Particle Size Separation Methods Quiz

Particle Size Separation

• The classification of particles into separate ranges of size
• The removal of particles from gases or liquids

Size Separation Methods

Sieving

• Similar to particle size analysis, but utilizes larger sieves
• Sieves should be resistant to chemical action, stainless steel is recommended
• Can be done by dry or wet sieving

Dry Sieving Techniques

• Agitation methods use vibrations to facilitate particle passage through pores. Gyration is another method that uses rotation to reorient particles
• Brushing methods utilize a brush to reorientate particles on the sieve's surface, preventing pore blockage
• Centrifugal methods utilize high-speed rotors and forced air to separate particles

Wet Sieving

• More efficient than dry sieving

Size Separation By Fluid Classification

Sedimentation Methods

• Gravitational methods use chambers containing a suspension of particles in a liquid. After a predetermined time, particles of a specific size are removed.
• Continuous settling chamber employs a shallow container with a driving force. The force is divided, one component is horizontal due to particle velocity, the other is vertical due to gravity. Sedimentation occurs with the coarsest particles closest to the inlet and finest furthest from the inlet.

Centrifugal Methods

• Centrifugal methods increase the driving force of sedimentation, separating particles by size using cylindrical or multiple chamber centrifuges

Elutriation Methods

• Elutriation uses fluids flowing in the opposite direction of sedimentation to separate particles. The velocity of the fluid dictates the size fraction.
• Upward airflow elutriator classifies particles based on their ability to be carried upward by airflow.
• Multistage elutriators utilize a series of columns with increasing diameters. The fluid velocity decreases as the diameter increases, separating various particle sizes.

Cyclone Methods

• Reverse-flow cyclone is a common method for separating particles from fluid streams.
• The fluid velocity creates a vortex that forces particles outward.
• The conical section forces particles downward, and finer particles leave with the fluid through the vortex finder.

Test your knowledge on various particle size separation methods including sieving techniques, wet and dry sieving, and sedimentation methods. Learn about the principles behind these techniques and explore their applications in different fields. This quiz is perfect for students and professionals in materials science and engineering.