Reduced Waste

All solvents have a temperature threshold; when heated above this temperature, they begin to break down and become ineffective. The contaminant concentration that atmospheric distillation can reach is therefore limited to the boiling point of the contaminant-solvent mixture, which requires a temperature at which the solvent begins to break down. For trichloroethylene, for instance, the critical temperature is around 220 F.

  The curve shows the boiling points of trichloroethylene for increasing oil concentrations. Open-top vapor degreaser manufacturers recommend distilling until reaching around 35%, at which point the mixture would require a temperature of 217 F.

  Vacuum systems keep reducing the pressure to concentrate contaminants. Concentrations from 70 to 95% oil are commonly attained. The savings are two-fold. The more solvent recovered, the less solvent needs to be purchased, and the less waste disposal is required. This can be very economical when specialty solvents are being used. All of our Vacuum Processing Solvent Systems come with onboard vacuum distillation.