The existing means of fighting marine pollution

Looking at the way major oil spills are managed, we noticed that very little amounts of hydrocarbons are collected at sea. Actually, most quantity is collected when it lands on the shoreline, creating dramatic environmental issues as we all know.

Ports and coastline

Solid waste are mainly collected by ships equipped with baskets. In order to operate, these boats need to sail through the polluted area, which makes them inappropriate for cleaning confined spaces, where pollution usually gathers. Liquid waste used to be recovered by conveyor belts, pumps or brushes. Considering oil thicknesses, these systems can appear completely inoperative and are furthermore unable to access narrow places.

Coastline

Vessels cleaning liquid pollution have a very limited recovery rate. Those in charge of solid waste are able to collect only that type of material.

Open water

Most spill response vessels are not primarily designed for cleanup operations. The vessels are provided with sweeping arms and with pumps connected to skimmers.

They sail into the slick with their arms deployed in order to increase the oil thickness :

Pumping the hydrocarbons with skimmers induces an emulsification between the water and the hydrocarbons. This emulsion contains up to 80 percent water.

The emulsion recovered cannot be stored directly in tanks as the volume is too great, and has to be heated in order to separate the hydrocarbons from the water. The time required for heating the emulsion is the real rate of collection. The vessels cannot recover continuously, and their collection capacity is very low, whatever the power of their pumps.

This recovery system will actually only work up to Beaufort Force 3...

Using sweeping arms limits the speed under 1.5 knots because the system does not support a higher speed and to avoid divergence created by the bow wave. At this speed the rudder of a ship is inoperative from Beaufort Force 3.

This limits the navigation to a calm sea state.

Too little hydrocarbon is recovered from the water