Separate coagulation from flocculation
Record the wastewater source, oils or suspended solids, pH and the existing coagulant program. Establish an untreated and coagulant-only comparison before evaluating polymer. Keep pH correction, chemical order and reaction conditions consistent.
CPAM may help form separable floc, but polymer cannot substitute for malfunctioning air delivery or an unresolved upstream treatment requirement. Match the trial to the actual condition at polymer injection.
Include the flotation step
Use a suitable flotation trial when available and document recycle conditions. Observe floc response after bubble contact, rise behavior, float stability and the quality of water below the floated layer. Compare at equivalent observation times.
In production, record hydraulic loading, recycle and skimmer conditions. Keep those settings stable during a chemical comparison. Overloaded hydraulics can mimic poor polymer selection.
Inspect the sludge as well as the water
Measure the required treated-water parameters and the concentration or handling of floated sludge. Floc that is easily fragmented or produces difficult sludge transfer can create downstream problems even when the initial water looks improved.
Use charge-profile selection to structure the sample set. Include the current product and preparation record in the DAF sample enquiry.