Our technology for demonstration & commercialization:

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VaSA   for Ammonia Recovery from Wastewater and Digestate Treatment

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The Vacuum Stripping and Absorption (VaSA) technology was invented at SUNY College of Environmental Science and Forestry, Syracuse, NY and granted U.S. Patent No. 10,053,369 in 2018. It couples vacuum stripping and acid absorption to strip ammonia out of ammonia-rich wastewater (e.g., anaerobic digestate, landfill leachate, and liquid animal manure) under optimum vacuum and temperature combinations (typically 46 kPa and 65 degree Celsius) and recover the stripped ammonia by vacuum suction into acidic solutions for production of granular ammonium salts, sellable nitrogen fertilizers and reagent-grade chemicals. This unique process can reduce ammonia concentration from x,000 mg/L to less than 100 mg/L in a few hours of hydraulic retention.

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In addition, the vacuum stripping process enhances solids solubilization due to vacuum-assisted low-temperature thermal and mild-alkali treatment at the vacuum-temperature combination and subsequently increases methane production when stripped digestate is returned to the digesters. It improves dewaterability of digester effluent, and upgrades biosolids to Class A by pathogen reduction. It does not introduce stripping gases, neither need porous packing medium, thus eliminating the costly solid/liquid separation process. Compared with biological nitrogen removal, VaSA eliminates greenhouse gas emission.

Funded by NSF Partnerships for Innovation Program and NYS CoE in Healthy Water Solutions, onsite demonstration with 125-gallon VaSA prototype succeeded in January-June 2022 at The City of San Luis Obispo's Water Resource Recovery Facility and received the 2022 Award of Excellence in Innovation and Resilience from California Association of Sanitation Agencies. Pilot tests with landfill leachate were successfully carried out at the Regional Landfill at Ava, NY in May-July 2023.

The demonstration of 10-gallon VaSA prototype for pretreatment of dairy manure followed by 18-L anaerobic digesters was fulfilled with scraped and flushed dairy manure from Cal Poly Dairy in June-November 2022.