割り箸を有機炭素源とした脱窒処理における硫酸塩還元細菌および硫黄脱窒細菌の役割

抄録

Denitrification using chopsticks as organic carbon source was examined in an anaerobic-anoxic biological filter reactor and an anoxic biological filter reactor. In the two phase anaerobic-anoxic reactor, sulfate reduction and acetate production occurred in the anaerobic bed packed with chopsticks. In the anoxic bed connected to the anaerobic bed with chopsticks, sulfur denitrification and heterotrophic denitrification occurred. In the single anoxic biological filter reactor, denitrification and sulfate reduction occurred simultaneously in the anoxic bed packed with chopsticks. The sulfate reducing activities of the biofilm in both reactors packed with chopsticks were high, meaning that sulfate reduction played an important role on decomposition of chopsticks. Microbial community of sulfate reducing bacteria and sulfur oxidation bacteria was examined by a FISH method. Desulfobulbus spp., Desulfbbactor spp. and Desulfonema spp. were most common sulfate reducing bacteria grown in the anaerobic bed of the two phase reactor and the anoxic bed of the single reactor. Thiobacillus denitrificans was also observed in the anoxic biofilm with the chopsticks of the single reactor. It was observed that Desulfonema spp. was attached with Thiothrix nivea, and sulfur oxidation-reduction cycle was established in the biofilm under anoxic condition.