Powdered flocculants prepared by using evaporative cooling to coat polymeric materials on a porous substrate

摘要

The invention is a polymeric powder that is useful as a flocculant and an associated process for preparing the same. The powder is prepared from spraying a liquid containing a water-soluble polymer into a fluidized bed of porous substrate particles. The spraying process coats the polymer onto the substate and removes the water through evaporative cooling. Polymeric powders prepared according to the invention rapidly dissolve in water and have improved viscosities over thermally dried polymer powders. Polymers that are useful in the invention include polyacrylamides, polyamines, and the like. The substrate is a porous material that can be either organic or inorganic, and typically has a porosity from about 1 to 1,000 m²/g.