Coagulants for Oil & Refinery

In a refinery, coagulants are effluent-side chemicals: their job is breaking oily emulsions and cleaning up sour, oil-bearing water before biological treatment. Ferrous Chloride is the most refinery-specific product in this family — it serves refinery de-oiling and doubles as an H₂S scavenger, a valuable trait in sulphide-bearing sour-water and drain systems; it is also applied in oil-production water flooding. Ferrous Sulphate Solution is dosed on dissolved-air flotation units downstream of the API separator, where it destabilises the stubborn emulsified fraction the gravity stage cannot capture. Ferric chloride (CHIMIFLOC FR 4014) is applied for polishing and general clarification where a stronger trivalent coagulant is required. In the flowsheet, dosing sits between the API or CPI separator and the DAF unit, often paired with a cationic flocculant. Refinery buyers should evaluate candidates against real conditions: emulsion stability varies with desalter operation, tank-farm slops, and turnaround activity, so bench tests on worst-case DAF feed matter more than averages. Ask each supplier about dose response across your typical oil-in-water range, sulphide handling and its safety implications, materials for storage and dosing lines, and whether iron carryover to the biotreater is a concern in your configuration. Request the TDS and SDS up front.