生物活性炭による低濃度有機化合物の分解除去

Abstract

Biodegradation of organic substances by attached bacteria on biological activated carbon (BAC) was studied to clarify the advantages of granular activated carbon (GAC) as a support medium over conventional medium without adsorption capacity with regard to biodegradation activity and community structure of attached bacteria. Anthracite (AN) was used as a reference support medium without adsorbability. Low molecular organic substances with different biodegradability and adsorbability (phenol, benzoic acid, glucose and m-aminobenzoic acid) were fed into completely mixed BAC and AN reactors. The rates of biodegradation by BAC reactors fed with the biodegradable organic substances were approximately 3 times as high as those by AN reactors. The difference in adsorbability of the organic substances onto GAC had little effect on the rate of biodegradation. m-Aminobenzoic acid with low biodegradability was degraded only by the BAC reactor. The structure of GAC with micro and macro pores did not provide better habitat for attached bacteria with regard to the size of population in comparison with AN without pores. Bacterial floras on GAC was probably little difference from those on anthracite. Therefore GAC as a bacterial support medium stimulated the biodegradation activity of each bacterium without increase in the population and probably with little change in the species composition.