Polyelectrolyte for tannery effluent
Tannery effluent carries protein, fat, chrome and lime, and most units discharge to a common effluent treatment plant that sets strict limits. A good flocculant keeps the primary clarifier working.
Sunfloc Cationic HQ for regular plant use, or Cationic MQ for smaller plants and trials. Confirm on your own sample with a free jar test.
Which charge
Cationic polyacrylamide is the usual choice for tannery wastewater. Start with Cationic HQ or Cationic MQ.
Primary treatment
The polymer goes in after lime or metal-salt coagulation, at a point of gentle mixing before the primary clarifier.
Sludge
Tannery sludge is heavy and voluminous; a cationic grade helps the press release water and form a firm cake. See sludge dewatering.
CETP members
If your unit feeds a CETP, test on the effluent you actually send. We run the jar test on your sample free of charge.
Related
Polyelectrolyte dosing guide
Starting doses, solution strength and how to work out kilograms per day.
Read →Where this work clusters
Why tannery water behaves differently
Tannery effluent carries protein, fat, hair and fine solids, plus salt and chromium in some streams. The organic solids tend to carry negative charge, so a cationic polymer is the usual choice for the primary clarifier, with an anionic grade for chrome-bearing precipitates after pH correction.
Screen and equalise first. Dosing straight into an unscreened stream wastes polymer on material a screen would have removed. The jar test should be done on the equalised flow at the pH it will actually run at.
Discharge limits are set by your state board under the Environment (Protection) Rules, whose general standard lists a pH of 5.5–9.0 for discharge to inland waters. Many tannery belts also work to zero liquid discharge, so a clear overflow matters for the stages that follow.
Sources: Schedule VI general standards for effluent discharge (state pollution control board copy); ASTM D2035-19, Coagulation-Flocculation Jar Test of Water.
Not sure which grade suits your water?
Send us a one-litre sample or describe your process. We test it in our lab free of charge and recommend a grade and starting dose, and quote within 1 business hour.