Sieves​

Size Distribution

Once the sample has been sieved, the material from each sieve is removed and placed into individual containers for solids analysis and settling velocity studies.  Sieving is a key component for separation of grit particles and helps the clients understand the type, and size, of materials entering the grit chamber!

What is a sieve?

A sieve is a mesh strainer that is used to separate material, or in our instance to characterize the particle size distribution of a sample.  The image to the right is a stack of 12 different sieves, all with various sized screens from largest to smallest (top to bottom).  

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Size Distribution

The image to the right shows various sizes of the screen material used to make the sieves.  

The sample is introduced at the top of the sieve stack and then either manually shaken or placed into a sieve shaker.  This allows the particles to settle into the appropriate sieve size....smaller sized particles go through all the larger holes in the top few sieves until it reaches a sieve it can no longer pass through. 

After sieving, particles will now be separated by their size distribution into the various sieves.  Each individual sieve can be removed and the particles on that sieve can be removed and analyzed further.  This allows the user to obtain a general size distribution for the entire sample.