The University Area Joint Authority’s (UAJA) Spring Creek Pollution Control Facility previously disinfected its wastewater discharge using an ultraviolet (UV) system. While the UV system was effective at removing viruses and bacteria, it could not remove pharmaceutical products in the wastewater effluent. UAJA desired a new system that combines disinfection and advanced oxidation to remove trace pharmaceuticals from its wastewater. Because of our previous innovative engineering experience at the facility, UAJA hired RETTEW to design, procure, and supervise the installation of the new ozonation system.

Ozone is a very strong oxidizing agent that must be handled with safety in mind. For larger ozonation systems such as UAJA’s, liquid oxygen is the feed gas to the ozone generation system. Liquid oxygen is stored under pressure at cryogenic temperatures (-297° F), requiring additional design and safety measures. Pennsylvania does not currently have regulatory guidelines for using ozone for primary disinfection of wastewater. RETTEW worked with the Pennsylvania Department of Environmental Protection for an individual case acceptance for this project.

RETTEW’s innovative design resulted in a 50 percent reduction in annual operating costs compared to the legacy UV system. Additionally, the ozonation system required $400,000 less capital expenditures compared with an upgraded UV system. The new ozonation system will also oxygenate the final effluent, allowing it to increase the dissolved oxygen content of UAJA’s wastewater effluent discharge to the local stream. Once the new system is in operation, the Spring Creek Pollution Control Facility will be one of only five wastewater treatment plants in the United States that uses ozone for primary disinfection.