title: Combined physico-chemical treatment of secondary settled municipal wastewater in a multifunctional reactor.
abstract: In this paper, the physico-chemical treatment of municipal wastewater for the simultaneous removal of pollutant indicators (chemical oxygen demand (COD) and total coliforms) and organic contaminants (total phenols) was investigated and assessed. A secondary settled effluent was subjected to coagulation, disinfection and absorption in a multifunctional reactor by dosing, simultaneously, aluminum polychloride (dose range: 0-150 μL/L), natural zeolites (dose range: 0-150 mg/L), sodium hypochlorite (dose range: 0-7.5 mg/L) and powder activated carbon (dose range: 0-30 mg/L). The treatment process was optimized using computational fluid dynamics (CFD) and response surface methodology. Specifically, a Latin square technique was employed to generate 16 combinations of treating agent types and concentrations which were pilot tested on an 8 m(3)/h multifunctional reactor fed by a secondary effluent with COD and total coliform concentrations ranging from ≈20 to 120 mg/L and from 10(5) to 10(6) CFU/100 mL, respectively. Results were promising, indicating that removal yields up to 71% in COD and 5.4 log in total coliforms were obtained using an optimal combination of aluminum polychloride (dose range ≈ 84-106 μL/L), powder activated carbon ≈ 5 mg/L, natural zeolite (dose range ≈ 34-70 mg/L) and sodium hypochlorite (dose range ≈ 3.4-5.6 mg/L), with all treating agents playing a statistically significant role in determining the overall treatment performance. Remarkably, the combined process was also able to remove ≈ 50% of total phenols, a micropollutant known to be recalcitrant to conventional wastewater treatments.
authors.affiliation: AquaSoil Srl, Fasano (Br), 72015, Italy.
authors.forename: O
authors.initials: O
authors.lastname: Santoro
authors.forename: T
authors.initials: T
authors.lastname: Pastore
authors.forename: D
authors.initials: D
authors.lastname: Santoro
authors.forename: F
authors.initials: F
authors.lastname: Crapulli
authors.forename: M
authors.initials: M
authors.lastname: Raisee
authors.forename: M
authors.initials: M
authors.lastname: Moghaddami
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry; D057919:Biological Oxygen Demand Analysis; D003198:Computer Simulation; D004203:Disinfection; D004755:Enterobacteriaceae; D004867:Equipment Design; D010865:Pilot Projects; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods*; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology; D017641:Zeolites
chemical_list: D017607:Aluminum Compounds; D062065:Wastewater; D017641:Zeolites