Papers by Keyword: Process Intensification

Abstract: The object of this study is to intensify the liquid-liquid extraction. Experiments were carried out inside a Rotating Packed Bed (RPB) operating at centrifugal force varying between 100g and 1000g. The system chosen for experimentation was removal of hexavalent chromium from aqueous solution using aliquat-336 as an extractant. The effect of centrifugal force on overall volumetric mass transfer coefficient () was investigated. Mass transfer characteristics of RPB were observed with the variation in rotational speed (300-1100rpm), aqueous phase (0.4-1.2 L/min) and organic phase (0.05-0.15 L/min) flow rate, feed (25-200 mg/L) and extractant (0.5-1.25 vol%) concentration. Significantly higher value of (~20-25 times) was achieved in RPB than that achieved in comparison with conventional packed bed extractor wherein flow is dictated by terrestrial gravity. In other words, same separation efficiency can be obtained within a much smaller rotating extractor.

Abstract: This paper examines the economic costs and benefits of the use of an ultrasonic wire or tape cleaning system. In the last years, major technology improvements made the use of power ultrasound more reasonable for the cleaning of wires. The cavitation of modern high-power ultrasonic processors serves to remove grease, oil, and other contaminations from the surface of the wire. Reduced investment costs and high performance of these ultrasonic wire cleaning systems made them not only competitive but superior to conventional cleaning methods as for example acid baths.

Abstract: An intensified continuous mini-reactor is introduced, to replace traditional discontinuous reactor, using in three-phase catalytic slurry hydrogenation. Under high pressure intensification, continuous mini-reactor behaves excellent performances of mass transfer and heat transfer, and presents the advantages of smaller volume, faster reaction rates, higher conversion and no solvent addition. The steady-state mathematic model is established, and the characteristic times of mass transfer and heat transfer are analyzed based on mass balance and energy balance Eq.s, the results can efficiently help the reactor design and optimization.

Abstract: The recent interest in boiling heat transfer in small diameter tubes has led to the study of boiling heat transfer outside a compact tube bundle of diameter 3mm. The bank comprised 3 columns each of 10 stainless steel electrically heated tubes of 3mm outside diameter, with pitch to diameter ratio of 1.5 in an in-line arrangement. These tests were carried out using distilled water and R113 at nominal atmospheric pressure over a range of heat fluxes between 4-21 kW/m2 for mass fluxes from G=5.6 - 32.8 kg/m2s. The recent three-zone evaporation model developed by Thome, Dupont and Jacobi for boiling inside micro channels was used to compare with experimental results as photographic study showed that bubbles confined within the bundle were responsible for the heat transfer enhancement observed. It was observed that the three state model was promising in its application to the bundle arrangement as the confinement number Co for bundle has been shown to be in the order of 0.63

Abstract: An experimental study has been carried out using a tube bank representing a section of a tube bundle. The bank comprised 3 columns each of 10 stainless steel electrically heated tubes of 3mm outside diameter with pitch to diameter ratio of 1.5 in an in-line arrangement. Flow rate through the test section was controlled. Each tube in the central column was instrumented to permit determination of the tube temperature and heat flux, hence permitting calculation of the heat transfer coefficient. These tests were carried out using distilled water at nominal atmospheric pressure over a range of heat fluxes between 6 - 21 kW/m2. Results of the heat transfer tests are presented and compared with correlations used for conventionally sized bundles. Correlations developed for large tube bundle overestimate the experimental results.

Abstract: The objective of this paper is to present the solution developed to model the chem- ical and thermal coupling occurring in an intensied heat exchanger reactor. The results of this modeling are all the properties of the chemical uid along the conduit, and the temperature distribution in the structure. This will be used to manage a thermal and mechanical reliability study of the heat exchanger reactor.