Coagulation is the first step in clarifying most raw waters and effluents. Three inorganic coagulants are used widely, each with its own strengths.
Poly Aluminium Chloride (PAC)
PAC is a pre-polymerised aluminium coagulant. It typically works across a wider pH range than alum, forms flocs quickly and often needs a lower dose.
Aluminium Sulphate (Alum)
Alum is a long-established, economical coagulant. It performs best within a narrower pH window and usually consumes alkalinity, so pH correction may be needed.
Ferric Chloride
Ferric chloride forms dense, fast-settling flocs and is effective for phosphate removal and many industrial effluents. It is corrosive, so handling and dosing equipment must be suitable.
Making the choice
The right coagulant depends on raw-water quality, pH and alkalinity, target turbidity, sludge handling and cost per cubic metre treated. Jar testing on your actual water is the most reliable way to decide — and our team can help you source the products to trial.
