关键词: 微生物燃料电池, 厌氧流化床, 床层膨胀高度, 功率密度, 阴极位置

Abstract: Anaerobic fluidized bed microbial fuel cell (MFC) with 40 mm in diameter and 600 mm in height was employed to investigate the effect of fluidization bed expansion on the electrogenesis capacity of MFC. Three different cathodes were investigated for cathode positions at 150, 250 and 350 mm above distributor. When the expansion height was less than 170 mm, the electrogenesis capacity at cathode 1 was the maximum, up to 347.1 mW/m2. The power density decreased with decreasing cathode position along the bed height. When the expansion height ranged from 170 to 270 mm. The electrogenesis capacity at cathode 2 was larger than that at cathodes 1 and 3, which approached 361.0 mW/m2 when the flow rate of wastewater was kept at 8.35 mm/s. When the expansion height of fluidization bed was 270 to 400 mm, the electrogenesis capacity of three cathodes was all decreased. However, cathode 3 had a minimum decline value, 297.5 mW/m2 at the flow rate of wastewater of 10.61 mm/s. The power density increased with increasing cathode position along the bed height. The results were due to the effects of the flow rate on the mass and electron transport efficiency in anode chamber, and the effects of the flow rate on the growth of microbial film.

Key words: microbial fuel cell, anaerobic fluidized bed, bed expansion height, power density, cathode position