Benefits of HALT 

Yes, Aquagga is the exclusive licensee of the foundational HALT patent from the Colorado School of Mines. We also hold an exclusive license to hydrothermal processing IP from the University of Washington.

HALT is similar to supercritical water oxidation (SCWO) in its ability to destroy PFAS compounds, but it operates under milder conditions. Instead of using an oxidant, HALT utilizes an alkaline amendment to drive PFAS destruction. This allows the system to run at subcritical temperatures and pressures, with less process complexity and more operational flexibility.

We use an inexpensive and widely available caustic amendment to drive effective PFAS destruction, typically sodium hydroxide (NaOH).

HALT is designed for challenging, high-strength waste streams. Higher PFAS concentrations, resulting from treatment steps before HALT, ensure that HALT treatment is efficient and economical. HALT can treat PFAS-containing wastewater, as well as feedstock containing total dissolved solids (TDS) and total organic carbon (TOC). Suspended solids are generally removed via pre-filtration before treatment.

The resulting effluent is a salt water solution neutralized to a neutral pH. Depending on project needs, the effluent can be polished or recirculated within the treatment train to meet specific water quality requirements.

HALT has been rigorously tested by both the private sector and the U.S. Department of Defense. We use standard LC-MS/MS analysis to measure PFAS levels coupled with fluoride ion-selective electrode (ISE) or ion chromatography (IC) of free fluoride. We may also apply non-targeted LC-QToF-MS and ¹⁹F NMR to validate complete mineralization and ensure no fluorinated byproducts remain. Please refer to our publication for more information.

Unlike other thermal treatment technologies, HALT does not involve combustion or chemical oxidation, and does not produce gaseous CO2 as a byproduct. Testing via EPA methods for volatile or aerosolized PFAS compounds (OTM-45, OTM-50, OTM-55) has confirmed that HALT does not produce gaseous or volatile organofluorine (VOF) byproducts when operated at our standard temperatures and pressures. When treating materials high in organic content, such as AFFF, low levels of volatile organic compounds (VOCs) are generated during the HALT process. These are well characterized, the levels are far below permissible exposure levels, and they are further mitigated by general health and safety procedures on-site.

Yes. All HALT systems are available to order. Lead times, site requirements, and flexible payment arrangements vary. Please contact us to discuss your project needs.