SBIR Phase II:Energy-Efficient Supercritical Water Oxidation

The broader impact of this SBIR Phase II project is in the creation of a much-needed alternative to biosolids disposal. Biosolids are a by-product of wastewater treatment; their formation and disposal contribute to significant air, water, and soil pollution. In particular, biosolids contribute to greenhouse gas emissions and the release of over 350 organic contaminants, including high concentrations of per- and polyfluoroalkyl substances (PFAS). Biosolids disposal challenges are expected to grow due to population increases and stricter environmental regulations. Current biosolids disposal options have shortfalls and disposal costs are increasing. This project develops a breakthrough technology that cleanly and affordably destroys the organic contaminants present in biosolids. Air, water and soil pollution will be reduced, and, importantly, wastewater treatment plants will be able to meet new regulatory standards for sustainability. Volume of final by-product, and therefore transport cost and associated emissions, will be decreased by over 85%.The proposed project turns supercritical water oxidation (SCWO) into an energy-efficient technology by recovering compressive energy. SCWO rapidly and completely destroys organics. To date, the technology has been used in few applications, including chemical weapons dismantling. Recovery of compression energy saves 30-40% of total treatment cost, opening new markets, such as wastewater treatment.Recovery of compression energy during SCWO has been demonstrated previously.This project's goals are to further optimize, scale-up and iterate on compression energy recovery equipment for added capacity and reliability, and long-term field test these updated/new pieces of equipment by adding them to an existing supercritical water oxidation pilot system. The goal for the system is to achieve reliability on par with industrial high-pressure compressors, which can operate over 24,000 hours between major services.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.