Chemical Engineering Transactions (Nov 2022)
Energy Efficiency in Bacterial Treatment of Wastewater by Hydrodynamic Cavitation
Abstract
Helping energy consumers to make the best decision in the use of energy is essential to save it, as well as to take advantage of it conveniently. There are many wastewaters treatment processes that generate negative impacts on the environment and it is necessary to require new forms of treatment, seeking to mitigate said impacts; Thus, in recent years, a physical phenomenon considered harmful has been taken into account, but now it is sought to take advantage of it positively to decontaminate and improve the quality of surface and waste water, we refer to hydrodynamic cavitation. Hydrodynamic cavitation in water treatment is a technology that is on the rise due to its environmental advantages as it does not use chemical products as is done with some traditional methods. Given the question about the energy consumption necessary to generate hydrodynamic cavitation in the bacterial disinfection of wastewater, the research aimed to determine the energy efficiency for each unit of energy in the reduction of the "microbiological load" parameter presented by domestic wastewater, during the treatment time. The result, after 80 minutes, using cavitation equipment that operated with a 3.37 kWh pump, the energy efficiency was found to be the elimination of 2,344 MPN of bacteria for each joule consumed; In addition, the value of the microbiological parameter was within the maximum permissible limits established by the Peruvian environmental authority. Therefore, hydrodynamic cavitation turns out to be a possibility for the treatment of bacteria in domestic effluents, it does not generate polluting residues, it has low energy consumption and probably low economic cost; In parallel, other physicochemical parameters also imp