Segregation Coefficient
Definition
The Segregation Coefficient (S), also called the Segregation Ratio, measures how evenly components are distributed in a mixture. It is commonly used in materials science and soil mechanics.
1. In Materials / Powder Technology
- Used for mixing powders or granules.
- Indicates uniformity of a mixture.
- Occurs when larger/heavier particles settle faster than smaller ones.
Formula:
S = Concentration at top layer / Concentration in bulk mixture
- S = 1: No segregation (uniform mixture)
- S > 1: Component concentrates at top
- S < 1: Component concentrates at bottom
Applications: Pharmaceuticals, food grains, construction materials
2. In Soil Mechanics
- Measures how soil particles separate when poured or compacted.
- Larger or denser particles settle faster, causing uneven composition.
- Helps design mixers and processes to maintain uniformity.
Summary Table
| Parameter | Meaning | Ideal Value |
|---|---|---|
| S (Segregation Coefficient) | Ratio of component concentration at top vs bulk | 1 (no segregation) |
| S > 1 | Component concentrates at top | Not ideal |
| S < 1 | Component concentrates at bottom | Not ideal |
Segregation Coefficient quantifies how evenly a mixture is distributed and helps engineers maintain quality control in powders, grains, concrete, or particulate materials.