excellent. Stable anaerobic treatment was achieved when the COD loading rate fluctuated from 26 to 51 kg COD/m³/d.