By drying, heating, vacuum drying

A vacuum drying oven is laboratory equipment that dries anything from toothpaste to cosmetics using gentle heat and negative pressure (creating a vacuum.)

Many hardwood floor vacuums offer three options. The first is vacuum, then heated wet vacuum, and then drying. It sort of functions as both a mop and a vacuum.

Under reduced pressure, under carefully controlled conditions, ice sublimes - it goes straight from ice to vapour - no liquid water. It is very useful for drying almost anything, but especially for anything that would be damaged by heating or boiling the water off. That is vacuum freeze drying - the name is often used without the "vacuum" included.