A process for removing solids from a water-based flush solution, The process includes: providing dirty flush solution; directing the dirty flush solution to a treatment vessel; adding one or more chemicals to the treatment vessel to form a treated flush solution; separating aggregated paint compounds from the treated flush solution to form a filtered flush solution; and directing the filtered flush solution to spray application equipment. The flush system of the invention includes a treatment vessel, wherein the dirty flush solution is mixed with one or more chemicals to form a treated flush solution; a primary separation unit to remove particles including aggregated paint compounds from the treated flush solution to form a filtered flush solution; and transfer lines to direct the filtered flush solution to spray application equipment. The filtered flush solution contains: 1% to 5% by weight of a water soluble organic solvent; 0.08% to 2% by weight of an alkaline agent selected from an amine or an alkanolamine; 0.2% to 1.5% by weight of polypropylene glycol; 0.3% to 2.5% by weight of alkoxyethanol; and water.