From Waste to Worth: Turning Digestate and Regulation into Opportunity

“What was once waste is becoming a resource.”

By @Zoe Astill, BiogasWorld

In the renewable natural gas (RNG) and biogas industry, even the byproducts are getting a second look. What was once viewed as a disposal challenge is now being redefined as a valuable asset.

In BiogasWorld’s recent webinar, “The U.S. Biogas & RNG Market: Navigating 2025 and Beyond,” industry experts from ABB, Ivys Adsorption, Mead & Hunt, and Fournier emphasized that one of the biggest shifts ahead isn’t just in gas production, but in how the industry manages and valorizes its digestate amid evolving PFAS regulations and tightening biosolids standards.As the U.S. biogas sector matures, attention is shifting from gas output to total resource efficiency, and digestate, the nutrient-rich residue from anaerobic digestion, is at the center of this transformation. With new regulations emerging around PFAS (“forever chemicals”) and biosolids management, developers, engineering firms, and equipment manufacturers are exploring how to turn digestate into a profitable and sustainable co-product rather than a cost center.

Digestate Market Trends and Policy Outlook

Digestate contains valuable nutrients, including nitrogen, phosphorus, and potassium, making it an excellent fertilizer and soil amendment. However, policy uncertainty around PFAS contamination has introduced complexity into how it’s managed, processed, and marketed.

During BiogasWorld’s webinar, Fournier Industries emphasized that upcoming PFAS regulations could significantly reshape the digestate market. As states tighten limits on biosolids land application, testing requirements and disposal costs are expected to rise, but this pressure is already catalyzing innovation.

Developers are exploring nutrient capture systems, fertigation-ready liquid digestate, evaporator-compatible dewatering, and advanced separation technologies that reduce PFAS concentrations, reduce disposal liability, and unlock new agricultural value. The message emerging across the industry is clear: compliance is not the end goal, circularity is.

Innovation in Digestate Processing

Fournier Industries, a long-standing manufacturer of solids-handling technologies for wastewater and renewable energy sectors, has been at the forefront of digestate innovation. Their Fournier Rotary Press, a low-energy solid-liquid separation system, has become a benchmark for energy-efficient biosolids handling in both wastewater and RNG facilities across North America and Europe.

By minimizing energy use and maintenance costs, the Rotary Press enhances plant performance while contributing to lower carbon intensity (CI) scores. Its efficient dewatering produces a drier, more manageable cake, ideal for composting, nutrient extraction, pyrolysis feedstock, or even biochar production.

Fournier is also exploring next-generation digestate treatment systems capable of removing PFAS and concentrating nutrients, creating cleaner, higher-value outputs tailored to emerging regulatory and market requirements. This push for better separation and cleaner digestate aligns with broader international trends. As McKay highlighted, in Sweden, the liquid digestate is reused in farms for fertigation (fertilizing and irrigation at the same time).

The future of digestate processing will be defined by technologies that simultaneously enable nutrient recovery, regulatory compliance, and end-market reliability.

Economics and Circular Value Creation

Turning digestate into a resource is not just a sustainability play; it’s a financial strategy.

Valorized digestate products, including organic fertilizers, concentrated nutrient solutions, and soil enhancers, can open new revenue streams for biogas operators while reducing waste management costs and improving project bankability.

Every ton of digestate successfully reused or sold improves the overall return on investment (ROI) and strengthens the project’s environmental credit profile. Meanwhile, nutrient circularity strengthens CI performance, an increasingly important metric under emerging clean fuel standards and voluntary carbon markets. However, long, long-term market certainty remains a barrier:

Still, rapid innovation in nutrient capture, organic fertilizer markets, and digestate processing is enabling developers to move beyond “gas-only” thinking, transforming byproducts into core revenue contributors.

Regulation as a Catalyst for Innovation

While PFAS regulations may appear restrictive, they are already acting as a catalyst for innovation across the biogas value chain. Developers, engineering firms, and equipment manufacturers are collaborating to define digestate quality standards that protect public health while opening new pathways for nutrient reuse and biosolids valorization. This is driving advancements in testing, advanced filtration, nutrient concentration, and PFAS mitigation technologies. Across the webinar panel, a consistent theme emerged:

At BiogasWorld, we view this moment as an opportunity for the industry to lead, to set the standards for sustainable digestate management before regulations do. By sharing data, piloting technologies, and aligning with circular economy goals, the biogas community can turn today’s challenges into tomorrow’s competitive advantage.

Join the conversation on the Biogas Community platform and help shape the future of digestate valorization in North America.

Want more insights? Check out the webinar here: US Biogas & RNG Market: Navigating 2025 & Beyond