One of the most common questions we hear from water treatment plants in Vietnam and Indonesia: do I need PAC, PAM, or both? The short answer is that they are not competitors — they do two different jobs, and most plants get the best result using them together. This guide explains what each one does, when to use which, and what it costs.
PAC (polyaluminum chloride) is an inorganic coagulant. Suspended particles in water — clay, algae, organic matter — carry negative surface charges and repel each other, which is why they stay suspended. PAC releases aluminum species that neutralize these charges, so fine particles destabilize and clump into small, visible flocs called "microflocs." PAC works fast (within minutes), is inexpensive, and performs well across a wide pH and temperature range, which makes it the default first step in most clarification trains.
PAM (polyacrylamide) is an organic flocculant — a long-chain synthetic polymer. Its molecules are millions of units long; they adsorb onto several particles at once and physically bridge them into large, dense, fast-settling flocs. PAM does not create flocs from clear water — it needs the microflocs already formed by a coagulant (or naturally present solids, as in mining tailings) to grab onto. Used alone, it is the workhorse for sludge dewatering, where cationic PAM conditions the sludge before a belt press or centrifuge.
| Type | Charge | Typical use | Reference FOB price |
|---|---|---|---|
| Anionic PAM | Negative | Mining, sand/coal washing, industrial wastewater, drinking water clarification (as coagulant aid after PAC) | US $1,000–1,450 /ton |
| Cationic PAM | Positive | Sludge dewatering, MBR systems, municipal wastewater (biological sludge is negatively charged) | US $1,300–2,500 /ton |
| Nonionic PAM | Neutral | Textile sizing, paper retention, special industrial processes, acidic/alkaline conditions where charged polymers fail | US $1,000–1,600 /ton |
Reference FOB China port; final quote by grade, quantity and market.
If your goal is turbidity removal in a sedimentation tank or DAF unit and the flocs settle acceptably, PAC alone is usually enough. Powder PAC (Al2O3 28-31%, US $230–350 /ton FOB) is the general-purpose choice; liquid PAC (10-12% Al2O3, US $150–190 /ton) suits plants with on-site storage that want to skip dissolving steps.
Sludge dewatering, thickened mining tailings and coal-washing circuits already carry high solids — a cationic (for organic sludge) or anionic (for mineral slurry) PAM alone is the right tool. Adding PAC here usually just increases chemical cost and sludge volume.
High-turbidity surface water, dyeing effluent, food-processing wastewater: dose PAC first to destabilize, then a low dose of anionic PAM 30-60 seconds later to grow the microflocs into settleable ones. Plants typically report PAC savings of 20-40% when a small PAM dose is added, because the coagulant no longer has to do the flocculation job alone. The exact doses come from a jar test — never from a formula alone.
| Your situation | Start with | Why |
|---|---|---|
| Drinking water, turbidity 50-500 NTU | PAC powder 28-31% | Fast charge neutralization, GB 15892 drinking-water grade available |
| Industrial wastewater with high COD/color | PAC + anionic PAM | PAC removes colloid charge; PAM builds settleable flocs |
| Mining / sand washing tailings | Anionic PAM (high MW) | High solids need bridging, not coagulation |
| Municipal sludge before belt press | Cationic PAM | Positive charge binds negatively charged organic sludge |
| Phosphorus removal to discharge limit | PFS or PAC (+ PAM polish) | Iron/aluminum salts precipitate phosphate chemically |
Send us your water source, turbidity, pH and treatment target. We will recommend a grade, ship free samples (500g–1kg, you only cover courier), and support your jar test remotely. Compare settling speed, supernatant clarity and chemical cost per treated ton — then order one container with mixed products if you need both PAC and PAM. Mixed-container loading is standard for us and reduces your per-ton freight.
Related products: PAC Powder · Anionic PAM · Cationic PAM · Nonionic PAM · PAC dosage calculation guide