Film fraction in a vertical circular Venturi scrubber

The liquid film affects significantly the Venturi scrubber efficiency. Film fraction was measured in a vertically mounted laboratory scale Venturi scrubber with a 0.020 m throat diameter. The liquid was injected at the throat by one to six 0.001 m holes. The throat gas velocity varied from 50 to 90 m/s and the relative jet penetration varied between 0.05 and 0.85. A special test section with a slot was used to extract the film. The test section could be placed at different axial positions, allowing measurements at 0.0075, 0.0275 and 0.0675 m after the injection point. Results showed that film fraction varies as a function of the relative jet penetration and with distance from the injection point. There exists an optimal relative jet penetration (between 0.25 and 0.40) which minimizes film fraction. Film fraction increased with axial distance in the range studied, up to 3.375 throat diameters after the injection point.