Solutions Guide
Benzalkonium Chloride as a Cooling Tower & HVAC Biocide
Benzalkonium Chloride controls Legionella pneumophila, sulphate-reducing bacteria (SRB) and biofilm in industrial cooling towers, HVAC chillers and recirculating water systems. Vasudev Chemo Pharma supplies BKC 50% and 80% to water-treatment biocide formulators.
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Dosing programs
Routine biological control uses a 50–100 ppm active-quat slug dose; biofilm disruption and Legionella control use a 100–200 ppm shock dose (aligned with guidance such as HSE ACOP L8). BKC is most effective against gram-negative bacteria (Pseudomonas, Legionella, Enterobacter) and helps preserve heat-exchanger performance by reducing microbially-influenced corrosion (MIC).
Program compatibility
BKC is compatible with most phosphonate/polyacrylate dispersant programs and is typically alternated with an oxidising biocide for resistance management. Water-treatment companies formulate slug-dose products at ~20%–50% BKC (from 80% concentrate). Avoid anionic treatment chemicals that would deactivate the cationic quat.
Frequently asked questions
What BKC dose controls Legionella in cooling towers?+
A shock dose of 100–200 ppm active quat is typical for biofilm disruption and Legionella control; 50–100 ppm for routine biological control.
Is BKC compatible with cooling-water dispersants?+
Yes — it is compatible with most phosphonate/polyacrylate programs; alternate with an oxidising biocide for resistance management and avoid anionic chemicals.
Which grade do biocide formulators buy?+
BKC 80% concentrate, diluted to ~20%–50% in finished slug-dose products.