Question

Difference between sieving and filtration

Answer 1

A sieve sets a threshold calibration through which all undersized materials pass through. A filter separates materials with one quality from materials without that quality - size, phase, reactivity, polarity, etc. 

Long answer: Filtration differs from sieving, where separation occurs at a single perforated layer (a sieve). In sieving, particles that are too big to pass through the holes of the sieve are retained (see particle size distribution). In filtration, a multilayer lattice retains those particles that are unable to follow the tortuous channels of the filter. Oversize particles may form a cake layer on top of the filter and may also block the filter lattice, preventing the fluid phase from crossing the filter (blinding). Commercially, the term filter is applied to membranes where the separation lattice is so thin that the surface becomes the main zone of particle separation, even though these products might be described as sieves.

Answer 2

The differences between two separation techniques - sieving and filtration are:

Explanation

SEPARATION TECHNIQUES -

1. SIEVING

• A method of separation of solid particles from an impure mixture.
• Separation is done based on the different sizes of the particles.
• In sieving, small-sized particles drain out of the holes and the larger particles are separated out.
• Example - Separation of dust particles, sand, and gravel from grains.

2. FILTRATION

• A technique to separate solid from liquid or gaseous mixture.
• The filters used for separation can be biological, physical, or mechanical.
• The filter traps the solid impurities and separates out the filtrate.
• Example - Separation of sand from water.