Aqueous Film-Forming Foam (AFFF), a critical tool in combating flammable liquid fires, has long been utilized by sectors such as municipal firefighting, aviation, military and petrochemical industries.
Its effectiveness stems from its unique composition, which includes per- and polyfluoroalkyl substances (PFAS).
However, PFAS are highly persistent in the environment and pose significant risks to human health and ecosystems, necessitating urgent measures for their safe destruction.
The U.S. Department of Defense (DoD) and the European Union (EU) have introduced stringent regulations, including the transition to fluorine-free firefighting foams by 2024.
Meanwhile, several states have implemented buyback programs to safely dispose of AFFF stocks.
Addressing this challenge, 374Water Inc.
has developed the AirSCWO system, a supercritical water oxidation (SCWO) technology, which has proven effective in breaking down even the most recalcitrant PFAS compounds without generating harmful byproducts.
AirSCWO uses high temperatures and pressures to oxidize PFAS into water and carbon dioxide, achieving 99.9999% destruction in seconds.
Lab and full-scale trials confirmed this efficiency across three system configurations: lab-scale, AS-1 for smaller applications and AS-6 for industrial use.
Operating at 600°C and 3500 psi, AirSCWO breaks PFAS molecular bonds, ensuring safe and scalable waste management.
The AS-6 system processes up to six wet tons of waste daily, meeting stringent environmental standards.
This technology provides a crucial solution for AFFF disposal, aligning with regulatory demands for reducing PFAS contamination in water and soil.
374Water’s AirSCWO technology offers a practical and safe solution by achieving over 99.99% destruction of PFAS within seconds through SCWO.
This technology could redefine how the sector approaches the disposal of hazardous materials, aligning with strict environmental regulations while protecting public health.
FSJA spoke to Sudhakar Viswanathan, Vice President at 374Water to find out how AirSCWO can serve the unique needs of the fire and safety sector, ensuring safer and more sustainable operations.
AFFF is widely used in firefighting, particularly for flammable liquids like gasoline, oil and jet fuel.
Its popularity and importance in fire safety stem from features like rapid fire suppression as the foam forms a film layer over the fire and chokes the oxygen supply, suppressing the fire.
The foam also cools the fuel, prevents vapor release and is easy to use, making it the preferred firefighting agent for Class B fires.
PFAS in AFFF are highly persistent in the environment, bioaccumulative and linked to health risks including cancer, posing long-term dangers to firefighters, who are consistently using them in both training and in the field and anyone encountering this compound in environmentally impacted resources such as drinking water.
374Water’s AirSCWO technology addresses the challenge of safely disposing of AFFF by using a process called supercritical water oxidation (SCWO) to break down organic compounds, including PFAS, at the molecular level.
This advanced process operates at high temperatures and pressures, where water becomes supercritical, enabling the complete oxidation of organic contaminants using air, into harmless byproducts like water, carbon dioxide and inert salts.
Unlike traditional methods, AirSCWO eliminates the creation of secondary waste, ensuring a clean and environmentally friendly solution for AFFF disposal.
When PFAS go through the AirSCWO process, they are exposed to extreme heat, pressure and oxygen in a supercritical water environment, breaking their strong carbon-fluorine bonds.
This reaction, known as mineralization, transforms organic compounds into inorganic compounds such as water, carbon dioxide and inert salts, ensuring the complete and permanent destruction of PFAS without creating secondary pollutants.
It is crucial for fire departments to have a reliable way to dispose of stockpiled AFFF because it often contains PFAS, which poses significant risks to human health and the environment if incidentally released.
Proper disposal prevents contamination of soil and water, reduces liability and ensures compliance with evolving environmental regulations while protecting firefighters and communities from long-term exposure to hazardous substances.
AirSCWO technology is ideally deployed at centralized facilities, as part of a Destruction as a Service (DaaS), rather than directly at fire stations.
Waste such as AFFF can be transported from a specific region or state to these facilities for safe processing.
For larger-scale operations (e.g. airports, military bases), modular AirSCWO systems can potentially be installed on-site, providing a practical and efficient solution for safely destroying hazardous materials, including PFAS, at the source.
AirSCWO stands out from other hazardous material disposal methods because it uses supercritical water oxidation to completely destroy organic contaminants, including PFAS, through a process called mineralization.
Unlike incineration or landfilling, AirSCWO operates in a closed system, eliminates the risk of harmful emissions or secondary waste and converts hazardous materials into benign byproducts like water, carbon dioxide and inorganic salts.
This environmentally friendly approach ensures complete destruction with minimal environmental impact, making it a cleaner, safer and more sustainable solution.
AirSCWO technology ensures safety for those working with it, including firefighters and disposal teams, by operating in a closed system under controlled conditions.
Firefighters using the DaaS, will not come in contact with the 374Water AirSCWO process, which breaks down hazardous substances like PFAS into harmless byproducts, such as water, carbon dioxide and inorganic salts, without creating harmful emissions or secondary waste to handle/further manage.
Additionally, the system is designed with advanced safety features, such as pressure relief valves and automated monitoring, to maintain safe operating conditions and minimize any risk to personnel.
This ensures that the technology provides an effective yet safe solution for handling hazardous materials.
Through our Destruction as a Service (DaaS) delivery model, 374Water can provide comprehensive support to fire departments and States with AFFF take-back programs, offering a safe and hassle-free way to dispose of AFFF and other PFAS wastes.
With DaaS, departments can send materials to our facility for complete destruction using AirSCWO, eliminating the need to manage high-pressure systems directly.
We also assist with waste logistics and regulatory compliance, ensuring safety and convenience.
For larger-scale needs, we offer leasing or purchase options with training and technical support tailored to their requirements.
With the ability to effectively destroy PFAS found in AFFF, AirSCWO offers the industry a long term viable solution to addressing the disposal and management of these materials.
The fire and safety sector also often deals with hazardous materials, including chemical residues and contaminated gear, which can now be safely disposed of using SCWO.
By effectively neutralizing harmful substances like PFAS, SCWO reduces long-term exposure risks for firefighters who come into contact with contaminated water, foam, or equipment, improving occupational health outcomes.
