PERACETIC ACID FOR MUNICIPAL WASTEWATER DISINFECTION

Peracetic Acid for Municipal Wastewater Applications

Introduction

Peracetic Acid (PAA) is an organic peroxide compound with the formula CH₃CO₃H. It is environmentally friendly as it hydrolyzes to acetic acid and hydrogen peroxide in water. It is a broad-spectrum biocide with a fast reaction time in minutes and leaves no harmful by-products.

It is a strong oxidant and disinfectant with oxidation potential higher than that of chlorine or chlorine dioxide. PAA is available in the form of equilibrium mixture which also contains hydrogen peroxide, acetic acid (vinegar) and water as shown by the following equation

CH3CO2H + H2O2 ←→ CH3CO3H + H2O
Acetic Acid + Hydrogen Peroxide ←→ Peracetic Acid + Water

Benefits in Wastewater Disinfection

• Replaces chlorine, sodium hypochlorite, and is a low-capital alternative to UV, chlorine dioxide and ozone.
• PAA decomposes into biodegradable components and does not create chlorinated compounds or harmful disinfection by-products.
• Has been shown to lower fecal coliforms counts quickly in effluent to satisfy discharge limits.
• Disinfection performance not impacted by variability in nitrite or ammonia concentrations.
• Can pass fish toxicity tests, showing no harm to aquatic life.
• With the proper dose, it does not alter the water quality that affects the discharge limits.
• In most applications, it does not require quenching of PAA residual.

Read More

Download Peracetic Acid-Municipal-Tech-Bulletin-17-LR (pdf)