The Chemical Mechanism of Coagulation
Coagulation is a chemical process that occurs in the initial phase of water treatment. Most particles suspended in water, such as clay, bacteria, and organic matter, possess a negative surface charge. Because like charges repel, these particles remain in a stable, suspended state, creating "turbidity" or cloudiness.
Charge Neutralization: Coagulants are positively charged chemicals (typically metallic salts like Aluminum Sulfate or Ferric Chloride) that, when added to water, neutralize the negative charges of the suspended particles.
Rapid Mixing: To be effective, coagulants require high-energy, rapid mixing (flash mixing). This ensures the chemical is distributed instantly, allowing the neutralized particles to collide and form submicroscopic clumps known as micro-flocs.
2026 Innovation: The move toward Organic Coagulants (such as PolyDADMAC) has gained traction because they do not alter the water's pH and produce significantly less sludge compared to traditional inorganic salts.