What is an effective way to remove color from water containing organic materials?

Coagulation is an effective method for removing color from water containing organic materials due to its ability to aggregate small particles into larger clusters. This process involves the addition of chemical coagulants, such as aluminum sulfate or ferric chloride, which destabilize the colloidal and suspended particles in the water. Once these particles are destabilized, they can effectively bind together, forming larger aggregates known as flocs. These flocs are then easier to remove through sedimentation or filtration.

The effectiveness of coagulation in removing color is particularly noteworthy because many organic materials responsible for the coloration in water exist as tiny, colloidal particles. By bringing these particles together, coagulation significantly reduces the intensity of the color, making this method valuable in water treatment processes.

In contrast, while other methods like chlorination, flocculation, and packing filtration have their places in water treatment, they do not specifically target the removal of color with the same efficiency as coagulation. Chlorination primarily aims to disinfect water by killing bacteria and other pathogens, while flocculation is typically used as a follow-up process to coagulation to further enhance the aggregation of particles. Packing filtration is primarily focused on physical removal of particles and might not effectively target the color caused by dissolved organic materials.