CHARACTERISTICS OF MICROBIAL COMMUNITY RETAINED IN POROUS SUPPORT PARTICLES FOR DEGRADATION OF ORGANIC WASTE-WATER

Characteristics of microbial communities retained in polyurethane cubes of different sizes (5, 7 and 10mm) were investigated. It was found that microbial communities retained by the support particles started forming at the center of the cubes and gradually extended to the periphery. Although the development of the microbial communities depended on the support sizes, their steady-state densities were independent of support size. The results also showed that besides organic oxidation and nitrification, which occurred in all support particles, denitrification was also observed in 7- and 10-mm support particles in which an anaerobic region was presumably present. However, dentrification was scarcely observed in 5-mm support particles in which, presumably, only aerobic bacteria existed. Therefore, support particles of appropriate size make it possible to develop a microbial community capable of simultaneous removal of nitrogenous and organic substances.