Coagulants refer to the general term for agents added during the process of agglomeration of unstable colloidal particles (or particles formed during the coagulation process) to form aggregates. Coagulants, including high-molecular-weight coagulants and flocculants, can disrupt the stability of colloidal particles in water, reduce their mutual repulsion, and thus form fine flocs, achieving solid-liquid separation and purifying water quality. Used for the treatment of metalworking wastewater, meat processing wastewater, phosphorus-containing wastewater, fluorine-containing wastewater, papermaking wastewater, and coal gas washing water.