The unique “SOFTBLEACH” bleaching system gently removes residual phosphatides, metals, soaps and oxidation products in addition to colouring matters. The feedstock is heated up in the Crude/Neutral Oil Economiser or Crude/Neutral Oil Heater to a degumming or bleaching temperature. When there is a need for acid pre-treatment, phosphoric acid is mixed vigorously with the oil in an Acid Mixer to ensure efficient mixing. The resultant mixture is then held in a Retention Tank to allow for the precipitation of gums before going to the Bleacher through the cascade vacuum dryer.

When acid pre-treatment is not required, the feedstock is fed directly to the Bleacher after heating through the cascade vacuum dryer. Bleaching Earth and Activated carbon is added to the oil through a dosing unit which is controlled by PLC. The Bleacher is proprietary and designed with internal partitions and a set of high-efficiency turbine agitators to avoid short cycling and provide the necessary retention time before filtration. The conjunction of a vacuum dryer with a Bleacher is what is unique about “SOFTBLEACH” whereby oil going to the Bleacher is thoroughly dried and deaerated in the cascade vacuum dryer beside the fugitive particles from the Bleacher are counter currently scrubbed by the downcoming oil and hence bleaching earth going to the hot well is avoided. The bleached oil from the Pressure Leaf Filters is transferred to the Bleached oil tank for intermediate storage.