Abstract
CaCl2, NaCl, and other byproducts generated by waste treatment are landfilled as fly ash. Cl− dissolved in leachate is discharged to public water, which has an impact on agriculture and marine resources. Therefore, concentrate and dry salt (hereafter referred to as by-product salt) are generated by desalting treatment facilities. This study was conducted on the possibility of recycling by-product salt as a disinfection material for wastewater treatment by generating NaClO and other compounds from it by electrolysis. As a result, a mixture liquid (hereafter referred to as eco hypochlorite) of NaClO and KClO with an effective chlorine concentration of above 5,000 mg / L was generated by a diaphragm-free electrolysis method with the concentration of salt water at 3 % and Ca²＋ at 30 mg / L. In the sterilization capacity test of eco hypochlorite, it was confirmed that its capacity is equal to or greater than that of industrial NaClO. According to the feasibility study, when the amount of dried by-product salt is more than 0.5 t / day (equivalent to the amount of by-product salt generated from a city of 100,000 people) and recycled as disinfection material in a sewage treatment facility, it will provide economic merits to both the source (final disposal site) and the user (sewage).
