Coagulants for Municipal Water Treatment

Coagulant selection in a municipal treatment plant is decided at the rapid-mix stage, where the chemical is dosed before clarification and filtration. In this duty, ferric chloride (CHIMIFLOC FR 4014, 40% ± 1% FeCl₃) is the reference iron coagulant for turbidity removal on surface-water intakes, and on the wastewater side of a utility it handles phosphorus removal and sludge conditioning. Plants that prefer aluminium chemistry use Liquid PAC - CHIMIFLOC PC 30 (10-12% Al₂O₃) or PAC Powder (28-30% Al₂O₃): polyaluminium chloride is pre-hydrolysed, so it typically consumes less alkalinity and works across a wider pH window — useful where source water has limited buffering capacity. Iron salts, in turn, typically produce a dense, fast-settling floc that suits high-turbidity intakes and existing sedimentation basins. Points a municipal buyer should weigh: seasonal turbidity swings, alkalinity of the raw water and the cost of pH correction, residual-metal targets at the tap, and the sludge volume each chemistry generates. Before contracting, ask for comparative jar tests on your own raw water, storage-material guidance (iron coagulants require polyethylene or lined tanks), the packaging path from 200 L drums to IBCs to bulk flexitank, and the TDS and SDS for every candidate product.