The document discusses coagulation and flocculation as a water treatment process. Coagulation involves adding positively charged chemicals to destabilize negatively charged particles in water by neutralizing their charge. Flocculation then occurs, where the destabilized particles collide and form larger flocs that are more easily removed by sedimentation or filtration. Common coagulants used are metal salts like aluminum and iron salts, as well as organic polymers. The overall process destabilizes particles, increases their size into flocs, and then separates the flocs physically from the water.