The effect of "Hydrogen peroxide- Silver ion Complex" on fecal coliform content in aerated lagoon Effluent

An appropriate disinfectant in water and wastewater applications must have acceptable effect on different kind of micro-organisms especially in minor concentrations which should contain ignorable toxicity on human and animals and its environmental side effects must be very low. Studies related to finding non-chlorinated disinfectants which have same effects of chlorine and not contain its adverse by-products are continued in recent years. Hydrogen peroxide solution with stabilized formulation and oligo-dynamic amounts of silver ion (trade mark: Nanosil) recently become a popular disinfectant for fruits, vegetables, surfaces, medical instruments and disinfections. This study was based on determining removal efficiency of fecal coliforms from samples taken from Qom wastewater treatment plant effluents after exposing with hydrogen peroxide-silver ion complex. Disinfectant efficiency was studied in six concentrations. Contact time for all concentrations was one hour. Sample size was 12 and sampling was daily. Results reveal that in concentration; 80mg/l, disinfectant achieves 2.1 logarithmic removals of fecal coliforms. In concentration; 480mg/l, fecal coliforms logarithmic removal was 5.3. In CT value 5800(mg/l). Min and more, the fecal coliforms effluent standard for surface water discharge and agriculture irrigation was achieved (Iranian environmental protection agency act).Use of hydrogen peroxide-silver ion complex as a water and wastewater disinfectant, has various benefits such as; dont remain hazardous by products, measurable residual amount an but because of its oxidation nature when contact the organic materials in wastewater and microbial harboring in suspended solids content of effluent, its application in wastewater effluent is more costly than other usual disinfectants.