The University Area Joint Authority’s (UAJA) Spring Creek Pollution Control Facility provides wastewater treatment, solids handling, and reuse water to the Centre Region and comprises an advanced wastewater treatment facility with tertiary effluent standards and advanced water reclamation. The facility is currently rated for 10.56 mgd hydraulically (MMAF) and 50,000 pounds/day of biochemical oxygen demand.
The facility also includes a composting process that converts wastewater treatment plant sludge and wood chips to a Class A biosolids compost product that is then sold to the local community. The existing biosolids facilities were reaching the end of their useful life and would soon require replacement and expansion. RETTEW evaluated different Class A biosolids technologies and selected a state-of-the-art anaerobic digestion process to convert UAJA’s sludge to renewable natural gas and dried biosolids.
RETTEW designed an upgrade to UAJA’s biosolids process to include:
- Sludge pre-thickening using belt thickeners
- Temperature-phased Class A anaerobic digestion
- Third-party food waste digestion
- Biogas upgrading to renewable natural gas for pipeline injection
- Thermal belt sludge dryer.
By converting the composting process to anaerobic digestion with sludge drying, UAJA will save approximately $11 million over the next 25 years through operational cost reductions and revenue generation.