Lubrizol has completed its acquisition of the additives business of Avecia, headquartered in Blackley, U.K., comprising pigment dispersants marketed under the brand names Solsperse, Solplus and Solthix.      In 2003, Avecia Additives had revenues of approximately $50 million. Lubrizol has begun to integrate this business into its existing $100 million paints, coatings and inks additives business unit within the fluid technologies for industry (FTI) segment.          The acquisition complement...