Prediction Of Separation Performance Research Articles

Design of partial cross-sectional geometry and prediction of separation performance in the spiral separator

ABSTRACT Understanding the influence mechanism of the partial cross-sectional geometry of a spiral separator on the flow field characteristics and particle separation performance is conducive to the design of a combined cross-section profile. The impact of the trough slope in the inner and middle troughs on the flow field characteristics and particle separation performance was investigated by CFD methods. The results show that the average depth of the flow film, the average tangential velocity, and the average radial velocity in the partial radial region are linearly related to the trough slope. With the increase in the trough slope in the inner and middle troughs (r = 30–110 mm), the radial velocity reversal position will decline, resulting in an enlarged proportion of the outward flow. Adjusting the trough slopes of the two straight segments in the inner and middle troughs will have a positive effect on the precise segregation of particles. In comparison, changing the trough slope in the middle trough containing the miscible band had a more significant effect on particle separation. A maximum separation efficiency of 80.80% was obtained with a trough slope in the middle trough of 5°and a splitter position of 95 mm.

CO2 separation by supported ionic liquid membranes and prediction of separation performance

Four supported ionic liquid membranes (SILMs) were prepared by fixing ionic liquids (ILs) 1-butyl-3-methylimidazolium dicyanamide ([BMIM][DCA]), acetate ([BMIM][AC]), trifluoromethanesulfonate ([BMIM][TfO]) and bis ((trifluoromethyl)sulfonyl)imide ([BMIM][NTf2]), respectively, in Polyvinylidene Fluoride (PVDF) membranes and used for the separation of CO2/H2 and CO2/N2 gas mixtures. Density function theory (DFT) calculations were performed to predict the complexation energy (EC) between the ILs and CO2, H2 and N2 molecules as well as the gas separation performance of their SILMs. Experimental results indicate that the gas permeation rate of the SILMs increases with increasing temperature. [BMIM][TfO] SILM showed the best separation performance for CO2/H2 with permselectivity of 16.2 and CO2 permeability of 1966 Barrer at 40°C. [BMIM][AC] SILM showed the best separation efficiency for CO2/N2 with permselectivity of 21.8 and CO2 permeability of 520 Barrer at 30°C. The separation capacity of SILMs for the CO2/H2 and CO2/N2 follows the increasing order of the Ec differences.

Prediction of Separation Performance of Dry High Intensity Magnetic Separator for Processing of Para-Magnetic Minerals

High intensity dry magnetic separators are gaining popularity for the separation of para-magnetic minerals due to the cost economic factor. Induced roll magnetic separator is found to be an effective dry separator for the separation of fine particles. Separation efficiency of this separator depends on mineral characteristics and the design features of equipment along with the optimization of process variables. Present investigation focuses on the prediction and validation of separation performance of minerals while treating in induced roll magnetic separator. Prediction of the separation is expressed in terms of separation angle at which a particle leaves the rotor surface by using a modified particle flow model derived by Cakir. The validation of the model is carried by capturing the particle trajectory using an image analyzer. It is found that Cakir’s mathematical model produces reliable results and a new model is proposed to increase the reliability of separation angle prediction by including the particle shape factor.

Phenomena and Modeling of Hydrophobic Interaction Chromatography

Comprehension of the mechanisms of hydrophobic interaction chromatography is not as deep as for other chromatographic steps. This article shows the combination of modeling and experimental model parameter determination. Original mammalian cell culture is applied for validation instead of often-used test systems with for example, three pure proteins. This approach can have a huge benefit for process development and optimization of production processes under project conditions. To simulate the separation by hydrophobic interaction chromatography, a distributed plug flow model with inner pore diffusion is applied. The needed model parameters are determined by small scale experiments on a 1 ml column to reduce feed amount consumption and experimental procedure. Effects caused by system setup are optimized in relation to the volume. Gradient experiments are performed for the determination of isotherm parameters. The model parameters determined are experimentally validated at different set-ups of operation parameters as well as scaled up to 10 ml columns. The practicability of the proposed stepwise procedure of physico-chemical modeling in combination with laboratory scale experiments for the prediction of separation performance of original mammalian cell culture is proved. A model parameter determination directly with fermentation mixture is as well feasible.

Simulation of ternary distillation in a heat integrated distillation column (HIDiC) with a rate-based model

The proposed of the present work is to develop a method for rigorous prediction of separation performance of the HIDiC. A process simulator (gPROMS) for prediction of performance of the HIDiC with random packing is developed by rate-based model using Maxwell-Stefan equations. The vapor and liquid flow rates of HIDiC increased from the bottom to the top in the stripping section. In the rectifying section, however, the flow rates decreased from the bottom to the top. Evaporation of liquid in the stripping section and the condensation of vapor in the rectifying section take place. Comparison was made observed data from a bench-scale separation (benzene-toluene system) HIDiC plant, about 16 m in height and 254 mm in diameter (concentric R&A sections) and simulation results. The energy-saving ratio shows a good agreement with observed data. The bench HIDiC showed about 40% reduction of energy consumption compared with the conventional distillation column. The effect of nonequilibrium of temperature in the HIDiC is also discussed.

Heat and Mass Transfer Model Approach to Prediction of Separation Performance of Cryogenic Air Separation Plant by Packed Columns with Structured Packing.

A process simulator for prediction of separation performance of a cryogenic air separation plant by packed columns with structured packing is developed by use of our heat and mass transfer model. The basic equations for the simulation are mass transfer correlations which were proposed in our previous work (Egoshi et al., 2000). Comparison of observed data from a pilot-scale cryogenic air separation plant, which consisted of a 710 mm-diameter high pressure sieve plate column for feed to low pressure column, a 500 mm-diameter low pressure packed column with structured packing for production of pure grade nitrogen and oxygen, and a 380 mm-diameter argon column with structured packing for production of crude argon is made. Predicted concentration profiles in the low pressure column and the ones in the argon column show good agreement with observed data. The effect of liquid feed location, side-cut location, vapor-liquid ratio of the feeds to the low pressure column on purity of the product nitrogen, oxygen and crude argon are also discussed.