Effect of Dissolved Air Flotation Process on Thickening of Activated Sludge

Aims: Sludge is an inescapable component of all wastewaters that originatedfrom their treatment. dissolved air flotation (DAF) process as an alternativeclarifier is used in treatment of drinking water, pretreatment of wastewater,and as a phase separator in sludge activation processes. This study aimed tocalibrated the usage of DAF process in a laboratory scale and under variousconditions, to achieve the optimum efficiency in recycling the activated sludge.Instrument & Methods: In this experimental study, of Kashan s ShahidBeheshti hospital and immediately transported to the laboratory. The optimaldose of polyaluminum chloride coagulant and pH was determined and thenapplied in DAF process. Finally turbidity, electrical conductivity (EC) and totalsolids (TS) parameters were measured and compared with control sample.Findings: The optimal pH and optimal dose of coagulant were 6.5 and 25mg/l,respectively. Also Optimal process efficiency to reduce EC, TS and turbidityparameters were 23.4, 44.5 and 88%, respectively.Conclusion: Dissolved air flotation process removes the turbidity, EC and TSeffectively; however, it has minimal impact on EC and TS.

کلیدواژه ها:

Dissolved Air Flotation [Not in MeSH] ، Hospitals [https://www.ncbi.nlm.nih.gov/mesh/68006761] ، Recycling [https://www.ncbi.nlm.nih.gov/mesh/68059027] ، Sludge [https://www.ncbi.nlm.nih.gov/mesh/68012722]