Effect of geometry of hydrodynamically cavitating device on degradation of orange-G

In this research work, we have carried out geometric optimization of different cavitating devices using degradation of orange-G dye |OG| as a model pollutant. Three different cavitating devices viz, orifice plate, circular venturi and slit venturi were optimized and the degradation of orange-G dye was studied. The optimization of all three cavitating devices was done in terms of fluid inlet pressure to the cavitating devices and cavitation number. The effect of pH and initial concentration of the dye on the degradation rate was also studied. The geometry of cavitating device (flow cross sectional area, perimeter, shape, etc.) was found to be an important parameter in getting the maximum cavitational effect using hydrodynamic cavitation. The cavitational yield of all three cavitating devices were compared on the basis of mg of total organic carbon (TOC) reduction per unit energy supplied. The slit venturi gives almost 50% higher degradation rate and cavitational yield among all three cavitating devices studied for the same amount of energy supplied. (C) 2012 Elsevier B.V. All rights reserved.