Abstract: Liquid material is heated within a first predetermined portion of a confined passageway under pressure and temperature conditions whereby the volatile components of the liquid material are maintained below the boiling point for said volatile components. The heated liquid material is continuously passed from said first predetermined portion into and through a second predetermined portion of the confined passageway which is arranged to form a partial restriction to fluid flow. The liquid material is immediately passed from the partial restriction into a third predetermined portion of the confined passageway which is arranged and configured to provide a relatively elongated, narrow passage having a high ratio of surface area to volume of fluid flow and a predetermined configuration to impart a turbulent flow to the liquid material.