Pharmaceutical factories will produce a large amount of sewage in the production process. We collectively refer to the sewage in this industry as pharmaceutical sewage; this kind of sewage needs to be treated by flocculation clarification and purification before it can be discharged. Due to the relatively complex composition of wastewater from pharmaceutical plants, when performing solid-liquid separation and dehydration treatment, the flocculant cationic polyacrylamide used in pharmaceutical wastewater treatment in general pharmaceutical plants.