Abstract: A vertical tube evaporator is disclosed comprised of two sets of tubes, one set forming an upflow zone and the other set forming a downflow zone. The liquid to be treated comprised of fresh feed and a recirculating liquid stream is introduced into the upflow zone at an initial velocity of about 0.5 feet per second based on the cross-section area of the tubes. The vapor-liquid stream withdrawn from the first set is then passed through a distribution plate having orifices aligned with the tubes in the second set and of smaller diameter prior to passage thereof through the second set of tubes. The condition of the vapor-liquid stream between the sets of tubes is visually observed to permit adjustment of initial flow rate to the first set of tubes of the evaporator for optimization of heat transfer coefficients.

Abstract: A new process for the continuous deep-fat cooking of a food to produce a processed comestible wherein the food is passed through an elongated cooking zone. Hot cooking oil is introduced and withdrawn from the cooking zone at a plurality of points to produce hydraulic effects which insure proper contact of the food with the cooking oil.Said cooking oil is continuously flowed upwardly through a plurality of spaced points dispersed over the entire bottom surface of the entrance end of the cooking zone and continuously withdrawn downwardly downstream therefrom. Withdrawn oil may be reintroduced directly without being reheated at a point downstream of the point of withdrawal in addition to being recycled to the source of heated cooking oil.