Polyacrylamide is used in water treatment:

The amide group of polyacrylamide can have affinity and adsorption with many substances to form hydrogen bonds. High-molecular-weight polyacrylamide forms "bridges" between the adsorbed particles to generate flocs, which is conducive to the sinking of particles. Polyacrylamide type flocculant can adapt to a variety of flocculation phenomena, its dosage is small, the efficiency is high, the generated sludge is less, the post-treatment is easy, and it has special value for some situations. my country's raw water treatment, urban sewage treatment and industrial wastewater treatment industries all use polyacrylamide as a flocculant to varying degrees. Polyacrylamide is currently the most widely used and effective polymer organic synthetic flocculant.

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