What is a common sign of inadequate mixing in the coagulation process?

Inadequate mixing during the coagulation process can lead to the formation of large flocs, which is a sign that the process is not functioning optimally. When coagulants are added to water, they must be thoroughly mixed to ensure that they can effectively destabilize the particles suspended in the water and promote the aggregation of smaller flocs into larger ones.

If mixing is insufficient, it can result in a situation where particles do not come into effective contact with the coagulant, which prevents the formation of a uniform and stable floc. Instead, larger clusters may form because some particles might interact poorly with the coagulant, leading to an imbalance in the coagulation reaction. This results in a non-uniform distribution of floc, causing the created flocs to grow too large in certain areas, rather than a consistent size that's optimal for sedimentation.

Other symptoms of poor mixing can lead to various inefficiencies in the coagulation process, but the identification of large flocs is a direct indicator that the mixing has not occurred adequately, thus signaling potential issues that may need to be addressed for effective water treatment.