Multi-stage fractionation

Sulzer-MWB [Metalwerk A. G. Buchs] An obsolete process for recovering naphthalene from a coal tar fraction by multi-stage fractional crystallization from the melt. Formerly operated by Rutgerswerke at Castrop-Rauxel, Germany. 

Reid, A. F. Multi-stage Ion Exchange System for the Fractionation of... 

The extraction, in combination with fractional separation of extracts in a multi-stage separation system, results in high-quality volatile oils [42,44]. Recently, this fractional separation technique has been refined by Reverchon and co-workers for selective precipitation of cuticular waxes and volatile oils [43,56],... 

The hydrocracker simulator was also converted to subroutine form for inclusion in the nonlinear programming model of the Toledo process complex. The subroutine was considerably simplified, however, to save computer time and memory. The major differences are (1) the fractionation section is represented by correlations instead of by a multi-stage separation model, (2) high pressure flash calculations use fixed equilibrium K-values instead of re-evaluating them as a function of composition, and (3) the beds in each reactor are treated as one isothermal bed, eliminating the need for heat balance equations. 

Blood fractionation has been commercially practiced using microfillralion ceramic membranes. A multi-stage system is used where alumina membranes with varying pore... 

Because isotopic fractionation effects are in the magnitude of some few per thousands, they can only be analyzed very inaccurately (see Chap. 3) in one equilibrium stage. Therefore, in many experiments a higher total separation effect is established by multiplication processes. From these results the elementary fractionation effect e can be calculated under certain presuppositions. In principle, a multiplication of the elementary fractionation effect is possible with multi-stage batch experiments (cascade) or with chromatographic systems. 

To demonstrate the capability of this system for an enrichment of heavy calcium isotopes on a scale which is of technical interest, a column (diameter = 1.5 cm) filled up to a height of 195 cm with the resin Kryptofix 222B polymer (189 g resin) was used for an additional multi-stage experiment (eluant = HjO, elution speed = 1 ml/min, 7 °C). One elution cycle with this column has shown that the total isotopic separation is higher compared with the smaller column (Fig. 20). The increase of the total isotopic fractionation is directly proportional to the percentage increase of the resin amount. Furthermore, it was found that the isotopic separation under these conditions is independent of the calcium amount up to 450 mg CaCb... 

Subsurface fluid phases with high noble gas concentrations as well as noble gas fractionation in excess of single step phase fractionation limits may provide field evidence for multi-stage processes of re-solution and effervescence. 

In this method, inert gas (nitrogen with less than 7% oxygen) is circulated between the evaporation zone and multi-stage condensation unit. Because the gas is inert, the restriction which calls for solvent concentration never to exceed a fraction of the... 

Boonyasuwat et al. (2003) suggested a multi-stage foam separation process based on surfactant waste streams to not only concentrate surfactants but also use foam fractionation to remove non-surfactant components from the effluent. With the developed process, anionic and cationic surfactant foam can be concentrated, liquefied and recycled. 

This UK resident filed a patent, published in 1986 in the US, on a rotating still (Moss, 1986 Figure 1.9a and b). Although specified as a separator for light and heavy fractions - multi-stage counter-current distillation - the so-called lamellar bodies normal to the radial flow path are perforated and are shown in the detail in Figure 9b. 

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