Biodegradation of odor compounds by isolated bacteria with batch experiments and bench-scale continuous bioreactor.

• Main Authors: Ya-Wen Hsu, 許雅雯
• Other Authors: Ming-Muh Kao
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/22135135598202364364

碩士 === 國立成功大學 === 環境工程學系碩博士班 === 94 === Abstract The occurrence of taste and odor problems in drinking water is widespread all over the world, and often causes popular discontent for the water quality. Some physi-chemical controlled technologies have been shown to be effective in removing the taste and odor compounds from drinking water; however, the capitalized cost in installation and maintenance was higher than the biological controlled technologies. This study mainly investigated about the biodegradation efficiency of the isolated bacteria (B-1 and B-2) which might remove the taste and odor compounds from water with batch experiments and bench-scale continuous bioreactor. Furthermore, we also used the tools of molecular biology technique to identify the test bacteria and further established the phylogenetic tree. In the batch experiments, the results indicated that the degradation efficiency of removing 2-MIB by the test bacteria could reach above 98% when the additive 2-MIB concentration was equaled to 100 ng/L and the pH of culture medium was 7.0 at 35℃. We also found that the pH value of culture medium and additive 2-MIB concentration were the major factors had significant effects for degrading 2-MIB. Moreover, from the bench-scale continuous bioreactor, the results indicated that the degradation efficiencies of B-1 and B-2 were about 98.36% and 98.68% when the hydraulic retention time (HRT) was 10 h and the duration was 163 h, respectively. If the HRT was changed to 24 h, the degradation efficiencies of B-1 and B-2 were about 94.9% and 94.08%, respectively. By the way, we also discovered that the two test bacteria had the same degrading tendency for removing 2-MIB no matter the HRT was 10 or 24 h. After using the molecular biology technique to identify the test bacteria, the phylogeny results confirmed that B-1 and B-2 are belong to Bacillus genus, a branch of Bacillaceae family, and the nearest relative bacteria of them includes Bacillus sp. , Bacillus cereus, Bacillus thuringiensis and Bacillus anthracis. At last, we compared the experimental results with the references in the past, we could found that some bacteria of the Bacillus genus indeed have the ability to degrade the musty/earthy compounds in water by relying on the cometabolism or other mechanisms.