insoluble

ratkaisematon

liukenematon That cannot be dissolved.
That cannot be solved; unsolvable; insolvable.
That cannot be explained; mysterious or inexplicable.
That cannot be broken down; dispersed
Any substance that cannot be dissolved.
2006, Ashok Pandey, Enzyme Technology (page 518)

As there is a partial vacuum inside the drum, the liquid is sucked inside the drum and the insolubles are deposited on the outer surface of the membrane filter.