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Experimental methods and results
The group in attempt to recreate surface foam in a lab setting, similar to that found in AguaClara Plants in Honduras and to determine the cause of the foam formation applied a rapid mix testing under different parameters. The parameters include Aluminum Sulfate (Alum) dosage, concentration of Natural Organic Matter (NOM) such as Humic Acid, location of alum addition, aeration of water and addition of a surfactant. In the first week of our experiment, we tested for alum dosage in order to determine whether it caused foam formation. Alum dosages of 35 mg/L, 45 mg/L, 55 mg/L and 65 mg/L were added to the rapid mix chamber. It resulted in no foam formation in rapid mix chamber or in the first baffle.
The following week the group used humic acid in order to determine the effects of organic natural matter on surface foam formation. Varying the dosage at 1mg/L, 2mg/L, 5 mg/L and 10 mg/L, humic acid was mixed in the rapid mix chamber with alum. In the mean time the water in the first baffle was being aerated. Soon after, bubbles started forming. The formation of bubbles increased as the concentration of humic acid was increased. However, the bubbles dissipate quickly and were unable to form foam. The group observing the property of the bubbles added soap, a surfactant, to the rapid mix chamber. This resulted in a higher bubble formation, which lasted for a while forming a chain of bubbles over the surface of the water. **brief explanation of the experiment after the experiment summary***