Experimental Research upon Neutralisation with Ozone of Chemical and Microbiological Pollutants from Sewage Wastewater

The main purpose of the work is to provide practical information regarding the sterilization and reuse of sewagewaters and domestic wastewater, infested with biological and chemical compounds that endanger human health. The research carried out is based on a long experience in the field of sterilization of water infested with pathogenic germs. Water samples were taken from the sewagewater in Cluj-Napoca, containing massive loads of biological micro-pollutants various species of Coliforms, bacilli, bacteria, viruses), specific residues (fats, detergents, cyanides, nitrites, nitrates, sulfur compounds, etc.) that pose severe risks to human health and the environment. To carry out the experiments, the author created an original, versatile experimental stand, which provides a variable voltage source (U = 230V-22 kV), with variable frequency between 1Hz-1 MHz, fed with various waveforms: sine, step, train of pulses, sawtooth, with smooth or fast attack and/or rest ramp. The tests were carried out using two types of electrodes: brush type and with needle discharge tips, for two ozone concentrations: 3g/m3 and 5g/m3. Sample exposure times were 3, 5 and 7 min. The results indicate a total annihilation of microbiological compounds, total reduction of detergents and nitrites and a partial reduction of cyanides. The microbiological and physico-chemical tests were carried out in accredited specialized laboratories.