THE STUDY OF NUTRIENT BALANCE IN SEQUENCING BATCH REACTOR WASTEWATER TREATMENT

Milenko Roš* and Janez Vrtovšek
National Institute of Chemistry, PO BOX 660, Hajdrihova 19, SI-1001 Ljubljana, Slovenia

Abstract
The Sequencing Batch Reactor (SBR) is very suitable system for combined wastewater treatment of organic compounds and nutrient removal. Reactor can work at different conditions such as anaerobic, anoxic or aerobic. The objective of our research work was to study the influence of phosphorus concentration on N removal in a SBR wastewater treatment at various COD:N:P ratios. The results showed that the removal of N was not dependent on initial P concentration, but P removal was related to P concentration in the original wastewater. All experiments were carried out with synthetic wastewater to which different amounts of P were added. The optimal COD:N:P ratio was 100:11:2 and the BOD5:N:P ratio was 100:15:2.6.

Key words: biological wastewater treatment, nutrient removal, SBR, C:N:P ratio