Ranipet, Vellore and Ambur tannery CETPs: a guide
How tannery CETPs in the Palar valley handle protein, fat, lime and chrome-bearing effluent and its heavy sludge, and where polymer helps most.
The Palar valley leather belt
Tanneries from Ranipet through Vellore to Ambur and Vaniyambadi form one of India's largest leather clusters. Most send effluent to common effluent treatment plants, which work under strict limits on chromium, dissolved solids and suspended solids.
What tannery effluent carries
Soaking, liming and unhairing produce salty, alkaline effluent with hair, protein, fat and sulphide. Chrome tanning adds trivalent chromium. Volumes and strength vary with the stages each tannery is running.
Chrome segregation
Chrome-bearing liquors are best kept separate and treated for chrome recovery, so that less chromium reaches the CETP and the sludge.
Primary treatment at the CETP
After equalisation and coagulation, a cationic grade such as Cationic HQ gathers the protein, fat and fine solids into large flocs that settle in the primary clarifier, protecting the biological stage. SunMac SC04 can support the coagulant on protein-rich loads.
Heavy sludge
Tannery CETPs generate a lot of dense sludge. Good conditioning with a cationic polymer helps filter presses and centrifuges release water, which cuts the volume and cost of disposal.
Regulation and supply
CETPs are regulated by the Tamil Nadu Pollution Control Board. Ranipet is about 110 km from Chennai, so same-day or next-day supply is often possible.
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.