The largest tank Octaform has built to date.
The First District Association project in Litchfield, Minnesota required a 241 ft (73.5 m) diameter by 32 ft (9.8 m) high anaerobic digester on a compressed schedule, with winter conditions approaching. Delays risked additional cold-weather construction requirements or pushing portions of the work into the following spring.
The presence of hydrogen sulfide gas (H2S) also made corrosion protection a key design consideration, while alternative tank approaches required a separate interior coating system.
Octaform’s stay-in-place PVC concrete forming system provided a permanent interior surface while eliminating the need for a separate coating step. According to the design team, the approach reduced the anticipated overall project schedule by approximately two months and provided an estimated $750,000 initial construction cost advantage compared with the alternatives evaluated.
Project Partners
- Xylem, Lee & Company
- Robinson Construction
- Concrete Strategies
FROM FIRST-TIME INSTALLER TO LARGE-SCALE EXECUTION
Concrete Strategies was installing Octaform for the first time while delivering the largest digester tank by volume Octaform had supplied to date. Octaform Field Services supported the contractor through technical coordination, installation sequencing, pre-pour preparation, and concrete placement.
Octaform Advantages
Octaform’s solution provided decreased total costs compared to traditional methods involving concrete and polyurethane applied membrane coatings. This cost efficiency was instrumental in keeping the project within budget.
Octaform’s system significantly reduced construction time and labor requirements. The ease of installation contributed to a streamlined construction process, saving valuable time and resources.
Octaform’s system incorporated insulation directly into the structure. This ensured optimal thermal performance, with the thermal mass of concrete on the interior of the structure and insulation on the exterior, reducing operating costs.
The durability of Octaform’s tank interior was a crucial factor. The system resists corrosion and requires no mid-life servicing or re-coating, further reducing long-term maintenance costs.
Octaform’s PVC stay-in-place forming system offered superior corrosion resistance compared to traditional concrete and membrane systems. This durability ensures a longer service life for the infrastructure.
Outcomes
Corrosion protection. Accelerated construction. Cost efficiency.
For First District, close coordination between the design team, EPC, concrete contractor and Octaform Field Services supported the successful delivery of large-scale anaerobic digestion infrastructure.
Xylem, Lee & Company
Robinson Construction
Concrete Strategies
Two factors were particularly important in specifying Octaform: corrosion protection and schedule. Octaform allowed us to reduce the overall project schedule by approximately two months and provided an initial construction cost advantage of approximately $750,000 compared with the alternatives we were considering.
Conclusion
“Despite it being a very large tank, and the first we delivered with Octaform, the experience of Octaform’s Field Services team prepared us for the challenge ahead. Their attention to detail at each phase of execution was impressive. By the time we completed the second tank, we were able to wrap it up in just 17 working days from slab to completion, including scaffolding erection”.
ERICK HERMANN, Vice President, Strategic Accounts, Concrete Strategies.
