For several reasons, the manufacturing industry is progressively moving away from solvent based coatings to water based coatings. The Automotive industry is a prime example. But the so-called water-based technologies are not entirely free of organic solvents. The wastewater from the coating step is a complex mixture of water, inorganic pigments, resins, and co-solvents that is expensive to dispose.
Pass-through Distillation could remove the water and co-solvents from the mixture leaving a reduced volume for incineration. Conventional distillation would not work because high temperatures would cause fouling on the heat exchange surfaces. PTD’s low temperature operation would prevent that.