Laser Particle Size Analysis


Laser diffraction is a widely used particle sizing technique for materials ranging from hundreds of nanometers up to several millimeters in size.

Laser particle size analysis is critical in determining gravel pack sizes for any formation. Particle size is achieved when particles are passed through dual light sources. Measured particles can range from 0.02 up to 2,000 µm, with size determined as the sample, dispersed in a transport fluid, is circulated through the analyzer.

Main reason for its success:

  • Wide dynamic range - From submicron to the millimeter size range

  • Rapid measurements - Results generated in less than a minute

  • Repeatability - Large numbers of particles are sampled in each measurement

  • High sample throughput - Hundreds of measurements per day

Weatherford Laboratories uses the latest technology in laser diffraction.

A focused red helium-neon laser light for forward, back, and side scattering, and a solid state blue light for wide angle forward and back scattering detects the particles. These particles scatter light at an angle that is inversely proportional to the size of the particle. The angular intensity of the scattered light is then measured by a series of 66 photosensitive detectors. Scattering intensity versus angle data is used to calculate particle size.

Grain-size determination by laser diffraction is essential in reservoir characterization.