The system uses the ocean's own currents to clean up trash
If you haven’t heard, the ocean is one big garbage dump. National Geographic estimates it contains some 5.25 trillion pieces of plastic debris -- 269,000 tons of which floats on the surface. Besides what washes up on the coastlines, the bulk of the trash amasses in five massive “garbage patches” located around the world -- two in the Atlantic, two in the Pacific, and one in the Indian Ocean. Eco-saviors have long been trying to clean things up, but by nature of its sheer size, tackling a clean-up beyond the coastline is untenable. By Boyan Slat's estimation, the most traditional large-scale cleanup strategy -- using boats attached to giant nets while trolling the most polluted areas -- would take about 79,000 years and be incredibly costly.
Slat’s system, alternately, uses the ocean itself as the workhorse, creating what is essentially an autonomous machine. When installed in open water, it functions as an artificial coastline, "catching" the garbage in a V-shaped enclosure as it's pushed along by the ocean's natural currents. The passive system eventually corrals the hordes of floating debris into a concentrated area where it can be easily collected and moved off to shore.
So what happens to all that plastic?
As the trash accumulates in the collection areas, it will need to be hauled off every couple months so it doesn't breach the barriers. To streamline this process, the system is equipped with a solar-powered conveyor belt that slowly feeds the garbage into a giant oil rig-esque bin situated within the collection area, which can be easily emptied by a visiting vessel.
What will they do with all the nasty plastic they pick up? Sell it, duh. Currently, the entire operation relies on sponsorships and donations to keep it up and running, but the ultimate goal is to monetize by selling the extracted plastics back to manufacturers.