Challenge

Sonoco, a global leader in packaging solutions, faced mounting pressure to reduce Scope 1 emissions from its manufacturing operations. One of its key facilities in the Southeast U.S. was producing high-strength organic wastewater as a byproduct of paperboard production, which resulted in significant methane emissions and costly sludge handling.

Solution

GreenGas partnered with Sonoco to assess the biogas potential of its wastewater stream. Following a detailed site analysis, GreenGas installed a custom anaerobic digestion and gas upgrading system, fully funded by GreenGas, requiring no capital investment from Sonoco.

The solution included:

• Anaerobic lagoon optimization for methane capture
• Advanced biogas cleaning and compression equipment
• Pipeline injection infrastructure for high-BTU RNG
• Long-term offtake agreements for renewable thermal certificates (RTCs)

Results

• 93% methane recovery from the wastewater stream
• 85% reduction in sludge volume and hauling costs
• Generation of certified RNG contributing to over 7,000 MTCO2e in annual emissions reductions
• $500,000+ in projected annual revenue from feedstock sharing
• Significant odor reduction and improved compliance with local environmental standards

Bonus Impact

As part of a continuous improvement initiative, GreenGas also implemented a CO2 recovery unit at the site, converting waste gas into beverage-grade liquid CO2—reused by Sonoco in its cooling and packaging processes.

“GreenGas helped us transform a waste liability into a source of revenue and sustainability leadership. It’s been a game-changer.”

— John Smith, Facilities Director, Sonoco.