Types of Crude Oil: Light vs. Heavy
Light Crude Oil
- Definition: A type of liquid petroleum with low density and high API gravity.
- Flow Characteristics: Flows easily at room temperature due to low viscosity.
- Key Properties:
- High proportion of light hydrocarbon fractions
- Low specific gravity
- Low wax content
- API gravity: Typically above 31.1°
- Refining Advantage: Yields more high-value products like gasoline and diesel.
Heavy Crude Oil
- Definition: Petroleum with high density and low API gravity.
- Flow Characteristics: Does not flow easily, often requires heating or dilution.
- Key Properties:
- Higher viscosity and specific gravity
- Often contains more impurities (e.g., sulfur, metals)
- API gravity: Less than 20°
Extra Heavy Crude Oil
- Definition: A denser subset of heavy crude oil.
- API gravity: Less than 10°
- Behavior: Sinks in water due to high density.
Note on API Gravity:
- API > 10 → Floats on water
- API < 10 → Sinks in water
Light crude oil receives a higher price than heavy crude oil on commodity markets because it produces a higher percentage of gasoline and diesel fuel when converted into products by an oil refinery. Heavy crude oil has more negative impact on the environment than its light counterpart since its refinement requires the use of more advanced techniques an the use of contaminants.
Specifications
| Property | Measured | Blended Back |
|---|---|---|
| API Gravity | 35.4 | 35.8 |
| Specific Gravity (SG) | 0.8478 | 0.8459 |
| Sulfur (wt%) | 0.14 | 0.14 |
| Hydrogen (wt%) | – | 13.2 |
| Total Nitrogen (ppm) | – | 1030 |
| Acid Number (mg KOH/g) | 0.27 | 0.25 |
| Pour Point (°F / °C) | 0 / -18 | 0 / -18 |
| Characterization Factor (K) | – | 11.9 |
| Viscosity @ 40°C (cSt) | 3.14 | – |
| Viscosity @ 50°C (cSt) | 2.90 | 2.90 |
| Vanadium (ppm) | – | 0.4 |
| Nickel (ppm) | – | 3.6 |
| MCR (Micro Carbon Residue, wt%) | – | 0.99 |
| Ramsbottom Carbon (wt%) | – | 0.93 |
| Asphaltenes (H.C7, wt%) | – | 0.007 |
