Laser diffraction particle counter

Principle of operation of a laser diffraction particle counter. 

Particle size Laser diffraction Coulter counter Photon correlation spectroscopy Microscopy Ro-Tap sieve analysis... 

For a given bulk solid, determine particle size distribution, median particle diameter dv50 (e.g., using a Coulter Counter or a Malvern Laser Diffraction Analyser) and ps. 

We will not dwell further on this method since electrical conductivity, i.e.- Coulter Counter and optical methods, i.e.- Laser-Diffraction have totally supplanted all of the sedimentation methods for determining particle sizes. 

Multiple techniques can be used to measure the particle size distribution, for example electrozone sensing, sedimentation, laser diffraction, and microscopy. With the exception of microscopy, they all require calibration and the results depend on the technique. For example, in a round-robin study reported in Reference 4, the commonly used electrical sensing zone technique (Coulter Counter) was compared to microscopy and sedimentation. The average particle size determined by the electrical sensing zone method was by about 25%... 

Keywords texture, particle size, shq>e, fabric, laser diffraction. X-ray attenuation, sedimentation, particle counter, grain size distribution... 

An optical microscope, a standard set of sieves, an Andreasen Pipette, and any versatile instrumental particle sizer, such as a laser diffraction equipment or an electrical sensing zone particle counter. 

An instrumental particle size analyzer, such as a laser diffraction or electro sensing zone counter, will be appropriate options for measuring particle size distributions. A rotational viscometer will be used to measure apparent viscosity if the suspension results are non-Newtonian. 

Figure 7.11. Comparison of results obtained by Palmer, using laser diffraction and resistazone stream counter for fineparticles of various shapes, a) Results for spherical latex fineparticles. b) Results for spherical diamond dust with some cubic fineparticles. c) Results for plate-like fineparticles. d) Results for rod-shaped particles. (Micrographs and data used by permission of American Laboratory and, J. Cowley, T. Palmer and P. J. Logiudice [4l].)...

---