Chemical Reactor Flow Characterization by Laser Diffraction

2 Chemical Reactor Flow Characterization by Laser Diffraction 

The laser diffraction particle sizer techniques have been used to measure spherical solid particle and droplet size distributions in dilute dispersions located in chemical reactor and separation equipment. 

Setekleiv and Svendsen [180] used the same laser difliraction particle sizer to characterize the ability of mesh pads to separate droplets from the gas stream in a scrubber. Droplets in the size range 30-1000 p,m with a bi-modal distribution was obtained at low pressure. A rough sketch of the mounting of the laser diffraction instrument used in this work is shown in Fig. 13.17. Numerous applications of the LD particle sizer for solid particle size distribution measurements characterizing aerosols and suspensions can be found in the literature. Only a few examples of laser diffraction solid particle size distribution measurements relevant for fluidized bed system characterization are mentioned in this report. Garea et al. [71] measured the solid sorbent particle size distribution in a fluidized bed in-duct desulfurization reactor under in-duct conditions by laser diffraction. Ferrer et al. [66] studied fluidized bed combustion of refuse-derived fuel in presence of protective coal ash and measured the fly ash particle size distribution with a laser diffraction method. Tanneur et al. [192] measured the solid particle size distribution in a fluidized bed by use of a diffraction particle size analyzer. 

In a couple of particular papers, the application of LD particle sizer to measure the size distribution of micro-bubbles are mentioned. Couto et al. [44] performed micro-bubble size distribution measurements by the laser diffraction technique. It was concluded that the size distribution of micro-bubbles generated for the dissolved air flotation process could be assessed on a fast and reliable way by the application of the laser diffraction technique. The micro-bubble size distribution was measured by the Mastersizer 2000 SM equipment from Malvern Instruments, UK. The instrument specifications state that analysis in the particle range from 0.1 to 2000 ttm is possible, and the data interpretation computations could either be performed by use of the 

---