an improved process is provided for the steam conversion of dilute printer ink washup fluids , and especially those of a single color , in order to permit reuse of the ink fraction of the fluids as reconstituted printing inks . preferably , the washup fluids are acidified to create a pin floc therein , with a final ph of from about 2 - 7 ; the acidified fluid is then contacted with a stream of steam in a hydroheater in order to convert the residual ink fraction and permit reconstitution thereof into printing ink . the acidifying agent is preferably an acid polymer or an inorganic acid such as hcl or h 2 so 4 .