Study of droplet size distribution during an emulsification process using in situ video probe coupled with an automatic image analysis

Crystallization-in-emulsion process of a melted organic compound: In situ optical monitoring and simultaneous droplet and particle size measurements

“…The stirrer was an axial flow profiled three blade Mixel TT s propeller. This propeller appeared to be a better multipurpose stirrer than a radial flow Rushton turbine, since it had almost the same performance during the emulsification stage [28] and it was recommended for ensuring efficient liquid-solid homogenization during the crystallization stage [31].…”

“…The first stage of the process consists of the dispersion of a molten organic material in water in the presence of emulsifiers leading to an oil-in-water (O/W) emulsion. The stirring conditions and the amount of emulsifier used allow the control of the distributions of droplet sizes [28]. Crystallization upon cooling is the second stage, the emulsion being progressively converted into a suspension of solid particles.…”

Review on Measurement Techniques for Drop Size Distribution in a Stirred Vessel

“…Hough transformation is then applied to identify the contour of the drops in the image for different values of the radius. Another approach by Khalil et al 34 involves detection of drops' circular patterns by use of Hough transformation and conversion into circles. The radii of the circles are calculated by computing the signature curve for each circle identified in the image and then matching it with a standard signature curve of a circle.…”

“…The automatic image analysis system developed by Khalil et al 34 has a mean error of 10.3% based on image resolution of 2.0 μm/pixel. The accuracy was considered to be satisfactory but the analysis process for 300 frames required about 40 min, which is too large to allow real-time image analysis and DSD calculation during an experiment.…”

“…A visual probe is commonly, used and it is trusted as a reliable technique wherein it allows direct visual observation of the dispersion process. 34 The main instruments in this technique are camera, microscope, and illumination setup. A different type of camera can be used such as a charge-coupled device (CCD) camera, a high-speed camera, or a video camera.…”