How to select the right Cationic Polyacrylamide?
2026-04-14 10:40:28
Selecting the correct Cationic Polyacrylamide(CPAM)depends on sludge type,organic content,pH,wastewater composition,and dewatering equipment.Below is a clear,practical guide for industrial and export applications.
1.Select by Ionic Degree(Most Important)
Low ionic:10%–20%
Inorganic sludge:sand washing,mining,river silt,boiler ash.
Medium ionic:20%–40%
General organic sludge:municipal sewage,paper mill,food processing,textile.
High ionic:40%–60%
High-organic sludge:pharmaceutical,fermentation,brewery,oil-bearing sludge,chemical sludge.
2.Select by Molecular Weight
Medium MW:6–10 million
General clarification,belt filter presses,plate-and-frame filters.
High MW:10–15 million
Sludge dewatering under high shear(centrifuge),difficult flocs,high-concentration slurry.
3.Select by pH Value
pH 4–6(weakly acidic)
Use medium–high ionic CPAM.
pH 6–8(neutral)
All types work;medium ionic is most stable.
pH 8–10(weakly alkaline)
Use medium ionic degree.
4.Select by Application
Wastewater clarification
Low–medium ionic,medium molecular weight.
Sludge dewatering
Medium–high ionic,medium–high molecular weight.
Papermaking retention/drainage
Low ionic,low–medium molecular weight.
5.Select by Dewatering Equipment
Centrifuge
High molecular weight,medium–high ionic(shear-resistant flocs).
Belt filter press
Medium molecular weight,medium ionic.
Plate filter press
Medium–low molecular weight,medium ionic.
Screw press
Low–medium ionic,moderate molecular weight.
6.Final Confirmation:Beaker Jar Test
Always test on-site with actual sludge/wastewater:
Prepare 0.1%–0.3%CPAM solutions of different ionic degrees.
Add to sample,stir slowly,observe floc speed,size,clarity.
Choose the grade with best effect at lowest dosage.
References
GB/T 7714
Wang H,Zhang Y,Li S.Selection method of cationic polyacrylamide for water treatment.Industrial Water Treatment,2022,42(5):34–38.
MLA
Wang,H.,Zhang,Y.,&Li,S."Selection Method of Cationic Polyacrylamide for Water Treatment."Industrial Water Treatment,vol.42,no.5,2022,pp.34–38.
APA
Wang,H.,Zhang,Y.,&Li,S.(2022).Selection method of cationic polyacrylamide for water treatment.Industrial Water Treatment,42(5),34–38.
