Flow and mass-transfer of two fluids in fiber film extractor-effects of feeding sequence

The fiber film extractor is a novel high-efficiency equipment for liquid-liquid contacting and mass-transfer. In this paper, the effects of the feeding sequences of two liquids added into the fiber film extractor were investigated. Kerosene (O) and aqueous benzoic acid solution (W) were used as the two contacting liquids. Varying the packing density of the fibers in the extractor from 1.89% to 5.08% and the flowrate ratios of the two liquids W/O from 3 to 6, the hydrodynamics and the mass-transfer of the fiber film extractor were studied by using a plexiglass pipe extractor model with 70 mm ID and 2630 mm height. The results show that, if feeding aqueous benzoic acid solution firstly, the mass-transfer coefficient decreases with increasing the flowrate ratio W/O. However, if feeding kerosene firstly, the mass-transfer coefficient increases at first and then decreases with a peak appearing at W/O=5 approximately. For both feeding sequences, the mass-transfer coefficient increases firstly and then decreases with the increase of the fiber packing density, and both the optimal fiber packing densities for these two feeding sequences are in the range of 3.0%~3.5%.