Oil is primarily dispersed through the use of oil dispersants which break oil slicks into smaller droplets.
Understanding Oil Dispersion
Oil spills at sea present a significant environmental challenge. The process of oil dispersion is crucial in mitigating the damage caused by these spills.
The Role of Oil Dispersants
- Lowering Interfacial Tension: Oil dispersants work by reducing the surface tension between oil and water. This reduction in tension allows the oil to break up into smaller droplets (NRC, 2005).
- Accelerated Dispersion: Once broken into smaller droplets, the oil is more easily dispersed into the water column. The increased surface area also accelerates the dissolution of the oil's hydrophobic components.
Why is Dispersion Important?
- Reduced Surface Slicks: Breaking down oil slicks into smaller droplets prevents the formation of a thick layer on the water's surface. This is important for both marine life and coastal regions.
- Increased Biodegradation: Smaller droplets of oil can be more readily biodegraded by microorganisms in the ocean. This natural breakdown is more effective when oil is dispersed.
- Dilution of Concentrated Oil: Dispersion dilutes the concentration of oil in the water column, helping to reduce its immediate toxicity to marine organisms.
How Dispersants Work
- Application: Dispersants are typically applied to oil slicks via ships or aircraft.
- Interaction: The dispersant molecules interact with both the oil and water molecules.
- Breakdown: The result is that the oil slick breaks down into tiny oil droplets.
- Dispersion: These droplets are then dispersed throughout the water column rather than remaining on the surface.
Example of Dispersion
- Imagine a drop of oil in water; without dispersant, it spreads as a slick. With dispersant, it breaks into many tiny droplets. These droplets are more easily moved around by currents, and can be more readily broken down by natural processes.
In summary, oil dispersants play a vital role in dispersing oil by lowering interfacial tension which allows oil slicks to break into smaller droplets and disperse into the water column, facilitating the breakdown of hydrophobic oil components (NRC, 2005).
