What does falling film evaporation mean?
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What does falling film evaporation mean? Dear sea friends, please help answer this question. Thank you!
Film evaporation is a type of surface evaporation in which the feed liquid flows over a heated surface in the form of a liquid film. Unlike normal evaporation, during falling film evaporation, there is no intense boiling of the liquid feed. During falling film evaporation heat transfer, the heat flux density remains constant along the thickness of the liquid film; heat moves from the heating surface through the liquid film until it is released in the form of latent heat at the free surface. Evaporation generally occurs only on the surface of the liquid film, and it is a type of forced convection heat transfer between the gas and liquid phases inside the tube.
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The liquid is distributed by the fabricing device across the inner wall of the heating tube, forming a liquid film that flows from top to bottom.
Film evaporation is a type of surface evaporation in which the feed liquid flows over a heated surface in the form of a liquid film.
We call this thin-film evaporation: a flowing film of liquid is formed on the heat exchange surface, and heat exchange takes place during this flow, allowing the volatile components in the liquid to be separated.
The material is evenly distributed throughout the heating tubes of the evaporator by a distribution device. Under the influence of gravity, vacuum, and air currents, it flows in a film-like manner from top to bottom; during this movement, it undergoes heat exchange with the steam heated on the outer walls of the heating tubes, resulting in evaporation.
The material flows from top to bottom through the distributor into the tube bundles, where it forms a thin layer along the tube walls and evaporates/boils. The falling film method is suitable for heat-sensitive materials, as the material stays in the heater for a short period of time.
Film evaporation: A type of surface evaporation in which the material flows over a heated surface in the form of a liquid film; therefore, it is suitable for the evaporation of heat-sensitive materials.
The material is evenly distributed across the various heating tubes of the evaporator by a distribution device. Under the influence of gravity, vacuum, and air currents, it flows in a film-like manner from top to bottom; during this movement, it exchanges heat with the steam heated on the outer walls of the heating tubes, thereby evaporating. The main body of the equipment consists of heaters of stages I, II, and III, a separator, a heat pump, a condenser, a sterilizer, insulation pipes, a material pump, a water pump, and an instrument panel. All parts of this device that come into contact with materials are made of high-quality stainless steel. Structure: http://china-heatpipe.net/heatpipe04/05/2006-10-2/061025387828_0_233.htm References: http://china-heatpipe.net/