374Water Inc (NASDAQ:SCWO, FRA:8LL) said it has finished three phases of its mobile AirSCWO deployment in St. Cloud, Minnesota, treating three biosolids feedstocks, and has begun a fourth campaign phase.
The cleantech company, which uses supercritical water oxidation technology to destroy PFAS and other organic waste streams, is carrying out the work under a $600,000 Waste Destruction Services contract with the City of St Cloud. The project, run with Barr Engineering at St. Cloud's water recovery facility, is part of Minnesota's AirSCWO evaluation, backed by state resource and trust funds.
Between June 1 and July 31, the field team treated Class B biosolids, Class A biosolids and pre-digestion sludge under varying operating conditions. The company said Phase 3 concluded with no operational issues and that it is now analyzing performance data, with results consistent with previous campaigns.
"What makes this deployment unique is the emphasis on robust mass and energy balances around our mobile unit, and optimization of the sampling intervals to account for dynamics of the system,” chief technology officer Raj Melkote told shareholders.
Phase 4, which began August 10, focuses on treating Class B biosolids blended with spent granular activated carbon from a drinking water purification plant in Cottage Grove, Minnesota.
"Our team has done a fantastic job at integrating our technology into St. Cloud's facility, completing three phases across three very different biosolids feedstocks with no operational issues," said Brad Meyers, Chief Operating Officer of 374Water. "While we finalize our analysis of the data, the performance we've observed to date has been encouraging and in line with what we expect from AirSCWO.”
374Water said a successful pilot could support Minnesota's broader assessment of AirSCWO for permanent PFAS destruction, with the mobile system estimated to generate between $500,000 and $1.5 million in annual revenue per unit.
Shares of 374Water were up 3% on Tuesday morning.