... there are some waste impurities, gas contents in the transformer oil which destroy the oils quality. Our Series ZYD Double-stage vacuum ... , oil filter, oil process, oil purify,oil regenerating, oil restoration, waste oil disposal, oil reclaimed) Technical Parameters: ParametersUnitZYD-30ZYD-50ZYD-100ZYD ... ≤0.5 (no free carbon) Vacuum transformer oil purification equipment series ZYD