Treatment of Bathing Seawater by Combined Processes Including Chemical Coagulation, Ozonation and Granular Activated Carbon Adsorption

This study was conducted to investigate whether the physical-chemical process of combined chemical coagulation, ozonation and granular activated carbon (GAC) adsorption was an efficient method for the treatment of bathing seawater. In coagulation experiments, The effects of pH and aluminum sulphate (Al-2(SO4)(3)) dosage on the removal efficiency for bathing seawater were discussed. At the optimal pH of 7.0 and coagulant dosage of 50mg/L, the removal efficiency of turbidity, LAS and CODCr were 88.2%, 68.0% and 41.2%, respectively. The ozonation and adsorption experiments suggested that LAS concentration of bathing seawater was reduced to less than 0.3mg/L under in 30min of ozonation time and 24h contact time of GAC adsorption. Infrared and GC-MS results revealed that the ozonation can attack the aromatic ring and transform higher molecular weight LAS to lower molecular weight by products that are more easily absorbed by granular activated carbon.