LUWA evaporator

Distillation/Clay Treatment Thin-film distillation under high vacuum, such as Luwa evaporators, separates gas oil, lubricant oils and an asphaltic residue containing most of the additives and contaminants from the used lubricant feedstock. The lubricant base oil stream is finished by clay frealmenl. Overall base oil yields are again 70-80% and significant amounts of spent clay must be disposed of. 

Figure 13.30. Molecular distillation and related kinds of equipment, (a) Principle of the operation of the falling film still (Chemical Engineers Handbook, McGraw-Hill, New York, 1973). (b) Thin-layer evaporator with rigid wiper blades (Luwa Co., Switzerland), (c) The Liprotherm rotating thin film evaporator, for performance intermediate to those of film evaporators and molecular stills (Sibtec Co., Stockholm), (d) Centrifugal molecular still [Hickman, Ind. Eng. Chem. 39, 686 (1947)].

Figure 1. Thin-film evaporator equipped with a fixed blade rotor (Luwa)...

Distillation equipment for soap-lye and esterification cmde requires salt-resistant metallurgy. The solid salt that results when glycerol is vaporized is removed by filtration or as bottoms from a wiped film evaporator. The Luwa scraped wall... 

Thin-film Conduction Evaporator-dryer, wiped-tilm, LUWA... 

Figure 1. Model and material balance for evaporators. (Luwa Corporation)...

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