Florence Wastewater Treatment Facility Optimizes Biosolids Composting
In 2009, the City of Florence, under the direction of City Public Works Director Mike Miller, commissioned a study to explore treatment methods that could provide value-added processing for the town’s biosolids.
PROJECT DETAILS
Ownership: City of Florence, Oregon
Location: Florence, Oregon
Start-Up: Demonstration Project: 2010 – Phase I: 2012 – Phase II: 2016
Product: SG MOBILE® System
Input quantity: 200 tons per batch (100 tons per heap)
No. of Heaps: 2 Heaps, 50 ft. x 20 ft. x 9 ft. each
Treatment Time: 8 weeks in 3 phases
Aeration: In-ground (previously above ground)
Control Parameters: Oxygen Control Mode
Input material: Biosolids
Equipment: Alu Front-end mixer for bobcat; Front-end loader; Rock Screen
End Product: High-quality Finished Compost, FloGro Compost
SG SOLUTION: Pilot-Scale Composting Proves Cost-Effective for Class A Biosolids
To evaluate cost-effective composting technologies for biosolids management, the City of Florence launched a pilot demonstration project in 2010 using the SG MOBILE® System. After comparing various composting methods, the City selected this system due to its modular design, no permanent construction requirements, or hard-wired infrastructure.
The pilot successfully demonstrated the system’s ability to:
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Produce Class A biosolids compost
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Meet the EPA Rule 503 pathogen reduction and Vector Attraction Reduction (VAR) standards
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Deliver high performance at a lower capital investment
Following the successful pilot, the City was awarded a $100,000 Waste Diversion Opportunity Grant from Lane County in 2012 to develop a small-scale biosolids composting facility. Sustainable Generation, LLC was selected to supply a permanent SG MOBILE® System with above-ground aeration.
Installed in winter 2012, the system now enables the Florence Wastewater Treatment Facility to process up to 600 tons of biosolids annually into high-quality, Class A EQ compost, meeting both regulatory and community sustainability goals.
PROJECT GALLERY
SG MOBILE® System
- Composting at Wastewater Treatment facility
- City of Florence, OR SG MOBILE® System
- FloGro® Compost Sample Pack and Educational Material
RESULTS DELIVERED: Scalable, Sustainable Biosolids Composting with FloGro®
Building on the success of its pilot program, the City of Florence expanded its biosolids composting operation by relocating the SG MOBILE® System to a dedicated asphalt pad in 2014 and installing in-ground aeration piping to enhance system performance.
By 2016, the City added a second SG MOBILE® System, doubling its processing capacity to 1,200 tons of Class A biosolids compost per year. The compost—now branded as FloGro® under the leadership of Public Works Director Mike Miller—has earned a strong local following for its quality. The City initially offered the compost free to Florence residents, and demand has consistently exceeded supply, with long lines forming before each distribution and the product disappearing within hours.
Today, the City of Florence continues to utilize SG’s modular CASP system with GORE® Cover to meet regulatory compliance, reduce landfill disposal, and produce a sought-after soil amendment. Plans are underway to expand the program into a larger-scale biosolids composting facility using the same proven technology.
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