| 摘要 |
<p>PURPOSE: To recover an overspray from aqueous coating material and to make the same usable in an industrial scale by maintaining the liquid of an ultrafiltration circuit at a solid content higher than the solid content of the circuit by withdrawing permeate therefrom and using part of the liquid as the aqueous coating material to be sprayed in a spray booth or for preparation of the same. CONSTITUTION: A washing liquid is an aqueous coating material which is diluted with water and is used for spraying in the spray booth 1. The washing liquid in a circuit A consisting of a wet process water spraying wall 8, the bottom 3 of the spray booth 1, piping 9, a pump 10 and an overflow 11 has the approximately constant solid content of 4 to 20 wt.%. The liquid in the ultrafiltration circuit B consisting of a vessel 14, a pump 18, piping 17 having a prefilter 19, an ultrafiltration device 20 and piping 21 is maintained at the solid content which is from 15 wt.% up to the solid content generated by the spraying viscosity of the aqueous coating material and is approximately constant higher than the solid content of the circuit A by withdrawing the permeate. part of the liquid in the ultrafiltration circuit B is used as the aqueous coating material to be sprayed in the spray booth 1 or for preparation of the same.</p> |
