Video

Key points TMC’s collector weighs about 90 tons in air but only 15 tons on the seafloor with buoyancy applied, and post-pass surveys showed disturbance of just a few centimeters, versus roughly 80 cm of sediment churning from the older Archimedes screw design. The Coanda nozzle intake…

Key points Hydrophone monitoring found noise above 120 decibels, the U.S. National Marine Fishery Service threshold for a cetacean behavioral response, extends about 3.6 km around the production vessel. The main noise source is the vessel’s dynamic positioning thrusters, not seismic…

Key points TMC found that sediment plumes form turbidity currents that follow the seabed’s contours and flow downslope into depressions, letting engineers predict where sediment will settle with high accuracy. The original straight-line mine plan required 80 to 100 km runs with the…

Key points TMC’s commercial system adds a hydrocyclone step to the dewatering process to filter out abraded nodule fragments below one millimeter, so the return water consists of sediment and water only. Separated sediment is released through a return pipe at a depth of 2,000 meters, a…

Key points Allseas’ diffuser system releases excess water used in nodule collection back into the environment, returning up to 95% of entrained sediment at the diffuser level before it can enter the riser system. The diffuser slows and concentrates the exiting flow, promoting formation…

Key points Inside the collector vehicle, nodules and sediment pass through pumps into a hopper, where differential flow rates tumble the nodules so sediment separates from them at the seabed. Because nodules are heavier, they sink to the bottom of the hopper while 95-98% of sediment…

Key points The video shows the Glomar Explorer now carrying an advanced-design robot miner, ready for testing. TMC says nodule deposits can be found and estimated without extensive prospecting, using sonar and TV imaging. Fifty years after nodule collection technology was first pioneered,…