A METHOD OF RECOVERING THE OVERSRAY FROM AQUEOUS CA METHOD OF RECOVERING THE OVERSRAY FROM AQUEOUS COATING AGENTS USED IN SPRAY BOOTHS OATING AGENTS USED IN SPRAY BOOTHS

摘要

Herberts Gesellschaft mit beschrankter Haftung A b s t r a c t A method of recovering the overspray from aqueous coating agents applied in spray booths, the overspray being collected in an aqueous washing liquid which is continuously supplied to the spray booth in a circuit (A), a part of the washing liquid containing the overspray being supplied from the circuit (A) to an ultrafiltration circuit (B), and permeate being withdrawn from the ultrafiltration circuit (B) and returned to the circuit (A) to make up the washing liquid, wherein the washing liquid is the aqueous coating agent used for spraying in the booth, after dilution with water, the liquid in the ultrafiltration circuit (B) is the aqueous coating agent used for spraying in the booth, optionally diluted with water, and the process is performed continuously, the washing liquid in circuit (A) having an approximately constant content of solids in the range from 4 - 20 wt.%, and the liquid in the ultrafiltration circuit (B) being kept by withdrawal of permeate at an approximately constant content of solids in the range from 15 wt.% to the content of solids occurring at the spray viscosity of the aqueous coating agent and higher than the content of solids in circuit (A), and a part of the liquid in the ultrafiltration circuit (B) is used as the aqueous coating agent for spraying in the booth, or for preparation thereof. TOTAL P. 21