It’s called the Base Salvage Capsule. All items from a deleted base should be going in there if you have one. However, I have not seen it go into one placed on a freighter for some reason. Maybe that was supposed to work or for freighters only. So far, besides aesthetics, I have found it useless on a freighter though.
Note: I am not sure if you get the full amount or only 50% as it used to be in Atlas Rises. Maybe someone else can confirm. I have so far always deleted the most expensive parts manually, to then leave the rest to this machine. Usually ended up getting just the Carbon, Ferrite and alike back, but never been bothered to count.
When I was doing research to find the building limits, I used ‘Wooden Half Ramps’ and ‘Small Wood Panels’. You can then build up in a circular fashion, place ramp, panel then rotate 90° rinse repeat …
Keep in mind there are limits. One limit is the distance from the Base Computer, another is a part count. Also keep in mind that from my experience, about 1150u - 1200u is the in-game allowed height limit. Without cheating, anything beyond (upto 2000u) will be deleted with a reload.
For further details and video see my post here: