| 초록 |
In general, used foundry sand was regenerated by physical and thermal methods but the chemical regeneration has been also studied recently. The wastewater generated from chemical regeneration process was treated using the coagulant. The aim of this study was to investigate the optimum coagulation/flocculation condition by adjusting the pH value of the wastewater after adding the coagulant. The pH value was controlled between 3 and 12 using 1 M H2SO4. After the coagulant was added, it was mixed for 3 min under rapid mixing condition at 300 rpm using stirrer. The solution was slowly mixed for 15 min at 50 rpm. After settling for 30 min, the supernatant was withdrawn to measure COD and Zeta potential using UV-vis spectrophotometer and Zeta potential analyzer, respectively. |
