MODEL-BASED AERATION SYSTEMS DESIGN - CASE STUDY NANSEMOND WWTP

摘要

A simulation project was conducted for HRSD’s Nansemond WWTP to evaluate the savingspotentials for different aeration control strategies based on ammonia and DO measurements.Special emphasis was put on modeling and analyzing plant constraints including blowerminimum and maximum capacities, diffuser specifications, and mixing requirements.The results show significant savings potential with ammonia- and/or DO-based aeration controlstrategies. Detailed modeling of the air distribution system allowed the design of a controlconcept tailored to the Nansemond plant. Feed-forward ammonia control was only active at lowtemperature (12 ℃) and did not significantly lower effluent ammonia peaks. Therefore feedforwardcontrol was not selected for full-scale implementation as it could not justify additionalinvestment and O&M costs against improved effluent quality or reduced risk.