Biological nutrient removal using an IACOD process: determining the combined effects of low temperature and long solids retention time.

This study was undertaken using an intermittently aerated cylindrical oxidation ditch (IACOD) process for biological nutrient removal. The kinetic aspects of nitrification, denitrification, and phosphorus release/uptake were investigated by conducting a pilot-scale operation under various contact times for the aerobic/anoxic reactor, SRTs, and HRTs. The effects of temperature were also evaluated.