St. Cloud Wastewater Treatment Facility (WWTF) Nutrient Harvesting Pilot Project

The St. Cloud Waste Water Treatment Facility (SCWWTF) is currently conducting long term planning for future biosolids management. The most likely path forward includes dewatering of the digested biosolids, which will produce a supernatant stream with significant phosphorus and ammonia loads that would be returned to the liquids treatment portion of the WWTF. Returning these nutrient loads to the liquids train would result in increases to effluent concentrations, increases in power consumption, or both.

The SCWWTF will collect and analyze the nutrient stream in order to develop a mass balance of phosphorus throughout the system. The results will be used to determine the successful return of nutrient reduced supernatant such that liquid effluent discharge to the receiving waters will not be compromised. It is hypothesized that results will be transferable to similar treatment facilities.