Research on Immobilized Ammonia-Oxidizing Bacteria by Sodium Alginate

Ammonia-oxidizing bacteria were immobilized by sodium alginate. Immobilized conditions and ammonium removal ability of immobilized cells were researched. The results showed that the optimal immobilized conditions were: 4.5% sodium alginate with 2.0% calcium chloride, 2000 immobilized balls, 1000mL immobilized medium, pH 8, 30°C, 110r/min. Immobilized ammonia-oxidizing bacteria were recycled six times under the optimal immobilized conditions. Immobilized ammonia-oxidizing bacteria at the optimal conditions had better ammonium removal ability than non-immobilized ammonia-oxidizing and were good for preservation. Removal rate of ammonia nitrogen of immobilized ammonia-oxidizing bacteria reached 89.51%.