Stircor develops process to remove PFAS from biosolids

Stircor, a Nashville, Tennessee-based provider of biosolid processing, drying and gasification services, has developed a process for removing per- and polyfluoroalkyl substances (PFAS) from biosolid waste for U.S. municipalities.

The biochar—a lightweight black residue consisting of carbon and ashes that remains after the pyrolysis of biomass, and form of charcoal—resulting from Stircor’s proprietary drying and gasification process, was tested by U.S. Environmental Protection Agency (EPA) accredited third-party laboratory using the EPA’s Method 1633. Method 1633 includes 40 target analytes, all of which were below the limit of detection.  

“We’re proud that our process for drying and gasifying biosolid waste has been proven to remove harmful PFAS chemicals,” Stircor CEO Forrest Porterfield says. “We’ve worked with our partners over the last several years to refine and develop a process that creates a biosolid-derived biochar suitable for beneficial reuse.”

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Stircor's biochar byproduct is PFAS-free, making it suitable for various applications, including agriculture, construction, energy and waste treatment. Additionally, the gasification process qualifies for carbon credits due to its contributions to carbon sequestration and greenhouse gas reduction.

In addition to developing a process for removing PFAS from biosolids, the Stircor team and its carbon crediting and sustainability expert, Lincoln Day, have refined the process to obtain carbon credits for biochar and sustainable practices created by Stircor’s method.

“These improvements in the process for managing biosolid waste mean that municipalities can take what was once a problem to be solved or disposed of and turn it into a useful and beneficial service for their communities,” Porterfield says. 

Stircor works with municipalities and agricultural organizations to process, dry, gasify and dispose of biosolid waste through sustainable processes.