DENITRIFICATION CHARACTERISTICS OF IMMOBILIZED DENITRIFYING BACTERIA

The denitrification characteristics of denitrifying bacteria immobilized by polyvinyl alcohol (PVA) were studied with different N sources and at different temperatures and NH_4~+ concentrations and compared with those of free (non-immobilized) bacteria. The optimum temperature for denitrifying liquid waste was 30℃ for both immobilized and free denitrifying bacteria. The denitrification rate of NO_2~-N was lower than that of NO_3~—N in the immobilized denitrifying process. Immobilized denitrifying bacteria were more tolerant to low temperature and high NH_4~+ than free denitrifying bacteria.