How do polyelectrolytes work in the context of water treatment?

Polyelectrolytes are macromolecules that carry a charge and play a crucial role in water treatment processes. Their primary function is to enhance particle aggregation, which is an essential step in the clarification of water. When added to water, polyelectrolytes can effectively destabilize colloidal particles by neutralizing the repulsive forces between them. This leads to the formation of larger aggregates or flocs, making it easier for these particles to settle out of the water during sedimentation or to be removed during filtration.

This process is particularly beneficial in the treatment of wastewater or surface water, where suspended solids, organic matter, and other contaminants can be effectively removed by the aggregation process. Enhanced particle aggregation leads to clearer water and improved removal of undesired substances, making this technique a cornerstone in water treatment operations.

The other options do not accurately capture the primary function of polyelectrolytes in water treatment. While they play various supportive roles in different contexts, enhancing particle aggregation is the most significant and well-documented effect of polyelectrolytes in this field.