화학공학소재연구정보센터
Chemical Engineering & Technology, Vol.31, No.7, 1039-1045, 2008
A study on modern high-effective random packings for ethanol-water rectification
Raschig Super-Ring is a modern and high-efficient packing used for intensification of absorption and distillation processes. The aim of this work is to characterize the efficiency of this packing applied to rectification of an important industrial system, ethanol-water, and to compare its efficiency to that of some random packings of the third generation as well as to the structured packing, HOLPACK, which is used in the ethanol production industry. The experiments were carried out in a column installation, 0.213 m in diameter with a packing height of 2.8 m. The column is heated by a number of electrical heaters (total power 45 kW), which can be switched gradually. Operation at total and partial reflux is possible. Eight types of random packings were studied: five types of Raschig Super-Ring, four metallic (with characteristic dimensions 0.5, 0.6, 0.7, and 1") and one of plastic material 0.6"; two types of packing IMTP and one plastic Ralu Flow. Some experiments were conducted at total reflux operation at vapor velocity, 0.253-0.936 m/s, and liquid superficial velocity, 4.44 . 10(-4)-1.63 . 10(-3) m(3)/(m(2)s). Experiments at partial reflux were carried out at constant liquid superficial velocity and changeable vapor velocity as well as at constant vapor velocity and changeable liquid velocity. The results are presented as height of transfer unit, HTU, and height equivalent to a theoretical plate, HETP, as a function of the velocity of phases.