Abstract: A continuous process of contacting crude oils, particularly triglyceride oils, with an acid for the purpose of removing phosphatides and trace metals is disclosed. The acid is introduced into a stream of heated oil immediately ahead of mixing means, such as a static-mixer, capable of achieving an acid droplet size smaller than 10 microns in diameter. The interfacial surface provided by these microscopic droplets allows the acid-oil contacting process to occur essentially instantaneously, requiring less acid and less acid-oil residence-time. The process is useful in treating crude oils prior to alkali-refining or prior to a bleaching treatment in preparation for steam-refining.

Abstract: Triglyceride oils are bleached rapidly and efficiently in a continuous system wherein a stream of the oil is preheated to bleaching temperature and is introduced into a mixing zone in such manner as to provide a swirling motion, bleaching adsorbent containing moisture is added to the surface of the swirling hot oil and water vapor or steam derived from the moisture in the adsorbent forms a protective atmosphere above the surface of the oil to protect it from oxidation. The oil-adsorbent mixture is pumped continuously from the mixer to a bleaching zone consisting of one or more static mixers, which may be unobstructed pipe sections, under flow conditions providing an average residence time of approximately one minute. The flow regime in the bleaching zone may be laminar or turbulent. Optionally, the oil-adsorbent mixture may flow continuously from the mixing zone to a vacuum dryer where it is deaerated and dried to optimum moisture content for bleaching prior to being pumped to the bleaching zone.