VIKRANT GAIKWAD, SHIKHA GAIKWAD1 AND VIVEK RANADE
Abstract
Hydrodynamic cavitation offers distinct advantages for water disinfection and waste water treatment particularly at large scales of operations. For applying hydrodynamic cavitation for water disinfection/ treatment, water stream to be treated is passed through a fluidic device in which there exists a low pressure region. Cavities are generated in this region when the pressure falls below vapour pressure (in absence of any dissolved gases). These cavities are then collapsed when they travel to regions of higher pressure and lead to very high shear, temperatures and pressures in localized regions. These high pressure/ temperature as well as high shear facilitate disinfection as well as reduction in chemical oxygen demand, colour and amonical nitrogen in the water. In this work, we have investigated hydrodynamic cavitation generated by five different orifices have been studied which have different shapes with same fractional open area and have tested their effectiveness for water disinfection. The efficacy of generated cavitation on water disinfection was quantified based on measurements of non-pathogenic E. coli colony forming units (CFU/mL). The presented results and analysis will be useful for designing hydrodynamic cavitations based systems for water disinfection.