AD-402 Cooling Biocide for Textile Dyeing in Faisalabad
Isothiazolinone biocide for the cooling and chiller loops feeding Faisalabad dye-houses and finishing lines. Long-residual control, AD-401 rotation pair.
Faisalabad dye-houses run cooling loops on every stenter, beam-dyeing chiller, jet-dyeing machine, and continuous-dyeing range. Most are mid-sized open recirculating towers (500–4,000 m³/h) plus closed chiller circuits on the chillers themselves. Cooling chemistry is rarely top-of-mind until a tower fouls and the process water swings off-spec.
Textile dyeing process water often carries stray dye, surfactant, and organic load into the cooling makeup line via heat-exchanger leaks or shared raw-water pretreatment. That organic load feeds biofilm faster than a clean industrial cooling loop, and isothiazolinone biocides handle the resulting microbial profile better than glutaraldehyde or DBNPA.
Brand audits (HIGG FEM 4.0, ZDHC) increasingly look at cooling-water microbial counts as part of the overall facility health score. AD-402 with its CMIT/MIT actives lands inside the GreenScreen and ZDHC conformant chemistry envelope when used at the recommended concentration ranges.
Faisalabad-Karachi freight on AD-402 is 2–3 days on stock-spec. We pair AD-402 with AD-401 in rotation programmes for textile cooling loops because resistance development on a single non-oxidising chemistry is documented across long-running cooling water.
AD-402 is an isothiazolinone-based non-oxidising biocide: CMIT/MIT actives at 14% combined, pH 2.0–5.0, clear-to-amber liquid. Long-residual mode of action; rapid kill followed by sustained inhibition of regrowth across 2–5 days depending on system. Designed to alternate with AD-401 and oxidising biocides in resistance-management programmes.
- Stage: dosed into the cooling-tower basin, recirculating header, or closed-chiller make-up line.
- Function: rapid kill of the planktonic bacterial population, plus 2–5 day residual inhibition of regrowth in the bulk water and on heat-transfer surfaces.
- Shock dose: 30–100 ppm, contact time 4–6 hours.
- Continuous dose: 10–30 ppm on systems with ongoing biofouling pressure (high organic load, dye-stuff carryover, leaking heat exchangers).
- Rotation: alternate with AD-401 every 3–7 days, plus an oxidising biocide (chlorine or stabilised bromine) on a different cycle. We write the calendar.
Where AD-402 chemistry has run on textile dyeing sites near Faisalabad.
Selected, anonymised. Site-specific case studies and references shared on supplier-qualification request.
Stenter cooling loop · Sammundri Road · 2024
AD-402 + AD-401 rotation on a 6,000 m³/h tower serving a finishing line. Bacterial counts held at <10⁴ per mL; cycles-of-concentration sustained at 5.0+.
Beam-dyeing chiller circuit · 2023
Closed chiller loop biofouling event resolved with AD-402 shock dose; process water spec restored within 48 hours.
Continuous-dyeing range cooling · 2022
12-month programme of AD-402 alternation with chlorine. Brand audit (HIGG FEM 4.0) cleared first pass on chemistry documentation.
Tell us your site, the loop, the symptom, the volume.
Same-business-day reply from Karachi with a programme outline and the relevant CoAs / SDS attached. Or WhatsApp the engineering line directly; same engineer who writes the dosing programme answers the message.