PFA technology: Production, safety and wastewater deployment analysis

Area of Science:

• Environmental Science
• Chemical Engineering
• Water Treatment Technology

Background:

• Performic acid (PFA) is a promising disinfectant for challenging water matrices like municipal wastewater and combined sewer overflows (CSOs).
• Its adoption is hindered by chemical instability, safety concerns, and the need for point-of-use generation.
• Evaluating PFA production and delivery systems is crucial for practical field deployment.

Purpose of the Study:

• To critically review and compare different PFA production and delivery architectures for wastewater disinfection.
• To assess the deployability of various PFA generation technologies based on performance, logistics, safety, and environmental factors.
• To provide a framework for selecting appropriate PFA technologies and identify research gaps for scalable deployment.

Main Methods:

• Integration of peer-reviewed literature and patent evidence to analyze five PFA technology families: on-site precursor blending, distillation/reactive separation, co-delivery formulations, microfluidic generation, and electrochemical synthesis.
• Application of a structured evidence base and readiness-aware scoring framework for comparative analysis.
• Interpretation of performance based on time-integrated residual exposure, considering oxidant decay and matrix demand.

Main Results:

• PFA demonstrates rapid bacterial inactivation and effective viral inactivation in some cases, often with reduced halogenated by-product formation compared to chlorination.
• On-site blending is the only widely validated municipal-scale PFA approach currently.
• Microreactors and reactive separation offer higher PFA strengths but face scale-up and complexity challenges; electrochemical methods are limited by low titers and dynamic response.

Conclusions:

• The effectiveness of PFA disinfection is highly sensitive to mixing, particulate shielding, and early oxidant consumption.
• Technology selection for PFA deployment must balance disinfection performance with production logistics, safety, control, and environmental considerations.
• Further research is needed to advance PFA technologies toward robust, scalable, and regulation-ready applications in wastewater and CSO disinfection.