Once the local landfill stopped accepting biosolids, the city of Granby, CO was faced with a long and difficult haul from high in the Rockies to the low land biosolids disposal companies. The rapid rate of local development and high cost of composted products also made for a good market opportunity. The Sanitation District decided to explore composting. Their facility would require:
- Operation through winter when temperatures could reach -30F;
- Operation with exiting staff;
- Fit within a very limited footprint; and
- Provide excellent odor control.
Once selected as the compost process equipment vendor, ECS worked with the client’s consulting engineer to develop the detailed facility design for construction. ECS configured its In-Vessel Tunnel technology to provide a robust all-weather composting system. The system was sized for 100 annual dry tons of biosolids and bulked with ground wood amendment. The four in-vessels Tunnels are site-constructed of formed concrete. The vessels are corrosion proof, sealed, and highly insulated. All condensate and leachate drains down to internal, thermally protected sumps. A mobile mixer is pre-loaded with amendment and used to receive the dewatered biosolids directly from the press. It is pulled a short distance to the vessels where the it is turned on and discharged directly into the vessels using a small rotary stacking conveyor. The vessels are designed to process up to 70 yd3 of mix each. The CompTroller™ automated aeration control and compost monitoring system operates with minimal operator input and produces time-temperature records for regulatory compliance.
Granby’s compost is advertised in flyers that go out to their customers, and by word-of-mouth. The compost is offered free to their WWTP customers; and is sold to a loyal clientele base of landscaping companies, golf courses, and resorts that are clamoring for their compost.
ECS Technologies Employed
CompTroller™ Automated Control & Monitoring System
Tunnel In-Vessel System
Reversing Aeration System
Horizontal Auger Compost Mixer
Stationary Trommel Screen
"The Granby Sanitation District takes its role in the protection of the public health and the environment very seriously. Our compost system has been a huge asset in that endeavor by allowing us to (almost completely) eliminate our usage of landfills in the disposal of wastewater treatment by-products. The ECS equipment (in vessel tunnel system, four auger mixer and loading conveyor) has been very reliable, requiring only routine maintenance over the past ten years or so of continuous operation."
- Hopper Becker
Read about Granby's Facility on our Comp Blog.
Visit the Granby Biosolids Compost Facility online.