Abstract
The relationships between organic loading rate 3.5-8.75 kgTOC·m-3·d-1, granulation property and treatment efficiency were studied through about 600 day operation in a laboratory-scale UASB reactor at a normal temperature (20°C). The results obtained from this study were as follows : (1) In case of organic loading rate 3.5-7.0 kgTOC·m-3·d-1, maintenance of the shape of globular glanule, the increase in the median granule diameter, the increase in the ratio of white and grey granules and the increase in the bulk density of granules were obseved. After 600 days of reactor operation under these conditions, granulation property was maintained and about 87% TOC reduction was achieved ; (2) In case of organic loading rate more than 7.0 kgTOC·m-3·d-1, the shape of granule changed to on irregular type, and disintegrated at 8.75 kgTOC·m-3·d-1, the bulk density of granules were changed lighter, TOC reduction was reduced quickly.
It was made clear that the organic loading rate was a significant factor for maintenance of optimum granulation and treatment property.
