02647nas a2200265   4500008004100000022001400041245012000055210006900175260000900244300001200253490000800265520177000273653001502043653001702058653001302075653001402088653002502102100001602127700002402143700002102167700002202188700002202210700002502232856012402257       2019                        eng d  a0301-479700aHydrodynamic cavitation using vortex diode: an efficient approach for elimination of pathogenic bacteria from water0 aHydrodynamic cavitation using vortex diode an efficient approach  cJUL   a210-2190 v2423 a<p>The present study successfully demonstrates greener methodology of hydrodynamic cavitation using rotational flows for disinfection of water. Disinfection of two model microbial strains-gram-negative (Escherichia colt) and gram-positive (Staphylococcus aureus) using vortex diode was evaluated. The removal efficacy was quantified for two different cavitation reactors. Practically complete elimination of E. coli was achieved (99%) after 1 h of cavitation at a pressure drop of only 0.5 bar. However, elimination of S. aureus using vortex diode was observed to be lower in comparison to the removal of E. coli and only 60% disinfection could be achieved under similar conditions, which can be subsequently enhanced up to 98% by increasing pressure drop. The results were compared with another cavitating device that employs linear flow for cavitation, orifice. The reactor geometry has significant impact on the disinfection process and orifice was found to require significantly higher pressure drop (10 bar) conditions for disinfection and for eliminating grain-positive bacteria with high efficiency. A plausible mechanism for disinfection was proposed to elucidate the role of cavitation in cell destruction leading to death of cells through the rupture of cell wall, oxidative damage and possible DNA denaturation. Also, a cavitation model using per pass disinfection was developed that can provide meaningful physical description of the disinfection process as against the conventional first order reaction rate model. This study would provide meaningful insight into cavitation process based on hydrodynamic cavitation for the destruction of both gram-negative and gram-positive bacteria from various water sources, including industrial wastewaters.</p>
10aCavitation10aDisinfection10akinetics10apollution10aWastewater treatment1 aJain, Pooja1 aBhandari, Vinay, M.1 aBalapure, Kshama1 aJena, Jyotsnarani1 aRanade, Vivek, V.1 aKilledar, Deepak, J.  uhttps://library.ncl.res.in/content/hydrodynamic-cavitation-using-vortex-diode-efficient-approach-elimination-pathogenic02964nas a2200241   4500008004100000022001400041245012700055210006900182260000800251300001100259490000700270520214700277653001802424653001502442653001702457653000802474653002502482100001902507700002402526700002102550700002202571856012902593       2020                        eng d  a1350-417700aNovel hybrid cavitation process for enhancing and altering rate of disinfection by use of natural oils derived from plants0 aNovel hybrid cavitation process for enhancing and altering rate   cMAR  a1048200 v613 a<p>The present study is an attempt to improvise the hydrodynamic cavitation methodology for effective disinfection of water and also to suggest prototype development for practical application. The enhancement in the disinfection efficiency was evaluated specifically for the effect of pressure, temperature, pH, microbial inoculum size and also on effect of different additives for the two model microbial strains, gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus). The efficacy of the hydrodynamic cavitation is evaluated for the two types of flows/cavitation devices - linear flow in the case of orifice and vortex flow for vortex diode. The vortex diode requires significantly lower pressures, 50% lower as compared to orifice for the similar extent of disinfection. While the bacterial disinfection at high temperature is known, the usefulness of hydrodynamic cavitation is especially evident at ambient conditions and the process is effective even at very high concentrations of bacteria, not reported so far. The reactor geometry also has significant effect on the disinfection. The present study, for the first time, reports possible use of different natural oils such as castor oil, cinnamon oil, eucalyptus oil and clove oil in conjunction with hydrodynamic cavitation. The nature of oil modifies the cavitation behavior and an order of magnitude enhancement in the cavitation rate was observed for the two oils, eucalyptus and clove oil for a very small concentration of 0.1%. The increased rates of disinfection, of the order of 2-4 folds, using oil can drastically reduce the time of operation and consequently reduce cost of disinfection. A possible mechanism is proposed for the effect of oil and hydrodynamic cavitation in cell destruction through the rupture of cell wall, oxidative damage and possible DNA denaturation. A cavitation model using per pass disinfection was used to correlate the data. The increased efficiency using oils and possible benefits of the developed process, where natural oils can be perceived as biocatalysts, can have significant advantages in practical applications.</p>
10aAntimicrobial10aCavitation10aDisinfection10aOil10aWastewater treatment1 aMane, Maya, B.1 aBhandari, Vinay, M.1 aBalapure, Kshama1 aRanade, Vivek, V.  uhttps://library.ncl.res.in/content/novel-hybrid-cavitation-process-enhancing-and-altering-rate-disinfection-use-natural-oils