The term “ultra” is a modifier that is thrown around haphazardly to enhance the meaning of virtually any phrase. But when it’s attached to filtration, as in ultra filtration, it distinctly alters the meaning. In ultra filtration, hydrostatic pressure is used to force a liquid through a semipermeable membrane, effectively removing large molecules from the solution.
You’re probably asking yourself, “Who actually does this?” Typically the process is used to purify and concentrate protein solutions, such as those used in the dairy industry. The only difference between this and other types of filtration is the size of the molecules that are removed from the liquid.