Hot synthesis gas is cooled and deashed by passage through first zone in contact with a downwardly descending film of cooling liquid, a second zone in contact with a spray of cooling liquid, a third zone in contact with a body of cooling liquid, and a fourth zone in contact with a spray of cooling liquid--at least a portion of the cooling liquid to the first zone preferably being recycled cooling liquid from which at least a portion of the solids contained therein has been removed.