Real Time Wastewater Monitoring of a Liquid Phase Odor Control Program for Improved Program Efficiency

Hydrogen sulfide is the most commonly known and prevalent odorous gas associated with domestic wastewater and is also a precursor to the formation of sulfuric acid, which can cause significant corrosive damage. Many municipalities introduce treatment products into their collection system to either prevent or remove hydrogen sulfide for odor and corrosion control. The County of Santa Cruz discharges its raw sewage to the City of Santa Cruz Wastewater Treatment Facility (WTF). The City requires the County to pretreat the incoming sewage for elevated dissolved sulfide (DS) concentrations. Previously, intermittent field tests were used to monitor incoming hydrogen sulfide levels and assure compliance. The County improved program control by utilizing an in-line analyzer to measure real-time nitrates and sulfides. The addition of this instrument has the following benefits:• Convenient, real-time data collection• Better sulfide control with real-time data for dissolved sulfides• Improved product dosing with real-time nitrate concentrations