WASHINGTON — Oct. 9, 2015 — DC Water has unveiled its $470 million waste-to-energy project, which will generate clean, renewable energy and produce a nutrient-rich soil byproduct from the wastewater treatment process, according to a press release.
New technology installed at the Blue Plains Advanced Wastewater Treatment Plant in southwest D.C. will produce a net 10 megawatts (MW) of electricity, powering about one-third of the plant’s energy needs, stated the release.
The facility is the first in North America to adopt the CAMBI thermal hydrolysis process and is now the largest thermal hydrolysis installation in the world, noted the release.
According to DC Water, the process uses high heat and pressure to “pressure cook” the solids left over at the end of the wastewater treatment process. This weakens the solids’ cell walls and the structure between cells to make the energy easily accessible to microorganisms in the next stage of the process — anaerobic digestion.
The methane produced by these microorganisms is captured and fed to three large turbines to produce electricity, the release reported. Steam is also captured and directed back into the process.
At the end of the process, the plant is left with a cleaner Class A biosolids product that can be used as a compost-like material.
“This project embodies a shift from treating used water as waste to leveraging it as a resource,” commented DC Water CEO and general manager George S. Hawkins in the release. “We are proud to be the first to bring this innovation to North America for the benefit of our ratepayers, the industry and the environment.”
You can find the entire release here.