Carollo Engineers Inc., South Platte Renew (SPR) and J.R. Filanc Construction Company recently received the Water Environment Federation’s (WEF) 2020 Project Excellence Award for the $7.8-million SPR Gas Recovery Facility and Pipeline Injection Project. This annual distinction recognizes innovative projects and programs in the water sector. The 2020 project winners were honored during WEF's virtual Technical Exhibition and Conference, WEFTEC Connect, on Oct. 7.
The project designed and constructed the first system in Colorado to convert raw biogas from a water resource recovery facility (WRRF) to renewable natural gas (RNG) and inject that product into a natural gas pipeline for downstream use as transportation fuel. The new gas recovery facility is anticipated not only to deliver vast environmental benefits to local communities but also to generate a valuable revenue stream for SPR.
"The Pipeline Injection Project is a unique approach in innovation that will benefit our environment, our customers, and our facility,” said SPR Director Pieter Van Ry. “We are beyond excited to share this pioneering accomplishment with our communities."
SPR operates the third largest WRRF in Colorado, treating nearly 20 million gallons of wastewater a day from 300,000 residents in Littleton, Englewood, and 19 other connecting communities. The facility has a permitted capacity of 50 million gallons per day and generates approximately 500,000 cubic feet per day of biogas through anaerobic digestion.
In 2016, SPR hired Carollo to evaluate sustainable and cost-effective options to beneficially reuse the WRRF’s biogas, which was one of the focus areas of SPR’s 2014 Energy Improvement Program. Carollo recommended that SPR install a biogas-upgrading system that treats biogas and injects RNG directly into a nearby natural gas pipeline owned and operated by the Public Service Company of Colorado, a subsidiary of Xcel Energy. Carollo designed the upgrading system, which removes carbon dioxide, hydrogen sulfide, siloxanes, moisture, and volatile organic compounds from raw biogas.
“While the technology used to convert biogas to RNG is established, pipeline injection projects remain few and far between in the U.S.,” said Carollo project manager Becky Luna. “Project success required stakeholder buy-in and extensive coordination with Xcel Energy. We commend SPR for their vision and steadfast commitment to reducing greenhouse gas emissions.”
Beyond its environmental merits, pipeline injection also provides a relatively rapid return on investment, thanks to incentive credits from the U.S. Environmental Protection Agency's Renewable Fuel Standard Program. Just in 2020, the gas recovery facility is projected to receive $1.5 million in revenue and has an overall project payback of five to seven years.
This project was delivered with a construction manager/general contractor (CMGC) delivery model for the construction phase with Filanc serving as the CMGC contractor. SPR also hired carbon broker Bluesource to sell both the RNG (brown gas) and green credits (renewable identification numbers) associated with the injected gas.
